Virtual Library

Start Your Search

S.P. Finn



Author of

  • +

    MINI 08 - Prognostic/Predictive Biomarkers (ID 106)

    • Event: WCLC 2015
    • Type: Mini Oral
    • Track: Biology, Pathology, and Molecular Testing
    • Presentations: 1
    • +

      MINI08.10 - Co-Occurrence of Driver Mutations of MAPK and PI3K Pathways in Non Small Cell Lung Cancer: A Report from Lung Cancer Genomics Ireland (LCGI) Study (ID 2627)

      16:45 - 18:15  |  Author(s): S.P. Finn

      • Abstract
      • Presentation
      • Slides

      Background:
      The mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) pathways are frequently altered in human cancers. Targeting these pathways is an attractive therapeutic strategy in malignant disease. The frequency of single and dual pathway alterations varies substantially across various cancers. Co-occurrence of the MAPK and PI3K pathway aberrations is reported in 5-7% of melanomas, gastric and colorectal cancers, and is associated with a worse clinical outcome. In this report we aim to determine the co-occurrence of the MAPK and PI3K pathway mutations in a large cohort of surgically resected NSCLC tumors.

      Methods:
      We used the platform of Sequenom’s MassArray to perform genotyping for 548 somatic hotspot mutations in 49 genes including genes in the MAPK and PI3K pathways in surgically resected NSCLC tumors. MAPK pathway genes that were screened include: KRAS, HRAS, BRAF, RAF1, MAP3K1, MAP3K2, MAP3K3, MAP3K4, MAP3K5, MAP2K1, MAP2K2, MAP2K3, and PTPN11. PI3K pathway genes that were screened include: PIK3CA, PIK3R1, PIK3R2, PTEN, PDPK1, AKT1, AKT2, and MTOR. Fisher’s exact test was used to determine the statistical significance of association between the MAPK and PI3K pathway mutations. The strength of association was determined in the form of odds ratio.

      Results:
      NSCLC tumors from 356 patients (258 squamous cell, 98 adenocarcinomas) were tested using Sequenom’s MassArray. The frequency of mutations in the MAPK and PI3K pathways was 22.5% (n=80) and 22.8% (n=81) respectively. Among these patients, 38 patients had mutations in both pathways (i.e: 47.5% of patients with a MAPK pathway mutation also had a mutation in the PI3K pathway, and 46.9% of patients with a PI3K pathway mutation also had a mutation in the MAPK pathway, see table 1). Fisher’s exact test revealed that mutations in the MAPK and the PI3K pathways are mutually inclusive (p<0.0001, odds ratio=4.95, 95% CI 2.9-8.5) Table 1: The co-occurrence of MAPK and PI3K pathway mutations in NSCLC

      Pathway/no of patients PI3K WT PI3K MT
      MAPK WT 235 43
      MAPK MT 42 38


      Conclusion:
      38 (10.7%) of 356 NSCLC patients included in the LCGI study had hotspot somatic mutations in both the MAPK and PI3K pathways. Contrary to previous reports, we observed that activating mutations of the MAPK and PI3K pathways are mutually inclusive in NSCLC. These findings may have implications in designing clinical trials of targeted therapies in lung cancer.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    MINI 34 - RNA and miRNA (ID 162)

    • Event: WCLC 2015
    • Type: Mini Oral
    • Track: Biology, Pathology, and Molecular Testing
    • Presentations: 1
    • +

      MINI34.07 - A Novel microRNA Signature Associated with Cisplatin Resistance in NSCLC (ID 2709)

      18:30 - 20:00  |  Author(s): S.P. Finn

      • Abstract
      • Presentation
      • Slides

      Background:
      MicroRNAs (miRNAs) are an abundant class of small non-coding RNAs that range in size from 19 to 25 nucleotides. Alteration in miRNA expression can cause them to act as either tumour suppressor or oncogenes. They have also been shown to regulate a number of processes involved in tumour biology such as metastasis, invasion and angiogenesis. More recently, miRNAs have been linked to chemo- and radio-resistance in many solid tumours, including lung cancer.

      Methods:
      An isogenic model of cisplatin resistance was established by chronically exposing a panel of NSCLC cell lines (MOR, H460, A549, SKMES-1, H1299) to cisplatin for 12 months, generating cisplatin resistant (CisR) sublines from their corresponding age-matched parental (PT) cells. MicroRNA expression profiling was carried out using 7th generation miRCURY LNA™ microRNA arrays consisting of 1,919 miRNAs (Exiqon). MicroRNAs that were significantly increased in CisR sublines were inhibited using antagomirs (Exiqon), while those that were significantly decreased were over-expressed using pre-miRs (Ambion). Functional studies examining clonogenic survival ability, proliferation (BrdU) and apoptosis (Annexin V/PI) were subsequently carried out in the presence or absence of cisplatin. To examine the translational relevance of these microRNAs, their expression was further examined in a cohort of pre-treatment matched normal and tumour lung tissues from NSCLC patients of different histological subtypes. Validation of this miRNA signature is currently being investigated in serum samples from this same cohort of patients and normal controls.

      Results:
      MicroRNA profiling analysis identified ten miRNAs which were significantly altered between parental and corresponding cisplatin resistant lung cancer cell lines. Validation of these miRNAs by real-time PCR (qPCR) identified a specific 5-miR signature that was significantly altered in CisR cells relative to their parental counterparts. Modification of these microRNAs altered the response of resistant cells to the cytotoxic effects of cisplatin and decreased the clonogenic survival of CisR cells when treated with increasing doses of cisplatin (0.1µM-10μM). Significant differential expression was found between normal and tumour tissues across each histological subtype, highlighting the potential use of these microRNAs as markers of response to cisplatin therapy in NSCLC patients. Three miRNAs (miR-A, B, C) belonging to the same family were significantly altered in tumour lung tissue of adenocarcinoma and squamous cell histology compared to matched normal lung tissue. MicroRNA-D expression was significantly altered in squamous cell carcinomas while miR-E was differentially expressed in adenocarcinomas only. Data relating to the expression of this novel signature in the circulation of our NSCLC patient cohort and normal controls will be presented at WCLC 2015.

      Conclusion:
      We have identified and validated a novel miRNA signature associated with cisplatin resistance in a panel of cisplatin resistant cell lines and in patient lung tumours. Genetic manipulation of these specific miRNAs in vitro altered the cisplatin resistant cell response to the cytotoxic effects of cisplatin chemotherapy. The data obtained from this study may provide a basis for the potential development of a companion diagnostic for lung cancer patients who are most likely to benefit, or not, from cisplatin chemotherapy.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    ORAL 37 - Novel Targets (ID 146)

    • Event: WCLC 2015
    • Type: Oral Session
    • Track: Biology, Pathology, and Molecular Testing
    • Presentations: 1
    • +

      ORAL37.05 - Prevalence and Clinical Association of MET Gene Amplification in Patients with NSCLC: Results from the ETOP Lungscape Project (ID 444)

      16:45 - 18:15  |  Author(s): S.P. Finn

      • Abstract
      • Slides

      Background:
      The reported prevalence of MET gene amplification in non-small cell lung cancer (NSCLC) varies from 0-21% and clinical correlations are emerging slowly. In a well-defined NSCLC cohort of the ETOP Lungscape program, we explore the epidemiology, the natural history of MET amplification and its association with MET overexpression, overall survival (OS), relapse-free survival (RFS) and time to relapse (TTR).

      Methods:
      Resected stage I-III NSCLC, identified based on the quality of clinical data and FFPE tissue availability, were assessed for MET gene copy number (GCN) and expression analysis using silver in-situ hybridization (SISH) and immunohistochemistry (IHC), respectively, on TMAs (MET and centromere-specific probes; anti total c-MET antibody, clone SP44; Ventana immunostainer). MET amplification was defined as MET/centromere ratio ≥2 with average MET GCN ≥4, high MET GCN at two levels as ≥median CGN and ≥5 (irrespective of amplification) and MET IHC+ as 2+ or 3+ intensity in ≥50% of tumor cells. Sensitivity analysis to define the amplification’s thresholds was also performed. All cases were analysed at participating pathology laboratories using the same protocol, after successful completion of an external quality assurance (EQA) program.

      Results:
      Currently 2709 patients are included in the Lungscape iBiobank (median follow-up 4.8 years, 53.3% still alive). So far, 1547 (57%) have available results for MET GCN with amplification detected in 72 (4.7%; 95%CI: 3.6%, 5.7%) and high MET GCN (≥5) in 65 (4.2%; 95%CI: 3.2%, 5.2%). The median value of average MET GCN per cell is 2.3. IHC MET expression is available for 1515 (98%) of these cases, 350 (23%) of which are MET IHC positive [170 cases (49%) 3+, 180 (51%) 2+]. The median age, for the cohort of 1547 patients, is 66.2 years, with 32.8% women, and 13.5%, 29.7%, 54% never, current, former smokers, respectively. Stage distribution is: IA 23.6%, IB 24.6%, IIA 17%, IIB 12.1%, IIIA 20.9%, IIIB 1.8%, while 52.7%, are of adenocarcinoma and 40.0% of squamous histology. MET amplification and high MET GCN (≥5) are not significantly associated with any histological tumor characteristics or stage (multiplicity adjusted alpha: 0.005). High MET GCN (≥2.3) is less frequent in current smokers (38.3% vs. 55.6% for former or non-smokers, p<0.001). MET amplification and high MET GCN are significantly associated with IHC MET positivity (p<0.001 in all cases). MET amplification is present in 9.7% of IHC MET+ vs 3.1% of IHC MET- patients and high MET GCN (≥5) in 8.6% of IHC MET+ vs 2.8% of IHC MET- patients. MET amplification ranges from 0 to 16% between centers, while high MET GCN (≥5) and (≥2.3) from 0% to 12%, and 11.8% to 98.9%, respectively. MET amplification and both levels of high MET GCN are not associated with OS, RFS or TTR.

      Conclusion:
      The preliminary results for this large, predominantly European, multicenter cohort demonstrate that MET amplification assessed by SISH prevails in 4.7% of NSCLC, is associated with strong MET expression, and has no influence on prognosis. The large inter-laboratory variability in GCN despite EQA efforts may highlight a critical challenge of MET SISH analysis in routine practice.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    ORAL 42 - Drug Resistance (ID 160)

    • Event: WCLC 2015
    • Type: Oral Session
    • Track: Biology, Pathology, and Molecular Testing
    • Presentations: 1
    • +

      ORAL42.06 - Cancer Stem Cells: Targeting Aldehyde Dehydrogenase 1 (ALDH1) as a Novel Strategy in Cisplatin Resistant Non-Small Cell Lung Cancer? (ID 2724)

      18:30 - 20:00  |  Author(s): S.P. Finn

      • Abstract
      • Presentation
      • Slides

      Background:
      Cisplatin is the backbone of chemotherapeutic treatment of lung cancer. Unfortunately the development of resistance has become a major challenge in the use of this cytotoxic drug. Understanding the mechanisms underlying this resistance phenotype may potentially result in the development of novel agents that may enhance the sensitivity of cisplatin chemotherapy in the clinical setting. The root of this resistance is hypothesized to be due to the presence of a rare cancer stem cell (CSC) population within the tumour that can reform a heterogenic tumour, resulting in recurrence and resistance following cisplatin chemotherapy.

      Methods:
      An isogenic model of cisplatin resistance was established by chronically exposing a panel of NSCLC cell lines (H460, SKMES, H1299) to cisplatin for 12months, thereby creating cisplatin resistant (CisR) sublines and their corresponding age-matched parental (PT) cells. To identify a CSC population within the resistant sublines, PT and CisR cell lines representing the three classifications of NSCLC were stained for ALDH1 using the Aldefluor kit (Stemcell Technologies). ALDH1 positive (+ve) and negative (-ve) subpopulations were isolated and their functional characteristics assessed. Proliferation and survival of ALDH1+ve fractions in response to cisplatin was assessed using BrdU and clonogenic survival assays relative to ALDH1-ve cells. ALDH1 subpopulations were examined for asymmetric division and expression of the human embryonic stem cell markers Nanog, Oct-4, Sox-2, Klf-4 and c-Myc and CD133. To confirm that this ALDH1+ve population is associated with cisplatin treatment, PT and CisR cells were chronically exposed to high dose cisplatin for 2 weeks and stained for ALDH1 and re-assessed for stemness qualities. Apoptosis and clonogenic survival of PT and CisR cells was assessed in response to selective inhibition of ALDH1 using diethylaminobenzaldehyde (DEAB) in combination with cisplatin. Xenograft studies in NOD/SCID mice are currently under investigation to examine the tumourigenic potential of isolated subpopulations of ALDH1.

      Results:
      A significant ALDH1+ve population was detected in CisR sublines, but not in their PT counterparts. Characterisation of the ALDH1+ve subpopulation confirmed enhanced expression of stemness markers, increased resistance and clonogenic survival in response to cisplatin compared to their ALDH1-ve counterparts, and the ability to asymmetrically divide. Chronic cisplatin treatment of the PT cell lines for 2 weeks increased resistance to cisplatin, increased stemness marker expression and induced the emergence of an ALDH1+ve population. Chronic high dose cisplatin treatment significantly expanded the ALDH1+ve population in the CisR cell lines. Importantly, inhibition of ALDH1 activity, with DEAB, decreased the mean cell viability, clonogenic survival capacity and increased cisplatin-induced apoptosis of the CisR cells when used in combination with cisplatin, an effect not seen in the PT cells.

      Conclusion:
      In this study, we have demonstrated the existence of a putative CSC population within our model of isogenic cisplatin resistant cell lines and suggest a role for ALDH1 inhibition as a potential therapeutic strategy in re-sensitizing chemoresistant lung cancer cells to the cytotoxic effects of cisplatin. Further studies will focus on re-purposing of FDA-approved ALDH1 inhibitor, Disulfiram (Antabuse), used in the treatment of chronic alcoholism as a potential combination therapy to prime chemoresistant cells to cisplatin.

      Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    P1.08 - Poster Session/ Thymoma, Mesothelioma and Other Thoracic Malignancies (ID 224)

    • Event: WCLC 2015
    • Type: Poster
    • Track: Thymoma, Mesothelioma and Other Thoracic Malignancies
    • Presentations: 1
    • +

      P1.08-013 - Long Non-Coding RNAs Associated with Lysine Demethylases Are Overexpressed and Epigenetically Regulated in Malignant Pleural Mesothelioma (ID 1757)

      09:30 - 17:00  |  Author(s): S.P. Finn

      • Abstract
      • Slides

      Background:
      Malignant pleural mesothelioma (MPM) is an aggressive rare cancer affecting the pleura and is predominatly associated with prior exposure to asbestos. Treatment options are limited, and most patients die within 24 months of diagnosis. The current standard of care for MPM patients is a combination of cisplatin and pemetrexed (or alternatively cisplatin and raltitrexed), yet most patients die within 24 months of diagnosis. Lysine Demethylases (KDMs) containing a JmjC domain regulate gene expression by “erasing or removing” methylation on histones in chromatin. Members of this family are frequently found to have aberrant expression in cancer and currently are actively pursued as candidate pharmaceutical therapeutic targets. We have shown that various members of the JmjC family of KDMs have significantly altered expression in MPM. Long non-coding RNAs (lncRNAs) belong to a group of RNAs that are usually more than 200 nucleotides long and play important roles in different regulatory processes, including regulation of gene expression. Several lncRNAs have also been shown to play a role as oncogenic molecules in different cancer cells (one example being HOTAIR). Altered expression of lncRNAS therefore make them candidate biomarkers with diagnostic and therapeutic potential in cancer. Several such lncRNAs have now been shown to locate to the same chromosomal region as various KDMs. These are KDM4A/KDM4A-AS1, KDM5B/KDM5B-AS1 (also known as PCAT6), KDM5C/ AY927613.1 and JARID2/JARID2-AS1. We therefore examined the expression of these lncRNAs in MPM.

      Methods:
      A panel of MPM cell lines were screened for expression of KDM4A-AS1, KDM5B-AS1, AY927613.1 and JARID2-AS1 by RT-PCR. lncRNA transcript levels were subsequently examined by RT-PCR in a cohort of snap-frozen patient samples isolated at surgery comprising benign, epithelial, biphasic, and sarcomatoid histologies. The effects of KDM and HDAC inhibitors on their expression was also examined.

      Results:
      The expression of the various lncRNAs was detectable across our panel of cell lines. In primary tumours the expression of these lncRNAs were significantly elevated in malignant MPM compared to benign pleura (p<0.05), and significant differences were also observed when samples were analysed across different histological subtypes.

      Conclusion:
      The expression of these lncRNAs are significantly altered in MPM. We have cloned KDM4A-AS1 and PCAT6 into overexpression constructs and future studies will assess the effects of these lncRNAs overexpression on mesothelioma proliferation, cellular health and gene expression to determine their potential role in mesothelioma.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    P2.04 - Poster Session/ Biology, Pathology, and Molecular Testing (ID 234)

    • Event: WCLC 2015
    • Type: Poster
    • Track: Biology, Pathology, and Molecular Testing
    • Presentations: 2
    • +

      P2.04-057 - Targeting PIM Kinase in NSCLC (ID 933)

      09:30 - 17:00  |  Author(s): S.P. Finn

      • Abstract
      • Slides

      Background:
      PIM proteins belong to a family of serine/threonine kinases composed of 3 isoforms, PIM1, PIM2 and PIM3, that play a key role in cell cycle regulation, have potent anti-apoptotic activity and play a role in the homing and migration of metastatic cells. Furthermore, PIM kinases have also been shown to be activated in response to Akt pathway inhibition, indicating a role in adaptive responses to inhibition of this pathway potentially leading to treatment resistance. Thus, there is a strong rationale for combining PIM kinase inhibition with inhibition of the Akt pathway (i.e., inhibitors of EGFR, PI3K, Akt and mTOR). PIM kinase has been recognised as a therapeutic target particularly in haematological malignancies however the role of PIM kinases in solid tumours and NSCLC in particular are less well characterised. This study is the first to elucidate the expression of all 3 PIM isoforms in NSCLC cell lines and patient tumours as well as to examine the effect of Inflection Bioscience Ltd novel dual PI3K/PIM kinase (IBL-202) and triple PI3K/mTOR/PIM kinase (IBL-301) targeted therapies in-vitro and in-vivo.

      Methods:
      PIM 1/2/3 protein expression was quantified by western blot analysis in a panel of NSCLC cell lines and 40 matched normal/tumour tissues from NSCLC patients (20 adenocarcinoma and 20 squamous cell carcinoma). PIM kinase expression was correlated to patient clinicopathological characteristics and survival data. The effectiveness of IBL-202 and IBL-301 on proliferation and apoptosis in NSCLC cell lines were examined by BrdU and Annexin V/PI FACS analysis, respectively. A head-to-head in-vivo study of IBL-202 vs. IBL-301 in xenograft nude mice formed using H1975 cells is ongoing.

      Results:
      All 3 isoforms of PIM kinase are highly expressed across a panel of NSCLC cell lines. PIM kinase is expressed in ~ 90% of NSCLC tumour tissues across all stages of the disease. IBL-202 and IBL-301 induced apoptosis and decreased cell proliferation in NSCLC cell lines at micromolar concentrations in-vitro. The in-vivo study is ongoing and results will be presented.

      Conclusion:
      PIM kinase is a promising new therapeutic target for the treatment of NSCLC patients. Dual PI3K/PIM kinase (IBL-202) and triple PI3K/mTOR/PIM kinase (IBL-301) targeted therapies have demonstrated pro-apoptotic and anti-proliferative activity in-vitro and in-vivo and should be considered in the treatment of NSCLC patients.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

    • +

      P2.04-109 - Epithelial-To-Mesenchymal Transition (EMT) and Acquired Resistance to PI3K-mTOR Inhibition in NSCLC (ID 934)

      09:30 - 17:00  |  Author(s): S.P. Finn

      • Abstract
      • Slides

      Background:
      The PI3K-Akt-mTOR pathway regulates cell growth and proliferation and is often dysregulated in NSCLC, making it an attractive therapeutic target in this setting. GDC-0980 is a selective dual inhibitor of PI3K and mTOR, which is currently in Phase II clinical trials for solid tumours. As with all targeted therapies, acquired resistance to GDC-0980 is anticipated to be a major hurdle in the success of this drug. The aims of this project are to (i) elucidate the frequency of PIK3CA mutations in an Irish cohort of NSCLC patients and (ii) develop and characterise three cell line models of resistance to GDC-0980, each representing a different molecular subtype of NSCLC, in order to identify biomarkers of response/resistance to the drug that may dictate beneficial treatment strategies.

      Methods:
      DNA was extracted from 250 NSCLC patient tissue samples, and screened for 547 clinically relevant mutations in 46 genes using the Sequenom platform. H460, A549, and H1975 cells were cultured in GDC-0980 at IC50 concentrations over a period of several months, along with matched ‘parent’ cell lines. Development of resistance was assessed by monthly BrdU proliferation assays. Cell growth patterns were compared across the sensitive and resistant cell lines in real time using the xCELLigence platform. Cell lines were then interrogated for alterations in DNA (Sequenom), mRNA (SABiosciences arrays profiling expression of >150 genes), miRNA (Exiqon expression profiling of 2100 miRNAs) and protein (R&D Phospho Kinase array expression profiling of 43 kinases and 2 associated total proteins, PTMScan[®] Ubiquitin Remnant Motif (K-ε-GG) Kit from CST and Western blot analysis).

      Results:
      PIK3CA mutations occur in ~5% adenocarcinomas & 12% squamous cell carcinomas. H1975 cells (PIK3CA mutant and activated pAkt (Ser473/Thr308), pmTOR, pS6R) were most sensitive to GDC-0980, however they were the first to develop resistance to the drug. Results obtained from xCELLigence studies identified H1975 resistant (H1975R) cells as having the highest cell index out of all parent and resistant cell lines after 100 hours of cell growth, suggesting that these are the most aggressive cells. Initially a 33 miRNA signature was identified contrasting H1975P and H1975R. qPCR validation of miR-205 (a regulator of EMT) identified expression in H1975P cells but miR-205 was undetectable in H1975R cells. mRNA expression of Zeb1 & Zeb2 (direct targets of miR-205) were increased in H1975R cells compared to H1975P cells. 1,200 proteins were found to be differentially expressed between H1975P and H1975R cells. Increased expression of EMT proteins vimentin, desmin and filamin was detected in H1975R cells (p < 0.05, fold change >2). Vimentin overexpression in H1975R cells was confirmed by western blot analyis. Activation of EMT was identified as one potential mechanism of resistance to GDC-0980 in H1975R cells.

      Conclusion:
      The PI3K-mTOR pathway is frequently mutated in NSCLC, in particular squamous cell carcinoma, making it an ideal therapeutic target. Acquired resistance to GDC-0980 developed rapidly in NSCLC cell lines, (4-6 months) and correlates to the induction of EMT. Further elucidation of EMT regulation is under investigation and is crucial to the design of improved treatment protocols.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    P2.08 - Poster Session/ Thymoma, Mesothelioma and Other Thoracic Malignancies (ID 225)

    • Event: WCLC 2015
    • Type: Poster
    • Track: Thymoma, Mesothelioma and Other Thoracic Malignancies
    • Presentations: 1
    • +

      P2.08-006 - The JmjC Family of Lysine Demethylases Are Overexpressed and Potential Therapeutic Targets in Malignant Pleural Mesothelioma (ID 1753)

      09:30 - 17:00  |  Author(s): S.P. Finn

      • Abstract
      • Slides

      Background:
      Malignant pleural mesothelioma (MPM) is an aggressive rare cancer affecting the pleura and is predominatly associated with prior exposure to asbestos. Treatment options are limited, and most patients die within 24 months of diagnosis. The current standard of care for MPM patients is a combination of cisplatin and pemetrexed (or alternatively cisplatin and raltitrexed), yet most patients die within 24 months of diagnosis. There is therefore an urgent unmet need to identify new therapeutic options for the treatment of MPM. Asbestos fibres contain of transition metals and their ability to both adsorb and accumulate these metals was one of the first mechanisms suggested for explaining the toxic and particularly carcinogenic effects of asbestos. One of the transition metals in asbestos fibres is iron, and therefore asbestos fibres may cause an alteration of iron homeostasis in the tissue. In addition, asbestos fibres have also been shown to have high affinity for histones, and therefore may result in high accumulation of iron around chromatin. Lysine Demethylases (KDMs) containing a JmjC domain require both Fe2+ and 2-oxoglutarate as co-factors to regulate gene expression by “erasing or removing” methylation on histones in chromatin. Members of this family are frequently found to have aberrant expression in cancer and currently are actively pursued as candidate pharmaceutical therapeutic targets. Given that asbestos increases iron levels, this may result in aberrant KDM activity, and these KDMs could therefore be novel candidate targets in mesothelioma. We therefore examined the expression of several JmjC containing KDMs in MPM and assessed their potential for therapeutic intervention in mesothelioma using existing small molecule inhibitors.

      Methods:
      A panel of MPM cell lines were screened for expression of KDM4A-D, KDM5A/B and KDM6A/B by RT-PCR. mRNA levels were subsequently examined by RT-PCR in a cohort of snap-frozen patient samples isolated at surgery comprising benign, epithelial, biphasic, and sarcomatoid histologies. IHC was performed for KDM4A on a cohort of FFPE specimens. The effects of treatments with small molecule inhibitors targeting these proteins on both cellular health and gene expression were assessed.

      Results:
      The expression of the various KDMs was detectable across our panel of cell lines. In primary tumours the expression of these KDMs were significantly elevated in malignant MPM compared to benign pleura (p<0.05), and significant differences were also observed when samples were analysed across different histological subtypes. Treatment of mesothelioma cell lines with various small molecule inhibitors caused significant effects on cellular health and on the expression of a panel of genes.

      Conclusion:
      The expression of KDMs are significantly altered in MPM. Small molecule inhibitors directed against these KDMs show potential therapeutic efficacy with significant anti-proliferative effects. We continue to assess the effects of these compounds on gene expression and cellular health to confirm their potential utility as novel therapies for the treatment of MPM.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    P3.01 - Poster Session/ Treatment of Advanced Diseases – NSCLC (ID 208)

    • Event: WCLC 2015
    • Type: Poster
    • Track: Treatment of Advanced Diseases - NSCLC
    • Presentations: 1
    • +

      P3.01-022 - A Prospective Multicenter Study for ALK IHC+ Metastasized NSCLC (ID 2566)

      09:30 - 17:00  |  Author(s): S.P. Finn

      • Abstract
      • Slides

      Background:
      Pulmonary adenocarcinomas may harbor driver mutations, that sensitize tumors to drugs that specifically target the genetic alteration. Metastasized NSCLC with an EML4-ALK translocation are sensitive to a range of tyrosine kinase inhibitors, of which crizotinib is most extensively studied. ALK-positive NSCLC was determined in a phase III trial with fluorescence in situ hybridisation (ALK FISH+). ALK immunohistochemistry (IHC) seems to run parallel with ALK FISH positivity. However discrepant cases occur, which include ALK IHC+ FISH-. The aim of this study is to collect cases with ALK IHC+ and compare within this group response to crizotinib treatment of ALK FISH+ cases with ALK FISH- cases.

      Methods:
      A prospective multicenter investigator initiated research study was started in Europe. This study is supported by Pfizer. Cases diagnosed with ALK IHC+ lung cancer (5A4 or D5F3) treated with crizotinib are collected centrally. Slides are submitted centrally for validation of ALK IHC (with ETOP and Ventana protocol), ALK FISH (with Vysis probes) and DNA analysis.

      Results:
      The study started on April 1 2014 and is still open. Currently 10 centers are actively participating. 1443 cases have been examined with ALK IHC of which 39 (2.7%) recorded positive. 24 cases have been submitted to the database. The validation process is still ongoing. The fraction of ALK IHC+ FISH- cases is low. Two cases with ALK IHC+ FISH- metastastatic NSCLC responded to crizotinib treatment. In two cases ALK positivity could not be confirmed (ALK IHC- and ALK FISH-). These patients had progressive disease following crizotinib treatment.

      Conclusion:
      A clinically relevant question what the effect of ALK inhibitor treatment is on metastatic NSCLC ALK IHC+ FISH- compared to ALK IHC+ FISH+ is examined. Other centers with interested collaborating physicians are invited to participate.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

  • +

    P3.04 - Poster Session/ Biology, Pathology, and Molecular Testing (ID 235)

    • Event: WCLC 2015
    • Type: Poster
    • Track: Biology, Pathology, and Molecular Testing
    • Presentations: 2
    • +

      P3.04-009 - Evaluation of RT-PCR Methodology for ALK Assessment in Patients with NSCLC in Europe: Results from the ETOP Lungscape Project (ID 1506)

      09:30 - 17:00  |  Author(s): S.P. Finn

      • Abstract
      • Slides

      Background:
      ALK rearrangement is documented in 2%-7% of NSCLC, depending on the population studied and detection method used. Although the reverse transcriptase-polymerase chain reaction (RT-PCR) was the first used and published method, fluorescence in situ hybridization (FISH) has become the primary standard diagnostic method. Recently, immunohistochemistry (IHC) has also proven to be a reproducible, faster and sensitive technique. This is one of the first studies concurrently comparing all three techniques in resected lung adenocarcinomas from the large ETOP Lungscape cohort.

      Methods:
      95 cases from the ETOP Lungscape iBiobank, selected based on any degree of IHC staining (clone 5A4 antibody, Novocastra, UK), were examined by ALK FISH (Abbott Molecular, Inc.; Blackhall, JCO 2014) and central RT-PCR. For the latter, formalin-fixed, paraffin-embedded (FFPE) unstained slides were collected from participating centers. Slides were de-paraffinized, Toluidine Blue stained, and tumors macro-dissected. Tissue digestion and RNA extraction were performed (Qiagen RNeasy FFPE Kit). Using primers described in the literature covering most of ALK known translocations, RT-PCR (Superscript One-Step RT-PCR with Platinum Taq – 40 loops) was performed, followed by capillary electrophoresis in two separate mixes. Co-amplification of B-actin was done to validate the procedure and RNA quality. All tests were duplicated.

      Results:
      76 of 95 RT-PCR had adequate RNA quality (B-actin co-amplification present). Among these, 18 were FISH positive, 16 were RT-PCR positive, including EML4-ALK V3a/b in 7, V1 in 5, V2 in one, and undetermined variants in 3 cases. 53 of 54 FISH negative cases were also RT-PCR negative (98%). 15 of 18 FISH positives harbored a translocation by RT-PCR (83%). Among the 4 discrepant cases, 2 FISH+/RT-PCR- cases had IHC H-scores of 180 and 260, and 98.3% and 95% of rearranged cells by FISH, probably corresponding to variants not covered by the RT-PCR. One had an IHC H-score of 5, and 16% cells rearranged on FISH, most probably corresponding to a FISH false positive case. The last had an IHC H-score of 200, 13% rearranged cells by FISH, and, thus is defined as a false negative FISH result. Provided IHC is defined as positive by an H-score above 120, all but one case (H-Score 20, FISH and RT-PCR positive) gave concordant results by a combination of FISH and RT-PCR. Overall, using as true negative or true positive the concordant result of two of the methods, the third method is characterized by high specificity and sensitivity with corresponding values of 100/98/100% and 94/94/89% for IHC/FISH/RT-PCR, respectively.

      Conclusion:
      RT-PCR is a very good tool for sorting discordant IHC/FISH cases, however, we do not recommend using this technique as single method due to the lower sensitivity of RT-PCR, as not all variants are covered, and also due to the limitations with RNA preservation.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.

    • +

      P3.04-053 - SPECTAlung: Screening Patients with Thoracic Tumors for Efficient Clinical Trial Access (ID 1386)

      09:30 - 17:00  |  Author(s): S.P. Finn

      • Abstract

      Background:
      The identification of molecular alteration and its targeting has completely changed the treatment and prognosis of lung cancer. However, designing and implementing clinical trials in small subsets of patients with a particular molecular alteration is challenging because of lack of uniform screening program. Across Europe, screening for molecular alterations is center or country dependent and, generally limited to a small subset of genes. SPECTAlung is the first European standardized, quality-assured molecular screening program of the European Organization for the Research and Treatment of Cancer (EORTC) in collaboration with the European Thoracic Oncology Platform (ETOP) to facilitate clinical trial access for patients with thoracic tumors. It is expected to test 500 to 1000 patients each year with the overall goal of offering patients clinical trials with targeted agents.

      Methods:
      Patients sign the informed consent for their tumor tissue to be collected, centralized and processed according to defined international quality control standards at Gustave Roussy Biobank (Villejuif, France). Next Generation Sequencing (NGS) is performed at Sanger Institute (Cambridge, UK) where a panel of about 360 genes is analyzed for mutation, rearrangements and gene copy number. Eligible patients will be those having a pathological diagnosis of any thoracic tumor (lung cancer, malignant pleural mesothelioma and thymic malignancies) at any stage of disease, availability of tumor tissue, age at least 18 years, PS 0-2, life expectancy > 3 months, no active malignancy in the 5 years before study entry and absence of any exclusion criteria that may prevent inclusion into clinical trials. A molecular report will be released to the investigator highlighting identified molecular alterations and also the trials for which the patients might be eligible. The study has been submitted to ethical committees of 15 selected highly specialized and qualified thoracic centres in 12 countries in Europe. EORTC and ETOP will promote the implementation of clinical trials in molecularly selected groups of patients at the SPECTAlung centers. SPECTAlung offers innovative and attractive models of collaboration with commercial and research organizations, by improving patient access to novel therapeutic clinical trial and support the development of personalized medicine. Clinical trial registry number NCT02214134.

      Results:
      Not applicable

      Conclusion:
      Not applicable

  • +

    P3.08 - Poster Session/ Thymoma, Mesothelioma and Other Thoracic Malignancies (ID 226)

    • Event: WCLC 2015
    • Type: Poster
    • Track: Thymoma, Mesothelioma and Other Thoracic Malignancies
    • Presentations: 1
    • +

      P3.08-008 - Tip60 (KAT5) May Be a Candidate for Therapeutic Targeting in Malignant Pleural Mesothelioma (ID 1760)

      09:30 - 17:00  |  Author(s): S.P. Finn

      • Abstract
      • Slides

      Background:
      Malignant pleural mesothelioma (MPM) is a rare aggressive cancer of the pleura. The most well established risk factor for this disease is exposure to asbestos. The current standard of care for patients suffering from MPM is a combination of cisplatin and pemetrexed (or alternatively cisplatin and raltitrexed). Most patients however, die within 24 months of diagnosis. New therapies are therefore urgently required for this disease. KAT5 (also known as Tip60) is the catalytic subunit of the NuA4 histone acetyltransferase complex which is involved in transcriptional activation of select genes. This complex may be required for the activation of transcriptional programs associated with oncogene and proto-oncogene mediated growth induction, tumor suppressor mediated growth arrest and replicative senescence, apoptosis, and DNA repair. KAT5 has also been linked with the development of cisplatin resistance. KAT5 may therefore be a significant element in MPM with respect to responses to cisplatin based therapy and could represent a novel candidate target for intervention.

      Methods:
      KAT5 has 4 variant mRNAs. Primers were designed to distinguish between all variants, and a panel of MPM cell lines was screened for KAT5 expression by RT-PCR. Levels of KAT5 were subsequently examined in a cohort of snap-frozen patient samples isolated at surgery comprising benign, epithelial, biphasic, and sarcomatoid histologies by RT-PCR. The effects of a small molecule inhibitor of KAT5 (MG-149) on cellular proliferation were examined.

      Results:
      Semi-quantitative densitometric analysis showed that the expression of KAT5 is dramatically increased in MPM for all mRNA variants. When separated according to histological subtype, significant differences were also observed between the various histologies. A small molecule inhibitor of KAT5 exists and treatment of cells with this small molecule inhibitor (MG-149) resulted in a significant inhibition of cellular proliferation (p < 0.001) in the NCI-H226 cell line. We continue to assess this compound by other methodologies to confirm its potential utility in the treatment of MPM.

      Conclusion:
      KAT5, a lysine acetyltransferase associated with cisplatin resistance in cancer is significantly altered in MPM. A small molecule inhibitor of this protein shows significant anti-proliferative effects in MPM cell lines. Targeting this protein may have important future implications for the management of MPM.

      Only Active Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login or select "Add to Cart" and proceed to checkout.