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T. Prieto



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    P1.04 - Poster Session/ Biology, Pathology, and Molecular Testing (ID 233)

    • Event: WCLC 2015
    • Type: Poster
    • Track: Biology, Pathology, and Molecular Testing
    • Presentations: 1
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      P1.04-008 - Tissue Hyaluronan and Its Relationship with Angiogenesis Are Indicators of Lung Cancer Malignancy (ID 1049)

      09:30 - 17:00  |  Author(s): T. Prieto

      • Abstract

      Background:
      Cell-extracellular matrix interactions participate in several steps required for tumor cell invasion and because of that, a group of glycosaminoglycans have been targeted as potentially useful tumor markers. Hyaluronan has shown promise, but still there is uncertainty about its localization in tumor tissue and its relationship with histological types and angiogenesis. Regarding that, we evaluated the association between HA and degree of malignancy through its expression in lung tumor tissue and association with angiogenesis.

      Methods:
      Forty-six lung specimens were evaluated. Hyaluronan and microvessel (CD34) quantification in situ was done in FFPE sections of nonneoplastic cells, lung cancer cells, and tumor stroma. Colocation was evaluated in tumor stroma using confocal microscopy. Cox proportional hazards model, MantelHaenszel test and Pearson’s x2 were used to evaluate the hyaluronan and microvessel staining inferences and the relationship between them.

      Results:
      Squamous cell carcinoma showed abundant hyaluronan on the cancer cell-stroma interface coincident with prominent microvessel staining and identical colocalization at confocal microscopy. Strong hyaluronan staining associated with cancer cells was significant in 32.1% of squamous cell carcinoma compared to 17.9% of adenocarcinoma and 0.0% in large cell carcinoma (P<0.001). Adenocarcinomas revealed strong stromal hyaluronan staining in contrast with the hyaluronan-poor tumor cells. The foci of hyaluronan stromal staining was coincident with foci of microvessel and colocalization. Furthermore, adenocarcinoma more often showed a lower percentage of hyaluronan-positive cancer cells (35.7% of cases) than large cell carcinoma (14.3% of cases) or squamous cell carcinoma (0% of cases; P<0.001). For large cell carcinoma, the hyaluronan signal in tumor cells was very poor and contrasted with the foci of staining in stroma, coincident with focal microvessel density and colocalization. All these results are shown in Figure 1. A significant direct association was found between tumors with a high percentage of HA and MVD in tumor stroma (R=0.6; P=0.02). Similarly significant was the direct association between tumors at the N1 stage and high levels of hyaluronan in cancer cells (R=0.31; P=0.05). In addition, tumors in the T4 stage presented positive association with a high percentage of hyaluronan-positive cancer cells (R=0.80; P=0.01).Figure 1



      Conclusion:
      Our findings showed that an elevated hyaluronan signal in tumor cells was associated with poor prognosis and its localization relationship with histological types and angiogenesis was related to malignancy of lung cancer. To realize these findings a greater larger scale study in a randomized trial will be required.

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

    • Event: WCLC 2015
    • Type: Poster
    • Track: Biology, Pathology, and Molecular Testing
    • Presentations: 1
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      P3.04-088 - Matrix Proteoglycans Gene Expression Predicts Lung Cancer Patients Outcome (ID 1463)

      09:30 - 17:00  |  Author(s): T. Prieto

      • Abstract

      Background:
      The relationship between the extracellular matrix (ECM) components and cancer cells have an important role on cancer development and progression. Between the most important molecules present on the ECM are the glycosaminoglycans(GAGs) and their respective proteoglycans (PGs). Studies have reported that they have different behaviours when in the presence of malignant tissues.The aim of this study was to analyse PGs gene expression in normal and tumoral areas of patients with lung cancer (LC) and to explore its association with GAGs concentration.

      Methods:
      Eighty-seven lung specimens were evaluated. Biglycan, glypican, perlecan, syndecan and versican gene expression were analysed by qRT-PCR and sulfated GAG chains(heparan, dermatan and chondroitin sulfate - HS, DS and CS)were obtained after incubation with a proteolytic enzyme.GAGs were precipitated with ethanol and the pellet was centrifugated, dried and dissolved in DNAse(5 l/mg).The different types of sulfated GAGs and their concentration in the lung samples were identified after gel electrophoresis in diaminopropane buffer. Statistical analyses included ANOVA, Paired-samples T Test, Spearman correlation, and logistic regression.

      Results:
      A significant increase of biglycan was found in tumor tissue compared to normal (52.30 ± 21.2 vs 11.28 ± 3.77; p=0.04). A significant association was found between biglycan vs glypican (R= 0.64; P<0.01), biglycan vs perlecan (R=0.70; P<0.01) and biglycan vs versican (R=0.68; P<0.01). Univariate analysis demonstrated that high expression of tumoral biglycan significantly related to squamous cell carcinoma histologic type (P=0.02) and death (P=0.03). Equally significant was the association between high syndecan expression, tobacco history (P<0.01) and tumoral recurrence (P=0.04). Logistic regression analysis controlled for age, gender, Tstage, Nstage, histologic types and proteoglycans expression showed that higher biglycan expression was and independent predictor of death [OR= 1.44 (0.88-2.36)]. Those with higher relative expression of biglycan had a high risk for death. In addition, we found that biglycan and glypican gene expression related significantly to tumoral heparan sulphate concentration in tumoral tissue (R=0.38; P=0.04 and R=0.41; P=0.03).

      Conclusion:
      Different expression of PGs in lung cancer samples, its relationship with histologic types and death suggest a possible role of these PGs in this malignancy, but more importantly provide a potential biomolecular marker to predict outcome.The correlation between the histologic types and the expression of biglycan provide a possible role of this PG on the development of tumor agressiveness considering that one of its functions is to bind itself to growth factors and regulate their action. Moreover, the relationship between heparan sulphate concentration, biglycan and glypican gene expression might indicate what sort of PGs are produced by tumoral tissue considering that heparan sulphate is the GAG chain in these PGs. Further studies are needed to determine whether or not these PGs gene expression are able to be predict prognosis and tumoral aggressiveness.