Objective: To investigate the expression of elongation of very long-chain fatty acids family member 6 (ELOVL6) in high-grade serous ovarian carcinoma (HSOC), and explore the correlation between its expression and clinical prognosis in these patients.
Methods: The expression of ELOVL6 at mRNA and protein levels were respectively detected by reverse transcription (RT)-PCR and immune histochemistry method in 12 cases with normal ovarian tissues and 172 cases with HSOC from primary tumor site, forty of which had paired peritoneal metastatic tissues.
Results: (1) The results tested by RT-PCR showed that ELOVL6 expression in normal ovarian tissue was 4.8±1.1, while 1.2±0.7 in primary tumors and 1.8±0.9 peritoneal metastatic sites in HSOC. Compared with normal ovarian tissue, the level of ELOVL6 mRNA was significantly lower in HSOC (P<0.05). There was no significant difference between primary and peritoneal metastatic sites in HSOC (P=0.610). It was shown that ELOVL6 protein localized in cytoplasm of ovarian cancer cell by immunostaining assay. (2) ELOVL6 expression was observed in all normal ovarian tissue, 70.2% of G1-G2 and 48.8% of G3 HSOC (P<0.05). ELOVL6 expression in drug-resistant group were significantly lower than that in non-resistant group (39.1% vs 65.0%, P<0.01). The median disease-free survival was 41 months in the ELOVL6-positive group and 39 months in ELOVL6-negative group (P>0.05). The total median survival was 52 months in ELOVL6-positive group and 44 months in ELOVL6-negative group (P>0.05).
Conclusion: Low expression of ELOVL6 may correlate with the poor differentiation and drug resistance in HSOC.