These results suggest that molecular subtypes of the LIN-28B/let-7a/IGF-II axis associate with heterogeneous progression and may have clinical implications in predicting epithelial ovarian cancer prognosis.
Using new 65 controls and 224 EOC patients (thereof 14 FIGO I/II) the abundances of six plasma proteins (MIF, prolactin, CA125, leptin, osteopondin, and IGF2) was determined and used in combination with the expression values from the 13 genes for diagnosis of EOC.
We found no association between variation in IGF1, IGFBP1 or IGFBP3 and risk of invasive disease, whereas five tSNPs in IGF2 were associated with risk of invasive epithelial ovarian cancer at P<0.05 and followed-up one of the associated SNPs.
To further understand the role of lin-28 in cancer, we analysed the expression of lin-28 and its homologue lin-28B in tumour samples, and evaluated their associations with let-7a maturation, IGF-II expression, disease features and outcomes in 211 patients with primary epithelial ovarian cancer.
Using real-time methylation-specific PCR and real-time reverse transcription-PCR, we analyzed DNA methylation in the let-7a-3 gene and miRNA expression of let-7a in 214 patients with epithelial ovarian cancer to assess the effect of let-7a-3 methylation on the expressions of let-7a as well as a possible target of let-7 regulation, insulin-like growth factor-II (IGF-II).
High insulin-like growth factor-2 (IGF-2) gene expression is an independent predictor of poor survival for patients with advanced stage serous epithelial ovarian cancer.