miR-1825, miR-484, miR-205, miR-141, and let-7b were shown to be highly specific for PCa, suggesting that they could be used as PCa tumor screening biomarkers. miR-205 may also be used as a biomarker for indicating bone metastasis in PCa patients, miR-1825 levels may help indicate tumor-node-metastasis classification, the evaluation of treatment effects, and determining prognosis, while let-7b levels may indicate potential tumor malignancy and the hormone resistance status and could be used as a basis to adjust individual treatments for the high-risk, early diagnosis of refractory PCa.
Enhanced Let7b expression reduced the proportion of cancer stem cell in liver cancer cell; meanwhile, Let7b inhibition increased the proportion of cancer stem cell.
The present study results demonstrated that let-7b increases drug sensitivity in chemotherapy‑resistant SGC7901/DDP and SGC7901/VCR gastric cancer cells by targeting the downregulation of c-Myc and that, let-7b mimic reverses MDR by promoting cancer stem cell differentiation controlled by double-negative autoregulatory loops (Lin28/let-7 and Myc/let-7) and a double-positive autoregulatory loop (Lin28/Lin28B/Myc) existing in GC cells, which remains to be confirmed.