Background/Aims: Natural compounds are a promising resource for anti-tumor drugs. Myricetin, an abundant flavonoid found in the bark and leaves of bayberry, shows multiple promising anti-tumor functions in various cancers. Methods: The cytotoxic, pro-apoptotic, and anti-metastatic effects of myricetin on prostate cancer cells were investigated in both in vitro and in vivo studies. Short-hairpin RNA knockdown of the proviral integration site for Moloney murine leukemia virus-1 (PIM1), pull-down and co-immunoprecipitation assays, and an intracellular Ca²⁺ flux assay were used to investigate the potential underlying mechanism of myricetin. ONCOMINE database data mining and immunohistochemical analysis of prostate cancer tissues were used to evaluate the expression of PIM1 and CXCR4, as well as the correlation between PIM1 and CXCR4 expression and the clinicopathologic characteristics and prognoses of prostate cancer patients. Results: Myricetin exerted selective cytotoxic, pro-apoptotic, and anti-metastatic effects on prostate cancer cells by inhibiting PIM1 and disrupting the PIM1/CXCR4 interaction. Moreover, PIM1 and CXCR4 were coexpressed and associated with aggressive clinicopathologic traits and poor prognosis in prostate cancer patients. Conclusion: These results offer preclinical evidence for myricetin as a potential chemopreventive and therapeutic agent for precision medicine tailored to prostate cancer patients characterized by concomitant elevated expression of PIM1 and CXCR4.

Myoepithelial cells play key roles in normal mammary gland development and in limiting pre-invasive to invasive breast tumor progression, yet their differentiation and perturbation in ductal carcinoma in situ (DCIS) are poorly understood. Here, we investigated myoepithelial cells in normal breast tissues ofBRCA1andBRCA2germline mutation carriers and in non-carrier controls, and in sporadic DCIS. We found that in the normal breast of non-carriers, myoepithelial cells frequently co-express the p63 and TCF7 transcription factors and that p63 and TCF7 show overlapping chromatin peaks associated with differentiated myoepithelium-specific genes. In contrast, in normal breast tissues ofBRCA1mutation carriers the frequency of p63⁺TCF7⁺myoepithelial cells is significantly decreased and p63 and TCF7 chromatin peaks do not overlap. These myoepithelial perturbations in normal breast tissues ofBRCA1germline mutation carriers may play a role in their higher risk of breast cancer. The fraction of p63⁺TCF7⁺myoepithelial cells is also significantly decreased in DCIS, which may be associated with invasive progression.

Sorafenib is a multi-kinase blocker and one of the few suggested drug treatments for aggressive hepatocellular carcinoma (HCC) patients. However, drug resistance to sorafenib may often occur over time and cause further tumor aggression. Recently, cancer stem cells were found in HCC and were speculated to be involved in tumor progression. SOX9 is highly expressed in HCC cancer stem cells and promotes cell proliferation and self-renewal. Meanwhile, HCC patients with higher SOX9 expression show poorer prognosis. Whether SOX9 is involved in sorafenib resistance in HCC is still unclear. Here, we found that sorafenib treatment increased the proportion of SOX9 positive cells in HCC cell lines. Overexpression of exogenous SOX9 in HCC increased sorafenib resistance both in vitro and in vivo, whereas down-regulation led to inhibition of sorafenib resistance. Knock-down of SOX9 by RNA interference caused down-regulation of downstream genes, including ATP binding cassette subfamily G member 2 (ABCG2). The drug resistance to sorafenib caused by SOX9 overexpression could be ameliorated by ABCG2 inhibition in HCC cell lines. In the cohort of patients taken sorafenib, we found that patients with lower SOX9 expression had more prolonged overall survival (OS) and progression-free survival (PFS). Univariate and multivariate Cox analysis shows that SOX9 expression exerts as an independent risk factor for the OS and PFS of HCC patients with sorafenib treatment. These findings demonstrate that SOX9 enhances sorafenib resistance and may regulate this process by modulating ABCG2 expression.

Aim: There is little knowledge about the expression profile and function of circular RNAs (circRNAs) in prostate cancer (PCa). Methods: The expression profiles of circRNAs in RWPE-1, 22RV1 and PC3 ... Lay abstract The expression profile and role of circular RNAs (circRNAs) in prostate cancer (PCa) is unknown. In this study, the profiling of circRNAs in PCa cells was explored and their potential ...

Induced hepatic stem cells (iHepSCs) have great potential as donors for liver cell therapy due to their self‐renewal and bipotential differentiation properties. However, the efficiency of bidifferentiation and repopulation efficiency of iHepSCs is relatively low. Recent evidence shows that physiological hypoxia, a vital factor within stem cell “niche” microenvironment, plays key roles in regulating tissue stem cell biological behaviors including proliferation and differentiation. In this study, we found that physiological hypoxia (10% O₂) enhanced the stemness properties and promoted the proliferation ability of iHepSCs by accelerating G1/S transition via p53‐p21 signaling pathway. In addition, short‐term hypoxia preconditioning improved the efficiency of hepatic differentiation of iHepSCs, and long‐term hypoxia promoted cholangiocytic differentiation but inhibited hepatic differentiation of iHepSCs. These results demonstrated the potential effects of hypoxia on stemness preservation, proliferation, and bidifferentiation of iHepSCs and promising perspective to explore appropriate culture conditions for therapeutic stem cells.