Breast cancer (BC) in the Asia Pacific regions is enriched in younger patients and rapidly rising in incidence yet its molecular bases remain poorly characterized. Here we analyze the whole exomes and transcriptomes of 187 primary tumors from a Korean BC cohort (SMC) enriched in pre-menopausal patients and perform systematic comparison with a primarily Caucasian and post-menopausal BC cohort (TCGA). SMC harbors higher proportions of HER2+ and Luminal B subtypes, lower proportion of Luminal A with decreased ESR1 expression compared to TCGA. We also observe increased mutation prevalence affecting BRCA1, BRCA2, and TP53 in SMC with an enrichment of a mutation signature linked to homologous recombination repair deficiency in TNBC. Finally, virtual microdissection and multivariate analyses reveal that Korean BC status is independently associated with increased TIL and decreased TGF-β signaling expression signatures, suggesting that younger Asian BCs harbor more immune-active microenvironment than western BCs.

To elucidate the effects of neoadjuvant chemotherapy (NAC), we conduct whole transcriptome profiling coupled with histopathology analyses of a longitudinal breast cancer cohort of 146 patients including 110 pairs of serial tumor biopsies collected before treatment, after the first cycle of treatment and at the time of surgery. Here, we show that cytotoxic chemotherapies induce dynamic changes in the tumor immune microenvironment that vary by subtype and pathologic response. Just one cycle of treatment induces an immune stimulatory microenvironment harboring more tumor infiltrating lymphocytes (TILs) and up-regulation of inflammatory signatures predictive of response to anti-PD1 therapies while residual tumors are immune suppressed at end-of-treatment compared to the baseline. Increases in TILs and CD8+ T cell proportions in response to NAC are independently associated with pathologic complete response. Further, on-treatment immune response is more predictive of treatment outcome than immune features in paired baseline samples although these are strongly correlated.

Aberrant expression of miR-196a has been frequently reported in cancer studies. However, the expression and mechanism of its function in gastric cancer remains unclear. Quantitative real-time PCR was carried out to detect the relative expression of miR-196a in gastric cancer cell lines and tissues. SGC7901 cells were treated with miR-196a inhibitors, mimics, or pCDNA/miR-196a to investigate the role of miR-196a in cell proliferation. Higher expression of miR-196a in gastric cancer tissues was associated with tumor size, a higher clinical stage, and was also correlated with shorter overall survival of patients with gastric cancer. Exogenous downregulation of miR-196a expression significantly suppressed the in vitro cell-cycle progression, proliferation, and colony formation of gastric cancer cells, and ectopic miR-196a expression significantly enhanced the development of tumors in nude mice. Luciferase assays revealed that miR-196a inhibited p27 kip1 expression by targeting one binding site in the 3 0 -untranslated region (3 0 -UTR) of p27 kip1 mRNA. qPCR and Western blot assays verified that miR-196a reduced p27 kip1 expression at both mRNA and protein levels. The p27 kip1 -mediated repression in cell proliferation was reverted by exogenous miR-196a expression. A reverse correlation between miR-196a and p27 kip1 expression was noted in gastric cancer tissues. Our study shows that aberrant overexpression of miR-196a and consequent downregulation of p27 kip1 could contribute to gastric carcinogenesis and would be targets for gastric cancer therapies and further developed as potential prognostic factors.

Accumulating clinical evidence suggests that hyperuricemia is associated with an increased risk of type 2 diabetes. However, it is still unclear whether elevated levels of uric acid can cause direct injury of pancreatic β-cells. In this study, we examined the effects of uric acid on β-cell viability and function. Uric acid solution or normal saline was administered intraperitoneally to mice daily for 4 weeks. Uric acid-treated mice exhibited significantly impaired glucose tolerance and lower insulin levels in response to glucose challenge than did control mice. However, there were no significant differences in insulin sensitivity between the two groups. In comparison to the islets in control mice, the islets in the uric acid–treated mice were markedly smaller in size and contained less insulin. Treatment of β-cells in vitro with uric acid activated the NF-κB signaling pathway through IκBα phosphorylation, resulting in upregulated inducible nitric oxide synthase (iNOS) expression and excessive nitric oxide (NO) production. Uric acid treatment also increased apoptosis and downregulated Bcl-2 expression in Min6 cells. In addition, a reduction in insulin secretion under glucose challenge was observed in the uric acid–treated mouse islets. These deleterious effects of uric acid on pancreatic β-cells were attenuated by benzbromarone, an inhibitor of uric acid transporters, NOS inhibitor L-NMMA, and Bay 11–7082, an NF-κB inhibitor. Further investigation indicated that uric acid suppressed levels of MafA protein through enhancing its degradation. Collectively, our data suggested that an elevated level of uric acid causes β-cell injury via the NF-κB-iNOS-NO signaling axis.

This study demonstrates that increased FTO levels in the liver are involved in oxidative stress and lipid deposition, which characterize NAFLD.