SUV39H1, the histone methyltransferase (HMTase) of histone H3 lysine 9 trimethylation (H3K9me3), is a known transcriptional repressor of inflammatory genes. The effect of SUV39H1 on inflammatory gene promoters under high-glucose stimulation in vascular smooth muscle cells (VSMCs), macrophages, and cardiomyocytes has been studied, but how SUV39H1 functions in renal tubules under diabetic conditions is unclear. Renal biopsy specimens of ten diabetic nephropathy (DN) subjects and seven non-DN minimal change diseases (MCD) subjects were collected. SUV39H1, IL-6, and MCP-1 expression in renal tissues were measured using immunohistochemical, while SUV39H1, H3K9me3, IL-6, and MCP-1 in human proximal tubular epithelial cells (HK-2) under varying glucose conditions were assayed by Western blot and ELISA. SUV39H1 was overexpressed in HK-2 cells; the regulation of SUV39H1 and H3K9me3 on NF-κB, IL-6, MCP-1, caspase 3, and apoptosis was measured. SUV39H1 was expressed more in diabetic human renal tubules. HK-2 cells with high glucose up-regulated IL-6 and MCP-1 in a dose- and time-dependent manner, and SUV39H1 expression was reduced with greater glucose and prolonged stimulation. Expression of H3K9me3 was synchronized with SUV39H1. Moreover, overexpression of SUV39H1 in high glucose environment was accompanied with increased H3K9me3 and decreased inflammation and apoptosis. SUV39H1 dysregulation may be involved in DN progression. Overexpression of SUV39H1 may reduce renal inflammation and apoptosis via epigenetic modulation, thus plays a protective role in DN.

This result suggested that OPN plays an important role in Ang II-induced inflammatory activation in VSMCs. The finding further supports OPN as a potential target for atherosclerotic therapy.

It is significant to develop a probe with sensitivity and specificity for the detection of cancer cells. The present study aimed to develop an ‘activatable’ aptamer-based fluorescence probe (AAFP) to detect cancer cells and frozen cancer tissue. This AAFP consisted of two fragments: aptamer TLS11a that targets HepG2 cells, and two short extending complementary DNA sequences with a 5′- and 3′-terminus that make the aptamer in hairpin structure a capable quencher to fluorophore. The ability of the AAFP to bind specifically to cancer cells was assessed using flow cytometry, fluorescence spectroscopy and fluorescence microscopy. Its ability to bind to frozen cancer tissue was assessed using fluorescence microscopy. As a result, in the absence of cancer cells, AAFP showed minimal fluorescence, reflecting auto-quenching. In the presence of cancer cells, however, AAFP showed a strong fluorescent signal. Therefore, this AAFP may be a promising tool for sensitive and specific detection of cancer.

Uncontrolled proliferation is the hallmark of cancer cells. Previous studies mainly focused on the role of protein-coding genes in cancer cell proliferation. Emerging evidence showed that long non-coding RNAs (lncRNAs) also play critical roles in cancer cell proliferation and growth. LncRNA KCNQ1OT1 is found to contribute to carcinogenesis, but its role in acute promyelocytic leukemia (APL) is unclear. In this study, by analyzing data from Gene Expression Omnibus, The Cancer Genome Atlas database and our clinical samples, we found that KCNQ1OT1 was selectively highly expressed in APL. Functional assays demonstrated that knockdown of KCNQ1OT1 reduced APL cell proliferation and increased apoptosis. Further evidence showed that KCNQ1OT1 was mainly located in the cytoplasm of APL patient-derived NB4 cells and APL patient bone marrow samples. Mechanistically, KCNQ1OT1 bound to RNA binding protein FUS, and silencing either KCNQ1OT1 or FUS reduced the expression level and stability of MAP3K1 mRNA. Whereas KCNQ1OT1 and FUS did not affect each other. Importantly, knockdown of MAP3K1 impaired APL cell proliferation. Finally, c-Myc transactivated KCNQ1OT1 in APL cells through binding to its promoter while knockdown of c-Myc decreased KCNQ1OT1 expression. Our results not only revealed that c-Myc transactivated KCNQ1OT1 and upregulated KCNQ1OT1 promoted APL cell proliferation, but also demonstrated that KCNQ1OT1 bound to FUS to synergistically stabilize MAP3K1 mRNA, thus facilitating APL cell proliferation. This study established a previously unidentified role of KCNQ1OT1 in the development of APL, and KCNQ1OT1 may serve as a potential therapeutic target for APL.