Roux-en-Y Gastric Bypass Improves Hepatic Glucose Metabolism Involving Upregulation of Sirt1 in Type 2 Diabetes Mellitus.

BACKGROUND: Roux-en-Y gastric bypass (RYGB) is the most effective treatment for type 2 diabetes mellitus (T2DM). Previous studies have reported that silent information regulator 1 (Sirt1) closely relates to many pathological processes of glucose metabolism and insulin resistance (IR). However, it is unclear whether Sirt1 is involved in the hepatic glucose metabolism of T2DM after RYGB. METHODS: T2DM rats were randomly divided into four groups: Control, DM, Diet and RYGB. Normal rats were served as the control group. Hematoxylin and eosin (H&E) staining and Masson staining assays were performed to explore the changes of liver fibrous tissue after RYGB. The effect of RYGB on the protein expression of Sirt1 was detected by the Western blotting assay and immunohistochemical assay. Next, we built the insulin resistance model of human hepatocyte cell lines (FL62891 and HHL5) using the human recombinant insulin. Western blotting assay was applied to determine the expression of Sirt1 and the expression change of IRS1/mTOR2 /PKB pathway-related proteins in FL62891 and HHL5 cells. Additionally, the effects of Sirt1 on the expression of PTP1B and FGF-21 in insulin-resistant FL62891 and HHL5 cells were investigated using Western blotting and immunofluorescence assay. RESULTS: Our results showed that following RYGB improved the pathological changes of liver and increased the expression of Sirt1 in rats with T2DM compared with the diabetic rats. In experiments in vitro, the expression of Sirt1 was downregulated in insulin-resistance FL62891 and HHL5 cells. Moreover, overexpression of Sirt1 significantly increased the expression of FGF-21 whereas decreased the expression of PTP1B in insulin-resistance FL62891 and HHL5 cells. These above changes were alleviated in RYGB and Diet groups. Furthermore, RYGB could improve the glucose metabolism through activating IRS1/mTOR2/PKB pathways by regulating Sirt1 in rats with T2DM. CONCLUSION: RYGB could significantly improve hepatic glucose metabolism and increase the expression of Sirt1 in T2DM rats, which is related to the IRS1/mTOR2 /PKB pathway.

miR-20a/Foxj2 Axis Mediates Growth and Metastasis of Colorectal Cancer Cells as Identified by Integrated Analysis.

BACKGROUND MicroRNAs (miRNAs) have a significant regulatory effect on the proliferation, migration, and invasion of cells, and have been widely reported to have oncogenic or tumor-suppressive impacts on various tumors. In the present study we assessed the regulation and function of miR-20a on colorectal cancer (CRC) cell lines. MATERIAL AND METHODS qPCR was used to quantify miR-20a expression. Luciferase reporter assay was conducted to confirm Foxj2 3'UTR associations. In addition, the function of miR-20a and Foxj2 in CRC was detected using MTT, colony formation, transwell assays, and cell cycle analysis. RESULTS Our data revealed that miR-20a expression was elevated in the CRC cell lines, and cell migration, proliferation, and invasion abilities were promoted by the overexpression of miR-20a. Moreover, Foxj2 was authenticated as a direct target gene of miR-20a in CRC cells. Furthermore, we found that the ectopic Foxj2 dramatically suppressed miR-20a-promoted proliferation, migration, invasion, and xenografts in vitro and in vivo, and induced cell cycle arrest at G1 stage. CONCLUSIONS Our results showing the roles of miR-20a/Foxj2 in carcinogenesis of CRC may help improve treatment of CRC.

C-type lectins facilitate tumor metastasis.

Metastasis, a life-threatening complication of cancer, leads to the majority of cases of cancer-associated mortality. Unfortunately, the underlying molecular and cellular mechanisms of cancer metastasis remain to be fully elucidated. C-type lectins are a large group of proteins, which share structurally homologous carbohydrate-recognition domains (CRDs) and possess diverse physiological functions, including inflammation and antimicrobial immunity. Accumulating evidence has demonstrated the contribution of C-type lectins in different steps of the metastatic spread of cancer. Notably, a substantial proportion of C-type lectins, including selectins, mannose receptor (MR) and liver and lymph node sinusoidal endothelial cell C-type lectin, are important molecular targets for the formation of metastases in vitro and in vivo. The present review summarizes what has been found regarding C-type lectins in the lymphatic and hematogenous metastasis of cancer. An improved understanding the role of C-type lectins in cancer metastasis provides a comprehensive perspective for further clarifying the molecular mechanisms of cancer metastasis and supports the development of novel C-type lectins-based therapies the for prevention of metastasis in certain types of cancer.