No abstract

Hepatocellular carcinoma (HCC) is a major type of primary liver cancer and the sixth most prevalent human malignancies worldwide. However, the molecular mechanisms underlying hepatocarcinogenesis remain unclear. For HCC patients, there is not only a lack of effective therapeutic targets but also a lack of predictive or prognostic biomarkers. In this article, we reported that TRIM32 was obviously upregulated in HCC tumor tissues and HCC cell lines. Its expression patterns were positively correlated with histological grade, tumor sizes, and HBsAg of HCC patients. TRIM32 expression was a significant predictor for the overall survival time of HCC patients. Moreover, the overexpression of TRIM32 in cells accelerated the G1-S phase transition, promoted cell proliferation rates, and induced the resistance of HCC patients to oxaliplatin. All these findings suggest that TRIM32 might play important roles in the hepatocarcinogenesis. TRIM32 could be a novel direction to explore the mechanism underlying HCC pathogenesis.

The α2,3‐sialylation of N‐glycans is considered important but complicated because the functions of the three β‐galactoside α2,3‐sialyltransferases, ST3GAL3, ST3GAL4, and ST3GAL6, could be compensating for one another. To distinguish their specific functions, we established each individual knockout (KO) cell line. Loss of either the ST3GAL3 or ST3GAL6 genes decreased cell proliferation and colony formation, as opposed to the effect in the ST3GAL4 KO cells. The phosphorylation levels of ERK and AKT were significantly suppressed in the ST3GAL6 KO and ST3GAL3 KO cells, respectively. The cell aggregations were clearly observed in the KO cells, particularly the ST3GAL3 KO and ST3GAL6 KO cells, and the expression levels of E‐cadherin and claudin‐1 were enhanced in both those cell lines, but were suppressed in the ST3GAL4 KO cells. Those alterations were reversed with an overexpression of each corresponding gene in rescued cells. Of particular interest, the α2,3‐sialylation levels of β1 integrin were clearly suppressed in the ST3GAL4 KO cells, but these were increased in the ST3GAL3 KO and ST3GAL6 KO cells, whereas the α2,3‐sialylation levels of EGFR were significantly decreased in the ST3GAL6 KO cells. The decrease in α2,3‐sialylation increased the α2,6‐sialylation on β1, but not EGFR. Furthermore, a cross‐restoration of each of the three genes in ST3GAL6 KO cells showed that overexpression of ST3GAL6 sufficiently rescued the total α2,3‐sialylation levels, cell morphology, and α2,3‐sialylation of EGFR, whereas the α2,3‐sialylation levels of β1 were greatly enhanced by an overexpression of ST3GAL4. These results clearly demonstrate that the three α2,3‐sialyltransferases modify characteristic target proteins and regulate cell biological functions in different ways.

Abstract. ADP-ribosylation factor 1 (ARF1) is a small G protein that regulates many cellular processes such as reorganization of the actin cytoskeleton and is highly expressed in various tumor cells and tissues. However, the role of ARF1 in ovarian cancer progression remains unknown. In the present study, we explored the expression patterns of ARF1 in clinical ovarian cancer samples and adjacent noncancerous tissues. The results revealed that ARF1 overexpressed in EOC tissues and cell lines, compared with the adjacent non-tumorous tissues and normal ovarian cells. In addition, the immunoreactivity of ARF1 was positively correlated with EOC grade and Ki-67 expression. Knockdown of ARF1 expression notably inhibited cell proliferation and migration rate of EOC cells by the auxiliary of PI3K. Taken together, our findings provide new insights into the functional role of ARF1 on EOC cell growth and migration and it may serve as a diagnostic and therapeutic target.