FAK regulates Cdk2 in EGF-stimulated primary cultures of hepatocytes

TIMM50 promotes tumor progression via ERK signaling and predicts poor prognosis of non-small cell lung cancer patients

TIMM50 (Translocase of the inner mitochondrial membrane 50), also called TIM50, plays an essential role in mitochondrial membrane transportation. The existing literature suggests that TIMM50 may perform as an oncogenetic protein in breast cancer. However, the molecular mechanism, especially in human non-small cell lung cancer (NSCLC), is uncertain to date. In the present study, using immunohistochemistry, we found that TIMM50 expression significantly correlated with larger tumor size (P = 0.049), advanced TNM stage (P = 0.001), positive regional lymph node metastasis (P = 0.007), and poor overall survival (P = 0.001). Proliferation and invasion assay showed that TIMM50 dramatically promoted the ability of proliferation and invasion of NSCLC cells. Subsequent Western blotting results revealed that TIMM50 enhanced the expression of Cyclin D1 and Snail, and inhibited the expression of E-cadherin. Moreover, TIMM50 facilitated the expression of phosphorylated ERK and P90RSK. Incorporation of ERK inhibitor counteracted the upregulating expression of CyclinD1, and Snail, and downregulating expression of E-cadherin expression induced by TIMM50 overexpression. In conclusion, our data indicated that TIMM50 facilitated tumor proliferation and invasion of NSCLC through enhancing phosphorylation of its downstream ERK/P90RSK signaling pathway. We speculated that TIMM50 might be a useful prognosis marker of NSCLC patients.

C6orf106 accelerates pancreatic cancer cell invasion and proliferation via activating ERK signaling pathway

C6orf106 was highly expressed in lung and breast cancer, and proposed as clinicopathologic factor for the development of those types of cancer. However, its expression in pancreatic cancer and the mechanism that C6orf106 functions as an oncogene has not been confirmed. In the present study, we found that C6orf106 was also up-regulated in pancreatic cancer tissues and cell lines. Furthermore, C6orf106 expression was associated with advanced T stage (P = 0.010), positive regional lymph node metastasis (P = 0.012), and advanced TNM stage (P = 0.006). In vitro experiments also showed that C6orf106 served a tumor enhancer in pancreatic cancer, through increasing the expression of Snail, Cyclin D1 and Cyclin E1, and reducing the expression of E-cadherin via activating extracellular-signal-regulated kinase (ERK)- p90-kDa ribosomal S6 kinases (P90RSK) signaling pathway. The addition of ERK inhibitor PD98059 counteracted the upregulation of Snail, Cyclin D1 and Cyclin E1, and restored the expression of E-cadherin, which indicated that C6orf106 was an upstream factor of ERK signaling pathway. Taken together, the present study indicates that C6orf106 facilitates invasion and proliferation of pancreatic cancer cells, likely via activating ERK-P90RSK signaling pathway.

ZNF259 inhibits non-small cell lung cancer cells proliferation and invasion by FAK-AKT signaling

Background

Zinc finger protein 259 (ZNF259) is known to play essential roles in embryonic development and cell cycle regulation. However, its expression pattern and clinicopathological relevance remain unclear.

Materials and methods

A total of 114 lung cancer specimens were collected. The ZNF259 expression was measured between the lung cancer tissues and the adjacent normal lung tissues by immunohistochemical staining and Western blotting. Moreover, the correlation of ZNF259 expression with clinicopathological features was analyzed in 114 cases of lung cancer. Additionally, ZNF259 was depleted in the lung cancer cells in order to analyze its effect in the lung cancer.

Results

Immunohistochemical staining of 114 lung cancer specimens revealed significantly lower ZNF259 expression in lung cancer tissues than in adjacent normal lung tissues (53.5% vs 71.4%, P<0.001). In addition, ZNF259 downregulation was significantly associated with larger tumor size (P=0.001), advanced TNM stage (P=0.002), and positive lymph node metastasis (P=0.02). Western blotting of 20 paired lung cancer samples revealed lower ZNF259 protein levels in lung cancer tissues than in those of corresponding normal lung tissues (P=0.0032). Depletion of ZNF259 resulted in enhanced levels of p-FAK and p-AKT, CyclinD1, and MMP2, which in turn increased the proliferation and invasion of lung cancer cells. The effects of ZNF259 depletion were reversed by treatment with specific FAK or AKT inhibitors.

Conclusion

ZNF259 depletion is correlated with the development of non-small cell lung cancer (NSCLC) and serves as a predictor of adverse clinical outcome in NSCLC patients. The inhibitory effect of ZNF259 on proliferation and invasion can be attributed to downregulation of CyclinD1 and MMP2 via inactivation of the FAK-AKT pathway.

c-Met signaling in the development of tumorigenesis and chemoresistance: Potential applications in pancreatic cancer

Pancreatic ductal adenocarcinoma is the 4^th leading cause of cancer deaths in the United States. The majority of patients are candidates only for palliative chemotherapy, which has proven largely ineffective in halting tumor progression. One proposed mechanism of chemoresistance involves signaling via the mesenchymal-epithelial transition factor protein (MET), a previously established pathway critical to cell proliferation and migration. Here, we review the literature to characterize the role of MET in the development of tumorigenesis, metastasis and chemoresistance, highlighting the potential of MET as a therapeutic target in pancreatic cancer. In this review, we characterize the role of c-Met in the development of tumorigenesis, metastasis and chemoresistance, highlighting the potential of c-Met as a therapeutic target in pancreatic cancer.