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FTY720, a synthetic compound produced by modification of a metabolite from Isaria sinclairii, is known as a unique immunosuppressive agent that exerts its activity by inducing apoptosis of lymphocytes [S. Suzuki, FTY720: Mechanisms of action and its effect on organ transplantation, Transplant. Proc. 31 (1999) 2779-2782]. Additionally, it has been found that FTY720 has inhibitory effects on various cancer growth and metastasis [J.D. Wang, S. Takahara, N. Nonomura, Early induction of apoptosis in androgen-independent prostate cancer cell line by FTY720 requires caspase-3 activation, Prostate 40 (1999) 50-55]. To investigate its effect on the growth and metastasis of pancreatic cancer, FTY720 was used to treat three pancreatic cancer cell lines (BxPC-3, AsPC-1, and PANC-1). The MTT assay and flow cytometry were used to evaluate the cell death after FTY720 treatment; the wound closure assay, three-dimensional (3D) Matrigel assay, and invasive assay were used to evaluate the migration, colony formation and invasion abilities after FTY720 treatment, respectively. Protein expression in BxPC-3, AsPC-1, and PANC-1 cells after FTY720 treatment was detected by Western blotting. The MTT assay indicated that the growth of pancreatic cancer cells could be inhibited by FTY720 at various concentrations between 0 and 17 microM in a dose-dependent manner, which was also confirmed by flow cytometry. The wound closure assay, 3D Matrigel assay and cell invasion assay all showed that FTY720 significantly suppressed migration, colony formation and invasion ability of cancer cells at concentrations from 5 to 17 microM. After FTY720 treatment, the phospho-Akt, Bcl-2, pro-caspase-3 expression were down-regulated while the caspase-9 protein expression was increased. In conclusion, FTY720 can inhibit the growth, migration and invasion of pancreatic cancer cells. Our study provides a preclinical support for chemotherapeutic approach with FTY720 for the treatment of pancreatic cancer.

In early studies, it was shown that HINT2, which sensitizes cells to mitochondrial apoptosis, is down-regulated in hepatocellular carcinoma (HCC) cells (Martin et al., 2006). However, the molecular mechanism of this effect is unknown. Immunohistochemistry revealed that HINT2 expression is relatively low in pancreatic cancer tissues, compared to that in adjacent tissues (P < 0.05). Furthermore, its expression was related to pathological grade and lymph node metastasis (P = 0.0161 and 0.0108, respectively); in addition, down-regulation of HINT2 was found to be associated with relatively poor prognosis in pancreatic cancer patients. Up-regulation of HINT2 was shown to trigger pancreatic cancer cell apoptosis, decrease mitochondrial membrane potential (ΔΨm), promote intracellular reactive oxygen species (ROS) production, and elevate mitochondrial Ca2+ levels. However, co-treatment of HINT2 overexpressing BxPC-3 cells with ruthenium red partially inhibited HINT2-induced apoptosis, which was associated with a reduction in ΔΨm and an increase in intracellular ROS and mitochondrial Ca2+. According to our results, mitochondrial calcium uptake1 and 2 (MICU1 and MICU2) were down-regulated and the essential MCU regulator (EMRE) was up-regulated in cells transduced with Adv-HINT2. Therefore, we deduced that HINT2 triggers apoptosis in pancreatic cancer cells by regulating mitochondrial Ca2+ influx through the mitochondrial calcium uniporter (MCU). In addition, we found that HINT2 can sensitize BxPC-3 and L3.6pl cells to gemcitabine-induced apoptosis and that gemcitabine up-regulates HINT2 expression. This indicates that gemcitabine-induced apoptosis is related to HINT2 levels. [ABSTRACT FROM AUTHOR]

Pseudogenes are a subclass of long non-coding (lnc) RNAs that arose from protein-coding genes, but have lost the ability to produce proteins. Pseudogenes play an important role in the pathogenesis of various tumors; however, the role of pseudogenes in hepatocellular carcinoma (HCC) is poorly understood. In this study, we investigated a novel pseudogene, PDIA3P1, which was upregulated in HCC tissues compared with paired normal adjacent tissues. The expression of PDIA3P1 was significantly correlated with tumor size, metastasis, TNM stage, and overall stage. Knockdown of PDIA3P1decreased proliferation, migration, and invasion of HCC cells. PDIA3P1 knockdown also promoted cell apoptosis and inhibited tumor growth in vivo. We performed a GeneChip assay to investigate the underlying mechanism of PDIA3P1 action on biological function, and our results suggested that PDIA3P1 may promote proliferation and inhibit apoptosis of liver cancer cells by inhibiting the p53 pathway. Thus, our data suggest that PDIA3P1 acts as an oncogene in HCC and could be a potential prognostic marker and therapeutic target for HCC. [ABSTRACT FROM AUTHOR]

The transcriptional coactivator with PDZ binding motif (TAZ) is reported as one of the nuclear effectors of Hippo-related pathways. TAZ is found overexpressed in many primary tumors and could regulate many biological processes. However, little is known about the role of TAZ in Intrahepatic Cholangiocarcinoma (ICC). In this study, we found that TAZ is expressed more in ICC tissues than in peritumoral tissue, and a robust expression of TAZ is correlated with a lower overall survival rate of ICC patients after hepatectomy. TAZ knockdown results in an increase in cell apoptosis, a promotion of cell-cycle arrest and a decrease in tumor size and weight in vivo through an increased expression of p53. Vitamin D3 can also inhibit cell proliferation by promoting p53 expression in ICC cells. A reduction in TAZ can also enhance the sensitivity of tumor cells to vitamin D by regulating the p53/CYP24A1 pathway. In conclusion, TAZ is associated with the proliferation and drug-resistance of ICC cells, and could be a novel therapeutic target for the treatment of ICC. [ABSTRACT FROM AUTHOR]

In previous studies, we confirmed that mitofusin-2 (Mfn2) induced apoptosis in hepatocellular carcinoma (HCC) cells. However, the exact molecular mechanism remained unclear. Mfn2 expressed lower in tumour tissues, compared with adjacent non-cancer tissues. Furthermore, Mfn2 immunostaining was very weak in HCC tissue (P < 0.05) and was significantly associated with tumour size and TNM stage (P = 0.038 and 0.040, respectively), and patients with HCC with lower Mfn2 expression had a poorer prognosis. Overexpression of Mfn2 induced HepG2 cells apoptosis, reduced the mitochondrial membrane potential (ΔΨm) and endoplasmic reticulum (ER) calcium ion (Ca 2+ ) concentrations, and elevated intracellular reactive oxygen species (ROS) and mitochondrial Ca 2+ concentrations. However, when HepG2 cells overexpressing Mfn2 were treated with both heparin and RU360, there was no induction of apoptosis, decline in ΔΨm or ER Ca 2+ , or increase in intracellular ROS or mitochondrial Ca 2+ . We also found downregulation in the expression of mitochondrial calcium uptake1 and 2 (MICU1 and MICU2) in cells transfected with Adv-Mfn2. Thus, we confirmed that Mfn2 induced apoptosis in HCC cells by triggering influx of Ca 2+ into the mitochondria from the ER. [ABSTRACT FROM AUTHOR]