[Effect of Met kinase inhibitor BMS-777607 on proliferation and apoptosis of tongue cell line CAL 27 squamous cell carcinoma].

PURPOSE: To investigate the effect of Met kinase inhibitor BMS-777607 on proliferation and apoptosis of tongue squamous cell carcinoma cell line CAL27. METHODS: The effect of BMS-777607 on proliferation of CAL27 was detected by MTT method, clone formation assay and EdU cell imaging. Morphological changes of apoptosis of CAL27 cells induced by BMS-777607 were observed by Heochst33342 staining. JC-1 staining was used to detect the changes of mitochondrial membrane potential of CAL27 cells treated with BMS-777607. Western blot was used to detect the effect of BMS-777607 on the expression of proliferation protein Akt, p-Akt and apoptosis-related proteins Bcl-2, Cleaved caspase-3, Bax and Parp in CAL27 cells. The data were analyzed using SPSS 22.0 software package. RESULTS: BMS-777607 inhibited proliferation and promoted apoptosis of CAL27 cells in a concentration-dependent manner（P＜0.05）. It also inhibited the expression of Bcl-2 and p-Akt and promoted the expression of Bax, Cleaved caspase-3 and Parp protein (P＜0.05). CONCLUSIONS: BMS-777607 can inhibit proliferation and promote apoptosis of CAL27 cells.

[Effect of enhancer of zeste homolog 2 inhibitor GSK126 on the proliferation and apoptosis of tongue squamous cell carcinoma].

OBJECTIVE: This study aims to study the effect of the enhancer of zeste homolog 2 (EZH2) inhibitor GSK126 on the proliferation and apoptosis of human tongue squamous cell carcinoma cells in vitro and explore its related mechanisms in order to obtain insights into the clinical treatment of tongue squamous cell carcinoma. METHODS: Different concentrations of GSK126 were applied to CAL-27 cells of tongue squamous cell carcinoma, and the effects of drugs on cell proliferation were detected through methyl thiazolyl tetrazolium (MTT) assay, colony formation assay, and 5-ethynyl-2'-deoxyuridine (EdU) fluorescence staining. Hoechst33342 fluorescence staining and the JC-1 method were used in observing apoptosis. The expression levels of extracellular regulated protein kinases (ERK), phospho-extracellular regulated protein kinases (p-ERK), Bax, Bcl-2, and Cleaved caspase-9 in Cal-27 cells were detected through Western blot. RESULTS: GSK126 inhibited CAL-27 cell proliferation and promoted apoptosis. GSK126 down-regulated the expression of p-ERK and Bcl-2 and increased the expression of Bax and Cleaved caspase-9 (P<0.05). CONCLUSIONS: GSK126 can inhibit the proliferation of CAL-27 cells in tongue squamous cell carcinoma and promote its apoptosis, and the related mechanism may be associated with the inhibition of the MEK/ERK signaling pathway and activation of the Bax/Bcl-2 pathway.

BTG1 might be employed as a biomarker for carcinogenesis and a target for gene therapy in colorectal cancers.

Here, BTG1 overexpression inhibited proliferation, induced differentiation, autophagy, and apoptosis in colorectal cancer cells (p<0.05). BTG1 overexpression reduced mitochondrial membrane potential and caused senescence in HCT-116 transfectants (p<0.05). BTG1-induced G2 arrest might be related to Cyclin B1 and Cdc25B hypoexpression in HCT-15 transfectants, while G1 arrest in HCT-116 transfectants overexpressing p21 and p27. BTG1 overexpression decreased the expression of Bcl-2, Bcl-xL, XIAP, Akt1 or survivin and increased the expression of Bax or p53 in colorectal cancer cells. BTG1-induced autophagy was dependent on Beclin-1 expression. BTG1 overexpression might weaken ß-catenin pathway in colorectal cancer cells. The chemosensitivity of BTG1 transfectants to paclitaxel, cisplatin, MG132 or SAHA was positively correlated with its apoptotic induction. There was a lower expression level of BTG1 in cancer than matched non-neoplastic mucosa by RT-PCR (p<0.05), while versa for Western blot and immunohistochemical data (p<0.05). BTG1 overexpression significantly suppressed the growth of HCT-15 and HCT-116 via inhibiting proliferation, inducing apoptosis and autophagy in nude mice. Up-regulated BTG1 expression plays an important role in colorectal carcinogenesis as a potential biomarker. BTG1 expression might reverse aggressive phenotypes, so it might be employed as a target of gene therapy for colorectal cancer.

Opposite Effects of Two-Derived Antioxidants from Physalis pubescens L. on Hepatocellular Carcinoma Cell Line Malhavu.

Physalis pubescens L. (P. pubescens) is an edible plant used in folk medicine in China. There is traditional, but not scientific, evidence for the anti-tumour effects of P. pubescens. This study aimed to identify whether, or not, antioxidants rich in phenols and flavonoids from fruits and calyxes of P. pubescens can be the candidates for further development of an anti-hepatoma fraction, and if such biological effects coupled with reactive oxygen species (ROS) changes, can provide a direction for subsequent biological action. The effects of calyx-origin (or fruit-origin) total phenol and flavonoid (CTPF or FTPF) from P. pubescens on Malhavu cell viability were evaluated by using a counting-kit-8 (CCK-8) method. Morphological characterisation of cells was undertaken and the structures were photographed (200 × magnification) using Hoechst 3348 staining after exposure to different concentrations of CTPF or FTPF. Induced-apoptosis activity was determined using flow cytometry (FC) after Annexin VFITC/ PI staining. The corresponding ROS changes in Malhavu cells were observed and quantified by the uploading of 2', 7'-dichlorofluorescin diacetate (DCFH-DA). Anti-oxidation was evaluated by a cellular oxidation-stress model and chemical assessments for DPPH, hydroxyl radial, super-oxide radicals, and reducing power. Result shows that CTPF led to significant anti-proliferation in a time- and dosedependent manner. However, FTPF promoted cell viability at 100-1000 µg/mL with a dose-response manner in 24 h. With the extension of exposure time to 48 h, the cell viability did not increase with the growth of FTPF. Morphological characterisation and FC assay both demonstrated that CTPF, and not FTPF possessed induced-apoptotic activity. CTPF potentially induced cell apoptosis by promoting oxidative stress. FTPF indicated pro-oxidation at a concentration of 10 µg/mL and anti-oxidation capabilities at higher concentrations. ROS scavenging assay by oxidation-stress model indicated that CTPF (10 - 400 µg/mL) had ROS inhibitory capacity (R2 = 0.5156, p < 0.0001). FTPF (10 - 100 µg/mL) boosted the level of ROS (p < 0.0001) and inhibited the generation of ROS at 100-400 µg/mL (R2 = 0.5951, p < 0.0001). CTPF is a potential candidate requiring further exploration for the development of antihepatoma ingredients. The down-regulation of cell viability was related to production and reduction of cellular ROS.

The down-regulated ING5 expression in lung cancer: a potential target of gene therapy.

ING5 can interact with p53, thereby inhibiting cell growth and inducing apoptosis. We found that ING5 overexpression not only inhibited proliferation, migration, and invasion, but also induced G2 arrest, differentiation, autophagy, apoptosis, glycolysis and mitochondrial respiration in lung cancer cells. ING5 transfection up-regulated the expression of Cdc2, ATG13, ATG14, Beclin-1, LC-3B, AIF, cytochrome c, Akt1/2/3, ADFP, PFK-1 and PDPc, while down-regulated the expression of Bcl-2, XIAP, survivin,ß-catenin and HXK1. ING5 transfection desensitized cells to the chemotherapy of MG132, paclitaxel, and SAHA, which paralleled with apoptotic alteration. ING5 overexpression suppressed the xenograft tumor growth by inhibiting proliferation and inducing apoptosis. ING5 expression level was significantly higher in normal tissue than that in lung cancer at both protein and mRNA levels. Nuclear ING5 expression was positively correlated with ki-67 expression and cytoplasmic ING5 expression. Cytoplasmic ING5 expression was positively associated with lymph node metastasis, and negatively with age, lymphatic invasion or CPP32 expression. ING5 expression was different in histological classification: squamous cell carcinoma > adenocarcinoma > large cell carcinoma > small cell carcinoma. Taken together, our data suggested that ING5 downregulation might involved in carcinogenesis, growth, and invasion of lung cancer and could be considered as a promising marker to gauge the aggressiveness of lung cancer. It might be employed as a potential target for gene therapy of lung cancer.

GRP78 confers the resistance to 5-FU by activating the c-Src/LSF/TS axis in hepatocellular carcinoma.

5-FU is a common first-line chemotherapeutic drug for the treatment of hepatocellular carcinoma. However the development of acquired resistance to 5-FU confines its clinical usages. Although this phenomenon has been the subject of intense investigation, the exact mechanism of acquired resistance to 5-FU remains elusive. Here, we report that over-expression of GRP78 contributes to acquired resistance to 5-FU in HCC by up-regulating the c-Src/LSF/TS axis. Moreover, we found that the resistance to 5-FU conferred by GRP78 is mediated by its ATPase domain. The ATPase domain differentially increased the expression of LSF, TS and promoted the phosphorylation of ERK and Akt. We further identified that GRP78 interacts physically with c-Src through its ATPase domain and promotes the phosphorylation of c-Src, which in turn increases the expression of LSF in the nucleus. Together, GRP78 confers the resistance to 5-FU by up-regulating the c-Src/LSF/TS axis via its ATPase domain.

BTG1 expression correlates with pathogenesis, aggressive behaviors and prognosis of gastric cancer: a potential target for gene therapy.

Here, we found that BTG1 overexpression inhibited proliferation, migration and invasion, induced G2/M arrest, differentiation, senescence and apoptosis in BGC-823 and MKN28 cells (p < 0.05). BTG1 transfectants showed a higher mRNA expression of Cyclin D1 and Bax, but a lower mRNA expression of cdc2, p21, mTOR and MMP-9 than the control and mock (p < 0.05). After treated with cisplatin, MG132, paclitaxel and SAHA, both BTG1 transfectants showed lower mRNA viability and higher apoptosis than the control in both time- and dose-dependent manners (p < 0.05) with the hypoexpression of chemoresistance-related genes (slug, CD147, GRP78, GRP94, FBXW7 TOP1, TOP2 and GST-π). BTG1 expression was restored after 5-aza-2'-deoxycytidine treatment in gastric cancer cells. BTG1 expression was statistically lower in gastric cancer than non-neoplastic mucosa and metastatic cancer in lymph node (p < 0.05). BTG1 expression was positively correlated with depth of invasion, lymphatic and venous invasion, lymph node metastasis, TNM staging and worse prognosis (p < 0.05). The diffuse-type carcinoma showed less BTG1 expression than intestinal- and mixed-type ones (p < 0.05). BTG1 overexpression suppressed tumor growth and lung metastasis of gastric cancer cells by inhibiting proliferation, enhancing autophagy and apoptosis in xenograft models. It was suggested that down-regulated BTG1 expression might promote gastric carcinogenesis partially due to its promoter methylation. BTG1 overexpression might reverse the aggressive phenotypes and be employed as a potential target for gene therapy of gastric cancer.

ING5 suppresses proliferation, apoptosis, migration and invasion, and induces autophagy and differentiation of gastric cancer cells: a good marker for carcinogenesis and subsequent progression.

Here, we found that ING5 overexpression increased autophagy, differentiation, and decreased proliferation, apoptosis, migration, invasion and lamellipodia formation in gastric cancer cells, while ING5 knockdown had the opposite effects. In SGC-7901 transfectants, ING5 overexpression caused G1 arrest, which was positively associated with 14-3-3 overexpression, Cdk4 and c-jun hypoexpression. The induction of Bax hypoexpression, Bcl-2, survivin, 14-3-3, PI3K, p-Akt and p70S6K overexpression by ING5 decreased apoptosis in SGC-7901 cells. The hypoexpression of MMP-9, MAP1B and flotillin 2 contributed to the inhibitory effects of ING5 on migration and invasion of SGC-7901 cells. ING5 overexpression might activate both ß-catenin and NF-κB pathways in SGC-7901 cells, and promote the expression of down-stream genes (c-myc, VEGF, Cyclin D1, survivin, and interleukins). Compared with the control, ING5 transfectants displayed drug resistance to triciribine, paclitaxel, cisplatin, SAHA, MG132 and parthenolide, which was positively related to their apoptotic induction and the overexpression of chemoresistance-related genes (MDR1, GRP78, GRP94, IRE, CD147, FBXW7, TOP1, TOP2, MLH1, MRP1, BRCP1 and GST-π). ING5 expression was higher in gastric cancer than matched mucosa. It was inversely associated with tumor size, dedifferentiation, lymph node metastasis and clinicopathological staging of cancer. ING5 overexpression suppressed growth, blood supply and lung metastasis of SGC-7901 cells by inhibiting proliferation, enhancing autophagy and apoptosis in xenograft models. It was suggested that ING5 expression might be employed as a good marker for gastric carcinogenesis and subsequent progression by inhibiting proliferation, growth, migration, invasion and metastasis. ING5 might induce apoptotic and chemotherapeutic resistances of gastric cancer cells by activating ß-catenin, NF-κB and Akt pathways.

The roles of BTG3 expression in gastric cancer: a potential marker for carcinogenesis and a target molecule for gene therapy.

BTG (B-cell translocation gene) can inhibit cell proliferation, metastasis and angiogenesis, cell cycle progression, and induce differentiation in various cells. Here, we found that BTG3 overexpression inhibited proliferation, induced S/G2 arrest, differentiation, autophagy, apoptosis, suppressed migration and invasion in MKN28 and MGC803 cells (p < 0.05). BTG3 transfectants showed a higher mRNA expression of p27, Bax, 14-3-3, Caspase-3, Caspase-9, Beclin 1, NF-κB, IL-1, -2, -4, -10 and -17, but a lower mRNA expression of p21, MMP-9 and VEGF than the control and mock (p < 0.05). At protein level, BTG3 overexpression increased the expression of CDK4, AIF, LC-3B, Beclin 1 and p38 (p < 0.05), but decreased the expression of p21 and ß-catenin in both transfectants (p < 0.05). After treated with cisplatin, MG132, paclitaxel and SAHA, both BTG3 transfectants showed lower viability and higher apoptosis than the control in both time- and dose-dependent manners (p < 0.05). BTG3 expression was restored after 5-aza-2'-deoxycytidine or MG132 treatment in gastric cancer cells. BTG3 expression was decreased in gastric cancer in comparison to the adjacent mucosa (p < 0.05), and positively correlated with venous invasion and dedifferentiation of cancer (p < 0.05). It was suggested that BTG3 expression might contribute to gastric carcinogenesis. BTG3 overexpression might reverse the aggressive phenotypes and be employed as a potential target for gene therapy of gastric cancer.

The cell surface GRP78 facilitates the invasion of hepatocellular carcinoma cells.

Invasion is a major characteristic of hepatocellular carcinoma and one of the main causes of refractory to treatment. We have previously reported that GRP78 promotes the invasion of hepatocellular carcinoma although the mechanism underlying this change remains uncertain. In this paper, we explored the role of the cell surface GRP78 in the regulation of cancer cell invasion in hepatocellular carcinoma cells. We found that neutralization of the endogenous cell surface GRP78 with the anti-GRP78 antibody inhibited the adhesion and invasion in hepatocellular carcinoma cell lines Mahlavu and SMMC7721. However, forced expression of the cell surface GRP78 facilitated the adhesion and invasion in SMMC7721. We further demonstrated that inhibition of the endogenous cell surface GRP78 specifically inhibited the secretion and activity of MMP-2 but did not affect the secretion and activity of MMP-9. We also found that inhibition of the cell surface GRP78 increased E-Cadherin expression and decreased N-Cadherin level. On the contrary, forced expression of the cell surface GRP78 increased N-Cadherin expression and decreased E-Cadherin level, suggesting that the cell surface GRP78 plays critical role in the regulation of EMT process. These findings suggest that the cell surface GRP78 plays a stimulatory role in the invasion process and may be a potential anti-invasion target for the treatment of hepatocellular carcinoma.

[Prokaryotic expression, purification and antigenicity identification of human GRP78 protein].

AIM: To construct a recombinant plasmid pGEX-4T-1-GRP78, express it and purify human glucose regulated protein 78 (GRP78). METHODS: GRP78 gene was amplified by PCR from the recombinant vector constructed in our laboratory. The PCR product was inserted into pGEX-4T-1 prokaryotic expression vector to generate pGEX-4T-1-GRP78. The pGEX-4T-1-GRP78 was then transformed into BL21 and GRP78 was expressed on induction of IPTG. After purification, GRP78 was released by thrombin cleavage, and its antigenicity was identified by ELISA. RESULTS: The GRP78 prokaryotic expression vector was successfully constructed as confirmed by enzyme digestion and DNA sequencing. ELISA demonstrated the antigenicity of the purified GRP78 protein. CONCLUSION: The recombinant prokaryotic expression vector pGEX-4T-1-GRP78 has been constructed successfully. The purified GRP78 has been obtained with good antigenicity, which will be used for GRP78-based serum diagnosis of hepatocellular carcinoma.

delta-Opioid receptor stimulation enhances the growth of neonatal rat ventricular myocytes via the extracellular signal-regulated kinase pathway.

1. The aims of the present study were to determine whether delta-opioid receptor stimulation enhanced proliferation of and to investigate the role of the extracellular signal-regulated kinase (ERK) pathway in ventricular myocytes from neonatal rats. 2. At concentratins ranging from 10 nmol/L to 10 micromol/L, [D-Ala2,D-Leu5]enkephalin (DADLE) concentration-dependently promoted myocardial growth and DNA synthesis and altered the cytoskeleton. 3. At 1 micromol/L, DADLE also increased the expression and phosphorylation of ERK. 4. These effects of 1 micromol/L DADLE were abolished by 10 micromol/L naltrindole, a selective delta-opioid receptor antagonist, 10 nmol/L U0126, a selective ERK antagonist, 1 micromol/L staurosporine, an inhibitor of protein kinase (PK) C, and 100 micromol/L Rp-adenosine 3',5'-cyclic monophosphorothioate triethylammonium salt hydrate (Rp-cAMPS), an inhibitor of PKA. 5. In conclusion, delta-opioid receptor stimulation enhances the proliferation and development of the ventricular myocytes of neonatal rats. The ERK pathway and related signalling mechanisms, namely PKC and PKA, are involved.