Effect of grape seed proanthocyanidin on cisplatin-induced nephrotoxicity in mice

AIM:To study the protective effect of grape seed proanthocyanidin (GSP) on nephrotoxicity induced by cisplatin (CP) in mice. METHODS:Male C57 mice were randomly divided into 4 groups: control group (N group, n=10), CP group (intraperitoneal injection of CP at dose of 20 mg/kg, n=20), GSP group (intragastric administration of GSP at dose of 500 mg/kg, n=15) and CP+GSP group (intragastric administration of GSP 30 min prior to intraperitoneal injection of CP and intragastric administration of the same dose of GSP 72 h later, n=20). On the 5th day after CP treatment, blood and kidney samples were collected. The renal pathological changes were examined by HE staining. The protein expression of glucose-regulated protein 78 (GRP78) and phosphorylated extracellular signal-regulated kinase (p-ERK) was examined by Western blotting and immunohistochemical staining. RESULTS:Renal index, blood urea nitrogen and serum creatinine were significantly higher in CP group than those in N group. The renal tissues were heavily damaged in CP group. The protein expression of GRP78 and p-ERK increased in CP group compared with N group. GSP treatment alleviated the increase in the renal index, blood urea nitrogen and serum creatinine. The damages of the renal tissues were attenuated. The protein expression of GRP78 and p-ERK was obviously reduced in CP+GSP group compared with CP group. CONCLUSION:GSP prevents kidney from CP-induced damage by suppression of endoplasmic reticulum stress.     

Reversing effect of naringin on cisplatin resistance in human lung cancer A549/DDP cells

AIM: To investigate the effect of naringin (NRG) on cisplatin (DDP) resistance in human lung cancer A549/DDP cells and its possible mechanism. METHODS: A549/DDP cells were cultured in vitro and treated with NRG and/or DDP at different concentrations for 24 h, and then the cell viability were measured by CCK-8 assay. The combination index (CI) of NRG and DDP were analyzed by Chou-Talalay method. The apoptosis rate was analyzed by flow cytometry. Western blot was performed to detect the protein levels of P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1), p-Akt, CXC chemokine receptor 4 (CXCR4), cleaved caspase-3, Bcl-2 and Bax.RESULTS: The protein levels of P-gp, MRP1, p-Akt and CXCR4 in the A549/DDP cells were higher than those in the A549 cells (P<0.05). The cell viability was remarkably reduced in a dose-dependent manner when A549/DDP cells were exposed to NRG and/or DDP (P<0.05), and the IC₅₀ values of NRG and DDP were 36.92 μmol/L and 129.77 μmol/L, respectively. When the inhibition rate exceeded 15%, NRG in combination with DDP produced a synergistic effect (CI<1). Combination treatment with NRG and DDP significantly induced apoptosis (P<0.05), up-regulated the protein levels of cleaved caspase-3 and Bax, and down-regulated the protein level of Bcl-2 (P<0.05). Meanwhile, NRG remarkably down-regulated the protein levels of P-gp, MRP1, p-Akt and CXCR4 in a dose-dependent manner (P<0.05). CONCLUSION: NRG may enhance the sensibility of A549/DDP cells to DDP most likely via up-regulating the protein level of Bax and down-regulating the protein levels of Bcl-2, P-gp, MRP1, p-Akt and CXCR4.     

DIM enhances effect of cis-diamminedichloroplatinum on growth inhibition and apoptosis in human prostate cancer cell PC-3

AIM: To study the effects of the combination of cis-diamminedichloroplatinum(DDP) and 3, 3-diindolylmethane (DIM) on the growth and apoptosis of human prostate cancer cell PC-3. METHODS: MTT method was applied to detect the cell growth inhibitory rate. The cell apoptosis was measured by the flow cytometry and acridine orange staining method. The expression of the anti-oncogene p21 was detected by RT-PCR technique. RESULTS: The combination of 60 μmol·L^-1 DIM and 0.4 mg·L^-1 DDP effectively inhibited the growth and induced apoptosis in PC-3 cells. This result was the same as the effect of using 4 mg·L^-1 DDP only. The cell growth inhibitory and apoptosis rates for the combination of DIM and DDP were much higher than those for the individual effect. Both the combination and the single effect of these two medicines (i.e., DIM and DDP) all strengthen p21 mRNA expression significantly, and the effect of combination was more significant. CONCLUSION: DIM significantly enhances the effects of DDP on the growth inhibition and apoptosis induction in PC-3 cells.     

Combination of dihydromyricetin and cisplatin significantly induces overexpression of Noxa and Bim in PC3 cells

AIM:To investigate the adjuvant effect of dihydromyricetin on cisplatin-based chemotherapy in prostate cancer and its mechanisms. METHODS:The viability of LNCaP and PC3 cells treated with different concentrations of dihydromyricetin and cisplatin was measured by MTT assay. The expression of FOXO1, Noxa and Bim, release of cytochrome C from mitochondria, and activation of caspase-9 and caspase-3 in PC3 cells treated with dihydromyricetin and cisplatin were determined by Western blot. Co-immunoprecipitation was performed to detect the interaction of apoptotic protease-activating factor-1 (Apaf-1) and caspase-9 in the PC3 cells. The apoptotic rate of PC3 cells was analyzed by flow cytometry. RESULTS:Adjuvant therapy of dihydromyricetin significantly enhanced the anti-tumor effect of cisplatin against prostate cancer in vitro. Dihydromyricetin significantly promoted the expression of FOXO1 in the PC3 cells. However, transfection with FOXO1 small interfering RNA (siRNA) obviously suppressed the adjuvant effect of dihydromyricetin. Combination of cisplatin and dihydromyricetin significantly induced the overexpression of Noxa and Bim, the release of cytochrome C, the interaction of Apaf-1 and caspase-9, the activation of caspase-9 and caspase-3, and the apoptosis in the PC3 cells. On the other hand, transfection with FOXO1 siRNA obviously suppressed the apoptotic pathway of PC3 cells treated with dihydromyricetin and cisplatin. CONCLUSION:Dihydromyricetin enhances the cytotoxicity of cisplatin against prostate cancer through the FOXO1-Bim/Noxa pathway in vitro.     

Protective effect of aqueous extract of velvet antler on cisplatin-induced nephrotoxicity in mice

AIM: To study the protective effect of aqueous extract of 2-branched and 3-branched velvet antler on cisplatin (CDDP)-induced nephrotoxicity in mice. METHODS:The mouse model of renal injury was induced by intragastric administration of CDDP at the dose of 15 mg/kg. After treatment, kidney index (KI), serum creatinine (SCr), blood urea nitrogen (BUN), the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the content of malondialdehyde (MDA) in the kidney were determined. The renal pathological changes were observed with HE staining. RESULTS: Aqueous extract of velvet antler at the tested dose markedly decreased BUN, SCr and the content of MDA, and elevated the activity of SOD and GSH-Px in the mice pretreated with CDDP (P<0.05). The pathological changes of the renal tissues were improved obviously, and the injury of the epithelial cells of renal tubules was mitigated. The effect of the aqueous extract of 2-branched velvet antler on renal function and cisplatin-induced nephrotoxicity was better than that of 3-branched one at the same concentration. CONCLUSION: The aqueous extract of 2-branched and 3-branched velvet antler has a certain protective effect on cisplatin-induced nephrotoxicity, which may be associated with increasing the anti-oxidative capability of mouse renal tissue.     

Cisplatin enhances proliferation-inhibitory and apoptosis-inducing effects of ECRG2 protein on human esophageal cancer EC9706 cells

Abstract: AIM: To investigate the effects of esophageal cancer-related gene 2 (ECRG2) protein combined with cisplatin (DDP) on the proliferation and apoptosis of human esophageal cancer EC9706 cells. METHODS: Methylthiazolyl tetrazolium (MTT) assay was used to examine the effects of single ECRG2 protein and ECRG2 protein combined with DDP on the proliferation of EC9706 cells. Hoechest 33258 staining was applied to analyze the effect of single ECRG2 protein and ECRG2 protein combined with DDP on apoptosis of EC9706 cells. The expression of p53 in EC9706 cells was detected by Western blotting. RESULTS: ECRG2 protein inhibited the proliferation of EC9706 cells. ECRG2 protein combined with DDP enhanced the inhibitory effect time- and dose-dependently in a certain range of concentrations. The number of apoptotic cells after treated with ECRG2 protein combined with DDP for 24 h was larger than those treated with single ECRG2 protein. The proliferation-inhibitory and qpoptosis-inducing expression of p53 was up-regulated in ECRG2 protein and DDP combination group compared with single ECRG2 protein group. CONCLUSION: DDP enhances the proliferation-inhibitory and apoptosis-inducing effects of ECRG2 protein on EC9706 cells. The apoptosis-inducing mechanism may be related to the up-regulation of p53 expression.     

Proliferation-inhibitory and apoptosis-inducing effects of cinnamic acid combined with cisplatin on human hepatocellular carcinoma cell line MHCC97

AIM：To investigate the effects of cinnamic acid (CA) combined with cisplatin on the proliferation and apoptosis of human hepatocellular carcinoma cell line MHCC97. METHODS：Human hepatocellular carcinoma cell line MHCC97 was culured and divided into CA group, cisplatin group, CA+cisplatin group and control group. MTT assay, inverted microscopy, annexin V-FITC/PI staining and flow cytometry were applied to identify the viability, morphology and apoptosis of the cells. The apoptosis-related signaling protein caspase-3 was detected by Western blotting. RESULTS：CA and cisplatin either alone or in combination significantly inhibited the proliferation and induced obvious apoptosis of MHCC97 cells, while CA alone or combined with cisplatin had no significant inhibitory effect on normal human liver L-02 cells. The rates of mid-and late apoptosis or necrosis were higher in cisplatin group than that in CA group or combination group, but the early apoptotic rate was just the opposite. Pro-apoptotic activity in combination group was much stronger than that in CA group or cisplatin group at lower concentration, and combination group promoted apoptosis and decreased the cytotoxic side effects of cisplatin. CA and cisplatin either alone or in combination also up-regulated the cleaved caspase-3 expression in a time-dependent manner, and the effects in CA group and combination group were higher than that in cisplatin group. CONCLUSION：CA and cisplatin either alone or in combination inhibit the growth of MHCC97 cells by inducing apoptosis, and the activation of caspase-3 may play important roles in these processes.     

Role of Fas overexperssion in reversing cisplatin resistance in stomach cancer cells

AIM: To study the effect of Fas on cisplatin resistance in stomach cancer cells and its possible mechanisms.METHODS: The expression of Fas at mRMA and protein levels in SGC-7901 cells and SGC-7901/DDP cells was determined by RT-qPCR and Western blot. Fas-containing adenovirus vector was transfected into the SGC-7901/DDP cells to upregulate Fas expression. The cell viability was detected by CCK-8 assay. The cell cycle and cell apoptosis were analyzed by flow cytometry. The protein levels of Fas, P38/p-P38, JNK/p-JNK, cleaved caspase-8/caspase-8 and cleaved caspase-3/caspase-3 were detected by Western blot.RESULTS: The expression of Fas at both mRNA and protein levels was significantly downregulated in the SGC-7901/DDP cells. Fas expression was decreased by cisplatin in a dose-dependent manner in the SGC-7901 cells. Overexpression of Fas suppressed the viability and induced apoptosis in the SGC-7901/DDP cells, and upregulated the protein levels of p-P38, p-JNK, cleaved caspase-8 and cleaved caspase-3.CONCLUSION: Overexpression of Fas increases the sensitivity of the SGC-7901/DDP cells to cisplatin, and inhibits the cell growth and promotes cell apoptosis. The mechanism may be related to the activation of JNK and P38 pathway.     

Antitumor effect of allicin on esophageal cancer EC109 cells compared with chemotherapeutics in vitro

AIM: To investigate the inhibitory effect of allicin on human esophageal cancer cell line EC109 and its possible mechanism by comparison with chemotherapeutic drugs. METHODS: The EC109 cells were treated with different concentrations of allicin, 5-fluorouracil and cisplatin. The cell viability was detected by CCK8 assay and the activity of lactic dehydrogenase (LDH) was analyzed at 6 h, 12 h, 24 h, 48 h and 72 h. The apoptosis of the EC109 cells induced by Z-VAD-FMK, allicin, allicin+Z-VAD-FMK, 5-fluorouracil and cisplatin was analyzed by flow cytometry with Annexin V-FITC and PI double staining. The enzyme activity changes of caspase-3, caspase-8 and caspase-9 were detected by spectrophotometry. RESULTS: Allicin had inhibitory effect on the growth of the EC109 cells and killed them in concentration-dependent and time-dependent manners. LDH activity was decreased compared with 5-fluorouracil and cisplatin. The increased activity of caspase-3 and caspase-8 in allicin-treated cells was statistically significant, but caspase-9 activity changed without statistical significance. CONCLUSION: Allicin inhibits the growth of EC109 cells in concentration-and time-dependent manners through extrinsic apoptosis pathways activated by caspase-8, and the side effects are weaker compared with 5-fluorouracil and cisplatin.