The anticancer activity of genistein on implanted tumor of human primary gastric carcinoma cells in nude mice

AIM: To investigate the apoptosis of implanted tumor of primary human gastric cancer cells in nude mice induced by genistein and the relation between this apoptosis and expression of bcl-2 and bax.METHODS: Establishing a transplanted tumor model by injecting human primary gastric cancer cells into subcutaneous tissue of nude mice.The different doses of genistein (0.5mg/kg,1mg/kg and 1.5 mg/kg ) were directly injected beside tumor body respectively,for six times at an interval of two days.Then changes of tumor volume were measured continuously and tumor inhibition rate of each group was calculated.We observed the morphologic alteration by electron microscope,measured the apoptotic rate by TUNEL staining method,detected the expression of apoptosis-regulated gene bcl-2 and bax by immunohistochemical staining and RT-PCR.RESULTS: Genistein could significantly inhibit carcinoma growth when it was injected near the carcinoma.Genistein induced implanted tumors cells to undergo apoptosis with apoptotic characteristics by transmission electron microscope.The apoptosis index of above three groups was increased progressively.Positive rate of Bcl-2 protein of above three groups was decreased progressively and positive rate of Bax protein of above three groups was increased progressively by immunohistochemical staining.The density of bcl-2 mRNA decreased progressively and the density of bax mRNA increased progressively with elongation of time by RT-PCR.CONCLUSION: Genistein is able to induce the apoptosis of transplanted tumor cells.This apoptosis may be mediated by down-regulating bcl-2 and up-regulating bax mRNA and its protein.     

Resveratrol induces apoptosis in human primary gastric carcinoma cells

AIM: To investigate the apoptosis in primary gastric cancer cells induced by resveratrol, and the relation between this apoptosis and expression of bcl-2 and bax. METHODS: In in vitro experiments, MTT assay was used to determine the cell growth inhibitory rate. Transmission electron microscopy and TUNEL staining were used to quantitatively and qualitively detect the apoptosis of primary gastric cancer cells before and after the resveratrol treatment. Immunohistochemical staining and RT-PCR was used to detect the expression of apoptosis-regulated gene bcl-2 and bax. RESULTS: Resveratrol inhibited the growth of primary gastric cancer cells in a dose- and time-dependent manner. Resveratrol induced primary gastric cancer cells to undergo apoptosis with typically apoptotic characteristics. TUNEL assay showed that after the treatment of primary gastric cancer cells with resveratrol for 24, 48, 72, 96 hours, the apoptotic indexs were 4.93%±0.19%, 16.74%±0.43%, 27.88%±0.36%, 36.84%±1.07% respectively. Immunohistochemical staining showed that after the treatment of primary gastric cancer cells with resveratrol for 24, 48, 72, 96 hours, the positive rates of Bcl-2 proteins were 20.68%±0.49%, 10.84%±0.33%, 6.80%±0.34%, 3.91%±0.15% and the positive rates of Bax proteins were 19.79%±0.98%, 30.74%±0.85%, 40.14%±1.17%, 60.08%±1.64%. After exposed to resveratrol for 24 h, 48 h, 72 h and 96 h, the density of bcl-2 mRNA decreased progressively with elongation of time and the density of bax mRNA increased progressively with elongation of time by RT-PCR. CONCLUSION: Resveratrol is able to induce the apoptosis in primary gastric cancer. This apoptosis may be mediated by down-regulation of Bcl-2 and up-regulation of Bax.     

Inhibitory effect of survivin-siRNA on prostatic subcutaneous xenografts in nude mice

AIM: To investigate the inhibitory effect of survivin-siRNA recombinant plasmid on prostate cancer xenografts. METHODS: Prostatic cancer DU145 cells were cultured and subcutaneously injected into nude mice. When the tumor grew to 8 mm in diameter, it was aseptically removed and divided into about 2 mm blocks through surgery and subcutaneously implanted into another nude mice. After the prostatic cancer xenograft model was reconstructed, the mice were treated with survivin-siRNA plasmid and control scrambled siRNA plasmid using electric transfection method. The tumor growth curve was plotted and the inhibitory rate was calculated. HE staining, immunohistochemical staining and TUNEL assay were applied to observe the effect of survivin-siRNA on the xenografts. RESULTS: The prostatic cancer xenograft model was successfully constructed in vivo. Compared with mock and scrambled siRNA groups, transfection of survivin-siRNA recombinant plasmid obviously inhibited the tumor growth with the inhibitory rates of 61.81% and 62.87%, respectively. Compared with both controls, survivin-siRNA depressed the protein expression of survivin and promoted the cell apoptosis. CONCLUSION: Survivin-siRNA recombinant plasmid significantly inhibits the growth of prostatic tumor xenografts by inhibiting the protein expression of endogenous survivin and promoting cell apoptosis.     

Effect of captopril on AGS nude mouse model of gastric cancer

AIM: To observe the effect of captopril on the genesis and development of gastric cancer, and to explore its clinical treatment feasibility for gastric cancer. METHODS: The human gastric cancer cell line AGS was used to establish a tumor model in nude mice, and the model mice were randomly divided into 3 groups: positive control (5-fluorouracil) group, normal control (saline) group and experimental (captopril) group. After intraperitoneal injection or intragastric administration of the drugs, the tumor growth curve was determined, and the tumor tissues were also sampled to detect the expression of Ki-67, STAT3, Bax and Bcl-2 by real-time quantitative PCR and immunohistochemistry. The apoptosis was detected by TUNEL+DAPI staining. RESULTS: The tumor growth curve showed that the tumor model in the nude mice was successfully established. The tumor volumes among groups showed significantly different after 14 d growth. The increase in the tumor volume in normal control group was significantly faster than that in the other two groups, and that in positive control group was the slowest. The expression of Bax in captopril group increased, and the expression of STAT3, Ki-67 and Bcl-2 was reduced as compared with normal control group and positive control group. Compared with normal control group, the apoptotic rate increased significantly, and the protein expression of p-STAT3 and STAT3 decreased obviously in positive control group and captopril group. CONCLUSION: With better feasibility, angiotensin-converting enzyme inhibitor captopril has a significant effect on treating gastric cancer in the AGS nude mouse model by regulating the expression of STAT3, Bax, Bcl-2 and Ki-67 to accelerate the apoptosis of cancer cells, thus inhibiting tumor growth.     

Changes of bcl-2, bax expression and neuron apoptosis in lymphostatic encephalopathy of rats

AIM: To investigate the changes of bcl-2, bax expression and neuron apoptosis of cerebral cortex in lymphostatic encephalopathy of rats. METHODS: The model of lymphostatic encephalopathy was established by occluding and removing both the shallow and deep cervical lymph nodes in rats. The animals were sacrificed at 1, 2, 3, 5, 7 and 14 days after operation. HE staining was used to observe the structure of brain tissues and TUNEL staining was used to detect in situ cell apoptosis. The expressions of bcl-2 and bax were examined by RT-PCR. RESULTS: Cerebroedema appeared at the second day and was the most serious at the 5th day after blockage of cervical lymphatics. The number of TUNEL positive cells and the expression of bax began to increase at the 2nd day, reached a peak at the 5th day and dropped to control level at the 14th day. The expression of bcl-2 began to increase at the 1st day, reached a peak at the 5th day and dropped to control level at the 7th day. The increasing extent of bax was higher than that of bcl-2. CONCLUSION: The blockage of cervical lymphatics can lead to lymphostatic encephalopathy. Apoptosis is the main form of neuron death in the cortex and has relation to the increasing expression of bcl-2 and bax.     

Therapeutic effect of 3TSR on gastric carcinoma in nude mice

AIM: To investigate the anti-tumor efficacy of angiogenic inhibitor three hrombospondin-1 type repeats (3TSR) on gastric cancer. METHODS: Human gastric carcinoma cell line SGC-7901 was inoculated subcutaneously to BALB/c mice, and then the mice were divided into two groups (8 mice each): control group and 3TSR group. After administration of 3TSR by intraperitoneal injection for 3 weeks, mice were sacrificed. The tumor volume and percentage of necrotic area were detected. The micro-vessel index and cell proliferation index were detected by immunohistochemistry method. The apoptosis rate of gastric carcinoma cells was measured by TUNEL method. The vascular endothelial cell apoptosis rates were detected by CD31/TUNEL/DAPI staining. RESULTS: The tumor volume in 3TSR group was (648.34±126.91)mm3, significantly lower than that in control group (P<0.05). The percentage of tumor necrosis area in 3TSR group was (39.6±7.8)%, almost increased by 69.2% than that in the control. Average micro-vessel numbers and micro-vessel area in 3TSR were 12.8±4.1 and (689.3±118.6) μm2, respectively, significantly lower than those in the control. The proliferation index and apoptosis rate in 3TSR group were (40.0±7.1)% and (3.4±1.2)%, respectively. No difference between 3TSR group and the control was observed. The endothelial cell apoptosis rate in 3TSR group was (11.6±2.8)%, significantly higher than that in control group (2.9±1.5)%. CONCLUSION: 3TSR inhibits tumor angiogenesis, remarkably reduces tumor volume, average micro-vessel and increased tumor necrosis. 3TSR shows no direct inhibitory effects on gastric cancer cells. The antiangiogenesis effects of 3TSR on gastric carcinoma may be due to the induction of apoptosis of vascular endothelia cells.     

Inhibitory effect of survivin antisense oligodeoxyribonucleotide combined with DDP in nude mice bearing human osteosarcoma xenograft

AIM:To investigate the feasibility and its mechanisms of improving therapeutic effect by antisense gene therapy combined with chemotherapy in osteosarcoma. METHODS:The human osteosarcoma implanted tumor model in the nude mice was established. By intratumoral injection and abdominal cavity administration, the tumor bearing mice were treated with survivin ASODN in combination with diamminedichloroplatinum (DDP) for a week. Comparison with each single-agent therapy and control group was performed in aspects such as tumor growth condition, pathological changes of tumor tissues;survivin protein expression in tumor tissues by immunohistochemistry, survivin mRNA expression levels by RT-PCR method and tumor apoptosis by Tdt-mediated dUTP nick end labeling (TUNEL). RESULTS:All nude mice survived the therapy. As compared with the control group, the antisense gene therapy group presented synchronous decrease in survivin mRNA and protein expression;all therapy group displayed tumor growth inhibition and cell apoptosis with different extent;while in contrast to single-agent therapy group, the combined therapy group showed stronger inhibition of tumor growth and abundant tumor cell apoptosis with the highest apoptotic rate. CONCLUSION:Synergistic effect was achieved by combination of DDP with ASODN that may overcome drug resistant of DDP and the combined strategy may shed new light on the cancer therapy.     

Growth-inhibitory effects of selective cyclooxygenase-2 inhibitor on colon cancer cells and its possible mechanisms

AIM: To evaluate the growth-inhibitory effects of NS-398, a selective cyclooxygenase-2 inhibitor, in human colon cancer HT-29 cells and its possible mechanisms. METHODS: MTT assay was applied to detect the cell proliferation. Flow cytometry was performed to detect apoptosis rate and cell cycle. RT-PCR was used to detect the expression of bcl-2 mRNA and bax mRNA. Alteration of cytoskeleton component F-actin was observed by confocal laser scanning microscope. RESULTS: NS-398 could inhibit growth of HT-29 cells in dose-and time-dependent manners. Flow cytometry revealed that NS-398 could induce apoptosis and cause G0/G1 arrest of HT-29 cells in a dose-dependent manner. After 72 h incubation with NS-398 at different concentrations, the expression level of bcl-2 mRNA was lowered and the ratio of bcl-2 to bax was decreased in HT-29 cells. F-actin was mainly distributed around nuclei forming annular structure in HT-29 cells. After exposure to NS-398, the annular structure around nuclei disappeared and fluorescence intensity of F-actin decreased obviously. CONCLUSION: NS-398 can inhibit the growth effectively and induce apoptosis in HT-29 cells in vitro, which is associated with the down-regulation of bcl-2 to bax ratio and the disruption of cytoskeleton.     

Attenuated Salmonella carrying pGRIM-19-si-survivin co-expression plasmid inhibits growth of prostate cancer subcutaneous xenografts in vivo

AIM：To explore the effects of pGRIM-19-si-survivin co-expression plasmid carried by human attenuated Salmonella on prostate cancer subcutaneous xenograft growth in nude mice. METHODS：Prostate cancer xenograft model was established in nude mice. Co-expression plasmids carried by attenuated Salmonella were introduced by intraperitoneal injection. The xenograft volumes were monitored timely. Immunohistochemical staining, RT-PCR and TUNEL assay were applied to investigate the related mechanisms that pGRIM-19-si-survivin inhibited tumor growth in vivo. RESULTS：Compared with psi-survivin and pGRIM-19 carried by attenuated Salmonella (control groups), the tumor volumes were reduced markedly in pGRIM-19-si-survivin plasmid group. The mean shrinkage rates were 2.36 and 3.02 times. pGRIM-19-si-survivin co-expression plasmid carried by attenuated Salmonella inhibited survivin expression but strengthened GRIM-19 expression obviously (P<0.05). The mRNA expression of apoptosis-related proteins such as Bcl-xL, Stat3, cyclin D1 and c-Myc was inhibited, and the vascular endothelial growth factor (VEGF) mRNA and Ki67 protein were also inhibited, but the caspase-3 mRNA expression was up-regulated (P<0.05) with significant cell apoptosis. CONCLUSION： pGRIM-19-si-survivin co-expression plasmid carried by human attenuated Salmonella inhibits the growth of prostate cancer subcutaneous xenografts in nude mice by promoting cell apoptosis and inhibiting prostatic cancer proliferation.     

Inhibitory effect of liposomes survivin antisense oligonucleotide on human hepatic carcinoma transplanted subcutaneously in nude mice

AIM: To explore the effects of liposomes survivin antisense oligonucleotides (ASODN) on growth of human hepatic carcinoma transplanted subcutaneously in nude mice. METHODS: Nude mouse model of human hepatic cancer was established by transplantation of hepatic cancer cell line SMMC-7721/ADM subcutaneously. Models were divided randomly into six groups: control group, liposome group, sense oligonucleotide (SODN) group, 200 μg/L, 400 μg/L and 600 μg/L ASODN groups. Different treatments were given respectively. Weight and volume of subcutaneous tumors were measured, and tumor growth inhibitory rate was calculated. Morphological changes of transplanted tumor cells were observed under light microscope. The expression of Survivin was detected by immunohistochemistry. RESULTS: The growth of tumors was significantly inhibits in all ASODN groups compared with control, liposome and SODN groups (P<0.05). Volume of subcutaneous tumors decreased in a time-dependent and dosage-dependent manner (P<0.5). CONCLUSION: Survivin ASODN inhibits the growth of human hepatic carcinoma in nude mice.     

Effects of tetrahydroxystilbene-2-O-β-D-glucoside on apoptosis and expression of bcl-2/bax/caspase-3 in HUVECs treated with homocysteine

AIM：To explore the effects of tetrahydroxystilbene-2-O-β-D-glucoside (TSG) from Polygonum multiflorum on the apoptosis and the mRNA expression of bcl-2, bax and caspase-3 in human umbilical vein endothelial cells (HUVECs) treated with homocysteine (Hcy). METHODS：Cultured HUVECs were treated with Hcy (3 mmol/L) to establish a Hcy-damaged model. HUVECs in TSG treated groups were pre-incubated with TSG at concentrations of 1 μmol/L and 10 μmol/L for 2 h before treated with Hcy. Cell nuclear damage was detected by Hoechst 33342 staining. Cell apoptosis was determined by flow cytometry. The mRNA expression of bcl-2, bax and caspase-3 was measured by real-time fluorescence quantitative RT-PCR. RESULTS： After treatment with Hcy at concentration of 3 mmol/L, the nuclear damage and apoptotic rate of HUVECs were higher than that in normal group. The expression of bcl-2 was lower, and the expression of Bax and caspase-3 was higher than that in normal group. On the other hand, pre-incubation with TSG at concentrations of 1 μmol/L and 10 μmol/L decreased the nuclear damage and cell apoptosis, increased the expression of bcl-2, and decreased the expression of bax and caspase-3 as compared with the cells only treated with Hcy. CONCLUSION：TSG reduces the apoptosis of HUVECs induced by Hcy, and the mechanism might be associated with regulating the expression of bcl-2, bax and caspase-3.     

Effects of RNA interference of FABP5 on subcutaneous tumor of human hepatocellular carcinoma cell line HepG 2 transplanted in nude mice

AIM: To investigate the effect of recombinant lentiviral vector for RNA interference (RNAi) on the expression of fatty acid-binding protein 5 (FABP5) gene in hepatocellular carcinoma HepG2 cells and tumor formation in nude mice.METHODS: RNAi lentiviral vector was used in the experiment. Human hepatocellular carcinoma HepG2 cells were divided into 3 groups:the HepG2 cells in experimental group were transfected with the recombinant lentivirirus vector LV-shRNA-FABP5, the cells in negative control group were transfected with a control lentiviral vector LV-shRNA-NC, and the cells in normal control group were without any treatment. The nude mice were randomly divided into 3 groups. The growth of the transplanted tumor cells in the nude mice was observed. The tumor growth curve, volume and weight were determined 4 weeks after the cell inoculation. The expression of FABP5 was detected by real-time PCR, Western blot and immunohistochemical staining.RESULTS: Transfection of the lentiviral vector FABP5-shRNA obviously reduced FABP5 expression in the HepG2 cells. Tumor formation was all positive in the 3 groups of the nude mice inoculated with the tumor cells. Compared with normal control group and negative control group, the tumor growth slowed significantly in experimental group with smaller volume and weight. FABP5 expression in the transplanted tumor tissues was significantly down-regulated at mRNA and protein levels in experimental group as compared with normal control group and negative control group.CONCLUSION: RNAi-induced down-regulation of FABP5 effectively inhibits the growth of transplanted hepatocellular carcinoma, suggesting that FABP5 gene may be an effective target for gene therapy in treating liver cancer.     

NFATc1 promotes vascular generation of epithelial ovarian cancer transplanted tumor by regulating CXCR2, FGF-2 and PDGF-BB

AIM: To investigate the role of NFATc1 in vascular generation in the nude mice transplanted with human ovarian cancer SKOV3 cells. METHODS: NFATc1 expression was silenced by siRNA in SKOV3 cells. Human ovarian cancer transplantation nude mouse model was established by transplanting with SKOV3 cells in which the NFATc1 gene was silenced by siRNA technique. The expression of NFATc1, CXCR2, FGF-2 and PDGF-BB at mRNA and protein levels was determined by RT-PCR, Western blotting and immunohistochemical staining. The tumor growth, angiogenesis and lymphangiogenesis were also observed. RESULTS: Over-expression of NFATc1 was observed in human ovarian cancer tissues. The silencing of NFATc1 expression by siRNA decreased tumorigenesis of transplanted ovarian cancer cells in the nude mice, reduced tumor vascular generation and inhibited the expression of CXCR2, FGF-2 and PDGF-BB at mRNA and protein levels. CONCLUSION: NFATc1 is overexpressed in ovarian cancer. NFATc1 silencing regulates the tumor vascular generation. NFATc1 thus has potential as a therapeutic target and for use in the diagnosis and evaluating prognosis of epithelial ovarian cancer.     

Inhibition of survivin expression in BGC-823 cells by RNA interference

AIM: To investigate the feasibility and specificity of gastric carcinoma gene therapy by utilizing RNA interference (RNAi) to inhibit survivin expression in vitro and in vivo. METHODS: Small interference RNA (siRNA) homologous to survivin was designed. pTZU6+1-siRNA-survivin vector was constructed and transfected into BGC-823 cells. The transplanted BGC-823 tumor in nude mice was established to induce RNAi. The changes of survivin gene expression, tumor cell cycle and cell apoptosis were detected by flow cytometry, RT-PCR, Western blotting, immunochemistry and TUNEL. RESULTS: The expression of survivin was obviously inhibited by RNAi in vitro. The phase of cell cycle indicated the reduction of S phase, while G1/G0 phase increased. Cell apoptosis was obvious. Both the mRNA level and the protein expression of survivin decreased obviously. The tumor size reduced after treated with pTZU6+1-siRNA-survivin vector in vivo. The expression of survivin decreased in siRNA treatment group. In contrast, little change in control group in vitro and in vivo was observed. CONCLUSION: RNA interference down-regulates survivin gene expression, inhibits BGC-823 cell proliferation and induces cell apoptosis with good specificity, which may be a possible new approach for neoplasm gene therapy.     

Inhibition of 17-DMAG on VEGF expression in transplanted human gastric cancer in nude mice

AIM: To observe the anti-tumor effects of heat shock protein 90(HSP90) inhibitor 17-dimethylaminoethylamino-17 demethoxygeldanamycin (17-DMAG) on the tumor growth and angiogenesis in implanted gastric cancer nude mouse model. METHODS: Human gastric cancer cell HGC-27 was subcutaneous inoculation into the nude mice to develop a tumor model. Ten days later, 24 mice with implanted tumor were randomly divided into 3 groups: 17-DMAG group (receiving 17-DMAG at dose of 25 mg/kg), control group (treated with NS at dose of 10 mL/kg) and 5-fluorouracil(5-FU) group (treated with 5-FU at dose of 20 mg/kg). Four weeks after treatment, the tumor volume and weight, and the inhibitory rates of tumor growth were evaluated. In the meantime, the expression of CD31 was detected by immunohistochemical staining. The expression of vascular endothelial growth factor (VEGF) was determined by Western blotting. RESULTS: The size of xenografts in 17-DMAG treatment group was (288.10±23.32)mm³, and that in 5-FU treatment group was (366.37±26.42)mm³, both were significantly smaller than that in control group (957.66±117.51)mm³. The tumor weight in 17-DMAG treatment group was (0.41±0.02)g, significantly less than that in control group (1.12±0.08)g. The inhibitory rate of 17-DMAG was 63%. A significant decease of MVD in 17-DMAG group (21.72±1.24) was observed as compared to 5-FU group (36.70±1.51) and control group (37.78±1.68). The expression of VEGF in 17-DMAG group (15.39±4.37) was significantly lower than that in 5-FU group (26.11±6.26) and control group (36.45±7.45). CONCLUSION: HSP90 inhibitor 17-DMAG suppresses the expression of VEGF and the angiogenesis of the gastric cancer to inhibit the tumor growth.     

Effect of fucoidan on inhibition of proliferation and induction of apoptosis in human breast carcinoma cell line MCF-7

AIM: To investigate the effects and related mechanism of fucoidan on the proliferation and apoptosis in breast carcinoma cell line MCF-7. METHODS: MCF-7 cells were treated with different concentrations of fucoidan (100 mg/L, 300 mg/L, 500 mg/L, 1 000 mg/L) for 48 h. Cell viability was measured by MTT assay. Apoptosis morphological and biochemical changes were detected by Hoechst 33258 staining and agarose gel electrophoresis. The expression of 〖STBX〗bcl-2〖STBZ〗 and bax was examined by RT-PCR and Western blotting. RESULTS: Fucoidan at different concentrations (100 mg/L, 300 mg/L, 500 mg/L, 1 000 mg/L) effectively inhibited the proliferation of MCF-7 cells (P<0.01). The inhibitory ratio and apoptosis rate increased in a concentration-dependent manner. Agarose gel electrophoresis of DNA revealed the characteristic “ladder” pattern of apoptosis. Fucoidan down-regulated the expression of 〖STBX〗bcl-2〖STBZ〗 and up-regulated bax in the levels of mRNA and protein. The ratio of Bcl-2 to Bax decreased as the concentrations of fucoidan increased (P<0.05). CONCLUSION: Fucoidan inhibits the cell proliferation by inducing cell apoptosis, and the apoptosis is related to the down-regulation of anti-apoptotic protein Bcl-2 and up-regulation of apoptotic protein Bax.     

Effects of EBV infection on growth and apoptosis of nasopharyngeal carcinoma cell line

AIM:To explore the effect of EBV infection on growth and apoptosis of nasopharyngeal carcinoma(NPC)cell line.METHODS:NPC cell line CNE1 was directly infected by Epstein Barr virus(EBV).The expression of EBV-latent membrane protein 1(EBV-LMP1)and bcl-2 were detected by immunohistochemistry method(LSAB).The growth of NPC cells was identified by MTT method.Apoptotic carcinoma cells were detected by flowcytometry analysis and the terminal deoxynucletidyl transferase-medicated dUTP-biotin nick end labeling(TUNEL)methods.RESULTS:EBV-LMP1 was positive in CNE1 infected by EBV(E-CNE1).Compared with CEN1, the growth of E-CNE1 apparently increased(P<0.01).No apoptotic carcinoma cel s were detected and bcl-2 postive cells were 2%~3%respectively in 2 kinds of NPC cells.CONCLUSION:Growth of NPC cells is enhanced by EBV infect ion and EBV-LMP1 expression, but no influence on expression of bcl-2 and apoptosis of NPC cells.     

C-reactive protein induces apoptosis in human renal tubular epithelial cells

ATM: To explore whether the C-reactive protein (CRP) level in microinflammation state induces the apoptosis of renal tubular epithelial cells. METHODS: HK-2 cells were stimulated with recombinant human CRP. Annexin-FITC-PI staining and flow cytometry were used to detect the percentage of apoptotic cells. Morphology observation of apoptosis was assessed by Hoechst 33258 staining. Caspase-3 activity was measured by a colorimetric assay. The expression of apoptotic gene bax and anti-apoptotic gene bcl-2 at mRNA levels was determined by real-time PCR. RESULTS: CRP induced apoptosis of HK-2 cells in a time- and dose-dependent manner. The maximal apoptotic effect of CRP concentration was 10 mg/L CRP at concentration of 20 mg/L. CRP treatment was associated with the characteristic morphological features of apoptosis such as condensation, fragmentation or margination of nuclear chromatin. CRP exposure increased caspase-3 activity, up-regulated the mRNA expression of Bax and down-regulated the mRNA expression of Bcl-2. CONCLUSION: Slightly increased CRP level has the potential to induce apoptosis of renal tubular cells.