and laminin on adhesion and proliferation of human hepatocellular carcinoma cell

AIM:To explore the effects of PMA(phorbol-12-myristate-13-acetate, a tumor promoter, mimicking the action of diacylglycerol on PKC)and laminin on the adhesion and the proliferation of human hepatocellular carcinoma cells, and provide a new clue to liver cancer treatment.METHODS:Human hepatocellular carcinoma cell line(BEL-7402)was used to identify the endogenous laminin and protein kinase C-α(PKC-α) expression, and the effects of laminin and PMA on the adhesion and the proliferation were also investigatedin vitro.RESULTS:By the effect of exogenous laminin, human hepatocellular carcinoma cell (BEL-7402) possessed endogenous laminin expression and increased the adhesion and the proliferation, which was showed the synergistic action by the effect of PMA in combination. By the action of PMA alone, the proliferation and the PKC-α expression increased by exogenous laminin were decreased, and the adhesion and the endogenous laminin expression were increased.CONCLUSIONS:The finding suggested that the adhesion and the proliferation of human hepatocellular carcinoma cell were closely related to the effects of endogenous or exogenous laminin, which were associated with cPKC-α activity. Therefore, the application of anti-laminin antibody in combination with PKC antagonist might be a new clue to find out the therapy for liver cancer.     

Differentiation induction of human hepatocellular carcinoma BEL-7402 cells with tissue extracts of injured liver

AIM: To observe the effects of tissue extracts of injured liver on BEL-7402 cells,and explore a novel strategy of tumor therapy by differentiation induction. METHODS: Differentiation induction of human hepatocellular carcinoma cell line BEL-7402 was carried out with liver tissue extracts from an animal model of liver injury. The changes of cell biological characteristics, such as morphological features of the cells, MTT growth curves and cell cycle distribution, were dynamically observed. RESULTS: After exposed to the tissue extracts of injured liver, the number of mitotic cells was decreased, and the speed of growth and the proliferation of carcinoma cells were slowed down dramatically. The percentage of the cells in G₀/G₁ phase was increased, while the cells in S phase was decreased. The level of proliferation index (PI) also declined. CONCLUSION: The tissue extracts of injured liver affect the differentiation status of human hepatocellular carcinoma cell line BEL-7402, promote the cell differentiation and reduce the tumor characteristics. The tissue extracts of injured liver possess an important potential as a tumor differentiation inducer.     

Inhibition of human hepatocellular carcinoma cell proliferation by galactose receptor mediated c-myc antisense oligonucleotide

AIM: To evaluate the inhibitory effect of galactose (Gal)-polyethyleneimine (PEI)-c-myc antisense oligodeoxynucleotide (ASODN) complex on proliferation of human hepatocellular carcinoma cells. METHODS: Human hepatocellular carcinoma cell line Bel-7402 was treated with Gal-PEI-ASODN complex. Cell proliferation was tested by trypan blue dye at different time points and with various concentrations of ASODN treatment. Cell morphology was observed under inverted microscope, cell hypodiploid percentage was analyzed by flow cytometry and cell ultrastructure was observed through electron microscopy. RESULTS: Compared with ASODN group (20 μmol/L) from 0 h to 96 h, Gal-PEI-ASODN complex (with ASODN 0.75 μmol/L) significantly suppressed Bel-7402 cells proliferation, the ASODN concentration within Gal-PEI-ASODN complex and time course acquired were significantly lower and shorter, respectively. Incubated with pure ASODN at different concentrations for 72 hours, cell proliferation was inhibited and IC₅₀ was 20.9 μmol/L; while mediated with galactose receptor for 48 hours, ASODN significantly inhibited cell proliferation and IC₅₀ was only 0.294 μmol/L, the inhibitory efficacy of ASODN enhanced 70.9 folds. While Bel-7402 cells were incubated with Gal-PEI-ASODN complex for 48 hours, cell hypodiploid percentage was much higher than ASODN groups and cell apoptosis was seen under electron microscopy. CONCLUSIONS: Galactose receptor mediated ASODN delivery may significantly increase proliferation inhibition efficacy on Bel-7402 cells.     

Influence on killing effect of NK cells in vitro by up-regulation of HLA-E expression in hepatocellular carcinoma Bel7402 cells

AIM: To investigate the influence on the killing effect of NK cells in vitro by up-regulation of human leukocyte antigen-E (HLA-E) expression in hepatocellular carcinoma Bel7402 cells. METHODS: The recombinant lentiviral vector (Lentivirus/CMV/GFP-HLA-E) was constructed and transfected into hepatocellular carcinoma Bel7402 cells. The HLA-E gene expression at mRNA and protein level was monitored by the methods of real-time RT-PCR and Western blotting. The influence on the killing effect of NK cells in vitro by up-regulation of HLA-E expression in hepatocellular carcinoma Bel7402 cells and by HLA-ABC antibody blocking the site on the surface of target cells was analyzed.RESULTS: Real-time RT-PCR showed that there was a significant increase in HLA-E mRNA level in hepatocellular carcinoma Bel7402 cells transfected with Lentivirus/CMV/GFP-HLA-E at 24 h (P<0.05) and 48 h,72 h, 96 h (P<0.01) as compared to blank group. There was also a significant increase in exogenous/endogenous HLA-E proteins at 12 h, 24 h, 48 h, 72 h and 96 h by Western blotting (P<0.01). Without HLA-ABC antibody blocking, there was a statistical difference for the killing effect of NK cells,comparing Bel7402 Lenti HLA-E group with Bel7402 group (P<0.05). Comparing HLA-ABC antibody blocking group with no HLA-ABC antibody blocking group, a statistical difference for the killing effect of NK cells (P<0.05) was observed. There was also a statistical difference for the killing effect of NK cells between Bel7402 with blocking group and Bel7402 Lenti HLA-E with blocking group (P<0.05). CONCLUSION: The vector of Lentivirus/CMV/GFP-HLA-E has an active up-regulation effect in HLA-E mRNA level and HLA-E protein level. While up-regulation of HLA-E in target cells, the killing effect of NK cells on target cells is obviously weakened. Blockage of the sites on the surface of target cells by HLA-ABC antibody universally enhances the killing effect of NK cells on the target cells.     

Expression of human leukocyte antigen E in hepatocellular carcinoma cell lines

AIM: To investigate the human leukcyte antigen E (HLA-E) expression in hepatocellular carcinoma cell lines. METHODS: The techniques of real-time PCR and Western blotting were used to study the HLA-E expression in the 5 cell lines of hepatocellular carcinoma and a fetal liver cell line at mRNA and protein levels. RESULTS: The results of real-time PCR showed that no statistical difference of HLA-E mRNA level between fetal liver cell L02 and other 4 cell lines of hepatocellular carcinoma (HepG2, Bel7402, PLC and MHCC97) was observed, and almost absence of HLA-E mRNA expression in Hep3B2.1-7 cells was detected. However, the results of Western blotting showed that there was a significant statistical difference of HLA-E protein levels between L02 cells and the 5 cell lines of hepatocellular carcinoma (HepG2, Bel7402, PLC, MHCC97 and Hep3B2.1-7), and no HLA-E protein in Hep3B2.1-7 cells was detectable. CONCLUSION: Asynchronization of HLA-E expression between mRNA and protein levels was found in hepatocellular carcinoma cell lines.     

Activated NK cells against human hepatocellular carcinoma cell lines in vitro and in vivo

AIM: To evaluate the role of natural killer(NK) cells against a variety of human hepatocellular carcinoma (HCC) cell lines in vitro and in vivo, and to investigate the expression of MHC class I chain-related protein (MIC protein) in these HCC cell lines. METHODS: Peripheral blood mononuclear cells (PBMC) were isolated from 50 mL peripheral blood donored by a healthy volunteer and cultured in the NK cell kit followed by amplification and cytokine activation. The release of lactate dehydrogenase (LDH) was detected by lysis experiment. Animal experiments were performed following vaccination with HCC cell lines (BEL7402, HepG2 and SMMC7721) in BALB/c-nu/nu mice. The diameters of the tumors were measured and the growth curves of difference cell lines were delineated. Three weeks later, these mice were sacrificed and the weight of the transplanted tumors was also detected. Furthermore, the expression of MIC protein was determined. RESULTS: The obvious differences of lysis effects of NK cells on different cell lines were observed, in which the lysis effect of NK cells on K562 cells was the strongest, the effect on BEL7402 cells was in the middle and the effect on SMMC7721 cells was the weakest. In animal experiments, NK cells also showed obvious and different restraining effects on a variety of HCC cell line-transplanted tumors in nude mice. The tumor inhibitory rates of NK cells were 43.5% in BEL-7402 cell-transplanted tumor, 40.7% in HepG2 cell-transplanted tumor and 36.0% in SMMC-7721 cell-transplanted tumor. The protein expression of MIC was 48.7%, 32.8% and 0.9% in the 3 cell lines,respectively. CONCLUSION: The lysis effects of NK cells on a variety of human HCC cell lines are different. The expression of MIC in the tumor cells may play distinct role in evaluating these differences.     

Effect of Sonic Hedgehog signaling blockade on growth of hepatocarcinoma cells

AIM: To investigate the effect of Sonic Hedgehog (Shh) signaling blockade on the growth of hematocarcinoma cells and underlying mechanisms. METHODS: The expression of Shh signaling molecules in hematocarcinoma cell lines BEL-7402, Huh7 and HepG2 was detected by RT-PCR. The cell viability was detected by MTT assay. The cell cycle and apoptosis were analyzed by flow cytometry. The expression of apoptosis-related proteins was determined by Western blot. RESULTS: Shh signaling molecules were all expressed in BEL-7402, Huh7 and HepG2 cells. The mRNA expression of Patched (Ptch), Gli1 and Gli2 was down-regulated by anti-Shh antibody. Blockade of Shh signaling pathway inhibited the proliferation of hepatocarcinoma cells with increasing cells in G₀/G₁ phase and induced the apoptosis of hepatocarcinoma cells. Treatment with anti-Shh antibody down-regulated the protein expression of pro-caspase-3, pro-caspase-8 and pro-caspase-9, while up-regulated the protein levels of cleaved caspase-3, cleaved caspase-8 and cleaved caspase-9 in BEL-7402 cells. CONCLUSION: Blockade of Shh signaling pathway inhibits the growth of hepatocarcinoma at different levels by cell cycle arrest and inducing apoptosis of hematocarcinoma cells.     

Different inhibition of hepatocarcinoma cell growth by As2O3 in SMMC-7721 and BEL-7402 cell lines

AIM: To explore the different inhibitory effect of arsenic trioxide (As₂O₃) on hepatocarcinoma cell growth in SMMC-7721 and BEL-7402 cell lines and its mechanism. METHODS: The cell culture and trypan blue staining were used to study the inhibitory effect of arsenic trioxide on cell growth, and the glutathione (GSH) contents in hepatocarcinoma cells treated with arsenic trioxide were detected. RESULTS: Arsenic trioxide inhibited the growth of BEL-7402 cells in a time and dose-dependent manner. The inhibitory effect was significant at a lower dose of 0.50 μmol/L for 24 h, however, to SMMC-7721 cells, a higher dose of 2.00 μmol/L for 96 h was needed. The inhibitory rate of arsenic trioxide (0.25-2.00 μmol/L) on BEL-7402 cell growth was higher than that on SMMC-7721 cells. The content of GSH in SMMC-7721 cells was much higher than that in BEL-7402 cells . CONCLUSION: There was a significant difference in inhibition of hepatocarcinoma cell growth by arsenic trioxide between BEL-7402 and SMMC-7721 cell lines, the cause of which may be due to the difference in GSH content in BEL-7402 and SMMC-7721 cells.     

Effects of zinc on biological behavior of hepatocellular carcinoma cell line BEL-7404

AIM: To observe the effects of exogenous zinc on the biological behavior of hepatocellular carcinoma (HCC) cell line BEL-7404. METHODS: BEL-7404 cells were cultured with zinc sulfate at various concentrations. The intracellular concentration of zinc, cell viability, cell cycle, cell apoptosis and migration and invasion abilities were measured by TSQ fluorescent probe, MTT assay, DNA ploid analysis, acridine orange/ethidium bromide fluorescence staining and Transwell assay, respectively. The mRNA and protein expression levels of albumin in the BEL-7404 cells were determined by real-time PCR and Western blot, respectively. RESULTS: With the elevated concentration of zinc in culture condition, the concentration of zinc in the BEL-7404 cells was increased (P<0.05). The cell viability and migration and invasion abilities were decreased, while the apoptotic rate was increased (P<0.05). The cells in G₀/G₁ phase were decreased, while the cells in G₂/M phase were increased. Additionally, the mRNA and protein expression of albumin also increased (P<0.05). CONCLUSION: The zinc ion inhibits the cell viability as well as migration and invasion abilities, blocks the cells in G₂/M phase, and may reduce cell malignant phenotype.     

Effects of down-regulation of protein kinase C on activation of store-operated Ca2+ channels and the proliferation of airway smooth muscle cells

AIM: To investigate the effects of down-regulation of protein kinase C (PKC) on the activity of store-operated Ca2+ channels (SOC) and the proliferation of airway smooth muscle cells (ASMCs). METHODS: Rat bronchial smooth muscle cells were isolated and cultured. Fluo-3/AM fluorescence was measured by laser confocal microscope to assessing intracellular Ca2+. Down-regulation of PKC activity was achieved by incubation of ASMCs with PKC activator phorbol-12-myristate-13-acetate (PMA, 10 μmol/L) or phorbol 12, 13-dibutyrate (PDBu, 1 μmol/L) for 24 h. The proliferation of ASMCs was assayed by calculating the reduction rates of Alamar blue. RESULTS: Down-regulation of PKC activity by long-term exposure of PMA or PDBu inhibited the proliferation of ASMCs, the similar results were obtained by using PKC inhibitor chelerythrine. Both down-regulation of PKC activity and inhibition of PKC activity by chelerythrine reduced Ca2+ entry through SOC channels. Low concentration of PMA (0.1 μmol/L) promoted the proliferation of ASMCs, and this effect was inhibited by SOC blocker SKF-96365. CONCLUSION: Inhibition or down-regulation of PKC activity results in the inhibition of SOC channels, suggesting that PKC is involved in the activation of these channels. Ca2+ entry through SOC channels might contribute to PKC-promoted proliferation of ASMCs.     

Effects of sulphated heparin on proliferation and apoptosis of human hepatocellular carcinoma cell line (HepG2)

AIM:To explore the effect and the mechanism of sulphated heparin on the proliferation and the apoptosis of human hepatocellular carcinoma cells.METHODS:The human hepatocellular carcinoma cell line (HepG-2) was used to identify the expression ofrasgene protein and to study the effect of sulphated heparin on proliferation and the apoptosisin vitro.RESULTS:The sulphated heparin downregulated the ras protein expression and inhibited the cell growth in HepG2 cells. In the presence of sulphated heparin, the apoptosis rate of HepG2 increased.CONCLUSION:The data suggest that the effects of sulphated heparin on the proliferation and the apoptosis of the human hepatocellular carcinoma cell are correlated with the signaling transduction mediated byrasgene protein.     

Effect of nuclear factor-κB on proliferation of airway smooth muscle cells regulated by protein kinase C in asthmatic rats

AIM: To investigate the effect of protein kinase C (PKC)- nuclear factor-κB (NF-κB) signal pathway on proliferation of airway smooth muscle cells (ASMCs) in asthmatic rats.METHODS: (1) 16 Wistar rats were divided into asthmatic group (8 rats) and control group (8 rats).ASMCs from asthmatic group and control group were treated with PKC agonist PMA and NF-κB inhibitor PDTC.The proliferation of ASMCs was examined by cell cycle analysis,MTT colorimetric assay and proliferating cell nuclear antigen (PCNA) immunofluorescence staining,respectively.NF-κB activity was detected by NF-κB p65 immunofluorescence staining and electrophoretic mobility shift assay (EMSA),respectively.RESULTS: The percentage of S phase,A value,the positive expression rate of PCNA,the positive expression rate of NF-κB p65 and EMSA value in asthmatic ASMCs treated with PMA were higher than those in asthmatic ASMCs without treatment (P<0.05).After asthmatic ASMCs previously treated with PDTC,then with PMA,the above figures were lower than those in asthmatic ASMCs only treated with PMA and without treatment (P<0.05).The above figures in asthmatic ASMCs only treated with PDTC were lower than those in asthmatic ASMCs without treatment (P<0.05).CONCLUSION: NF-κB may contribute to the proliferation of ASMCs in asthmatic rat,in which PKC－NF-κB signal pathway is involved.     

Expression of eEF1A2 in hepatocellular carcinoma

AIM: To study the expression of eukaryotic elongation factor 1A2 (eEF1A2) in the hepatocellular carcinoma (HCC) tissues and the effects of eEF1A2 over-expression on the biological behaviors of the HCC cells. ME-THODS: The expression of eEF1A2 at mRNA and protein levels in the HCC tissues and matched liver tissues from 62 HCC patients, and 20 normal liver tissues were detected by the methods of real-time PCR and immunohistochemical staining, respectively. The mRNA and protein expression of eEF1A2 in the HCC cells was also determined by real-time PCR and Western blot, respectively. The lentivirus containing eEF1A2 gene was constructed, and was used to infect the HCC cells with low eEF1A2 expression. The expression of eEF1A2 at mRNA and protein levels in the infected cells was detected by real-time PCR and Western blot, respectively. The cell activity, cell cycle and mRNA expression of albumin were measured by MTT assay, DNA ploid analysis and real-time PCR, respectively.RESULTS: The mRNA expression levels and protein expression positive rates of eEF1A2 in the 62 cases of HCC tissues, were significantly higher than those of 62 matched liver tissues and 20 normal liver tissues (P<0.01). eEF1A2 mRNA and protein were highly expressed in SMMC-7721 cells and BEL-7402 cells, and expressed in SK-HEP-1 cells at low level. The expression of eEF1A2 at mRNA and protein levels in the SK-HEP-1 cells was significantly enhanced by infection of GV287-eEF1A2 expression lentivirus.Compared with negative control group (transfected with negative control lentivirus), the cell activity in eEF1A2 over-expression group (transfected with GV287-eEF1A2 expression lentivirus) was significantly enhanced, the mRNA expression of albumin was remarkably reduced, and the cells in G₀/G₁ phase were significantly decreased with increased percentage of the cells in S and G₂/M phases.CONCLUSION: eEF1A2 is selectively over-expressed in human HCC cancer tissues. eEF1A2 might be a putative oncoprotein in HCC. eEF1A2 over-expression has noticeable effects on the HCC cell proliferation enhancement, differentiation inhibition, and cell cycle acceleration through the G₀/G₁ phase to S phase and G₂/M phases.     

Effect of extract of Oratosquilla oratoria on telomerase activity in human nasopharyngeal carcinoma cell line

AIM: To study the inhibitory effect and its mechanisms of the extract of Oratosquilla oratoria (EOS) on the activity of telomerase in human nasopharyngeal carcinoma cell line CNE-2Z. METHODS: MTT assay was used to determine the effect of different doses of EOS on the proliferation of CNE-2Z cells. The activity of telomerase was analyzed by TRAP-ELISA. The mRNA expression of hTERT was determined by RT-PCR, and the protein expression of c-Myc was detected by Western blotting. RESULTS: EOS inhibited the proliferation of CNE-2Z cells in a dose-dependent manner (P<0.01). Telomerase activity was decreased, the mRNA expression of hTERT and c-Myc in CNE-2Z cells was also decreased (P<0.01) by the treatment of EOS. The correlation between the down-regulatory expression of hTERT mRNA and inhibitory expression of c-Myc protein (P<0.05) under the condition of EOS exposure was observed. CONCLUSION: EOS inhibits the proliferation of CNE-2Z cells by reducing the activity of telomerase, which is related with the inhibitory expression of hTERT mRNA caused by the decrease in c-Myc production.     

Regulation of octreotide on SSTR2 expression in hepatocellular carcinoma

AIM: To observe the regulation of octreotide (OCT) on the expression of somatostatin receptor 2 (SSTR2) in Bel7402 hepatocellular carcinoma (HCC) cells, and the inhibition effect of OCT on the growth of HCC. METHODS: The effect of OCT on proliferative ability of Bel7402 cells was observed by MTT assay. The cell form was observed by light invert microscope. The adhesive and invasive ability was detected by cell adhesion and migration experiments. The cell cycle, SSTR2 expression of 7402 cells were determined by immunofluorescence flow cytometry. Nude mice bearing xenografts in situ were treated with OCT or saline control for 7 weeks since tumor implantation. The immunohistochemistry for SSTR2 was performed. SSTR2 mRNA expression in cell line and xenografts was measured by semi-quantitative RT-PCR. RESULTS: After OCT treatment, the proliferative ability and cell form of 7402 cells didn't change significantly. The adhesive and invasive ability decreased significantly. The ratio of cells in resting state (G₀/G₁) increased, but no apoptosis peak was observed. The SSTR2 expression on 7402 cell membranes decreased significantly. SSTR2 expression in cell line of OCT group was higher than control group, but there was no significant difference between them. The mean tumor weight in mice given OCT was significantly lower than that in control group. SSTR2 immunostaining in tumor cells of treatment group showed stronger positivity, compared with control group. SSTR2 mRNA expression in xenografts after OCT treatment was significantly higher than that in control group. CONCLUSIONS: OCT inhibits the growth of HCC through SSTR2. SSTR2 is regulated by its ligand, the long-term OCT treatment increases the SSTR2 expression and enhances the effect of inhibiting HCC, however, short-term treatment may induces its desensitization and the decrease in anti-tumor effect.     

Role of IGF-Ⅱ in proliferation and migration of hepatocellular carcinoma Huh7 cells

AIM: To observe the effects of insulin-like growth factorⅡ (IGF-Ⅱ) at different expression levels on hepatocellular carcinoma Huh7 cell proliferation and migration, and to explore the role of IGF-Ⅱ in the development of HCC. METHODS: The Huh7 cells were transfected with the over-expression plasmid pcDNA3.1(+)- IGF-Ⅱ or RNA interference plasmid pLVX-shRNA-IGF-Ⅱ by Lipofectamine 2000. The quantitative real-time PCR and Western blotting were used to verify the expression of IGF-II. The biological behaviors of the Huh7 cells were analyzed by CCK-8 assay, plate clone formation assay, cell scratch test and Transwell chamber experiment.RESULTS: Over-expression of IGF-II promoted the growth and migration of hepatocellular carcinoma cells (P < 0.05), and the cell proliferation was significantly inhibited in the Huh7 cells with low IGF-II expression (P < 0.05).CONCLUSION: IGF-II is involved in the regulation of biological behavior of hepatocellular carcinoma Huh7 cells in vitro, which may play a promoting role in the development of hepatocellular carcinoma.     

High glucose up-regulates TRAIL-R4 expression in THP-1 cells and smooth muscle cells

AIM: To evaluate the expression of TNF-related apoptosis inducing ligand receptor 4 (TRAIL-R4) of THP-1 cells and human aorta smooth muscle cells under high glucose intervention. METHODS: Monocytic cell line THP-1 was incubated with PMA to induce to mature macrophage, Adhesion molecules CD11b and CD11c were assessed by FACS. TRAIL-R4 levels in THP-1 cells treated with different glucose concentrations were determined by Western blotting. The changes of TRAIL-R4 protein expressions were observed at different time points in human aorta smooth muscle cells. Western blotting was employed to evaluate TRAIL-R4 levels after the intervention of PKC activator. RESULTS: Incubation with 160 nmol/L PMA induced mature macrophages. TRAIL-R4 expression was up-regulated after incubation with 20 mmol/L glucose in macrophages. TRAIL-R4 was elevated in a time course manner under high glucose level in human aorta smooth muscle cells. Moreover, activation of PKC induced TRAIL-R4 expressions. CONCLUSION: Up-regulated TRAIL-R4 protein levels induced by high glucose levels might inhibit apoptosis of monocytes and smooth muscle cells and contribute to the progression of atherosclerosis.     

Lysophosphatidic acid (LPA) induces the proliferation of astrocytes in rat via pathway of protein kinase C-α and calcium ion in vitro

AIM: To determine if lysophosphatidic acid (LPA) regulates the proliferation of astrocytes (AS) and to approach the mechanism of the process.METHODS: The cerebral AS of the neonatal SD rats were cultured in vitro and divided randomly into control group, PKC excitomotor (PMA) group, LPA group, PKC-α inhibitor (Ro31-8220) group, Ro31-8220+PMA group and Ro31-8220+LPA group. The proliferation of the cells was detected by MTT assay and flow cytometry (FCM). The concentration of intra-cellular calcium ion of the cells (［Ca2＋］i) which were labeled with Fura-2/AM was determined by ultraviolet spectrophotometer. The change of PKC-α inside the cells was observed by Western blotting.RESULTS: LPA and PMA stimulated the proliferation of AS, they also enhanced the expression of PKC-α and increased the concentration of ［Ca2＋］i. After pretreated with Ro31-8220, the abilities of LPA that mentioned above were decreased. The change of ［Ca2＋］i was associated with the diversity of PKC-α.CONCLUSION: LPA promotes the proliferation of AS via the way of PKC-α and Ca2＋.