Effects of SM22α on migration and invasion abilities of colorectal cancer cells

AIM:To explore the effects of smooth muscle 22α protein (SM22α) on the migration and invasion abilities of colorectal cancer cells, and to investigate its molecular mechanism. METHODS:The SM22α-over-expressing cells were constructed by lentivirus transfection. The cell migration ability was detected by wound healing assay. The changes of cell migration and invasion abilities were measured by Transwell assay. RT-qPCR was used to detect the changes of SM22α mRNA level. The protein levels of extracellular signal-regulated kinase (ERK), p-ERK, matrix metalloproteinase-9 (MMP-9) and SM22α were determined by Western blot. RESULTS:HCT116 cells with SM22α over-expression were constructed successfully. SM22α inhibited the migration and invasion abilities of colorectal cancer cells. SM22α over-expression decreased the protein levels of p-ERK and MMP-9 (P<0.05).CONCLUSION:SM22α inhibits the migration and invasion abilities of colorectal cancer cells by inhibiting ERK/MMP-9 signaling pathways.     

Sinomenine inhibits viability,migration and invasion of human ovarian cancer SKOV3 cells

AIM:To investigate the effect of sinomenine on the viability, migration and invasion of human ovarian cancer SKOV3 cells and its possible mechanism. METHODS:The SKOV3 cells were treated with sinomenine at different concentrations for 12 h, 24 h and 48 h. CCK-8 assay was employed to detect the effects of sinomenine on the viability of the SKOV3 cells. Flow cytometry was used to analyze the cell cycle distribution. The cell migration and invasion abilities were measured by Transwell assay. Western blot was used to determine the protein levels of cyclin A, cyclin D1, E-cadherin and matrix metalloproteinase-9 (MMP-9). RESULTS:Sinomenine remarkably inhibited the viability of SKOV3 cells and IOSE80 cells in a time-dependent and dose-dependent manner (P<0.05), and the IC₅₀ values of 48 h were 2.12 mmol/L and 17.35 mmol/L, respectively. In a dose-dependent manner, sinomenine induced G₀/G₁ and S phase arrest in SKOV3 cells (P<0.05), suppressed the migration and invasion abilities of SKOV3 cells (P<0.05), down-regulated the protein levels of cyclin A, cyclin D1 and MMP-9 (P<0.05), and up-regulated the protein level of E-cadherin (P<0.05). CONCLUSION:Sinomenine inhibits the viability, migration and invasion of human ovarian cancer SKOV3 cells most likely via down-regulation of the protein levels of cyclin A, cyclin D1 and MMP-9, and up-regulation of the protein level of E-cadherin.     

Effects of NOB1 gene silencing on drug sensitivity and invasion and migration abilities of human colon cancer SW480 cells

AIM:To investigate the effect of NOB1 gene expression knock-down by transfection of small interfering RNA (siRNA) on the viability, drug sensitivity, apoptosis, cell cycle distribution, and invasion and migration abilities of human colon cancer SW480 cells. METHODS:NOB1 siRNA was transfected into SW480 cells using Lipofectamine 3000. The mRNA and protein levels of NOB1 in the SW480 cells were determined by real-time PCR and Western blot. The cell viability and sensitivity to different chemotherapeutic drugs (cisplatin, 5-fluorouracil, oxaliplatin and capecitabine) were detected by MTT assay after knock-down of NOB1 gene expression in the SW480 cells. The apoptosis and cell cycle distribution of SW480 cells were analyzed by flow cytometry. The invasion and migration abilities of SW480 cells were detected by Transwell assay. RESULTS:After transfection with NOB1 siRNA, the mRNA and protein levels of NOB1 in the SW480 cells were significantly decreased (P<0.05). Compared with control group and control siRNA group, the viability of SW480 cells in NOB1 siRNA group was significantly decreased at 24~72 h. The half maximal inhibitory concentrations of the chemotherapy drugs cisplatin, 5-fluorouracil, oxaliplatin and capecitabine were significantly decreased. The apoptotic rate was significantly increased and the cell cycle were blocked. The cell invasion and migration abilities were significantly reduced (P<0.05). CONCLUSION:Knock-down of NOB1 gene expression inhibits the viability and invasion and migration abilities of colon cancer SW480 cells, and promotes drug sensitivity and apoptosis. NOB1 may be a new target for diagnosis and treatment of colon cancer.     

High mobility group box 1 protein promotes proliferation,migration and invasion of colon cancer cells

AIM: To investigate the expression of high mobility group box 1 protein (HMGB1) in colon can-cer cells, and to determine its regulatory roles in colon cancer cell proliferation, migration and invasion. METHODS: qPCR and Western blot were used to quantify the mRNA and protein expression levels of HMGB1 in human colon cancer SW620 cells and normal colonic epithelial FHC cells. HMGB1 shRNA was transfected into the SW620 cells to establish the stable HMGB1-downregulating colon cancer cells (shHMGB1 group), and negative control (shNC) group and blank control (blank) group were also set up. The proliferation, migration and invasion of the cells were determined by CCK-8 assay, colony formation experiment and Transwell chamber assays. Western blot was used to determine the protein levels of p-ERK, ERK, c-Myc, matrix metalloproteinase (MMP)-2/9, E-cadherin, N-cadherin, Bcl-2 and Bax. RESULTS: Both of the mRNA and protein levels of HMGB1 in colon cancer cells were higher than those in the normal colonic epithelial cells (P<0.05). HMGB1 gene was successfully knocked down in SW620 cells. Compared with blank group and shNC group, the proliferation, migration and invasion abilities of the cells in shHMGB1 group were significantly inhibited (P<0.05). The protein levels of MMP-2, MMP-9, N-cadherin, c-Myc, Bcl-2 and p-ERK were reduced notably, while the expression of Bax protein was increased (P<0.05) in shHMGB1 group compared with shNC group and blank group.CONCLUSION: HMGB1 effectively promotes the proliferation, migration and invasion of colon cancer cells through ERK/c-Myc signaling pathway.     

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.     

CHK1 inhibitor SCH900776 suppresses proliferation and migration of U251 cells

AIM: To investigate the effect of SCH900776, an inhibitor of checkpoint kinase 1 (CHK1), on the proliferation and migration abilities of human glioma U251 cells.METHODS: The cell viability was detected by MTT assay, and cell proliferation was determined by cell colony formation assay. Cell cycle distribution was analyzed by flow cytometry. Wound healing assay was used to determine the cell migration ability. The protein levels were determined by Western blot.RESULTS: SCH900776 inhibited the growth of U251 cells in a dose-dependent manner (P<0.05). SCH900776 treatment substantially induced U251 cell cycle arrest in S and G₂/M phases by decreasing the level of cell division cycle protein 2 (Cdc2) and p-Cdc2. Moreover, SCH900776 inhibited the cell migration. Western blot results indicated that SCH900776 increased the phosphorylation level of p38 MAPK and inhibited the activation of Akt.CONCLUSION: SCH900776 inhibits the proliferation and migration abilities in human U251 cells by promoting the phosphorylation of p38 MAPK and suppressing the activation of Akt.     

Effect of FGFR1 expression knock-down on biological characteristics of infantile hemangioma endothelial cells

AIM: To study the effect of fibroblast growth factor receptor 1 (FGFR1) expression knock-down on the viability, apoptosis, invasion and migration of infantile hemangioma endothelial cells (HemECs). METHODS: FGFR1 was down-regulated by FGFR1 small interfering RNA (si-FGFR1) transfection. The viability of the cells was measured by CCK-8 assay. The apoptotic rate was analyzed by flow cytometry and the invasion and migration abilities were determined by Transwell assay. The protein levels of phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), and phosphorylated AKT (p-AKT) were examined by Western blot. RESULTS: Transfection of si-FGFR1 into HemECs had significant effects on inhibiting cell viability (P<0.05), promoting apoptosis (P<0.05), and decreasing cell invasion and migration abilities (P<0.05). The results of Western blot showed that knockdown of FGFR1 gene expression in the cells reduced the protein levels of PI3K and p-AKT (P<0.05), and had no significant effect on AKT protein level. CONCLUSION: Knock-down of FGFR1 expression changes the biological characteristics of endothelial cells in infantile hemangiomas by regulating PI3K/AKT signaling pathway.     

Effects of CENP-W down-regulation on human glioma U87 cells

AIM: To study the effect of centromere protein W (CENP-W) down-regulation on human glioma U87 cells.METHODS: Small interfering RNA (siRNA) was used to inhibit the expression of CENP-W in the U87 cells. The interference effect of siRNA was evaluated by RT-qPCR and Western blot. The proliferation of the cells was analyzed by MTT assay, BrdU staining and colony formation experiment. Transwell chamber assay was used to detect the invasion ability of the cells. The cell migration ability was measured by a scratch test. The changes of the cell cycle distribution and apoptosis were analyzed by flow cytometry.RESULTS: The results of MTT assay, colony formation experiment and BrdU staining showed that the cell proliferation and colony formation abilities in experimental group were significantly lower than those in control group and negative control group. The results of Transwell and scratch experiments showed that the migration and invasion abilities in experimental group were weaker than those in blank control group and negative control group. The results of flow cytometry analysis showed that the cell cycle distribution in experimental group was arrested in G₀/G₁ phase. The percentage of apoptotic cells in experimental group was higher than that in control group (P<0.05).CONCLUSION: Down-regulation of CENP-W expression inhibits the proliferation, migration and invasion of human glioma cells and promotes the apoptosis of the cells, suggesting that CENP-W may be a potential target of gene therapy for human glioma.     

Effect of serum amyloid A on invasion,migration and MAPK signaling pathway in osteosarcoma cells

AIM: To investigate the effect of silencing of serum amyloid A (SAA) on the viability, apoptosis, migration and mitogen-activated protein kinase (MAPK) signaling pathway in osteosarcoma U2OS cells. METHODS: Small interfering RNA (siRNA) targeting SAA was transfected into U2OS cells to silence the expression of SAA gene. The U2OS cells were divided into blank control group, negative control group, and experimental group. The cells in negative control group and experimental group were transfected into negative control siRNA and SAA-siRNA, respectively. The cells in blank control group were without any treatment. The viability of the cells was measured by MTT assay and the apoptotic rate was analyzed by flow cytometry with Annexin V-FITC/PI double staining. The migration and invasion abilities of the cells were detected by Transwell chamber assay. The protein levels of SAA, phosphorylated p38 MAPK (p-p38 MAPK) and phosphorylated c-Jun N-terminal kinase (p-JNK) in the cells were determined by Western blot. RESULTS: The protein expression of SAA in SAA-siRNA group was significantly lower than that in blank control group (P<0.05). Compared with blank control group, the cell viability in SAA-siRNA group was significantly decreased (P<0.05), the apoptotic rate was significantly increased (P<0.05), and the invasion and migration abilities were significantly decreased (P<0.05). The protein levels of p-p38 MAPK and p-JNK in SAA-siRNA group were significantly lower than those in blank control group (P<0.05), and no significant difference of total JNK and p38 protein levels was observed. CONCLUSION: Silencing of SAA expression inhibits the viability of osteosarcoma cells, induces apoptosis and decreases the migration of osteosarcoma cells, which may be related to the activation of MAPK signaling pathway.     

Cordycepin inhibits proliferation and migration of gallbladder cancer cell SNU-308 by ERK1/2, Ezrin and Akt signaling pathways

AIM: To investigate the effects of cordycepin on the proliferation and migration abilities of gallbladder cancer cell line SNU-308 and its molecular mechanism. METHODS: The viability of SNU-308 cells treated with cordycepin at different concentrations was measured by MTT assay and the colony formation ability was also detected. The effect of cordycepin on apoptosis was analyzed by flow cytometry with Annexin V/PI double staining. The protein levels of apoptosis and autophagy markers, and the phosphorylation level of Akt, ERK1/2 and Ezrin were evaluated by Western blot. Immunofluorescence staining was also used to analyze the expression level of LC3 after cordycepin treatment. Wound healing assay and Transwell assay were performed to evaluate the migration ability of the SNU-308 cells after cordycepin treatment. Wound healing assay was also used to evaluate the effects of Akt inhibitor, ERK1/2 inhibitor and Ezrin knockdown on the changes of migration ability. RESULTS: Cordycepin significantly inhibited the viability and the ability of colony formation of gallbladder cancer cells (P<0.05). Induction of apoptosis by cordycepin were revealed by flow cytometry (P<0.05). The protein expression of Bcl-2 was down-regulated, while the protein levels of Bax, cytochrome C (Cyto C), Fas, FasL and cleaved caspase-3 were increased and the autophagy marker beclin 1 and the ratio of LC3-Ⅱ/I were upregulated by Western blot analysis (P<0.05). LC3 accumulation in the cytoplasm after cordycepin treatment was demonstrated by immunofluorescence staining. Cordycepin treatment resulted in the inhibition of cell migration were detected by Transwell assay and wound healing assay (P<0.05). The protein levels of p-Akt, p-ERK1/2 and p-Ezrin were down-regulated after cordycepin treatment (P<0.05). Besides, Ezrin knockdown, Akti-1/2 and GDC-0994 all resulted in the inhibition of migration ability (P<0.05). CONCLUSION: Cordycepin induces apoptosis and autophagy to inhibit gallbladder can-cer cell proliferation and migration by regulating ERK1/2, Ezrin and Akt signaling pathways.     

Genistein inhibits proliferation of human oral cancer TCA8113 cells through suppression of VEGF expression

AIM: To investigate the effect of genistein on the proliferation of human oral cancer TCA8113 cells and to explore the underlying mechanisms.METHODS: The cell proliferation was examined by MTT assay, cell counting and colony formation assay. Western blotting was employed to examine the protein levels of vascular endothelial growth factor(VEGF), extracellular signal-regulated kinase(ERK) and p-ERK. RESULTS: Genistein significantly inhibited the proliferation of TCA8113 cells in a concentration-dependent fashion. Moreover, genistein dose-dependently decreased the protein levels of VEGF, ERK and p-ERK. The expression of VEGF was also blunted by U0126, a specific inhibitor of ERK. U0126 and axitinib, a VEGF receptor antagonist, both significantly inhibited the proliferation of TCA8113 cells. CONCLUSION: Genistein inhibits the proliferation of TCA8113 cells, which may be related to its inhibitory effect on ERK expression and activation, thus subsequently decreasing the expression of VEGF.     

PGRN gene silencing on proliferation and migration abilities of human non-small-cell lung cancer A549 cells

AIM: To investigate the effect of small interfering RNA (siRNA)-mediated progranulin (PGRN) gene silencing on the proliferation and migration abilities of human non-small-cell lung cancer A549 cells and its mechanism. METHODS: The mRNA and protein expression levels of PGRN in the A549 cells and human bronchial epithelial (HBE) cells were detected by qPCR and Western blot. A549 cells were transfected with PGRN-siRNA by liposome method. The expression of PGRN at mRNA and protein levels in the A549 cells transfected with PGRN-siRNA was detected by qPCR and Western blot, respectively. The cell viability was measured by MTT assay. The cell proliferation ability was measured by living cells counting and crystal violet staining assays. The cell migration ability was measured by wound-healing and Transwell assays. The protein levels of proliferating cell nuclear antigen (PCNA), cyclin D1, Bcl-2 and Bax were determined by Western blot. The protein levels of phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) and phosphorylated protein kinase B (p-Akt) were also determined by Western blot. RESULTS: The expression of PGRN at mRNA and protein levels was higher in the A549 cells than that in the HBE cells (P<0.05). The expression of PGRN at mRNA and protein levels in the A549 cells transfected with PGRN-siRNA was significantly decreased, and the cell proliferation and migration abilities were significantly decreased. The protein expression levels of PCNA, cyclin D1 and Bcl-2 were significantly reduced and the protein expression level of Bax was significantly increased (P<0.05). Meanwhile, the protein levels of p-ERK1/2 and p-Akt were down-regulated (P<0.05). CONCLUSION: PGRN gene silencing obviously inhibits the proliferation and migration abilities of human non-small-cell lung cancer A549 cells. The PI3K/Akt and MAPK/ERK signaling pathways may play an important role in these processes.     

Effects of marrow stromal cell-mediated microenvironment on human lung adenocarcinoma A549 cells

AIM: To investigate the effects of marrow stromal cell line HS-5 on human lung adenocarcinoma A549 cells in the tumor microenvironment. METHODS: The effects of HS-5 cell-conditioned medium (HS-5-CM) on the viability and migration ability of A549 cells were detected by MTT assay and wound-healing assay. After treatment with HS-5-CM, the expression of CX3C chemokine receptor 1 (CX3CR1) at mRNA level in the A549 cells was examined by qPCR. The protein levels of p-ERK and ERK in the A549 cells treated with MAPK/ERK pathway inhibitor U0126 were observed by Western blot, the migration ability of the A549 cells was measured by wound-healing assay, and the protein expression of CX3CR1 was determined by Western blot. RESULTS: HS-5-CM promoted the viability and migration ability of the A549 cells (P<0.01). The expression of CX3CR1 at mRNA level in the A549 cells was increased after treatment with HS-5-CM. MAPK/ERK inhibitor U0126 inhibited the activation of MAPK/ERK signaling pathway (P<0.01), and reduced the migration ability (P<0.01) and the expression of CX3CR1 (P<0.05) in the A549 cells. CONCLUSION: HS-5-CM significantly promotes the A549 cell viability and migration ability. Activation of MAPK/ERK signaling pathway and the expression of CX3CR1 may play a important role in this process.     

Effects of lupeol and miR-145-5p on proliferation and apoptosis of prostate carcinoma cells

AIM To investigate the effect of lupeol combined with microRNA-145-5p (miR-145-5p) on the proliferation and apoptosis of prostate carcinoma LNCaP cells. METHODS After hsa-miR-145-5p and lupeol were applied to LNCaP cells for 24, 48 and 72 h, the cell viability inhibitory rate was detected by MTT assay. PI single staining plus flow cytometry was used to detect the cycle distribution. The flow cytometry with annexin V/PI double staining and TUNEL experiment were used to detect apoptosis. Transwell method was used to detect cell migration and invasion abilities. Wound healing experiment was used to detect cell migration ability. The cell colony formation assay was used to calculate the colony formation inhibitory rate. RESULTS The cells in cell control group, non-specific control group and solvent group did not show effective LNCaP cell viability inhibition, migration inhibition and invasion inhibition, while the viability, migration and invasion abilities were significantly inhibited, and early apoptosis in vitro were induced in hsa-miR-145-5p group and lupeol group. In particular, the combination (hsa-miR-145-5p+lupeol) group showed more effective proliferation inhibition than the single-drug groups. CONCLUSION Both hsa-miR-145-5p and lupeol inhibit the proliferation, migration and invasion of LNCaP cells, and induce early apoptosis in vitro. Lupeol enhances the proliferation-inhibitory and apoptosis-inducing effects of hsa-miR-145-5p on LNCaP cells.     

Effect of HC-1119 on biological behaviors of triple-negative breast cancer BT549 cells

AIM: To explore the effect of new artificially synthesized androgen receptor (AR) antagonist HC-1119 on the biological function of triple-negative breast cancer (TNBC) BT549 cells and the molecular mechanism. METHODS: The AR expression was assessed in different human breast cancer cell lines MDA-MB-231, T47D, MCF-7, SKBR3 and BT549 by Western blot. The TNBC BT549 cells with AR positive expression were treated with HC-1119. The cell viability was measured by CCK-8 assay. The apoptosis rate and cell cycle distribution were analyzed by flow cytometry. The migration and invasion abilities were detected by Transwell assay in vitro. The protein expression of E-cadherin, vimentin and P21 was determined by Western blot. RESULTS: AR was positively expressed in BT549 cells. HC-1119 inhibited the cell viability in a time-and dose-dependent manner (P<0.05), increased the percentage of apoptotic cells and the percentage of S-phase cells significantly, repressed the migration and invasion abilities (P<0.05), and decreased P21 expression at protein level (P<0.01). No influence on the expression of E-cadherin and vimentin in the BT549 cells was observed. CONCLUSION: AR antagonist HC-1119 decreases the viability, migration ability and invasion ability, enhances the apoptosis, and arrests the cell cycle distribution of TNBC BT549 cells. HC-1119 represses the viability of BT549 cells by down-regulating P21 expression, while the process of epithelial-mesenchymal transition is not involved in the inhibition of cell migration.     

Effect of ABCE 1 gene silencing on proliferation and migration of human bladder cancer cell line T24

AIM: To investigate the effect of small interfering RNA (siRNA)-mediated ABCE1 knockdown on the survival, cell cycle and invasion of human bladder cancer cell line T24. METHODS: The siRNA against ABCE1 was constructed and transfected into the T24 cells with Lipofectamine^TM 2000. The expression of ABCE1 was detected by RT-PCR and Western blot. Flow cytometry was used to detect the cell cycle. The effects of ABCE1 gene silencing on proliferation, migration and invasion of T24 cells were evaluated by CCK-8 assay, wound-healing assay and Transwell invasion assay, respectively. RESULTS: Compared with control group and blank group, the mRNA and protein levels of ABCE1 were significantly decreased in experimental group after transfected with ABCE1 siRNA. The cell cycle was arrested at G₀/G₁ phase and the cell number in S phase was decreased in the T24 cells. Compared with control group and blank group, the proliferation of T24 cells in experimental group was inhibited significantly, and the migration and invasion abilities of T24 cells in experimental group decreased significantly. CONCLUSION: Knockdown of ABCE1 gene may decrease migration, invasion and proliferation abilities in T24 cells.     

Rab1A knockdown inhibits malignant biological behaviors of breast carcinoma cells by inhibiting phosphorylation of AKT

AIM: To investigate the role of Rab1A gene in the malignant biological behaviors of breast carcinoma cells. METHODS: The expression levels of Rab1A in breast carcinoma tissues and normal adjacent tissues, and the basic expression level of Rab1A in different breast carcinoma cell lines were measured by Western blot. Small interfering RNA (siRNA) targeting Rab1A was designed, synthetized and transfected into the breast carcinoma MDA-MB-231 cells. After validation of efficiency of Rab1A gene expression knock-down, the malignant biological behaviors of the MDA-MB-231 cells were measured by CCK-8 assay, wound healing assay, Transwell assay and flow cytometry. The protein levels were determined by Western blot. RESULTS: Rab1A was expressed in normal breast tissue and cells at low level, and at high level in the cancer tissues and cancer cells (P<0.05). Compare with control group, after knock-down of Rab1A expression, the viability of MDA-MB-231 cells was significantly inhibited (P<005), the abilities of migration and invasion were reduced (P<0.05), the apoptosis was decreased (P<0.05), the percentage of G²/M phase was increased, the protein levels of p53, Bax, cleaved caspase-3 and PTEN were significantly increased (P<0.05), and the protein levels of Bcl-2, cyclin D1, cyclin B1, matrix metalloproteinase 2 (MMP2), p-AKT and mTOR were significantly decreased (P<0.05). CONCLUSION: Rab1A modulates the breast carcinoma cell viability, inhibits the migration and invasion abilities, induces G² arrest and effectively regulates the cell growth-, cell cycle-and apoptosis-related proteins. Knock-down of Rab1A expression inhibits the evolution and development of breast cancer by inhibiting the phosphorylation of AKT pathway, and Rab1A may function as a potential target in breast carcinoma treatment.     

Effect of PARP-1 on cisplatin resistance in breast cancer MCF-7 cells

AIM: To study the effect of poly(ADP-ribose) polymerase-1 (PARP-1) on cisplatin resistance of human breast cancer MCF-7 cells and its possible mechanisms.METHODS: The expression of PARP-1 at mRNA and protein levels in MCF-7 cells and MCF-7/DDP cells was determined by real-time PCR and Western blot. The expression of PARP-1 in the MCF-7/DDP cells was blocked by PARP-1 siRNA. The cell viability and apoptosis were detected by the CCK-8 assay and flow cytometry analysis, respectively. Furthermore, the protein levels of PARP-1, Bcl-2, Bax, cleaved caspase-3, caspase-3, cytochrome C (Cyto-C), extracellular signal-regulated kinase (ERK) and phosphorylated ERK (p-ERK) were detected by Western blot.RESULTS: The expression of PARP-1 at both mRNA and protein levels was significantly up-regulated in the MCF-7/DDP cells. The expression of PARP-1 was increased in the MCF-7 cells treated with cisplatin. Knockdown of PARP-1 induced the apoptosis of MCF-7/DDP cells with an increased sensitivity to cisplatin. Meanwhile, knockdown of PARP-1 down-regulated the protein levels of Bcl-2/Bax and p-ERK, but up-regulated the protein levels of cleaved caspase-3 and Cyto-C. After incubated with a specific ERK inhibitor U0126, the cell viability in PARP-1 siRNA group was down-regulated significantly.CONCLUSION: Knockdown of PARP-1 increases the sensitivity of MCF-7/DDP cells to cisplatin, and promotes the cell apoptosis via mitochondrial apoptosis pathway. The mechanism may be related to the attenuation of ERK signaling pathway by inhibiting phosphorylation of ERK.     

Kaempferol inhibits cell proliferation,invasion and migration via Wnt/β-catenin signaling in HBx-HepG2 cells

AIM: To explore the effects of kaempferol on the proliferation, invasion and migration abilities of HBx-HepG2 cells and to examine the underlying molecular mechanisms. METHODS: The expression levels of related genes at mRNA and protein levels were determined by RT-qPCR and Western blot. The cell apoptotic rate was analyzed by flow cytometry. The cell proliferation, growth, invasion and migration abilities were measured by MTT assay, colony formation assay, Transwell invasion assay and wound healing assay, respectively. RESULTS: Kaemferol inhibited HBx-HepG2 cell proliferation in a concentration-and time-dependent manner. Kaempferol at 100 μmol/L significantly inhibited the colony formation, invasion and migration abilities of the HBx-HepG2 cells. Kaemferol at 100 μmol/L also increased cell apoptotic rate, increased the protein levels of cleaved caspase-3, cleaved caspase-9 and Bax, and decreased the expression level of Bcl-2. In addition, kaemferol at 100 μmol/L suppressed the mRNA and protein expression levels of β-catenin, c-Myc and cyclin D1 in the HBx-HepG2 cells. Kaemferol at 100 μmol/L also suppressed the protein level of p-GSK-3β and the β-catenin protein levels in both cytoplasm and nucleus. LiCl treatment reversed the inhibitory effect of kaempferol on the growth, invasion and migration of the HBx-HepG2 cells. CONCLUSION: Kaempferol inhibits cell proliferation, invasion and migration via activating Wnt/β-catenin signaling in HBx-HepG2 cells.