Effect of miR-206 over-expression on proliferation and migration of pap?illary thyroid carcinoma K1 cells

AIMTo determine the effect of microRNA-206 (miR-206) on proliferation and migration of human papillary thyroid carcinoma K1 cells and to explore its possible mechanism. METHODSThe expression of miR-206 in the K1 cells was detected by RT-qPCR. The cell viability was detected by CCK-8 assay. The number of viable K1 cells was counted by the method of Trypan blue exclusion. The migration ability of K1 cells was detected by Transwell chamber migration assay. Bioinformatics software was used to predict the target gene of miR-206. The targeting relationship between miR-206 and c-Met was verified by dual-luciferase reporter assay. The protein levels of c-Met, p-Met, AKT, p-AKT, mTOR and p-mTOR were determined by Western blot. RESULTSAfter the K1 cells were transfected with miR-206 mimic transiently, the relative expression of miR-206 in treatment group was significantly higher than that in blank group and negative control group (P<0.01). The results of CCK-8 assay and Trypan blue exclusion assay showed that the proliferation ability of K1 cells in treatment group transfected with miR-206 mimic was significantly inhibited compared with other groups (P<0.01). The results of Transwell assay showed that the number of migratory K1 cells in treatment group was lower than that in blank group and negative control group (P<0.01). Moreover, our results demonstrated that miR-206 directly targeted c-Met and repressed the activation of downstream AKT/mTOR signaling pathway. CONCLUSION miR-206 over-expression inhibits the proliferation and migration abilities of papillary thyroid carcinoma K1 cells, and its mechanism may be related to the inhibition of c-Met/AKT/mTOR signaling pathway.     

MicroRNA-497 inhibits viability,invasion and migration of thyroid papillary cancer cells

AIM:To investigate the underlying mechanisms of mircoRNA-497 (miR-497) inhibiting the viability, migration and invasion of papillary thyroid cancer (PTC) cells. METHODS:TargetScan 6.0 was used to predict the potential targets of miR-497. The target gene was confirmed by luciferase reporter assay, RT-qPCR and Western blot. The expression levels of miR-497 and its target gene in the PTC tissues were detected by RT-qPCR. Gene transfection, MTT assay, and cell migration and invasion assays were used to investigate the effects of miR-497 and its target gene on PTC cell viability, migration and invasion. RESULTS:AKT3 was demonstrated to be the direct target gene of miR-497. In addition, AKT3 expression was higher in the PTC tissues than that in normal tissues (P<0.05) and negatively correlated with miR-497 expression (r=-0.573 7, P<0.01). Furthermore, down-regulation of AKT3 also suppressed cell viability, migration and invasion of PTC, which played similar roles of miR-497 over-expression in PTC cells. CONCLUSION:miR-497 inhibits the viability, migration and invasion of PTC cells by directly targeting AKT3.     

Effects of BCL-3 gene silencing on the proliferation and drug sensitivity of human colorectal cancer cell line RKO with high expression of BCL-3

AIM：To construct lentiviral vectors for RNA interference (RNAi) of BCL-3 gene, and to detect the changes of biological behaviors and drug sensitivity of colorectal cancer cells after BCL-3 gene silencing. METHODS：The expression of BCL-3 in five human colorectal cancer cell lines was detected by RT-PCR and Western blotting. Lentiviral vectors for RNAi of BCL-3 gene were constructed and transfected into the human colorectal cancer cell line with high expression of BCL-3, and then the silencing effect was detected by Western blotting. After BCL-3 gene silencing, the change of cell proliferation was detected by MTT assay and soft agar colony formation assay, and the change of drug sensitivity was detected by MTT assay. RESULTS：BCL-3 was highly expressed in human colorectal cancer cell line RKO. Lentiviral vectors for RNAi of BCL-3 gene were successfully constructed, and Western blotting showed that BCL-3-shRNA2 could efficiently inhibit the expression of BCL-3 protein in RKO cells. After BCL-3 gene silencing, the proliferation ability and colony formation rate of RKO cells were decreased, and the median inhibitory concentration of oxaliplatin for RKO cells also decreased significantly. CONCLUSION: Inhibition of BCL-3 gene expression decreases the proliferation ability of human colorectal cell line RKO with high expression of BCL-3, and enhances the sensitivity of RKO cells to oxaliplatin.     

Construction of lentiviral vector-mediated siRNA knockdown of ER-α36and its action on gastric cancer cell growth

AIM: To construct a lentiviral vector for stable delivery of the ER-α36gene and to detect its effect on SGC7901 cell growth. METHODS: The efficient RNAi targeting sequences identified for the ER-α36gene were screened. The Oligo DNA was synthesized with target sequences and annealed to form double-stranded DNA. Then it was digested by XhoI and EcoR I and connected with GV307 vector to produce LV-ER-α36-RNAi lentiviral vector. PCR was used to screen the positive clones and sequence. The LV-ER-α36-RNAi, pHelper 1.0 and pHelper 2.0 plasmids were co-transfected into 293T cells for producing lentiviral vector and infecting SGC7901 cell line. Fluorescence microscopy, real-time PCR and Western blotting were used to detect the transfection efficiency and gene silencing effect. 17β-estrodial at concentration of 1×10-10 mol/L was used to stimulate the recombinant cell line, and the action on the growth of gastric cancer cells and the expression of Src, ERK1/2 and cyclin D1 were determined. RESULTS: DNA sequencing analysis confirmed the identity of recombinant shRNA expression vectors. Immunofluorescence assay demonstrated that transfection efficiency was above 80%. Transfection of LV-ER-α36-RNAi significantly knocked down the expression of ER-α36 at mRNA and protein levels with tetracycline (TeT) simulating as revealed by real-time PCR and Western blotting. Compared with control group, the growth of the recombinant cell line declined and the expression of Src, ERK1/2 and cyclin D1 and the activation of Src decreased (P<0.05).CONCLUSION: Lentiviral vectors that silenceER-α36expression are constructed successfully and can be used to study the role of ER-α36 in gastric cancer. The ER-α36is related with many kinds of cancer cell growth, including gastric cancer cells.     

Effects of notch1 gene on proliferation and cell cycle of human glioma U251 cells

AIM: To investigate the effect of notch1 gene on the change of proliferation and cell cycle in human glioma U251 cell line. METHODS: The lentiviral vectors, which express notch1 shRNA or notch1 intracellular domain (NICD), were constructed and transfected into U251 cells, respectively. RT-PCR and Western blotting were applied to monitor the validity of down-regulation of notch1 expression and over-expression of NICD. MTT assay was performed to examine the cell proliferation. Flow cytometric analysis was used to detect the cell cycle. RESULTS: The lentiviral vectors, which expressed notch1 shRNA and NICD, were efficient in silencing notch1 expression and over-expression of NICD. Down-regulation of notch1 gene by RNAi inhibited the cell proliferation remarkably (P<0.01), arrested cell cycle at G1 phase (P<0.01) and decreased the cell number of S phase (P<0.01). Over-expression of NICD enhanced the cell proliferation significantly (P<0.01), promoted the cell cycle at G1 phase (P<0.05) and increased the cell number of S phase (P<0.01). CONCLUSION: notch1 gene, which leads to change the proliferation and cell cycle in human glioma U251 cell line, is likely to be potential molecular target for glioma in gene therapy.     

Effects of lentivirus-mediated RWDD3 silencing on proliferation and invasion of human glioma U251 cells

AIM: To investigate the effect of RWDD3 gene silencing on the biological characteristics of human glioma U251 cells.METHODS: A lentiviral vector expressing RWDD3 shRNA was constructed and transfeeted into the U251 cells. The expression of RWDD3 at mRNA and protein levels was detected by real-time PCR and Western blot, respectively. The cell activity was determined by MTT assay. The colony formation ability was detected by the colony formation assay. The cell proliferation ability was detected by BrdU incorporation assay. The cell invasion and migration were evaluated by Transwell assay. Flow cytometry was used to monitor the changes of cell cycle distribution and apoptosis.RESULTS: Recombinant lentivirus was successfully transfected into U251 cells. Compared with the cells transfected with the scrambled shRNA and control cells, the cell activity, colony formation ability, and the invasive and migratory activities were inhibited, the cell cycle was arrested in G₀/G₁ phase, and the apoptosis was increased in the U251 cells transfected with RWDD3 shRNA(P<0.05).CONCLUSION: RWDD3 plays a vital role in proliferation and invasion of glioma cells. It may serve as a potential target of gene therapy for glioma.     

Pantoprazole sodium inhibits epithelial-mesenchymal transition and cisplatin resistance in lung cancer cells and underlying mechanism

AIM: To explore the inhibitory effects of pantoprazole sodium on epithelial-mesenchymal transition and cisplatin resistance in lung cancer cells and the underlying mechanism.METHODS: Using MTT method, wound healing assay, Transwell experiment, Western blot, the differences of morphology, invasion ability, migration ability, drug sensitivity and protein expression between A549/DDP cells and A549 cells were determined. The effect of pantoprazole sodium on morphology, invasion ability, migration ability, drug sensitivity and protein expression in A549/DDP cells were also observed.RESULTS: Compared with A549 cells, A549/DDP cells had higher invasion and migration abilities, and lower drug sensitivity, exhibited mesenchymal phenotype and activated c-Met/AKT/mTOR pathway. Pantoprazole sodium inhibited the abilities of invasion and migration, and reversed the mesenchymal phenotype, drug resistance and the c-Met/AKT/mTOR pathway activation in A549/DDP cells. Treatment with c-Met inhibitor SU11274, PI3K inhibitor LY294002 and mTOR inhibitor rapamycin had the same effects on A549/DDP cells as that of pantoprazole sodium.CONCLUSION: Pantoprazole sodium inhibits invasion, migration, epithelial-mesenchymal transition and cisplatin resistance in lung cancer cells by down-regulating c-Met/AKT/mTOR pathways.     

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.     

Effect of RNAi-mediated IGF1R gene silencing on growth,migration, and invasion of hepatocellular carcinoma cells

AIM: To investigate the effect of RNA interference (RNAi)-mediated insulin-like growth factor 1 receptor (IGF1R) gene silencing on the growth, migration, and invasion of hepatocellular carcinoma cells. METHODS: The most effective siRNA targeting IGF1R gene was designed and screened. After lentiviral expression vector pLVX-shRNA2-IGF1R carrying the most effective siRNA sequence was constructed, it was transfected into 293T cells and packed into pLVX-shRNA2-IGF1R lentivirus. Huh7 and Hep3B cells were infected with the pLVX-shRNA2-IGF1R lentivirus to screen the positive clone Huh7 cells and Hep3B cells with the lentivirus. These Huh7 cells and Hep3B cells were cultured to analyze the mRNA level of IGF1R, cell proliferation, cell cycle, cell apoptosis, cell migration/invasion, and the protein levels of IGF1R, Ki-67, p-AKT, p-ERK1, Gli1, β-catenin, cyclin D1, p21 and BCL-XL. RESULTS: The mRNA expression of IGF1R in Huh7 cells and Hep3B cells with pLVX-shRNA2-IGF1R lentivirus was significantly reduced. The proliferation of these cells was remarkably inhibited, and the number in G₁ phase was increased significantly. The percentages of apoptotic cells were increased markedly, and the number of cell migration/invasion was decreased markedly. The protein levels of IGF1R, Ki-67, p-AKT, p-ERK1, Gli1, β-catenin, cyclin D1, p21 and BCL-XL were decreased significantly compared with the blank control group and negative control group. CONCLUSION: The RNAi-mediated IGF1R gene silencing significantly suppresses the growth and the malignant biological characteristics of Huh7 cells and Hep3B cells, which may be involved in the reduced protein levels of the above genes induced by down-regulation of IGF1R expression.     

IL-6 promotes epithelial-mesenchymal transition,migration and invasion of papillary thyroid carcinoma TPC-1 cells by inducing lncTCF7 expression

AIM:To investigate the effect of interleukin-6 (IL-6) on epithelial-mesenchymal transition (EMT), migration and invasion of papillary thyroid carcinoma TPC-1 cells by inducing the expression of long noncoding RNA lncTCF7. METHODS:The effects of IL-6 on the expression of lncTCF7 in the TPC-1 cells were detected by RT-qPCR after the TPC-1 cells were treated with IL-6 at 0, 5, 10, 20 and 50 μg/L for 24 h or with IL-6 at 50 μg/L for 0, 6, 12 and 24 h. After the TPC-1 cells were treated with IL-6 at 50 μg/L for 24 h, the effect of IL-6 on the protein expression of E-cadherin and vimentin in the TPC-1 cells was detected by Western blot. The TPC-1 cell line with lncTCF7 over-expression was established, and the effects of lncTCF7 over-expression on EMT, migration and invasion of the TPC-1 cells were measured by Western blot and Transwell assay. After knockdown of lncTCF7 expression and exposure to IL-6 at 50 μg/L, the effects of lncTCF7 on EMT, migration and invasion of TPC-1 cells treated with IL-6 were observed. RESULTS:The expression of lncTCF7 in the TPC-1 cells was induced by IL-6 in a dose-and time-dependent manner. The expression of E-cadherin was down-regulated, the expression of vimentin was up-regulated, and the migration and invasion abilities of the TPC-1 cells were enhanced by lncTCF7 over-expression (P<0.05). The expression of E-cadherin was decreased, the expression of vimentin, Snail and Slug was increased, and the migration and invasion abilities of the TPC-1 cells and intercellular space were enhanced by IL-6. The above changes induced by IL-6 were significantly inhibited by knockdown of lncTCF7 expression. CONCLUSION:IL-6 promotes the EMT, migration and invasion of papillary thyroid carcinoma TPC-1 cells by inducing the expression of lncTCF7.     

Imperatorin increased sensitivity of lung cancer CD133+ cell subsets to gefitinib by down-regulating c-met expression

AIM: To investigate the role of imperatorin in reversing the resistance of the PC9 CD133⁺ cell subsets to gefitinib. METHODS: MTT assay was performed to evaluate the viability of PC9 cells treated with imperatorin and gefitinib. The expression of c-met, activation of caspases and phosphorylation of epidermal growth factor receptor (EGFR), PI3K and AKT in the PC9 cells treated with imperatorin and gefitinib were determined by Western blot. The percentage of CD133⁺ cell subsets population and the apoptotic rate of the PC9 cells treated with imperatorin and gefitinib were analyzed by flow cytometry. RESULTS: The sensitivity of the PC9 CD133⁺ cell subsets to gefitinib was significantly lower than that of the PC9 CD133^- cell subsets. Treatment with gefitinib alone significantly inhibited the protein levels of EGFR/PI3K/AKT in the PC9 CD133^- cell subsets but not the PC9 CD133⁺ cell subsets. Treatment with gefitinib alone increased the percentage of CD133⁺ cell subsets population in the PC9 cells. However, combination of gefitinib with imperatorin significantly inhibited the enrichment of CD133⁺ cell subsets population. Imperatorin down-regulated c-met expression, suggesting the c-met was the target of imperatorin in the PC9 CD133⁺ cell subsets. The results of MTT assay, Western blot analysis and flow cytometry indicated that imperatorin increased the gefitinib induced inhibition of PI3K/AKT protein levels by down-regulating the expression of c-met, which subsequently induced the cleavage of caspases and apoptosis in the PC9 CD133⁺ cell subsets.CONCLUSION: Imperatorin increases the sensitivity of lung cancer CD133⁺ cell subsets to gefitinib by down-regulating the expression of c-met, and the synergistic anti-tumor effect exists between imperatorin and gefitinib.     

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 axitinib on biological behavior of adrenocortical carcinoma cell line SW-13

AIM: To investigate the effects of axitinib on the biological behavior of adrenocortical carcinoma cell line SW-13. METHODS: CCK-8 assay was used to measured the viability of SW-13 cells treated with axitinib at different concentrations. The cell cycle distribution was analyzed by flow cytometry. The apoptotic rate was also analyzed by flow cytometry with Annexin V/PI double staining. Wound healing experiment and Transwell invasion assay were used to observe cell migration and invasion abilities,respectively. The protein levels of vascular endothelial growth factor receptor 2(VEGFR2), extracellular regulated protein kinases 1/2 (ERK1/2) and p-ERK1/2 were determined by Western blot. RESULTS: After treated with axitinib, the viability of SW-13 cells was significantly inhibited, the cell cycle was blocked in G₂/M phase, and the apoptosis rate was increased. The migration and invasion abilities of SW-13 cells were markedly inhibited by axitinib (P<0.01). The protein levels of VEGFR2 and p-ERK1/2 in the SW-13 cells were significantly decreased with axitinib treatment (P<0.01). CONCLUSION: Axitinib inhibits the viability, blocks the cell cycle, promotes cell apoptosis, and inhibits the migration and invasion abilities of SW-13 cells. The mechanism may be related to inhibition of VEGFR2 expression and reduction of ERK1/2 phosphorylation.     

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.     

Inhibitory effect of anti-miR-196a on invasion and migration of human pancreatic cancer PANC-1 cells

AIM:To investigate the expression of miR-196a in different pancreatic cancer cell lines and to observe the effect of anti-miR-196a on the biological behaviors of human pancreatic cancer PANC-1 cells. METHODS:The expression of miR-196a in the pancreatic cancer cells was examined by real-time quantitative PCR. Anti-miR-196a was chemically synthesized and transfected into PANC-1 cells by Lipofectamine 2000. The cell proliferation was measured by CCK-8 assay. The apoptosis was determined by flow cytometry. Matrigel invasion assay was performed to examine the migration and invasion of the tumor cells. The wild-type and mutant-type NF-κB inhibitor α(NFKBIA) 3'UTR luciferase reporter vectors were constructed. The relative activity of Renilla luciferase was detected to confirm the binding site of miR-196a on NFKBIA mRNA. RESULTS:The expression of miR-196a in human pancreatic cancer cell lines was significantly higher than that in human pancreatic ductal epithelial H6c7 cells. The expression of anti-miR-196a in miR-196a group was down-regulated. After transfected with miR-196a, no change of cell proliferation and apoptosis was observed, but the abilities of invasion and migration were reduced(P<0.01). Compared with negative control, wild-type NFKBIA3'UTR or mutant-type NFKBIA 3'UTR, cotransfection of anti-miR-196a and wild-type NFKBIA 3'UTR significantly increased the relative activity of Renilla luciferase. CONCLUSION:miR-196a is one of the oncomiRs and may be a target microRNA of human pancreatic cancer for gene therapy.     

The expression and significance of Apaf-1 in papillary thyroid carcinoma

AIM: To investigate the mRNA and protein expression of apoptotic protease-activating factor 1 (Apaf-1) in papillary thyroid carcinoma (PTC) and its relationship with cell proliferation.METHODS: The methods of real-time PCR, Western blot and immunohistochemistry were used to detect the mRNA and protein expression of Apaf-1 in PTC and tumor-adjacent tissues. The relationship between Apaf-1 expression and clinicopathological characteristics was analyzed. The effect of Apaf-1 on cell proliferation was verified by down-regulating the expression of Apaf-1 in CGTHW-3 cells.RESULTS: The mRNA and protein expression levels of Apaf-1 in the PTC tissue were significantly lower than those in the tumor-adjacent tissue (P<0.05). Down-regulation of Apaf-1 expression enhanced the proliferation of CGTHW-3 cells (P<0.05).CONCLUSION: The expression of Apaf-1 is low in PTC, and inhibition of its expression enhances the proliferation of CGTHW-3 cells. Apaf-1 may play a tumor suppressor role in PTC.     

Construction of a lentiviral RNA interference vector targeting rat myocardin and its effect on vascular smooth muscle cell differentiation

AIM: To construct a lentiviral RNA interference(RNAi)vector targeting rat myocardin mRNA and to investigate its effect on the differentiation of vascular smooth muscle cells(VSMCs).METHODS: Three pairs of dsDNA targeting rat myocardin mRNA were designed, synthesized and cloned into lentiviral vector pGCSIL-GFP to generate pGCSIL-GFP-shMyocd lentvirus. A Flag-tagged myocardin-overexpression vector pEGFP-N1-Myocd was constructed with pEGFP-N1/X124G. After these two vectors were cotransfected into 293T cells, the flag protein was assessed by Western blotting to analyze the knockdown effect of pGCSIL-GFP-shMyocd. The expression of myocardin and SM22α was also detected by RT-PCR and Western blotting after the pGCSIL-GFP-shMyocd viruses were transfected into primary cultured rat aortal VSMCs.RESULTS: The rat myocardin lentviral RNAi vector pGCSIL-GFP-shMyocd and myocardin-overexpression vector pEGFP-N1-Myocd were successfully constructed. After these two kinds of vectors were cotransfected into 293T cells,the No.1 interfering vector displayed the highest inhibitory effect on flag expression.After the No.1 lentvirus at the titer of 1×10¹² TU/L was transfected into VSMCs, the myocardin and SM22α expression was significantly attenuated. CONCLUSION: The lentiviral pGCSIL-GFP-shMyocd RNAi vector is successfully constructed, which is useful for further study regarding the molecular mechanism of the phenotypic switching in VSMCs under special pathological conditions such as atherosclerosis. Inhibition of myocardin expression in VSMCs leads to the decrease in the expression of differentiation marker, and implies a crucial role of myocardin in VSMCs differentiation.     

Significance of TRPM8 protein expression in lung adenocarcinoma

AIM To investigate the significance of transient receptor potential cation channel subfamily M member 8 （TRPM8） protein expression in lung adenocarcinoma. METHODS The tumor samples from 112 cases of patients with lung adenocarcinoma were collected in our hospital, and 4~5 years of follow-up was conducted. The protein expression of TRPM8 was analyzed by immunohistochemical staining, and the correlations between the TRPM8 protein expression and the clinical characteristics including prognosis of the patients with lung adenocarcinoma were investigated. After TRPM8 protein expression was up-regulated in A549 lung adenocarcinoma cells by lentiviral infection, the proliferation of A549 cells was analyzed by CCK-8 assay and colony formation assay, the cell cycle and apoptosis were analyzed by flow cytometry, and the migration and invasion abilities of the cells were measured by scratch experiment and Transwell assay. The TRPM8 protein expression was stably up-regulated in H1299 cells by lentiviral infection, and then the left and right buttocks of the immunodeficient mice were subcutaneously injected with empty vector control cells and TRPM8-overexpressing cells, respectively. The effects of TRPM8 on the growth of H1299 cell-derived xenograft tumor in immunodeficient mice were evaluated. RESULTS The 4~5-year survival rate in the patients with high TRPM8 protein expression was significantly higher than that in the patients with low expression of TRPM8 protein （P=0.017）. The tumor maximum diameter in the patients with high TRPM8 protein expression was significantly smaller than that in the patients with low TRPM8 protein expression （P=0.028）. The viability, the number of colonies and the migration and invasion abilities of TRPM8-overexpressing A549 cells were significantly decreased as compared with empty vector and parental cells （P<0.01）. The results of flow cytometry analysis showed that the proportion of A549 cells at S stage was significantly increased in TRPM8 overexpression group as compared with empty vector group （P<0.01）. The growth rate and the weight of TRPM8-overexpressing H1299 cell-derived xenograft tumor in immunodeficient mice were significantly lower than those in empty vector group （P<0.01）. CONCLUSION TPRM8 is a tumor suppressor in lung adenocarcinoma, and low expression of TRPM8 protein was a poor prognositic indicator of patients with lung adenocarcinoma.     

Notch1 regulates stemness and chemotherapeutic sensitivity of human glioma U251 cells

AIM: To investigate whether Notch1 changes stemness and chemotherapeutic sensitivity in human glioma U251 cells. METHODS: The lentiviral vectors, which expressed Notch1-shRNA or Notch1 intracellular domain (NICD), were transfected into U251 cells. Western blot and immunofluorescence staining were applied to monitor the validity of the cells, down-regulation of Notch1 expression or over-expression of NICD. The proportion of CD133⁺ cells was analyzed by flow cytometry. The expression of nestin and GFAP was identified by immunofluorescence staining. The formation rate of tumor cell spheres and the implanted tumor growth in SCID mice were observed. MTT assay was performed to evaluate the chemotherapeutic sensitivity to VM-26 and BCNU of the cells with different treatments. RESULTS: Stemness was significantly enhanced in the cells over-expressing NICD. For example, the proportion of CD133⁺ cells was increased, the expression of nestin was up-regulated, the expression of GFAP was down-regulated, and the formation rate of tumor cell spheres and implanted tumor growth were increased. The chemotherapeutic sensitivity to VM-26 and BCNU of the cells was decreased. In the cells with Notch1 gene down-regulation by RNAi, the stemness was inhibited and chemotherapeutic sensitivity was increased. CONCLUSION: Notch1, which leads to the change of stemness and chemotherapeutic sensitivity in human glioma U251 cells, is likely to be a potential molecular target for treatment of glioma.