人参皂苷Rg3 通过PI3K/AKT 信号系统调控CaM 基因表达促进胃癌BGC-823 细胞的凋亡

[摘要] 目的：探讨人参皂甙Rg3 通过PI3K/AKT信号通路干扰CaM基因的表达及对胃癌BGC-823 细胞凋亡的影响。方法:胃癌BGC-823 细胞的培养与传代完成后,Western blotting 检测胰岛素样生长因子-1 (insulin-like growth factor-1,IGF-1)和/或Rg3分别作用胃癌BGC-823 细胞后p-AKT和CaM 蛋白表达水平,MTT法检测IGF-1 和/或Rg3 对胃癌BGC-823 细胞增殖的影响,Transwell 法检测IGF-1 和/或Rg3 对胃癌BGC-823 细胞侵袭的影响,流式细胞术检测IGF-1 和/或Rg3 对胃癌BGC-823 细胞凋亡的影响。结果：随着IGF-1 作用时间延长,胃癌BGC-823 细胞中p-AKT蛋白和CaM蛋白的表达水平均明显提高（均P<0.05）;与空白对照组比较,Rg3 组明显抑制胃癌BGC-823 细胞增殖,而IGF-1 组和IGF-1+Rg3 组明显促进胃癌BGC-823 细胞增殖（均P<0.05）;与空白对照组比较,Rg3 组明显降低胃癌BGC-823 细胞侵袭,而IGF-1 组和IGF-1+Rg3 组明显促进胃癌BGC-823 细胞侵袭能力（均P<0.05）;流式细胞术检测显示,与空白对照组比较,Rg3 组明显促进胃癌BGC-823 细胞凋亡,而IGF-1 组和IGF-1+Rg3 组明显抑制胃癌BGC-823 细胞凋亡（均P<0.05）。结论:人参皂甙Rg3 通过阻断PI3K/AKT信号通路来抑制CaM的表达,进而促进胃癌BGC-823细胞的凋亡。     

BCG (bacille Calmette-Guérin)-activated lymphocytes (BAK cells) induce apoptosis in urinary bladder carcinoma cell line T24 in vitro

Background. We previously reported the basic characteristics of BCG (bacille Calmette-Guérin)-activated killer (BAK) cells, which exhibited antitumor effects against the bladder cancer cell line T24. Our study suggested that both BCG and BAK cells were responsible for the inhibition of tumor cell proliferation; however, the basic mechanism of BCG or BAK cells in this inhibition was not clear. We here report the antitumor effects of BAK cells, which correlated with the induction of apoptosis in T24 cells. Methods. Lymphocytes were cultured with BCG to examine ³H-thymidine uptake, and the subpopulation was evaluated by immunocytometry. T24 cells were then cultured with BAK cells for the analysis of ³H-thymidine uptake and apoptosis induction by DNA electrophoresis; pathology study, and cell-cycle analysis were also done. Culture supernatants of BAK and T24 cells were also investigated to detect interferon-γ (IFN-γ), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α). Results. The ³H-thymidine uptake study of lymphocytes showed that BCG activated the lymphocytes. Evaluation by immunocytometry revealed that CD4⁺ and CD8⁺ T cells were induced by BCG. The ³H-thymidine uptake study of T24 cells revealed that BAK cells inhibited tumor cell proliferation. DNA electrophoresis, the morphological study, and cell-cycle analysis by immunocytometry demonstrated that apoptosis in T24 cells was induced when they were cultured with BAK cells. IFN-γ, IL-6, and TNF-α were detected in the culture supernatants of BAK and T24 cells. Conclusions. Cytokine production and the induction of apoptosis may, together, be the major mechanisms of the antitumor action seen when BAK cells were employed against T24 cells; BAK cells could be employed as clinical effectors against bladder cancer. Received: January 7, 2000 / Accepted: April 27, 2000     

Antisense oligonucleotide targeting Livin induces apoptosis of human bladder cancer cell via a mechanism involving caspase 3

Background and Aim

in recent years, Livin, a new member of IAPs family, is found to be a key molecule in cancers. Researchers consider Livin may become a new target for tumor therapy; however, the role of it in bladder cancer is still unclear. The purpose of this article is to investigate Antisense Oligonucleotide (ASODN) of Livin on treating bladder cancer cell and underlying mechanisms.

Methods

Phosphorathioate modifying was used to synthesize antisense oligonucleotides targeting Livin, followed by transfection into human bladder cancer cell 5637. After transfection, Livin mRNA and protein level, cell proliferation and apoptosis changes, caspase3 level and its effect on human bladder cancer transplantable tumor in nude mice were measured.

Result

results showed Livin ASODN effectively inhibited Livin expression and tumor cell proliferation, and these effects probably through enhanced caspase3 activity and apoptosis of tumor cells. In nude mice transplantable tumor model, Livin expressions were inhibited meanwhile caspase3 expression was increased. Tumor growth slowed down and apoptosis was enhanced.

Conclusion

Our data suggest that Livin plays an important role in inhibiting apoptosis of bladder cancer cells. Livin ASODN may promote cell apoptosis, inhibit bladder cancer growth, and become one of the methods of gene therapy for bladder cancer.     

Effect of sirolimus on urinary bladder cancer T24 cell line

Background

Sirolimus is recently reported to have antitumour effects on a large variety of cancers. The present study was performed to investigate sirolimus''s ability to inhibit growth in T24 bladder cancer cells.

Methods

T24 bladder cancer cells were treated with various concentrations of sirolimus. MTT assay was used to evaluate the proliferation inhibitory effect on T24 cell line. The viability of T24 cell line was determined by Trypan blue exclusion analysis.

Results

Sirolimus inhibits the growth of bladder carcinoma cells and decreases their viability. Significant correlations were found between cell proliferation and sirolimus concentration (r = 0.830; p < 0.01) as well as between cell viability and sirolimus concentration (r = -0.896; p < 0.01).

Conclusion

Sirolimus has an anti-proliferation effect on the T24 bladder carcinoma cell line. The information from our results is useful for a better understanding sirolimus''s anti-proliferative activity in the T24 bladder cancer cell line.     

人参皂苷Rg3通过人乳腺珠蛋白A促进乳腺癌MDA MB 231细胞凋亡及其可能的机制

目的:研究人参皂苷Rg3通过促进乳腺癌MDA-MB-231细胞人乳腺珠蛋白A(mammaglobin-A,MGBA)的表达从而抑制细胞增殖的作用机制.方法:MTT法和流式细胞术检测5、10、15 μg/ml Rg3对乳腺癌细胞增殖和凋亡的影响,Westernblotting检测对乳腺癌细胞内MGBA表达的影响;Rg3和siRNA-MGBA单独或联合处理MDA-MB-231细胞,MTT法和流式细胞术检测其对细胞增殖和凋亡的影响,Western blotting检测其对细胞MGBA表达的影响,敏感硫电极法检测其对乳腺癌MDA-MB-231细胞H2S分泌的影响.结果:作用细胞48 h后,与对照组相比,5、10、15 μg/ml Rg3组MDA-MB-231细胞增殖抑制率明显增高[(18.78±0.82)％、(33.25±1.17)％、(35.11±0.94)％vs(9.72±0.91)％,均P＜0.05],Rg3可促进MDA-MB-231细胞的凋亡(P＜0.05),也明显增强MDA-MB-231细胞内MGBA蛋白的表达(P＜0.05).与对照组相比,Rg3组MDA-MB-231细胞增殖抑制率明显升高[(30.12±1.01)％ vs(10.66 ±0.59)％,P＜0.05],Rg3+ siRNA-MGBA组和siRNA-MGBA组MDA-MB-231细胞增殖抑制率明显降低[(6.61±0.63)％、(7.02±0.46)％ vs (10.66±0.59)％,均P＜0.05];Rg3组MGBA和胱硫醚-γ-裂解酶(cystathionine-γ-lyase,CSE)的表达和H2S的分泌明显增强,而Rg3+ siRNA-MGBA组、siRNA-MGBA组明显抑制(均P ＜0.05).结论:Rg3可以明显抑制乳腺癌MDA-MB-231细胞的增殖,并促进凋亡,其作用机制可能是通过增强MGBA蛋白的表达并激活H2S/CSE系统得以实现的.     

Overexpression of Pim-1 in bladder cancer

Background

Pim-1 is a serine-threonine kinase which promotes early transformation, cell proliferation and cell survival during tumorigenesis. Several studies have demonstrated that Pim-1 kinase play a role in different cancer types, however, the function of Pim-1 in bladder cancer is poorly understood.

Methods

Expression and localization of Pim-1 in human normal and malignant bladder specimens were examined by Immunohistochemistry and Pim-1 staining score was compared with several clinicopathologic parameters. To further demonstrate the biological function of Pim-1 in bladder cancer, its expression was validated in five bladder cancer cell lines by western blot and immunohistochemistry analyses. Subsequent knockdown of Pim-1 was achieved by lentivirus encoding small interfering RNA, and the effect of Pim-1 on bladder cell survival and drug sensitivity were further assessed by colony formation and cell proliferation assays.

Results

When compared with normal epithelium, Pim-1 was overexpressed in bladder cancer epithelium, and the expression level was higher in invasive bladder cancer than Non-invasive bladder cancer specimens. Pim-1 was also detected in all the bladder cancer cell lines examined in our study. Moreover, the knockdown of Pim-1 significantly inhibited bladder cancer cell growth and also sensitized cells to chemotherapeutic drugs in vitro.

Conclusions

Our results in this study suggest that Pim-1 may play a role in bladder cancer initiation and progression. Since Pim-1 is also involved in bladder cancer cell survival and drug resistance, Pim-1 is a potential candidate for targeted therapy in bladder cancer.     

MicroRNA-320c inhibits tumorous behaviors of bladder cancer by targeting Cyclin-dependent kinase 6

Background

Increasing evidence has suggested that dysregulation of microRNAs (miRNAs) could contribute to human disease including cancer. Previous miRNA microarray analysis illustrated that miR-320c is down-regulated in various cancers. However, the roles of miR-320c in human bladder cancer have not been well elucidated. Therefore, this study was performed to investigate the biological functions and molecular mechanisms of miR-320c in human bladder cancer cell lines, discussing whether it could be a therapeutic biomarker of bladder cancer in the future.

Methods

Two human bladder cancer cell lines and samples from thirteen patients with bladder cancer were analyzed for the expression of miR-320c by quantitative RT-PCR. Over-expression of miR-320c was established by transfecting mimics into T24 and UM-UC-3. Cell proliferation and cell cycle were assessed by cell viability assay, flow cytometry and colony formation assay. Cell motility ability was evaluated by transwell assay. The target gene of miR-320c was determined by luciferase assay, quantitative RT-PCR and western blot. The regulation of cell cycle and mobility by miR-320c was analyzed by western blot.

Results

We observed that miR-320c was down-regulated in human bladder cancer tissues and bladder cancer cell lines T24 and UM-UC-3. Over-expression of miR-320c could induce G1 phase arrest in UM-UC-3 and T24 cells, and subsequently inhibited cell growth. We also indentified miR-320c could impair UM-UC-3 and T24 cell motility. In addition, we identified CDK6, a cell cycle regulator, as a novel target of miR-320c. Moreover, we demonstrated miR-320c could induce bladder cancer cell cycle arrest and mobility via regulating CDK6. We also observed that inhibition of miR-320c or restoration of CDK6 in miR-320c-over-expressed bladder cancer cells partly reversed the suppressive effects of miR-320c.

Conclusions

miR-320c could inhibit the proliferation, migration and invasion of bladder cancer cells via regulating CDK6. Our study revealed that miR-320c could be a therapeutic biomarker of bladder cancer in the future.     

半乳糖凝集素3 在膀胱癌组织中表达和临床意义及其对T24 细胞恶性生物学行为的影响

[摘要] 目的：探讨半乳糖凝集素3（galectin-3）在膀胱癌组织中的表达与患者临床病理特征的关系及其对膀胱癌T24 细胞增殖、侵袭和凋亡的影响。方法：收集2014 年5 月至2016 年6 月在川北医学院附属医院收治的、经病理切片确诊的104 例膀胱癌患者的癌和癌旁组织标本，用免疫组织化学法检测膀胱癌和癌旁组织中半乳糖凝集素3 蛋白的表达，分析其表达与患者临床病理特征的相关性。将siRNA-Gal3、siRNA-Control 分别转染至T24 细胞，用Weatern blotting 检测细胞的半乳糖凝集素3 蛋白表达水平，MTT法检测细胞的增殖，Transwell 实验检测细胞的侵袭，流式细胞术检测细胞的凋亡。结果：膀胱癌组织中半乳糖凝集素3 阳性表达率显著高于癌旁组织（73.1% vs 9.6%，P<0.05），膀胱癌组织中半乳糖凝集素3 的表达与组织学分级、肿瘤的浸润深度、淋巴结转移和TNM分期均有关（均P<0.05），与性别和年龄无关（P>0.05）。siRNA-Gal3 显著下调半乳糖凝集素3 蛋白的表达水平（P<0.05），干扰半乳糖凝集素3 表达后：T24 细胞的增殖能力和侵袭能力均明显降低（均P<0.05）；细胞的凋亡率明显增加（P<0.05）。结论：半乳糖凝集素3 在膀胱癌组织中呈高表达，并与膀胱癌患者临床病理特征存在密切关系。干扰半乳糖凝集素3 蛋白的表达可抑制膀胱癌T24 细胞的增殖与侵袭，促进细胞的凋亡。     

LncRNA-CASC7 inhibits the proliferation and migration of colon cancer by negatively regulating the PI3K/Akt signaling pathway

BackgroundThis study aims to investigate the effect of LncRNA-CASC7 (cancer susceptibility candidate 7) on the proliferation and migration of colon cancer cells and its possible mechanism.MethodsIn this study, quantitative real-time polymerase chain reaction (qRT-PCR) was employed for the detection of lncRNA-CASC7 expression in 54 colon cancer tissues and 5 colon cancer cell lines. This study aimed to evaluate the significant correlation between the lncRNA-CASC7 expression, the clinical features, and the survival rate of patients. LncRNA-CASC7 was overexpressed by lipofectin transfection. Cell proliferation was detected by the methyl thiazolyl tetrazolium (MTT) assay. Transwell assay was conducted to examine cell migration and invasion. The target gene was verified by dual fluorescein. The expression of proliferation and invasion-related proteins was detected via western blotting (WB).ResultsThe LncRNA-CASC7 expression in colon cancer was considerably decreased than in nearby healthy tissues (P<0.01). Its expression level was linked to survival rate, lymph node metastasis, and tumor node metastasis (TNM) stage. Similarly, the expression of lncRNA-CASC7 was decreased in 5 colon cancer cell lines. The proliferative, invasive, and migratory potential of cells was considerably decreased by lncRNA-CASC7 overexpression. Overexpression of lncRNA-CASC7 significantly inhibited the expression of proteins Ki-67 and PNCA (associated with proliferation) and proteins N-cadherin, E-cadherin, and vimentin (linked with metastasis). Further studies showed that overexpression of LncRNA-CASC7 could significantly inhibit the PI3K/Akt signaling pathway in colon cancer cells.ConclusionsThe PI3K/Akt signaling cascade is negatively regulated by LncRNA-CASC7, which serves as a tumor suppressor gene by attenuating colon cancer cell proliferation, invasion, and migration, thus affecting the tumor progression and prognosis of colon cancer patients.     

人参皂苷Rg3对人类乳腺癌MCF-7细胞Cx26基因表达及细胞间隙连接通讯功能的影响

目的研究人参皂苷Rg3对人类乳腺癌细胞MCF-7增殖抑制作用、连接蛋白cx26基因表达及对细胞间隙连接通讯（GJIC）功能的影响。方法使用含不同浓度人参皂苷Rg3培养基体外培养MCF-7细胞24h,并设正常培养条件下MCF-7细胞为对照组,采用四甲基偶氮唑蓝（MTF）法检测人参皂苷Rg3各浓度下MCF-7细胞增殖活力,并选取能明显抑制MCF．7细胞增殖的人参皂苷Rg3浓度组为实验组。RT—PCR检测各实验组和对照组连接蛋白Cx26 mRNA的表达。通过划痕标记荧光传输实验检测上述各组MCF,7细胞GJIC功能的恢复情况。结果在含人参皂苷Rg310、20、40、80、160斗g／ml体外培养MCF-7细胞24h后,MCF-7细胞增殖的抑制率分别为3．1％、5．2％、16．0％、26.3％、29．1％。与对照组比较,质量浓度在40μg／ml以上的人参皂苷Rg3均可明显抑制肿瘤细胞增殖（P〈0．05）,故选取含40、80、160斗g／m1人参皂苷Rg3MCF-7细胞组为实验组。在各实验组中,随人参皂苷Rg3质量浓度的增大,Cx26 mRNA表达逐渐增强,与对照组相比,差异有统计学意义（P〈0．05）。荧光黄染料划痕标记荧光传输实验显示,对照组荧光黄染料荧光染色仅限于单个细胞,各实验组荧光黄染料荧光可通过细胞间隙连接传输至相邻细胞,形成片状荧光染色。结论一定浓度人参皂苷Rg3可增强人类乳腺癌细胞MCF-7 Cx26基因表达,恢复其GJIc功能,这可能是人参皂苷Rg3抑制MCF-7细胞增殖,发挥抗肿瘤作用机制之一。     

SOX10 is over-expressed in bladder cancer and contributes to the malignant bladder cancer cell behaviors

Purpose

To detect the expression level and significance of SOX10 in human bladder cancer.

Methods

Immunohistochemical analyses were performed to assess SOX10 protein level using a bladder cancer tissue microarray (including 59 spots of cancer tissues and 46 spots of paired normal tissues) and 31 specimens and to define the relationship between SOX10 and clinicopathological bladder cancer characteristics in patients. SOX10 protein and mRNA levels in bladder cancer cell lines (T24, 5637, BIU87, EJ) and transitional cell papilloma cell line (RT4) were tested by western blotting and quantitative real-time PCR (q-PCR), respectively. Cell Counting Kit-8 (CCK-8) and colony formation assays were performed to investigate bladder cancer cell proliferation after SOX10 knockdown. The effect of SOX10 on cell migration and invasion was analyzed by Transwell and Matrigel assays. Kaplan–Meier survival curves and Cox regression analyses were used to evaluate SOX10 prognostic significance for bladder cancer patients. The mechanisms by which SOX10 promote bladder cancer progression were examined by western blotting.

Results

SOX10 protein was upregulated in 74.4% of bladder cancer tissues compared with adjacent normal tissues (32.6%). SOX10 protein was also upregulated in malignant cell lines. In addition, high SOX10 expression was related with clinical stage (P = 0.008), T stage (P = 0.004), histological grade (P = 0.002) and lymph node metastasis (P = 0.006). Kaplan–Meier survival curves and Cox regression analyses showed that SOX10 functioned as an independent prognostic factor for overall survival. SOX10 knockdown in bladder cancer cells significantly impacted proliferation, migration and invasion, and SOX10 might promote bladder cancer progression by altering β-catenin and Met expression.

Conclusion

SOX10 was over-expressed in bladder cancer and promoted malignant bladder cancer cell behaviors. SOX10 has potential as a molecular target for bladder cancer treatment.

     

BCG effects on telomerase activity in bladder cancer cell lines

Background. Although intravesical bacillus Calmette-Guerin (BCG) therapy is very effective in the treatment of and prophylaxis against superficial bladder cancer, its exact mechanism of action is not clear. In this study, the effect of BCG on telomerase activity was examined in the T24 and J82 bladder cancer cell lines, the ACHN human renal cell carcinoma cell line, and the PC-3 human prostate cancer cell line. Methods. T24 and J82 cells were cocultured with BCG for 5 days. Telomerase activity was measured by telomeric repeat amplification protocol. Cell-cycle phase was determined by FACS analysis. Results. Telomerase activity in all cell lines provided high absorbance. Telomerase activity in BCG-treated T24 and J82 cells was significantly decreased when compared with that in the nontreated cells. On the other hand, telomerase activity did not change in ACHN and PC-3 cells after they had been cocultured with BCG. In BCG-treated T24 cells and J82 cells, apoptotic cells were markedly increased compared with those in the nontreated cells. Conclusion. These results suggest that the reduction of telomerase activity is related to the mechanism of BCG effects. Possible mechanisms to be considered are either that BCG inhibits telomerase first, or that it induces apoptosis and decreases telomerase activity as a result of this induction. Received: May 25, 2001 / Accepted: February 21, 2002     

miR-144-3p靶向调控E2F3抑制膀胱癌T24细胞的增殖与侵袭

目的:探讨miR144-3p在膀胱癌组织及细胞中的表达及其对T24细胞增殖与侵袭的影响.方法:选用2018年2月至2018年12月空军军医大学唐都医院手术切除的36例膀胱癌组织及10例正常膀胱上皮组织标本,以及人膀胱癌细胞株T24和正常尿路上皮细胞株SV-HUC-1,用qPCR法检测膀胱癌组织和细胞中miR144-3p...     

AG490 在膀胱癌中的抗癌效应及其机制

 目的 观察JAK2激酶抑制剂AG490对膀胱癌细胞增殖和凋亡的影响，并探讨其抗癌机制。方法 应用不同剂量AG490处理膀胱癌细胞系BIU-87，台盼蓝排斥试验检测细胞活力，噻唑蓝比色试验检测细胞增殖，克隆形成试验进一步检测膀胱癌细胞系干细胞对药物的敏感性，Hoechst33258／PI荧光双染检测细胞凋亡特征，流式细胞仪检测细胞周期和凋亡，Western blot检测州AK2、STAT3、p-STAT3、Cyclin D1、bcl—xL蛋白表达水平；并建立膀胱癌荷瘤模型，观察AG490体内抗肿瘤作用。结果 AG490明显抑制膀胱癌细胞增殖和干细胞克隆形成，使细胞周期阻滞，促进膀胱癌细胞凋亡；并可使p-JAK2、STAT3、p-STAT3、Cyclin D1、bcl-xL蛋白表达水平明显下降。裸鼠移植瘤在AG490的作用下明显缩小。结论 AG490通过阻断STAT3信号通路，抑制膀胱癌细胞的增殖，促进其调亡。     

Bladder cancer cell lines adapt their aggressiveness profile to oxygen tension

During the process of tumor growth, cancer cells will be subjected to intermittent hypoxia. This results from the delay in the development of the vascular network in relation to the proliferation of cancer cells. The hypoxic nature of a tumor has been demonstrated as a negative factor for patient survival. To evaluate the impact of hypoxia on the survival and migration properties of low and high-grade bladder cancer cell lines, two low-grade (MGHU-3 and SW-780) and two high-grade (SW-1710 and T24) bladder cancer cell lines were cultured in normoxic (20% O₂) or hypoxic atmospheric conditions (2% O₂). The response of bladder cancer cell lines to hypoxic atmospheric cell culture conditions was examined under several parameters, including epithelial-mesenchymal transition, doubling time and metabolic activities, thrombospondin-1 expression, whole Matrix Metallo-Proteinase activity, migration and resistance to oxidative stress. The low-grade cell line response to hypoxia was heterogeneous even if it tended to adopt a more aggressive profile. Hypoxia enhanced migration and pro-survival properties of MGHU-3 cells, whereas these features were reduced for the SW-780 cell line cultured under low oxygen tension. The responses of tested high-grade cell lines were more homogeneous and tended to adopt a less aggressive profile. Hypoxia drastically changed some of the bladder cancer cell line properties, for example matrix metalloproteinases expression for all cancer cells but also switch in glycolytic metabolism of low grade cancer cells. Overall, studying bladder cancer cells in hypoxic environments are relevant for the translation from in vitro findings to in vivo context.     

人参皂苷Rg3对鼻咽癌肿瘤干细胞放疗增敏的作用研究

目的探讨人参皂苷Rg3对体外培养鼻咽癌肿瘤干细胞放疗敏感性的影响。方法采常规无血清悬浮培养法从鼻咽癌低分化细胞株CNE-2中筛选出鼻咽癌肿瘤干细胞样细胞亚群CNE-2S;采随机分组法将细胞分为人参皂苷Rg3组(15μg/m L)、放疗组和人参皂苷Rg3(15μg/m L)联合放疗组;人参皂苷Rg3干预4 h后,将三组细胞16 Gy放射线照射30 min,然后在培养箱内继续孵育1 d、2 d和3 d,再进行相关测定。MTT法检测各组CNE-2S细胞增殖抑制率;DAPI染色法检测各组CNE-2S细胞凋亡情况,并分析细胞的光密度和面密度变化;Elisa法检测各组CNE-2S细胞SOD水平。结果 1 d、2 d和3 d,人参皂苷Rg3联合放疗组的细胞增殖抑制率以及细胞SOD水平均明显高于人参皂苷Rg3组和放疗组,而细胞光密度、面密度明显于人参皂苷Rg3和放疗组,比较差异均有统计学意义(P<0.01)。结论人参皂苷Rg3可显著提高CNE-2S细胞的放疗敏感性,其促进细胞SOD表达可能是其作用机制之一。     

miR-19a acts as an oncogenic microRNA and is up-regulated in bladder cancer

Background

The application of microRNAs (miRNAs) as potential biomarkers and therapy targets has been widely investigated in many kinds of cancers. The discovery of tumor associated miRNAs in serum of patients supported the use of plasma/serum miRNAs as noninvasive means of cancer detection. However, the aberrant expression of miRNAs in bladder cancer patients and their intensive roles and mechanisms in bladder cancer are poorly understood.

Methods

Taqman probe stem-loop real-time PCR was used to accurately measure the levels of miR-19a in bladder cancer cell lines, 100 pairs of bladder cancer tissues and the adjacent non-neoplastic tissues and also the plasma collected from bladder cancer patients and normal controls. miR-19a mimics and inhibitors were transfected into bladder cancer cells to investigate its role on regulating cell proliferation which was measured by CCK-8 and colony formation assay. The target of miR-19a was identified by western blot and whether its regulatory role depends on its target was improved by a rescue experiment with miR-19a mimic and PTEN expression plasmid.

Results

miR-19a was significantly up-regulated in bladder cancer tissues and high-level of miR-19a was correlative with more aggressive phenotypes of bladder cancer. Meanwhile, gain or loss of function of miR-19a demonstrated that miR-19a can promote cell growth of bladder cancer cells and the further mechanism studies indicated that its oncogenic role was dependent on targeting PTEN. Furthermore, investigation of miR-19a expression in the plasma of bladder cancer patients showed that miR-19a was also increased in plasma of bladder cancer patients which strongly supported miR-19a could be developed as potential diagnostic marker of bladder cancer.

Conclusions

Our data indicated that miR-19a might act as an oncogenic microRNA in bladder cancer and was significantly up-regulated in bladder cancer carcinogenesis. The oncogenic role of miR19a in bladder cancer was dependent on targeting PTEN.     

Research on the antitumor effect of ginsenoside Rg3 in B16 melanoma cells

Ginsenoside Rg3 is an effective chemical component extracted from the red Panix. The experiment demonstrated that it might effectively inhibit proliferation and metastasis of tumor cells. The exact molecular mechanism of Rg3 remains unclear so far. To further explore the antitumor function of Rg3, we investigated the in-vitro and in-vivo activity of Rg3 in the treatment of B16 melanoma cells, derived from C57BL/6 mouse, capable of forming tumor colonies in the lungs following intravenous injection. Cell proliferation was measured by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide assay. Morphological changes of cells were observed by staining with Giesma and Hoechst 33258. Cell cycle and apoptosis rate were analyzed by flow cytometry. The expression of caspase-3 and bcl-2 in cells was detected by immunocytochemistry and western blot analysis. We found that Rg3 could inhibit cell proliferation, regulate cell cycle, and induce cell apoptosis in vitro. B16 melanoma-bearing mice were used to evaluate in vivo the antitumor activity of Rg3. Mice that were injected with Rg3 showed significant inhibition of the tumor metastasis with lighter lung weight, lower density of microvessels, fewer metastasis nodules, and longer survival time than those in the control group (P<0.001). In conclusion, the results reveal that antitumor metastasis of Rg3 is also associated with inducing apoptosis, regulating cell cycle, and blocking angiogenesis in addition to inhibiting proliferation. This research might supply valuable data for chemotherapy with Rg3 in melanoma. Rg3 would turn out to be an anticancer drug with promising prospects.     

Gene silence-induced downregulation of survivin inhibits bladder cancer cells

Urinary bladder cancer accounts for approximately 3% of all cancers in humans. Treatment for urinary bladder is not satisfactory. The present study aims to elucidate the effect of gene silencing of survivin on the inhibition of bladder cancer cells. In this study, we constructed survivin shRNA-carrying lentiviral vectors. Bladder cancer cell lines, T24 cells and BJ cells, were transduced with the constructed shRNA of survivin. The frequency of apoptotic bladder cancer cells was assessed by flow cytometry. The results showed that transfection with survivin shRNA significantly inhibited cell proliferation of both T24 and BJ cells. Most T24 and BJ cells accumulated at the G2/M stage; a portion of them was at sub-G1 stage. An increase in the fraction of bladder cancer cells undergoing apoptosis was noted. Among eight apoptosis-associated proteins, the amounts of BAX and BAD were significantly increased in the survivin-deficient bladder cancer cells. The findings suggest that survivin may be a therapeutic target of bladder cancer to selectively inhibit cell proliferation of bladder cancer cells.