靶向沉默NOB1基因对乳腺癌细胞MCF-7生长和周期分布的影响

背景与目的:NOB1(NIN1/RPN12 binding protein 1 homolog)是2005年新克隆的一个基因,属于RNA结合蛋白,该类蛋白的功能与恶性肿瘤的发生密切相关。本研究旨在观察利用慢病毒介导的RNAi沉默NOB1基因对人乳腺癌MCF-7细胞增殖及细胞周期的影响。方法:包装表达NOB1短发夹RNA(shRNA)的慢病毒,感染MCF-7细胞,实时定量PCR和蛋白质印迹法(Western blot)验证NOB1的抑制效率;MTT和克隆形成实验检测NOB1对细胞增殖能力的影响;流式细胞术检测细胞周期的变化。结果:NOB1-shRNA慢病毒感染3 d后,可显著下调MCF-7细胞NOB1 mRNA和蛋白的表达水平,显著抑制细胞增殖和体外成瘤能力,并导致细胞周期分布紊乱,G0/G1期及G2/M期细胞增加,S期细胞减少。结论:NOB1基因通过调节细胞周期分布促进乳腺癌细胞恶性增殖,可能是乳腺癌基因治疗的分子靶点。     

过表达lnc-TNFAIP3基因对胰腺癌PANC-1细胞生物学行为的影响

目的:应用慢病毒转染方法构建lnc-TNFAIP3基因过表达的胰腺癌细胞株,并观察其细胞行为学变化。方法:过表达质粒和慢病毒制备,转染进人胰腺癌细胞株PANC-1中,采用CCK-8、平板克隆实验检测其细胞增殖能力,划痕实验和Transwell实验检测细胞迁移和侵袭能力,Western blot检测蛋白表达,流式细胞术检测细胞周期和细胞凋亡情况。结果:lnc-TNFAIP3基因过表达慢病毒成功转染PANC-1细胞,其细胞增殖、迁移和侵袭能力减弱,细胞周期和细胞凋亡无显著差异,相关蛋白表达无显著差异。结论:转染过表达lnc-TNFAIP3基因的慢病毒构建的人胰腺癌细胞系PANC-1细胞行为发生了变化,提示lnc-TNFAIP3可能是一个有前景的胰腺癌治疗靶点,为lnc-TNFAIP3基因在胰腺癌中的研究提供了理论和实验数据。     

NOB1 in Non-small-cell Lung Cancer: Expression Profile and Clinical Significance

Nin one binding (NOB1) gene has been reported up-regulated in several types of cancer. The aim of this study was to investigate the expression profile of NOB1 in non-small-cell lung cancer (NSCLC) and assess the clinical significance. qRT-PCR was used in the detection of NOB1 mRNA expression both in NSCLC tissue and in adjacent normal lung tissue. Western blot analysis and immunohistochemistry were used in the detection of NOB1 protein expression. The clinicopathological implications of NOB1 were analyzed statistically. It was confirmed by RT-qPCR that expression of NOB1 mRNA in NSCLC cells was higher than in human lung cells (P?<?0.05), and NOB1 mRNA was also over-expressed in NSCLC tissue when compared with adjacent tissue and normal lung tissue (P?<?0.05). Western blot analysis showed that NOB1 protein was significant increased in NSCLC cell lines compared with human lung cell line. Western blot analysis and immunohistochemistry showed that NOB1 protein was significant increased in NSCLC tissue compared with adjacent tissue and normal lung tissue (P?<?0.05). There were significant associations between NOB1 expression and TNM stage, lymph node metastasis, and histopathological grade (P?<?0.05), but not gender, age, smoke, or tumor diameter (P?>?0.05). Our results suggest that enhanced expression of NOB1 gene plays an important role in the occurrence and development of NSCLC. NOB1 may be a potential therapeutic target in NSCLC.     

shRNA-mediated silencing of ZFX attenuated the proliferation of breast cancer cells

Purpose

Breast cancer is the cause for highest number of cancer-related death among women worldwide. This study was focused on investigating the role of zinc-finger protein X-linked (ZFX) in human breast cancer.

Methods

Expression levels of ZFX were analyzed in 99 patients and four breast cancer cell lines. Lentivirus-mediated RNA interference was applied to silence ZFX expression, and the effects of ZFX knockdown on the growth of breast cancer cells were investigated.

Results

The immunohistochemical expression of ZFX was higher in more advanced tumor tissues. ZFX was also overexpressed in multiple breast cancer cell lines. Knockdown of ZFX inhibited cell proliferation and colony formation of MCF-7 and MDA-MB-231 cells. Moreover, ZFX silencing resulted in cell cycle arrest at G0/G1 phase. Depletion of ZFX decreased the phosphorylation level of AKT and increased the phosphorylation level of ERK2 and the expression of cyclin D1, which is involved in cell survival and cell cycle regulation.

Conclusions

These findings suggest that ZFX plays an important role in breast cancer development and could be a potential therapeutic target for breast cancer.     

Inhibition of heregulin mediated MCF-7 breast cancer cell growth by the ErbB3 binding protein EBP1

The ErbB2/3 heterodimer plays a critical role in breast cancer genesis and progression. EBP1, an ErbB3 binding protein, inhibits breast cancer growth but its effects on ErbB3 ligand mediated signal transduction or ErbB receptors is not known. We report here that ectopic expression of EBP1 in MCF-7 and AU565 breast cancer cell lines inhibited HRG-induced proliferation. ErbB2 protein levels were substantially decreased in EBP1 transfectants, while ErbB3 levels were unchanged. HRG-induced AKT activation was attenuated in EBP1 stable transfectants and transfection of a constitutively activated AKT partially restored the growth response to HRG. Down-regulation of EBP1 expression in MCF-7 cells by shRNA resulted in increased cell growth in response to HRG and increased cyclin D1 and ErbB2 expression. These results suggest that EBP1, by down-regulating ErbB signal transduction, attentuates HRG-mediated growth of breast cancer cells.     

RNAi-mediated downregulation of <Emphasis Type="Italic">NOB1</Emphasis> suppresses the growth and colony-formation ability of human ovarian cancer cells

Nin one binding protein (NOB1p), encoded by the NOB1 gene, is a crucial molecule in the maturation of the 20S proteasome and protein degradation. The present study evaluates whether NOB1 is an appropriate molecular target for cancer gene therapy. In two ovarian cancer cell lines, SKOV3 and HEY, NOB1 expression was knocked down by a lentiviral short hairpin RNA (shRNA) delivery system. The RNA interference (RNAi)-mediated the downregulation of NOB1 expression markedly reduced the proliferative and colony-formation ability of ovarian cancer cells. Additionally, NOB1 shRNA-expressing lentivirus-treated ovarian cancer cells tended to arrest in the G0/G1 phase. These results suggested that NOB1 may act as an oncogenic factor in ovarian cancer and could be a potential molecular target for ovarian cancer gene therapy.     

FSIP1 is correlated with estrogen receptor status and poor prognosis

Fibrous sheath interacting protein 1 (FSIP1) is frequently activated in a variety of tumors including breast cancer. However, the clinical significance of FSIP1 in hormone receptor (HR)-positive breast cancer is unclear. We analyzed the expression and clinical significance of FSIP1 in human breast cancer databases. A comprehensive analysis of 1094 gene expression profiles of breast cancer in The Cancer Genome Atlas revealed that FSIP1 overexpression correlated with decreased overall survival in HR-positive breast cancer patients. We also showed that knockdown of FSIP1 in T47D and BT474 cell lines resulted in decreased cell proliferation and migration in vitro. Furthermore, we retrospectively examined the expression and prognostic value of FSIP1 in 129 breast cancer patients to examine the expression of FSIP1 by the immunohistochemical method and got the similar results that high expression of FSIP1 predicts poor prognosis. Therefore, FSIP1 has a crucial role in HR-positive breast cancer and represents an attractive therapeutic target for HR-positive breast cancer.     

Effect of RNA silencing of polo-like kinase-1 (PLK1) on apoptosis and spindle formation in human cancer cells

BACKGROUND: Expression of polo-like kinase-1 (PLK1), which has several functions in mitotic progression, is elevated in a broad range of human tumors. To investigate the role of PLK1 in neoplastic proliferation, we used the technique of RNA interference. METHODS: Cells from several different cancer cell lines (MCF-7 breast cancer cells, HeLa S3 cervical cancer cells, SW-480 colon cancer cells, and A549 lung cancer cells) were transfected with small interfering (si) RNAs targeted against the human PLK1 or lamin genes. Northern and western blot analyses were used to examine PLK1 gene expression in transfected cancer cells and normal cells (human mammary epithelial cells [HMECs]). The phenotype, proliferation, and cell cycle distribution of cells transfected with siRNAs were also monitored by fluorescence microscopy and fluorescence-activated cell sorting analysis. RESULTS: All cancer cell lines transfected with low doses of siRNAs targeted to PLK1 had greatly decreased levels of PLK1 mRNA and protein. siRNA4, which had the strongest inhibitory effect, reduced PLK1 mRNA in MCF-7 cells by 70% and PLK1 protein in MCF-7 cells by 95% 24 hours after transfection. Cell proliferation was reduced by between 66% and 99% 48 hours after transfection, and apoptosis was increased from 1%-5% to 13%-50% in transfected cells. Transfected SW-480 cells were mitotically arrested, and their centrosomes had lost the ability to nucleate microtubules. HMECs took up siRNAs less efficiently than cancer cells, and transfection with siRNAs targeted to PLK1 did not inhibit their proliferation. CONCLUSIONS: PLK1 function appears to be essential for centrosome-mediated microtubule events and, consequently, for spindle assembly. siRNAs targeted against human PLK1 may be valuable tools as antiproliferative agents that display activity against a broad spectrum of neoplastic cells at very low doses.     

Exogenous expression of UHRF1 promotes proliferation and metastasis of breast cancer cells

In the present study, we investigated the role of UHRF1 (ubiquitin-like protein containing PHD and RING finger domains 1) in proliferation, invasion and migration of breast cancer cells, and the potential mechanisms were also explored. Cell proliferation was examined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay; cell cycle distribution and apoptosis were evaluated using flow cytometry; protein expression was determined by western blotting; angiogenesis of xenografts was assessed by microvessel density (MVD); cell invasion was measured using transwell chamber; cell migration was determined by wound scratching assay. Our results demonstrated that UHRF1 transfection conferred serum independence to MDA-MB-231 cells, G1 phase shortage and apoptosis suppression, accompanied with an increased expression of cyclin D1 and decreased expression of Bax. Significant pro-invasion and pro-migration activity was observed, with no obvious effect on the expression of PTEN and maspin. Co-expression of the UHRF1/PTEN or UHRF1/maspin degraded the role of UHRF1 in regulating invasion and migration. UHRF1 induced growth of MDA-MB-231 cells by promoting tumor vessel formation in vivo. In conclusion, UHRF1 promoted the proliferation of breast cancer cells by apoptosis inhibition, G1 phase shortage and promotion of tumor vessel formation, and pro-invasion and pro-migration activity was also observed by interacting with PTEN and maspin. Thus, UHRF1 may serve as a new therapy target for breast cancer.     

The expression and functional characterization of sigma (sigma) 1 receptors in breast cancer cell lines

Sigma (sigma) receptors have been implicated in cancer. However, to date there is little molecular data demonstrating the role of sigma1 receptors in cancer. Expression of sigma1 receptors in various human cancer cell lines in comparison to non-cancerous cell lines was investigated, using real time RT-PCR and by western blotting with a sigma1 receptor specific antibody. Our results indicate that cancer cells express higher levels of sigma1 receptors than corresponding non-cancerous cells. Localization of the sigma1 receptor was investigated in MDA-MB-231 cells by immunocytochemistry and confocal microscopy, expression was visualized predominantly at the cell periphery. We have tested the effect of sigma1 and sigma2 drugs and a sigma1 receptor silencing construct on various aspects of the metastatic process on two breast cell lines of different metastatic potential and a normal breast cell line. Both sigma1 and sigma2 drugs and the sigma1 receptor silencing construct had effects on proliferation and adhesion for breast cancer cell lines, compared to a non-cancerous breast cell line. This data suggests sigma1 receptor plays a role in proliferation and adhesion of breast cancer cells. Therefore, it is likely to be a potential target for the diagnosis and therapy of breast cancer.     

siRNA沉默HYAL1基因表达对人乳腺癌细胞生长和增殖的影响

背景与目的：有研究证实透明质酸酶（hyaluronidase,Hyase）与人乳腺癌的恶性潜能相关。本研究拟探讨RNA干扰是否能有效抑制Hyde基因HYAL1的表达以及人乳腺癌细胞的生长和增殖。方法：体外化学合成HYAL1序列特异性双链RNA（dsRNA）,在脂质体（SiPORT Lipid）的介导下转染人乳腺癌细胞株MDA-MB-231、MDA-MB-453S、ZR-75和ZR-75-30。荧光共聚焦显微镜下观察转染效率,RT-PCR分析HYAL1 mRNA的表达,MTT测定细胞的增殖,流式细胞仪测定细胞周期。结果：（1）HYAL1-siRNA能有效地封闭HYALl基因的表达．使HYAL1 mRNA相对水平明显降低（P〈0．05）;（2）HYAL1-siRNA能明显抑制细胞增殖（P〈0．05）;（3）HYAL1-siRNA使细胞周期G0／G1期细胞百分比明显增加,S期的细胞百分比显著减少（P〈0．05）。结论：siRNA-HYAL1能有效抑制人乳腺癌细胞株HYAL1基因的表达,抑制细胞增殖,将更多的细胞阻滞在G0／G1期。     

KIFC1 is a novel potential therapeutic target for breast cancer

Kinesin-like protein KIFC1, a normally nonessential kinesin motor, plays a critical role in centrosome clustering in cancer cells and is essential for the survival of cancer cells. Herein, we reported that KIFC1 expression is up-regulated in breast cancer, particularly in estrogen receptor negative, progesterone receptor negative and triple negative breast cancer, and is not associated with epidermal growth factor receptor 2 status. In addition, KIFC1 is highly expressed in all 8 tested human breast cancer cell lines, but is absent in normal human mammary epithelial cells and weakly expressed in 2 human lung fibroblast lines. Moreover, KIFC1 silencing significantly reduced breast cancer cell viability. Finally, we found that PJ34, a potent small molecule inhibitor of poly(ADP-ribose) polymerase, suppressed KIFC1 expression and induced multipolar spindle formation in breast cancer cells, and inhibited cell viability and colony formation within the same concentration range, suggesting that KIFC1 suppression by PJ34 contributes to its anti-breast cancer activity. Together, these results suggest that KIFC1 is a novel promising therapeutic target for breast cancer.     

The tumor suppressor gene LKB1 is associated with prognosis in human breast carcinoma.

PURPOSE: LKB1 (also called STK11) is a recently identified tumor suppressor gene in which its mutation can lead to Peutz-Jeghers syndrome, characterized by gastrointestinal polyps and cancers of different organ systems. Weak expression of this gene does occur at a certain frequency in sporadic breast cancer. This indicates that LKB1 gene may relate to the tumorigenesis of breast cancer. EXPERIMENTAL DESIGN: To investigate the function of the LKB1 gene in sporadic breast cancer, we reintroduced LKB1 into breast cancer cell lines which lack the LKB1 gene. Also, we examined the LKB1 protein expression in human breast cancer samples. RESULTS: We found that reintroducing LKB1 into breast cancer cell lines suppresses cell growth by G(1) cell cycle block. The LKB1-mediated G(1) cell cycle arrest is caused by up-regulation of the expression of p21(WAF1/CIP1) in breast cancer MDA-MB-435 cells. We also demonstrated that low LKB1 protein expression correlates with higher histological grade (P = 0.013), larger tumor size (P = 0.001), progesterone receptor status (P = 0.048), and presence of lymph node metastasis (P = 0.003). Furthermore, LKB1 low expression was associated with a higher relapse rate (P = 0.002) and a worse OS (P = 0.008). CONCLUSIONS: LKB1 plays a role in tumor suppressor function in human breast cancer. LKB1 expression may be a useful prognostic marker in human breast cancer.     

Role of TMPRSS4 Modulation in Breast Cancer Cell Proliferation

Background: TMPRSS4 is a novel Type II transmembrane serine protease found at the surface of the cells andis involved in the development and cancer progression. However, TMPRSS4 functions in breast cancer remain poorunderstand. The present study investigated the function of TMPRSS4 in the breast cancer cells and the potentialmechanistic action underling. Materials and Methods: The lentiviral vectors causing TMPRSS4 down-regulation andover-expression were established and transfected in MDA-MB-468 and MCF-7 cells, respectively. By using the CCK-8 assay, cell proliferation was analyzed. Moreover, western blot was used to detect the expression of certain proteinsrelated to cell apoptosis (Bax and Bcl2) signaling pathway and telomere maintenance (POT1, TPP1, and UBE2D3).Cell cycle and cell apoptosis were also analyzed by using the Flow cytometry analysis. TMPRSS4 expression wasdetected at the mRNA level and protein level by performing qPCR and western blot technique, respectively. Results:TMPRSS4 expression is inhibited in stable transfected MDA-MB-468-shTMPRSS4 cells compared to the controlMDA-MB-468-NC and its expression is up-regulated in stable transfected MCF-7-TMPTSS4 compared to its controlMCF-7-NC. Moreover, TMPRSS4 silencing in breast cancer reduces cells proliferation by promoting cell cycle arrestin G2/M phase, cell apoptosis, and telomere maintenance impairment while the TMPRSS4 overexpression increasescells proliferation through cell apoptosis reduction and telomere maintenance reinforcement associated with insignificantchange in cell cycle progression. Conclusion: TMPRSS4 plays important roles in cancer progression and may beconsidered as a good therapeutic target for cancer gene therapy especially breast cancer.