LncRNA AK077216 affects the survival of colorectal adenocarcinoma patients via miR-34a

Background and study aimsIt has been reported that long non-coding RNA (lncRNA) AK077216 involves in osteoclastogenesis and bone resorption. Our preliminary data has revealed that AK077216 was downregulated in colorectal adenocarcinoma (CRA) and it was closely correlated with miR-34a. This study was carried out to explore the role of AK077216 in CRA with a focus on its interactions with miR-34a.Patients and methodsPaired CRA and non-tumor tissues collected from 66 CRA patients were subjected to RNA preparations, followed by RT-qPCRs to determine the expression levels of AK077216 and miR-34a. The interactions between AK077216 and miR-34a were analyzed with overexpression assays. Transwell assays were carried out to explore the roles of AK077216 and miR-34a in regulating CRA cell invasion and migration.ResultsAK077216 was downregulated in CRA tissues compared to that in non-tumor tissues of CRA patients. During a 5-year follow-up, patients with lower expression levels of AK077216 in CRA tissues showed significantly lower overall survival. MiR-34a was upregulated in CRA tissues and inversely correlated with AK077216. Overexpression of AK077216 decreased the expression levels of miR-34a, while overexpression of miR-34a did not affect the expression of AK077216. Overexpression of AK077216 inhibited CRA cell migration and invasion, while overexpression of miR-34a accelerated cancer cell migration and invasion and attenuated the effects of overexpression on AK077216 on cell behaviors.ConclusionTherefore, AK077216 may inhibit CRA cell migration and invasion by downregulating miR-34a.     

Evaluation of SNPs in miR-196-a2, miR-27a and miR-146a as risk factors of colorectal cancer

AIM: To investigate whether selected single nucleotide polymorphisms (SNPs) in miR-196a2, miR-27a and miR-146a genes are associated with sporadic colorectal cancer (CRC).METHODS: In order to investigate the effect of these SNPs in CRC, we performed a case-control study of 197 cases of sporadic CRC and 212 cancer-free controls originating from the Central-European Caucasian population using TaqMan Real-Time polymerase chain reaction and allelic discrimination analysis.RESULTS: The genotype and allele frequencies of SNPs were compared between the cases and the controls. None of the performed analysis showed any statistically significant results.CONCLUSION: Our data suggest a lack of association between rs11614913, rs895819 and rs2910164 and colorectal cancer risk in the Central-European Caucasian population, a population with an extremely high incidence of sporadic colorectal cancer.     

肺癌细胞与组织中miR-100、miR-148a的表达变化及临床意义

目的：观察微小RNA 100（miR-100）、微小RNA 148a（miR-148a）在肺癌细胞与组织中的表达,并探讨其临床意义。方法采用RT-PCR方法检测人肺癌细胞系NCI-H1299、NCI-H358、H460、A549及人正常支气管上皮细胞系HBE,以及肺癌及其癌旁组织中miR-100、miR-148a表达;分析肺癌组织中miR-100、miR-148a表达与其临床病理参数的关系。结果与HBE细胞相比,miR-100在NCI-H1299、NCI-H358及A549细胞中表达升高,在H460细胞表达降低,P均＜0．05;miR-148a在NCI-H358、H460细胞中表达升高,在A549细胞中表达降低,P均＜0．05。与癌旁组织相比,肺癌组织中miR-100表达降低,但差异无统计学意义（P＝0．400）;miR-148a表达升高（P＝0．036）。肺癌组织中miR-100、miR-148a表达水平与患者性别、年龄、病理类型无关;有淋巴结转移者肺癌组织中miR-100表达水平较无淋巴结转移者低（P＝0．016）。结论 miR-100、miR-148a在肺癌细胞中表达异常;在肺癌组织中,miR-100表达降低,miR-148a表达增加,二者可能参与肺癌的发生、发展。     

miR-422a is an independent prognostic factor and functions as a potential tumor suppressor in colorectal cancer

AIM: To determine the expression of miR-422a in colorectal cancer (CRC) tissues and to further explore the prognostic value and function of miR-422a in CRC carcinogenesis.METHODS: miR-422a expression was analyzed in 102 CRC tissues and paired normal mucosa adjacent to carcinoma by quantitative real-time PCR. The relationship of miR-422a expression with clinicopathological parameters was also analyzed. Kaplan-Meier analysis and Cox multivariate analysis were performed to estimate the potential role of miR-422a. Cell proliferation, migration, and invasion were used for in vitro functional analysis of miR-422a.RESULTS: The levels of miR-422a were dramatically reduced in CRC tissues compared with normal mucosa (P < 0.05), and significantly correlated with local invasion (P = 0.004) and lymph node metastasis (P < 0.001). Kaplan-Meier survival and Cox regression multivariate analyses revealed that miR-422a expression (HR = 0.568, P = 0.015) and clinical TNM stage (HR = 2.942, P = 0.003) were independent prognostic factors for overall survival in CRC patients. Furthermore, in vitro experiments showed that overexpression of miR-422a inhibited the proliferation, migration, and invasion of SW480 and HT-29 cells.CONCLUSION: Down-regulation of miR-422a may serve as an independent prognosis factor in CRC. MiR-422a functions as a tumor suppressor and regulates progression of CRC.     

MicroRNA-196a抑制序列对人胰腺癌PANC1细胞株HOXB8基因表达的影响

目的 观察microRNA-196a(miR-196a)抑制序列转染胰腺癌细胞株PANC1后对其HOXB8基因表达的影响.方法 将PANC1细胞分为对照组、miR-196a抑制序列组和siRNA对照组.采用脂质体法将miR-196a抑制序列及对照siRNA分别转染PANCI细胞.应用RT-PCR和蛋白质印迹法检测转染细胞miR-196a及其下游靶基因HOXB8 mRNA和蛋白的表达.结果 转染miR-196a抑制序列后,PANC1细胞miR-196a表达量较siRNA对照组显著减少(0.050±0.054比0.839±0.025,t=3.12,P＜0.05);HOXB8 mRNA表达量较siRNA对照组增高1.57倍(2.20 ±0.07比1.29±0.10,t=3.86,P＜0.05);HOXB8蛋白表达量也显著增强(0.90±0.03比0.40±0.10,t=3.11,P＜0.05).结论 miR-196a可以下调HOXB8基因的表达.     

结直肠癌干细胞研究进展

结直肠癌与其他实体肿瘤一样是我国乃至世界范围的重要疾病负担,其治疗也面临许多挑战.近几年,日益受到重视的癌症干细胞理论似乎可以解释结直肠癌的发生发展、复发转移的细胞学机制.本文就结直肠癌干细胞的研究进展作一综述.     

内皮细胞缺氧后miR-210、miR-92a、miR-126表达及意义

目的进一步探讨缺氧后血管新生的调控机制。方法常规方法培养人微血管内皮细胞,低氧培养箱制备内皮细胞缺氧模型（观察组）,正常细胞作为对照组。采用real time PCR法检测两组内皮特异性microRNA（miR-210、miR-92a、miR-126）表达变化。结果与对照组比较,miR-210、miR-92a、miR-126分别上调了（5.19±0.99）、（3.02±0.88）、（3.87±0.83）倍,P均〈0.05。结论缺氧可促使内皮细胞特异性microRNA表达改变,此可能为缺氧后血管新生的主要调控机制。     

体外与非体外循环冠状动脉旁路移植术后血清miR-1、miR-133a、miR-208a水平变化及分析

目的探究行体外循环冠状动脉旁路移植术(ONCABG)与非体外循环冠状动脉旁路移植术(OPCABG)患者术后血清miR-1、miR-133a、miR-208a水平变化。方法选取2016年2月—2019年2月本院多支冠状动脉病变需要行CABG的患者94例。根据手术方式,将94例患者分为ONCABG组47例和OPCABG组47例。利用荧光实时定量PCR法检测所有患者术前、术后不同时间血清miR-1、miR-133a、miR-208a水平。采用化学发光免疫分析仪检测所有患者术前、术后不同时间血清心肌肌钙蛋白I(cTnI)、肌酸激酶同工酶(CK-MB)水平。分析血清miR-1、miR-133a、miR-208a水平与cTnI、CK-MB水平的相关性。结果与术前相比,两组患者术后4 h、24 h血清miR-1、miR-133a、miR-208a、cTnI、CK-MB水平升高(P0.05)。与术后4 h相比,两组患者术后24 h血清miR-1、miR-133a、miR-208a、cTnI、CK-MB水平降低(P0.05)。与ONCABG组相比,OPCABG组术后4 h、术后24 h血清miR-1、miR-133a、miR-208a、cTnI、CK-MB水平降低(P0.05)。Pearson分析显示,两组患者术后4 h、术后24 h血清miR-1、miR-133a、miR-208a水平与cTnI、CK-MB水平均呈正相关(P0.05)。结论 miR-1、miR-133a、miR-208a有望作为判断ONCABG与OPCABG后心肌损伤的重要生物标志物。本研究为ONCABG与OPCABG在临床上的选择提供了一定的参考依据。     

Decreased expression of miR-133a correlates with poor prognosis in colorectal cancer patients

AIM: To investigate microRNA-133a (miR-133a) expression in colorectal cancer (CRC) and its relationship with tumorigenesis and disease prognosis.METHODS: Quantitative real-time polymerase chain reaction was used to measure levels of miR-133a in tumor samples and adjacent non-cancerous tissues from 169 patients undergoing radical resection for CRC. The associations between miR-133a expression and patient age, sex, as well as clinicopathologic parameters, such as tumor size, differentiation, location, invasion depth, metastasis, tumor-node-metastasis (TNM) stage and overall patient survival, were analyzed by Mann-Whitney U and Kruskal-Wallis tests. The Kaplan-Meier method and Cox proportional hazards regression analyses were performed to estimate the prognostic factors for patient survival prediction.RESULTS: The expression of miR-133a was significantly downregulated in CRC tissues compared with adjacent non-cancerous tissues (P < 0.05). This reduction was associated with the depth of the local invasion, poor differentiation, lymph node metastasis and advanced disease (P < 0.05). Moreover, Kaplan-Meier analysis demonstrated that patients with low miR-133a expression had poorer overall survival (OS) than those with high miR-133a expression (P < 0.001). Univariate analysis revealed statistically significant correlations between OS and miR-133a level, tumor local invasion, lymph node metastasis and TNM stage (P < 0.001). Furthermore, miR-133a levels and TNM stage were independently associated with OS (HR = 0.590, 95%CI: 0.350-0.995, P < 0.05; and HR = 6.111, 95%CI: 1.029-36.278, P < 0.05, respectively).CONCLUSION: The downregulation of miR-133a may play an important role in the progression of CRC and can be used as an independent factor to determine CRC prognosis.     

miR-574-3p在结直肠癌中的表达和作用机制研究

目的 检测并分析结直肠癌组织和细胞系中miR-574-3p的表达情况及其对结直肠癌细胞发生、发展的影响.方法 收集武汉市第三医院11对手术切除结直肠癌患者的癌组织和对应癌旁组织,3种结直肠癌细胞系和1种正常结直肠上皮细胞,通过实时荧光定量聚合酶链反应(qRT-PCR)检测临床样本及结直肠癌细胞系中miR-574-3p的...     

Late development of metachronous colorectal cancer

The incidence of metachronous colorectal cancer has been reported to be 1 to 5 percent, with most of the cases being discovered within ten years of the initial cancer. A retrospective review of all colorectal cancer patients was conducted at the Southern Illinois University Affiliated Hospitals to determine the incidence of metachronous colorectal cancer at the authors' institution. In this study, a metachronous cancer was defined as a second colorectal primary occurring at least three years following discovery of the initial lesion. Between 1978 and 1984, there were 24 patients with metachronous colorectal cancer identified in an operative series of 707 patients for a frequency of 3.4 percent. These metachronous cancers were discovered at intervals ranging from 3 to 35 years. Sixteen (67%) metachronous lesions occurred 11 years of more after the original cancer. Synchronous or interval adenomatous colorectal polyps were noted in 17 (71 percent) of the patients. Thirteen of the metachronous cancers appeared in the right colon, while six were distributed throughout the transverse and descending colon, and five were in the rectosigmoid region. The incidence of late-appearing metachronous colorectal cancers and the propensity to occur in the right colon underscores the need for evaluation of the entire colon as part of lifelong follow-up of the colorectal cancer patient. Read the meeting of the American Society of Colon and Rectal Surgeons, Houston, Texas, May 11 to 15, 1986.     

miR-132 inhibits colorectal cancer invasion and metastasis via directly targeting ZEB2

AIM:To investigate the biological role and underlying mechanism of miR-132 in colorectal cancer(CRC)progression and invasion.METHODS:Quantitative RT-PCR analysis was used to examine the expression levels of miR-132 in five CRC cell lines(SW480,SW620,HCT116,HT29 and LoVo)and a normal colonic cell line NCM460,as well as in tumor tissues with or without metastases.The KaplanMeier method was used to analyze the prognostic significance of miR-132 in CRC patients.The biological effects of miR-132 were assessed in CRC cell lines using the transwell assay.Quantitative RT-PCR and western blot analyses were employed to evaluate the expression of miR-132 targets.The regulation of ZEB2 by miR-132was confirmed using the luciferase activity assay.RESULTS:miR-132 was significantly down-regulated in the CRC cell lines compared with the normal colonic cell line(P<0.05),as well as in the CRC tissues withdistant metastases compared with the tissues without metastases(10.52±4.69 vs 23.11±7.84)(P<0.001).Down-regulation of miR-132 was associated with tumor size(P=0.016),distant metastasis(P=0.002),and TNM stage(P=0.020)in CRC patients.Kaplan-Meier survival curve analysis indicated that patients with low expression of miR-132 tended to have worse diseasefree survival than patients with high expression of miR-132(P<0.001).Moreover,ectopic expression of miR-132 markedly inhibited cell invasion(P<0.05)and the epithelial-mesenchymal transition(EMT)in CRC cell lines.Further investigation revealed ZEB2,an EMT regulator,was a downstream target of miR-132.CONCLUSION:Our study indicated that miR-132 plays an important role in the invasion and metastasis of CRC.     

A variant in microRNA-196a2 is not associated with susceptibility to and progression of colorectal cancer in Chinese

Background: MicroRNAs (miRNAs) are small non‐coding RNAs with regulatory functions as tumour suppressors and oncogenes. Although single nucleotide polymorphism (SNP) in miRNA regions have been reported to be rare and unlikely to be functionally important, recent evidence suggested that rs11614913 SNP in miR‐196a2 was associated with the susceptibility of lung cancer, breast cancer, congenital heart disease and shortened survival time of non‐small‐cell lung cancer. Aims: The aim of this study was to investigate the association between this genetic variant and the risk and/or progression of colorectal cancer (CRC). Methods: A total of 126 CRC patients and 407 healthy controls was periodically enrolled. DNA was extracted from blood specimens, and miR‐196a2 polymorphism was genotyped by polymerase chain reaction–ligation detection reaction (PCR–LDR). Results: Although the frequency of CC homozygotes or miR‐196a2C allele‐containing genotypes (CT and CC) was lower in CRC patients than in the healthy controls, no significant association between miR‐196a2 polymorphism and the risk of CRC was found. The frequency of the ‘C’ allele in CRC patients was also not significantly lower than in healthy controls. In a subsequent analysis of the association between this polymorphism and the progression of CRC, there was still no significant difference in both genotype and allelic frequency. Conclusions: Our results suggest that miR‐196a2 polymorphism is not associated with both an increased risk and progression of CRC in Chinese.     

Unlocking the ultrastructure of colorectal cancer cells in vitro using selective staining

AIM: To characterise differences between three widely used colorectal cancer cell lines using ultrastructural selective staining for glycogen to determine variation in metastatic properties. METHODS: Transmission electron microscopy was used in this investigation to help identify intracellular structures and morphological features which are precursors of tumor invasion. In addition to morphological markers, we used selective staining of glycogen as a marker for neoplastic cellular proliferation and determin...     

Chemopreventive drugs:Mechanisms via inhibition of cancer stem cells in colorectal cancer

Recent epidemiological studies,basic research and clinical trials on colorectal cancer(CRC)prevention have helped identify candidates for effective chemopreventive drugs.However,because of the conflicting results of clinical trials or side effects,the effective use of chemopreventive drugs has not been generalized,except for patients with a high-risk for developing hereditary CRC.Advances in genetic and molecular technologies have highlighted the greater complexity of carcinogenesis,especially the heterogeneity of tumors.We need to target cells and processes that are critical to carcinogenesis for chemoprevention and treatment of advanced cancer.Recent research has shown that intestinal stem cells may serve an important role in tumor initiation and formation of cancer stem cells.Moreover,studies have shown that the tumor microenvironment may play additional roles in dedifferentiation,to enable tumor cells to take on stem cell features and promote the formation of tumorigenic stem cells.Therefore,early tumorigenic changes of stem cells and signals for dedifferentiation may be good targets for chemoprevention.In this review,I focus on cancer stem cells in colorectal carcinogenesis and the effect of major chemopreventive drugs on stem cell-related pathways.