The Expression And Function Of Long Non-coding RNA 91H In Colorectal Cancer

Objective: Recently, accumulated research data have shown that lnc RNAs(long non-coding RNA) play a critical role in the carcinogenesis and development of malignancy. Moreover, the existing evidence showed that lnc RNA 91 H is overexpressed in the tissues of breast cancer, and involved in the regulation of IGF2 expression in trans. This study was performed to explore clinical relevance and biological functions of 91 H in colorectal cancer(CRC), and initially revealed the impact of 91 H on CRC and its molecular mechanisms to provide a theoretical basis of clinical molecular targeted therapy for CRC.Methods: 1. 72 CRC tumor tissues and adjacent normal tissues were collected. CRC cell lines(HCT-8, HT-29, HCT-116, SW-620) and FHC were obtained from Chinese Academy of Science. 2. The microsatellite instability was detected in CRC tumor tissues by PCR. 3. 91 H expression were measured in tissue samples, four CRC cell lines and normal FHC cell line by real-time quantitative PCR(RT-q PCR) to make sure of the cell line with the highest levels of 91 H expression, and copy number variations(CNVs) were also measured in tissue samples by RT-q PCR to further analyze the correlation of 91 H expression, CNV and clinical characteristics 4. 91 H interference fragments were constructed and transfected into HCT-116 by Lip 2000 and the transfection efficiency was assessed by RT-q PCR. 5. The biological roles of 91 H were evaluated by MTT, flow cytometry, scratch wound assay, migration and invasion assays.Results: 1. 91 H relative expression levels in cancer tissues was 6.10±3.12 folds of theadjacent normal tissues(P < 0.05). 2. The results of clinicopathological analysis showed that 91 H overexpression was significantly associated with tumor metastasis(P=0.027). Kaplan-Meier curve analysis revealed that patients with 91 H overexpression had a longer overall survival than those with 91 H low expression(P<0.001). Multivariate analysis showed that 91 H expression was considered as an independent risk factor for CRC patients(HR=3.66, 95% CI=1.66-8.10, P=0.001). 3. 91 H expression in cancerous and non-cancerous tissues was not associated with CNV(P>0.05). 4. Compared with the normal cell line FHC, 91 H was overexpressed in cell lines HCT-8, HT-29 and HCT-116(P<0.05), except for SW-620(P>0.05), and 91 H expression in HCT-116 was the highest levels among them. 5. Our results in vitro showed that knockdown of 91 H inhibited the proliferation, migration, and invasiveness of CRC cells.Conclusions: 1. 91 H overexpression was closely associated with tumor metastasis and poor prognosis, and could be considered as a novel biomarker to evaluate clinical prognosis for CRC patients. 2. 91 H overexpression may promote the the proliferation, migration, and invasiveness of CRC cells...