An in vitro and in vivo study of the role of long non-coding RNA-HOST2 in the proliferation, migration, and invasion of human glioma cells.

Gliomas are the most commonly occurring primary malignant brain tumors in the central nervous system of adults. They are rarely curable and the prognosis for high grade gliomas is generally poor. Recently, long non-coding RNA (lncRNA) human ovarian cancer-specific transcript 2 (HOST2) has been reported to be expressed at high levels in human ovarian cancer, involving tumorigenesis. However, little is still known about whether and how HOST2 regulates glioma development and progression. Therefore, this study aims to investigate the role of HOST2 in human glioma cells. Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) was used to determine the expression of lncRNA HOST2, let-7b, and PBX3 in human glioma cells. Cultured human glioma cells were treated with siRNA (si)-lncRNA HOST2, let-7b mimic, si-lncRNA HOST2 + let-7b inhibitor, and si-PBX3. Parameters including cell viability, colony formation, cell migration, and cell invasion were detected by cell counting kit-8 assay, colony formation assay, scratch test, and Transwell assay respectively to determine the effects of down-regulated HOST2 on glioma cells. Tumor formation in nude mice was evaluated by subcutaneous tumor formation experiment. Results showed that HOST2 and PBX3 were highly expressed in glioma tissue whereas let-7b was expressed at much lower levels. In response to treatment with si-lncRNA HOST2, si-PBX3, and let-7b mimic, glioma cell lines exhibited decreased cell viability, suppressed cell migration, invasion, and reduced colony formation of glioma cells. This was accompanied by an attenuated tumor formation with smaller volume and weight in nude mice, suggesting that down-regulated HOST2 could inhibit the tumorigenicity of glioma cells. Lastly, we found that lncRNA HOST2 was highly expressed in glioma tissues and its down-regulation could inhibit the growth and invasion of glioma cells. © 2018 IUBMB Life, 71(1):93-104, 2019.

Wang Q ，Zhuang ZW ，Cheng YM ，Ma JQ ，Xu SY ，Zhong CL ，Zhang KM ... -  《-》

Effects of LncRNA-HOST2 on cell proliferation, migration, invasion and apoptosis of human hepatocellular carcinoma cell line SMMC-7721.

The present study explored the effect of long non-coding RNA-human ovarian cancer-specific transcript 2 (LncRNA-HOST2) on cell proliferation, migration, invasion and apoptosis of human hepatocellular carcinoma (HCC) cell line SMMC-7721. HCC tissues and adjacent normal tissues from 162 HCC patients were collected. The HCC cell lines were assigned into the control group (regular culture), negative control (NC) group (transfected with siRNA) and experimental group (transfected with Lnc-HOST2 siRNA). Quantitative real-time PCR (qRT-PCR) was used to detect the expression of LncRNA-HOST2. Cell proliferation was detected by CCK-8 and colony-forming assays, cell apoptosis by flow cytometry and cell migration by Scratch test. Transwell assay was used to evaluate cell migration and invasion abilities. LncRNA-HOST2 expression in the HCC tissues increased 2-10 times than that in the adjacent normal tissues. Compared with the HL-7702 cell line, LncRNA-HOST2 expression in HepG2, SMMC-7721 and Huh7 cell lines was all up-regulated, but the SMMC-7721 cell had the highest Lnc-HOST2 expression. The LncRNA-HOST2 expression in the experimental group was down-regulated as compared with the control and NC groups. In comparison with the control and NC groups, cloned cells reduced, cell apoptosis increased, clone-forming ability weakened and inhibitory rate of colony formation increased in the experimental group. The cells migrating and penetrating into the transwell chamber were fewer in the experimental group than those in the control and NC groups. The experimental group exhibited slow wound healing and decreased cell migration area after 48 h. These findings indicate that LncRNA-HOST2 can promote cell proliferation, migration and invasion and inhibit cell apoptosis in human HCC cell line SMMC-7721.

Liu RT ，Cao JL ，Yan CQ ，Wang Y ，An CJ ，Lv HT ... -  《-》

Effects of long non-coding RNA HOST2 on cell migration and invasion by regulating MicroRNA let-7b in breast cancer.

The study intends to investigate the effects of long non-coding RNA HOST2 (lncRNA HOST2) on cell migration and invasion by regulating microRNA let-7b (let-7b) in breast cancer. Breast cancer and adjacent normal tissues were collected from 98 patients with breast cancer. Breast cancer MCF-7 cells were divided into the blank, negative control (NC), pcDNA3-Mock, siHOST2, let-7b inhibitor, pcDNA3-HOST2, let-7b mimic, pcDNA3-HOST2 + let-7b mimic, and siHOST2 + let-7b inhibitor groups. RT-qPCR was used to detect the mRNA expressions of HOST2, let-7b, and c-Myc. Western blotting was conducted to measure the c-Myc expression. Scratch test and Transwell assay were applied to detect the cell motility, migration, and invasion. Xenograft tumor in nude mice was performed to evaluate the effect of different transfection on the tumor growth. Compared with adjacent normal tissues, HOST2 expression was higher but let-7b expression lower in breast cancer tissues. HOST2 expression in breast cancer cells was remarkably increased compared with that in the normal breast epithelial MCF-10A cells. In MCF-7 cells, in comparison with the blank and NC groups, expressions of HOST2 and c-Myc were reduced, but let-7b expression was remarkably elevated in the siHOST2 and let-7b mimic groups; the let-7b inhibitor group exhibited higher expressions of HOST2 and c-Myc but lower let-7b expression. Overexpression of HOST2 could promote cell motility, migration and invasion, thus enhancing the growth of breast cancer tumor. By inhibiting HOST2, opposite trends were found. LncRNA HOST2 promotes cell migration and invasion by inhibiting let-7b in breast cancer patients.

Lu PW ，Li L ，Wang F ，Gu YT ... -  《-》

The expression and significance of lncRNA HOST2 and microRNA let-7b in HPV-positive cervical cancer tissues and cell lines.

Zhang Y ，Jia LG ，Wang P ，Li J ，Tian F ，Chu ZP ，Kang S ... -  《-》

Long noncoding RNA HOST2, working as a competitive endogenous RNA, promotes STAT3-mediated cell proliferation and migration via decoying of let-7b in triple-negative breast cancer.

Hua K ，Deng X ，Hu J ，Ji C ，Yu Y ，Li J ，Wang X ，Fang L ... -  《JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH》