Effects of long non-coding RNA ALMS1-IT1 on the proliferation and migration of colorectal cancer cells via regulating the expressions of miRNA-889-3p and ATAD2 / 肿瘤研究与临床

ABSTRACT

Objective:To investigate the expression of long non-coding RNA (lncRNA) ALMS1-IT1 in colorectal cancer tissues and the molecular mechanism of its effect on the proliferation and migration of colorectal cancer HT-29 cells in vitro.Methods:The cancer tissue specimens and paracancerous tissue (>5 cm from the edge of the tumor) specimens were collected from 40 colorectal cancer patients who were diagnosed by pathological examination after surgical resection in Hubei 672 Orthopedic Hospital of Integrated Traditional Chinese and Western Medicine from July 2018 to November 2020. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression level of ALMS1-IT1 in colorectal cancer tissues and paracancerous tissues, when the relative expression of ALMS1-IT1 was higher than or equal to its median relative expression, ALMS1-IT1 was highly expressed, and the correlation of ALMS1-IT1 expression with the clinicopathological characteristics of patients was analyzed. HT-29 cells were infected with the empty lentivirus and the lentivirus carrying the ALMS1-IT1 silence sequence, and named control group and si-ALMS1-IT1 group. qRT-PCR was used to detect the expression of ALMS1-IT1 in the two groups of HT-29 cells. CCK-8 method and Transwell experiment were used to detect the proliferation and migration ability of the two groups of HT-29 cells. The starBase v2.0 online database was used to predict ALMS1-IT1 interacting molecules, and qRT-PCR and Western blot were used to detect the expression of these molecules.Results:The relative expression of ALMS1-IT1 in colorectal cancer tissues was higher than that in paracancerous tissues (4.54±0.61 vs. 1.19±0.31, t = 34.89, P < 0.01). The median relative expression of ALMS1-IT1 in cancer tissues of 40 patients was 2.93, and the high expression rate of ALMS1-IT1 was 50.0% (20/40). The high expression rate of ALMS1-IT1 in cancer tissues of TNM stage Ⅲ patients was higher than that in TNM stage Ⅰ-Ⅱ patients, the high expression rate of ALMS1-IT1 in poorly-differentiated patients was higher than that in well- and moderately-differentiated patients, and the high expression rate of ALMS1-IT1 in patients with lymph node metastasis was higher than that in patients without lymph node metastasis (all P < 0.01). The cell proliferation capacity (absorbance value) of HT-29 cells in the si-ALMS1-IT1 group after cultured for 2, 3, 4, and 5 days was lower than that in the control group (all P < 0.05). The number of cell migration at 24 h in HT-29 cells of the si-ALMS1-IT1 group was less than that of the control group (45±7 vs. 112±18, t = 3.45, P < 0.05). Using starBase v2.0 online database to predict that the target gene of ALMS1-IT1 may be miRNA-889-3p (miR-889-3p), and the target gene of miR-889-3p may be ATAD2. Compared with the control group, the relative expression of miR-889-3p in HT-29 cells of the si-ALMS1-IT1 group increased (4.24±0.46 vs. 1.01±0.11, t = 6.81, P < 0.01). Compared with the control group, ATAD2 mRNA ( P < 0.01) and protein expression levels in the si-ALMS1-IT1 group were reduced. Conclusions:ALMS1-IT1 is highly expressed in colorectal cancer tissues, and the ALMS1-IT1 expression is related to the TNM stage, degree of tumor differentiation and lymph node metastasis of patients. Down-regulation of ALMS1-IT1 in vitro may inhibit the proliferation and migration of colorectal cancer HT-29 cells by regulating the miR-889-3p-ATAD2 axis. ALMS1-IT1 may be a therapeutic target for colorectal cancer.