Effect of long non-coding RNA SLCO4A1-AS1 targeting microRNA-615-5p on the proliferation, apoptosis and inflammatory factors expression in esophageal cancer cells

Objective To investigate the effects of long non-coding RNA (LncRNA) solute carrier organic anion transporter family member 4A1 (SLCO4A1-AS1) targeting microRNA-615-5p (miR-615-5p) in esophageal cancer cells on cell proliferation, apoptosis, and expression of inflammatory factors.

Methods Real-time quantitative polymerase chain reaction (RT-qPCR) was used to analyze the expression of LncRNA SLCO4A1-AS1 and miR-615-5p in esophageal cancer tissues and cell lines. Eca109 cells were transfected with si-NC, si-LncRNA SLCO4A1-AS1, miR-NC, miR-615-5p mimic, pcDNA, pcDNA-LncRNA SLCO4A1-AS1, si-LncRNA SLCO4A1-AS1+anti-miR-NC, and si-LncRNA SLCO4A1-AS1+anti-miR-615-5p. Cell viability and apoptosis rate were measured by CCK-8 and flow cytometry, respectively; cell proliferation was determined by plate cloning assay; and levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in the culture medium were measured using an enzyme-linked immunosorbent assay (ELISA) kit. A dual luciferase reporter gene assay was used to determine the relationship between LncRNA SLCO4A1-AS1 and miR-615-5p.

Results Expression of LncRNA SLCO4A1-AS1 was upregulated, and miR-615-5p expression was downregulated in esophageal cancer tissues and cell lines. After inhibiting LncRNA SLCO4A1-AS1 expression, cell viability, the number of cell clones, and levels of IL-6 and TNF-α in the culture medium decreased, while miR-615-5p expression and apoptosis rate increased (P < 0.05). Compared with the miR-NC group, the miR-615-5p group showed increased miR-615-5p expression, levels of Cleaved-caspase-3 protein, and apoptosis rate, and decreased cell viability, the number of cell clones, and levels of IL-6 and TNF-α in the culture medium (P < 0.05). Compared with the si-LncRNA SLCO4A1-AS1+anti-miR-NC group, the si-LncRNA SLCO4A1-AS1+anti-miR-615-5p group showed decreased miR-615-5p expression, levels of Cleaved-caspase-3 protein, and apoptosis rate, and increased cell viability, the number of cell clones, and levels of IL-6 and TNF-α in the culture medium (P < 0.05).

Conclusion LncRNA SLCO4A1-AS1 can promote the occurrence and development of esophageal cancer. Inhibiting LncRNA SLCO4A1-AS1 can reduce the proliferation of esophageal cancer cells, decrease the expression of inflammatory factors, and induce apoptosis.