Long non-coding RNA AC105118.1 affects glycolysis to facilitate oxaliplatin resistance in colorectal cancer cells by modulating the miR-378a-3p/KIF26B axis

Abstract

Background

Oxaliplatin is a first-line chemotherapy drug for colorectal cancer (CRC), but many patients eventually lose treatment efficacy due to acquired resistance. AC105118.1 is a long non-coding RNA with unknown biological function. This research attempts to probe into the molecular regulatory mechanism of AC105118.1 in CRC oxaliplatin resistance.

Methods

The expression level of AC105118.1 in CRC tissues and cells was measured based on The Cancer Genome Atlas (TCGA) data and quantitative reverse transcription polymerase chain reaction (qRT-PCR). We utilized dual-luciferase assay and RNA immunoprecipitation to analyze the interaction between AC105118.1, miR-378a-3p, and their downstream target KIF26B. CCK-8, colony formation assay, and flow cytometry were employed to assess the half inhibitory concentration (IC₅₀), cell proliferation, and apoptosis rate of HCT116/L-OHP cells treated with oxaliplatin. The glycolysis evaluation was completed by measuring the extracellular acidification rate (ECAR), glucose consumption, lactate production, and glycolysis-related proteins (HK2, GLUT1, and LDHA). TUNEL staining was used to detect the level of apoptosis.

Results

AC105118.1 was specifically upregulated in CRC tissues and cells. AC105118.1 indirectly facilitated the expression of miRNA target gene KIF26B by sequestering miR-378a-3p. In HCT116/L-OHP cells, transfection with si-AC105118.1 resulted in a decrease in glycolysis level, a lower maximum IC₅₀ required for oxaliplatin-treated cells, inhibited cell proliferation, and an increase in apoptosis rate. All of these effects were alleviated when simultaneously transfecting miR-378a-3p inhibitor or oe-KIF26B. Knockdown of AC105118.1 significantly inhibited oxaliplatin resistance to CRC in mice.

Conclusion

AC105118.1 facilitates glycolysis and increases CRC cells’ resistance to oxaliplatin by targeting the miR-378a-3p/KIF26B axis. The present work shed new insights into the function and mechanism of AC105118.1 in molecular function and suggested that the AC105118.1/miR-378a-3p/KIF26B axis is a promising target for intervening CRC oxaliplatin resistance.