Abstract
Solute carrier organic anion transporter family member 4A1 (SLCO4A1) is a membrane transporter protein. The role of this molecule in non‑small cell lung cancer (NSCLC) remains unclear. Bulk sequencing was carried out using early‑stage NSCLC tissues with lymph node metastasis to identify SLCO4A1 that influences NSCLC cell proliferation, metastasis and prognosis. The in vitro functional assays carried out included the following: Cell Counting Kit‑8, plate colony formation, Transwell and wound healing assays. The molecular techniques used included reverse transcription‑quantitative PCR, western blotting and immunohistochemistry. The present study revealed the role of SLCO4A in NSCLC. SLCO4A1 was found to be expressed at high levels in NSCLC tissues and cells, and promotes cell proliferation, migration and invasion. Kaplan‑Meier survival analysis indicated that patients with NSCLC and high expression of SLCO4A1 had a poor prognosis. SLCO4A was revealed to regulate the expression of the proliferation‑related proteins Ki‑67 and PCNA, and that of the extracellular matrix proteins vimentin and E‑cadherin. Mechanistically, SLCO4A1 may affect the MAPK signaling pathway to promote NSCLC cell proliferation, migration and invasion. In addition, bioinformatics analysis demonstrated a strong association between SLCO4A1 and tumor infiltrating immune cells, highlighting its critical role in immune therapies such as immune checkpoint inhibitor treatment of patients with NSCLC.