RESUMO
OBJECTIVE To study the mechanism of interfering with long non-coding RNA nicotinamide nucleotide transhydrogenase-antisense RNA1 （LncRNA NNT-AS1） expressing to reduce paclitaxel （TAX） resistance in non-small cell lung cancer （NSCLC） cells. METHODS NSCLC TAX-resistant cell line （A549/TAX） was constructed， and the expressions of LncRNA NNT-AS1 in normal， parental， and drug-resistant cells were observed. The targeting relationship of microRNA-582-5p （miR-582- 5p） with LncRNA NNT-AS1 and high mobility group box2 （HMGB2） was verified. A549/TAX cells were cultured in vitro to observe the effects of interfering with LncRNA NNT-AS1 alone or interfering with LncRNA NNT-AS1 and miR-582-5p on the expressions of LncRNA NNT-AS1 and miR-582-5p， the mRNA and protein expressions of HMGB2， cell viability， clone formation and apoptosis. The effects of interfering with LncRNA NNT-AS1 on tumor growth and the expression of miR-582-5p and the mRNA and protein expressions of HMGB2 in tumor tissue were observed in nude mice. RESULTS Compared with normal cells， LncRNA NNT-AS1 was highly expressed in parental and drug-resistant cells （P＜0.05）， showing an increasing trend. It was validated that miR-582-5p had a targeting relationship with LncRNA NNT-AS1 and HMGB2. After interfering with the expression of LncRNA NNT-AS1， the expression of LncRNA NNT-AS1 and the mRNA and protein expressions of HMGB2， cell viability and the number of cloned cells in A549/TAX cell， decreased significantly， while the expression of miR-582-5p and the apoptotic rate increased significantly （P＜0.05）； simultaneously interfering with the expression of miR-582-5p could reverse above changes （P＜ 0.05）. Interfering with the expression of LncRNA NNT-AS1 in tumor cell could significantly reduce tumor volume and tumor weight of nude mice bearing tumors； at the same time， the expression of miR-582-5p was up-regulated significantly and the mRNA and protein expressions of HMGB2 were down-regulated significantly （P＜0.05）. CONCLUSIONS Interfering with the expression of LncRNA NNT-AS1 may alleviate TAX chemotherapy resistance in NSCLC through targeted up-regulation of miR-582-5p and down-regulation of HMGB2.