The implication of LncRNA MALAT1 in promoting chemo‐resistance of laryngeal squamous cell carcinoma cells

BACKGROUND: This study was aimed to evaluate the involvement of lncRNA MALAT1 in modifying chemo‐sensitivity of laryngeal squamous cell carcinoma (LSCC) cell lines. METHODS: Totally 108 pairs of tumor tissues and matched para‐tumor normal tissues were gathered from patients who were pathologically confirmed as LSCC. Meanwhile, LSCC cell lines, including TU686, TU177, AMC‐HN‐8, and LSC‐1, were purchased to evaluate their tolerance to cisplatin, 5‐fluorouracil, paclitaxel, and vincristine. Additionally, CCK‐8 assay, flow cytometry, transwell assay, and wound healing assay were implemented to assess the part of MALAT1 in modulating viability, apoptosis, invasion, and migration of LSCC cell lines. RESULTS: MALAT1 expression was higher in LSCC tissues than in adjacent normal tissues (P < .05), and LSCC patients who carried highly expressed MALAT1 demonstrated poorer 5‐year survival than ones with low MALAT1 expression (P < .05). For another, expression of MALAT1 was also unusually elevated within TU686, TU177, AMC‐HN‐8, and LSC‐1 cell lines as relative to NHBEC cell line (P < .05). The TU686 cell line therein excelled in resisting the growth‐curbing effects of 5‐fluorouracil (IC50 = 20.44 μmol/L), paclitaxel (IC50 = 35.86 μg/L), and vincristine (IC50 = 0.12 μmol/L), when compared with TU177, AMC‐HN‐8, and LSC‐1 cell line (P < .05). Moreover, there seemed great potential for over‐expressed MALAT1 to enhance the chemo‐resistance of both TU686 and LSC‐1 cell lines (P < .05). Not only that, silencing of MALAT1 tended to undermine the proliferative and metastatic power of TU686 and LSC‐1 cell lines (P < .05). CONCLUSION: LncRNA MALAT1 counted in triggering tolerance of LSCC against chemo‐drugs by boosting metastasis and depressing apoptosis of tumor cells.