[Expression of microtubule-associated protein 1 light chain 3 in laryngeal carcinoma].

ABSTRACT

OBJECTIVE: To investigate the expression of microtuble-associated protein 1 light chain 3 (LC3) in laryngeal squamous cell carcinoma (LSCC). METHOD: The expression of LC3 in 50 cases of LSCC, 45 cases of para-carcinoma, 10 cases of laryngeal papilloma and 16 cases of polyp of vocal cord were detected by immunohistochemistry (MaxVision method). Expression level of LC3 mRNA was assayed by RT-PCR in 41 of LSCC, 41 of para-carcinoma tissue and 11 of polyp of vocal cord. RESULT: The positive rates of LC3 protein expression were 60.0%, 93.3%, 90.0%, 93.8% in LSCC tissue, para-carcinoma, laryngeal papilloma and poly of vocal card tissues, respectively. The positive rates of LC3 were significantly lower in LSCC than in para-carcinoma and poly of vocal cord (chi2 = 18.135, P < 0.01). The mRNA levels of LC3 were significantly lower in LSCC than in para-carcinoma and poly of vocal cord (0.57 +/- 0.08 )vs (0.99 +/- 0.11) and (1.07 +/- 0.05) , F = -255.872, P < 0.01. The expression of LC3 were related to tumor location and pathological grade (P < 0.05), but not related to age, T stage, clinical stage and lymphoid metastasis (P > 0.05). CONCLUSION: Expression of LC3 are down-regulated in LSCC. The change of autophagic capacity may play an important role in occurrence and development of LSCC.