MCAM expression is associated with poor prognosis in non-small cell lung cancer

MCAM has been recently identified as a biomarker for epithelial-mesenchymal transition (EMT) and is potentially involved in metastasis of cancer. The current study aimed at investigating the expression of MCAM in non-small-cell lung cancer (NSCLC) and its clinico-pathological significance.

A follow-up analysis was performed on 118 patients with NSCLC resected by lobectomy or pneumectomy with systematic lymph node dissection. All patients were followed for 6-60 months. Immunostaining of tissue sections from primary tumors and their lymph node metastasis was performed and evaluated using monoclonal antibody against MCAM, E-cadherin, and vimentin. Correlations were investigated between MCAM immunostaining in primary tumors and E-cadherin, vimentin immunostaining, lymph node metastasis, and survival.

MCAM protein expression was found in 46.61 % of squamous cell carcinomas and 37.47 % of adenocarcinomas; MCAM expression positively correlated with vimentin, but inversely with E-cadherin (both P values <0.05). There were significant correlations between the MCAM immunostaining score in primary tumors and in their lymph node metastasis (P = 0.03). According to the Kaplan-Meier survival estimate, the level of MCAM expression in primary tumors was a statistically significant prognostic factor (P < 0.05).

MCAM expression in surgically treated NSCLC is clearly associated with lymph node metastasis and poor prognosis.