Expression levels of Filamin A protein predict survival outcomes in non-small cell lung cancer patients treated with Carboplatin and Navelbine

Objective: Resistance to cytotoxic chemotherapeutic drugs represent the major impediment for the successful treatment of non-small cell lung cancer patients. Recently, it has been shown that cytoskeletal protein Filamin A is required for efficient DNA damage repair and modulates cisplatin sensitivity in vitro. We investigated the relationship between the expression levels of filamin A protein and survival outcomes in non-small cell lung cancer patients, treated with adjuvant Carboplatin and Navelbine.

Methods: We analysed filamin A protein expression in resection specimens from 135 non-small cell lung cancer patients, from which 73 patients were treated with adjuvant Carboplatin and Navelbine, and 62 patients did not receive adjuvant treatment. Archived formalin-fixed and paraffin-embedded (FFPE) tissue sections were stained immunohistochemically using EP2405Y antibody against C-terminus of filamin A.

Results: Cox regression analysis of survival showed that increased expression of filamin A protein (histoscore > 90) is significantly related with shorter overall survival (HR = 1,005, 95 % CI (1,000; 1,010), p = 0,037) and disease free survival (HR = 1,004, 95 % CI (1,001: 1,008), p = 0,017) in patients with adjuvant platinum-based chemotherapy. Such relationship was not seen in patients without adjuvant treatment.

Conclusion: Filamin A expression might re­present a novel potential predictive marker of platinum-based treatment outcome in patients with non-small-cell lung cancer.