The role of folate receptor alpha (FR alpha) in the response of malignant pleural mesothelioma to pemetrexed-containing chemotherapy

作者：Nutt J E^*; Razak A R A; O'Toole K; Black F; Quinn A E; Calvert A H; Plummer E R; Lunec J

来源：British Journal of Cancer, 2010, 102(3): 553-560.

DOI：10.1038/sj.bjc.6605501

• Folate receptor alpha
• mesothelioma
• pemetrexed
• cell lines
• immunohistochemistry

BACKGROUND: The standard treatment of choice for malignant pleural mesothelioma is chemotherapy with pemetrexed and platinum, but the clinical outcome is poor. This study investigates the response to pemetrexed in a panel of eight mesothelioma cell lines and the clinical outcome for patients treated with pemetrexed in relation to folate receptor alpha (FR alpha).
METHODS: Cell lines were treated with pemetrexed to determine the concentration that reduced growth to 50% (GI(50)). FR alpha expression was determined by western blotting and that of FR alpha, reduced folate carrier (RFC) and proton-coupled folate transporter (PCFT) by real-time quantitative RT-PCR. Immunohistochemistry for FR alpha was carried out on 62 paraffin-embedded samples of mesothelioma from patients who were subsequently treated with pemetrexed.
RESULTS: A wide range of GI(50) values was obtained for the cell lines, H2452 cells being the most sensitive (GI(50) 22 nM) and RS5 cells having a GI(50) value greater than 10 mu M. No FR alpha protein was detected in any cell line, and there was no relationship between sensitivity and expression of folate transporters. FR alpha was detected in 39% of tumour samples, generally in a small percentage of cells. There was no correlation between the presence of FR alpha and the outcome of pemetrexed treatment, and no significant difference between histological subtypes.
CONCLUSION: Response to treatment with pemetrexed does not depend on the presence of FR alpha. British Journal of Cancer (2010) 102, 553-560. doi:10.1038/sj.bjc.6605501 www.bjcancer.

• 出版日期2010-2-2