Methylated estrogen receptor alpha in tumors and sera of melanoma patients

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Background: The mechanisms regulating the variable expression of estrogen receptor alpha (ER-α) in melanoma are unknown. Silencing of ER-α expression in melanoma may be regulated by the hypermethylation of promoter region CpG islands. To determine the significance of ER-α hypermethylation-induced transcription silencing in melanoma progression, we assessed hypermethylation of ER-α DNA in primary tumors, metastatic tumors, and sera of AJCC stage I-IV melanoma patients. Methods: The methylation status of theER-α DNA promoter region in tumor (n = 107) and sera (n = 119) from AJCC stage I-IV melanoma patients was examined by methylation-specific PCR (MSP) and capillary array electrophoresis (CAE). To determine the significance of free circulating hypermethylated ER-α DNA, we assessed the therapeutic response, progression-free and overall survival among AJCC stage IV melanoma patients receiving biochemotherapy. Results: The frequency of ER-α DNA methylation in AJCC stage I, II, and III primary melanomas was 36% (4 of 11), 26% (5 of 19), and 35% (8 of 23), respectively. The frequency of methylated ER-α DNA detected in stage III and IV metastatic melanomas was 42% (8 of 19) and 86% (30 of 35), respectively. ER-α DNA was methylated in 38 of 54 (70%) metastatic tumors, a more than two-fold increase compared to primaries (p = 0.0003). In the analysis of 109 melanoma patients’ sera, the frequency of methylated ER-α DNA in AJCC stage I, II, III, and IV was 10% (2 of 20), 15% (3 of 20), and 26% (5 of 19), and 32% (16 of 50), respectively. The frequency of methylated ER-α DNA detected in stage III/IV was significantly higher than in stage I/II (p=0.034). In a multivariate analysis, circulating hypermethylated ER-α DNA was the only independent factor predicting progression-free (risk ratio 2.64, 95% CI 1.36–5.13, p = 0.004) and overall survival (risk ratio 2.31, 95% confidence interval 1.41–5.58, p = 0.003) among stage IV patients receiving biochemotherapy. Conclusion: Hypermethylation of ER-α DNA in primary and metastatic melanoma tumors and serum is a significant factor in melanoma progression. The detection of methylated serum ER-α DNA predicts poor response to systemic therapy and is an unfavorable prognostic factor in advanced melanoma.

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Quality control issues in the management of colon cancer patients

Quality assurance in colon cancer demands a multidisciplinary effort involving general practitioners, surgeons, radiologists, gastroenterologists, medical oncologists, and pathologists, among others. Maximal improvements in survival will result when colon cancer screening, diagnosis, staging, treatment and surveillance are optimized. We seek to identify those issues most relevant to the quality of care we provide our colon cancer patients.