Researchers from Johns Hopkins University School of Medicine and University Medical Center Utrecht in The Netherlands report in Modern Pathology that mutations in ATRX or DAXX and alternative telomere lengthening occur late in pancreatic neuroendocrine tumor development. Focusing on samples from patients with multiple endocrine neoplasia-1 syndrome — who are predisposed to developing pancreatic neuroendocrine tumor due to a MEN-1 mutation — the researchers examined ATRX and DAXX protein expression as well as telomere status in 109 lesions. They found that ATRX and/or DAXX expression loss correlated with the alternative telomere lengthening phenotype and that those events occurred only in patients with tumors larger than three centimeters.
Also in Modern Pathology, researchers led by Northwestern University Feinberg Medical School's Jian-Jun Wei report their analysis of MIR182 expression — a negative regulator of BRCA1 — in ovarian carcinoma. The researchers looked at MIR182 expression as well as the expression of its downstream target genes in patients with advanced ovarian cancer and found that MIR182 and HMGA2 were expressed at higher levels in high-grade serous ovarian carcinoma while BRCA1 expression was decreased. Further, the researchers say that of MIR182's targets, HMGA2 was associated with serous carcinomas, ascites, and a higher death rate. "Although we found a significant dysregulation of other selected genes in ovarian cancer, correlation between MIR182 and its target genes has not been established, indicating a complex regulation of these genes in ovarian cancer and lower sensitivity for semiquantitative immunohistochemical scores," Wei and his colleagues write.