Prognostic relevance of aberrant DNA methylation in g1 and g2 pancreatic neuroendocrine tumors.

Background/aims: The occurrence and clinical relevance of DNA hypermethylation and global hypomethylation in pancreatic neuroendocrine tumours (PanNETs) are still unknown. We evaluated the frequency of both epigenetic alterations in PanNETs to assess the relationship between methylation profiles and chromosomal instability, tumour phenotypes and prognosis.

Methods: In a well-characterized series of 56 sporadic G1 and G2 PanNETs, methylation-sensitive multiple ligation-dependent probe amplification was performed to assess hypermethylayion of 33 genes and copy number alterations (CNAs) of 53 chromosomal regions.

Pyrosequencing for EGFR mutation detection: diagnostic accuracy and clinical implications.

EGFR-activating mutations predict responsiveness to EGFR tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC) patients. Mutation screening is crucial to support therapeutic decisions and is commonly conducted using dideoxy sequencing, although its sensitivity is suboptimal in clinical settings. To evaluate the diagnostic performance of pyrosequencing and dideoxy sequencing, we examined EGFR mutation status in a retrospective cohort of 53 patients with NSCLCs clinically selected for TKI therapy and whose clinical outcome was available.

Diagnostic utility of MS-MLPA in DNA methylation profiling of adenocarcinomas and neuroendocrine carcinomas of the colon-rectum.

Methylation-specific multiple ligation-dependent probe amplification (MS-MLPA) is a fast, new, inexpensive method that has rarely been exploited in DNA methylation profiling of colorectal cancers (CRCs). The aim of this study was to test the diagnostic utility of MS-MLPA to evaluate the methylation status of 34 genes in normal colonic mucosa samples and in a well-characterized series of 83 adenocarcinomas and 21 neuroendocrine carcinomas of colon-rectum. Two commercial MS-MLPA kits (SALSA MS-MLPA ME001-C1 Tumor suppressor-1 Kit and SALSA MS-MLPA ME002-B1 Tumor suppressor-2 Kit) were used to perform promoter methylation analysis on formalin-fixed and paraffin-embedded tissues.