High-resolution melting analysis (HRMA) provides a valid approach to efficiently detect DNA genetic and somatic mutations. In this study, HRMA was used for the screening of 116 colorectal cancers (CRCs) to detect hot-spot mutations in the KRAS and BRAF oncogenes. Mutational hot spots on the PIK3CA gene, exons 9 and 20, were also screened. Direct sequencing was used to confirm and characterize HRMA results. HRMA revealed abnormal melting profiles in 65 CRCs (56.0%), 16 of them harboring mutations in 2 different genes simultaneously. The frequency of mutations was 17.2% for PIK3CA (11.2% in exon 9 and 6.0% in exon 20), 43.1% for KRAS exon 2, and 9.5% in exon 15 of the BRAF gene. We found a significant association between PIK3CA and KRAS mutations (P = .008), whereas KRAS and BRAF mutations were mutually exclusive (P = .001). This report describes a novel approach for the detection of PIK3CA somatic mutations by HRMA.

Circulating Tumor Cells (CTCs) represent a “liquid biopsy” of the tumor potentially allowing real-time monitoring of cancer biology and therapies in individual patients.The purpose of the study was to explore the applicability of a protocol for the molecular characterization of single CTCs by Next Generation Sequencing (NGS) in order to investigate cell heterogeneity and provide a tool for a personalized medicine approach.CTCs were enriched and enumerated by CellSearch in blood from four metastatic breast cancer patients and singularly isolated by DEPArray. Upon whole genome amplification 3–5 single CTCs per patient were analyzed by NGS for 50 cancer-related genes.We found 51 sequence variants in 25 genes. We observed inter- and intra-patient heterogeneity in the mutational status of CTCs.The highest number of somatic deleterious mutations was found in the gene TP53, whose mutation is associated with adverse prognosis in breast cancer.The discordance between the mutational status of the primary tumor and CTCs observed in 3 patients suggests that, in advanced stages of cancer, CTC characteristics are more closely linked to the dynamic modifications of the disease status.In one patient the mutational profiles of CTCs before and during treatment shared only few sequence variants.This study supports the applicability of a non-invasive approach based on the liquid biopsy in metastatic breast cancer patients which, in perspective, should allow investigating the clonal evolution of the tumor for the development of new therapeutic strategies in precision medicine.

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Background: The presence of sequence variants in miRNA genes may influence their processing, expression and binding to target mRNAs. Since single miRNA can have a large number of potential mRNA targets, even minor variations in its expression can have influences on hundreds of putative mRNAs. Methods: Here, we evaluated 101 paired samples (cancer and normal tissues) from non-small cell lung carcinoma (NSCLC) patients to study the genotype distribution of single nucleotide polymorphisms (SNPs) in miR-146a (rs2910164 C-G), miR-149 (rs2292832 C-T), miR-196a2 (rs11614913 C-T) and miR-499 (rs3746444 G-A) and their influence on the expression of respective miRNAs.Results: Relative expression of miR-146a, miR-149 and miR-499 were comparable in NSCLC and in paired control tissues. On the contrary, we clearly detected a significant increase (p-0.001) of miR-196a2 expression in NSCLC. In particular we found a significant association between miR196a2 CC genotype and high expression, whereas TT genotype showed a very low expression in comparison to both CT (p-0.005) and CC patients (p-0.01). We did not find any association between miR-149, miR-196a2 and miR-499 genotype and risk of NSCLC. Conversely, CG genotype of miR-146a appeared associated to an increased risk for NSCLC (ps0.042 and 1.77 OR). Conclusions:Our results seem to demonstrate that sequence variants of miR-196a2 can have an influence on its expression, while miR-146a can have a role in increasing the risk of NSCLC.

These results indicate that denosumab induces a partial maturation towards the osteoblastic phenotype of the neoplastic cells of GCTB, with production of fibrous and osteoid matrix, but with minor immunophenotypical changes. Finally, we first report an antiangiogenic activity of denosumab in GCTB, possibly mediated by a RANKL-dependent pathway.