A molecular signature for oncogenic BRAF in human colon cancer cells is revealed by microarray analysis.

Sporadic colorectal cancer develops through a number of functional mutations. Key events are mutually exclusive mutations in BRAF or RAS oncogenes. Signatures for BRAF oncogene have been revealed in melanoma. In a previous study we have reported a molecular signature for HRAS and KRAS mutations in colorectal cell lines that also showed an EMT phenotype for HRAS. In this study we report a molecular profile for a BRAF oncogenic mutation BRAFV600E in colon using the Illumina 45,000 gene microarray. Key differentially expressed genes have been identified from the array analysis further verified by qPCR analysis. Ingenuity pathway analysis such as microsatellite instability, kinase signalling, apoptosis, WNT and Integrin signalling is presented. MutBRAF transforms cells through cross talk with developmental pathways Hedgehog and Wnt, as well as by deregulation of colorectal cancer related kinase pathways, like PI3K. Differential gene expression of BRAFV600E in colon as compared to those associated with RAS oncogenes is presented, as well as similarities and differences between oncogenic BRAF signatures in colon as compared to thyroid and melanoma are highlighted. Novel selected genes/pathways are validated in cell lines and clinical samples bearing BRAFV600E and may serve as markers/targets for personalised diagnosis/therapy/resistance of colorectal cancer.

Transient and chronic neutropenias detected in children with different viral and bacterial infections.

AIM: The aim of the study was to identify the relationship of acquired neutropenias with infections in childhood and to assess their course, complications, short and long-term outcome. METHOD: During a two-year period, all children admitted to the pediatric ward with neutropenia were investigated for underlying infections with indices of infection, cultures of body fluids and serological tests. RESULTS: Sixty-seven previously healthy children, aged (median, 25-75%) 0.7 years (0.2-1.5), were identified with neutropenia (frequency: 2.0%). An infectious agent was identified in 34/67 cases (50.7%) (viral infection: n=24, bacterial: n=10). In 50/67 (74.6%) children, neutropenia recovered within 2 months (transient neutropenia, TN), while in 17/67 (25.4%) of them it persisted for more than two months. Two years after diagnosis 50/67 children (74.6%) accepted to be reassessed. Of these children, 8/50 (16%) remained neutropenic (neutropenic children, NC), while 42/50 had recovered completely. CONCLUSION: Neutropenia during childhood is usually transient, often following viral and common bacterial infections, does not present serious complications and in the majority, it resolves spontaneously. However, in a significant percentage of patients, neutropenia is discovered during the course of an infection, on a ground of a preceding chronic neutropenic status.