Exome sequencing of a colorectal cancer family reveals shared mutation pattern and predisposition circuitry along tumor pathways

The molecular basis of cancer and cancer multiple phenotypes are not yet fully understood. Next Generation Sequencing promises new insight into the role of genetic interactions in shaping the complexity of cancer. Aiming to outline the differences in mutation patterns between familial colorectal cancer cases and controls we analyzed whole exomes of cancer tissues and control samples from an extended colorectal cancer pedigree, providing one of the first data sets of exome sequencing of cancer in an African population against a background of large effective size typically with excess of variants. Tumors showed hMSH2 loss of function SNV consistent with Lynch syndrome. Sets of genes harboring insertions-deletions in tumor tissues revealed, however, significant GO enrichment, a feature that was not seen in control samples, suggesting that ordered insertions-deletions are central to tumorigenesis in this type of cancer. Network analysis identified multiple hub genes of centrality. ELAVL1/HuR showed remarkable centrality, interacting specially with genes harboring non-synonymous SNVs thus reinforcing the proposition of targeted mutagenesis in cancer pathways. A likely explanation to such mutation pattern is DNA/RNA editing, suggested here by nucleotide transition-to-transversion ratio that significantly departed from expected values (p-value 5e-6). NFKB1 also showed significant centrality along with ELAVL1, raising the suspicion of viral etiology given the known interaction between oncogenic viruses and these proteins.

Colorectal carcinoma associated with schistosomiasis: a possible causal relationship

The association between schistosomiasis and colorectal malignancy has long been suggested in the literature, but it is not uniformly accepted. In the Far East, considerable evidence supports an etiological link between Schistosoma japonicum and colorectal cancer. However, the available data regarding the role of Schistosoma mansoni in colorectal carcinogenesis are conflicting and most often do not show causality. We report on a patient with sigmoid colonic cancer coexisting with schistosomiasis, and we provide a comprehensive review of the literature regarding the epidemiology and pathobiology of this association.

Paediatric gastrointestinal endoscopy: experience in a Sudanese university hospital

We investigated the indications for and findings of gastrointestinal (GI) endoscopy in all children < or = 16 years old referred for the procedure to the endoscopy unit at Soba University Hospital, Khartoum from January 2004 to January 2006. Thus 113 children were enrolled; 73% underwent upper GI endoscopy, 27% lower GI endoscopy (15% colonoscopy, 12% flexible sigmoidoscopy). Indications for upper GI endoscopy included haematemesis (24%), portal hypertension (21%), abdominal pain (16%) and vomiting (15%). Diagnoses included oesophageal varices (16%), gastritis (7%) and hiatus hernia (6%). Indications for lower GI endoscopy included rectal bleeding (87%), diarrhoea (19%) and anaemia (10%).