title: Genomic aberrations in an African American colorectal cancer cohort reveals a MSI-specific profile and chromosome X amplification in male patients.
abstract: OBJECTIVE
  DNA aberrations that cause colorectal cancer (CRC) occur in multiple steps that involve microsatellite instability (MSI) and chromosomal instability (CIN). Herein, we studied CRCs from AA patients for their CIN and MSI status.
  
  
  METHODS
  Array CGH was performed on 30 AA colon tumors. The MSI status was established. The CGH data from AA were compared to published lists of 41 TSG and oncogenes in Caucasians and 68 cancer genes, proposed via systematic sequencing for somatic mutations in colon and breast tumors. The patient-by-patient CGH profiles were organized into a maximum parsimony cladogram to give insights into the tumors' aberrations lineage.
  
  
  RESULTS
  The CGH analysis revealed that CIN was independent of age, gender, stage or location. However, both the number and nature of aberrations seem to depend on the MSI status. MSI-H tumors clustered together in the cladogram. The chromosomes with the highest rates of CGH aberrations were 3, 5, 7, 8, 20 and X. Chromosome X was primarily amplified in male patients. A comparison with Caucasians revealed an overall similar aberration profile with few exceptions for the following genes; THRB, RAF1, LPL, DCC, XIST, PCNT, STS and genes on the 20q12-q13 cytoband. Among the 68 CAN genes, all showed some level of alteration in our cohort.
  
  
  CONCLUSIONS
  Chromosome X amplification in male patients with CRC merits follow-up. The observed CIN may play a distinctive role in CRC in AAs. The clustering of MSI-H tumors in global CGH data analysis suggests that chromosomal aberrations are not random.
authors.affiliation: Department of Medicine and Cancer Center, College of Medicine, Department of Pathology, Howard University, Washington, D.C., United States of America.
authors.forename: Hassan
authors.initials: H
authors.lastname: Brim
authors.forename: Edward
authors.initials: E
authors.lastname: Lee
authors.forename: Mones S
authors.initials: MS
authors.lastname: Abu-Asab
authors.forename: Mohamed
authors.initials: M
authors.lastname: Chaouchi
authors.forename: Hadi
authors.initials: H
authors.lastname: Razjouyan
authors.forename: Hassanzadeh
authors.initials: H
authors.lastname: Namin
authors.forename: Ajay
authors.initials: A
authors.lastname: Goel
authors.forename: Alejandro A
authors.initials: AA
authors.lastname: Schäffer
authors.forename: Hassan
authors.initials: H
authors.lastname: Ashktorab
mesh_terms: D001741:Black or African American / Q000235:genetics*; D000368:Aged; D002869:Chromosome Aberrations; D002890:Chromosomes, Human, Pair 20 / Q000235:genetics; D041321:Chromosomes, Human, X / Q000235:genetics*; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D055028:Comparative Genomic Hybridization; D003710:Demography; D005260:Female; D005784:Gene Amplification / Q000235:genetics*; D052138:Genes, Neoplasm / Q000235:genetics; D015894:Genome, Human / Q000235:genetics*; D006801:Humans; D008297:Male; D053842:Microsatellite Instability; D008875:Middle Aged; D010802:Phylogeny; D044465:White People / Q000235:genetics