title: Reviews of chromosome studies in urological tumors. III. Cytogenetics and genes in testicular tumors.
abstract: OBJECTIVE
  We reviewed available cytogenetic and molecular findings in testicular germ cell tumors, and their possible application to clinical, pathological and basic parameters.
  
  
  METHODS
  Findings in the literature on testicular germ cell tumors as well as those from our laboratory were summarized, including a listing of the cytogenetic findings on testicular germ cell tumors to date with some illustrations.
  
  
  RESULTS
  Testicular germ cell tumors are characterized in most cases by the presence of an i(12p) isochromosome. In tumors without such an abnormal chromosome studies using fluorescence in situ hybridization and molecular approaches have demonstrated either masking of the i(12p) or the presence of extra 12p sequences in the karyotype. Although testicular germ cell tumors are often associated with chromosome changes in addition to the i(12p), no other specifically recurrent structural chromosome changes have been found. Based on the cytogenetic and molecular findings in testicular germ cell tumors, a hypothetical scheme for the genetic events leading to these tumors is presented.
  
  
  CONCLUSIONS
  The genetic events leading to genesis of testicular germ cell tumors in men appear to be related to aneuploidization followed by the formation of an i(12p) isochromosome, the latter characterizing the preponderant number of testicular germ cell tumors. The exact role of the i(12p) isochromosome in testicular germ cell tumor pathogenesis remains to be determined, as is true of the genes involved in or affected by these tumors. Based on presently available information, a hypothetical pathogenetic and oncogenetic model for the development of testicular germ cell tumors is presented.
authors.affiliation: Southwest Biomedical Research Institute and Genetrix, Inc., Scottsdale, Arizona, USA.
authors.forename: A A
authors.initials: AA
authors.lastname: Sandberg
authors.forename: A M
authors.initials: AM
authors.lastname: Meloni
authors.forename: R F
authors.initials: RF
authors.lastname: Suijkerbuijk
mesh_terms: D000782:Aneuploidy; D014408:Biomarkers, Tumor; D002874:Chromosome Mapping; D002881:Chromosomes, Human, Pair 12; D018450:Disease Progression; D016147:Genes, Tumor Suppressor; D018392:Genomic Imprinting; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D018404:Isochromosomes / Q000235:genetics*; D007621:Karyotyping; D008297:Male; D009373:Neoplasms, Germ Cell and Embryonal / Q000235:genetics*; D011519:Proto-Oncogenes; D013736:Testicular Neoplasms / Q000235:genetics*
chemical_list: D014408:Biomarkers, Tumor