Since all three glutathione S-transferase isoenzyme classes contribute to the resistance to antineoplastic drugs, the altered glutathione S-transferase isoenzyme pattern and the decrease of glutathione S-transferase activity may play a role in the high inherent drug sensitivity of human testicular germ cell tumors.
A diverse group of gonadal and extragonadal human germ cell tumors (GCT) and GCT-derived cell lines was examined for the presence of an i(12p) marker chromosome and/or other abnormalities involving chromosome 12, especially 12p, by bicolor double fluorescence in situ hybridization (FISH).
Cytogenetic analysis of germ cell tumors (GCTs) has identified i(12p) as a specific cytogenetic abnormality identified in more than 80% of GCTs, present in all histologies, in primary and metastatic lesions, in testicular and extragonadal presentations, and in ovarian and sex cord stromal tumors.
Clonal relationship between the teratoma and rhabdomyosarcoma of the germ cell tumor was established by the presence in both of i(12p), the characteristic marker of germ cell tumors.
There were significant differences in oncogene expression between seminomas and nonseminomas with c-kit being expressed in 24 of 30 (80%) seminomas but in only 3 of 40 (7%) nonseminomatous tumors (P = 0.0001, chi 2 test) and hst-1 being expressed in 24 of 38 (63%) nonseminomas but only 1 of 24 (4%) of seminomas (P = 0.0001, chi 2 test), demonstrating an inverse relationship in the expression pattern of these 2 oncogenes in human testicular germ cell tumors.
No gross alterations in the c-kit, hst-1, and int-2 loci were found at the DNA level and no int-2 mRNA expression was detected in any of the germ cell tumors examined.
No gross alterations in the c-kit, hst-1, and int-2 loci were found at the DNA level and no int-2 mRNA expression was detected in any of the germ cell tumors examined.
In comparison with normal DNA, tumour DNA of a total of eight patients (seven with germ cell neoplasm and one with testicular lymphoma) showed increased dosages of KRAS2, PDGFA, EGFR, MET and PDGFB.
In comparison with normal DNA, tumour DNA of a total of eight patients (seven with germ cell neoplasm and one with testicular lymphoma) showed increased dosages of KRAS2, PDGFA, EGFR, MET and PDGFB.
We have studied 31 male germ cell tumors (GCTs) for probable mutations in codons 12, 13, and 61 of HRAS, KRAS, and NRAS oncogenes using the polymerase chain reaction.
We have studied 31 male germ cell tumors (GCTs) for probable mutations in codons 12, 13, and 61 of HRAS, KRAS, and NRAS oncogenes using the polymerase chain reaction.
No geographic incidence variation was detected for -7 and +21 in ANLL; +8 in MDS; 6q- and +8 in ALL; +12 in chronic lymphocytic leukemia; 6q- in non-Hodgkin's lymphoma (NHL); t(8;14) in Burkitt's lymphoma; t(11;22) in Ewing's sarcoma; i(12p) in germ cell tumors; 1p- in neuroblastoma; structural abnormalities of 3q, 8q, and 9p in PAS; or 3p- in renal cell carcinoma.
This report indicates that further investigation is necessary to establish the role of the i(12p) marker in the pathogenesis of germ cell tumors also in females.
With diagnostic and possibly prognostic importance in germ cell tumors in males, the high frequency of i(12p) in our series of studies and in those of others indicates that it probably occurs as a very early defect in the development of these tumors.
Restriction fragment length polymorphism analysis is used to demonstrate that formation of the i(12p) chromosome, characteristic of testicular germ cell tumors, does not lead to loss of heterozygosity of various loci on the q arm of chromosome 12.