We investigated the role of CDKN2A deletion in urothelial carcinogenesis, as a function of FGFR3 mutation status, a marker for one of the two pathways of bladder tumour progression, the Ta pathway.
Our data indicate that genetic variants in CDKN2A, and possibly nearby genes, may be associated with ESCC and several other tumours, further highlighting the importance of 9p21.3 genetic variants in carcinogenesis.
In this aspect, the potential role of the CDKN2 gene at 9p21-p22 in ovarian carcinogenesis was assessed in an extended panel of ovarian tumors, 11 human ovarian carcinoma cell lines, and 1 cervical tumor cell line.
Our data indicate that in spite of low or absent p16 expression, genetic alterations of the p16 and Rb tumour suppressor genes are rare in endometrial carcinogenesis.
These results suggested that mutation of the p16/CDKN2 gene was a common factor in the development of human MMMs and ACCs, while this gene may be correlated with development and/or progression of a subtype and play a role in the oncogenesis of these cancers.
We hypothesize that the presence of the fourth product, pALT(INK4a/b) of the INK4a/b locus in the naked mole rat, contributes to the increased resistance to tumorigenesis of this species.
Although the number of cases we analyzed was not large, alterations identified in the Rb, p53, p16, p15 and p14 genes are of significance and might be associated with tumorigenesis in NK cell neoplasms.
The CDKN2A locus is frequently inactivated in urothelial cell carcinoma (UCC), yet how this alteration contributes to bladder tumorigenesis is not known.
Our frequent detection (80%) of p16 and p15 gene deletions might suggest that these deletions are closely related to carcinogenesis in primary malignant lymphoma of the brain.
From these data we conclude that the occurrence of CDKN2 (p16/MTS1) mutation in primary breast cancer is a rare event and is not likely to be involved in human breast tumour carcinogenesis and progression.
Our results suggest that the MTS1 gene is not mutated with increased frequency in primary breast tumors, and thus may not play a major role in breast carcinogenesis.
As combinations of genetic and/or epigenetic alterations occurring during salivary gland carcinogenesis are largely unknown, we here analyzed 36 salivary gland carcinomas (SGCs) for changes in INK4a/ARF, RB1, p21, p27, PTEN, p53, MDM2 and O6-MGMT genes using methylation specific PCR (MSP), loss of heterozygosity (LOH) assays and mutational analysis with immunohistochemistry (IHC), as well as histone H3 and H4 acetylation status.
Eleven GCAs occurring in 7 men and 4 women ranging in age from 46 to 75 years were investigated for genetic alterations of known significance in glial tumorigenesis, including LOH at 1p, 9p, 10q, 17p, and 19q, point mutations of TP53, deletions of p16(CDKN2A) and p14ARF, as well as EGFR amplifications.
Deletion was detected as frequently in stage I tumours as in late-stage tumours, suggesting that p16 deletion is a relatively early event in urothelial tumorigenesis.
The creation of an aberrant initiation site in the 5' UTR may have an important role in carcinogenesis in a small percentage of families; however, mutations in the CDKN2A promoter appear to have a limited role in predisposition to melanoma.