Mutation of TP53 gene is involved in carcinogenesis of hepatic undifferentiated (embryonal) sarcoma of the adult, in contrast with Wnt or telomerase pathways: an immunohistochemical study of three cases with genomic relation in two cases.
On the other hand, p53 is a well-characterized tumor suppressor gene and p53 heterozygous mice develop sarcoma and other tumors starting from 12 months of age.
Abnormalities identified by immunohistochemistry included p21 immunonegativity (60%, 25%, 93%), which was most frequent in TE-GBM (P = .008), strong nuclear p53 staining (29%, 29%, 41%), strong membranous staining for epidermal growth factor receptor (EGFR) (21%, 63%, 19%), which was most frequent in E-GBM (P = .03), and an increased frequency of p27 immunonegativity in gliosarcomas (15% negative, 85% focal) compared with tumors without sarcoma (38% strongly positive) (P = .009).
A tumorigenic connection between the oncogene product Mdm2 and tumor suppressor p53 is generally accepted, but their possible clinical relevance has not yet been investigated sufficiently in soft tissue sarcoma.
Molecular assessment of clonality leads to the identification of a new germ line TP53 mutation associated with malignant cystosarcoma phyllodes and soft tissue sarcoma.
The mechanism responsible for tumour regression is dependent on the tumour type, with the main consequence of p53 restoration being apoptosis in lymphomas and suppression of cell growth with features of cellular senescence in sarcomas.
The mutation status of TP53 and expression of MDM2, TP53, and their genetic variants SNP309 and R72P (Arg72Pro) were investigated in 125 sarcoma patient samples and 18 sarcoma cell lines.
Mutation of the p53 tumor suppressor gene, with resultant overexpression of p53 protein, frequently occurs in human soft tissue sarcomas, supporting the role of p53 mutations in the pathogenesis of soft tissue sarcoma and the possible usefulness of p53 immunolocalization as a screening method for p53 mutations.
APC mutated (Min) mice develop large and small bowel adenomas, a small proportion of which, in time, become malignant. p53 deficient mice develop predominantly lymphoma and sarcoma.