Here we report that PIPs, predominantly <3,000 p53 immunopositive cells in size, within normal chronically exposed skin contain mutations in multiple genes that are mutated in cutaneous squamous cell cancers.
Repression of E6 and E7 oncogenes results in restoration of p53 and pRb suppressor pathways and induced apoptosis in HPV16-positive oropharyngeal squamous cell cancer cell lines.
We hypothesized that the MDM2 G/G genotype may be associated with worse survival outcomes in lung cancer, especially in squamous cell cancers where p53 abnormalities are more common.
Yet, comprehensive analyses of LOH patterns at these chromosomal sites and of p53 alterations are not reported for histologically normal bronchial epithelium, high-grade bronchial dysplasia, and SCC present in the same pulmonary resections.
We undertook this study to correlate the expression of p53 and eIF4E in the tumors and surgical margins of squamous cell cancers of the larynx and to determine their prognostic value.
We immunohistochemically examined the nuclear accumulation of mutant p53 and the cytoplasmic overexpression of bcl-2 proteins in 76 patients with locally advanced inoperable squamous cell cancer of the head and neck area.
Sequencing analysis of RNA and DNA of exons 1 through 11 shows p53 gene alterations to be present in almost 100% of head and neck squamous cell cancers.
The recombinant wild-type p53 adenovirus has been proven effective against the growth of human head and neck squamous cell cancer (SCCHN) cell lines iir vitro and in a nude mouse model.
By microdissection, sequence analysis of the p53 gene, and analysis of loss of heterozygosity (LOH) at the site of this gene, we have now extended previous data to ascertain whether these p53 patches are precursors of simultaneously present squamous cell cancer or its morphologically recognized precancerous stages (dysplasia, carcinoma in situ).
The polymerase chain reaction and highly informative microsatellite markers were used to compare DNA from matched sets of 63 head and neck squamous cell cancers and normal tissue for LOH at the p53 and Rb loci.
Although abnormalities of the p53 tumor suppressor oncogene system are being detected in many human cancers, the frequency and prognostic significance of such events in squamous cell cancer of the head and neck remain unknown.