Immunoreactivity to p53 was also observed in the majority of keratoacanthomas and solar keratoses, but was confirmed to areas of dysplastic basal epithelium.
While there was a highly significant trend in the proportion of p53 oncoprotein-positive lesions from keratoacanthomas to poorly differentiated squamous cell carcinomas (chi 2 = 17.13, df = 1, exact P = 0.00003), p53 expression was inadequate for distinguishing keratoacanthoma from well-differentiated squamous cell carcinoma (chi 2 = 2.55, df = 1, exact P = 0.18; corresponding to a sensitivity of 0.84 and a specificity of only 0.36).
The karyotype of the keratoacanthoma was more complex: 46,XX,der(2)(2pter----2p13::2p11----cen----2q37: :5q33----5qter),der(2) (:2p13----cen----2q37::6q23----6qter),der(5)t(2; 7;5)(q37;q11;q33),der(6) (6pter----cen----6q23::2p13----2pter),der(7)t(2; 7;5)(q37;q11;q33), del(13)(q11q14).
The karyotype of the keratoacanthoma was more complex: 46,XX,der(2)(2pter----2p13::2p11----cen----2q37: :5q33----5qter),der(2) (:2p13----cen----2q37::6q23----6qter),der(5)t(2; 7;5)(q37;q11;q33),der(6) (6pter----cen----6q23::2p13----2pter),der(7)t(2; 7;5)(q37;q11;q33), del(13)(q11q14).
The degree and pattern of staining suggest a loss of bcl-2 expression with tumor maturity in keratoacanthoma and a possible role in their ultimate involution.
Mutations of the p53 gene were detected in seven of 23 SCCs (30%), three of 25 BCCs (12%), and none in all cases of Bowen's disease, solar keratosis, or keratoacanthoma.
Here we studied the expression of SKALP/elafin in several types of epidermal tumors (basal cell carcinoma, squamous cell carcinoma, Bowen's disease, actinic keratosis, and keratoacanthoma).
There was no statistically significant trend in tumour staining from keratoacanthoma through decreasing grades of differentiation of squamous cell carcinoma. nm23 product expression does not appear to correlate with differentiation, itself an indicator of metastatic potential, in this system of human squamous cell neoplasms.(ABSTRACT TRUNCATED AT 250 WORDS)
Classical KA showed a PCNA staining pattern located predominantly around the basal cell layers, in contrast to a relatively diffuse staining pattern seen in WDSCC.
Since mutations of the p53 tumor suppressor gene are found frequently in cutaneous squamous cell carcinomas, we hypothesized that p53 mutations might contribute to the development of keratoacanthomas.
Three of the 12 additional patients diagnosed with a KA and a colorectal carcinoma had at least one tumor that had MIN at two or more loci, and one of these patients had HNPCC: A 2-base pair somatic deletion in exon 3 of the hMSH2 gene was identified in one of the MIN+ KAs.
Expression of p53 oncoprotein in immunohistochemical staining and its correlation to gene mutations in DNA extracted from KAs and tested in single-strand conformational polymorphism (SSCP) analysis and direct sequencing.
There was no difference between KAs and SCCs in expression of lymphotoxin-alpha, IL-2, interferon-gamma (IFN-gamma), IL-13, transforming growth factor-beta (TGF-beta), or the pro-inflammatory cytokines IL-8 or tumour necrosis factor-alpha (TNF-alpha).
There was no difference between KAs and SCCs in expression of lymphotoxin-alpha, IL-2, interferon-gamma (IFN-gamma), IL-13, transforming growth factor-beta (TGF-beta), or the pro-inflammatory cytokines IL-8 or tumour necrosis factor-alpha (TNF-alpha).
There was no difference between KAs and SCCs in expression of lymphotoxin-alpha, IL-2, interferon-gamma (IFN-gamma), IL-13, transforming growth factor-beta (TGF-beta), or the pro-inflammatory cytokines IL-8 or tumour necrosis factor-alpha (TNF-alpha).
A series of 120 biopsies from benign (verruca vulgaris and keratoacanthoma), premalignant (actinic keratosis and extragenital Bowen's disease) and malignant (squamous cell carcinoma) skin lesions were studied immunohistochemically for the expression of cell-cycle proteins p53, p21 (WAF-1), PCNA and Ki-67.
A series of 120 biopsies from benign (verruca vulgaris and keratoacanthoma), premalignant (actinic keratosis and extragenital Bowen's disease) and malignant (squamous cell carcinoma) skin lesions were studied immunohistochemically for the expression of cell-cycle proteins p53, p21 (WAF-1), PCNA and Ki-67.
Cutaneous (eight sebaceous adenomas, one sebaceous carcinoma and one keratoacanthoma) and internal tumors (four colonic adenocarcinomas, two endometrial carcinomas, two transitional cell carcinomas of renal pelvis and ureter, one adenocarcinoma of the small bowel, one ovarian carcinoma and one colonic tubular adenoma) were obtained from six patients with MTS and were subjected to microsatellite instability (MI) analysis, and to immunostaining for MLH-1 and MSH-2.
Telomerase activity, COX-2, and p53 expression provide evidence that keratoacanthoma and squamous cell carcinoma are indeed distinct entities and also help in discriminating these two lesions, which closely resemble each other on conventional morphology.
Telomerase activity, COX-2, and p53 expression provide evidence that keratoacanthoma and squamous cell carcinoma are indeed distinct entities and also help in discriminating these two lesions, which closely resemble each other on conventional morphology.