In this work, we have evaluated resistance mechanisms to MAL-PDT developed by three BCC cell lines (ASZ, BSZ and CSZ), derived from mice on a ptch+/- background and with or without p53 expression, subjected to 10 cycles of PDT (10<sup>th</sup>G).
Keratinocyte skin cancer, comprising cutaneous squamous (cSCC) and basal cell carcinoma, is the most common malignancy in the United Kingdom.P53 is frequently mutated in cSCC. iASPP is a key inhibitor of p53 and NF-κB signaling pathways and has been documented as highly expressed in several types of human cancer.
Our finding suggest that certain clinicopathological and immunohistochemical variables, particularly p53 expression, may serve as indicators of BCC response to MAL-PDT, and thus facilitate the selection of patients who are most likely to benefit from this therapy.
Genital BCCs had a larger size (14.05 vs 8.92 mm, P = 0.014), more common presence of ulcers (61.3% vs 32.0%, P = 0.035), shorter epidermal p53 clone (0.33 vs 1.20 mm, P = 0.007), and high p53 expression levels.
In this study, we examined the immunohistochemical expression of p53 and cyclooxygenase-2 (COX-2) in 51 BCCs, nodular and infiltrative subtypes, with various Clark levels.
Here, to study the effect of the Smoothened inhibitor vismodegib on tumour clearance, we have used a Ptch1-Trp53 mouse model of BCC<sup>3</sup> and found that mice treated with vismodegib harbour quiescent residual tumours that regrow upon cessation of treatment.
Taken together, our data suggest that functional interactions between KIR and HLA modify risks of BCC and SCC and that KIR encoded by the B genes provides selective pressure for altered p53 in BCC tumors.
Pathway analysis identified several significantly overrepresented pathways including PPAR-γ signaling, TGF-β signaling and lipid metabolism, as well as confirmed the importance of SHH and p53 in the pathogenesis of BCC.
One work found higher rates of p53 and PTCH (both are tumor suppressor genes whose alterations are associated with BCC formation and frequency, but not biological behavior) abnormalities in post ionizing radiation BCCs.
The objective of this study was to investigate the presence of B-Raf mutations in sporadic BCCs as well as its correlation with the phenotype of microsatellite instability (MSI), the clinicopathological parameters of the tumours and p53 protein expression.
In 902 cases of basal cell carcinoma (BCC), 676 cases of squamous cell carcinoma (SCC) and 812 controls, no association was found between the TP53 polymorphism and risk of non-melanoma skin cancer [odds ratio (OR)(BCC) 0.98, 95% confidence interval (CI) 0.80-1.20; OR(SCC) 0.93, 95% CI 0.75-1.16].
We evaluated the effect of MDM2 SNP309 and its interaction with the p53Arg72Pro polymorphism on pigmentary phenotypes and skin cancer risk in a nested case-control study within the Nurses' Health Study (NHS) among 219 melanoma cases, 286 squamous cell carcinoma (SCC) cases, 300 basal cell carcinoma (BCC) cases, and 873 controls, and among controls from other studies.
Immunostaining with an antibody specific for mutated p53 revealed 63% fewer positive patches in BCCs of pTT-treated mice compared with controls (P < 0.01), and the number of Ki-67-positive cells was decreased by 56% (P < 0.01) in pTT-treated tumor-free epidermis and by 76% (P < 0.001) in BCC tumor nests (P < 0.001).
In the 22 non-aggressive tumors, less than 50% of cells showed positive staining. p53 immunoreactivity was significantly higher in aggressive BCCs than non-aggressive ones (x(2) test; p < 0.01).
Microdissection-based studies have also shown that different parts of individual BCC tumors can share a common p53 mutation yet differ with respect to additional alterations within the p53 gene, consistent with subclonal development within tumors.