Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04637 (p53)
 77,613 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oral carcinomas frequently contain human papilloma virus (HPV)-16/18. As p53 is degraded through interaction with HPV-16/18 products (E6/E7), p53 dysfunction may contribute to oral carcinogenesis. Furthermore, epidemiological studies suggest that smoking history may be critical for oral carcinogenesis. To delineate the involvement of HPV-16 infection and carcinogen in oral carcinogenesis, Park et al have established a multistep oral carcinogenesis model. Overexpression of p53 altered the expression of Fas antigen (Fas-R), Bax and Bcl-2; however, it remains unclear how the loss of p53 modifies the expression of these molecules. Using the multistep oral carcinogenesis model, we analyzed how the loss of p53 and carcinogen modified the expression of these molecules and their role in the development of resistance to apoptosis of oral carcinomas. The HOK-16B cell line was immortalized by HPV-16 transfection of normal human oral keratinocytes (NHOK). HOK-16B-BaP and HOK-16B-BaP-T1 were established from HOK-16B following short-term and long-term stimulation with the chemical carcinogen, benzo(a)pyrene, respectively. The malignant phenotype develops in sequence from HOK-16B, HOK-16B-BaP and HOK-16B-BaP-T1. The expression of apoptosis-related molecules was examined by Western blot analysis or by flow cytometry. Fas-mediated cytotoxicity was assessed using CH-11, an agonistic anti-Fas-R IgM monoclonal antibody. The apoptosis-related molecules examined were the Fas-R, Bcl-2, Bax, and Fas-associated phosphatase 1 (FAP-1). Downregulation of Fas-R and upregulation of Bcl-2 in HOK-16B-BaP were observed in HOK-16B-BaP and HOK-16B-BaPT1. Bax was downregulated in HOK-16B, HOK-16B-BaP and HOK-16B-BaP-T1. The expression of FAP-1 was increased with progression towards malignancy. NHOK and HOK-16B were relatively sensitive to CH-11, whereas HOK-BaP and HOK-BaP-T1 were resistant to CH-11. Treatment of HOK-16B-BaP with antisense bcl-2 oligonucleotide rendered the cells more sensitive to CH-11-induced apoptosis. These data demonstrate that both the loss of p53 and carcinogen stimulation are associated with altered expression of Fas-R, Bcl-2 and FAP-1, although the loss of p53 is sufficient for altered expression of Bax. Thus, both HPV infection and smoking contribute to acquisition of anti-apoptotic characteristics by oral carcinomas.
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PMID:Both HPV and carcinogen contribute to the development of resistance to apoptosis during oral carcinogenesis. 1067 94

Oral carcinoma (OSCC) is one of the most important causes of cancer death worldwide. OSCC cell lines and preclinical rodent models are crucial to addressing the mechanisms of OSCC and helping the development of new therapeutic strategies and interventions. The establishment of murine OSCC cell lines and syngeneic models are necessary to allow concordant investigation of both in vitro and in vivo pathogenesis. In this study, we established two murine tongue squamous cell carcinoma cell lines, designated MTCQ1 and MTCQ2, from 4NQO-induced OSCC using C57BL/6 mice. These cell lines express a variety of epithelial markers but produce only a tiny amount of E-cadherin. The expression of mesenchymal and stemness regulators are evident, and this is associated with the high mobility in these cell lines. MTCQ1 also shows high Ki67 and PCNA expression, and complicated alterations in p53 expression, which may underlie its high clonogenic potential and rapid orthotopic tumor induction. Using the MTCQ1 cell subclone tagged with GFP (MTCQ1-GFP), extensive neck nodal metastasis and lung metastasis were identified by immunostaining and fluorescence imaging. Inhibition of oncogenic miRNAs, particularly miR-134, was able to attenuate the oncogenicity of MTCQ1-GFP. Cisplatin treatment inhibited both in vitro and in vivo growth of MTCQ1-GFP, and it was found to decrease miR-134 expression in this subclone. The anti-PD-L1 treatment enhanced the inhibitory effects of cisplatin against tumorigenesis. This syngeneic preclinical model should help provide valuable mechanistic insights into OSCC, as well as helping with the development of new approaches to treating this disease.
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PMID:Establishment of syngeneic murine model for oral cancer therapy. 3134 90