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HNSCC Cell Lines (hnscc + cell_line)
Selected AbstractsHyperphosphorylation of replication protein A in cisplatin-resistant and -sensitive head and neck squamous cell carcinoma cell linesHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 5 2010Karoline C. Manthey MS Abstract Background Resistance to chemotherapy is a major limitation in the treatment of head and neck squamous cell carcinomas (HNSCCs), accounting for high mortality rates in patients. Here, we investigated the role of replication protein A (RPA) in cisplatin and etoposide resistance. Methods We used 6 parental HNSCC cell lines. We also generated 1 cisplatin-resistant progeny subline from a parental cisplatin-sensitive cell line, to examine cisplatin resistance and sensitivity with respect to RPA2 hyperphosphorylation and cell-cycle response. Results Cisplatin-resistant HNSCC cell levels of hyperphosphorylated RPA2 in response to cisplatin were 80% to 90% greater compared with cisplatin-sensitive cell lines. RPA2 hyperphosphorylation could be induced in the cisplatin-resistant HNSCC subline. The absence of RPA2 hyperphosphorylation correlated with a defect in cell-cycle progression and cell survival. Conclusion Loss of RPA2 hyperphosphorylation occurs in HNSCC cells and may be a marker of cellular sensitivities to cisplatin and etoposide in HNSCC. © 2009 Wiley Periodicals, Inc. Head Neck, 2010 [source] Head and neck squamous cell carcinoma cell lines: Established models and rationale for selectionHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 2 2007Charles J. Lin BA Abstract Background. Head and neck squamous cell carcinoma (HNSCC) cell lines are important preclinical models in the search for novel and targeted therapies to treat head and neck cancer. Unlike many other cancer types, a wide variety of primary and metastatic HNSCC cell lines are available. An easily accessible guide that organizes important characteristics of HNSCC cell lines would be valuable for the selection of appropriate HNSCC cell lines for in vitro or in vivo studies. Methods. A literature search was performed. Results. Cell growth and culture parameters from HNSCC cell lines were catalogued into tables or lists of selected characteristics. Methods for establishing cancer cell lines and basic cell culture maintenance techniques were reviewed. Conclusions. A compendium of HNSCC cell line characteristics is useful for organizing the accumulating information regarding cell line characteristics to assist investigators with the development of appropriate preclinical models. © 2006 Wiley Periodicals, Inc. Head Neck, 2006 [source] The effect of nitric oxide on cyclooxygenase-2 (COX-2) overexpression in head and neck cancer cell linesINTERNATIONAL JOURNAL OF CANCER, Issue 5 2003Seok-Woo Park Abstract The overexpression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) has been previously reported in head and neck squamous cell carcinoma (HNSCC), as well as in many cancers. We hypothesized that endogenous nitric oxide (NO) might increase the expression of COX-2 in cancer cells. Therefore, we investigated the cross-talk between NO and the prostaglandin (PG) pathways in HNSCC cell lines. We found that COX-2 and iNOS expressions were elevated simultaneously. On adding the NO donor, SNAP, the PGE2 level was increased 2,20 times due to increased COX-2 expression. This increase of COX-2 expression by SNAP or PMA (potent inducer of both iNOS and COX-2) was blocked to various degrees by NO scavengers and NOS inhibitors (L-NAME and 1400W). Also, the expression of COX-2 in resting cells was inhibited by NOS inhibitors. Moreover, COX-2 expression, induced by SNAP, was inhibited by ODQ, a soluble guanylate cyclase (sGC) inhibitor. The effect of dibutyryl-cGMP on COX-2 expression was similar to that of SNAP. These results imply that endogenous or exogenous NO activates sGC and that the resulting increase of cGMP induces a signaling that upregulates the expression of COX-2 in HNSCC cell lines. We also observed that NO increased COX-2 expression in different cancer cell lines, including cervic and gastric cancer cell lines. These findings further support the notion that NO can be associated with carcinogenesis through the upregulation of COX-2, and that NOS inhibitor may be also useful for cancer prevention. © 2003 Wiley-Liss, Inc. [source] EGFR Regulates the Side Population in Head and Neck Squamous Cell CarcinomaTHE LARYNGOSCOPE, Issue 3 2006Jocelyn S. Chen BS Abstract Objective: To identify the presence of side population (SP) cells in established head and neck squamous carcinoma cell (HNSCC) lines and to determine the role of EGFR in the regulation of the side population of these cells. Methods: SP cells were identified using flow cytometry analysis by the ability of these cells to extrude the Hoechst 33342 dye via the drug transporter BCRP1/ABCG2. Effect of EGFR on the side population was determined also by difference in Hoechst extrusion and by immunofluorescence. Immunohistochemical staining was performed to show the presence of the BCRP1/ABCG2 transporter and the phosphorylated form of EGFR in HNSCC tissue. Results: SP cells are present in HNSCC cell lines. With the Hoechst 33342 extrusion assay, SP cells were found to comprise an average of 0.69% of the UMSCC10B cells and 0.91% of HN12 cells. Addition of the EGF ligand increased the SP population while inactivation of the EGFR kinase by Iressa significantly decreased SP. Conclusion: In established head and neck squamous cell carcinoma cell lines, SP cells were found using methods that determine expression and function of the drug transporter BCRP1/ABCG2. Activation of EGFR, a gene implicated in tumorigenesis in HNSCC leads to increased SP, and conversely, inhibition of EGFR leads to decrease in SP. This finding could help explain the role of EGFR in regulating cancer stem cells and thus tumorigenesis in HNSCC. [source] The effects of exogenous p53 overexpression on HPV-immortalized and carcinogen transformed oral keratinocytesCANCER, Issue 1 2002George H. Yoo M.D. Abstract BACKGROUND Overexpression of p53 in head and neck carcinoma cells has demonstrated tumor growth suppression using in vitro and in vivo models. The effects of exogenous overexpression of wild-type p53 on human papilloma virus (HPV),immortalized and carcinogen transformed oral keratinocytes were determined. METHODS The p53 gene was overexpressed in IHGK (immortalized human gingival keratinocyte), IHGKN [4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, (NNK)]-carcinogen transformed keratinocytes, and two head and neck squamous carcinoma (HNSCC) cell lines, HN30 and HN12. The transfection efficiency, growth suppression, and inhibition of the cell cycle along with the induction of apoptosis were measured. RESULTS Transfections with adenoviruses were more efficient for IHGK cells than for IHGKN, HN12, and HN30 cells. Inhibition of proliferation in all cell lines was proportional to the viral particle to cell (VPC) ratios. IHGK cells were more sensitive to p53 than IHGKN cells. HN12 cells were more suppressed than HN30 cells. HN12 were the most suppressed at 72 hours whereas HN30 cells were most suppressed at 24 hours. Expression of exogenous p53-induced G1 cell cycle arrest and p21 expression as VPC ratios increased in IHGK and IHGKN cell lines. Apoptosis also was induced in these cells by p53 as VPC increased. IHGK cells were more sensitive to p53-induced growth inhibition, cell cycle regulation, p21 expression and apoptosis than IHGKN cells. HN12 (mutated p53) cells were more sensitive to p53 overexpression than HN30 (wild-type p53) cells. Gene transfer and expression of exogenous p53 by using Ad-p53 demonstrates suppressive effects on HPV immortalized and carcinogen transformed oral keratinocytes. CONCLUSIONS Cell cycle regulation by gene transfer is feasible in immortalized oral keratinocytes. Carcinogen transformed cells are less susceptible to the effects of p53 overexpression. Expression of exogenous p53 through p53 gene transfer can suppress HPV immortalization and carcinogen transformation in oral keratinocytes. The sensitivity of HNSCC cell lines to p53-induced cell cycle regulation and apoptosis is variable and dependent on the cell line and duration of exposure. In vitro results using p53 gene transfer must be validated in clinical studies with patients at risk for HNSCC. Cancer 2002;94:159,66. © 2002 American Cancer Society. [source] | ||||||||||