Adenovirus-Mediated FKHRL1/TM Sensitizes Melanoma Cells to Apoptosis Induced by Temozolomide

Abstract

Melanoma exhibits variable resistance to the alkylating agent temozolomide (TMZ). We evaluated the potential of adenovirus expressing forkhead human transcription factor like 1 triple mutant (Ad-FKHRL1/TM) to sensitize melanoma cells to TMZ. Four melanoma cell lines were treated with Ad-FKHRL1/TM and TMZ, alone or in combination. Apoptosis was assessed by activation and inhibition of caspase pathway, nuclei fragmentation, and annexin V staining. The potential therapeutic efficacy of Ad-FKHRL1/TM with TMZ was also assessed in a mouse melanoma xenograft model. Combination therapy of Ad-FKHRL1/TM and TMZ resulted in greater cell killing (<20% cell viability) compared with single therapy and controls (p<0.05). Combination indices of Ad-FKHRL1/TM and TMZ therapy indicated significant (p<0.05) synergistic killing effect. Greater apoptosis induction was found in cells treated with Ad-FKHRL1/TM and TMZ than with Ad-FKHRL1/TM or TMZ-treated cells alone. Treatment with TMZ enhanced adenovirus transgene expression in a cell type-dependent manner. In an in vivo model, combination therapy of Ad-FKHRL1/TM with TMZ results in greater tumor growth reduction in comparison with single treatments. We suggest that Ad-FKHRL1/TM is a promising vector to sensitize melanoma cells to TMZ, and that a combination of both approaches would be effective in the clinical setting.

Combined therapy of oncolytic adenovirus and temozolomide enhances lung cancer virotherapy in vitro and in vivo

“…A549 and H1299 cells were grown in DMEM medium; H441was cultured in RPMI1640 medium; Calu-1 in McCoy's 5a medium; HEK-293 and WI-38 were grown in alpha-MEM medium. All media were supplemented as previously described (Egger et al, 2014). All cell culture reagents were obtained from Corning Cellgro.…”

“…A replication-deficient adenoviral vector AdLacZ expressing β-galactosidase under regulation of cytomegalovirus promoter was used as a control as previously described (Egger et al, 2014). The adenovirus serotype 5 wild type (Adwt) and a CRAd (Adhz60 E1B -deleted) were used as previously reported by us (Rao et al, 2004).…”

“…Cytopathic effect (CPE) was evaluated with crystal violet staining as described previously by our group (Cheng et al, 2015). Cell viability was assessed 72 h after experimental therapy by measuring the conversion the tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) to formazan as described by our group (Egger et al, 2014). For control infection, we used cell line-specific media alone without virus or DMSO instead of TMZ.…”

Temozolomide Enhances Triple-Negative Breast Cancer Virotherapy In Vitro

“…MDA-MB-231 and HEK-293 cells were grown in Dulbecco’s Modified Eagle’s Medium (DMEM) (Cat# 10-013-CV). All media were supplemented as previously described [ 38 ]. All cell culture reagents were obtained from Corning Cellgro (Manassas, VA, USA).…”

Design and Success of a 21st Century Cancer Education Program at the University of Louisville

“…In the first 4 years of the program, cancer education program graduates presented their research at over 35 national and international scientific meetings, including but not limited to the International Endocrine Society, Society of Toxicology, Keystone Symposia on “Cancer Pathophysiology: Integrating the Host and Tumor Environments”, American Association for Cancer Research, International Workshops on Arylamine N-acetyltransferases, Academic Surgical Congress, Keystone Cancer Conference, Biomedical Engineering Society, National Student American Institute of Chemical Engineers, and Society for the Advancement of Chicanos and Native Americans in Science. In addition, several of our trainees published their research findings in scholarly journals [1, 2, 4, 6, 7, 9, 10, 12–19]. …”