Enhancing mda-7/IL-24 therapy in renal carcinoma cells by inhibiting multiple protective signaling pathways using sorafenib and by Ad.5/3 gene delivery.
We have determined whether an adenovirus that comprises the tail and shaft domains of a serotype 5 virus and the knob domain of a serotype 3 virus expressing MDA-7/IL-24, Ad.5/3-mda-7, more effectively infects and kills renal carcinoma cells (RCCs) compared to a serotype 5 virus, Ad.5-mda-7. RCCs are a tumor cell type that generally does not express the receptor for the type 5 adenovirus; the coxsackie and adenovirus receptor (CAR). Ad.5/3-mda-7 infected RCCs to a much greater degree than Ad.5-mda-7. MDA-7/IL-24 protein secreted from Ad.5/3-mda-7-infected RCCs induced MDA-7/IL-24 expression and promoted apoptosis in uninfected "bystander" RCCs. MDA-7/IL-24 killed both infected and bystander RCCs via CD95 activation. Knockdown of intracellular MDA-7/IL-24 in uninfected RCCs blocked the lethal effects of conditioned media. Infection of RCC tumors in one flank, with Ad.5/3-mda-7, suppressed growth of infected tumors and reduced the growth rate of uninfected tumors implanted on the opposite flank. The toxicity of the serotype 5/3 recombinant adenovirus to express MDA-7/IL-24 was enhanced by combined molecular or small molecule inhibition of MEK1/2 and PI3K; inhibition of mTOR, PI3K and MEK1/2; or use of the multi-kinase inhibitor sorafenib. In RCCs, combined inhibition of cytoprotective cell signaling pathways enhanced the MDA-7/IL-24-induction of CD95 activation, with greater mitochondrial dysfunction due to loss of MCL-1 and BCL-XL expression, and tumor cell death. Treatment of RCC tumors in vivo with sorafenib also enhanced Ad.5/3-mda-7 toxicity and prolonged animal survival. Future combinations of these approaches hold promise for developing a more effective therapy for kidney cancer.
Departments of Biochemistry and Molecular Biology, Virginia Commonwealth University, School of Medicine, 401 College St., Richmond, VA 23298, USA.
Patrick J
PJ
Eulitt
Margaret A
MA
Park
Hamed
H
Hossein
Nichola
N
Cruikshanks
Chen
C
Yang
Igor P
IP
Dmitriev
Adly
A
Yacoub
David T
DT
Curiel
Paul B
PB
Fisher
Paul
P
Dent
D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D017209:Apoptosis; D001557:Benzenesulfonates / Q000276:immunology / Q000627:therapeutic use*; D015153:Blotting, Western; D002292:Carcinoma, Renal Cell / Q000628:therapy*; D045744:Cell Line, Tumor; D017077:Culture Media, Conditioned; D055785:Gene Knockdown Techniques; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D006801:Humans; D007378:Interleukins / Q000235:genetics*; D007680:Kidney Neoplasms / Q000628:therapy*; D051379:Mice; D008928:Mitochondria / Q000378:metabolism; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D009536:Niacinamide / Q000031:analogs & derivatives; D010671:Phenylurea Compounds; D000081082:Phosphoinositide-3 Kinase Inhibitors; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D011725:Pyridines / Q000276:immunology / Q000627:therapeutic use*; D015398:Signal Transduction; D000077157:Sorafenib; D058570:TOR Serine-Threonine Kinases / Q000037:antagonists & inhibitors; D051020:bcl-X Protein / Q000235:genetics; D019014:fas Receptor / Q000276:immunology / Q000378:metabolism; D000099180:Interleukin-24
D001557:Benzenesulfonates; D017077:Culture Media, Conditioned; D007378:Interleukins; D020929:Mitogen-Activated Protein Kinase Kinases; D009536:Niacinamide; D010671:Phenylurea Compounds; D000081082:Phosphoinositide-3 Kinase Inhibitors; D019253:Proto-Oncogene Proteins c-bcl-2; D011725:Pyridines; D000077157:Sorafenib; D058570:TOR Serine-Threonine Kinases; D051020:bcl-X Protein; D019014:fas Receptor; D000099180:Interleukin-24