Gene Therapy with p14/tBID Induces Selective and Synergistic Apoptosis in Mutant Ras and Mutant p53 Cancer Cells In Vitro and In Vivo

• Published in: Biomedicines Vol. 11; no. 2; p. 258
• Main Authors: Fine, Robert L., Mao, Yuehua, Garcia-Carracedo, Dario, Su, Gloria H., Qiu, Wanglong, Hochfeld, Uri, Nichols, Gwen, Li, Yong-Liang, Dinnen, Richard D., Raffo, Anthony, Brandt-Rauf, Paul W.
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 18.01.2023; MDPI
• Subjects: Activator protein 1; Adenoviruses; Apoptosis; Bone marrow; Cancer; Care and treatment; Cell activation; Cell cycle; Cell differentiation; Chemoresistance; Chemotherapy; Cloning; E2F protein; Gene therapy; Genetic aspects; Health aspects; Lung cancer; MDR1 protein; Methods; Mutants; Mutation; p14; p14ARF promoter; p53; p53 Protein; Pancreatic cancer; Physiological aspects; Plasmids; Ras genes; Stem cells; Tata box; tBID; Toxicity; Transcription factors; Transcription initiation; Tumor proteins; Tumors; Vectors (Biology); United States; St Louis Missouri; Palo Alto California; United States > US; p14; Ras; p14ARF promoter; apoptosis; gene therapy; tBID; p53
• ISSN: 2227-9059; 2227-9059
• DOI: 10.3390/biomedicines11020258

Any gene therapy for cancer will be predicated upon its selectivity against cancer cells and non-toxicity to normal cells. Therefore, safeguards are needed to prevent its activation in normal cells. We designed a minimal p14ARF promoter with upstream Ap1 and E2F enhancer elements and a downstream MDR1 inhibitory element, TATA box, and a transcription initiation site (hereafter p14ARFmin). The modified p14ARFmin promoter was linked to bicistronic P14 and truncated BID (tBID) genes, which led to synergistic apoptosis via the intrinsic and extrinsic pathways of apoptosis when expressed. The promoter was designed to be preferentially activated by mutant Ras and completely inhibited by wild-type p53 so that only cells with both mutant Ras and mutant p53 would activate the construct. In comparison to most p53 gene therapies, this construct has selective advantages: (1) p53-based gene therapies with a constitutive CMV promoter cannot differentiate between normal cells and cancer cells, and can be toxic to normal cells; (2) our construct does not induce p21WAF/CIPI in contrast to other p53-based gene therapies, which can induce cell cycle arrest leading to increased chemotherapy resistance; (3) the modified construct (p14ARFmin-p14-tBID) demonstrates bidirectional control of its promoter, which is completely repressed by wild-type p53 and activated only in cells with both RAS and P53 mutations; and (4) a novel combination of genes (p14 and tBID) can synergistically induce potent intrinsic and extrinsic apoptosis in cancer cells.