Efficacy of an improved cancer stroma-targeted oncolytic adenovirus on human derived gynecologic tumor samples

ALEJANDRO NICOLA CANDIA; ANA LAURA ALFANO ; CRISTIAN M. MALNERO ; ISMAEL R. BERMÚDEZ ; NICASIO CUNEO; MARIELA A. GANGEMI ; ALEJANDRO SODERINI ; OSVALDO L PODHAJCER; M VERONICA LOPEZ

New Orleans

Congreso; 18th Annual Meeting of the American Society of Gene & Cell Therapy.; 2015

American Society of Gene & Cell Therapy.

Efficacy of animproved cancer stroma-targeted oncolytic adenovirus on human derivedgynecologic tumor samples Gynecologic cancers originatedin the female reproductive organs, including the cervix, ovaries, uterus,fallopian tubes, vagina and vulva. In2013, it was estimated that 91,730 women would be diagnosed with a gynecologiccancer. Cervical cancer accounted for approximately 13%, ovariancancer 24% and uterine cancer 54% of cases of cancer (AmericanCancer Society, Inc). We have recentlydeveloped a stroma-targeted CRAd also responsive to the tumor microenvironment,AdF512v4, that contain a chimeric promoter that combines a 0.5 Kb of the SPARCpromoter, a Hypoxia-Response Element (HRE) and a NFkB-response element (NFkB).The chimeric promoter drives the expression of delta-RB E1A and the CRAd waspseudotyped with a chimeric fiber 5/3. We also constructed the non-replicativeversion of AdF512v4 (AdF512v4-luc). We have previously demonstrated theactivity of the new promoter in ovarian cancer cell lines. First, we assessed thepromoter activity following transduction of cervix cancer cell lines (HeLa,CaSki and SiHa) with the non-replicative adenovirus. We observed 10-35 foldinduction of luciferase activity under hypoxic condition (0.1% O2) or/and TNFa treatment (5 ng/ml). Next, we measured the efficacy of the CRAd in the 3 cervical cancer cell lines undernormal oxygen levels (21% O2), hypoxic condition or TNFa treatment. Byusing the MTS assay we observed that the larger lytic capacity was obtained inthe presence of TNFa treatment. In order to establish the potential clinical utilityof AdF512v4 we assayed its replication capacity in a most rigorous preclinical settingby using slices obtained from fresh tissue explants of human tumors. AdF512v4replicated in three out of six human cervix cancers, one tumor from uterus andthree of four human ovarian carcinomas with no lytic effect on the pairednormal tissues. It is of note that Ad-wt 5/3 could replicate in both malignantand normal ovarian samples. In conclusion, AdF512v4 demonstrated a strongkilling effect on cervix and ovarian cancer cells in vitro, as well as a replication capacity in fresh human ovary,uterus and cervix cancer explants. AdF512v4 appears safe since no replicationwas observed in normal human ovary raising its potential use in the clinics.