mda-7/IL-24: multifunctional cancer-specific apoptosis-inducing cytokine.
ABSTRACT "Differentiation therapy" provides a unique and potentially effective, less toxic treatment paradigm for cancer. Moreover, combining "differentiation therapy" with molecular approaches presents an unparalleled opportunity to identify and clone genes mediating cancer growth control, differentiation, senescence, and programmed cell death (apoptosis). Subtraction hybridization applied to human melanoma cells induced to terminally differentiate by treatment with fibroblast interferon (IFN-beta) plus mezerein (MEZ) permitted cloning of melanoma differentiation associated (mda) genes. Founded on its novel properties, one particular mda gene, mda-7, now classified as a member of the interleukin (IL)-10 gene family (IL-24) because of conserved structure, chromosomal location, and cytokine-like properties has become the focus of attention of multiple laboratories. When administered by transfection or adenovirus-transduction into a spectrum of tumor cell types, melanoma differentiation associated gene-7/interleukin-24 (mda-7/IL-24) induces apoptosis, whereas no toxicity is apparent in normal cells. mda-7/IL-24 displays potent "bystander antitumor" activity and also has the capacity to enhance radiation lethality, to induce immune-regulatory activities, and to inhibit tumor angiogenesis. Based on these remarkable attributes and effective antitumor therapy in animal models, this cytokine has taken the important step of entering the clinic. In a Phase I clinical trial, intratumoral injections of adenovirus-administered mda-7/IL-24 (Ad.mda-7) was safe, elicited tumor-regulatory and immune-activating processes, and provided clinically significant activity. This review highlights our current understanding of the diverse activities and properties of this novel cytokine, with potential to become a prominent gene therapy for cancer.
Cancer Research 10/1993; 53(17):4109-15. · 7.86 Impact Factor
Article: A pooled analysis of eastern cooperative oncology group and intergroup trials of adjuvant high-dose interferon for melanoma.[show abstract] [hide abstract]
ABSTRACT: Nearly 2000 patients with stage IIB and III melanoma have participated in four multicenter, randomized trials, conducted by the Eastern Cooperative Oncology Group and the Intergroup, investigating adjuvant high-dose IFN-alpha 2b therapy. The objectives of this study were to update the analyses of each individual trial and to analyze prognostic factors and treatment effects based on pooled data. Survival and disease status were updated to April 2001. Analysis of prognostic factors using optimized statistical models was based on data from patients in E1684, E1690, E1694, and E2696. Analysis of treatment effects versus observation (Obs) was based on data from 713 patients randomized to high-dose IFN-alpha 2b (HDI) or Obs in Trials E1684 and E1690. Updated analysis of E1684, E1690, and E1694 confirmed their original conclusions, now at median follow-up intervals of 2.1-12.6 years. Based on two-sided univariate log-rank analysis of pooled data from E1684 and E1690 (median follow-up, 7.2 years), relapse-free survival (RFS)-but not overall survival (OS)-was significantly prolonged (two-sided log-rank P value = 0.006) for patients treated with HDI versus Obs. Among all patients, prognostic factors that significantly negatively impacted RFS and OS included ulceration, recurrent disease at entry, enrollment in E1684, and age > 49 years. Multivariate statistical models adjusting for these factors confirmed the statistically significant RFS benefit of HDI versus Obs but did not demonstrate a significant OS benefit in the pooled populations. In patients with high-risk resected melanoma, HDI is effective adjuvant therapy with strong evidence for improved RFS and evidence for moderate improvement in OS based on two prospective randomized studies but not the pooled analysis. Analyses of predictors of relapse and response are now needed to improve the therapeutic value of this modality.Clinical Cancer Research 03/2004; 10(5):1670-7. · 7.74 Impact Factor
Article: A combinatorial approach for selectively inducing programmed cell death in human pancreatic cancer cells.[show abstract] [hide abstract]
ABSTRACT: Pancreatic cancer is an extremely aggressive neoplasm whose incidence equals its death rate. Despite intensive analysis, the genetic changes that mediate pancreatic cancer development and effective therapies for diminishing the morbidity associated with this disease remain unresolved. Through subtraction hybridization, we have identified a gene associated with induction of irreversible growth arrest, cancer reversion, and terminal differentiation in human melanoma cells, melanoma differentiation associated gene-7 (mda-7). Ectopic expression of mda-7 when using a recombinant adenovirus, Ad.mda-7, results in growth suppression and apoptosis in a broad spectrum of human cancers with diverse genetic defects, without exerting deleterious effects in normal human epithelial or fibroblast cells. Despite the apparently ubiquitous antitumor effects of mda-7, pancreatic carcinoma cells are remarkably refractory to Ad.mda-7 induced growth suppression and apoptosis. In contrast, the combination of Ad.mda-7 with antisense phosphorothioate oligonucleotides, which target the K-ras oncogene (a gene that is mutated in 85 to 95% of pancreatic carcinomas), induces a dramatic suppression in growth and a decrease in cell viability by induction of apoptosis. In mutant K-ras pancreatic carcinoma cells, programmed cell death correlates with expression and an increase, respectively, in MDA-7 and BAX proteins and increases in the ratio of BAX to BCL-2 proteins. Moreover, transfection of mutant K-ras pancreatic carcinoma cells with an antisense K-ras expression vector and infection with Ad.mda-7 inhibits colony formation in vitro and tumorigenesis in vivo in nude mice. These intriguing observations demonstrate that a combinatorial approach, consisting of a cancer-specific apoptosis-inducing gene and an oncogene inactivation strategy, may provide the foundation for developing an effective therapy for pancreatic cancer.Proceedings of the National Academy of Sciences 09/2001; 98(18):10332-7. · 9.68 Impact Factor