Reversing translational suppression and induction of toxicity in pancreatic cancer cells using a chemoprevention gene therapy approach

Stratification of lung adenocarcinoma patients for d-limonene intervention based on the expression signature genes

Globally, lung cancer ranks as the most lethal malignant neoplasm. d-Limonene, a plant extract enriched with essential oils, has been reported to exert anti-cancer effects both in vitro and in vivo; however, its clinical effect on humans remains elusive. Therefore, the present study aimed to investigate the gene expression signature that would potentially stratify lung adenocarcinoma (LUAD) patients who may benefit from d-limonene intervention, thus facilitating the development of newer treatment strategies for LUAD. In total, 1877 significant differentially expressed genes (DEGs) were identified. These genes were mainly associated with the metabolism of terpenoids and polyketides, lipid metabolism, endocrine system, carbohydrate metabolism, and cell growth and death pathways. Three genes, including antioncogenes FZD3 and MTURN, and oncogene PRC1, which were regulated by d-limonene were identified based on survival analysis of TCGA-LUAD data and were validated by both in vitro and in vivo experiments. High-risk patients screened by the model exhibited a significantly poor prognosis. In conclusion, three gene expression signatures (FZD3, MTURN, and PRC1) were validated by both in vitro and in vivo experiments and identified to help stratify candidate lung adenocarcinoma patients who may benefit from d-limonene intervention. Although further studies are warranted, this study highlighted a potential strategy to improve the treatment outcomes of LUAD patients.

Clinical Significance of the Interleukin 24 mRNA Level in Head and Neck Squamous Cell Carcinoma and Its Subgroups: An In Silico Investigation

IL24 mRNA is known to have an apoptotic effect on cancer cells but not on noncancer cells. However, the expression level of the IL24 mRNA in head and neck squamous cell carcinoma (HNSCC) and its subgroups is rarely studied. In this study, the clinical implication of IL24 mRNA was evaluated in the common subgroups of HNSCC, including oral squamous cell carcinoma (OSCC), nasopharyngeal carcinoma (NPC), and laryngeal squamous cell carcinoma (LSCC) for analysis. Substantial IL24 mRNA expression data were calculated from several databases, such as the Gene Expression Omnibus (GEO), ArrayExpress, Sequence Read Archive (SRA), ONCOMINE, and The Cancer Genome Atlas (TCGA) databases. We ultimately collected a total of 41 microarrays and RNA-seq including 1,564 HNSCC and 603 noncancer tissue samples. IL24 mRNA was highly expressed in OSCC, LSCC, and NPC as shown by the separated standard mean difference (SMD), as well as HNSCC as a whole part (SMD = 1.47, 95% confdence interval (CI) = 1.24−1.70, P < 0.0001). In all subgroups, the IL24 mRNA upregulation had the ability to distinguish cancer from noncancer tissue with area under the curves (AUCs) of the summary receiver operating characteristic (sROC) higher than 0.85. In conclusion, IL24 mRNA may be used as a potential marker for cancer screening, and its clinical diagnostic value needs to be further studied. It also provides a new idea for the treatment of the IL24 gene in HNSCC and its subgroups in the future.

Role of MDA-7/IL-24 a Multifunction Protein in Human Diseases

Subtraction hybridization identified genes displaying differential expression as metastatic human melanoma cells terminally differentiated and lost tumorigenic properties by treatment with recombinant fibroblast interferon and mezerein. This approach permitted cloning of multiple genes displaying enhanced expression when melanoma cells terminally differentiated, called melanoma differentiation associated (mda) genes. One mda gene, mda-7, has risen to the top of the list based on its relevance to cancer and now inflammation and other pathological states, which based on presence of a secretory sequence, chromosomal location, and an IL-10 signature motif has been named interleukin-24 (MDA-7/IL-24). Discovered in the early 1990s, MDA-7/IL-24 has proven to be a potent, near ubiquitous cancer suppressor gene capable of inducing cancer cell death through apoptosis and toxic autophagy in cancer cells in vitro and in preclinical animal models in vivo. In addition, MDA-7/IL-24 embodied profound anticancer activity in a Phase I/II clinical trial following direct injection with an adenovirus (Ad.mda-7; INGN-241) in tumors in patients with advanced cancers. In multiple independent studies, MDA-7/IL-24 has been implicated in many pathological states involving inflammation and may play a role in inflammatory bowel disease, psoriasis, cardiovascular disease, rheumatoid arthritis, tuberculosis, and viral infection. This review provides an up-to-date review on the multifunctional gene mda-7/IL-24, which may hold potential for the therapy of not only cancer, but also other pathological states.

Suppression of Her2/Neu mammary tumor development in mda-7/IL-24 transgenic mice

Melanoma differentiation associated gene-7/interleukin-24 (mda-7/IL-24) encodes a tumor suppressor gene implicated in the growth of various tumor types including breast cancer. We previously demonstrated that recombinant adenovirus-mediated mda-7/IL-24 expression in the mammary glands of carcinogen-treated (methylnitrosourea, MNU) rats suppressed mammary tumor development. Since most MNU-induced tumors in rats contain activating mutations in Ha-ras, which arenot frequently detected in humans, we presently examined the effect of MDA-7/IL-24 on Her2/Neu-induced mammary tumors, in which the RAS pathway is induced. We generated tet-inducible MDA-7/IL-24 transgenic mice and crossed them with Her2/Neu transgenic mice. Triple compound transgenic mice treated with doxycycline exhibited a strong inhibition of tumor development, demonstrating tumor suppressor activity by MDA-7/IL-24 in immune-competent mice. MDA-7/IL-24 induction also inhibited growth of tumors generated following injection of Her2/Neu tumor cells isolated from triple compound transgenic mice that had not been treated with doxycycline, into the mammary fat pads of isogenic FVB mice. Despite initial growth suppression, tumors in triple compound transgenic mice lost mda-7/IL-24 expression and grew, albeit after longer latency, indicating that continuous presence of this cytokine within tumor microenvironment is crucial to sustain tumor inhibitory activity. Mechanistically, MDA-7/IL-24 exerted its tumor suppression effect on HER2⁺ breast cancer cells, at least in part, through PERP, a member of PMP-22 family with growth arrest and apoptosis-inducing capacity. Overall, our results establish mda-7/IL-24 as a suppressor of mammary tumor development and provide a rationale for using this cytokine in the prevention/treatment of human breast cancer.

mda-7/IL-24 Induces Cell Death in Neuroblastoma through a Novel Mechanism Involving AIF and ATM

Advanced stages of neuroblastoma, the most common extracranial malignant solid tumor of the central nervous system in infants and children, are refractive to therapy. Ectopic expression of melanoma differentiation-associated gene-7/interleukin-24 (mda-7/IL-24) promotes broad-spectrum antitumor activity in vitro, in vivo in preclinical animal models, and in a phase I clinical trial in patients with advanced cancers without harming normal cells. mda-7/IL-24 exerts cancer-specific toxicity (apoptosis or toxic autophagy) by promoting endoplasmic reticulum stress and modulating multiple signal transduction pathways regulating cancer cell growth, invasion, metastasis, survival, and angiogenesis. To enhance cancer-selective expression and targeted anticancer activity of mda-7/IL-24, we created a tropism-modified cancer terminator virus (Ad.5/3-CTV), which selectively replicates in cancer cells producing robust expression of mda-7/IL-24 We now show that Ad.5/3-CTV induces profound neuroblastoma antiproliferative activity and apoptosis in a caspase-3/9-independent manner, both in vitro and in vivo in a tumor xenograft model. Ad.5/3-CTV promotes these effects through a unique pathway involving apoptosis-inducing factor (AIF) translocation into the nucleus. Inhibiting AIF rescued neuroblastoma cells from Ad.5/3-CTV-induced cell death, whereas pan-caspase inhibition failed to promote survival. Ad.5/3-CTV infection of neuroblastoma cells increased ATM phosphorylation instigating nuclear translocation and increased γ-H2AX, triggering nuclear translocation and intensified expression of AIF. These results were validated further using two ATM small-molecule inhibitors that attenuated PARP cleavage by inhibiting γ-H2AX, which in turn inhibited AIF changes in Ad.5/3-CTV-infected neuroblastoma cells. Taken together, we elucidate a novel pathway for mda-7/IL-24-induced caspase-independent apoptosis in neuroblastoma cells mediated through modulation of AIF, ATM, and γ-H2AX. Cancer Res; 76(12); 3572-82. ©2016 AACR.