Antitumor activity of TRAIL recombinant adenovirus in human malignant glioma cells

Combination of Oncolytic Virotherapy with Different Antitumor Approaches against Glioblastoma

Glioblastoma is one of the most malignant and aggressive tumors of the central nervous system. Despite the standard therapy consisting of maximal surgical resection and chemo- and radiotherapy, the median survival of patients with this diagnosis is about 15 months. Oncolytic virus therapy is one of the promising areas for the treatment of malignant neoplasms. In this review, we have focused on emphasizing recent achievements in virotherapy, both as a monotherapy and in combination with other therapeutic schemes to improve survival rate and quality of life among patients with glioblastoma.

Detection of Anticancer and Apoptotic Effect of the Produced IgYs against the Three Extracellular Domain of Human DR5 Protein

BACKGROUND

TNFα cytokine family in the body plays divers' roles in the cellular events such as cell proliferation, differentiation, necrosis, septic shock and apoptosis. In response to TNF therapy, several cell signaling pathways activated in cells which in different manners can lead to apoptosis or necrosis. However induction of apoptosis is depended on one of its important members, TRAIL and its receptors that will be followed by apoptosis activity. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and especially the DR5, is generating considerable interests as a possible anticancer therapeutic agent because of its selective activation in apoptosis of this receptor as a superior affinity to ligands.

METHODS

The study was performed in invitro assay and the anticancer effects of the produced antibodies were assumed by MTT and flowcytometric methods. In the first step for immunization of the hens, three selective small peptides from extracellular domain of DR5 which were chemically synthesized, injected to hens and after the proper immunization of them, IgYs were extracted from the egg yolk. After assumption of specificity of the purified IgYs against the whole DR5 protein, they were performed in MTT assay and flowcytometric colorimeter.

RESULTS

After confirmation of synthesized peptides they were injected to hens with Fround`s complete adjuvant. With completing the immunization procedure the specificity of purified IgYs were confirmed by ELISA. The antibodies were significantly killed the MCF7 breast cancer cells, but had divers affect (proliferative) on normal hepatocyte cells. Additionally, significantly they induced apoptosis on the cancerous cells in contrast to control cells.

CONCLUSION

The results clearly demonstrated that the produced IgYs with reduced cost and time managing could remarkably use as an effective anticancer drug.

Encapsulated stem cells for cancer therapy

Stem cells have inherent tumor‑trophic migratory properties and can serve as vehicles for delivering effective, targeted therapy to isolated tumors and metastatic disease, making them promising anti‑cancer agents. Encapsulation of therapeutically engineered stem cells in hydrogels has been utilized to provide a physical barrier to protect the cells from hostile extrinsic factors and significantly improve the therapeutic efficacy of transplanted stem cells in different models of cancer. This review aims to discuss the potential of different stem cell types for cancer therapy, various engineered stem cell based therapies for cancer, stem cell encapsulation process and provide an in depth overview of current applications of therapeutic stem cell encapsulation in the highly malignant brain tumor, glioblastoma multiforme (GBM), as well as the prospects for their clinical translation.

Efficacy of adenovirally expressed soluble TRAIL in human glioma organotypic slice culture and glioma xenografts

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis in malignant cells, including gliomas, and is currently in anticancer clinical trials. However, the full-length and tagged forms of TRAIL, unlike the untagged ligand (soluble TRAIL (sTRAIL)), exhibits toxicity against normal cells. Here, we report the generation and testing of an adenovirus (AdsTRAIL) that expresses untagged sTRAIL in an intracranial xenograft model and a human glioma organotypic slice culture model. AdsTRAIL efficiently induced apoptosis in glioma cell lines, including those resistant to sTRAIL, but not in normal human astrocytes (NHAs). It inhibited anchorage-independent glioma growth and exerted a bystander effect in transwell assays. Intratumoral injections of AdsTRAIL in a rodent intracranial glioma model resulted in reduced tumor growth and improved survival compared with Ad-enhanced green fluorescent protein (EGFP)- or vehicle-treated controls without toxicity. Human glioma organotypic slices treated with AdsTRAIL demonstrated apoptosis induction and caspase activation.

TRAIL in cancer therapy: present and future challenges

Since its identification in 1995, TNF-related apoptosis-inducing ligand (TRAIL) has sparked growing interest in oncology due to its reported ability to selectively trigger cancer cell death. In contrast to other members of the TNF superfamily, TRAIL administration in vivo is safe. The relative absence of toxic side effects of this naturally occurring cytokine, in addition to its antitumoural properties, has led to its preclinical evaluation. However, despite intensive investigations, little is known in regards to the mechanisms underlying TRAIL selectivity or efficiency. An appropriate understanding of its physiological relevance, and of the mechanisms controlling cancer cells escape from TRAIL-induced cell death, will be required to optimally use the cytokine in clinics. The present review focuses on recent advances in the understanding of TRAIL signal transduction and discusses the existing and future challenges of TRAIL-based cancer therapy development.