Enhancement of Tumor Cell Death by Combining gef Gene Mediated Therapy and New 1,4-Benzoxazepin-2,6-Dichloropurine Derivatives in Breast Cancer Cells

1,5-Benzoxazepines as a unique and potent scaffold for activity drugs: A review

Benzoxazepines constitute a huge number of organic compounds widely described in the literature. Many of them are distinguished by their biological properties. Among them, our attention was drawn to 1,5-benzoxazepine derivatives due to their interesting pharmacological properties. As is reported in the literature, these compounds are not only good building blocks in organic synthesis but also have interesting biological and pharmacological properties. This article is the first review publication to describe the synthesis methods and unique properties of 1,5-benzoxazepines. Literature reports widely describe the biological properties of 1,5-benzoxazepine, like anticancer, antibacterial, or antifungal activities. 1,5-Benzoxazepine derivatives can also interact with G-protein-coupled receptors and could be incorporated into new potential drugs, among others, in treating neuronal disorders like Alzheimer's and Parkinson's disease.

Silver Nanoparticles from Annona muricata Peel and Leaf Extracts as a Potential Potent, Biocompatible and Low Cost Antitumor Tool

Cancer is one of the most prevalent diseases in the world and requires new therapies for its treatment. In this context, the biosynthesis of silver nanoparticles (AgNPs) has been developed to treat different types of tumors. The Annona muricata plant is known for having anticancer activity. Its main compounds present in the leaves, stems and skin, allowing for its use as reducing agents. In this manuscript, AgNPs with leaf extract (AgNPs-LE) and fruit peel extract (AgNPs-PE) of A. muricata were biosynthesized obtaining an average nanoparticle diameter sizes smaller than 50 nm, being 19.63 ± 3.7 nm and 16.56 ± 4.1 nm, and with a surface plasmonic resonance (SPR) at 447 and 448 nm, respectively. The lactone functional group present in the LE and PE extracts was identified by the FTIR technique. The behavior and antiproliferation activity of AgNPs-LE and AgNPs-PE were evaluated in breast, colon and melanoma cancer cell lines. Our results showed that Annona muricata fruit peel, which is a waste product, has an antitumor effect more potent than leaf extract. This difference is maintained with AgNPs where the destruction of cancer cells was, for the first time, achieved using concentrations that do not exceed 3 μg/mL with a better therapeutic index in the different tumor strains. In conclusion, we present a low-cost one-step experimental setup to generate AgNPs-PE whose in-vitro biocompatibility and powerful therapeutic effect make it a very attractive tool worth exploiting.

Large-Scale Production of Lentiviral Vectors: Current Perspectives and Challenges

Lentiviral vectors (LVs) have gained value over recent years as gene carriers in gene therapy. These viral vectors are safer than what was previously being used for gene transfer and are capable of infecting both dividing and nondividing cells with a long-term expression. This characteristic makes LVs ideal for clinical research, as has been demonstrated with the approval of lentivirus-based gene therapies from the Food and Drug Administration and the European Agency for Medicine. A large number of functional lentiviral particles are required for clinical trials, and large-scale production has been challenging. Therefore, efforts are focused on solving the drawbacks associated with the production and purification of LVsunder current good manufacturing practice. In recent years, we have witnessed the development and optimization of new protocols, packaging cell lines, and culture devices that are very close to reaching the target production level. Here, we review the most recent, efficient, and promising methods for the clinical-scale production ofLVs.

Nanoparticles-based drug delivery and gene therapy for breast cancer: Recent advancements and future challenges

Breast cancer (BC) is amongst the most lethal cancer among females and conventional treatment methods like surgery, radiotherapy and chemotherapy are not effective enough as expected and suffer concerns of low bioavailability, low cellular uptake, emerging resistance, and adverse toxicities. Gene therapy using free nucleic acids has potential to deal with key candidate genes of BC, but their effect is retarded due to poor cell uptake and instability in circulation. The rapidly evolving field of nanomedicine aiming targeted drug/gene delivery curtailing BC promises to overcome the limitations of conventional therapies. Nanoparticles can be game changer for BC gene therapy as they can be effective carrier of specific drug/gene by improving the circulation time, enhancing bioavailability, reducing the immune system based recognition chances, and delivering the gene regulator accurately. Herein, we discuss the mechanism of nanoparticles targeted drug delivery, recent advancement of therapeutic strategies of nanoparticles based carriers for small interfering RNA, and microRNA, and gene augmentation therapies in BC. We also discuss the future prospect and challenges of nanoparticle-based therapies for BC.

LdrB Toxin with In Vitro and In Vivo Antitumor Activity as a Potential Tool for Cancer Gene Therapy

Due to the high prevalence of cancer in recent years, it is necessary to develop new and more effective therapies that produce fewer side effects. Development of gene therapy for cancer based on the use of suicide genes that can damage the tumor cell, without requiring a prodrug for its lethal effect, is one of the recent foci of gene therapy strategies. We evaluated the cytotoxic impact of the LdrB toxin from Escherichia coli k12 as a possible tool for cancer gene therapy. For that, colorectal and breast cancer cells were transfected under the control of a TRE3G promoter inducible by doxycycline. Our results showed that ldrB gene expression induced a drastic inhibition of proliferation in vitro, in both 2D and 3D experimental models. Moreover, unlike conventional chemotherapy, the ldrB gene induced a severe loss of proliferation in vivo without any side effects in our animal model. This antitumor outcome was modulated by cell cycle arrest in the G0/G1 phase and apoptotic death. Scanning electronic microscopy demonstrates that the LdrB toxin conserves its pore-forming ability in HCT-116 cells as in E. coli k12. Taken together, our results provide, for the first time, a proof of concept of the antitumor capacity of the ldrB gene in colorectal and breast cancer.

Deciphering the Mechanism of Action Involved in Enhanced Suicide Gene Colon Cancer Cell Killer Effect Mediated by Gef and Apoptin

Despite the great advances in cancer treatment, colorectal cancer has emerged as the second highest cause of death from cancer worldwide. For this type of tumor, the use of suicide gene therapy could represent a novel therapy. We recently demonstrated that co-expression of gef and apoptin dramatically inhibits proliferation of the DLD-1 colon cell line. In the present manuscript, we try to establish the mechanism underlying the enhanced induction of apoptosis by triggering both gef and apoptin expression in colon tumor cells. Scanning microscopy reveals that simultaneous expression of gef and apoptin induces the apparition of many "pores" in the cytoplasmic membrane not detected in control cell lines. The formation of pores induced by the gef gene and accentuated by apoptin results in cell death by necrosis. Moreover, we observed the presence of apoptotic cells. Performing protein expression analysis using western blot, we revealed an activation of mitochondrial apoptosis (increased expression of Pp53, cytochrome c, Bax, and caspase 9) and also the involvement of the extrinsic pathway through caspase 8activation. In conclusion, in this manuscript we demonstrate for the first time that the extrinsic pathway of apoptosis and pore formation is also involved in the cell death caused by the co-expression of the gef and apoptin genes. Our results suggest that co-expression of gef and apoptin genes induces an increase in post-apoptotic necrotic cell death and could be a valuable tool in the design of new antitumor strategies focused on the enhancement of the immune response against cancer cell death.