Evaluation of Therapeutic Potential of Phenoxodiol, a Novel Isoflavone Analog, in Renal Cancer Cells

Investigating regulated signaling pathways in therapeutic targeting of non-small cell lung carcinoma

Non-small cell lung carcinoma (NSCLC) is the most common malignancy worldwide. The signaling cascades are stimulated via genetic modifications in upstream signaling molecules, which affect apoptotic, proliferative, and differentiation pathways. Dysregulation of these signaling cascades causes cancer-initiating cell proliferation, cancer development, and drug resistance. Numerous efforts in the treatment of NSCLC have been undertaken in the past few decades, enhancing our understanding of the mechanisms of cancer development and moving forward to develop effective therapeutic approaches. Modifications of transcription factors and connected pathways are utilized to develop new treatment options for NSCLC. Developing designed inhibitors targeting specific cellular signaling pathways in tumor progression has been recommended for the therapeutic management of NSCLC. This comprehensive review provided deeper mechanistic insights into the molecular mechanism of action of various signaling molecules and their targeting in the clinical management of NSCLC.

Anticancer properties of arylchromenes and arylchromans: an overview

Cancers are a set of pathologies originated by cells that have the ability to divide and multiply uncontrollably, associated with the capacity to invade and colonize adjacent tissues. Chemotherapy is one of the main approaches of treatment for cancer patients. Despite of the numerous antineoplastic drugs available, cancer cannot be cured; particularly at the late stages deprived of any side effect. Arylchromenes and arylchromans are a group of small molecules, of natural or synthetic origin, of great interest as prototypes for the drug development, especially against cancer. In this chapter, we will present the antineoplastic activity studies of the most promising examples of these arylchromenes and arylchroman derivatives.

The role of isoflavones in augmenting the effects of radiotherapy

Cancer is one of the major health problems and the second cause of death worldwide behind heart disease. The traditional soy diet containing isoflavones, consumed by the Asian population in China and Japan has been identified as a protective factor from hormone-related cancers. Over the years the research focus has shifted from emphasizing the preventive effect of isoflavones from cancer initiation and promotion to their efficacy against established tumors along with chemo- and radiopotentiating effects. Studies performed in mouse models and results of clinical trials emphasize that genistein or a mixture of isoflavones, containing in traditional soy diet, could be utilized to both potentiate the response of cancer cells to radiotherapy and reduce radiation-induced toxicity in normal tissues. Currently ongoing clinical research explores a potential of another significant isoflavone, idronoxil, also known as phenoxodiol, as radiation enhancing agent. In the light of the recent clinical findings, this article reviews the accumulated evidence which support the clinically desirable interactions of soy isoflavones with radiation therapy resulting in improved tumor treatment. This review discusses important aspects of the development of isoflavones as anticancer agents, and mechanisms potentially relevant to their activity in combination with radiation therapy of cancer. It gives a critical overview of studies characterizing isoflavone targets such as topoisomerases, ENOX2/PMET, tyrosine kinases and ER receptor signaling, and cellular effects on the cell cycle, DNA damage, cell death, and immune responses.

Interval Between Cancer Diagnosis and Radiotherapy - An Independent Prognostic Factor of Survival in Patients Irradiated for Bone Metastases from Kidney Cancer

BACKGROUND/AIM

Cancer patients with metastatic disease require personalized treatment regimens. This study was performed to identify prognostic factors for overall survival (OS) following irradiation of bone metastases from kidney cancer.

PATIENTS AND METHODS

Data of 29 patients irradiated for bone metastases from kidney cancer were retrospectively evaluated. Ten factors were analyzed, including age, gender, performance score, interval from diagnosis of kidney cancer until radiotherapy for bone metastases, visceral metastases, other bone metastases, metastatic sites, number of irradiated sites, surgery of irradiated sites and systemic treatment prior to radiotherapy.

RESULTS

Using univariate analyses, a longer interval from diagnosis of kidney cancer radiotherapy was associated with better OS (p=0.012). Using Cox regression analysis, this factor remained significant (risk ratio=3.54, p=0.012).

CONCLUSION

The interval from diagnosis of kidney cancer until radiotherapy is an independent prognostic factor associated with OS following irradiation of bone metastases from kidney cancer. This type of data can help personalize radiation programs.

Phytochemical-Based Nanomedicine for Advanced Cancer Theranostics: Perspectives on Clinical Trials to Clinical Use

In the current chapter, a new strategic compilation of phytochemicals with potent antitumor properties has been addressed, most importantly focusing on cell cycle arrest and apoptotic signaling mechanism. A promising approach in tumor prevention is to eliminate cancer cells preferably via cell cycle arrest and programmed cell death with lesser harm to neighboring normal cells. Cancer cells have a survival advantage to escape apoptosis and relentlessly divide to proliferate, gearing up the cell cycle process. Recently, the use of phytochemical-derived conjugated chemotherapeutic agents has increased dramatically owing to its biocompatibility, low cytotoxicity, low resistance, and dynamic physiochemical properties discriminating normal cells in the treatment of various cancer types. For decades, biomedical investigations have targeted cell cycle and apoptotic cell death mechanism as an effective cancer-killing tool for systemically assessing the potential biological interactions of functional phytocompounds compared to its synthetic counterparts during their complete life cycles from entry, biodistribution, cellular/molecular interactions to excretion. Newly emerging nanotechnology application in anticancer drug formulations has revolutionized cancer therapy. Tissue-specific phyto-nanomedicine plays a vital role in advanced cancer diagnostics using liposome, micelle, and nanoparticles as a precise and effective delivery vehicle. This chapter specifically focuses on the therapeutic phytomolecules approved by the Food and Drug Administration (FDA, USA) along with phyto-chemopreventives currently on clinical trials (Phase-I/II/III/IV). Besides, detailed coverage is given to the FDA-approved nanotechnology-based formulations only in the areas of cancer theranostics via cell cycle arrest and apoptotic pathways including present challenges and future perspectives.

Phenoxodiol sensitizes metastatic colorectal cancer cells to 5-fluorouracil- and oxaliplatin-induced apoptosis through intrinsic pathway

Colorectal cancer (CRC) is one of the most common types of cancer seen in the world. 5-Fluorouracil (5-Fu) plus Oxaliplatin (1-OHP) remains the backbone of CRC chemotherapeutics, but with limited success. Phenoxodiol (Pxd) is an isoflavone analog with antitumor activity against various types of cancers, and sensitizes chemoresistant cancer cells to chemotherapeutics including platinum and taxanes. This study was, therefore, undertaken to examine whether Pxd pre-treatment with conventional chemotherapeutic agent(s) 5-Fu and 1-OHP co-administration be a therapeutic strategy for CRC. Cell viability and cytotoxicity were evaluated using dimethyl-thiazolyl diphenyl tetrazolium bromide (MTT) and lactate dehydrogenase assays. The percentage of apoptotic and necrotic cells were determined by fluorescence microscopy analysis. Besides, active Caspase-3 levels by ELISA and relative mRNA levels of Caspase 3 (CASP3), CASP8 and CASP9 genes were determined by quantitative real-time PCR (qPCR) analysis. The pre-treatment of Pxd followed by 5-Fu and 1-OHP co-administration was more effective at inhibiting cell viability than either chemotherapeutic agents treatment alone. When compared to 5-Fu with 1-OHP alone treatment, Pxd pre-treatment overwhelmingly increased apoptotic Caspase-3 activity levels in CRC cells. Moreover, qPCR analyses showed that CASP3 and CASP9 mRNA levels significantly increased after pre-treatment with Pxd followed by 5-Fu and 1-OHP treatments, compared to 5-Fu with 1-OHP alone. Our results suggested that Pxd enhanced the in vitro antitumor activity of 5-Fu and 1-OHP. Our study also suggested that Pxd may be a potential candidate agent in advanced CRC and inclusion of Pxd to the conventional chemotherapeutic agent(s) could be an effective therapeutic strategy for CRC.

Triggering of eryptosis, the suicidal erythrocyte death, by phenoxodiol

Phenoxodiol is used for the treatment of malignancy. The substance is effective by triggering suicidal tumor cell death or apoptosis. At least in theory, phenoxodiol could similarly stimulate suicidal erythrocyte death or eryptosis. Eryptosis is characterized by cell shrinkage and breakdown of cell membrane asymmetry with phosphatidylserine translocation to the erythrocyte surface. Signaling of eryptosis includes increase of cytosolic Ca²⁺ activity ([Ca²⁺]_i), formation of reactive oxygen species (ROS), and increase of ceramide abundance at the cell surface. The present study explored whether phenoxodiol induces eryptosis and whether it modifies Ca²⁺ entry, ROS, and ceramide. Using flow cytometry, phosphatidylserine exposure at the cell surface was quantified from annexin V binding, cell volume from forward scatter, [Ca²⁺]_i from Fluo3 fluorescence, ROS from DCFDA-dependent fluorescence, and ceramide abundance utilizing specific antibodies. A 48-h exposure of human erythrocytes to phenoxodiol (100 μg/ml [416 μM]) significantly increased the percentage of annexin V binding cells, significantly decreased average forward scatter and Fluo3 fluorescence and significantly increased ceramide abundance, but did not significantly modify DCFDA fluorescence. The effect of phenoxodiol on annexin V binding tended to decrease following removal of extracellular Ca²⁺, an effect, however, not reaching statistical significance. In conclusion, phenoxodiol triggers eryptosis, an effect paralleled by increase of ceramide abundance.

Targeting Cancer with Phytochemicals via Their Fine Tuning of the Cell Survival Signaling Pathways

The role of phytochemicals as potential prodrugs or therapeutic substances against tumors has come in the spotlight in the very recent years, thanks to the huge mass of encouraging and promising results of the in vitro activity of many phenolic compounds from plant raw extracts against many cancer cell lines. Little but important evidence can be retrieved from the clinical and nutritional scientific literature, where flavonoids are investigated as major pro-apoptotic and anti-metastatic compounds. However, the actual role of these compounds in cancer is still far to be fully elucidated. Many of these phytochemicals act in a pleiotropic and poorly specific manner, but, more importantly, they are able to tune the reactive oxygen species (ROS) signaling to activate a survival or a pro-autophagic and pro-apoptosis mechanism, depending on the oxidative stress-responsive endowment of the targeted cell. This review will try to focus on this issue.