Evaluation of resveratrol radiomodifying potential for radiotherapy treatment

The Potential Application of Resveratrol and Its Derivatives in Central Nervous System Tumors

Resveratrol, a naturally occurring polyphenolic compound found in various plants, has been extensively studied for its broad spectrum of beneficial biological effects. These encompass its potent antioxidant properties, anti-inflammatory activities, anti-aging capabilities, cardioprotective functions, and neuroprotective potential. The diverse biological actions of resveratrol extend beyond these well-established properties. It also exerts a significant impact on metabolic processes and bioavailability, and critically, it demonstrates the ability to effectively traverse the blood-brain barrier. This capacity to penetrate the central nervous system renders resveratrol a promising therapeutic agent for the management of central nervous system malignancies, as it has been shown to inhibit tumor cell proliferation, induce apoptosis, and modulate key signaling cascades, such as PI3K/Akt, JAK/STAT, and NF-kB. The multifaceted nature of resveratrol's biological effects, including its influence on diverse physiological processes, underscores its potential as a valuable therapeutic option for the treatment of central nervous system tumors.

Polyphenols as Potential Protectors against Radiation-Induced Adverse Effects in Patients with Thoracic Cancer

Radiotherapy is one of the standard treatment approaches used against thoracic cancers, occasionally combined with chemotherapy, immunotherapy and molecular targeted therapy. However, these cancers are often not highly sensitive to standard of care treatments, making the use of high dose radiotherapy necessary, which is linked with high rates of radiation-induced adverse effects in healthy tissues of the thorax. These tissues remain therefore dose-limiting factors in radiation oncology despite recent technological advances in treatment planning and delivery of irradiation. Polyphenols are metabolites found in plants that have been suggested to improve the therapeutic window by sensitizing the tumor to radiotherapy, while simultaneously protecting normal cells from therapy-induced damage by preventing DNA damage, as well as having anti-oxidant, anti-inflammatory or immunomodulatory properties. This review focuses on the radioprotective effect of polyphenols and the molecular mechanisms underlying these effects in the normal tissue, especially in the lung, heart and esophagus.

Cellular bases of hypofractionated radiotherapy protocols for lung cancer

The extreme demand on health systems due to the COVID-19 pandemic has led to reconsider hypofractionation. Although the best clinical efficacy of these schemes is being demonstrated, the biological bases have not been established. Thus, after validating basic clinical parameters, through complementary in vitro models, we characterized the cellular and molecular mechanisms of hypofractionation protocols. Cell cultures of human lung cancer cell line A549 were irradiated with 0, 2, 4, 8, 12, 16 and 20 Gy. The clastogenic, cytotoxic, proliferative and clonogenic capacities and bystander effect were evaluated. In addition, we assessed survival and toxicity in a retrospective study of 49 patients with lung cancer. Our findings showed that the greater efficacy of ablative regimens should not only be attributed to events of direct cell death induced by genotoxic damage, but also to a lower cell repopulation and the indirect action of clastogenic factors secreted. These treatments were optimal in terms of 1- and 2-year overall survival (74 and 65%, respectively), and progression-free survival at 1 and 2 years (71 and 61%, respectively). The greater efficacy of high doses per fraction could be attributed to a multifactorial mechanism that goes beyond the 4Rs of conventional radiotherapy.

Radiosensitivity of radiotherapy patients: The effect of individual DNA repair capacity

Individual radiosensitivity is a critical problem in radiotherapy because of the treatment restrictions it imposes. We have tested whether induction/repair of genomic lesions correlates with the acute cutaneous effects of radiotherapy. Peripheral blood samples of 56 healthy volunteers and 18 patients with breast cancer were studied. DNA damage and DNA repair capacity were assessed in vitro (alkaline comet assay). Patients without skin reaction did not show significant differences from healthy individuals, with respect to either initial or radiation-induced DNA damage. Similar DNA repair kinetics, fitting a decreasing exponential response, were observed in both groups, and there were no significant differences in residual genotoxic damage. In contrast, patients exhibiting acute side effects showed significantly lower DNA repair ability and significantly more residual damage, compared to patients without radiotoxicity. This approach may help to identify patients who are at greater risk of radiotherapy side effects. However, many other factors, such as dosimetry, irradiated volume, and lifestyle should also be considered in the evaluation of individual radiosensitivity.

Protection Against Ionizing Radiation-Induced Normal Tissue Damage by Resveratrol: A Systematic Review

The use of some agents as radioprotectors has been evaluated for protection against normal tissue toxicity following exposure to ionizing radiation. Resveratrol, a natural flavonoid, with antioxidant and anti-inflammatory properties has attracted research interests for its radioprotective potential. This study systematically evaluates existing studies to examine the radioprotective effectiveness of resveratrol. A literature search of the electronic databases, including PubMed, Scopus, and Embase was conducted to retrieve articles investigating the protective effect of resveratrol against ionizing radiation-induced damage to normal tissues. The search timeframe ranged from the inception of each database to January 2020. From an initial search of 231 articles, and after the removal of duplicates as well as applying the predetermined inclusion and exclusion criteria, 33 articles were finally included for this systematic review. Results showed promising protective effect of resveratrol against ionizing radiation-induced damage to normal tissues. Furthermore, no adverse effect was observed after administering resveratrol. Resveratrol showed the potential to protect against ionizing radiation-induced damage to normal tissue cells via notable mechanisms, including anti-apoptotic and anti-inflammatory effects. However, further studies on the efficacy of clinical translation of resveratrol would open up more insights, while other gray areas such as the optimal radioprotective dosage of resveratrol requires further investigation. Overall, resveratrol is a potential double-edged sword in cancer therapy while protecting healthy tissues.

Modulation of ionizing radiation-induced damage in human blood lymphocytes by in vivo treatment with resveratrol

Purpose: Radiotherapy is an effective tool for cancer control, but side effects on normal tissue limit its therapeutic effectiveness. Thus, the search for agents that may allow the use of high doses of radiation but exerting a differential protection to healthy tissue is of current concern. Resveratrol (3,5,4'-trihydroxy-trans-stilbene) (RSV) is a polyphenol with pleiotropic benefits for health due to its antioxidant and anti-inflammatory properties. Recent findings suggest that RSV could be promising in the fight against cancer since it inhibits the growth of tumor cells and optimizes radiotherapy. However, evidence in rodents and human beings is inconsistent. The aim of this study was to evaluate the radiomodulatory capacity of RSV on human lymphocytes. Materials and methods: To study these properties of RSV, human peripheral blood lymphocytes from 20 healthy women undergoing in vivo RSV treatment with 50 mg/day doses were irradiated. The genotoxic damage was assessed by the comet assay, also called single cell gel electrophoresis (it makes it possible to measure the extent of the DNA migration from individual cells, detecting the genomic damage present in each cell). Results: No differences were observed in basal clastogenic damage among samples without irradiation. There was only a slight radiation-induced clastogenic damage. The damage index (DI) value had a statistically significant increase in the exposed groups in comparison with the control groups (p < .0001), but a statistically significant decrease of the DI value was observed in samples irradiated after treatment with RSV compared to pretreatment samples (p < .0001). Conclusion: The RSV used as a dietary supplement had radioprotective properties, without exerting a cytotoxic effect. The potential utility of RSV to optimize the radiotherapeutic ratio in cancer treatments using radiotherapy should be considered.

Leveraging the Cardio-Protective and Anticancer Properties of Resveratrol in Cardio-Oncology

Cardio-oncology is a clinical/scientific discipline which aims to prevent and/or treat cardiovascular diseases in cancer patients. Although a large number of cancer treatments are known to cause cardiovascular toxicity, they are still widely used because they are highly effective. Unfortunately, therapeutic interventions to prevent and/or treat cancer treatment-induced cardiovascular toxicity have not been established yet. A major challenge for such interventions is to protect the cardiovascular system without compromising the therapeutic benefit of anticancer medications. Intriguingly, the polyphenolic natural compound resveratrol and its analogs have been shown in preclinical studies to protect against cancer treatment-induced cardiovascular toxicity. They have also been shown to possess significant anticancer properties on their own, and to enhance the anticancer effect of other cancer treatments. Thus, they hold significant promise to protect the cardiovascular system and fight the cancer at the same time. In this review, we will discuss the current knowledge regarding the cardio-protective and the anticancer properties of resveratrol and its analogs. Thereafter, we will discuss the challenges that face the clinical application of these agents. To conclude, we will highlight important gaps of knowledge and future research directions to accelerate the translation of these exciting preclinical findings to cancer patient care.