RESUMO
Radiobiology has evolved from a mechanistic model based on DNA damage and response factors into a more complex model that includes effects on the immune system and the tumor microenvironment (TME). Irradiation has an immunomodulatory effect that can manifest as increased anti-tumor immunity or immunosuppression. Irradiation promotes an inflammatory microenvironment through the release of pro-inflammatory cytokines and endothelial damage, which recruit immune system cells to the irradiated area. Radiation-induced immunogenic cell death (ICD), characterized by the release of damage-associated molecular patterns (DAMPs) and tumor antigens, triggers an anti-tumor immune response of both innate and adaptive immunity. Anti-tumor immunity can manifest at a distance from the irradiated area, a phenomenon known as the abscopal effect (AE), which involves dendritic cells and CD8+ T cells. Irradiation also produces an immunosuppressive effect mediated by tumor-associated macrophages (TAMs) and regulatory T lymphocytes (Tregs), which counterbalances the immunostimulatory effect. In this work, we review the mechanisms involved in the radiation-induced immune response, which support the combined treatment of RT and immunotherapy, focusing, where possible, on gynecologic cancer.
RESUMO
INTRODUCTION: The purpose of this multicenter, prospective, observational, open-label study was to evaluate the use and tolerability of dermo-cosmetic products in preventing skin reactions associated with cancer treatments. PATIENTS AND METHODS: A 12-product kit was supplied to patients before chemotherapy began and was to be used throughout the treatment phase. Cutaneous adverse events were evaluated at each treatment session. Physicians evaluated skin reactions (edema, erythema, dryness, desquamation, pigmentation disorders, and cracks) and gave their opinion on the skin benefit for patients at the end of the study. Patients also evaluated the product benefit using the Patient Benefit Index (PBI) questionnaire. Results were analyzed by subgroups of casual and regular users, based on number and frequency of products used. RESULTS: A total of 147 patients were enrolled in cancer services in Germany, France, Italy, Spain, and Canada. Mean age was 59 years with 71% being female. Product tolerance on whole body was rated good to excellent for at least 89% of the patients for each product. Aggravated skin reactions during the study were reported more frequently by casual users than regular users (39.5% versus 22%; p=0.029). Similarly, casual users reported more erythema aggravation (p=0.02) and desquamation (p=0.03) than regular users. PBI >1 was reported for 95.5% of patients and regular users had significantly higher scores than casual users (p=0.049). DISCUSSION: Overall, the 12-product kit was very well tolerated, with regular users reporting benefits more frequently than casual users. Results support international recommendations to use appropriate skin care products to minimize the impact of cutaneous reactions associated with chemotherapy.
RESUMO
The p38 Mitogen Activated Protein Kinase (MAPK) signaling pathway has become a major player in the response to DNA-damage. A growing body of evidences has been relating this signaling pathway to the cellular response to ionizing radiation (IR), suggesting a role in radioresistance. Here, we study the implication of this signaling pathway in the response to IR in terms of radioresistance. To this end we used 10 different cell lines derived from several types of tumors (colorectal, non-small cell lung cancer -NSCLC-, renal and glioblastoma). Although p38 MAPK is transiently activated by IR, our data, obtained by genetic and chemical approaches, showed that this signaling pathway is not implicated in cellular viability after IR exposure. Indeed, down-modulation of this signaling pathway promotes a mild radiosensitivity depending on the cell line. However, it is remarkable that lack of p38 MAPK α abrogates the radiosensitizing effect of 5-Fluorouracil (5-FU) in HCT116 cell line, supporting the role of this MAPK in the radiosensitizing action of 5-FU.