Effect of basic fibroblast growth factor on radiation-induced oral mucositis in male Syrian hamsters

Evaluation of the efficacy of the anti-ulcer oral mucosal protective agent RADoralex® in the prevention and treatment of radiation-induced oral mucosal reactions induced during treatment of nasopharyngeal carcinoma

The aim of this study was to evaluate the efficacy and safety of antiulcer oral mucosal protectant-RADoralex® in the prevention and treatment of radiation-induced oral mucosal reactions elicited during intensity-modulated radiation therapy (IMRT). for locally advanced nasopharyngeal carcinoma (NPC). A total of 90 patients with locally advanced NPC who developed post-treatment grade 1 oral mucositis were selected for this study. They were randomly assigned to the experimental group (n = 44) treated by mouth rinsing with the RADoralex® during radiochemotherapy and the control group (n = 43) treated by mouth rinsing with sodium bicarbonate solution, and the patients’ oral mucosal conditions, quality of life, weight change and oral pain levels were analyzed. The incidence of Common Terminology Criteria for Adverse Events (CTCAE) v4.0 grade 2 and grade 3 oral mucositis were significantly lower in the experimental group than in the control group. Compared to the control group, the time to progression, and the time from the end of treatment to oral mucosa healing in the experimental group was significantly shorter. The experimental group lost 8.66 ± 3.543% of their body weight during treatment period, while the control group lost 12.53 ± 4.284% (p < .001). From the beginning the 3^rd week of treatment to the 2^nd week after the end of treatment, the Oral Mucositis Assessment Scale (OMAS) scores were lower in the experimental group than in the control group (p < .05). RADoralex® significantly reduced the incidence and severity of oral mucositis in patients with locally advanced NPC during radiochemotherapy, delayed the progression of oral mucositis.

Saving normal tissues - a goal for the ages

Almost since the earliest utilization of ionizing radiation, many within the radiation community have worked toward either preventing (i.e. protecting) normal tissues from unwanted radiation injury or rescuing them from the downstream consequences of exposure. However, despite over a century of such investigations, only incremental gains have been made toward this goal and, with certainty, no outright panacea having been found. In celebration of the 60th anniversary of the International Journal of Radiation Biology and to chronicle the efforts that have been made to date, we undertook a non-rigorous survey of the articles published by normal tissue researchers in this area, using those that have appeared in the aforementioned journal as a road map. Three 'snapshots' of publications on normal tissue countermeasures were taken: the earliest (1959-1963) and most recent (2013-2018) 5-year of issues, as well as a 5-year intermediate span (1987-1991). Limiting the survey solely to articles appearing within International Journal of Radiation Biology likely reduced the number of translational studies interrogated given the basic science tenor of this particular publication. In addition, by taking 'snapshots' rather than considering the entire breadth of the journal's history in this field, important papers that were published during the interim periods were omitted, for which we apologize. Nonetheless, since the journal's inception, we observed that, during the chosen periods, the majority of studies undertaken in the field of normal tissue countermeasures, whether investigating radiation protectants, mitigators or treatments, have focused on agents that interfere with the physical, chemical and/or biological effects known to occur during the acute period following whole body/high single dose exposures. This relatively narrow approach to the reduction of normal tissue effects, especially those that can take months, if not years, to develop, seems to contradict our growing understanding of the progressive complexities of the microenvironmental disruption that follows the initial radiation injury. Given the analytical tools now at our disposal and the enormous benefits that may be reaped in terms of improving patient outcomes, as well as the potential for offering countermeasures to those affected by accidental or mass casualty exposures, it appears time to broaden our approaches to developing normal tissue countermeasures. We have no doubt that the contributors and readership of the International Journal of Radiation Biology will continue to contribute to this effort for the foreseeable future.

Genetic modification to induce CXCR2 overexpression in mesenchymal stem cells enhances treatment benefits in radiation-induced oral mucositis

Radiation-induced oral mucositis affects patient quality of life and reduces tolerance to cancer therapy. Unfortunately, traditional treatments are insufficient for the treatment of mucositis and might elicit severe side effects. Due to their immunomodulatory and anti-inflammatory properties, the transplantation of mesenchymal stem cells (MSCs) is a potential therapeutic strategy for mucositis. However, systemically infused MSCs rarely reach inflamed sites, impacting their clinical efficacy. Previous studies have demonstrated that chemokine axes play an important role in MSC targeting. By systematically evaluating the expression patterns of chemokines in radiation/chemical-induced oral mucositis, we found that CXCL2 was highly expressed, whereas cultured MSCs negligibly express the CXCL2 receptor CXCR2. Thus, we explored the potential therapeutic benefits of the transplantation of CXCR₂-overexpressing MSCs (MSCs^CXCR2) for mucositis treatment. Indeed, MSCs^CXCR2 exhibited enhanced targeting ability to the inflamed mucosa in radiation/chemical-induced oral mucositis mouse models. Furthermore, we found that MSC^CXCR2 transplantation accelerated ulcer healing by suppressing the production of pro-inflammatory chemokines and radiogenic reactive oxygen species (ROS). Altogether, these findings indicate that CXCR2 overexpression in MSCs accelerates ulcer healing, providing new insights into cell-based therapy for radiation/chemical-induced oral mucositis.