Effects of topical timolol for the prevention of radiation-induced dermatitis in breast cancer: a pilot triple-blind, placebo-controlled trial

The effect of various interventions on the prevention of radiation dermatitis: a network meta-analysis

OBJECTIVE

High doses of radiation, while effective at destroying tumor tissues, also result in radiation dermatitis (RD) at irradiated sites, which is one of the most common complications in cancer radiotherapy. Currently, no standardized protocols for the prevention and treatment of RD have been established in clinical practices, and severe RD can compromise treatment efficacy and reduce patients' quality of life. This systematic review and network meta-analysis (NMA) aims to compare the effectiveness of various interventions in preventing RD in patients.

METHODS

As of June 2023, four databases, including PubMed, Embase, Web of Science, and the Cochrane Library, were searched, with a total of 19 interventions obtained for comparative analysis of their effectiveness in preventing RD. The Cochrane risk-of-bias tool was employed to screen literature, extract data, and appraise the quality of the studies by two researchers. Bayesian network meta-analysis (NMA) was conducted utilizing StataSE 15 and R 4.2.3.

RESULTS

A total of 33 studies involving 4307 patients were included in this analysis. From the 33 studies, 19 interventions, encompassing Barrier Films and Dressings (BFD), Boron_Gel, Best supportive care, Corticosteroids_cream, Doxepin_cream, Eau Thermale Avèn_gel, Epidermal Growth Factor_cream, Hyaluronan_cream, Medicinal_Plants, Mineral_Oil, Olive oil and calcium hydroxide (OOCH), Photobiomodulation therapy, Recove_cream, Silicone_gel, Silver sulfadiazine (SSD), Timolol_Gel, Trolamine, VitD_Gel, and VitE_Gel, were retrieved and compared. The NMA results indicated that Hyaluronan_cream (SUCRA: 94.9%) was highly effective in preventing Grade 0/1 RD. Meanwhile, OOCH (SUCRA: 95.7%) demonstrated the most prominent effect in preventing ≥ Grade 2 RD.

CONCLUSION

The study reveals that Hyaluronan_cream and OOCH are two promising treatments for the prevention of RD in patients undergoing radiotherapy. Future research might focus on validating the efficacy of these two therapies with large sample sizes and on identifying an optimal intervention strategy.

The Study on Timolol and Its Potential Phototoxicity Using Chemical, In Silico and In Vitro Methods

Timolol (TIM) is a non-selective ß-adrenergic receptor antagonist used orally for the treatment of hypertension and heart attacks, and topically for treating glaucoma; lately, it has also been used in some specific dermatological problems. In the present study, its photodegradation and potential risk of phototoxicity were examined using chemical, in silico and in vitro methods. The UV/VIS irradiated solutions of TIM at pH 1-13 were subjected to LC-UV and UPLC-HRMS/MS analyses showing pseudo first-order kinetics of degradation and several degradation products. The structures of these photodegradants were elucidated by fragmentation path analysis based on high resolution (HR) fragmentation mass spectra, and then used for toxicity evaluation using OSIRIS Property Explorer and Toxtree. Potential risk of phototoxicity was also studied using chemical tests for detecting ROS under UV/VIS irradiation and in vitro tests on BALB/c 3T3 mouse fibroblasts (MTT, NRU and Live/Dead tests). TIM was shown to be potentially phototoxic because of its UV/VIS absorptive properties and generation ROS during irradiation. As was observed in the MTT and NRU tests, the co-treatment of fibroblasts with TIM and UV/VIS light inhibited cell viability, especially when concentrations of the drug were higher than 50 µg/mL.

Mechanism and application of β-adrenoceptor blockers in soft tissue wound healing

Soft tissue damage stimulates sympathetic nerves to release large amounts of catecholamine hormones which bind to β-adrenergic receptors (β-ARs) on the cell membrane surface. It activates the downstream effector molecules and impairs soft tissue wound healing. β-blockers specifically inhibit β-ARs activation in acute/chronic skin lesions and ulcerative hemangiomas. They also accelerate soft tissue wound healing by shortening the duration of inflammation, speeding keratinocyte migration and reepithelialization, promoting wound contraction and angiogenesis, and inhibiting bacterial virulence effects. In addition, β-blockers shorten wound healing periods in patients with severe thermal damage by reducing the hypermetabolic response. While β-blockers promote/inhibit corneal epithelial cell regeneration and restores limbal stem/progenitor cells function, it could well accelerate/delay corneal wound healing. Given these meaningful effects, a growing number of studies are focused on examining the efficacy and safety of β-blockers in soft tissue wound repair, including acute and chronic wounds, severe thermal damage, ulcerated infantile hemangioma, corneal wounds, and other soft tissue disorders. However, an intensive investigation on their acting mechanisms is imperatively needed. The purpose of this article is to summerize the roles of β-blockers in soft tissue wound healing and explore their clinical applications.

The efficacy of medicinal plant preparations in the alleviation of radiodermatitis in patients with breast cancer: A systematic review of clinical trials

Radiodermatitis in breast cancer patients varies from mild irritation to life-threatening lesions. Several studies suggest a role for topical corticosteroid ointments in the treatment of radiodermatitis. Yet, to avoid the adverse effects of corticosteroids, many authors recommend the use of topical herbal products instead. The therapeutic role of herbal treatments has yet to be fully understood. This systematic review evaluates the role of topical or oral herbal medicines in radiodermatitis prevention and treatment. A systematic search of four databases (Embase, PubMed, Web of Science, and Scopus) was performed without language and time restrictions from their inception until April 2023. The bibliographies of potential articles were also searched manually. Studies evaluated and compared the effects of herbal preparations with the control group, on dermatitis induced by radiotherapy for breast cancer. The Cochrane risk of bias tool was used to assess the included studies. Thirty-five studies were included in the systematic review. Studies which used herbal drugs including topical and oral formulations were evaluated. Herbal monotherapy and combination therapy were reported, and their effects on radiodermatitis were explained in the systematic review. In conclusion, henna ointments, silymarin gel, and Juango cream were reported to reduce the severity of radiodermatitis. These agents should be considered for radiodermatitis prophylaxis and treatment. The data on aloe gel and calendula ointment were conflicting. Further randomized controlled trials of herbal medications and new herbal formulations are required to determine their effects on breast cancer radiodermatitis.