Acute and Chronic Cutaneous Reactions to Ionizing Radiation Therapy

Molecular biological mechanisms of radiotherapy-induced skin injury occurrence and treatment

Radiotherapy-Induced Skin Injury (RISI) is radiation damage to normal skin tissue that primarily occurs during tumor Radiotherapy and occupational exposure. The risk of RISI is high due to the fact that the skin is not only the first body organ that ionizing radiation comes into contact with, but it is also highly sensitive to it, especially the basal cell layer and capillaries. Typical clinical manifestations of RISI include erythema, dry desquamation, moist desquamation, and ulcers, which have been established to significantly impact patient care and cancer treatment. Notably, our current understanding of RISI's pathological mechanisms and signaling pathways is inadequate, and no standard treatments have been established. Radiation-induced oxidative stress, inflammatory responses, fibrosis, apoptosis, and cellular senescence are among the known mechanisms that interact and promote disease progression. Additionally, radiation can damage all cellular components and induce genetic and epigenetic changes, which play a crucial role in the occurrence and progression of skin injury. A deeper understanding of these mechanisms and pathways is crucial for exploring the potential therapeutic targets for RISI. Therefore, in this review, we summarize the key mechanisms and potential treatment methods for RISI, offering a reference for future research and development of treatment strategies.

Radiation dermatitis in the hairless mouse model mimics human radiation dermatitis

Over half of all people diagnosed with cancer receive radiation therapy. Moderate to severe radiation dermatitis occurs in most human radiation patients, causing pain, aesthetic distress, and a negative impact on tumor control. No effective prevention or treatment for radiation dermatitis exists. The lack of well-characterized, clinically relevant animal models of human radiation dermatitis contributes to the absence of strategies to mitigate radiation dermatitis. Here, we establish and characterize a hairless SKH-1 mouse model of human radiation dermatitis by correlating temporal stages of clinical and pathological skin injury. We demonstrate that a single ionizing radiation treatment of 30 Gy using 6 MeV electrons induces severe clinical grade 3 peak toxicity at 12 days, defined by marked erythema, desquamation and partial ulceration, with resolution occurring by 25 days. Histopathology reveals that radiation-induced skin injury features temporally unique inflammatory changes. Upregulation of epidermal and dermal TGF-ß1 and COX-2 protein expression occurs at peak dermatitis, with sustained epidermal TGF-ß1 expression beyond resolution. Specific histopathological variables that remain substantially high at peak toxicity and early clinical resolution, including epidermal thickening, hyperkeratosis and dermal fibroplasia/fibrosis, serve as specific measurable parameters for in vivo interventional preclinical studies that seek to mitigate radiation-induced skin injury.

Upregulation of PRRX2 by silencing Marveld3 as a protective mechanism against radiation-induced ferroptosis in skin cells

BACKGROUND

Radiation-induced skin injury (RISI) represents a significant complication in patients receiving radiotherapy and individuals exposed to nuclear accidents, characterized by a protracted wound-healing process relative to injuries from other etiologies. Current preventive and management approaches remain inadequate. Consequently, investigating efficacious intervention strategies that target the disease's progression characteristics holds significant practical importance.

METHODS

Small interfering RNA (siRNA) and overexpression plasmid were used to modulate the expression of Marvel domain containing 3 (Marveld3) and paired related homeobox 2 (PRRX2). Protein and mRNA levels were estimated by Western Blot and real-time PCR, respectively. Intracellular levels of Malondialdehyde (MDA), a terminal product of lipid peroxidation, were measured following the manufacturer's protocol for MDA assay kit. Similarly, intracellular levels of ferrous iron (Fe2+) and reactive oxygen species (ROS) were determined using their respective assay kits. Lipid peroxidation status within the cells was evaluated via BODIPY staining. Immunohistochemistry was conducted to ascertain the expression of PRRX2 in skin tissues collected at various time points following irradiation of rats. The H-score method was used to evaluate the percentage of positively stained cells and staining intensity. RNA sequencing, Gene Ontology (GO) analysis, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were conducted by OE Biotech Company.

RESULTS

In this study, our findings indicated that Marveld3 suppression could effectively inhibit lipid peroxidation levels in irradiated skin cells, concomitantly reducing intracellular Fe2+ content. Additionally, the silencing of Marveld3 effectively abrogated the impact of a ferroptosis agonist on cellular viability, resulting in the upregulation of 66 and 178 genes, as well as the downregulation of 188 and 31 genes in irradiated HaCaT and WS1 cells, respectively. Among the differentially expressed genes, the PRRX2 which was found to be involved in the process of ferroptosis, exhibited statistically significant upregulation. And the upregulation of PRRX2 expression may attenuate radiation-induced lipid peroxidation in skin cells, thereby functioning as a potential stress-responsive mechanism to counteract radiation effects.

CONCLUSIONS

This study elucidates the role of Marveld3 in radiation-induced ferroptosis in skin cells. Inhibition of Marveld3 led to the upregulation of PRRX2, which subsequently resulted in a reduction of Fe2+ and ROS levels, as well as the suppression of lipid peroxidation. These effects collectively mitigated the occurrence of ferroptosis.

Effects of photobiomodulation therapy for acute radiation dermatitis in patients with cancer: A systematic review and meta‑analysis of real-world evidence

PURPOSE

To examine the effectiveness of photobiomodulation therapy (PBMT) for acute radiation dermatitis (ARD) in patients with cancer.

MATERIALS AND METHODS

PubMed, Embase, Cochrane Library, and CINAHL were searched for articles published between database inception until July 2024. Randomized controlled trials (RCTs) and non-RCTs examining the effects of PBMT against ARD in patients with cancer were included for analysis. A random-effects model was used to conduct meta-analyses and sensitivity analyses. Subgroup analyses were conducted for cancer types and PBMT goals (prevention or treatment of ARD) with stratification for different grades of ARD.

RESULTS

Eight studies (five RCTs and three non-RCTs) were included in this meta-analysis. Compared with the control group, the PBMT group exhibited significantly lower ARD incidence at grades 2 and 3 (risk difference =  - 0.36, 95 % confidence interval =  - 0.53 to - 0.19, I2 = 85 %, P = < 0.00001). Subgroup analyses revealed that, compared with the control group, PBMT had a significant effect on both breast cancer and head and neck cancer. In addition, PBMT significantly reduced grades 2 and 3 ARD incidence in the PBMT group for both prevention and treatment subgroups.

CONCLUSION

PBMT may have beneficial effects on the prevention and treatment of higher-grade ARD in patients with breast cancer and head and neck cancer. Nevertheless, the studies included in this meta-analysis exhibited high heterogeneity. Therefore, the results must be interpreted with caution.

Radiation-induced skin reactions: oxidative damage mechanism and antioxidant protection

According to official statistics, cancer remains the main reason of death and over 50% of patients with cancer receive radiotherapy. However, adverse consequences after radiation exposure like radiation-induced skin reactions (RISR) have negative or even fatal impact on patients' quality of life (QoL). In this review we summarize the mechanisms and managements of RISRs, a process that involve a variety of extracellular and intracellular signals, among which oxidative stress (OS) are now commonly believed to be the initial part of the occurrence of all types of RISRs. As for the management of RISRs, traditional treatments have been widely used but without satisfying outcomes while some promising therapeutic strategies related to OS still need further researches. In the context we discuss how OS leads to the happening of RISRs of different types, hoping it can shed some light on the exploration of new countermeasures.

Facile fabrications of poly (acrylic acid)-mesoporous zinc phosphate/polydopamine Janus nanoparticles as a biosafe photothermal therapy agent and a pH/NIR-responsive drug carrier

Balancing biocompatibility and drug-loading efficiency in nanoparticles presents a significant challenge. In this study, we describe the facile fabrication of poly (acrylic acid)-mesoporous zinc phosphate/polydopamine (PAA-mZnP/PDA) Janus nanoparticles (JNPs). The PDA half-shell itself can serve as a photothermal agent for photothermal therapy (PTT), as well as to offers sites for polyethylene glycol (PEG) to enhance biocompatibility. Concurrently, the mesoporous ZnP core allows high loading of doxorubicin (DOX) for chemotherapy and the Cy5.5 dye for fluorescence imaging. The resultant PAA-mZnP/PDA-PEG JNPs exhibit exceptional biocompatibility, efficient drug loading (0.5 mg DOX/1 mg JNPs), and dual pH/NIR-responsive drug release properties. We demonstrate the JNPs' satisfactory anti-cancer efficacy, highlighting the synergistic effects of chemotherapy and PTT. Furthermore, the potential for synergistic fluorescence imaging-guided chemo-phototherapy in cancer treatment is illustrated. Thus, this work exemplifies the development of biosafe, multifunctional JNPs for advanced applications in cancer theranostics. STATEMENT OF SIGNIFICANCE: Facile fabrication of monodispersed nanomedicine with multi-cancer killing modalities organically integrated is nontrivial and becomes more challenging under the biocompatibility requirement that is necessary for the practical applications of nanomedicines. In this study, we creatively designed PAA-mZnP/PDA JNPs and fabricated them under mild conditions. Our method reliably yields uniform JNPs with excellent monodispersity. To maximize functionalities, we achieve fourfold advantages including efficient drug/fluorescent dye loading, PTT, pH/NIR dual-responsive properties, and optimal biocompatibility. The as-fabricated JNPs exhibit satisfactory anti-cancer performance both in vitro and in vivo, and demonstrate the potential of JNPs in fluorescence imaging-guided synergistic cancer chemo-phototherapy. Overall, our research establishes a pathway in versatile inorganic/polymer JNPs for enhanced cancer diagnosis and therapy.

Barrier films or dressings for the prevention of acute radiation dermatitis in breast cancer: a systematic review and network meta-analysis

BACKGROUND

Barrier films or dressings were reported to be effective in preventing radiation dermatitis (RD) in breast cancer patients, but their comparative efficacy is unknown.

METHODS

A systematic literature search was performed on Embase, MEDLINE and Cochrane CENTRAL Registry of Clinical Trials from inception to October 20, 2023. Randomised controlled trials (RCTs) comparing barrier films or dressings to the standard of care (SOC) or other interventions were included. We estimated summary odds ratios and mean differences using network meta-analysis with random effects. This study was registered with PROSPERO (ID: CRD42023475021).

RESULTS

Fourteen RCTs met inclusion criteria. Six interventions were analysed: 3M™ Moisturizing Double Barrier Cream (MDBC), 3M™ No Sting Barrier Film (BF), Hydrofilm® (HF), Mepitel® Film (MF), Silver Leaf Nylon Dressing and StrataXRT®. HF, MF and StrataXRT® reduced the incidence of moist desquamation compared to SOC (HF: OR = 0.08; p = 0.02; MF: OR = 0.31 p < 0.01; StrataXRT®: OR = 0.22, p = 0.04). The ranking of agents from most to least effective in preventing moist desquamation according to P-scores was HF (92.5%), MF (78.5%), StrataXRT® (70.1%), BF (46.4%), Silver Leaf Nylon Dressing (24.9%), MDBC (22.9%) and SOC (14.7%). Only four RCTs on HF and MF included patient-reported outcome (PRO) assessments that allowed pooling for analysis. HF and MF were more effective in reducing pain, itchiness and burning sensation compared to SOC (p < 0.01 for all symptoms).

CONCLUSION

HF and MF were effective in preventing RD in breast cancer. Future RCTs should compare these interventions to effective cream preparations, such as topical corticosteroids.

Adipose-derived stem cells apoptosis rejuvenate radiation-impaired skin in mice via remodeling and rearranging dermal collagens matrix

BACKGROUND

Chronic radiation dermatitis (CRD) is a late consequence of radiation with high incidence in patients receiving radiotherapy. Conventional therapies often yield unsatisfactory results. Therefore, this study aimed to explore the therapeutic potential and mechanism of adipose-derived stem cells (ADSCs) for CRD, paving the way for novel regenerative therapies in clinical practice.

METHODS

Clinical CRD skin biopsies were analyzed to character the pathological changes of CRD skin and guided the animal modeling scheme. Subsequently, an in vivo analysisusing mouse CRD models was conducted to explore their effects of ADSCs on CRD, monitoring therapeutic impact for up to 8 weeks. Transcriptome sequencing and histologic sections analysis were performed to explore the potential therapeutic mechanism of ADSCs. Following observing extensive apoptosis of transplanted ADSCs, the therapeutic effect of ADSCs were compared with those of apoptosis-inhibited ADSCs. Multiphoton imaging and analysis of collagen morphologic features were employed to explain how translated ADSCs promote collagen remodeling at the microscopic level based on the contrast of morphology of collagen fibers.

RESULTS

Following injection into CRD-afflicted skin, ADSCs therapy effectively mitigated symptoms of CRD, including acanthosis of the epidermis, fibrosis, and irregular collagen deposition, consistent with the possible therapeutic mechanism suggested by transcriptome sequencing. Notably, in vivo tracking revealed a significant reduction in ADSCs number due to extensive apoptosis. Inhibiting apoptosis in ADSCs partially tempered their therapeutic effects. Mechanically, analysis of collagen morphologic features indicated that translated ADSCs might promote dermal extracellular matrix remodeling through enlarging, lengthening, crimping, and evening collagen, counteracting the atrophy and rupture caused by irradiation.

CONCLUSIONS

This study demonstrated that ADSCs underwent substantial apoptosis upon local skin transplantation, and paradoxically, this apoptosis is essential for their efficacy in promoting the regeneration of late radiation-impaired skin. Mechanically, transplanted ADSCs could promote the remodeling and rearrangement of radiation-damaged dermal collagen matrix.

Multifunctional carbomer based ferulic acid hydrogel promotes wound healing in radiation-induced skin injury by inactivating NLRP3 inflammasome

BACKGROUND

Radiation-induced skin injury is a significant adverse reaction to radiotherapy. However, there is a lack of effective prevention and treatment methods for this complication. Ferulic acid (FA) has been identified as an effective anti-radiation agent. Conventional administrations of FA limit the reaching of it on skin. We aimed to develop a novel FA hydrogel to facilitate the use of FA in radiation-induced skin injury.

METHODS

We cross-linked carbomer 940, a commonly used adjuvant, with FA at concentrations of 5%, 10%, and 15%. Sweep source optical coherence tomography system, a novel skin structure evaluation method, was applied to investigate the influence of FA on radiation-induced skin injury. Calcein-AM/PI staining, CCK8 assay, hemolysis test and scratch test were performed to investigate the biocompatibility of FA hydrogel. The reducibility of DPPH and ABTS radicals by FA hydrogel was also performed. HE staining, Masson staining, laser Doppler blood flow monitor, and OCT imaging system are used to evaluate the degree of skin tissue damage. Potential differentially expressed genes were screened via transcriptome analysis.

RESULTS

Good biocompatibility and in vitro antioxidant ability of the FA hydrogels were observed. 10% FA hydrogel presented a better mechanical stability than 5% and 15% FA hydrogel. All three concentrations of FA remarkably promoted the recovery of radiation-induced skin injury by reducing inflammation, oxidative conidiation, skin blood flow, and accelerating skin tissue reconstruction, collagen deposition. FA hydrogel greatly inhibiting the levels of NLRP3, caspase-1, IL-18, pro-IL-1β and IL-1β in vivo and vitro levels through restraining the activation of NLRP3 inflammasome. Transcriptome analysis indicated that FA might regulate wound healing via targeting immune response, inflammatory response, cell migration, angiogenesis, hypoxia response, and cell matrix adhesion.

CONCLUSIONS

These findings suggest that the novel FA hydrogel is a promising therapeutic method for the prevention and treatment of radiation-induced skin injury patients.

A comprehensive review on the potential of coumarin and related derivatives as multi-target therapeutic agents in the management of gynecological cancers

Current treatments for gynecological cancers include surgery, radiotherapy, and chemotherapy. However, these treatments often have significant side effects. Phytochemicals, natural compounds derived from plants, offer promising anticancer properties. Coumarins, a class of benzopyrone compounds found in various plants like tonka beans, exhibit notable antitumor effects. These compounds induce cell apoptosis, target PI3K/Akt/mTOR signaling pathways, inhibit carbonic anhydrase, and disrupt microtubules. Additionally, they inhibit tumor multidrug resistance and angiogenesis and regulate reactive oxygen species. Specific coumarin derivatives, such as auraptene, praeruptorin, osthole, and scopoletin, show anti-invasive, anti-migratory, and antiproliferative activities by arresting the cell cycle and inducing apoptosis. They also inhibit metalloproteinases-2 and -9, reducing tumor cell migration, invasion, and metastasis. These compounds can sensitize tumor cells to radiotherapy and chemotherapy. Synthetic coumarin derivatives also demonstrate potent antitumor and anticancer activities with minimal side effects. Given their diverse mechanisms of action and minimal side effects, coumarin-class phytochemicals hold significant potential as therapeutic agents in gynecological cancers, potentially improving treatment outcomes and reducing side effects. This review will aid in the synthesis and development of novel coumarin-based drugs for these cancers.

Single-cell RNA-Seq analysis of molecular changes during radiation-induced skin injury: the involvement of Nur77

Introduction: Ionizing radiation has been widely used in industry, medicine, military and agriculture. Radiation-induced skin injury is a significant concern in the context of radiotherapy and accidental exposure to radiation. The molecular changes at the single-cell level and intercellular communications during radiation-induced skin injury are not well understood. Methods: This study aims to illustrate this information in a murine model and human skin samples from a radiation accident using single-cell RNA sequencing (scRNA-Seq). We further characterize the functional significance of key molecule, which may provide a potential therapeutic target. ScRNA-Seq was performed on skin samples from a nuclear accident patient and rats exposed to ionizing radiation. Bioinformatic tools were used to analyze the cellular heterogeneity and preferential mRNAs. Comparative analysis was performed to identify dysregulated pathways, regulators, and ligand-receptor interactions in fibroblasts. The function of key molecule was validated in skin cells and in three mouse models of radiation-induced skin injury. Results: 11 clusters in human skin and 13 clusters of cells in rat skin were depicted respectively. Exposure to ionizing radiation caused changes in the cellular population (upregulation of fibroblasts and endothelial cells, downregulation of keratinocytes). Fibroblasts and keratinocytes possessed the most interaction pairs with other cell lineages. Among the five DEGs common to human and rat skins, Nur77 was highly expressed in fibroblasts, which mediated radiosensitivity by cell apoptosis and modulated crosstalk between macrophages, keratinocytes and endothelial cells in radiation-induced skin injury. In animal models, Nur77 knock-out mice (Nur77 -/-) showed more severe injury after radiation exposure than wild-type counterparts in three models of radiation-induced skin injury with complex mechanisms. Conclusion: The study reveals a single-cell transcriptional framework during radiation-induced skin injury, which provides a useful resource to uncover key events in its progression. Nur77 is a novel target in radiation-induced skin injury, which provides a potential therapeutic strategy against this disease.

Unravelling the success of transferosomes against skin cancer: Journey so far and road ahead

Skin cancer remains one of the most prominent types of cancer. Melanoma and non-melanoma skin cancer are commonly found together, with melanoma being the more deadly type. Skin cancer can be effectively treated with chemotherapy, which mostly uses small molecular medicines, phytoceuticals, and biomacromolecules. Topical delivery of these therapeutics is a non-invasive way that might be useful in effectively managing skin cancer. Different skin barriers, however, presented a major obstacle to topical cargo administration. Transferosomes have demonstrated significant potential in topical delivery by improving cargo penetration through the circumvention of diverse skin barriers. Additionally, the transferosome-based gel can prolong the residence of drug on the skin, lowering the frequency of doses and their associated side effects. However, the choice of appropriate transferosome compositions, such as phospholipids and edge activators, and fabrication technique are crucial for achieving improved entrapment efficiency, penetration, and regulated particle size. The present review discusses skin cancer overview, current treatment strategies for skin cancer and their drawbacks. Topical drug delivery against skin cancer is also covered, along with the difficulties associated with it and the importance of transferosomes in avoiding these difficulties. Additionally, a summary of transferosome compositions and fabrication methods is provided. Furthermore, topical delivery of small molecular drugs, phytoceuticals, and biomacromolecules using transferosomes and transferosomes-based gel in treating skin cancer is discussed. Thus, transferosomes can be a significant option in the topical delivery of drugs to manage skin cancer efficiently.

Copper homeostasis and cuproptosis in radiation-induced injury

Radiation therapy for cancer treatment brings about a series of radiation injuries to normal tissues. In recent years, the discovery of copper-regulated cell death, cuproptosis, a novel form of programmed cell death, has attracted widespread attention and exploration in various biological functions and pathological mechanisms of copper metabolism and cuproptosis. Understanding its role in the process of radiation injury may open up new avenues and directions for exploration in radiation biology and radiation oncology, thereby improving tumor response and mitigating adverse reactions to radiotherapy. This review provides an overview of copper metabolism, the characteristics of cuproptosis, and their potential regulatory mechanisms in radiation injury.

Histological and Molecular Biological Changes in Canine Skin Following Acute Radiation Therapy-Induced Skin Injury

Radiation therapy is a crucial cancer treatment, but it can damage healthy tissues, leading to side effects like skin injuries and molecular alterations. This study aimed to elucidate histological and molecular changes in canine skin post-radiation therapy (post-RT) over nine weeks, focusing on inflammation, stem cell activity, angiogenesis, keratinocyte regeneration, and apoptosis. Four male beagles received a cumulative radiation dose of 48 Gy, followed by clinical observations, histological examinations, and an RT-qPCR analysis of skin biopsies. Histological changes correlated with clinical recovery from inflammation. A post-RT analysis revealed a notable decrease in the mRNA levels of Oct4, Sox2, and Nanog from weeks 1 to 9. VEGF 188 levels initially saw a slight increase at week 1, but they had significantly declined by week 9. Both mRNA and protein levels of COX-2 and Keratin 10 significantly decreased over the 9 weeks following RT, although COX-2 expression surged in the first 2 weeks, and Keratin 10 levels increased at weeks 4 to 5 compared to normal skin. Apoptosis peaked at 2 weeks and diminished, nearing normal by 9 weeks. These findings offer insights into the mechanisms of radiation-induced skin injury and provide guidance for managing side effects in canine radiation therapy.

Global hotspots and research trends of radiation-induced skin injury: a bibliometric analysis from 2004 to 2023

Background

Radiation therapy has become an important treatment for many malignant tumours after surgery and for palliative tumour care. Although modern radiotherapy technology is constantly improving, radiation damage to normal tissues is often difficult to avoid, and radiation-induced skin injury (RSI) is a common complication, manifested as skin erythema, peeling, ulceration, and even bone and deep organ damage, seriously affect the quality of life for patients. Basic research and clinical trials related to RSI have achieved certain results, while no researchers have conducted comprehensive bibliometric studies.

Objective

A comprehensive bibliometric analysis of publications on RSI published between 2004 and 2023 was conducted to identify current hotspots and future directions in this area of study.

Methods

RSI-related publications published between January 1, 2004, and December 31, 2023, were retrieved from the Web of Science Core Collection (WoSCC) database for analysis using VOSviewer and CiteSpace analytics.

Results

A total of 1009 publications on RSI from 2004 to 2023 were included in the WoSCC database. The United States had the highest productivity with 299 papers, accounting for 29.63% of the total production, followed by China with 193 papers (19.13%) and Japan with 111 papers (11.00%). In terms of research institutions and journals, the University of Toronto and Journal of Supportive Care in Cancer published the highest number of papers. Professor Edward Chow published the most articles, while Professor Shuyu Zhang was the most cited. The top ten most-cited papers focused on the pathogenesis, prevention, and management of RSI. Keyword co-occurrence analysis and the top 25 keywords with the strongest citation bursts suggest that current research focuses on the pathogenesis, prevention, and treatment management of RSI.

Conclusion

This study conducted a systematic bibliometric analysis of RSI publications from 2004 to 2023; identified the trends in RSI publications, major research countries, major research institutions, major research journals, major research authors, and major research keywords; and revealed the future development direction and research hotspots of this field. This study provides a valuable reference for future RSI research.

Antioxidants Hydroxytyrosol and Thioredoxin-Mimetic Peptide CB3 Protect Irradiated Normal Tissue Cells

Reducing side effects in non-cancerous tissue is a key aim of modern radiotherapy. Here, we assessed whether the use of the antioxidants hydroxytyrosol (HT) and thioredoxin-mimetic peptide CB3 (TMP) attenuated radiation-induced normal tissue toxicity in vitro. We used primary human umbilical vein endothelial cells (HUVECs) and human epidermal keratinocytes (HaCaT) as normal tissue models. Cells were treated with HT and TMP 24 h or immediately prior to irradiation. Reactive oxygen species (ROS) were assessed via luminescent- and fluorescence-based assays, migration was investigated using digital holographic microscopy, and clonogenic survival was quantified by colony formation assays. Angiogenesis and wound healing were evaluated via time-dependent microscopy. Secreted cytokines were validated in quantitative polymerase chain reaction (qPCR) studies. Treatment with HT or TMP was well tolerated by cells. The application of either antioxidant before irradiation resulted in reduced ROS formation and a distinct decrease in cytokines compared to similarly irradiated, but otherwise untreated, controls. Antioxidant treatment also increased post-radiogenic migration and angiogenesis while accelerating wound healing. HT or TMP treatment immediately before radiotherapy increased clonogenic survival after radiotherapy, while treatment 24 h before radiotherapy enhanced baseline proliferation. Both antioxidants may decrease radiation-induced normal tissue toxicity and deserve further pre-clinical investigation.

Mepitel film for the prevention of radiation dermatitis: A comprehensive review of its efficacy, side effects, physics measurements, patient- and clinician-reported outcomes

Objective

This review aimed to summarize the benefits, side effects, physics measurements, and patient- and clinician-reported outcomes of Mepitel film (MF) in preventing radiation dermatitis (RD) for cancer patients.

Methods

The online database PubMed was searched from inception to April 15, 2024 with the search terms "Mepitel film" or "Mepitel." Articles of any study design evaluating MF for the prevention of RD were included. Non-human studies were excluded.

Results

The database search identified 119 articles and 13 of them were included in this review. Across these studies, MF was found to be beneficial in reducing RD and improved patient- and clinician-reported outcomes in breast and head and neck cancers. Side effects of MF included itchiness, acne, allergic reaction, tightness, discomfort, and poor film adherence, but patient dropouts were uncommon. MF did not cause a bolus effect or increased skin dose in physics measurements.

Conclusions

MF is a safe and effective intervention for preventing acute RD. It should be recommended in breast cancer patients where the data is more robust. Further research is needed to evaluate MF's efficacy on patients with different skin tones, its cost-effectiveness, and identifying patients who most benefit from MF relative to other effective interventions.

Self-Crosslinking AuNPs Composite Hydrogel Bolus for Radiophotothermal Therapy

Radiophotothermal therapy is a promising treatment for superficial tumors. Traditional radiotherapy requires tissue boluses on the patient's skin to increase therapeutic effectiveness due to the dose-buildup effect of high-energy radiation. However, combining radiotherapy with photothermal therapy leads to uncertainties as the low-penetration near-infrared light dose is reduced after penetrating the bolus. To enhance precision and effectiveness, this study introduces a novel bolus made of AuNPs@poly(AM-THMA-DMAEMA) composite hydrogel. This hydrogel is prepared through a one-pot method involving the reduction of trihydrate chloroauric acid (HAuCl4·3H2O) and copolymerization of acrylamide (AM) and N-[Tris(hydroxymethyl)methyl]acrylamide (THMA) in a redox system with dimethylaminoethyl methacrylate (DMAEMA) and potassium persulfate (KPS). The gold nanoparticles (AuNPs) improve the mechanical strength (tensile strength of 320.84 kPa, elongation at break of 830%) and antibacterial properties (>99% against Staphylococcus aureus). The local surface plasmon resonance (LSPR) effect of AuNPs enables the hydrogel to absorb near-infrared light for precise monitoring of the infrared radiation dose. The hydrogel's biocompatibility is enhanced by the absence of additional crosslinking agents, and its excellent surface adhesion strength is due to numerous hydrogen bonds and electrostatic interactions. This study offers new possibilities for nanoparticle composite hydrogels as tissue boluses, achieving high precision and efficiency in radiophotothermal therapy.

Management of Skin Toxicities in Cancer Treatment: An Australian/New Zealand Perspective

Cancer systemic therapeutics and radiotherapy are often associated with dermatological toxicities that may reduce patients' quality of life and impact their course of cancer treatment. These toxicities cover a wide range of conditions that can be complex to manage with increasing severity. This review provides details on twelve common dermatological toxicities encountered during cancer treatment and offers measures for their prevention and management, particularly in the Australian/New Zealand context where skincare requirements may differ to other regions due to higher cumulative sun damage caused by high ambient ultraviolet (UV) light exposure. Given the frequency of these dermatological toxicities, a proactive phase is envisaged where patients can actively try to prevent skin toxicities.

Grade IV Radiation Skin Injury on the Neck of a Patient with Tonsillar Carcinoma: A Case Report

ABSTRACT

Radiation therapy is often accompanied by skin toxicity in the irradiated area and radiation-induced DNA damage to skin tissue cells in the surrounding pigmented area. This case report describes a patient with radiation-induced skin injury who received wound treatment and psychological intervention with satisfactory results. A 60-year-old woman was admitted to the authors' hospital on January 18, 2021, with radiation-induced skin injury caused by carbon ion radiotherapy for tonsillar carcinoma. The patient underwent wound repair combined with psychological intervention (30 minutes per dressing change). Over a period of 1 month, the wound area was reduced from 11 × 12 cm2 to 1 × 1 cm2, and wound symptoms (exudate, blood odor, wound infection, wound edge dehydration and curling, periwound skin peeling, dryness, and hyperkeratosis) improved. The patient's anxiety factor scores decreased from 18 to 1, and her depression factor scores decreased from 16 to 3. When the patient was discharged from the hospital after 1 month of treatment, she had a satisfactory self-image and normal social activities.

Emerging role of mesenchymal stem cell-derived exosome microRNA in radiation injury

PURPOSE

Radiation injury (RI) is a common occurrence in malignant tumors patients receiving radiation therapy. While killing tumor cells, normal tissue surrounding the target area is inevitably irradiated at a certain dose, which can cause varying results of radiation injury. Currently, there are limited clinical treatments available for radiation injuries. In recent years, the negative effects of stem cell therapy have been reported more clearly and non-cellular therapies such as exosomes have become a focus of attention for researchers. As a type of vesicle-like substances secreted by mesenchymal stem cells (MSC), MSC derived exosomes (MSC-exo) carry DNA, mRNA, microRNA (miRNAs), specific proteins, lipids, and other active substances involved in intercellular information exchange. miRNAs released by MSC-exo are capable of alleviating and repairing damaged tissues through anti-apoptosis, modulating immune response, regulating inflammatory response and promoting angiogenesis, which indicates that MSC-exo miRNAs have great potential for application in the prevention and treatment of radiation injury. Therefore, it is necessary to explore the underlying therapeutic mechanisms of MSC-exo miRNAs in this process, which may shed new lights on the treatment of radiation injury.

CONCLUSIONS

Increasing evidence confirms that MSC-exo has shown encouraging applications in tissue repair due to the anti-apoptotic, immunoreactive, and pro-angiogenesis effects of the miRNAs it carries as intercellular communication carriers. However, miRNA-based therapeutics are still in their infancy and many practical issues remain to be addressed for clinical applications.

Magnetic resonance imaging findings of radiation-induced breast angiosarcoma: A case report

BACKGROUND

Breast conservation surgery (BCS) with adjuvant radiotherapy has become a gold standard in the treatment of early-stage breast cancer, significantly reducing the risk of tumor recurrence. However, this treatment is associated with adverse effects, including the rare but aggressive radiation-induced angiosarcoma (RIAS). Despite its rarity and nonspecific initial presentation, RIAS presents a challenging diagnosis, emphasizing the importance of imaging techniques for early detection and accurate diagnosis.

CASE SUMMARY

We present a case of a 48-year-old post-menopausal woman who developed skin ecchymosis on the right breast seven years after receiving BCS and adjuvant radiotherapy for breast cancer. Initial mammography and ultrasound were inconclusive, showing post-treatment changes but failing to identify the underlying angiosarcoma. Contrast-enhanced breast magnetic resonance imaging (MRI) revealed diffuse skin thickening and nodularity with distinctive enhancement kinetics, leading to the diagnosis of RIAS. This case highlights the crucial role of MRI in diagnosing and determining the extent of RIAS, facilitating timely and appropriate surgical intervention.

CONCLUSION

Breast MRI is crucial for detecting RIAS, especially when mammography and ultrasound are inconclusive.

Skin dose-volume predictors of moderate-severe late side effects after whole breast radiotherapy

BACKGROUND

Toxicity after whole breast Radiotherapy is a relevant issue, impacting the quality-of-life of a not negligible number of patients. We aimed to develop a Normal Tissue Complication Probability (NTCP) model predicting late toxicities by combining dosimetric parameters of the breast dermis and clinical factors.

METHODS

The skin structure was defined as the outer CT body contour's 5 mm inner isotropic expansion. It was retrospectively segmented on a large mono-institutional cohort of early-stage breast cancer patients enrolled between 2009 and 2017 (n = 1066). Patients were treated with tangential-field RT, delivering 40 Gy in 15 fractions to the whole breast. Toxicity was reported during Follow-Up (FU) using SOMA/LENT scoring. The study endpoint was moderate-severe late side effects consisting of Fibrosis-Atrophy-Telangiectasia-Pain (FATP G ≥ 2) developed within 42 months after RT completion. A machine learning pipeline was designed with a logistic model combining clinical factors and absolute skin DVH (cc) parameters as output.

RESULTS

The FATP G2 + rate was 3.8 %, with 40/1066 patients experiencing side effects. After the preprocessing of variables, a cross-validation was applied to define the best-performing model. We selected a 4-variable model with Post-Surgery Cosmetic alterations (Odds Ratio, OR = 7.3), Aromatase Inhibitors (as a protective factor with OR = 0.45), V20 Gy (50 % of the prescribed dose, OR = 1.02), and V42 Gy (105 %, OR = 1.09). Factors were also converted into an adjusted V20Gy.

CONCLUSIONS

The association between late reactions and skin DVH when delivering 40 Gy/15 fr was quantified, suggesting an independent role of V20 and V42. Few clinical factors heavily modulate the risk.

Understanding therapeutic radiographers' confidence in assessing, managing & teaching radiation induced skin reactions (RISR): A national survey in the UK

INTRODUCTION

The standard toxicity tools adopted for assessing Radiation Induced Skin Reactions (RISR) do not currently reflect how skin changes occur across all skin tones. A one size fits all approach is adopted currently for RISR assessment. The aim of this study was to understand what evidence-based practice and RISR tools are being used across the therapeutic radiography workforce and the levels of confidence in using these tools.

METHODS

A survey using Likert scales to assess confidence in RISR assessment and management was made available to 77 departments in the UK between August-November 2021. Descriptive statistics were used to understand respondents' confidence in assessing, managing, and teaching RISR between white, brown, and black skin tones; Fisher's exact test was used to assess the significance of differences between groups.

RESULTS

Complete responses were received from 406 therapeutic radiographers. Radiation Therapy Oncology Group (RTOG) was the most used RISR assessment tool (58% of respondents n = 237). Most respondents (74.2% n = 303) reported use of locally produced patient information on skin care, rather than the Society and College of Radiographers evidence-based patient leaflets. Confidence in assessing and managing RISR in white skin was higher than that in brown and black skin. Similarly, confidence was higher in teaching of appropriate RISR assessment and management in white skin tones when compared to brown and black skin.

CONCLUSION

White skin tones appear to be more confidently assessed and managed for RISR along with taught appropriate assessment and management, than brown and black skin tones in the sample of the workforce that responded.

IMPLICATIONS FOR PRACTICE

A greater understanding of the reasons for these differences is required but this study aims to instigate change and positive growth within this area.

Comparison of Three Antagonists of Hedgehog Pathway to Promote Skeletal Muscle Regeneration after High Dose Irradiation

The current geopolitical context has brought the radiological nuclear risk to the forefront of concerns. High-dose localized radiation exposure leads to the development of a musculocutaneous radiation syndrome affecting the skin and subcutaneous muscles. Despite the implementation of a gold standard treatment based on an invasive surgical procedure coupled with autologous cell therapy, a muscular defect frequently persists. Targeting the modulation of the Hedgehog (Hh) signaling pathway appears to be a promising therapeutic approach. Activation of this pathway enhances cell survival and promotes proliferation after irradiation, while inhibition by Cyclopamine facilitates differentiation. In this study, we compared the effects of three antagonists of Hh, Cyclopamine (CA), Vismodegib (VDG) and Sonidegib (SDG) on differentiation. A stable cell line of murine myoblasts, C2C12, was exposed to X-ray radiation (5 Gy) and treated with CA, VDG or SDG. Analysis of proliferation, survival (apoptosis), morphology, myogenesis genes expression and proteins production were performed. According to the results, VDG does not have a significant impact on C2C12 cells. SDG increases the expression/production of differentiation markers to a similar extent as CA, while morphologically, SDG proves to be more effective than CA. To conclude, SDG can be used in the same way as CA but already has a marketing authorization with an indication against basal cell cancers, facilitating their use in vivo. This proof of concept demonstrates that SDG represents a promising alternative to CA to promotes differentiation of murine myoblasts. Future studies on isolated and cultured satellite cells and in vivo will test this proof of concept.

Quantifying radiation-induced breast fibrosis by shear-wave elastography in patients with breast cancer: A 12-months-follow-up data of a prospective study

Purpose

To assess radiation-induced fibrosis (RIF) using shear-wave elastography (SWE) in patients with breast cancer who received radiotherapy (RT) after breast conserving surgery.

Methods

Forty-one patients were enrolled in a prospective study before RT. SWE and B-mode ultrasonography were performed to measure elasticity. For quantitative measurement, the maximum elasticity value was measured in the tumor bed and non-tumor bed of the treated breast, and contralateral breast before RT and at 3, and 12 months after RT. and RIF was recorded using the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0.

Results

The mean ± standard deviation elasticity values for the tumor bed, non-tumor bed, and contralateral breast were 71.2 ± 74.9 kPa, 19.4 ± 9.8 kPa and 20.3 ± 10.0 kPa before RT; 28.7 ± 26.3 kPa, 15.1 ± 7.0 kPa, and 14.7 ± 6.3 kPa at 12 months after RT, respectively. The elasticity values for all three measurement areas before and 12 months after RT were significantly different (p < 0.001 for tumor bed, p = 0.002 for non-tumor bed, p = 0.001 for contralateral breast). At 12 months follow-up, the distribution of grades of RIF evaluated by CTCAE grade was grade 0 in 43.9 %, grade 1 in 48.8 %, and grade 2 in 7.3 %.

Conclusion

We demonstrated that SWE enables the evaluation of tissue stiffness to provide quantified information for the RIF of breast cancer. Further studies with long-term follow-up should provide more quantitative data.

Health Effects of Ionizing Radiation on the Human Body

Radioactivity is a process in which the nuclei of unstable atoms spontaneously decay, producing other nuclei and releasing energy in the form of ionizing radiation in the form of alpha (α) and beta (β) particles as well as the emission of gamma (γ) electromagnetic waves. People may be exposed to radiation in various forms, as casualties of nuclear accidents, workers in power plants, or while working and using different radiation sources in medicine and health care. Acute radiation syndrome (ARS) occurs in subjects exposed to a very high dose of radiation in a very short period of time. Each form of radiation has a unique pathophysiological effect. Unfortunately, higher organisms-human beings-in the course of evolution have not acquired receptors for the direct "capture" of radiation energy, which is transferred at the level of DNA, cells, tissues, and organs. Radiation in biological systems depends on the amount of absorbed energy and its spatial distribution, particularly depending on the linear energy transfer (LET). Photon radiation with low LET leads to homogeneous energy deposition in the entire tissue volume. On the other hand, radiation with a high LET produces a fast Bragg peak, which generates a low input dose, whereby the penetration depth into the tissue increases with the radiation energy. The consequences are mutations, apoptosis, the development of cancer, and cell death. The most sensitive cells are those that divide intensively-bone marrow cells, digestive tract cells, reproductive cells, and skin cells. The health care system and the public should raise awareness of the consequences of ionizing radiation. Therefore, our aim is to identify the consequences of ARS taking into account radiation damage to the respiratory system, nervous system, hematopoietic system, gastrointestinal tract, and skin.

Comparison of the efficacy among different interventions for radiodermatitis: A Bayesian network meta‑analysis of randomized controlled trials

BACKGROUND

Radiation dermatitis (RD) is a prevalent and difficult-to-manage consequence of radiation therapy (RT). A variety of interventions have been proven effective in preventing and treating RD. However, the optimal approach remains unclear. This network meta-analysis (NMA) conducted a comparison and ranking of the effectiveness and patient-reported outcomes (PROs) of the interventions currently utilized in RD.

METHODS

PubMed, Web of Science, Embase, and Cochrane Library were searched to identify pertinent randomized controlled trials (RCTs) focused on the prevention and treatment of RD. The primary outcome measures included the incidence of grade≥2 RD (i.e., percentage of moist desquamation) and RD score. The secondary outcome measures encompassed patients' subjective assessment scores of pains, itching and burning sensations.

RESULTS

Our meta-analysis encompassed 42 studies and 4884 participants. Regarding the primary outcomes, photobiomodulation treatment (PBMT) ranked first in surface under curve cumulative ranking area (SUCRA:0.92) for reducing the incidence of grade≥2 RD. It demonstrated a significant difference when compared to Trolamine (OR 0.18,95%CrI 0.09-0.33) and Xonrid® (OR 0.28,95%CrI 0.12-0.66). Mepitelfilm (SUCRA: 0.98) achieved the highest rank in reducing the RD score, demonstrating superiority over StrataXRT® (MD -0.89, 95% CrI -1.49, -0.29). Henna (SUCRA: 0.89) demonstrated the highest effectiveness in providing pain relief, with a significant difference compared to Hydrofilm (MD -0.44, 95% CrI -0.84, -0.04) and Mepitelfilm (MD -0.55, 95% CrI -0.91, -0.19). Hydrofilm (SUCRA: 0.84) exhibited the fewest itching sensations, demonstrating superiority over Mepitelfilm (MD -0.50, 95% CrI -0.84, -0.17). No statistically significant difference was observed among various interventions in the assessment of burning sensations.

CONCLUSION

PBMT and Mepitelfilm demonstrated better efficacy in reducing the incidence of grade≥2 RD and RD score, respectively. In terms of PROs, Henna and Hydrofilm had fewer complaints in pain and itching sensations, respectively. However, studies with larger sample size on different interventions are warranted in the future.

TRIAL REGISTRATION

PROSPERO registration number CRD42023428598.

The need for a holistic guide to prevent and manage radiation dermatitis in patients' with breast cancer: a case report

Background

Radiation therapy (RT) is often indicated in the treatment of breast cancer following breast conserving surgery or mastectomy, yet carries a 95% risk of radiation dermatitis (RD) of varying severity within 1 to 4 weeks of treatment. The burdens of RT include skin breakdown, pain, psychological distress, and functional challenges. Given limited patient education regarding the prevention and management of RD, a Clinician Guide and Evidence-based Skin Care Plan were developed to offer a holistic, patient-centered approach to care, with optimal RD prevention and management strategies to enhance patients' quality of life and survival.

Case Description

M.R. (a pseudonym) was a 64-year-old Caucasian woman, diagnosed with invasive adenocarcinoma of the left breast, underwent a lumpectomy with a positive sentinel node biopsy. Within 4 weeks of surgery, she received RT, 5 days a week for 6 weeks. Within 1 week, the skin of her breast and axilla was red and hyperpigmented with skin damage progressing to dryness, itching and flaking. At this point, she asked the Radiology team for a skin care protocol to prevent or reduce RD, but limited information was provided. Ultimately, her skin cracked, blistered and crusted, with the development of a skin infection. She expressed the significant impact on her physical, emotional and functional well-being, and lamented about the shortfalls in her care, specifically the limited availability of information to prevent and reduce RD.

Conclusions

In order to prevent and minimize RD and to promote health, this case study highlights the need for an all-encompassing, patient-centered approach to care, which may be achievable by implementation of a Clinician Guide and an Evidence-based Skin Care Plan. Highlighted in the Clinician Guide are the importance of developing a trustworthy patient-clinician relationship, emotional support, social support, education, weekly physical assessments, assessment of overall adjustment to a cancer diagnosis and treatment, promotion of patient engagement and self-care, reinforcement of healthy lifestyles, and patient adherence to the Evidence-based Skin Care Plan during RT. These strategies are expected to decrease the physical, mental, and functional difficulties associated with RT, avoid treatment delays or discontinuation, and increase the likelihood of disease-free survival and quality of life.

Immunomodulatory Effects of Histone Variant H2A.J in Ionizing Radiation Dermatitis

PURPOSE

Histone variant H2A.J is associated with premature senescence after ionizing radiation (IR) and modulates senescence-associated secretory phenotype (SASP). Using constitutive H2A.J knock-out mice, the role of H2A.J was investigated in radiation dermatitis.

METHODS AND MATERIALS

H2A.J wild-type (WT) and knock-out (KO) mice were exposed to moderate or high IR doses (≤20 Gy, skinfold IR). Radiation-induced skin reactions were investigated up to 2 weeks post-IR at macroscopic and microscopic levels. H2A.J and other senescence markers, as well as DNA damage and proliferation markers, were studied by immunohistochemistry, immunofluorescence, and electron microscopy. After high-dose IR, protein-coding transcriptomes were analyzed by RNA sequencing, immune cell infiltration by flow cytometry, and gene expression by reverse transcription polymerase chain reaction in (non-) irradiated WT versus KO skin.

RESULTS

In WT skin, epidermal keratinocytes showed time- and dose-dependent H2A.J accumulation after IR exposure. Unexpectedly, stronger inflammatory reactions with increased epidermal thickness and progressive hair follicle loss were observed in irradiated KO versus WT skin. Clearly more radiation-induced senescence was observed in keratinocyte populations of KO skin after moderate and high doses, with hair follicle stem cells being particularly badly damaged, leading to follicle atrophy. After high-dose IR, transcriptomic analysis revealed enhanced senescence-associated signatures in irradiated KO skin, with intensified release of SASP factors. Flow cytometric analysis indicated increased immune cell infiltration in both WT and KO skin; however, specific chemokine-mediated signaling in irradiated KO skin led to more neutrophil recruitment, thereby aggravating radiation toxicities. Increased skin damage in irradiated KO skin led to hyperproliferation, abnormal differentiation, and cornification of keratinocytes, accompanied by increased upregulation of transcription-factor JunB.

CONCLUSIONS

Lack of radiation-induced H2A.J expression in keratinocytes is associated with increased senescence induction, modulation of SASP expression, and exacerbated inflammatory skin reactions. Hence, epigenetic H2A.J-mediated gene expression in response to IR regulates keratinocyte immune functions and plays an essential role in balancing the inflammatory response during radiation dermatitis.

Effect of bisphosphonates and statins on the in vitro radiosensitivity of breast cancer cell lines

BACKGROUND

Early-stage breast cancer is usually treated with breast-conserving surgery followed by adjuvant radiation therapy. Acute skin toxicity is a common radiation-induced side effect experienced by many patients. Recently, a combination of bisphosphonates (zoledronic acid) and statins (pravastatin), or ZOPRA, was shown to radio-protect normal tissues by enhancing DNA double-strand breaks (DSB) repair mechanism. However, there are no studies assessing the effect of ZOPRA on cancerous cells. The purpose of this study is to characterize the in vitro effect of the zoledronic acid (ZO), pravastatin (PRA), and ZOPRA treatment on the molecular and cellular radiosensitivity of breast cancer cell lines.

MATERIALS

Two breast cancer cell lines, MDA MB 231 and MCF-7, were tested. Cells were treated with different concentrations of pravastatin (PRA), zoledronate (ZO), as well as their ZOPRA combination, before irradiation. Anti-γH2AX and anti-pATM immunofluorescence were performed to study DNA DSB repair kinetics. MTT assay was performed to assess cell proliferation and viability, and flow cytometry was performed to analyze the effect of the drugs on the cell cycle distribution. The clonogenic assay was used to assess cell survival.

RESULTS

ZO, PRA, and ZOPRA treatments were shown to increase the residual number of γH2AX foci for both cell lines. ZOPRA treatment was also shown to reduce the activity of the ATM kinase in MCF-7. ZOPRA induced a significant decrease in cell survival for both cell lines.

CONCLUSIONS

Our findings show that pretreatment with ZOPRA can decrease the radioresistance of breast cancer cells at the molecular and cellular levels. The fact that ZOPRA was previously shown to radioprotect normal tissues, makes it a good candidate to become a therapeutic window-widening drug.

microRNA blood signature for localized radiation injury

A radiological accident, whether from industrial, medical, or malicious origin, may result in localized exposure to high doses of ionizing radiations, leading to the development of local radiation injury (LRI), that may evolve toward deep ulceration and necrosis of the skin and underlying tissues. Early diagnosis is therefore crucial to facilitate identification and management of LRI victims. Circulating microRNAs (miRNA) have been studied as potential diagnostic biomarkers of several diseases including hematological defects following whole-body irradiation (WBI). This study aims to identify a blood miRNA signature associated with LRI in a preclinical C57BL/6J mouse model of hindlimb irradiation using different 10-MV X-ray doses that lead to injuries of different severities. To this end, we first performed broad-spectrum plasma miRNA profiling, followed by a targeted validation step, on two independent animal cohorts. Using a multivariate sparse partial least square discriminant analysis, we identified a panel of eight circulating miRNAs able to segregate mice according to LRI severity. Interestingly, these miRNAs were previously associated with WBI (miR-150-5p, miR-342-3p, miR-146a-5p), inflammation (miR-18a-5p, miR-148b-3p, miR-532-5p) and skin diseases (miR-139-5p, miR-195-5p). Our results suggest the use of circulating miRNAs as suitable molecular biomarkers for LRI prognosis and diagnosis.

Exploring the mechanisms behind autologous lipotransfer for radiation-induced fibrosis: A systematic review

AIM

Radiation-induced fibrosis is a recognised consequence of radiotherapy, especially after multiple and prolonged dosing regimens. There is no definitive treatment for late-stage radiation-induced fibrosis, although the use of autologous fat transfer has shown promise. However, the exact mechanisms by which this improves radiation-induced fibrosis remain poorly understood. We aim to explore existing literature on the effects of autologous fat transfer on both in-vitro and in-vivo radiation-induced fibrosis models, and to collate potential mechanisms of action.

METHOD

PubMed, Cochrane reviews and Scopus electronic databases from inception to May 2023 were searched. Our search strategy combined both free-text terms with Boolean operators, derived from synonyms of adipose tissue and radiation-induced fibrosis.

RESULTS

The search strategy produced 2909 articles. Of these, 90 underwent full-text review for eligibility, yielding 31 for final analysis. Nine conducted in-vitro experiments utilising a co-culture model, whilst 25 conducted in-vivo experiments. Interventions under autologous fat transfer included adipose-derived stem cells, stromal vascular function, whole fat and microfat. Notable findings include downregulation of fibroblast proliferation, collagen deposition, epithelial cell apoptosis, and proinflammatory processes. Autologous fat transfer suppressed hypoxia and pro-inflammatory interferon-γ signalling pathways, and tissue treated with adipose-derived stem cells stained strongly for anti-inflammatory M2 macrophages. Although largely proangiogenic initially, studies show varying effects on vascularisation. There is early evidence that adipose-derived stem cell subgroups may have different functional properties.

CONCLUSION

Autologous fat transfer functions through pro-angiogenic, anti-fibrotic, immunomodulatory, and extracellular matrix remodelling properties. By characterising these mechanisms, relevant drug targets can be identified and used to further improve clinical outcomes in radiation-induced fibrosis. Further research should focus on adipose-derived stem cell sub-populations and augmentation techniques such as cell-assisted lipotransfer.

Temporary Knockdown of p53 During Focal Limb Irradiation Increases the Development of Sarcomas

Approximately half of patients with cancer receive radiotherapy and, as cancer survivorship increases, the low rate of radiation-associated sarcomas is rising. Pharmacologic inhibition of p53 has been proposed as an approach to ameliorate acute injury of normal tissues from genotoxic therapies, but how this might impact the risk of therapy-induced cancer and normal tissue injuries remains unclear. We utilized mice that express a doxycycline (dox)-inducible p53 short hairpin RNA to reduce Trp53 expression temporarily during irradiation. Mice were placed on a dox diet 10 days prior to receiving 30 or 40 Gy hind limb irradiation in a single fraction and then returned to normal chow. Mice were examined weekly for sarcoma development and scored for radiation-induced normal tissue injuries. Radiation-induced sarcomas were subjected to RNA sequencing. Following single high-dose irradiation, 21% of animals with temporary p53 knockdown during irradiation developed a sarcoma in the radiation field compared with 2% of control animals. Following high-dose irradiation, p53 knockdown preserves muscle stem cells, and increases sarcoma development. Mice with severe acute radiation-induced injuries exhibit an increased risk of developing late persistent wounds, which were associated with sarcomagenesis. RNA sequencing revealed radiation-induced sarcomas upregulate genes related to translation, epithelial-mesenchymal transition (EMT), inflammation, and the cell cycle. Comparison of the transcriptomes of human and mouse sarcomas that arose in irradiated tissues revealed regulation of common gene programs, including elevated EMT pathway gene expression. These results suggest that blocking p53 during radiotherapy could minimize acute toxicity while exacerbating late effects including second cancers.

SIGNIFICANCE

Strategies to prevent or mitigate acute radiation toxicities include pharmacologic inhibition of p53 and other cell death pathways. Our data show that temporarily reducing p53 during irradiation increases late effects including sarcomagenesis.

Keratin 17 Impacts Global Gene Expression and Controls G2/M Cell Cycle Transition in Ionizing Radiation-Induced Skin Damage

Keratin 17 (K17) is a cytoskeletal protein that is part of the intermediate filaments in epidermal keratinocytes. In K17-/- mice, ionizing radiation induced more severe hair follicle damage, whereas the epidermal inflammatory response was attenuated compared with that in wild-type mice. Both p53 and K17 have a major impact on global gene expression because over 70% of the differentially expressed genes in the skin of wild-type mice showed no expression change in p53-/- or K17-/- skin after ionizing radiation. K17 does not interfere with the dynamics of p53 activation; rather, global p53 binding in the genome is altered in K17-/- mice. The absence of K17 leads to aberrant cell cycle progression and mitotic catastrophe in epidermal keratinocytes, which is due to nuclear retention, thus reducing the degradation of B-Myb, a key regulator of the G2/M cell cycle transition. These results expand our understanding of the role of K17 in regulating global gene expression and ionizing radiation-induced skin damage.

Structural racism in radiation induced skin reaction toxicity scoring

Racially motivated biases are often implicit and can go unnoticed, especially if your normal is white and adjustments are required to cater for 'others.' Current consent forms and grading tools within radiotherapy are not inclusive of all skin tones. This commentary highlights gaps in care within radiation induced skin reactions (RISR) assessment for people of colour. Healthcare professionals and patients are directed to look for visual cues such as redness for RISR, but this is not always visible on people with pigmented skin. Their skin may go darker than their normal or changes across the colour spectrum. The lack of understanding of these fundamental differences are leading to people of colour being oppressed through structural racism and racialised myths. Using inclusive terminology will allow for moving away from the current view of healthcare that white skin is the norm. People of colour deserve more than are currently offered in RISR toxicity assessment.

An Experimental Model of Proton-Beam-Induced Radiation Dermatitis In Vivo

Radiation dermatitis (RD) is one of the most common side effects of radiation therapy. However, to date, there is a lack of both specific treatments for RD and validated experimental animal models with the use of various sources of ionizing radiation (IR) applied in clinical practice. The aim of this study was to develop and validate a model of acute RD induced using proton radiation in mice. Acute RD (Grade 2-4) was obtained with doses of 30, 40, and 50 Gy, either with or without depilation. The developed model of RD was characterized by typical histological changes in the skin after irradiation. Moreover, the depilation contributed to a skin histology alteration of the irradiated mice. The assessment of animal vital signs indicated that there was no effect of proton irradiation on the well-being or general condition of the animals. This model can be used to develop effective therapeutic agents and study the pathogenesis of radiation-induced skin toxicity, including that caused by proton irradiation.

A blinded-endpoint, randomized controlled trial of Sanyrene with natural active ingredient for prophylaxis of radiation dermatitis in patients receiving radiotherapy

BACKGROUND

Randomized controlled study was conducted to evaluate the efficacy of Sanyrene® vs. control intervention (DaBao®, a complex of hyaluronic acid and Vitamin E) for acute radiation dermatitis in patients receiving radiotherapy.

METHODS

Patients with breast cancer or head and neck cancer undergoing radiotherapy (≥ 50 Gy) were eligible. Participants were randomly assigned to either Sanyrene arm or control intervention arm in a ratio of 1:1. The primary endpoint was incidence rate of ≥ grade 2 radiation induced dermatitis. (Trial Registration: ChiCTR2100050910, registration date: 9/7/2021) RESULTS: A total of 102 eligible patients were randomly assigned into the study. The rate of ≥ grade 2 radiation dermatitis was 22% in Sanyrene group, as compared with 67.3% in the control intervention group (P<0.001). The incidence of grade 3 radiation dermatitis was 20.4% and 8.0% in control intervention group and Sanyrene group, respectively (P = 0.076). Patients in Sanyrene group had a longer median time to reach ≥ grade 2 radiation dermatitis compared to these in control intervention group, with hazard ratio of 0.231 (95%CI:0.116-0.458, p < 0.001). Mean score of SD-16 were much higher in control intervention group than Sanyrene group at end of radiotherapy (25 vs.8.3), 2 weeks after radiotherapy (22.9 vs. 0.5) and 4 weeks after radiotherapy (4.2 vs.0), with significantly statistical difference between two groups.

CONCLUSIONS

This trial suggests that Sanyrene is effective on preventing serious radiation dermatitis and improving skin related quality of life in patients with breast cancer or head and neck cancer receiving radiotherapy.

[Metformin alleviates pathologic pain in mice with radiation dermatitis by inhibiting p38MAPK/NF-κB signaling pathway]

OBJECTIVE

To observe the therapeutic effect of metformin on pathological pain in mice with radiation dermatitis and explore the underlying mechanism.

METHODS

Thirty-two male adult ICR mice were randomized into normal control group, radiation dermatitis model group, metformin treatment (200 mg/kg) group and gabapentin (100 mg/kg) group (n=8).In the latter two groups, metformin treatment was administered after modeling via intraperitoneal injection and gabapentin by gavage on a daily basis for 16 days; the mice in the control group and model group received intraperitoneal injection of normal saline.After the last administration, radiation dermatitis was graded in each group.Mechanical withdraw threshold (MWT) and thermal withdrawal latency (TWL) of the mice were tested one day before and at 1, 4, 8, 12 and 16 days after modeling.Western blotting was used to measure the protein expression levels of p38MAPK, p-p38MAPK, NF-κB p65 and p-NF-κB p65 in the L4-L6 spinal cord, and the concentrations of IL-1β, IL-6 and TNF-α in the spinal cord tissue were determined with ELISA.

RESULTS

Compared with those in the control group, the mice in the other 3 groups showed obvious symptoms of radiation dermatitis after modeling (P<0.05), which were significantly alleviated by treatment with metformin (P<0.05).The mice in the model group exhibited significant decreases in MWT and TWL (P<0.05), which were improved by treatment with metformin and gabapentin (P<0.05).Compared with those in the model group, the levels of p-p38MAPK, p-NF-κB p65, IL-1β, IL-6 and TNF-α in the spinal cord were significantly decreased in the mice after metformin treatment (P<0.05).

CONCLUSION

Metformin can significantly ameliorate pathological pain symptoms in mice with radiation dermatitis possibly by inhibiting the activation of p38MAPK/NF-κB signaling pathway.

Nano-Architecture of Persistent Focal DNA Damage Regions in the Minipig Epidermis Weeks after Acute γ-Irradiation

Exposure to high acute doses of ionizing radiation (IR) can induce cutaneous radiation syndrome. Weeks after such radiation insults, keratinocyte nuclei of the epidermis exhibit persisting genomic lesions that present as focal accumulations of DNA double-strand break (DSB) damage marker proteins. Knowledge about the nanostructure of these genomic lesions is scarce. Here, we compared the chromatin nano-architecture with respect to DNA damage response (DDR) factors in persistent genomic DNA damage regions and healthy chromatin in epidermis sections of two minipigs 28 days after lumbar irradiation with ~50 Gy γ-rays, using single-molecule localization microscopy (SMLM) combined with geometric and topological mathematical analyses. SMLM analysis of fluorochrome-stained paraffin sections revealed, within keratinocyte nuclei with perisitent DNA damage, the nano-arrangements of pATM, 53BP1 and Mre11 DDR proteins in γ-H2AX-positive focal chromatin areas (termed macro-foci). It was found that persistent macro-foci contained on average ~70% of 53BP1, ~23% of MRE11 and ~25% of pATM single molecule signals of a nucleus. MRE11 and pATM fluorescent tags were organized in focal nanoclusters peaking at about 40 nm diameter, while 53BP1 tags formed nanoclusters that made up super-foci of about 300 nm in size. Relative to undamaged nuclear chromatin, the enrichment of DDR protein signal tags in γ-H2AX macro-foci was on average 8.7-fold (±3) for 53BP1, 3.4-fold (±1.3) for MRE11 and 3.6-fold (±1.8) for pATM. The persistent macro-foci of minipig epidermis displayed a ~2-fold enrichment of DDR proteins, relative to DSB foci of lymphoblastoid control cells 30 min after 0.5 Gy X-ray exposure. A lasting accumulation of damage signaling and sensing molecules such as pATM and 53BP1, as well as the DSB end-processing protein MRE11 in the persistent macro-foci suggests the presence of diverse DNA damages which pose an insurmountable problem for DSB repair.

Tissue fibrosis induced by radiotherapy: current understanding of the molecular mechanisms, diagnosis and therapeutic advances

Cancer remains the leading cause of death around the world. In cancer treatment, over 50% of cancer patients receive radiotherapy alone or in multimodal combinations with other therapies. One of the adverse consequences after radiation exposure is the occurrence of radiation-induced tissue fibrosis (RIF), which is characterized by the abnormal activation of myofibroblasts and the excessive accumulation of extracellular matrix. This phenotype can manifest in multiple organs, such as lung, skin, liver and kidney. In-depth studies on the mechanisms of radiation-induced fibrosis have shown that a variety of extracellular signals such as immune cells and abnormal release of cytokines, and intracellular signals such as cGAS/STING, oxidative stress response, metabolic reprogramming and proteasome pathway activation are involved in the activation of myofibroblasts. Tissue fibrosis is extremely harmful to patients' health and requires early diagnosis. In addition to traditional serum markers, histologic and imaging tests, the diagnostic potential of nuclear medicine techniques is emerging. Anti-inflammatory and antioxidant therapies are the traditional treatments for radiation-induced fibrosis. Recently, some promising therapeutic strategies have emerged, such as stem cell therapy and targeted therapies. However, incomplete knowledge of the mechanisms hinders the treatment of this disease. Here, we also highlight the potential mechanistic, diagnostic and therapeutic directions of radiation-induced fibrosis.

Carbon-fiber alternative to the commercial gating surrogate for the Varian Truebeam™

BACKGROUND

In this study we present the Tracking Accessory 3 (TA3) as an alternative to the commercial gating block (GB) surrogate for the Varian Truebeam™ gating system (TGS). The TGS requires three visible reflectors to track the surrogate, presenting an opportunity for a surrogate to be made with less material and thus smaller dosimetric footprint than the commercial four reflector model.

MATERIALS AND METHODS

Relative dose and depth dose profiles below the TA3 and the GB were measured with radiosensitive film. Accuracy and reproducibility of the detected motion amplitude for three TA3s and one GB were determined using a respiratory phantom with surrogate to determine the camera's tracking volume. Clinical performance was evaluated prospectively in 10 breast cancer patients treated with deep inspiration breath hold monitored with TA3 and compared to previously published results. Non-parametric statistics were applied to test for significance.

RESULTS AND CONCLUSIONS

Surface doses were increased up to 94% and 187% for the TA3 and GB, respectively, compared to no surrogate. The surface area influenced by at least 25% increase in dose was 12 cm2 and 105 cm2 for the TA3 and GB, respectively. The water equivalent thickness of the surrogates was found to be 1 mm for the TA3 and 3 mm for GB. The difference in measured amplitude were <0.2 mm for TA3 compared to the GB. The TA3s and GB were detected at all extremes of the clinically relevant tracking volume of the TGS. Clinical performance showed no significant differences. The TA3 caused less surface dose increase compared to the commercial GB. In the tested range all surrogates measured motion amplitude within 0.2 mm of reference value, which is not a clinically relevant difference. The TA3 showed no significant differences in clinical performance to similarly positioned surrogates.

Risk of Radiation Dermatitis in Patients With Skin of Color Who Undergo Radiation to the Breast or Chest Wall With and Without Regional Nodal Irradiation

PURPOSE

Acute radiation dermatitis (ARD) is common after radiation therapy for breast cancer, with data indicating that ARD may disproportionately affect Black or African American (AA) patients. We evaluated the effect of skin of color (SOC) on physician-reported ARD in patients treated with radiation therapy.

METHODS AND MATERIALS

We identified patients treated with whole breast or chest wall ± regional nodal irradiation or high tangents using 50 Gy in 25 fractions from 2015 to 2018. Baseline skin pigmentation was assessed using the Fitzpatrick scale (I = light/pale white to VI = black/very dark brown) with SOC defined as Fitzpatrick scale IV to VI. We evaluated associations among SOC, physician-reported ARD, late hyperpigmentation, and use of oral and topical treatments for RD using multivariable models.

RESULTS

A total of 325 patients met eligibility, of which 40% had SOC (n = 129). On multivariable analysis, Black/AA race and chest wall irradiation had a lower odds of physician-reported grade 2 or 3 ARD (odds ratio [OR], 0.110; 95% confidence interval [CI], 0.030-0.397; P = .001; OR, 0.377; 95% CI, 0.161-0.883; P = .025), whereas skin bolus (OR, 8.029; 95% CI, 3.655-17.635; P = 0) and planning target volume D0.03cc (OR, 1.001; 95% CI, 1.000-1.001; P = .028) were associated with increased odds. On multivariable analysis, SOC (OR, 3.658; 95% CI, 1.236-10.830; P = .019) and skin bolus (OR, 26.786; 95% CI, 4.235-169.432; P = 0) were associated with increased odds of physician-reported late grade 2 or 3 hyperpigmentation. There was less frequent use of topical steroids to treat ARD and more frequent use of oral analgesics in SOC versus non-SOC patients (43% vs 63%, P < .001; 50% vs 38%, P = .05, respectively).

CONCLUSIONS

Black/AA patients exhibited lower odds of physician-reported ARD. However, we found higher odds of late hyperpigmentation in SOC patients, independent of self-reported race. These findings suggest that ARD may be underdiagnosed in SOC when using the physician-rated scale despite this late evidence of radiation-induced skin toxicity.

Dermoscopy of acute radiation-induced dermatitis in patients with head and neck cancers treated with radiotherapy

Head and neck cancer (HNC) was the seventh most common cancer in the world in 2018. Treatment of a patient may include surgery, radiotherapy (RT), chemotherapy, targeted therapy, immunotherapy, or a combination of these methods. Ionizing radiation used during RT covers relatively large volumes of healthy tissue surrounding the tumor. The acute form of radiation-induced dermatitis (ARD) are skin lesions that appear usually within 90 days of the start of RT. This is a prospective study which compares 2244 dermoscopy images and 374 clinical photographs of irradiated skin and healthy skin of 26 patients at on average 15 time points. Dermoscopy pictures were evaluated independently by 2 blinded physicians. Vessels in reticular distribution, white, yellow or brown scale in a patchy distribution, perifollicular pigmentation and follicular plugs arranged in rosettes were most often observed. For these dermoscopic features, agreement with macroscopic features was observed. Two independent predictors of severe acute toxicity were identified: gender and concurrent chemotherapy. Knowledge of dermoscopic features could help in the early assessment of acute toxicity and the immediate implementation of appropriate therapeutic strategies. This may increase the tolerance of RT in these groups of patients.

Antioxidative stress protein SRXN1 can be used as a radiotherapy prognostic marker for prostate cancer

PURPOSE

To explore the mechanisms of radiotherapy resistance and search for prognostic biomarkers for prostate cancer.

METHODS

The GSE192817 and TCGA PRAD datasets were selected and downloaded from the GEO and UCSC Xena databases. Differential expression and functional annotation analyses were applied to 52 tumour cell samples from GSE192817. Then, the ssGSEA or GSVA algorithms were applied to quantitatively score the biological functional activity of samples in the GSE192817 and TCGA PRAD datasets, combined with specific gene sets collected from the Molecular Signatures Database (MSigDB). Subsequently, the Wilcoxon rank-sum test was used to compare the differences in ssGSEA or GSVA scores among cell types or PRAD patients. Moreover, radiotherapy resistance-associated gene screening was performed on DU145 and PC3 cells (prostate cancer cells), and survival analysis was used to evaluate the efficacy of these genes for predicting the prognosis of PRAD patients.

RESULTS

A total of 114 genes that were differentially expressed in more than two different cancer cell types and associated with either sham surgery or radiotherapy treatment (X-ray or photon irradiation) were detected in cancer cells from GSE192817. Comparison of DNA damage-related ssGSEA scores between sham surgery and radiotherapy treatment in prostate cancer cells (DU145 and PC3) showed that photon irradiation was potentially more effective than X-ray treatment. In the TCGA PRAD dataset, patients treated with radiotherapy had much higher "GOBP_CELLULAR_RESPONSE_TO_DNA_DAMAGE_STIMULUS", "GOBP_G2_DNA_DAMAGE_CHECKPOINT" and "GOBP_INTRA_S_DNA_DAMAGE_CHECKPOINT" GSVA scores, and the Wilcoxon rank-sum test p values were 0.0005, 0.0062 and 0.0800, respectively. Furthermore, SRXN1 was upregulated in DU145 cells (resistant to X-ray irradiation compared to PC3 cells) after radiotherapy treatment, and low SRXN1 expression in patients was beneficial to radiotherapy outcomes. The log-rank test p value for PFS was 0.0072.

CONCLUSIONS

Radiotherapy can damage DNA and induce oxidative stress to kill tumour cells. In this study, we found that SRXN1, as an antioxidative stress gene, plays an important role in radiotherapy for prostate cancer treatment, and this gene is also a potential biomarker for predicting the prognosis of patients treated with radiotherapy.

RISREAC Study: Assessment of Cutaneous Radiation Injury Through Clinical Documentation

OBJECTIVE

Radiation dermatitis (RD) occurs in 95% of patients receiving radiation therapy (RT) for cancer treatment, affecting 800 million patients annually. We aimed to demonstrate the feasibility of developing a historical RD cohort, Radiation Induced Skin Reactions (RISREAC) cohort.

METHODS

This retrospective study evaluated RD-related clinical documentation for 245 breast cancer patients who received RT at the University of Rochester Medical Center, to understand the RD progression, scoring, and management. All statistical analyses were performed at 0.05 level of significance.

RESULTS

Clinician-documented RD severity was observed for 169 (69%) patients with a mean severity of 1.57 [1.46, 1.68]. The mean descriptor-based severity score of 2.31 [2.18, 2.45] moderately correlated (r = 0.532, P < 0.0001) with documented RD grade. Most patients (91.8%) received skin care treatment during RT, with 66.7% receiving more than 2 modalities.

CONCLUSIONS

The RISREAC cohort is the first retrospective cohort established from clinical documentation of radiation-induced skin changes for the study of RD and cutaneous radiation injury (CRI). RD symptom descriptors were more reliably documented and suitable for all skin types compared to Radiation Therapy Oncology Group (RTOG) or Common Toxicity Criteria for Adverse Events (CTCAE) grades. A new descriptor-based scoring tool would be useful for RD and CRI.

The Role of Radiation Therapy in Adult and Pediatric Keloid Management: A National Survey of Radiation Oncologists

INTRODUCTION

Radiation therapy is a promising modality for treating keloids after surgical excision. However, it is currently not standard practice among physicians because of concern surrounding the risk of radiation-induced secondary cancers, especially among pediatric patients. There is minimal research assessing the complications for radiation therapy in keloid management.

AIM

The goal of this study was to determine radiation oncologists' perspectives about the utility and appropriateness of radiation therapy for keloid management in both adult and pediatric patients. This study also aimed to characterize radiation modality, dose, fractionation, and secondary complications observed by providers.

METHODS

An electronic survey was delivered to 3102 members of the American Society for Radiation Oncology. The survey subjects were radiation oncologists who are currently practicing in the United States. Rates of responses were analyzed.

RESULTS

A total of 114 responses from practicing radiation oncologists were received. Of these, 113 providers (99.1%) supported radiation therapy for keloid management in adults, whereas only 54.9% supported radiation therapy for pediatric patients. Of 101 providers that treated adults in the past year, the majority used external beam: electrons (84.2%), applied 3 fraction regimens (54.4%), and delivered radiation within 24 hours postexcision (45.5%). In pediatric patients, only 42 providers reported treating at least 1 patient. The majority used electron beam radiation (76.2%), applied 3 faction regimens (65%), and delivered radiation on the same day of keloid excision (50.0%) The main concern when treating pediatric patients were risk of secondary malignancy (92.1%).

CONCLUSION

Although radiation therapy appears to be a widely accepted adjuvant treatment option for adults with keloids, the use of radiation therapy for pediatric patients is less widely accepted because of concerns regarding secondary malignancy. The findings suggest additional studies need to be carried out to assess the risk of those complications.

Personalized Medicine in Cancer Pain Management

BACKGROUND

Previous studies have documented pain as an important concern for quality of life (QoL) and one of the most challenging manifestations for cancer patients. Thus, cancer pain management (CPM) plays a key role in treating pain related to cancer. The aim of this systematic review was to investigate CPM, with an emphasis on personalized medicine, and introduce new pharmacogenomics-based procedures for detecting and treating cancer pain patients.

METHODS

This study systematically reviewed PubMed from 1990 to 2023 using keywords such as cancer, pain, and personalized medicine. A total of 597 publications were found, and after multiple filtering processes, 75 papers were included. In silico analyses were performed using the GeneCards, STRING-MODEL, miRTargetLink2, and PharmGKB databases.

RESULTS

The results reveal that recent reports have mainly focused on personalized medicine strategies for CPM, and pharmacogenomics-based data are rapidly being introduced. The literature review of the 75 highly relevant publications, combined with the bioinformatics results, identified a list of 57 evidence-based genes as the primary gene list for further personalized medicine approaches. The most frequently mentioned genes were CYP2D6, COMT, and OPRM1. Moreover, among the 127 variants identified through both the literature review and data mining in the PharmGKB database, 21 variants remain as potential candidates for whole-exome sequencing (WES) analysis. Interestingly, hsa-miR-34a-5p and hsa-miR-146a-5p were suggested as putative circulating biomarkers for cancer pain prognosis and diagnosis.

CONCLUSIONS

In conclusion, this study highlights personalized medicine as the most promising strategy in CPM, utilizing pharmacogenomics-based approaches to alleviate cancer pain.