Impact of concurrent medications on clinical outcomes of cancer patients treated with immune checkpoint inhibitors: analysis of Health Insurance Review and Assessment data.

PURPOSE: Medications regulating immune homeostasis and gut microbiota could affect the efficacy of immune checkpoint inhibitors (ICIs). This study aimed to investigate the impact of concurrent medications on the clinical outcomes of patients with cancer receiving ICI therapy in South Korea. METHODS: We identified patients newly treated with ICI for non-small cell lung cancer (NSCLC), urothelial carcinoma (UC), and malignant melanoma (MM) between August 2017 and June 2020 from a nationwide database in Korea. The effect of concurrent antibiotics (ATBs), corticosteroids (CSs), proton-pump inhibitors (PPIs), and opioids prescribed within 30 days before ICI initiation on the treatment duration and survival was assessed. RESULTS: In all, 8870 patients were included in the ICI cohort (NSCLC, 7,128; UC, 960; MM, 782). The patients were prescribed ATBs (33.8%), CSs (47.8%), PPIs (28.5%), and opioids (53.1%) at the baseline. The median overall survival durations were 11.1, 12.2, and 22.1 months in NSCLC, UC, and MM subgroups, respectively, since starting the ICI mostly as second-line (NSCLC and UC) and first-line (MM) therapy. Early progression was observed in 34.2% of the patients. Opioids and CS were strongly associated with poor survival across all cancer types. A high number of concurrent medications was associated with early progression and short survival. Opioid and CS use was associated with poor prognosis in all patients treated with ICIs. However, ATBs and PPIs had a cancer-specific effect on survival. CONCLUSION: A high number of concurrent medications was associated with poor clinical outcomes.

The influence of rurality on melanoma diagnosis in Indiana: A retrospective cohort study.

BACKGROUND: Research from across the United States has shown that rurality is associated with worse melanoma outcomes. In Indiana, nearly a quarter of all residents live in rural counties and an estimated 2180 cases of melanoma will be diagnosed in 2023. AIMS: This study examines how geographical location affects the stage of melanoma diagnosis in Indiana, aiming to identify and address rural health disparities to ultimately ensure equitable care. METHODS AND RESULTS: Demographics and disease characteristics of patients diagnosed with melanoma at Indiana University Health from January 2017 to September 2022 were compared using Students t-tests, Wilcoxon tests, chi-squared or Fisher's exact tests. Patients from rural areas presented with more pathological stage T3 melanomas (15.0% vs. 3.5%, p < 0.001) in contrast to their urban counterparts. Additionally, rural patients presented with fewer clinical stage I melanomas (80.8% vs. 89.3%) and more clinical stage II melanomas (19.2% vs. 8.1%), compared to urban patients, with no stage III (p = 0.028). Concerningly, a significantly higher percentage of the rural group (40.7%) had a personal history of BCC compared to the urban group (22.6%) (p = 0.005) and fewer rural patients (78.0%) compared to urban patients (89.4%) received surgical treatment (p = 0.016). CONCLUSION: Patients from rural counties in Indiana have higher pathological and clinical stage melanoma at diagnosis compared to patients from urban counties. Additionally fewer rural patients receive surgical treatment and may be at higher risk of developing subsequent melanomas.

A study protocol for a feasibility randomised controlled trial investigating videoendoscopic radical inguinal lymphadenectomy versus open radical inguinal lymphadenectomy in patients with penile cancer (VELRAD).

BACKGROUND: Penile cancer is a rare male genital malignancy. Surgical excision of the primary tumour is followed by radical inguinal lymphadenectomy if there is metastatic disease detected by biopsy, fine needle aspiration cytology (FNAC) or following sentinel lymph node biopsy in patients with impalpable disease. However, radical inguinal lymphadenectomy is associated with a high morbidity rate, and there is increasing usage of a videoendoscopic approach as an alternative. METHODS: A pragmatic, UK-wide multicentre feasibility randomised controlled trial (RCT), comparing videoendoscopic radical inguinal lymphadenectomy versus open radical inguinal lymphadenectomy. Patients will be identified and recruited from supraregional multi-disciplinary team meetings (sMDT) and must be aged 18 or over requiring inguinal lymphadenectomy, with no contraindications to surgical intervention for their cancer. Participants will be followed up for 6 months following randomisation. The primary outcome is the ability to recruit patients for randomisation across all selected sites and the rate of loss to follow-up. Other outcomes include acceptability of the trial and intervention to patients and healthcare professionals assessed by qualitative research and obtaining resource utilisation information for health economic analysis. DISCUSSION: There are currently no other published RCTs comparing videoendoscopic versus open radical inguinal lymphadenectomy. Ongoing study is required to determine whether randomising patients to either procedure is feasible and acceptable to patients. The results of this study may determine the design of a subsequent trial. TRIAL REGISTRATION: Clinicaltrials.gov PRS registry, registration number NCT05592639. Date of registration: 13th October 2022, retrospectively registered.

Which factors influence the participation in statutory skin cancer screenings in Germany?

BACKGROUND AND OBJECTIVES: Due to increasing skin cancer incidence, Germany implemented a statutory nationwide routine skin cancer screening (rSCS) in 2008. The present study aims (1) to analyze which patient factors are associated with the participation in rSCS in Germany and (2) to investigate reasons for nonparticipation. PATIENTS AND METHODS: Participants and nonparticipants of rSCS (≥ 35 years) were recruited in routine care in nine dermatological outpatient clinics. Reasons for (non-)participation, knowledge about skin cancer as well as clinical and socioeconomic data were obtained. Stratified by groups, descriptive analyses and binary logistic regression analyses for associations with participation were performed. RESULTS: Of the 294 rSCS participants and 162 non-participants, 46.5% were male with a mean age of 54.5 ± 12.7 years. In total, 87.1% had sunburns in childhood and 47.1% used sunbeds before. Higher age, female gender, previous sunbed use, and concern for and knowledge of skin cancer were significantly associated with previous rSCS participation. Of the non-participants, 46% were unaware of the option for free rSCS and 40% justified their nonparticipation on the basis of feeling healthy. CONCLUSIONS: The reasons for nonparticipation in rSCS, such as sociodemographic characteristics and risk behavior, should be known in order to optimize rSCS programs.

Welche Faktoren beeinflussen die Teilnahme am gesetzlichen Hautkrebsscreenings in Deutschland?: Which factors influence the participation in statutory skin cancer screenings in Germany?

BACKGROUND AND OBJECTIVES: Due to increasing skin cancer incidence, Germany implemented a statutory nationwide routine skin cancer screening (rSCS) in 2008. The present study aims (1) to analyze which patient factors are associated with the participation in rSCS in Germany and (2) to investigate reasons for nonparticipation. PATIENTS AND METHODS: Participants and nonparticipants of rSCS (≥ 35 years) were recruited in routine care in nine dermatological outpatient clinics. Reasons for (non)participation, knowledge about skin cancer as well as clinical and socioeconomic data were obtained. Stratified by groups, descriptive analyses and binary logistic regression analyses for associations with participation were performed. RESULTS: Of the 294 rSCS participants and 162 nonparticipants, 46.5% were male with a mean age of 54.5 ± 12.7 years. In total, 87.1% had sunburns in childhood and 47.1% used sunbeds before. Higher age, female gender, previous sunbed use, and concern for and knowledge of skin cancer were significantly associated with previous rSCS participation. Of the nonparticipants, 46% were unaware of the option for free rSCS and 40% justified their nonparticipation on the basis of feeling healthy. CONCLUSIONS: The reasons for nonparticipation in rSCS, such as sociodemographic characteristics and risk behavior, should be known in order to optimize rSCS programs.

Uveal melanoma incidence and survival analysis in Portugal between 2013 and 2022.

PURPOSE: This study aims to provide a comprehensive overview of the clinical characteristics and epidemiology of uveal melanoma (UM) in the Portuguese population, evaluated at the National Reference Centre (NRC). METHODS: A prospective observational study was conducted, involving patients consecutively diagnosed with UM at the Portuguese NRC between July 2013 and December 2022. The study collected data on demographic and tumour characteristics, clinical staging according to the American Joint Committee on Cancer (AJCC), treatment approaches, local disease control, patient survival, and the occurrence of distant metastases. RESULTS: The study included a total of 316 patients, 53.8% female. The mean age at diagnosis was 61.8±14.2 years, and 75.0% of patients presented with symptoms. The mean annual age-adjusted incidence of uveal melanoma in Portugal between 2014 and 2022 was 2.4 cases per million (95% confidence interval [CI]: 2.1-2.8). For choroidal/ciliary body tumours, the overall cumulative survival and distant metastases-free survival (DMFS) rates at 5 years were 84.9% (95% CI: 78.7-91.1) and 79.4% (95%CI: 72.8-86.0), respectively. Notably, higher AJCC stages at presentation, the need for enucleation, and increased tumour thickness were associated with lower DSS and DMFS rates. CONCLUSION: This study represents the most extensive analysis of UM epidemiology within the Portuguese population. The findings underscore the importance of early diagnosis and treatment in UM, as lower AJCC stages and smaller tumour thickness at diagnosis correlate with improved DSS and DMFS.

Malignant melanoma in the hand: current evidence and recommendations.

Malignant melanoma is the leading cause of death from skin cancer. In spite of significant advances in the management of melanoma with the advent of sentinel lymph node biopsy (SLNB) and adjuvant oncological therapies, the death rate continues to increase worldwide. Melanoma in the hand poses additional diagnostic and management challenges. Consequently, these tend to present at a later stage and are associated with a poorer prognosis. It is imperative that hand surgeons treat any pigmented hand lesion with suspicion to ensure rapid diagnosis and treatment. This article outlines the presentation of melanoma, and how to investigate suspicious pigmented lesions of the hand and digits. It guides hand surgeons in their approach to melanoma of the hand, outlining the multidisciplinary team approach as well as current standard surgical and reconstructive options to optimize outcomes.

Severe acute myositis and myocarditis on initiation of 6-weekly pembrolizumab post-COVID-19 mRNA vaccination.

We describe three cases of critical acute myositis with myocarditis occurring within 22 days of each other at a single institution, all within 1 month of receiving the initial cycle of the anti-PD-1 drug pembrolizumab. Analysis of T cell receptor repertoires from peripheral blood and tissues revealed a high degree of clonal expansion and public clones between cases, with several T cell clones expanded within the skeletal muscle putatively recognizing viral epitopes. All patients had recently received a COVID-19 mRNA booster vaccine prior to treatment and were positive for SARS-CoV2 Spike antibody. In conclusion, we report a series of unusually severe myositis and myocarditis following PD-1 blockade and the COVID-19 mRNA vaccination.

A Choroidal Melanoma With Ciliary Body Involvement in a Young Female.

Choroidal melanoma with ciliary body involvement is rare, especially in young adults and Asians. Here, we report the case of a young, healthy Chinese woman who complained of decreased vision in the left eye for one week. Her ocular examination and imaging were suggestive of choroidal melanoma involving the ciliary body. The patient underwent enucleation of the left eye. Close monitoring was needed, as the involvement of the ciliary body in choroidal melanoma is associated with a high risk of metastasis.

Prognostic gene biomarkers for c-Src inhibitor Si162 sensitivity in melanoma cells.

Background/aim: Early detection and treatment are crucial in combating malignant melanoma. Src is an important therapeutic target in melanoma due to its association with cancer progression. However, developing effective Src-targeting drugs remains challenging and personalized medicine relies on biomarkers and targeted therapies for precise and effective treatment. This study focuses on Si162, a newly synthesized c-Src inhibitor, to identify reliable biomarkers for predicting Si162 sensitivity and explore associated biological characteristics and pathways in melanoma cells. Materials and methods: Primary melanoma cells (M1, M21, M24, M84, M133, M307, and M2025) were obtained from patients diagnosed with melanoma. Si162 cytotoxicity tests were performed using luminescent adenosine triphosphate detection and the half-maximal inhibitory concentration (IC50) values were calculated. Gene expression profiles were analyzed using microarray-based gene expression data. Differentially expressed genes between the resistant and sensitive groups were identified using Pearson correlation analysis. Gene coexpression, interactions, and pathways were investigated through clustering, network, and pathway analyses. Biological functions were examined using the Database for Annotation, Visualization, and Integrated Discovery. Molecular pathways associated with different responses to Si162 were identified using gene set enrichment analysis. The gene expressions were validated using reverse transcription-quantitative polymerase chain reaction. Results: The cells revealed significant differences in response to Si162 based on the IC50 values (p < 0.05). A total of 36 differentially expressed genes associated with Si162 susceptibility were identified. Distinct expression patterns between the sensitive and resistant groups were observed in 9 genes (LRBA, MGMT, CAND1, ADD1, SETD2, CNTN6, FGF18, C18orf25, and RPL13). Coexpression among the differentially expressed genes was highlighted, and 9 genes associated with molecular pathways, including EMT, transforming growth factor-beta (TGF-ß) signaling, and ribosomal protein synthesis, between groups. Genes involved in dysregulated immune response were observed in the resistant group. The involvement of 5 genes (ADD1, CNTN6, FGF18, C18orf25, and RPL13) in Si162 resistance was confirmed through qRT-PCR validation. Conclusion: These findings contribute to our understanding of the underlying biological differences among melanoma cells and suggest potential biomarkers and pathways associated with Si162 response and resistance.

Proposal of a new dermoscopic criterion for pigmented basal cell carcinoma: a multicentre retrospective study.

Dermoscopy is widely used for the diagnosis of skin cancer and it increases the accuracy of basal cell carcinoma (BCC) detection. BCC dermoscopic criteria have been updated and divided into vascular, pigment-related, and non-vascular/non-pigment-related. Our multicenter retrospective study tested a new dermoscopic pigment-related characteristic to detect pigmented BCC (pBCC) [brown homogeneous blotches (BHB)]. Cases of pBCC were collected from the databases of IDI-IRCCS of Rome and from three Italian private dermatology centers. BHB are confined patches of brown uniform pigmentation without dermoscopic features (net, fat fingers, etc.) or other internal dermoscopic structures, except for occasional vascular ones like arborizing vessels or globules/dots. Melanocytic and non-melanocytic controls were used. We reviewed photos of 270 pigmented lesions (female 145; 51.8%), including 90 histopathologically verified pBCC and 180 control cases (90 melanocytic and 90 non-melanocytic). BHB were found in 61 cases of 90 pBCC patients. The results showed a 67.8 sensitivity, 93.3 specificity, 83.6 positive and 85.3 negative predictive values, posLR 10.2, negLR 0.3, odds ratio 29.4, p<0.001. Our multicentre retrospective analysis suggested the BHB may be a novel dermoscopic pBCC diagnosis criterion.

Sunscreen Safety and Efficacy for the Prevention of Cutaneous Neoplasm.

Sunscreen is widely used for ultraviolet radiation protection. Studies validate sun protection factors (SPFs) to prevent ultraviolet (UV)-induced skin changes such as melanoma and squamous cell carcinoma (SCC). Few studies examine sunscreen's impact on endocrine and immune system dysregulation, the production of radical oxygen species, and whether the ingredients deteriorate under prolonged exposure. We present an investigation of sunscreen labels and how ingredients impact sun safety and human health. A review of the literature was conducted using Embase and PubMed to examine sunscreen safety, efficacy, and use to prevent UV-induced skin damage. Increasing sunscreen reapplication, wearing protective clothing, and limiting exposure can reduce the incidence of skin cancer. Inorganic sunscreens form barriers to block UV light, but without titanium dioxide (TiO2), they may not be advantageous due to their low UVA protection. Organic sunscreens absorb into the skin and provide a better feeling after application. Octocrylene and avobenzone are stable and provide UVA and UVB protection with minimal adverse effects. Oxybenzone is harmful to the neuroendocrine system and should be avoided. Titanium dioxide works for broad-spectrum UV protection and offers minimal adverse effects. Octocrylene and avobenzone are organic sunscreen ingredients that also provide a better feeling on the skin after application, which enables higher rates of use. Oxybenzone should be avoided.

The New Media Landscape and Its Effects on Skin Cancer Diagnostics, Prognostics, and Prevention: Scoping Review.

BACKGROUND: The wide availability of web-based sources, including social media (SM), has supported rapid, widespread dissemination of health information. This dissemination can be an asset during public health emergencies; however, it can also present challenges when the information is inaccurate or ill-informed. Of interest, many SM sources discuss cancer, specifically cutaneous melanoma and keratinocyte cancers (basal cell and squamous cell carcinoma). OBJECTIVE: Through a comprehensive and scoping review of the literature, this study aims to gain an actionable perspective of the state of SM information regarding skin cancer diagnostics, prognostics, and prevention. METHODS: We performed a scoping literature review to establish the relationship between SM and skin cancer. A literature search was conducted across MEDLINE, Embase, Cochrane Library, Web of Science, and Scopus from January 2000 to June 2023. The included studies discussed SM and its relationship to and effect on skin cancer. RESULTS: Through the search, 1009 abstracts were initially identified, 188 received full-text review, and 112 met inclusion criteria. The included studies were divided into 7 groupings based on a publication's primary objective: misinformation (n=40, 36%), prevention campaign (n=19, 17%), engagement (n=16, 14%), research (n=12, 11%), education (n=11, 10%), demographics (n=10, 9%), and patient support (n=4, 3%), which were the most common identified themes. CONCLUSIONS: Through this review, we gained a better understanding of the SM environment addressing skin cancer information, and we gained insight into the best practices by which SM could be used to positively influence the health care information ecosystem.

Autoimmunity against melanoma differentiation-associated gene 5 induces interstitial lung disease mimicking dermatomyositis in mice.

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive dermatomyositis (DM) is characterized by amyopathic DM with interstitial lung disease (ILD). Patients with anti-MDA5 antibody-associated ILD frequently develop rapidly progression and present high mortality rate in the acute phase. Here, we established a murine model of ILD mediated by autoimmunity against MDA5. Mice immunized with recombinant murine MDA5 whole protein, accompanied with complete Freund's adjuvant once a week for four times, developed MDA5-reactive T cells and anti-MDA5 antibodies. After acute lung injury induced by intranasal administration of polyinosinic-polycytidylic acid [poly (I:C)] mimicking viral infection, the MDA5-immunized mice developed fibrotic ILD representing prolonged respiratory inflammation accompanied by fibrotic changes 2 wk after poly (I:C)-administration, while the control mice had quickly and completely recovered from the respiratory inflammation. Treatment with anti-CD4 depleting antibody, but not anti-CD8 depleting antibody, suppressed the severity of MDA5-induced fibrotic ILD. Upregulation of interleukin (IL)-6 mRNA, which was temporarily observed in poly (I:C)-treated mice, was prolonged in MDA5-immunized mice. Treatment with anti-IL-6 receptor antibody ameliorated the MDA5-induced fibrotic ILD. These results suggested that autoimmunity against MDA5 exacerbates toll-like receptor 3-mediated acute lung injury, and prolongs inflammation resulting in the development of fibrotic ILD. IL-6 may play a key role initiating ILD in this model.

Genomic deletions explain the generation of alternative BRAF isoforms conferring resistance to MAPK inhibitors in melanoma.

Resistance to MAPK inhibitors (MAPKi), the main cause of relapse in BRAF-mutant melanoma, is associated with the production of alternative BRAF mRNA isoforms (altBRAFs) in up to 30% of patients receiving BRAF inhibitor monotherapy. These altBRAFs have been described as being generated by alternative pre-mRNA splicing, and splicing modulation has been proposed as a therapeutic strategy to overcome resistance. In contrast, we report that altBRAFs are generated through genomic deletions. Using different in vitro models of altBRAF-mediated melanoma resistance, we demonstrate the production of altBRAFs exclusively from the BRAF V600E allele, correlating with corresponding genomic deletions. Genomic deletions are also detected in tumor samples from melanoma and breast cancer patients expressing altBRAFs. Along with the identification of altBRAFs in BRAF wild-type and in MAPKi-naive melanoma samples, our results represent a major shift in our understanding of mechanisms leading to the generation of BRAF transcripts variants associated with resistance in melanoma.

Vascular mimicry as a facilitator of melanoma brain metastasis.

Melanoma has the highest propensity among solid tumors to metastasize to the brain. Melanoma brain metastases (MBM) are a leading cause of death in melanoma and affect 40-60% of patients with late-stage disease. Therefore, uncovering the molecular mechanisms behind MBM is necessary to enhance therapeutic interventions. Vascular mimicry (VM) is a form of neovascularization linked to invasion, increased risk of metastasis, and poor prognosis in many tumor types, but its significance in MBM remains poorly understood. We found that VM density is elevated in MBM compared to paired extracranial specimens and is associated with tumor volume and CNS edema. In addition, our studies indicate a relevant role of YAP and TAZ, two transcriptional co-factors scarcely studied in melanoma, in tumor cell-vasculogenesis and in brain metastasis. We recently demonstrated activation of the Hippo tumor suppressor pathway and increased degradation of its downstream targets YAP and TAZ in a metastasis impaired cell line model. In the current study we establish the utility of anti-YAP/TAZ therapy in mouse models of metastatic melanoma whereby treatment effectively inhibits VM and prolongs survival of mice with MBM. The data presented herein suggest that VM may be an important and targetable mechanism in melanoma and that VM inhibition might be useful for treating MBM, an area of high unmet clinical need, thus having important implications for future treatment regimens for these patients.

Transcriptome-Based Treatment for Melanoma With Brain Metastasis: A Case Report.

Malignant melanoma with brain metastasis has a high mortality rate. New approaches for diagnosis and treatment are urgently required to improve prognosis. Here we present a 60-year-old male with metastatic melanoma to the brain. Using a transcriptomics pipeline, we analyzed whole blood and resected tumor tissue, identifying enriched gene expression biomarkers and pathways - including seven upregulated ( BRAF, CDK4, EIF1AX, IK, NRAS, PIK3R2, and TP53) and 11 downregulated (CASP8, CDK10, CDKN2A, CTLA4, GNA11, HERC2, IRF4, MC1R, PLA2G6, RREB1, and TPCN2) genes in the blood (across 15 pathways), showing 14% enrichment, and 16 upregulated (CCND1, CDK4, CTLA4, EIF1AX, IK, IRF4, MITF, NRAS, PIK3CB, PIK3R2, PMEL, RREB1, SLC45A2, SOX10, TYR, and TYRP1) and three downregulated ( GNA11, KITLG, and PLA2G6) genes in tissue (across 17 pathways), showing 33% enrichment, with five shared markers and 12 shared pathways. The model connected CDK4 pathway overactivity observed in both samples to inhibitors like ribociclib, abemaciclib, and palbociclib as putative treatments. By enabling objective personalized therapy selection, this approach shows great promise for advancing patient outcomes.

Society for Immunotherapy of Cancer (SITC) recommendations on intratumoral immunotherapy clinical trials (IICT): from premalignant to metastatic disease.

BACKGROUND: Intratumorally delivered immunotherapies have the potential to favorably alter the local tumor microenvironment and may stimulate systemic host immunity, offering an alternative or adjunct to other local and systemic treatments. Despite their potential, these therapies have had limited success in late-phase trials for advanced cancer resulting in few formal approvals. The Society for Immunotherapy of Cancer (SITC) convened a panel of experts to determine how to design clinical trials with the greatest chance of demonstrating the benefits of intratumoral immunotherapy for patients with cancers across all stages of pathogenesis. METHODS: An Intratumoral Immunotherapy Clinical Trials Expert Panel composed of international key stakeholders from academia and industry was assembled. A multiple choice/free response survey was distributed to the panel, and the results of this survey were discussed during a half-day consensus meeting. Key discussion points are summarized in the following manuscript. RESULTS: The panel determined unique clinical trial designs tailored to different stages of cancer development-from premalignant to unresectable/metastatic-that can maximize the chance of capturing the effect of intratumoral immunotherapies. Design elements discussed included study type, patient stratification and exclusion criteria, indications of randomization, study arm determination, endpoints, biological sample collection, and response assessment with biomarkers and imaging. Populations to prioritize for the study of intratumoral immunotherapy, including stage, type of cancer and line of treatment, were also discussed along with common barriers to the development of these local treatments. CONCLUSIONS: The SITC Intratumoral Immunotherapy Clinical Trials Expert Panel has identified key considerations for the design and implementation of studies that have the greatest potential to capture the effect of intratumorally delivered immunotherapies. With more effective and standardized trial designs, the potential of intratumoral immunotherapy can be realized and lead to regulatory approvals that will extend the benefit of these local treatments to the patients who need them the most.

Modulating DNA damage response in uveal melanoma through embryonic stem cell microenvironment.

BACKGROUND: Uveal melanoma (UVM) is the most common primary intraocular tumor in adults, with a median survival of 4-5 months following metastasis. DNA damage response (DDR) upregulation in UVM, which could be linked to its frequent activation of the PI3K/AKT pathway, contributes to its treatment resistance. We have reported that embryonic stem cell microenvironments (ESCMe) can revert cancer cells to less aggressive states through downregulation of the PI3K signaling, showing promise in modulating the DDR of UVM. METHODS: Since nonhomologous end joining (NHEJ) is the main DNA repair mechanism in UVM, this study utilized gene expression analysis and survival prognosis analysis to investigate the role of NHEJ-related genes in UVM based on public databases. Xenograft mouse models were established to assess the therapeutic potential of ESC transplantation and exposure to ESC-conditioned medium (ESC-CM) on key DNA repair pathways in UVM. Quantitative PCR and immunohistochemistry were used to analyze NHEJ pathway-related gene expression in UVM and surrounding normal tissues. Apoptosis in UVM tissues was evaluated using the TUNEL assay. RESULTS: PRKDC, KU70, XRCC5, LIG4 and PARP1 showed significant correlations with UM progression. High expression of PRKDC and XRCC5 predicted poorer overall survival, while low PARP1 and XRCC6 expression predicted better disease-free survival in UVM patients. ESCMe treatment significantly inhibited the NHEJ pathway transcriptionally and translationally and promoted apoptosis in tumor tissues in mice bearing UVM. Furthermore, ESC transplantation enhanced DDR activities in surrounding normal cells, potentially mitigating the side effects of cancer therapy. Notably, direct cell-to-cell contact with ESCs was more effective than their secreted factors in regulating the NHEJ pathway. CONCLUSIONS: Our results suggest that NHEJ-related genes might serve as prognostic markers and therapeutic targets in UVM. These findings support the therapeutic potential of ESC-based therapy in enhancing UVM sensitivity to radiochemotherapy and improving treatment outcomes while minimizing damage to healthy cells.

Case report: MRI and CT imaging features of a melanocytic tumour affecting a cervical vertebra in an adult dog, and review of differential diagnosis for T1W-hyperintense lesions.

A 7-year-old Lhasa Apso presented with a history of left thoracic limb lameness and neck pain. Magnetic resonance imaging revealed a well-defined, extradural lesion that was hyperintense on T1-weighted (T1W) images and isointense on T2-weighted (T2W) images and T2* images located at the left lamina of the C4 vertebra. Computed tomography showed an isoattenuating and contrast-enhancing mass centered on the left C4 vertebral lamina with associated osteolysis. The mass was surgically debulked, and histopathology revealed a malignant melanocytic tumour. The patient recovered completely and received radiotherapy and three doses of the melanoma vaccine as adjunctive treatment. Eighteen months following treatment, the patient presented with neck pain again, but further investigations were declined at this stage, and the patient was euthanised. To the author's knowledge, this is the first case report describing the imaging characteristics of a cervical extradural melanocytic tumour in a dog. This case illustrates the MRI and CT imaging features and treatment of a canine melanocytic tumour of the cervical vertebrae.