Melanoma is a highly aggressive skin cancer with survival rates varying significantly based on stage and genomic characteristics. While localized melanoma has favorable outcomes, metastatic melanoma is associated with poor prognosis and limited treatment options. Radiotherapy (RT), one of the most commonly used cancer treatments, is less effective in melanoma due to its intrinsic radioresistance. This review discusses the current knowledge about the biological mechanisms contributing to melanoma radioresistance, including the role of cancer stem cells (CSCs), DNA repair mechanisms, hypoxia, altered metabolism, and melanin production. It also examines preclinical and clinical studies on novel therapeutic approaches, such as targeting CSC pathways, inhibiting DNA repair, modulating hypoxia-induced metabolic shifts, and combining RT with immunotherapies or targeted therapies. Promising strategies, such as RT-induced immune responses and advanced RT techniques, show the potential to overcome resistance. However, melanoma’s heterogeneity and the limited clinical validation of these approaches remain significant challenges. Integrated therapeutic strategies targeting the multifaceted mechanisms of melanoma radioresistance are essential to improve treatment outcomes. Further clinical validation and personalized approaches are needed to address the heterogeneity of melanoma and enhance the efficacy of novel interventions.

Background: Patients with steroid-refractory intestinal acute graft-versus-host disease (aGvHD) and bronchiolitis obliterans syndrome (BOS) represent a population with a high need for alternative and effective treatment options. Methods: We report real-life data from 18 patients treated with extracorporeal photopheresis (ECP). This cohort consisted of nine patients with steroid-refractory intestinal aGvHD and nine patients with BOS. Results: We document partial or complete clinical response and reduction of symptoms in half of the patients with intestinal acute GvHD and patients with BOS treated ECP. Responding patients tended to stay on treatment longer. In patients with BOS, stabilization of lung function and forced expiratory volume was observed, whereas, less abdominal pain, less diarrhea, and a reduction of systemic corticosteroids were seen in patients with intestinal acute GvHD. Conclusions: ECP might not only abrogate symptoms but also reduce mortality caused by complications from high-dose steroid treatment. Taken together, ECP offers a serious treatment avenue for patients with steroid-refractory intestinal acute GvHD and BOS.

Background: Tamoxifen-adapted MCF-7-Tam cells represent an in-vitro model for acquired tamoxifen resistance, which is still a problem in clinics. We here investigated the correlation of microRNA-, mRNA- and eukaryotic initiation factors (eIFs) expression in this model. Methods: MicroRNA- and gene expression were analyzed by nCounter and qRT-PCR technology; eIFs by Western blotting. Protein translation mode was determined using a reporter gene assay. Cells were transfected with a miR-1972-mimic. Results: miR-181b-5p,-3p and miR-455-5p were up-, miR-375, and miR-1972 down-regulated and are significant in survival analysis. About 5% of the predicted target genes were significantly altered. Pathway enrichment analysis suggested a contribution of the FoxO1 pathway. The ratio of polio-IRES driven to cap-dependent protein translation shifted towards cap-dependent initiation. Protein expression of eIF2A, -4G, -4H and -6 decreased, whereas eIF3H was higher in MCF-7-Tam. Significant correlations between tamoxifen-regulated miRNAs and eIFs were found in representative breast cancer cell lines. Transfection with a miR-1972-mimic reverses tamoxifen-induced expression for a subset of genes and increased proliferation in MCF-7, but reduced proliferation in MCF-7-Tam, especially in the presence of 4OH-tamoxifen. Migration was inhibited in MCF-7-Tam cells. Translation mode remained unaffected. Conclusions: miR-1972 contributes to the orchestration of gene-expression and physiological consequences of tamoxifen adaption.

Resistance to chemotherapy is ultimately responsible for the majority of AML-related deaths, making the identification of resistance pathways a high priority. Transcriptomics approaches can be used to identify genes regulated at the level of transcription or mRNA stability but miss microRNA-mediated changes in translation, which are known to play a role in chemo-resistance. To address this, we compared miRNA profiles in paired chemo-sensitive and chemo-resistant subclones of HL60 cells and used a bioinformatics approach to predict affected pathways. From a total of 38 KEGG pathways implicated, TGF-β/activin family signaling was selected for further study. Chemo-resistant HL60 cells showed an increased TGF-β response but were not rendered chemo-sensitive by specific inhibitors. Differential pathway expression in primary AML samples was then investigated at the RNA level using publically available gene expression data in the TGCA database and by longitudinal analysis of pre- and post-resistance samples available from a limited number of patients. This confirmed differential expression and activity of the TGF-β family signaling pathway upon relapse and revealed that the expression of TGF-β and activin signaling genes at diagnosis was associated with overall survival. Our focus on a matched pair of cytarabine sensitive and resistant sublines to identify miRNAs that are associated specifically with resistance, coupled with the use of pathway analysis to rank predicted targets, has thus identified the activin/TGF-β signaling cascade as a potential target for overcoming resistance in AML.

Background: Patients with hemato-oncological malignancies may respond insufficiently to vaccination, especially in terms of antibody titer. The antibody response depends on the type of malignancy as well as the type and timing of treatment. We intended to evaluate this using real-world data from patients of our regional hospital. This study also considers the role of immune status, including T-cell activation markers, in predicting vaccination success. Methods: Seventeen patients of our hospital having a hematological malignancy were included in this study, including myeloma, lymphoma, as well as acute myeloid leukemia (AML) and chronic lymphoid leukemia (CLL). All patients were vaccinated against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) using Tozinameran following current recommendations. Circulating antibodies directed against the spike protein of SARS-CoV-2 were determined by a commercial immune assay. Immune status was determined from peripheral blood by flow cytometry. Both parameters were followed in fifteen patients who provided sufficient follow-up data for up to one year. Patients were categorized as responders or non-responders, and differences in diagnosis, treatment, and immune status were analyzed. Results: Antibody response depended on both diagnosis and treatment. Active treatment directed against B-cells, such as anti-Cluster of Differentiation 20 (CD20) therapy, was associated with weak seroconversion. For CD38-as well as proteasome-directed therapies, the data suggest that responders as well as non-responders exist. Notably, low peripheral B-cell numbers and high CD3+HLADR+cell counts correlated with weak seroconversion upon vaccination. Conclusions: We suggest that peripheral immune status can be applied as a predictive biomarker for seroconversion upon vaccinations.

Introduction: Acute myeloid leukemia (AML) is a biologically heterogeneous, malignant disease of the hematopoietic system. In ~10% of AML cases, the full- length isoform (p42) of the transcription factor CCAAT/enhancer binding protein alpha (C/EBPα), an essential regulator of...