Onco, Volume 6, Issue 1 (March 2026) – 17 articles

Background: DNA methylation profiling has become an important diagnostic tool in pediatric neuro-oncology, particularly for tumors with overlapping morphology or unusual immunophenotypes. Methods: We report four pediatric brain tumor cases evaluated by histopathology and immunohistochemistry, supplemented by targeted next-generation sequencing (NGS) and DNA methylation profiling using the DKFZ Brain Tumor Classifier (v12.8); one case also underwent DKFZ Sarcoma Classifier analysis (v13.2). Results: Methylation profiling provided clinically meaningful diagnostic insights across all cases. In two patients, methylation results supported integrated interpretation in diagnostically challenging settings without changing management. In two cases, methylation profiling prompted major diagnostic revisions with significant therapeutic consequences: (i) a tumor initially diagnosed as atypical teratoid/rhabdoid tumor was reclassified as CNS Ewing sarcoma, confirmed by an EWSR1-FLI1 fusion and immunophenotype, leading to a change to Ewing-based therapy; and (ii) a tumor interpreted as high-grade astrocytoma/glioblastoma was reclassified as a CNS tumor with BCOR internal tandem duplication, enabling a curative-intent approach and revised prognostic counseling. Conclusions: These cases illustrate that DNA methylation profiling can complement histopathology, resolve diagnostically ambiguous tumors, and in selected patients substantially alter treatment decisions and expected outcomes. Early integration of methylome profiling may improve precision diagnostics and reduce the risk of inappropriate therapy in pediatric brain tumors. Full article

Background/Objectives: Chondrosarcoma, glioblastoma, acute myeloid leukemia, chronic lymphocytic leukemia, and cholangiocarcinoma cancers all contain mutations in the gene isocitrate dehydrogenase 2 (IDH2). The mutant IDH2 enzyme metabolizes alpha-ketoglutarate (αKG) into the potent oncometabolite D-2-hydroxyglutarate (D2HG) in the mitochondria of these cancers, leading to altered cellular metabolism. Emerging evidence suggests that mitochondrial transfer between cancer and recipient cells represents an important form of intercellular communication that may influence cellular metabolism. The presence of intercellular TNTs between IDH2-mutant chondrosarcoma cells motivated an investigation into mitochondria-associated physiological changes occurring during an intercellular exchange with immune cells. A mitochondrial transfer is a two-way process, and we hypothesized that mitochondria-associated material derived from IDH2-mutant chondrosarcoma cells is exchanged with normal cells through TNTs. We further hypothesized that disruption of the actin cytoskeleton will inhibit this transfer. Accordingly, our objectives were to (1) quantify the extent and directionality of the mitochondrial exchange between IDH2-mutant cells and wild-type cells and to modulate this process via cytoskeletal inhibitors, and (2) measure the metabolic changes associated with the coculture and mitochondrial exchange. Methods: IDH2-mutant chondrosarcoma cells were cocultured with immune cells in vitro to quantify the extent and directionality of the mitochondrial exchange, and cytochalasin B was used as a cytoskeletal inhibitor to disrupt actin-dependent transfer. Metabolic changes associated with coculture and mitochondrial exchange were assessed using Seahorse extracellular flux analysis. Results: The experimental data presented here demonstrate a bidirectional exchange of mitochondria-associated material between IDH2-mutant chondrosarcoma cells and immune cells in vitro, accompanied by metabolic alterations in both cell types. Conclusions: These findings advance our understanding of intercellular communication in the tumor microenvironment and provide a foundation for future studies examining the functional and therapeutic relevance of a mitochondrial exchange in IDH2-mutant cancers. Full article

Hepatocellular carcinoma (HCC) exhibits a striking male predominance, particularly in Hepatitis B Virus (HBV) endemic regions. While lifestyle factors and estrogen protection are traditional explanations, they fail to fully account for this disparity. This review elucidates the molecular mechanisms driving this gender gap, focusing on the interplay between the Androgen Receptor (AR), viral replication, and the suppression of NKG2D-mediated immune surveillance. We synthesized experimental and clinical findings linking AR signaling, the viral protein HBx, and the regulation of NKG2D ligands (MICA/MICB). Current evidence identifies a positive feedback loop where AR enhances HBV replication, while HBx amplifies AR activity. Crucially, this axis systematically dismantles innate immunity: AR signaling represses MICA/B transcription via miRNA networks and upregulates ADAM metalloproteases, leading to ligand shedding and the release of soluble MICA (sMICA), effectively blinding Natural Killer (NK) cells. We propose that historical failures of anti-androgen monotherapy likely stemmed from ignoring this immune modulation. Consequently, targeting the AR-NKG2D axis represents a promising strategy to sensitize tumors to immunotherapy, suggesting that future therapeutic approaches should combine AR modulation with immune checkpoint inhibitors or shedding-blockade. Full article

Background: Cervical cancer is the second most prevalent malignancy among South African women, with high-risk human papillomavirus (HPV) infection as a critical risk factor. HPV plays a central role in cervical carcinogenesis, particularly in high-grade squamous intraepithelial lesions (HSIL). Increased programmed death ligand 1 (PD-L1) expression has been implicated in cervical carcinoma tumorigenesis. Using immunohistochemistry, this study investigated the correlation between high-risk HPV-driven cervical intraepithelial neoplasia (CIN) and PD-L1 expression. Methods: An analytical cross-sectional study was conducted on archival tissue from the Department of Anatomical Pathology, University of Pretoria (2018–2021). Formalin-fixed paraffin-embedded tissues from loop electrosurgical excisions, cone biopsies, punch biopsies, and polypectomies were analysed. PD-L1 expression was assessed using the combined proportion score (CPS). Three pathologists independently evaluated histological grade, p16 immunohistochemistry, and PD-L1 expression. Results: Among 108 cases (mean age: 37.36 years), 89.8% were CIN 3, 9.3% CIN 2, and 0.9% CIN 2–3. p16 was positive in 97.2% of cases. PD-L1 expression (CPS ≥ 1) was observed in 9.3% of cases, with a mean CPS of 1.57%. No significant association was found between PD-L1 expression and CIN grade (p = 0.6433, Cramer’s V = 0.1191) or between PD-L1 and p16 positivity (p = 1, Cramer’s V = 0.05976). Conclusions: This study demonstrates no correlation between PD-L1 expression and high-risk HPV-driven high-grade CIN. These findings suggest that immune checkpoint inhibition targeting PD-L1 may have limited therapeutic relevance in HSIL among South African women. Full article

Background/Objectives: Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy characterized by late diagnosis, early metastasis, and poor response to therapy. Liquid biopsy approaches, including circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), and exosomes, offer a minimally invasive method to monitor tumor burden, progression, and treatment response in real time. This review aims to synthesize recent findings on CTCs in PDAC, evaluate detection technologies, and explore their clinical and translational potential. Methods: We conducted a comprehensive literature search using PubMed and Google Scholar, focusing on original studies and reviews published within the past 15 years. Articles were selected based on relevance to CTC biology, detection methods, clinical correlations, and integration with other biomarkers. Attention was paid to studies published since 2018 and landmark earlier works. Results: CTCs are detectable in PDAC patients and are consistently associated with worse survival and higher recurrence rates. However, detection sensitivity varies widely by method. EpCAM-based platforms like CellSearch^® detect CTCs in ~7–48% of cases, while newer size-based and microfluidic approaches report rates above 75%. CTCs exhibit epithelial–mesenchymal and stem-like phenotypes and can form clusters with high metastatic potential. Recent studies demonstrate molecular heterogeneity and show that CTC-derived organoids are feasible for functional studies. Nonetheless, technical variability and the lack of standardization remain major obstacles. Conclusions: CTCs represent a promising biomarker for prognosis and treatment monitoring in PDAC. Further refinement of enrichment techniques, molecular profiling strategies, and prospective clinical validation are needed to integrate CTC assays into routine PDAC management. Full article

The innate immune system’s core sensor, the NLRP3 inflammasome (Nucleotide-binding Oligomerization Domain, Leucine-rich Repeat, and Pyrin Domain-Containing Protein 3), is a pivotal multi-protein complex that detects cellular danger and microbial threats. While its activation is fundamental for host defense, chronic dysregulation of NLRP3 is a central driver of pathology in diverse diseases, ranging from neurodegeneration to cancer. This review comprehensively examines the complex and often paradoxical roles of the NLRP3 inflammasome in these two distinct domains. In neurodegenerative disorders, including Alzheimer’s and Parkinson’s, aberrant NLRP3 activation drives persistent neuroinflammation, leading to synaptic dysfunction and neuronal loss through the sustained release of mature IL-1β and IL-18. Conversely, NLRP3 exhibits a striking bimodal role in oncology; it can promote tumorigenesis by fueling chronic inflammation, metastasis, and immune evasion in certain tumor microenvironments, yet simultaneously enhances anti-tumor immunity and pyroptotic cell death in other specific contexts. This context-dependent function highlights a critical therapeutic challenge. We delineate the shared molecular pathways, contrast disease-specific outcomes, and the current landscape of therapeutic strategies aimed at modulating NLRP3. Understanding the nuanced role of the inflammasome offers novel insights into the convergence of chronic inflammation, neurodegeneration, and tumor biology, and holds promise for the development of targeted, context-dependent therapies with dual clinical applications. Full article

Objectives. Pancreatic cancer remains one of the most lethal malignancies, and the lack of effective therapies highlights the need for novel treatment strategies. In this study, we evaluated the antitumor potential of the attenuated Streptococcus pyogenes strain GURSA1—engineered to knockout the M protein completely—in a murine model of orthotopically transplanted pancreatic ductal adenocarcinoma. Methods. Female C57Bl/6 mice received intratumoral injections of GURSA1 at doses of 5 × 10⁵ or 1 × 10⁶ CFU per animal. Animal survival, body weight, tumor engraftment, metastasis intensity, tumor mass and volume, and hematological, biochemical, histological, and microbiological parameters were assessed. Results. Intratumoral administration of GURSA1 produced dose-dependent antitumor effects on tumor growth and metastatic burden, but did not result in a statistically significant survival benefit. The strain reduced tumor engraftment, the overall metastasis score, and the incidence of hemorrhagic ascites, while also decreasing tumor mass and volume, with the strongest effects observed at a dose of 1 × 10⁶ CFU. Treatment increased platelet counts and reduced urea and ALT levels toward values observed in intact mice, without affecting anemia, neutrophilia, or changes in AST, alkaline phosphatase, glucose, and total protein levels. Conclusions. These findings demonstrate that GURSA1 attenuates partial reduction in primary tumor burden in vivo and support further investigation of this strain as a potential oncolytic agent. Full article

Small cell lung cancer (SCLC) is a highly aggressive neuroendocrine disease marked by rapid growth, early metastatic spread, and poor outcomes. The addition of immune checkpoint inhibitors (ICIs) targeting the PD-1/PD-L1 axis to first-line chemotherapy has recently reshaped the treatment landscape for extensive-stage SCLC (ES-SCLC); however, the resulting survival gains remain modest compared with non-small lung cancer (NSCLC). This review explores the molecular features of the SCLC immune landscape that contribute to its predominantly “cold” tumor phenotype, including low MHC class I expression, T-cell exhaustion, and a profoundly immunosuppressive tumor microenvironment (TME). We summarize key clinical findings from landmark trials and examine mechanisms of both primary and acquired resistance against ICIs in SCLC. In addition, we have reviewed the growing role of precision medicine in SCLC, including molecular subtyping (SCLC-A, -N, -P, and -I) and the development of next-generation immunotherapies such as bispecific T-cell engagers (BiTEs), B7-H3, targeted therapy, and antibody–drug conjugates. By combining existing clinical evidence with new molecular insights, this review article presents strategies to overcome the existing therapeutic plateau and enhance personalized immunotherapy approaches in SCLC. Full article

Cervical cancer is strongly associated with persistent infection by high-risk human papillomavirus (HPV). Recent advances in immunotherapy have redefined the therapeutic landscape of this disease. We aim to review the biological rationale, clinical evidence, and biomarker standardization supporting the use of immune checkpoint inhibitors (ICIs) in cervical cancer. A comprehensive review of recent literature and pivotal phase II–III clinical trials was performed, focusing on the PD-1/PD-L1 and CTLA-4 pathways, mechanisms of immune evasion, and predictive biomarkers. Persistent HPV infection leads to immune dysregulation and PD-L1 upregulation through E6/E7-mediated activation of the PI3K/AKT/mTOR and JAK/STAT pathways. ICIs have demonstrated significant improvements in overall survival, progression-free survival, and objective response rates in advanced and recurrent disease. PD-L1 immunohistochemistry using standardized assays such as 22C3 pharmDx and SP263 remains the key biomarker for treatment selection, while emerging molecular markers (TMB, MSI, HLA-I expression) are under investigation. Immunotherapy represents a major step forward in cervical cancer management, integrating molecular diagnostics and immune modulation into clinical practice. Continued efforts to refine biomarkers, optimize combination strategies, and expand global access will be essential to achieve equitable outcomes and disease elimination goals. Full article

Introduction: Radiotherapy plays a critical role in the management of head and neck squamous-cell carcinoma (HNSCC); however, the influence of overall treatment time on patient outcomes remains an area of ongoing investigation. The use of radiation, either in conjunction with concurrent chemotherapy or on its own, is crucial when treating HNSCC. Despite the longstanding hypothesis that treatment gaps may adversely affect tumor response and overall survival, there is a paucity of literature on this particular area. This study aims to bridge the knowledge gap and assess the correlation of treatment gaps on recurrences in HNSCC patients. Materials and Methodology: This retrospective study is based on an analysis of data obtained from a single institution between 2017 and 2021. Patients were selected on the basis of the presence of treatment gaps. Data were extracted from medical records and analyzed to evaluate the association between overall treatment time and various patient and treatment-related factors. Various factors thought to contribute to treatment gaps, such as age, TNM Stage, radiation dose, and use of concurrent chemotherapy, were also examined. Results: A total of 212 patients with treatment gaps were evaluated. Of these, 80 individuals experienced recurrences. It was observed that compared to distant metastases, locoregional failure was more frequent (n = 2, 4.2% vs. n = 45, 95.74%). The patients underwent both adjuvant and definitive therapy and were treated with a dose range of 60–70 Gy and concurrent cisplatin chemotherapy. It was noticed that this cohort had a range of 4–43 days of treatment gaps. Notably, 19 out of 47 patients had treatment gaps ≤ 5 days, while 28 out of 47 had gaps exceeding 5 days. It was also observed that patients with treatment gaps of >5 days had poorer quality of life and overall survival. Conclusions: This study identified that the Overall Treatment Time (OTT) had a strong statistical correlation with the development of recurrences. Further, the age of the patient, presence of neutropenia and the duration of the treatment gap were also identified to significantly correlate with the chance of developing recurrences. Full article

Most clinical cancer therapy trials do not specifically consider the effect of patient age on treatment outcomes, and many even exclude older individuals. This is despite the fact that solid cancers are age-associated diseases and that there are many shared hallmarks between biological ageing and cancer. Thus, there is an increasing awareness of the serious gaps remaining in our knowledge of how older adults respond to cancer treatments, particularly immunotherapies. Emerging evidence suggests that it is not only the physiological and immunological changes associated with chronological ageing that impacts cancer treatment, but also those heterogeneous differences that impact treatment outcomes, such as frailty, comorbidities, and more generally, biological ageing. Importantly, it remains unclear which of these factors are negative or positive contributors, as has been illuminated by recent evidence pertaining to the incidence and severity of immune-related adverse events and survival. Much of our information on older patients in this context is essentially anecdotal, mostly deriving from the treatment of older adults in real-world practice or clinical trials that happened to include some older patients. Given the lack of comprehensive articles on the heterogeneity of ageing as a core determinant of cancer treatment outcomes, we briefly consider the state of the art of cancer research and treatment in the older patient, with an emphasis on immunotherapy and geriatric oncology. Full article

In the context of advanced BRAF-mutant melanoma, the treatment landscape has undergone a paradigm shift due to the impact of immune checkpoint inhibitors and BRAF/MEK inhibitors. This article presents three clinically illustrative melanoma cases that served as focal points for in-depth discussions during 12 expert meetings held across Spain. These include a treatment-naïve metastatic melanoma patient, a patient experiencing a recurrence while on anti-PD-1 adjuvant therapy, and a third patient whose melanoma relapsed ≥6 months after the end of adjuvant therapy. The discussions revolved around optimal treatment sequencing, emphasizing the challenges and alternatives discussed in each scenario. The common view aligned towards a nuanced approach that involves navigating the complexities of treatment choices. The conclusions underscore the need for personalized therapeutic strategies and highlight the ongoing challenge of refining real-life evidence-based algorithms for the management of metastatic BRAF-mutant melanoma. Full article

Background: The belief that “sugar feeds cancer” is widespread and has strongly influenced public perceptions, patient behavior, and dietary recommendations, despite uncertainty regarding its scientific validity. This belief largely stems from misinterpretation of the Warburg effect, which describes altered glucose metabolism in cancer cells rather than dietary sugar dependence. The objective of this review was to critically evaluate whether dietary sugar intake directly contributes to cancer development or progression by examining the totality of epidemiological, experimental, and mechanistic evidence. Methods: We conducted a narrative review of human epidemiological studies, experimental animal and cell-based models, and mechanistic investigations published between 1980 and July 2025. Evidence was synthesized across cancer types, sugar sources, and biological pathways, with careful consideration of study design, exposure relevance, and key confounders, including obesity, insulin resistance, and overall dietary patterns. Results: Across cancer types, epidemiological evidence showed predominantly null or inconsistent associations between sugar intake and cancer risk or outcomes, with positive findings largely confined to metabolically susceptible subgroups and often attenuated after adjustment for adiposity and energy intake. Experimental studies suggested potential tumor-promoting effects under non-physiological conditions, while mechanistic data indicated that sugar influences cancer risk indirectly through insulin signaling, inflammation, and metabolic dysfunction rather than direct tumor fueling. Conclusions: Current evidence does not support the hypothesis that dietary sugar directly “feeds” cancer in humans. Overemphasis on sugar avoidance risks nutritional and psychological harm, particularly among cancer patients. Evidence-based guidance should prioritize overall dietary quality, metabolic health, and patient well-being rather than isolated sugar restriction. Full article

Immunotherapy has revolutionized the management of patients with cancer. Immune checkpoint inhibition (ICI) is a promising treatment option that targets the molecular mechanisms that cancer cells exploit to prevent immune-mediated elimination. ICI therapy can cause exceptional long-term tumor remissions, in some cases, even after treatment discontinuation. Despite its success, many patients acquire resistance or fail to respond due to immune escape mechanisms mediated by the tumor and its microenvironment. Pre-existing immunity status of individuals seems to play a fundamental role in immunotherapy response and eventually tumor progression, as it orchestrates tumor-immune interactions. Different immune cell subsets, both in the tumor microenvironment and the peripheral blood, are established mediators that contribute to immune escape in various tumor types. Based on these findings, the elucidation of the mechanisms implicated in the regulation of these immune cells has become a priority for investigators focused on improving the efficacy of ICI. This will be essential for identifying responders as well as for developing novel therapeutic modalities to improve clinical outcomes. Herein, we summarize preclinical and clinical evidence proposing a predictive role of pre-existing immunity for clinical responses to immunotherapies. Full article

Background: There are approximately 5.4 M basal cell (BCC) and squamous cell (SCC) carcinomas diagnosed each year, and the number is increasing. Currently, the gold standard for skin cancer diagnosis is histopathology, which requires the surgical excision of the tumor followed by pathological evaluation of a tissue biopsy. The three-dimensional (3D) nature of human tissue suggests that two-dimensional (2D) cross sections may be insufficient in some cases to represent the complex structure due to sampling bias. There is a need for new techniques that can be used to classify skin lesion types and margins noninvasively. Methods: We use optical coherence tomography volume scan images and AI to noninvasively create 3D images of basal cell and squamous cell carcinomas. Results: Three-dimensional optical coherence tomography images can be broken down into a series of cross sections that can be classified as benign or cancerous using convolutional neural network models developed in this study. These models can identify cancerous regions as well as clear edges. Cancerous regions can also be verified based on visual review of the color-coded images and the loss of the green and blue subchannel pixel intensities. Conclusions: Three-dimensional optical coherence tomography cross sections of cancerous lesions can be collected noninvasively, and AI can be used to classify skin lesions and detect clear lesion edges. These images may provide a means to speed up treatment and promote better patient screening, especially in older patients who will likely develop several lesions as they age. Full article

The tumor microenvironment (TME) plays an important role in the development, progression, and treatment response of pediatric cancers, yet remains less elucidated compared to adult malignancies. Pediatric tumors are unique with a low mutational burden, an immature immune landscape, and unique stromal interactions. The resultant “cold” immune microenvironments limits the effectiveness of conventional immunotherapies. This review summarizes the key cellular and non-cellular components of the pediatric TME—including T cells, NK cells, tumor-associated macrophages, cancer-associated fibroblasts, extracellular matrix remodeling, angiogenesis, and hypoxia—and describes how these elements shape tumor behavior and therapy resistance. The role of TME in common pediatric cancers like leukemia, lymphoma, neuroblastoma, brain tumors, renal tumors, and sarcomas is discussed. Emerging therapeutic strategies targeting immune checkpoints, macrophage polarization, angiogenic pathways, and stromal barriers are discussed. Full article

Background: Melanoma and triple-negative breast cancer (TNBC) are the most aggressive skin and breast cancers, often diagnosed at late stages with limited treatment options. The melanoma-associated antigen melanotransferrin (MTf) is overexpressed in these solid tumors, where it drives tumorigenesis, progression, and chemoresistance. Its inhibition correlates with tumor regression, making MTf a promising therapeutic target. This study aimed to develop a novel, selectively targeted antibody–drug conjugate (ADC) against MTf-expressing melanoma and TNBC cancer cells using SNAP-tag fusion protein conjugation technology. Methods: We generated an L49(scFv)-SNAP-tag antibody fusion protein engineered through the genetic fusion of a humanized anti-MTf single-chain variable fragment (scFv) with a SNAP-tag fusion protein capable of site-specific self-labelling with O⁶-benzylguanine (BG) modified substrates in 1:1 stoichiometry. Binding and internalization of the conjugate labeled with BG-Alexa 488 (L49(scFv)-SNAP-Alexa488) were assessed by confocal microscopy and flow cytometry in MTf-overexpressing cell lines. Cytotoxicity was evaluated using the cell viability XTT assay after conjugating the SNAP-fusion protein to the potent monomethyl auristatin-F (BG-AURIF). Results: The L49(scFv)-SNAP-Alexa488 conjugate demonstrated specific binding and internalization into MTf-positive melanoma and TNBC cells. The corresponding ADC, L49(scFv)-SNAP-Linker-AURIF, exerted potent, antigen and dose-dependent cytotoxicity, with IC₅₀ values in the nanomolar range (4.77–34.43 nM). Conclusions: We successfully generated a novel SNAP-tag-based ADC that selectively eliminates MTf-overexpressing tumor cells. This proof-of-concept highlights MTF’s value as a therapeutic target and demonstrates that a smaller-format, non-cleavable linker SNAP-tag-based ADC can achieve potent nanomolar cytotoxicity, supporting further development of MTF-targeted immunotherapies for melanoma and TNBC. Full article