Ras signaling plays an essential role in immune cell function; however, its activity must be precisely controlled to prevent excessive activation and associated cellular dysfunction. In this study, we identify the leukocyte-specific Ras GTPase-activating protein (RasGAP) RASAL3 as an important regulator of CD8⁺ T cell homeostasis and anti-tumor immunity. Following T cell receptor (TCR) stimulation, RASAL3-deficient CD8⁺ T cells display sustained Ras activation, resulting in increased activation-induced cell death (AICD). The surviving RASAL3-deficient CD8⁺ T cells exhibit impaired effector functions, including reduced cytokine production and decreased tumor-killing activity. Using an in vivo B16-F10 melanoma model, we found that CD8⁺ T cell-specific RASAL3-deficient mice (R3^fl/flCd8-Cre) develop significantly faster tumor growth compared with control mice. Although Programmed death protein 1 (PD-1) blockade partially restores anti-tumor responses in these mice, the therapeutic effect remains markedly weaker than that observed in control animals. In human melanoma samples, RASAL3 expression is reduced in tumor-infiltrating CD8⁺ T cells. Furthermore, patients with metastatic melanoma show lower RASAL3 expression in primary tumors compared with patients without metastasis, and higher RASAL3 expression in CD8⁺ T cells within primary lesions is associated with improved overall survival. Together, these findings reveal that RASAL3 is required for the maintenance of CD8⁺ T cell survival and effector activity. Reduced RASAL3 expression may represent a mechanism by which tumors evade immune surveillance, and RASAL3 expression in CD8⁺ T cells may serve as a potential biomarker for predicting clinical outcomes in melanoma.

The oral mucosa is a microbe-exposed barrier ecosystem in which surface biofilms, epithelial differentiation programs, microbial products, metabolic stress, stromal remodeling, and immune surveillance are spatially organized. Although oral microbiome studies have associated dysbiosis with oral potentially malignant disorders (OPMDs) and oral squamous cell carcinoma (OSCC), most evidence remains saliva-based, rinse-based, swab-based, tissue-homogenate-based, or taxon-centered. These approaches can identify disease-associated microbial patterns but cannot determine whether microbial signals are locally aligned with epithelial, metabolic, stromal, and immune changes within the same mucosal microdomains. Here, we propose a spatial-microbial-metabolic-immune (SMMI) framework as an evidence-ranked and testable approach for studying malignant transformation risk in high-risk OPMDs. The acronym denotes four analytical dimensions-spatial organization, microbial signals, metabolic mediation, and immune remodeling-all interpreted within oral host tissue. The framework asks whether dysbiosis-associated microbial signals, epithelial barrier-response states, metabolic stress, stromal remodeling, macrophage-centered immunoregulation, altered epithelial immune visibility, and T-cell positioning become locally aligned within candidate mucosal microdomains. SMMI is a conceptual and validation framework rather than an established causal mechanism, fixed anatomical structure, or immediate therapeutic target. This article is an evidence-ranked conceptual review rather than a systematic review. We distinguish direct human OPMD evidence from OSCC-derived inference, preclinical perturbation data, broader cancer biology, methods papers, and speculative but testable hypotheses. We outline a modular validation roadmap that proceeds from pathology-anchored sampling and contamination-aware microbial localization to hypothesis-selected spatial modules, targeted functional testing, and longitudinal clinical validation. The near-term translational goal is improved risk stratification and risk-adapted surveillance, rather than ecological intervention. By reframing high-risk OPMDs as spatial oral microbe-host immune-metabolic ecosystems, the SMMI framework provides a cautious structure for hypothesis generation, spatial validation, and clinically relevant risk modeling.

Many spinal cord-injured (SCI) patients are recurrently catheterized to manage urinary retention and incontinence. Microbial pathogens colonize urethral catheter surfaces, persist in form of biofilms and trigger inflammatory responses in the bladder. Our objective was to determine bladder tissue changes due to long-term inflammation using LC-MS proteomics.

We examined longitudinal proteomic profiles from eight SCI patients, sampled over 2 to 6 months, in a patient-specific manner as well as compared with trauma patients diagnosed with acute urinary tract infections (UTI). The sample sources were urinary pellets (UP) from all subjects, and catheter biofilm extracts (CB) from SCI patients. Bioinformatic protein network and western blot analyses served to corroborate evidence of protein and cell differentiation changes in the urinary tract of SCI patients.

More than 50 proteins with functional or structural roles in the epidermal cornified envelope were quantitatively increased in proteomic profiles from three SCI patients. This included stress response keratins and proteins involved in keratin crosslinking, e.g. transglutaminases and small proline-rich proteins, suggesting occurrence of keratinizing squamous epithelial metaplasia. Protein co-expression network analyses supported epithelial trans-differentiation changes. Nearly thirty proteins with gastro-intestinal epithelial cell expression specificity were enriched in proteomic profiles from a single SCI patient. Among those were mucin-2 and sucrase-isomaltase, secreted proteins detected in samples for only that patient via western blots. This finding was consistent with intestinal epithelial metaplasia.

Without using invasive cystoscopy and histopathology, proteomic analyses from easily available UP and CB samples allowed us to infer cell differentiation changes in urothelial tissues of SCI patients with chronic infections, supporting a concept of clinical relevance for urothelial metaplasia screening, a precursor stage of urothelial neoplasms.

This work has innovative value and biological significance in discovering abnormal mucosal epithelial trans-differentiation processes. Knowledge of metaplasia in catheterized SCI patients with chronically infected and inflamed urinary tracts is also clinically relevant. Metaplasia signatures were discovered from differential LC-MS proteomic analyses of urinary pellet and bladder catheter biofilm extracts obtained in longitudinally studies, without use of invasive medical procedures (cystoscopy). Distinct protein clusters were indicative of either keratinizing squamous epithelial metaplasia or intestinal metaplasia in urothelial tissues. Chronic inflammation is a known trigger of epithelial trans-differentiation, but intestinal metaplasia in urethral and bladder tissue has rarely been reported.

DICER1 tumor predisposition syndrome is a rare autosomal-dominant disorder resulting from heterozygous germline pathogenic variants in DICER1, a critical regulator of microRNA biogenesis and RNA interference. The syndrome predisposes individuals to a broad spectrum of benign and malignant neoplasms, primarily affecting pediatric and young adult populations. Gynecologic manifestations are notably heterogeneous and include the well-established associations with embryonal rhabdomyosarcoma and Sertoli-Leydig cell tumor. DICER1 alterations have also been identified in gynandroblastoma, a subset of adenosarcomas, and emerging entities such as DICER1-related Wilms-like uterine tumor and, less consistently, in rare examples of juvenile and adult granulosa cell tumor, Sertoli cell tumor, germ cell tumors, and carcinosarcoma. Despite their diverse anatomic sites, some of these neoplasms share recurrent morphologic hallmarks, including primitive mesenchyme, fetal-type epithelium and cartilage, rhabdomyosarcomatous and neuroectodermal differentiation, and anaplasia. Recent evidence has broadened the morphologic, molecular, and clinical understanding of DICER1-associated neoplasms. Recognition of these distinctive morphologic features is essential for prompting timely testing for DICER1 alterations and facilitating appropriate genetic counseling, surveillance, and early detection strategies for patients and their families. This review synthesizes current knowledge with emerging insights to enhance the diagnostic recognition of these rare yet clinically significant entities.

Not available.

Genomic instability manifests in two distinct ways based on DNA alteration scale, differentially affecting the tumor-immune microenvironment. Mutational instability involves excessive accumulation of small-scale alterations, such as substitutions and indels, from defective DNA repair or aberrant mutagenic processes, generating neoantigens and increased immunogenicity. Chromosomal instability encompasses large-scale alterations in which cells gain, lose, or rearrange chromosomes, resulting in aneuploidy and immune evasion through chronic innate activation and myeloid remodeling. This review outlines differences between mutational and chromosomal instability and discuss how their interplay shapes tumor immunogenicity and response to immunotherapy. Understanding these opposing mechanisms could inform immunotherapeutic approaches in cancer.

Mutational and chromosomal alterations exert opposing effects on antitumor immunity. Hypermutated tumors can generate abundant neoantigens that prime adaptive immunity and sensitize tumors to checkpoint blockade. In contrast, chromosomal instability triggers chronic innate immune signaling that is paradoxically immunosuppressive, in part through myeloid cell and T-cell dysfunction. Integrating both processes into a unified framework could help uncover mechanisms of immune evasion and guide personalized immunotherapeutic strategies.

To describe the clinical presentation, radiological findings, and surgical management of intracranial metastasis from medullary thyroid carcinoma, an exceedingly rare occurrence not previously reported in Pakistan.

This case series describes three patients who presented to the neurosurgery outpatient clinic at Dow University Hospital, Karachi, in November 2024, June 2025, and January 2026 respectively, with scalp swellings and persistent headaches unresponsive to analgesics. Two patients also had seizures. Contrast-enhanced MRI in each case demonstrated an enhancing lesion extending from the intracranial compartment through the skull into the scalp, initially raising suspicion of an aggressive or invasive meningioma. All three underwent craniectomy with gross excision of the lesion, duraplasty, and cranioplasty, with tissue sent for histopathological analysis.

Histopathology in all three cases confirmed metastatic medullary thyroid carcinoma rather than meningioma. Postoperative recovery was uneventful, with resolution of headaches and seizures. On follow-up, patients remained clinically stable with no recurrence of symptoms.

Medullary thyroid carcinoma can metastasize to the brain and mimic primary CNS tumours such as meningioma on imaging, despite this being rare. A high index of suspicion and thorough metastatic workup are warranted whenever an intracranial lesion is encountered, and whole-body screening should be considered whenever a primary malignancy is identified, regardless of how uncommon its metastatic spread may be.

A case of recurrent anaplastic oligodendroglioma treated with carboplatin and etoposide as fourth-line chemotherapy is presented. The efficacy of carboplatin and etoposide is highlighted as a salvage regimen and the risk of therapy-related acute myeloid leukaemia (t-AML) as a long-term complication of prolonged alkylating agent exposure.

The case report is of a 44-year-old female who initially presented in 2020 with seizures and headache. Imaging revealed a frontal lobe lesion, for which she underwent craniotomy with resection; histopathology confirmed anaplastic oligodendroglioma. Following residual disease on post-operative imaging, she received concurrent chemoradiotherapy (CCRT) with temozolomide (TMZ), followed by maintenance TMZ. On disease progression, she was sequentially treated with three further lines of therapy: bevacizumab/irinotecan, then PCV (procarbazine, lomustine, vincristine), and subsequently carboplatin and etoposide, initiated in April 2022 as fourthline therapy, continued for a total of 40 cycles. Clinical and radiological response, as well as treatment-related toxicity, were assessed throughout the course of therapy.

The patient achieved an excellent response to fourth-line carboplatin and etoposide, with a survival benefit of approximately 40 months on this regimen. Despite this favourable disease control, she subsequently developed therapy-related acute myeloid leukaemia (t-AML), a rare but recognized complication of prolonged alkylating agent exposure, and ultimately succumbed to this secondary malignancy.

Carboplatin and etoposide may be considered a viable salvage treatment option for heavily pretreated patients with recurrent oligodendroglioma who have progressed through multiple prior lines of therapy, offering meaningful survival benefit even in the fourth-line setting. However, this case underscores the importance of vigilant long-term monitoring for serious late toxicities, particularly Acute Myeloid Leukaemia.

Glioblastoma (GBM), IDH-wildtype WHO Grade IV, is the most aggressive primary brain tumour. Although temozolomide (TMZ) remains standard-of-care, ~50% develop resistance driven by cytoprotective autophagy. GORASP2, an autophagy regulator linked to hyperactivated mTOR signaling in GBM, remains largely unexplored. This study characterized the molecular significance of GORASP2 across independent Western and Eastern cohorts using an integrative multi-database approach..

This in silico study used GEPIA2 (TCGA, n=163; GTEx, n=207) and CGGA cohorts (mRNAseq_693, n=672; mRNAseq_325, n=329) for expression/prognosis; cBioPortal (n=592, 611) for genomic alterations; and UALCAN/CPTAC (normal, n=10; tumour, n=99) for protein expression. Co-expression, immune infiltration, singlecell, and pathway analyses used GEPIA2/CGGA, TIMER3.0, TISCH2, and STRING/GO, with significance via ANOVA, ttests, log-rank tests, and Pearson correlation (p<0.05).

GORASP2 mRNA and protein were overexpressed in GBM versus normal brain (p<0.05), elevated further in mTOR-altered tumours (p=0.0109). Expression rose with WHO grade in mRNAseq_325 (p=0.00018) but not mRNAseq_693 (p=0.52), with no difference between primary and recurrent GBM. GORASP2 was non-prognostic for survival, but showed strong correlation with Golgi-trafficking (RAB1A, RAB2A, GOLPH3) and autophagy-initiation genes (BECN1, UVRAG, STX17), and moderate-to-strong correlation with mTOR genes (MTOR, RPTOR, RICTOR); late autophagy markers (MAP1LC3B, LAMP2, SQSTM1) strengthened only in recurrent GBM. Immune profiling showed positive correlation with cytotoxic T-cells, negative with macrophages. GORASP2 was minimal in T-lymphocytes but enriched in malignant cells, found highest cell line expression of GBM in T98G/DK-MG and moderate in U-87MG/U- 251MG (nTPM ~58-90). GO enrichment highlighted Golgi vesicle transport and autophagosome assembly; STRING placed GORASP2 within a 29-gene network.

Integrative cross-population multi-database analysis reveals an association between GORASP2 and autophagy-related pathways in glioblastoma. Although GORASP2 does not independently prognostic biomarker. GORASP2's consistent association with Golgi-trafficking, autophagy, and mTOR signaling supports its prioritization for in vitro validation and evaluation as a therapeutic target in TMZ-resistant glioblastoma.

The RCT was registered retrospectively at the Pan African Clinical Trials Registry (PACTR) (Trial #: PACTR202301506140749 Date of Approval: 06/01/2023). Link: https://pactr.samrc.ac.za/Search.aspx.

Citrate anticoagulation during therapeutic plasma exchange (TPE) chelates divalent cations and can precipitate torsades de pointes (TdP) in patients with pre-existing repolarization vulnerability. We report a 44-year-old woman with genetically determined long QT syndrome Type 2 (LQT2) presenting in myasthenic crisis due to anti-MuSK-positive myasthenia gravis. TPE was initiated urgently before confirmatory antibody results were available, as alternative rapid immunomodulatory options were not immediately accessible. Despite prophylactic electrolyte supplementation, the corrected QT interval (QTc) progressively prolonged, rising from a baseline of 493 to 509 ms-exceeding the 500 ms high-risk threshold-immediately before TdP onset during the second TPE. TPE was discontinued and replaced with double-filtration plasmapheresis (DFPP) using albumin-based replacement, which reduces citrate exposure by retaining the patient's own albumin. Five subsequent DFPP sessions were completed without arrhythmia recurrence. This case highlights the apheresis-related arrhythmia risk in LQT2 and the mechanistic rationale for DFPP as a safer alternative.