Govindarajan, Rang

Background Pancreatic ductal adenocarcinoma (PDAC), the most common malignant type of pancreatic cancer, is characterized by a dense desmoplastic stroma, low neoantigen burden, and a highly immunosuppressive tumor microenvironment (TME). Methods We present a novel strategy harnessing acute transplant rejection mechanisms by employing a recombinant oncolytic rVMG vector engineered to express murine alloantigens H-2Kb (rVMG-H-2Kb) or H-2Kk (rVMG-H-2Kk), thereby inducing tumor-specific antigenic mismatch responses. Results In vitro, rVMG-H-2Kb and rVMG-H-2Kk exhibited strong replication and cytolytic activity while inducing cell surface expression of both H-2Kk and endogenous H-2Kb, in addition to upregulation of antigen presentation genes (β2-microglobulin, Tap1, and Tapbp). In two immunocompetent PDAC models, intratumoral and systemic delivery of rVMG-H-2Kb and rVMG-H-2Kk delayed tumor progression, with rVMG-H-2Kk conferring a survival advantage. Multiplex immunohistochemistry and immunophenotyping revealed substantial TME remodeling, marked by increased effector T-cell infiltration, regulatory T-cell depletion, and reduced fibrosis. Spatial transcriptomics further showed compartment-specific immune activation and epithelial metabolic reprogramming, corroborating with enhanced tumor immunogenicity. Despite these effects, rVMG-H-2Kk also induced compensatory immunosuppressive pathways, including upregulation of antiviral response genes and immune checkpoint receptors such as programmed death-ligand-2. Importantly, combination therapy with rVMG-H-2Kk and murine checkpoint blockade (anti-programmed cell death protein-1 and anti-cytotoxic T-lymphocyte-associated protein 4) drastically improved survival compared to checkpoint blockade alone. Strikingly, surviving mice resisted tumor rechallenge, indicating the establishment of durable antitumor memory. Conclusion These findings establish rVMG-mediated alloantigen delivery as a novel immunotherapeutic platform capable of converting immune-cold tumors into immune-hot, sensitizing tumors to immune checkpoint inhibitors, and establishing durable antitumor immunity in PDAC.

PURPOSE The primary objective of this randomized, double-blind, placebo-controlled, multicenter phase II study (Alliance A221805) was to screen two doses of duloxetine for preventing sensory oxaliplatin-induced peripheral neuropathy (OIPN). METHODS Participants were randomly assigned 1:1:1 to receive once daily 30 mg duloxetine, 60 mg duloxetine, or placebo. Eligible participants had stage II to III colorectal cancer and no baseline neuropathy, had Eastern Cooperative Oncology Group performance status 0-2, were age 25 years and older, and received oxaliplatin via one of the following doses and schedules: 85 mg/m 2 every 2 weeks (6 or 12 doses) or 130 mg/m 2 every 3 weeks (4 doses). Duloxetine/placebo was taken once daily beginning day 1 of cycle 1 and continued for 17 weeks. The primary end point, a composite response reflecting sensory OIPN symptom severity and onset, was measured in weeks 19-21 using a validated participant-reported outcome survey assessing extremity numbness, tingling, and pain. Response was defined as a participant-reported highest score of ≤2 (ie, 1 = not at all; 2 = a little) on survey items. To be evaluable for the response end point, eligible participants must have initiated oxaliplatin and submitted ≥1 postbaseline OIPN survey. RESULTS Of the 199 participants (n = 66, 30 mg duloxetine; n = 66, 60 mg duloxetine; n = 67, placebo), 46, 47, and 50 (N = 143, 71.8%), respectively, were evaluable for primary end point analysis based on modified intention-to-treat criteria. Participant mean age was 55.1 years (standard deviation = 10.4). Most were White (n = 113, 80.7%) and male (n = 82, 58.6%). The proportion of responders among those receiving placebo (68.0%) was similar to those receiving duloxetine 30 mg (65.2%) or 60 mg (66.0%). Duloxetine adherence rates, measured via pill counts—30 mg (54%), 60 mg (57%), and placebo (59%) groups—were low (<75%). CONCLUSION Duloxetine is not more promising than placebo for preventing sensory OIPN.

Abstract: Primary cutaneous sweat gland carcinomas (SGCs) are rare tumors that commonly involve axillae, have a high local recurrence rate, and rarely show sarcomatoid transformation. A 68-year-old man presented with rapid enlargement of a previously stable, asymptomatic pea-sized nodule in the left axilla. Initial excision (with positive surgical margins) at another institution showed characteristic histologic features of a high-grade osteosarcoma and molecular analysis using a 92-gene real-time quantitative reverse transcription–polymerase chain reaction assay confirmed a diagnosis of osteosarcoma with 96% certainty. Notably, the molecular assay demonstrated consistently high relative expression of pannexin 3 (PANX3), a gene involved in normal osteoblast differentiation which, when highly expressed, strongly predicts osteosarcoma per the assay's algorithm. However, on further histologic review, the tumor also contained focal cystic areas, nests, and ducts composed of malignant epithelial cells reminiscent of SGC; these areas directly transitioned into the osteosarcomatous component and were strongly positive for pancytokeratin, CK7, and p63. Within 2 weeks, the lesion recurred and grew rapidly, prompting complete resection, histologic sections of which showed high-grade osteosarcoma without residual epithelial elements. This is the fifth report, to our knowledge, of osteosarcomatous transformation in a SGC, and the only report to date including molecular data. This case demonstrates that osteosarcoma arising from a SGC has a similar molecular profile to de novo primary osteosarcoma of bone. It also emphasizes the importance of histopathologic findings as the established diagnostic gold standard and the need to interpret molecular results within the clinical context.