UNASSIGNED: The impact of stroma-targeting therapy on tumor immune suppression is largely unexplored. An RNA oligonucleotide, STNM01, has been shown to repress carbohydrate sulfotransferase 15 (CHST15) responsible for tumor proteoglycan synthesis and matrix remodeling. This phase I/IIa study aimed to evaluate the safety and efficacy of STNM01 in patients with unresectable pancreatic ductal adenocarcinoma (PDAC).
UNASSIGNED: This was an open-label, dose-escalation study of STNM01 as second-line therapy in gemcitabine plus nab-paclitaxel-refractory PDAC. A cycle comprised three 2-weekly endoscopic ultrasound-guided locoregional injections of STNM01 at doses of 250, 1,000, 2,500, or 10,000 nM in combination with S-1 (80-120 mg twice a day for 14 days every 3 weeks). The primary outcome was the incidence of dose-liming toxicity (DLT). The secondary outcomes included overall survival (OS), tumor response, changes in tumor microenvironment on immunohistopathology, and safety (jRCT2031190055).
UNASSIGNED: A total of 22 patients were enrolled, and 3 cycles were repeated at maximum; no DLT was observed. The median OS was 7.8 months. The disease control rate was 77.3%; 1 patient showed complete disappearance of visible lesions in the pancreas and tumor-draining lymph nodes. Higher tumoral CHST15 expression was associated with poor CD3+ and CD8+ T cell infiltration at baseline. STNM01 led to a significant reduction in CHST15, and increased tumor-infiltrating CD3+ and CD8+ T cells in combination with S-1 at the end of cycle 1. Higher fold increase in CD3+ T cells correlated with longer OS. There were 8 grade 3 adverse events.
UNASSIGNED: Locoregional injection of STNM01 was well tolerated in patients with unresectable PDAC as combined second-line therapy. It prolonged survival by enhancing T cell infiltration in tumor microenvironment.
UNASSIGNED: The present study was supported by the Japan Agency for Medical Research and Development (AMED).

UNASSIGNED: Retroperitoneal liposarcoma (RPLS) is a rare, biologically heterogeneous tumor with distinct clinical characteristics, such as frequent local recurrence, repeated relapse, and rare distant metastasis. No effective targeted therapy is available for RPLS. Here, we aim to determine the pathological functions and therapeutic potential of carbohydrate sulfotransferase 15 (CHST15) in RPLS.
UNASSIGNED: Tumor-derived mesenchymal progenitor cells (MPCs) and normal adipose derived mesenchymal stem cells (MSCs) were obtained from patients with RPLS. MPCs and MSCs were isolated and characterized based on surface markers, proliferation, and differentiation using flow cytometry and molecular staining. Transcriptome analysis was performed to decipher expression profile of differentiation-related genes in 3 paired MSCs and MPCs. Further confirmation of genes were performed using quantitative real-time polymerase chain reaction (qRT-PCR). Plasmids overexpressing CHST15 were transfected into adipose MSCs to examine fibrosis-related gene expression at mRNA level by real-time PCR.
UNASSIGNED: The tumor stromal-derived MPCs expressed CD105, CD73, and CD90, and exhibited osteogenic and adipogenic differentiation potential in vitro. The proliferation of tumor-derived MPCs was significantly lower than that of normal adipose-derived MSCs (P<0.001). Transcriptome analysis revealed upregulation of IL-7R, ALPL, PKNOX2, and CHST15 in tumor-derived MPCs. CHST15 was highly expressed in tumor-derived MPCs (P<0.001). CHST15 mediated fibrosis-related FGF2 gene expression in MSCs (P<0.05) and MPCs (P<0.001).
UNASSIGNED: CHST15 is upregulated in tumor-derived MPCs and regulates fibrosis in RPLS. This provides clues for development of novel therapeutic strategies by targeting CHST15-induced MPC activation in RPLS.

Fibrosis continues to be paid a great attention in not only basic research but also clinical practice, especially for the development of novel therapeutics in various fibrotic diseases. However, there remain several obstacles to translation in developing anti-fibrosis therapy. The present review documents our translational practice from target discovery to first-in-patient studies in the development of anti-fibrosis therapy for inflammatory bowel disease (IBD). First topic is a target selection. We have focused on the target that has an ability to regulate multifactorial cascades of fibrosis. Carbohydrate sulfotransferase 15 (CHST15) synthesizes matrix proteoglycan that regulates various pathogenic mediators and contributes to tissue remodeling during injury. Small interfering RNA (siRNA) targeting CHST15 inhibited activation of fibroblasts in vitro and reduced fibrosis in vivo. Second topic is a clinically feasible application. We established a safe and novel pancolonic delivery of siRNA, which is achieved by direct injection to extracellular matrix (ECM) through endoscope. Third topic is an endpoint for both nonclinical and clinical studies. We have focused on tissue-specific findings for co-existence of fibrosis in ulcerative lesions in IBD and investigated whether the balance of mucosal healing (MH) and fibrosis, which is evaluated by endoscopy and histology respectively, can be used for study endpoints. Phase 1 clinical trial of STNM01, a synthesized CHST15 siRNA, by a single dose endoscopic submucosal injection for non-healer patients with Crohn\'s disease showed high rates of MH. Analyses of biopsy specimens revealed that STNM01 reduced CHST15 expression at local lesions, repressed pre-existing fibrosis and repaired the damaged crypts. Thus, blockade of multifactorial modulator CHST15 in ECM showed a potential to treat tissue remodeling and skew fibrosis toward mucosal repair. Our practice suggests that target- and tissue-specific findings-based strategy would be a key to translation in developing anti-fibrosis therapy.