Polypyrimidine tract-binding protein 1, an alternative splicing factor, drives cancer-associated metabolic reprogramming by modulating pyruvate kinase M splicing. Although organ-abundant microRNAs (miRs) regulate this protein, its role in tumor progression remains unclear. Therefore, we investigated the functional relationship between polypyrimidine tract-binding protein 1-associated microRNAs and this protein in pancreatic cancer to identify pancreas-enriched microRNAs and explore polypyrimidine tract-binding protein 1 function beyond metabolic regulation. The expression of miR-216b-5p, which is typically pancreas-enriched, was significantly downregulated in clinical pancreatic cancer samples, whereas polypyrimidine tract-binding protein 1 expression was markedly upregulated. Mechanistically, miR-216b-5p directly binds to the 3' UTR of polypyrimidine tract-binding protein 1 mRNA, thereby suppressing its expression and inhibiting cancer cell proliferation. Proteomic analysis, integrated with publicly available individual-nucleotide resolution UV crosslinking and immunoprecipitation data, identified thymidylate synthase as a novel downstream target of polypyrimidine tract-binding protein 1, likely regulated via splicing-related RNA-level mechanisms. Thymidylate synthase expression was also elevated in pancreatic cancer tissues and correlated with poor prognosis. Functional assays revealed that polypyrimidine tract-binding protein 1 and thymidylate synthase silencing induced cell cycle arrest. Our findings uncover a previously unrecognized miR-216b-5p/polypyrimidine tract-binding protein 1/thymidylate synthase regulatory axis that promotes pancreatic cancer progression and establish polypyrimidine tract-binding protein 1 as a central molecular regulator of tumor biology beyond its metabolic role.

In 2016, the Japan Children's Cancer Group launched a nationwide research initiative to provide central diagnosis incorporating pathology review and molecular profiling for pediatric central nervous system (CNS) tumors. Over the first eight years, 2224 cases were registered. Non-next-generation sequencing analyzes, such as pyrosequencing and NanoString, were routinely performed, mainly for glioma, medulloblastoma, and ependymoma. Additional analyzes, including methylation profiling and RNA sequencing, were conducted for selected diagnostically challenging cases. The most common diagnoses were low-grade glioma (26%), medulloblastoma (18%), germ cell tumor (16%), high-grade glioma (12%), and ependymoma (11%). Diagnostic or targetable alterations were detected in nearly half of the glioma samples. Among medulloblastomas, Group 4 was the most prevalent subgroup (48%), followed by SHH-activated (28%), Group 3 (14%), and WNT-activated (11%). Among ependymomas, 95% of posterior fossa ependymomas were classified as PFA, and 72% of supratentorial ependymomas were positive for ZFTA fusion. Methylation-based classification enabled diagnostic refinement and identification of recently recognized novel subtypes. The integration of histopathological review by central pathologists and detailed molecular analyzes facilitated the recognition of rare tumors not yet defined in the World Health Organization classification. Our experience underscores the value of integrated diagnosis, which is now regarded as standard practice for pediatric CNS tumors, and highlights the urgent need for a sustainable clinical framework that incorporates molecular testing. This report represents the first comprehensive overview of the pediatric CNS tumor landscape in Japan in the molecular era.

Fangji Huangqi Decoction (FJHQ), a traditional Chinese medicine formula derived from "Jin Gui Yao Lue," has been reported to exhibit immunomodulatory and anti-inflammatory effects. This study investigates its potential anti-tumor mechanism via the enhancement of CD8+ T cell-mediated immunity. In murine B16 melanoma and Lewis lung carcinoma models, FJHQ significantly suppressed tumor growth and enhanced CD8+ T cell infiltration and cytotoxicity. CD8+ T cell depletion abrogated these effects, confirming their necessity. Invitro, FJHQ treatment augmented antigen presentation by tumor cells through upregulation of MHC-I expression, leading to improved CD8+ T cell recognition and killing. Mechanistically, FJHQ inhibited autophagic flux in tumor cells, as evidenced by mCherry-GFP-LC3 reporter assays and electron microscopy, resulting in impaired lysosomal function and elevated MHC-I levels. Furthermore, combining FJHQ with anti-PD-1 therapy synergistically promoted CD8+ T cell activity, increased granzyme B and IFN-γ expression, and induced substantial tumor regression. These findings demonstrate that FJHQ enhances antitumor immunity by suppressing autophagy and elevating MHC-I expression, thereby sensitizing tumors to PD-1 blockade. FJHQ represents a promising immunoadjuvant for cancer therapy.

In colon cancer (CC), the polarization of tumor-associated macrophages (TAMs) toward the M2 phenotype plays a critical role in immune therapy resistance, yet the underlying metabolic "switch" has not been fully elucidated. While the function of stearoyl-CoA desaturase 1 (Scd1) in tumor cells has been reported, its role in TAMs remains unknown. We generated Lyz2-Cre-driven myeloid-specific Scd1 knockout (Scd1 cKO) mice and wild-type (Scd1 WT) control mice. Both groups were subcutaneously injected with MC38 cells to establish a colon cancer model. Flow cytometry was utilized to assess the polarization status of TAMs and the infiltration of CD8+ T cells in tumor tissues. RNA sequencing (RNA-seq) combined with Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was performed to identify differentially expressed genes and key signaling pathways. RT-qPCR and Western blot analysis were used to examine the expression of core molecules within these pathways. Scd1 cKO mice exhibited faster tumor growth and increased tumor weight compared to Scd1 WT mice. Scd1 deletion enhanced TAM polarization toward the M2 phenotype and suppressed the Hippo-YAP pathway, leading to CD8+ T cell exhaustion. Furthermore, TT-10 treatment reversed M2 polarization, restored CD8+ T cell infiltration and effector function, and slowed tumor progression. In conclusion, Scd1 knockout in macrophages accelerates colon cancer by promoting M2 polarization via inhibition of the Hippo-YAP pathway, impairing CD8+ T cell function. Targeting the Scd1-Hippo-YAP signaling axis may offer a promising new approach for immunotherapy in colon cancer.

Alternative splicing plays a crucial role in the development and progression of hepatocellular carcinoma (HCC), yet the underlying regulatory mechanisms and therapeutic potential remain largely unexplored. Here, we identified the RNA-binding protein FMR1 autosomal homolog 1 (FXR1) as a key driver of HCC pathogenesis through the regulation of alternative splicing. FXR1 was highly expressed in HCC tissues, and its elevated expression was associated with a poor prognosis. Mechanistically, high FXR1 induced the retention of exon 6 in mitogen-activated protein kinase-activated protein kinase 5 (MK5), generating a long, kinase-competent isoform (termed MK5-L). This isoform acted as an important oncogenic factor for HCC progression by phosphorylating GSK3β and subsequently activating the Wnt/β-catenin pathway. Functional studies showed that the FXR1/MK5-L axis is critical for HCC cell proliferation and metastasis, both invivo and invitro. Importantly, therapeutic intervention using an FXR1-targeting antisense oligonucleotide (ASO) effectively suppresses tumor progression and metastasis in preclinical models by shifting splicing toward the inactive MK5-S isoform. Overall, our study unveils a novel splicing-mediated oncogenic pathway and establishes FXR1 and its downstream target MK5-L as promising prognostic biomarkers and therapeutic targets for HCC.

Protein phosphorylation is a central post-translational modification regulating cellular signaling, frequently dysregulated in cancer. Mass spectrometry (MS)-based phosphoproteomics has emerged as a powerful approach to systematically profile phosphorylation events, thereby revealing aberrant kinase activity and therapeutic vulnerabilities that are not captured by genomic or transcriptomic analyses. Recent advances across the workflow-including optimized sample preparation and phosphopeptide enrichment, isotope- or label-free quantitative strategies, high-resolution mass spectrometry platforms, specialized algorithms for site identification and quantification, and integrative informatics analyses-have enabled the detection of tens of thousands of phosphorylation sites even from small clinical specimens. These developments have facilitated the characterization of signaling pathways across diverse cancer types, leading to the identification of targetable kinases and informing therapeutic strategies. In this review, we highlight studies that employed phosphoproteomic analyses of clinical specimens or patient-derived cancer cells to delineate signaling characteristics and to propose and validate therapeutic targets. Collectively, MS-based phosphoproteomics is poised to become a cornerstone of precision oncology. By enabling comprehensive and quantitative mapping of phosphorylation events, this technology allows mechanistic dissection of cancer signaling pathways and uncovers therapeutic vulnerabilities that may be exploited with targeted agents.

HER2-positive gastric cancer represents a distinct molecular subtype characterized by chromosomal instability, variable HER2 amplification, and substantial intratumoral heterogeneity. Although HER2-targeted therapies have improved clinical outcomes, therapeutic resistance commonly develops and limits long-term benefit. Established resistance mechanisms include bypass signaling through alternative receptor tyrosine kinases, reactivation of downstream pathways such as PI3K-AKT and MAPK, and dynamic changes in HER2 expression during treatment. These findings underscore the complexity of signaling regulation in HER2-driven tumors and indicate that mechanisms beyond receptor-level inhibition contribute to persistent oncogenic signaling. In this review, we examine the concept of transcriptional reinforcement within the HER2-RAS signaling network and discuss RUNX-dependent regulation of SOS1 as a downstream mechanism that may sustain signaling activity. We position this regulatory axis within the broader landscape of established resistance mechanisms and emerging therapeutic strategies, including antibody-drug conjugates, kinase inhibitors, and rational combination approaches. By integrating canonical resistance pathways with transcriptional regulation, this review provides a balanced perspective on how downstream regulatory processes may influence therapeutic response in HER2-positive gastric cancer.

Ovarian cancer is one of the most prevalent gynecologic malignancies worldwide. Dysregulated cell proliferation and angiogenesis are well-recognized to be involved in the pathogenesis of ovarian cancer. Nucleolar Protein 7 (NOL7), a novel RNA-binding protein, has been identified as a tumor suppressor and a key anti-angiogenetic factor. However, the function of NOL7 and its underlying molecular mechanisms in ovarian cancer remain unclear. In this study, we demonstrated that NOL7 expression was down-regulated in ovarian cancer tissues, and low NOL7 expression was associated with poorer prognosis in patients with ovarian cancer. Overexpression of NOL7 decreased cell viability, inhibited cell cycle entry and proliferation, and promoted apoptosis in OVCAR-3 and SKOV-3 cells. Additionally, NOL7 overexpression decreased VEGF-A level, increased TSP-1, and suppressed angiogenesis of human umbilical vein endothelial cells (HUVECs). Conversely, knockdown of NOL7 in ovarian cancer cells enhanced cell proliferation and angiogenesis, while reducing apoptosis. Invivo experiments further confirmed that NOL7 overexpression inhibited tumor growth and angiogenesis. Mechanistic studies revealed that NOL7 could bind to the 3'UTR of growth arrest and DNA damage inducible alpha (GADD45A), and overexpression of NOL7 up-regulated GADD45A expression by stabilizing GADD45A mRNA in ovarian cancer cells. The anti-cancer effects of the NOL7/GADD45A were mediated by inhibiting the phosphorylation of STAT3 at Ser727. Collectively, our findings indicate that NOL7 functions as a tumor suppressor in ovarian cancer and provide a novel therapeutic target for the treatment of ovarian cancer.

Endometrial cancer, the most common gynecological malignancy with an annual increase of 1%-3%, lacks suitable noninvasive diagnostic tools, as current methods like hysteroscopy and biopsy are invasive and impractical for routine screening. We conducted a comprehensive, multilayered marker discovery workflow integrating whole-genome bisulfite sequencing and targeted methylation panels in tumor and control tissues, then prioritized and optimized candidates for detection in cervical exfoliated cells. Using a two-stage design, we built and tested a quantitative methylation-specific PCR (qMSP) model in ThinPrep Cytology Test (TCT) samples, with 148 samples for discovery/model construction and an independent cohort of 80 TCT samples for validation. We identified a three-gene methylation panel-ZNF626, GRIA4, and SPDYA-that demonstrated high accuracy for early endometrial cancer detection from cervical cytology. In the validation cohort, the model showed strong performance across menopausal subgroups: in premenopausal women, sensitivity was 90.91% and specificity for benign endometrial disease was 92.59%; in postmenopausal women, sensitivity and specificity were 96.55% and 84.62%, respectively. Notably, the approach achieved a 92.86% detection rate for stage I endometrial cancer. These results support a robust, noninvasive diagnostic strategy that leverages simple cervical cytology sampling to enable early detection, facilitate clinical decision-making, and potentially improve outcomes for patients at risk of endometrial cancer.