Cancer Science最新文献

Amivantamab is a bispecific antibody against epidermal growth factor receptor (EGFR) and MET that has been approved for nonsmall cell lung cancer (NSCLC) with EGFR exon 20 insertion mutations and common EGFR mutations, such as exon 19 deletion and L858R. MET has attracted attention as a therapeutic target for lung cancer; however, its role in EGFR binding and amivantamab-induced antibody-dependent cellular toxicity (ADCC) remains unclear. We used high-speed atomic force microscopy (HS-AFM) to observe the real-time binding of amivantamab to the EGFR-extracellular domain (ECD) and MET-ECD and visualized the binding of amivantamab to the EGFR domain 3 and MET Sema domain. Furthermore, we observed the trimer comprising amivantamab bound to EGFR and MET. Western blot analysis of the gel filtration fractions revealed that the MET-ECD enhanced the binding of amivantamab to the EGFR-ECD, which promoted trimer formation. Moreover, amivantamab-induced mononuclear cell-mediated ADCC in NSCLC cells with common EGFR mutations. ADCC activity was positively correlated with EGFR expression in tumor cells. Studies using MET-knockout NSCLC cells revealed that MET enhanced ADCC activity with low concentrations of amivantamab. Thus, MET augments amivantamab binding to EGFR and augments ADCC activity at low amivantamab concentrations. These results indicate that binding to MET contributes to the increased efficacy of amivantamab in NSCLC with common EGFR mutations.

The clinical significance and molecular mechanisms underlying tumor progression in thymic epithelial tumors (TETs) remain largely unclear. In this retrospective single-center study, we evaluated the prognostic value of transforming growth factor-beta 1 (TGF-β1) and its relationship with programmed death-ligand 1 (PD-L1) expression. A total of 92 patients with surgically resected TETs, including 79 thymomas and 13 thymic carcinomas, were included. Immunohistochemical analyses were performed to assess the expression of TGF-β1, PD-L1, phosphorylated Smad2 (pSmad2), and pSmad3. Associations between TGF-β1 expression and clinicopathological features were analyzed, and mechanistic interactions were investigated using two thymic carcinoma cell lines exposed to exogenous TGF-β1. High TGF-β1 expression was observed in 28% of patients and was significantly associated with advanced Masaoka stage (III/IV), shorter tumor doubling time (median 328 vs. 713 days, p = 0.042), and lower 5-year freedom from recurrence (FFR) rates (58.1% vs. 95.1%, p < 0.001, log-rank test). Coexpression of high TGF-β1 and PD-L1 was linked to the poorest prognosis (5-year FFR: 46.1%) and was identified as an independent predictor of recurrence (adjusted hazard ratio: 7.15; 95% confidence interval: 1.20-42.8). Immunohistochemically, TGF-β1 expression positively correlated with PD-L1 and pSmad2/3 expression. In vitro, TGF-β1 stimulation upregulated PD-L1 expression in a dose-dependent manner, accompanied by increased pSmad2/3 activation. These findings indicate that high TGF-β1 expression demarcates a biologically aggressive TET phenotype and, together with PD-L1, refines postoperative risk stratification, while its ability to drive PD-L1 via Smad signaling could support the blockade of these pathways as a potential therapeutic strategy.

Wnt/β-catenin pathway, which is under the control of T cell factor/lymphocyte enhancer factor (TCF/LEF) transcription factors, plays a pivotal role during carcinogenesis through the regulation of cancer cell proliferation and differentiation. Thus, it is likely that an inhibitor against this pro-oncogenic pathway might be a promising anti-cancer drug candidate. In the present study, we have synthesized a novel polyamide (WNT-Chb) composed of N-methylpyrrole, N-methylimidazole, and DNA alkylator chlorambucil, and examined its anti-cancer effect on colon cancer cells in vitro and in vivo. Based on our results, WNT-Chb preferentially bound to a consensus TCF/LEF-responsive element (5'-CCTTTGA-3'), and suppressed multiple Wnt-target gene expression. Consistent with these results, WNT-Chb attenuated in vitro proliferation and in vivo tumor growth of colon cancer cells with an aberrantly activated Wnt/β-catenin pathway. Together, these findings strongly suggest that the originally produced WNT-Chb might be a novel anti-cancer drug candidate against Wnt/β-catenin pathway-dependent colon cancers.

Hepatocellular carcinoma (HCC) ranks among the most pervasive forms of cancer worldwide. In our study, we observed a notable overexpression of SNAPIN in human HCC tissues, which was linked closely to patient prognosis. Our experiments demonstrated that SNAPIN enhances the proliferative capacity of HCC cells. The knockdown of SNAPIN induces ferroptosis in HCC cells, whereas its overexpression partially resists the effects of ferroptosis inducers. As suggested by the above experimental findings, SNAPIN facilitates HCC progression by hindering HCC cell ferroptosis. Mechanistically, SNAPIN directly binds to KEAP1, facilitating its degradation via the autophago-lysosomal pathway, thereby undermining its stability. Consequently, NRF2 and its downstream target gene, GPX4, are upregulated. These alterations effectively mitigate lipid peroxidation damage, and ultimately impede HCC cell ferroptosis, potentially aiding in the progression of HCC. In conclusion, SNAPIN can negatively regulate the stability of KEAP1 protein, thereby initiating the NRF2/GPX4 pathway to hinder ferroptosis in HCC cells, ultimately facilitating HCC progression. Our results substantiate the pivotal function of SNAPIN in promoting HCC development, and this discovery is expected to provide an innovative therapeutic target for clinically managing HCC.

Improved peptide pharmacokinetics are needed to enhance the therapeutic effects of peptide-based radionuclide therapy. Conjugation of albumin binders, such as fatty acids, to tumor-targeting peptides slows blood clearance, resulting in higher tumor uptake. In this study, we synthesized PD-conjugated monomeric and dimeric RGD peptides, PD-K-(¹¹¹In-DOTA)-c(RGDfK) and PD-K(¹¹¹In-DOTA)-E[c(RGDfK)]₂, and evaluated their albumin binding. We compared pharmacokinetics with and without PD in tumor-bearing mice. The therapeutic effects of PD-K(¹⁷⁷Lu-DOTA)-c(RGDfK) (7.5, 15, and 30 MBq) and PD-K(²²⁵Ac-DOTA)-c(RGDfK) (20 and 40 kBq) were investigated in tumor-bearing mice. ¹⁷⁷Lu-DOTA-c(RGDfK) (30 MBq) was used as a control to evaluate the therapeutic effects of PD conjugation in comparison with PD-K(¹⁷⁷Lu-DOTA)-c(RGDfK). An in vitro binding study using HSA showed that the conjugation of PD significantly enhanced the albumin-binding ability. The albumin-binding percentages of ¹¹¹In-DOTA-c(RGDfK) and ¹¹¹In-DOTA-E[c(RGDfK)]₂ were less than 1%, while their PD conjugates were 50.93 ± 1.87 and 29.96 ± 1.60, respectively. A biodistribution study revealed that PD conjugates significantly prolonged blood clearance and increased tumor uptake. Unexpectedly, the tumor uptake of PD-K-(¹¹¹In-DOTA)-c(RGDfK) was more sustained than that of PD-K(¹¹¹In-DOTA)-E[c(RGDfK)]₂, corresponding to their albumin-binding ability. In the therapeutic experiments with PD-K(¹⁷⁷Lu-DOTA)-c(RGDfK), only 30 MBq suppressed tumor growth. PD-K(²²⁵Ac-DOTA)-c(RGDfK) significantly inhibited tumor growth; however, elevated ALT and AST levels were observed in mice treated with 40 kBq. Thus, PD conjugation successfully increased tumor uptake by prolonging blood clearance, leading to preferential therapeutic efficacy. This study demonstrated that PD-K(²²⁵Ac-DOTA)-c(RGDfK) enhanced the therapeutic effects of radionuclide therapy by sustaining high tumor uptake, which led to significant tumor growth inhibition and prolonged median survival time.

Gastric cancer is a prevalent and clinically significant gastrointestinal malignancy worldwide. Gastric cancer is characterized by limited treatment efficacy and a high recurrence rate. In this study, we found that LGALS9 was highly expressed in gastric cancer and may contribute to disease progression by modulating the infiltration of CD8⁺ T cells. Genetic knockout of LGALS9 reversed T cell function, attenuated immunosuppression, and enhanced the cytotoxic activity of T cells to kill gastric cancer cells. Furthermore, miR-491-5p was identified as a potential suppressor in gastric cancer. The microRNA miR-491-5p regulated T cell-mediated immunity by targeting and inhibiting LGALS9, which was similar to the effect of LGALS9 knockout. Overall, the key target LGALS9 and its inhibitor miR-491-5p represent promising potential for treating gastric cancer.

Based on mRNA Expression Profiles of 57 Patient-Derived Colorectal Cancer Stem-Like Cell (CRC-SC) Lines Compared With Normal Colonic Epithelial Stem-Like Cells (NCE-SCs), we Identified Five CRC Subtypes. The First Subtype of CRC-SCs Showed Markedly Increased Expression of MUC12, PIGR, PLA2G2A, SLC4A4, and ZG16, Which Were Barely Detectable in the Other Subtypes. Importantly, Their Expression Correlated With Favorable Outcomes in Both the Discovery Cohort and Independent Two Test Cohorts From Public Databases. The Remaining Four Subtypes Showed High Expression of DEFA6, BST2, MAGEA6, or IGF2 Compared With NCE-SCs. Although the Expression of Each Gene Individually Influenced Patient Outcomes, Additional Co-Expressed Genes Within Each Subtype Were Also Associated With Prognosis. Furthermore, Integrating the Five Subtype-Specific Signatures Produced a Practical Prognostic Indicator, Designated as the General Colorectal Cancer Signature (GCS), and Provided Individualized Predictive Signatures for Each Patient. The Clinical Significance of GCS Was Further Validated in a Novel Orthotopic Xenograft Mouse Model, Which Recapitulated Patient Outcomes: CRC-SCs With Low GCS Scores Developed Distinct Liver and Lung Metastases, Whereas Those With High Scores Did Not. Apparent Associations Were Observed Between Activating RAS/RAF Mutations and BST2 Expression, and Between the Absence of SMAD4 Mutation and IGF2 Expression, but These Had no Significant Impact on Patient Survival, Suggesting That Driver Gene Mutations May Not Directly Influence GCS. Collectively, Our Findings Provide a Comprehensive Overview of Clinically Relevant Molecular Subtypes of CRC-SCs, Representing the Current Landscape of CRC Molecular Expression Subtypes. They Also Enable Rapid, Low-Cost Outcome Prediction and Suggest Potential Targets for Therapeutics Development.

Cancer-associated fibroblasts (CAFs) play important roles in the progression of hepatocarcinoma, while the mechanism underlying the pro-invasive transformation of normal fibroblasts (NFs) to CAFs remains poorly defined. lncDILC is a long non-coding RNA previously identified to be downregulated in liver cancer stem cells. Here, we found that lncDILC was also significantly downregulated in liver cancer CAFs compared with NFs. Knockdown of lncDILC in NFs facilitated their conversion into CAFs, and enhanced the ability to promote the migration and invasion of liver cancer cells. Conversely, overexpression of lncDILC in CAFs ameliorated their invasive characteristics, and suppressed cancer cell metastasis. Moreover, we found miR-6071 acted as a target of lncDILC, and functioned as a transcriptive suppressor of zinc finger protein 395 (ZNF395), which exhibited an inhibitory effect on the pro-invasive conversion of fibroblasts. Overexpression of ZNF395 reversed the pro-invasive effects induced by lncDILC knockdown. These results elucidate a pathway of lncDILC-miR-6071-ZNF395 that suppresses the NF-CAF conversion, suggesting new therapeutic targets for the strategies for the treatment of liver cancer.

BRAF V600E-mutant colorectal cancer (CRC) represents a distinct molecular subtype with considerable heterogeneity in tumor biology and therapeutic response. Although gene expression-based classifications (BM1/BM2 subtypes) provide valuable insights into underlying molecular and immune features, their clinical application is limited by the need for high-throughput sequencing. This study aims to establish an immunohistochemistry (IHC)-based classification system to enable practical subtype stratification and aid prognostic and therapeutic evaluation. Using two independent cohorts (public dataset, n = 218; institutional cohort, n = 122), we performed differential expression analysis, machine learning modeling, and clinical feasibility evaluation. Fourteen candidate markers were identified, and a decision tree algorithm selected CD8 and ARHGEF17 as optimal classifiers. Based on these markers, two IHC-based subtypes were established: iBM1 (CD8⁺/ARHGEF17^-) and iBM2 (CD8^- with any ARHGEF17 expression or CD8⁺/ARHGEF17⁺). The IHC-based subtypes showed concordance with transcriptomic BM subtypes (training: 82.69%, κ = 0.55; validation: 72.22%, κ = 0.44; prospective: 83.33%, κ = 0.57). Transcriptomic profiling revealed enrichment of immune activation and epithelial-mesenchymal transition in iBM1, and cell cycle-related pathways in iBM2. In clinical validation, iBM1 was associated with poorer survival but greater sensitivity to immune checkpoint inhibitors. This IHC-based classification provides a practical and accessible approach for BM subtype stratification, reflecting underlying molecular and immune characteristics, and may support prognostic assessment and therapeutic decision-making in BRAF V600E-mutant CRC.

Investigating the phenotypic contribution of gene-spliced isoforms to tumor cellular heterogeneity can facilitate the development of innovative strategies for precision medicine. Serine protease 3 (PRSS3), a trypsin-like protease with four spliced variants (PRSS3-SVs: PRSS3-V1 to V4), plays diverse biological roles in cancer progression. Herein, we systematically analyzed the expression patterns and functional implications of PRSS3-SVs in gastric cancer (GC) using an integrative approach that combined bioinformatic analyses, CpG site-specific methylation detection, splice-specific qPCR, isoform-based methodologies, and multiple functional assays. Our findings revealed that differentially expressed PRSS3 isoforms, predominantly PRSS3-V1 and PRSS3-V2, are regulated by intragenic methylation and exert pleiotropic roles in GC. Overexpression of PRSS3 transcripts suppressed GC cell proliferation via the NF-κB signaling pathway, while exerting distinct effects on matrix metalloproteinase-associated cell migration and invasion. Clinically, patients with low PRSS3-V1 or high PRSS3-V2 expression exhibited poorer survival outcomes, and the expression difference between these two transcripts was identified as an independent prognostic indicator for GC patients. Epigenetically, differential methylation patterns within PRSS3 enabled stratification of GC patients into subgroups characterized by either high-methylation with low-expressed PRSS3-SVs or low-methylation with high-expressed PRSS3-SVs. The UHRF1/DNMT1 complex was found to mediate CpG site methylation and regulate PRSS3 transcripts, particularly silencing PRSS3-V1 through intragenic CpG methylation. This methylation pattern was associated with reduced survival rates and further validated its correlation with tumor metastasis in an independent cohort (n = 243). Our study elucidates that methylation-regulated alternative splicing contributes to phenotypic heterogeneity in GC, highlighting its potential advantage over differentially expressed genes in improving stratification strategies for precision oncology.