Translational Oncology最新文献

Objective

To demonstrate the feasibility of using focused ultrasound to enhance delivery of PD-1 inhibitors in glioma rats and determine if such an approach increases treatment efficacy.

Methods

C6 glioma in situ rat model was used in this study. Transcranial irradiation with FUS combined with microbubbles was administered to open the blood-brain barrier (BBB). The efficacy of BBB opening was evaluated in normal rats. The rats with glioma were grouped to evaluate the role of PD-1 inhibitors combined with FUS-induced immune responses in suppressing glioma when the BBB opens. Flow cytometry was used to examine the changes of immune cell populations of lymphocytes in peripheral blood, tumor tissue and spleen tissue of the rats. A section of rat brain tissue was also used for histological and immunohistochemical analysis. The survival of the rats was then monitored; the tumor progression and changes in blood perfusion of tumor were dynamically observed in vivo using multimodal MRI.

Results

FUS combined with microbubbles could enhance the blood perfusion of tumors by increasing the permeability of BBB (p < 0.0001), thus promoting the infiltration of CD4⁺ T lymphocytes (p < 0.01). Compared with the control group, the combination treatment group had increased in the infiltration number of CD4⁺(p < 0.05) and CD8⁺ T (p < 0.05); the tumor volume of the combined treatment group was smaller than that of the control group (p < 0.01) and the survival rate of the rats was prolonged (p < 0.05).

Conclusions

In this study, we demonstrated that the transient opening of the BBB induced by FUS enhanced tumor vascular perfusion and facilitated the delivery of PD-1 inhibitors, ultimately improving the therapeutic efficacy for glioblastoma.

Background

Gastric cancer (GC) remains a significant global health challenge with poor prognosis, partly due to its ability to evade the immune system. The extracellular matrix (ECM), particularly collagen, plays a crucial role in tumor immune evasion, but the underlying mechanisms are not fully understood. This study investigates the role of collagen ECM in promoting immune evasion in gastric cancer by activating the IL4I1-AHR signaling pathway.

Methods

We cultured gastric cancer cells in 3D collagen gels and assessed their immune evasion capabilities by co-culturing with HER2-specific CAR-T cells. The expression of IL4I1 and its metabolites was analyzed, and the role of integrin αvβ1 in mediating the effects of collagen was explored. Additionally, the impact of IL4I1-induced AHR activation on CAR-T cell exhaustion was evaluated, both in vitro and in vivo.

Results

We found that gastric cancer cells cultured on collagen exhibited increased resistance to CAR-T cell cytotoxicity, which was associated with upregulated immune checkpoint molecules and downregulated effector cytokines on CAR-T cells. This was linked to increased IL4I1 expression, which was further induced by integrin αvβ1 signaling within the 3D collagen environment. IL4I1 metabolites, particularly KynA, promoted CAR-T cell exhaustion by activating the AHR pathway, leading to decreased cytotoxicity and tumor growth inhibition.

Conclusions

Our study reveals a novel mechanism by which the collagen ECM facilitates immune evasion in gastric cancer through the activation of IL4I1-AHR signaling, contributing to CAR-T cell exhaustion. Targeting this pathway could potentially enhance the efficacy of CAR-T cell therapy in gastric cancer.

Background

The Ubiquitin-proteasome system (UPS) is known to participate in multiple cellular events. The deubiquitinating enzyme USP2 (ubiquitin-specific protease 2) is involved in the vasculature remodeling process associated with bladder cancer (BLCA). However, the role of USP2 in BLCA progression has not been clearly defined and whether its regulatory mechanism involving EZH2 (Enhancer of Zeste Homolog 2) remains elusive yet.

Methods

Differential expression patterns of USP2 and EZH2 were examined in 46 pairs of BLCA and adjacent normal tissues. USP2 knockdown plasmids were transfected into 5637 and J82 cells to detect its impact on cell proliferation, migration and invasion using CCK-8, EdU, wound healing and transwell assays. The USP2-EZH2-SOX1 cascade was confirmed through Co-immunoprecipitation (Co-IP) and chromatin immunoprecipitation (ChIP) assays. An in vivo verification was conducted using a xenograft model of nude mice.

Results

USP2 was significantly upregulated in BLCA tissues and cells, which was associated with poor clinical prognosis in BLCA patients. USP2 depletion resulted in decreased cell proliferation, migration and invasion in BLCA cells. USP2 stabilized the EZH2 protein by directly binding to it, thereby reducing its ubiquitination. Ectopic introduction of EZH2 restored cell growth and invasion of BLCA cells, which had been inhibited by USP2 silencing. USP2-mediated stabilization of EZH2 promoted the enrichment of histone H3K27me3 and repression of SOX1. Involvement of the USP2-EZH2-SOX1 axis in tumor formation was ultimately verified in vivo.

Conclusion

Our findings reveal that a USP2-EZH2-SOX1 axis orchestrates the interplay between dysregulated USP2 and EZH2-mediated gene epigenetic silencing in BLCA progression.

Background

Previous research has elaborated on the role of long non-coding RNA LINC00173 in the pathogenesis of various cancers; however, our knowledge of its clinical consequences and mechanisms in endometrial cancer (EC) is limited. Our current work is aimed at investigating the effect of LINC00173 in combination with its upstream gene HNRNPC on EC progression.

Methods

LINC00173 and HNRNPC levels were investigated by qRT-PCR or western blotting in EC tissues. The functional roles of HNRNPC and LINC00173 were assessed using transwell, colony formation and CCK-8 assays. A xenograft was used to verify the phenotype of LINC00173 after its overexpression. The regulatory role between HNRNPC and LINC00173 was investigated using RIP and RNA pull-down analysis.

Results

In EC tissues, LINC00173 expression was down-regulated. We observed that increased LINC00173 inhibited EC cell growth and migration. LINC00173 was a downstream target of HNRNPC, and its expression level was elevated by HNRNPC silencing. LINC00173 overexpression shifted part of HNRNPC into the cytoplasm from the nucleus of EC cells. Furthermore, HNRNPC expression was upregulated in EC and its silencing inhibited EC cell malignancy in vitro.

Conclusion

LINC00173 can impair the malignancy of EC cell by interacting with HNRNPC. This finding may contribute to the understanding of the tumorigenic effects of HNRNPC and LINC00173 on EC.

Background

HER2-targeted therapies have revolutionised the treatment of HER2-positive breast cancer. However, de novo resistance or the emergence of acquired resistance is a persistent clinical problem. Here we report that neratinib, an irreversible pan-HER inhibitor, in combination with the multi-kinase inhibitor dasatinib, currently used to treat certain leukemias, has strong anti-proliferative effects against models of HER2-positive breast cancer that are innately resistant to trastuzumab or have acquired resistance to neratinib.

Methods

Neratinib plus dasatinib was examined in a panel of 20 breast cancer cell lines, including HER2-positive, estrogen-receptor-positive, triple negative, and acquired HER2-targeted therapy resistant models. Drug effects on migration and apoptosis induction was evaluated and signaling alterations were determined by reverse phase protein array (RPPA). In vivo efficacy was examined using orthotopically-implanted HCC1954 cells.

Results

Synergy was observed in cell lines innately resistant to trastuzumab, models with acquired resistance to neratinib, and in triple negative breast cancer cell lines. Further investigation showed that neratinib plus dasatinib induced apoptosis and inhibited cell migration to a greater degree than either drug alone. RPPA revealed that the combination caused suppression of key survival signaling through EGFR, Akt, and MAPK inhibition. In vivo, neratinib plus dasatinib was well tolerated and had a prolonged anti-tumor effect against HCC1954 xenografts.

Conclusions

This study provides a strong pre-clinical rationale for the clinical investigation neratinib and dasatinib in HER2+ breast cancer.

The progression of hepatocellular carcinoma (HCC) is influenced by disrupted metabolic processes, presenting challenges in prognostic outcomes. Hepatocellular carcinoma (HCC), a leading cause of cancer-related mortality, is closely associated with metabolic reprogramming and stem cell-like properties in liver cancer stem cells (LCSCs). This study explored the potential molecular mechanisms by which tLyP-1-modified extracellular vesicles (EVs) delivering CTCF shRNA (tLyp-1-EV-shCTCF) regulate mitochondrial DNA methylation-induced glycolytic metabolic reprogramming and LCSC self-renewal. Through a series of methods, including Western blot, nanoparticle tracking analysis, and immunofluorescence, we demonstrated the successful delivery and internalization of tLyp-1-EV in HCC cells. Our results identified SALL3 as a critical factor underexpressed in HCC and LCSCs, while CTCF was overexpressed. Overexpression of SALL3 inhibited LCSC self-renewal and immune evasion by blocking the CTCF-DNMT3A interaction, thus repressing DNMT3A methyltransferase activity and subsequent mitochondrial DNA methylation-mediated glycolytic metabolic reprogramming. In vivo experiments further supported these findings, showing that tLyp-1-EV-shCTCF treatment significantly reduced tumor growth by upregulating SALL3 expression, thereby inhibiting glycolytic metabolic reprogramming and enhancing the immune response against HCC cells. This study provides novel insights into the role of SALL3 and mitochondrial DNA methylation in HCC progression, offering potential therapeutic targets for combating HCC and its stem cell-like properties.

This study aims to identify key regulators of paraptosis in gastric cancer (GC) and explore their potential in guiding therapeutic strategies, especially in stomach adenocarcinoma (STAD). Genes associated with paraptosis were identified from the references and subjected to Cox regression analysis in the TCGA-STAD cohort. Using machine learning models, LPAR1 consistently ranked highest in feature importance. Multiple sequencing data showed that LPAR1 was significantly overexpressed in cancer-associated fibroblasts (CAFs). LPAR1 expression was significantly higher in normal tissues, and ROC analysis demonstrated its discriminative ability. Copy number alterations and microsatellite instability were significantly associated with LPAR1 expression. High LPAR1 expression correlated with advanced tumor grades and specific cancer immune subtypes, and multivariate analysis confirmed LPAR1 as an independent predictor of poor prognosis. LPAR1 expression was associated with different immune response metrics, including immune effector activation and upregulated chemokine secretion. High LPAR1 expression also correlated with increased sensitivity to compounds, such as BET bromodomain inhibitors I-BET151 and RITA, suggesting LPAR1 as a biomarker for predicting drug activity. FOXP2 showed a strong positive correlation with LPAR1 transcriptional regulation, while increased methylation of LPAR1 promoter regions was negatively correlated with gene expression. Knockdown of LPAR1 affected cell growth in most tumor cell lines, and in vitro experiments demonstrated that LPAR1 influenced extracellular matrix (ECM) contraction and cell viability in the paraptosis of CAFs. These findings suggest that LPAR1 is a critical regulator of paraptosis in GC and a potential biomarker for drug sensitivity and immunotherapy response. This underscores the role of CAFs in mediating tumorigenic effects and suggests that targeting LPAR1 could be a promising strategy for precision medicine in GC.

Triple-negative breast cancer (TNBC) is a challenging subtype with unclear biological mechanisms. Recently, the transcription factor androgen receptor (AR) and its regulation of the DLGAP5 gene have gained attention in TNBC pathogenesis. In this study, we found a positive correlation between high AR expression and TNBC cell proliferation and growth. Furthermore, we confirmed DLGAP5 as a critical downstream regulator of AR with high expression in TNBC tissues. Knockdown of DLGAP5 significantly inhibited TNBC cell proliferation, migration, and invasion. AR was observed to directly bind to the DLGAP5 promoter, enhancing its transcriptional activity and suppressing the activation of the p53 signaling pathway. In vivo experiments further validated that downregulation of AR or DLGAP5 inhibited tumor growth and enhanced CD8⁺ T cell infiltration. This study highlights the crucial roles of AR and DLGAP5 in TNBC growth and immune cell infiltration. Taken together, AR inhibits the p53 signaling pathway by promoting DLGAP5 expression, thereby impacting CD8⁺ T cell infiltration in TNBC.

Objective

Mitomycin C (MMC), a DNA-damaging chemotherapeutic, is commonly used clinically for recurrent cervical carcinoma (CC), either alone or in combination. MMC generates DNA damage resulting in CC cell death yet also induces increased AKT-BAD phosphorylation associated with drug resistance and reduced clinical benefit. The present study evaluates the efficacy of combined MMC and a BAD phosphorylation inhibitor in CC.

Methods

The association and function of phosphorylation of BAD on serine 99 (pBADS99) for cell survival of both MMC-resistant or sensitive-CC cells was explored. BAD was mutated to BADS99A to examine the requirement of BADS99 for CC cell survival and a novel small-molecule inhibitor of pBADS99 was utilized. Cell proliferation, survival, foci formation, and patient-derived organoids (PDOs) assays were utilized to determine efficacy, synergy and related mechanisms.

Results

MMC IC₅₀ was positively correlated to the cell line pBADS99/BAD ratio. Increased BADS99 phosphorylation was observed in both MMC-sensitive or -resistant CC cells after MMC treatment. Inhibition of pBADS99 in CC cell lines produced synergistic apoptosis through BAD-mediated apoptotic pathways and enhanced DNA damage in response to MMC. The concurrent use of pharmacological inhibition of pBADS99 and MMC was synergistic, resulting in diminished cell viability and inducing apoptotic cell death in MMC-sensitive and -resistant CC cell lines or patient-derived organoids.

Conclusion

A combination of MMC with inhibition of BAD phosphorylation potentiated efficacy compared to single agent treatment. The potential further development of such strategies may provide outcome benefits to patients with CC.

Photodynamic therapy (PDT) is considered as a promising anticancer approach, owning to its high efficiency and spatiotemporal selectivity. Ample evidence indicated that PDT can trigger immunogenic cell death by releasing antigens that activate immune cells to promote anti-tumor immunity. Nevertheless, the inherent nature of tumors and their complex heterogeneity often limits the efficiency of PDT, which can be overcome with a novel strategy of photo-immunotherapy (PIT) strategy. By exploring the principles of PDT induction and ICD enhancement, combined with other therapies such as chemotherapy or immune checkpoint blockade, the tailored solutions can be designed to address specific challenges of drug resistance, hypoxic conditions, and tumor immunosuppressive microenvironments (TIMEs), which enables targeted enhancement of systemic immunity to address most distant and recurrent cancers. The present article summarizes the specific strategies of PIT and discusses recent existing limitations. More importantly, we anticipate that the perspectives presented herein will help address the clinical translation challenges associated with PIT.