CRIP1 Reshapes the Gastric Cancer Microenvironment to Facilitate Development of Lymphatic Metastasis

The MIR181A2HG/miR-5680/VCAN-CD44 Axis Regulates Gastric Cancer Lymph Node Metastasis by Promoting M2 Macrophage Polarization

BACKGROUND

Lymphatic metastasis in gastric cancer (GC) profoundly influences its prognosis, but the precise mechanism remains elusive. In this study, we identified the long noncoding RNA MIR181A2HG as being upregulated in GC and associated with LNs metastasis and prognosis.

METHODS

The expression of MIR181A2HG in GC was identified through bioinformatics screening analysis and qRT-PCR validation. Both in vitro and in vivo functional studies revealed that MIR181A2HG facilitates lymphangiogenesis and lymphatic metastasis. Techniques such as immunofluorescence, immunohistochemistry, qRT-PCR, ELISA, CHIP, RNA-pulldown, luciferase reporter assay, and Co-IP were employed to investigate the mechanism of MIR181A2HG in LNs metastasis of GC.

RESULTS

MIR181A2HG overexpressed in GC signifies an unfavorable prognosis and drives M2 polarization of TAMs enhancing lymphangiogenesis. Mechanistically, MIR181A2HG/miR-5680 axis as a novel ceRNA regulatory axis to upregulate versican (VCAN). On one hand, VCAN interacts with CD44 receptors on the surface of TAMs through paracrine secretion, promoting M2 macrophage polarization and subsequently enhancing the secretion of VEGF-C, ultimately facilitating lymphangiogenesis. On the other hand, VCAN binds to CD44 receptors on the surface of GC cells through autocrine secretion, activating the Hippo pathway and upregulating SP1, thereby promoting the transcription of MIR181A2HG and establishing a feedback loop driving lymphatic metastasis.

CONCLUSION

This study highlights the pivotal role of MIR181A2HG in GC progression and LNs metastasis. MIR181A2HG-based targeted therapy would represent a novel strategy for GC.

Noninvasive Assessment of Vascular Endothelial Growth Factor and Prognosis in Gastric Cancer Through Radiomic Features

INTRODUCTION

Gastric cancer (GC) is a leading cause of cancer-related deaths worldwide, with delayed diagnosis often limiting effective treatment options. This study introduces a novel, noninvasive radiomics-based approach using [18F] FDG PET/CT (fluorodeoxyglucose positron emission tomography/computed tomography) to predict vascular endothelial growth factor (VEGF) status and survival in patients with GC. The ability to noninvasively assess these parameters can significantly influence therapeutic decisions and outcomes.

METHODS

We conducted a retrospective study involving patients diagnosed with GC, stratified into training, validation, and test groups. Each patient underwent a [18F] FDG PET/CT scan, and radiomic features were extracted using dedicated software. A Radiomics Score (RS) was calculated, serving as a predictor for VEGF status. Statistical analyses included logistic regression and Cox proportional hazards models to evaluate the predictive power of RS on survival outcomes.

RESULTS

The developed radiomics model demonstrated high predictive accuracy, with the RS formula achieving an area under the receiver operating characteristic curve of 0.861 in the training cohort and 0.857 in the validation cohort for predicting VEGF status. The model also identified RS as an independent prognostic factor for survival, where higher RS values correlated with poorer survival rates.

DISCUSSION

The findings underscore the potential of [18F] FDG PET/CT radiomics in transforming the management of GC by providing a noninvasive means to assess tumor aggressiveness and prognosis through VEGF status. This model could facilitate earlier and more tailored therapeutic interventions, potentially improving survival outcomes in a disease marked by typically late diagnosis and limited treatment success.

Cellular components of tumor microenvironment: understanding their role in lymphatic metastasis of tumors

Metastasis is the leading cause of cancer-related death in cancer patients. Tumor cells primarily spread through the hematogenous and lymphatic system. The underlying mechanisms of hematogenous metastasis have been well described over the past few decades. However, the understanding of the molecular mechanisms involved in lymphatic metastasis is still at an early stage. Tumor microenvironment (TME), primarily consisting of T cells, B cells, tumor-associated macrophages, neutrophils, and cancer-associated fibroblasts, has been implicated in the development of lymphatic metastasis. Recent studies have been reported that the dynamic and complex interplay between these cellular components of TME has great effects on lymphatic metastasis. Here, we discussed the paradoxical roles of these cellular component within the TME during lymphatic metastasis, as well as potential therapeutic opportunities to re-educate these cells within the TME to have anti-tumorigenic effects.

circUBE2G1 interacts with hnRNPU to promote VEGF-C-mediated lymph node metastasis of lung adenocarcinoma

Background

Patients with lymph node(LN)metastasis-positive Lung adenocarcinoma(LUAD)suffer from a significantly reduced five-year survival rate. Increasing evidence indicates circular RNAs(circRNAs)play crucial roles in regulating cancer progression. However, the specific regulatory mechanisms of circRNAs in the LN metastasis of LUAD have not been fully explored.

Methods

GEO datasets and sequence analysis were applied for the identification of differentially expressed circRNAs between LUAD tissues and adjacent normal tissues. In vitro and in vivo experiments were performed to evaluate the function of circUBE2G1. The interaction between circUBE2G1 and VEGF-C was determined by RNA pulldown, ChIP, ChIRP and luciferase assays.

Results

In this study, we identified a novel circRNA, circUBE2G1 (hsa_circ_0041555), which is upregulated in LUAD and positively correlated with LN metastasis in patients with LUAD. Functionally, overexpression of circUBE2G1 promotes lymphangiogenesis and LN metastasis of LUAD both in vitro and in vivo. Mechanistically, circUBE2G1 activates the transcription of vascular endothelial growth factor C (VEGF-C) by recruiting hnRNPU to enhance H3K27ac on the VEGF-C promoter, thereby facilitating lymphangiogenesis and LN metastasis in LUAD.

Conclusion

Our findings offer new insights into the mechanisms behind circRNA-mediated LN metastasis in LUAD and suggest that circUBE2G1 may serve as a potential therapeutic target for LN metastasis in LUAD.

Tumor-associated lymphatic vessel density is a reliable biomarker for prognosis of esophageal cancer after radical resection: a systemic review and meta-analysis

Purpose

To explore whether tumor-associated lymphatic vessel density (LVD) could be a biomarker for the prognosis of patients with esophageal cancer after radical resection.

Methods

A systematic literature search was performed through PubMed, EMBASE, Wanfang Data, and Cochrane Library from the inception of databases until March 19, 2024. The selected studies investigated overall survival (OS) and/or recurrence-free survival (RFS) of patients with esophageal cancer with different levels of LVD after radical resection. The OS and RFS data were pooled as hazard ratios (HR) and 95% confidential interval (CI). Furthermore, the standardized mean differences (SMDs) and 95% CI were aggregated to evaluate the correlation between LVD and clinicopathological features.

Results

A total of 10 retrospective studies of 1,201 patients were finally included for the meta-analysis. Patients with esophageal cancer with a high level of LVD exhibited worse OS (HR 1.65, 95% CI 1.18 to 2.31) and RFS (HR 1.57, 95% CI 1.09 to 2.26) than those with a low level of LVD. Subgroup analysis of different pathological subtypes revealed that patients with esophageal adenocarcinoma with a high level of LVD had significantly worse RFS (HR 2.84, 95% CI 1.61 to 5.02) than those with a low level of LVD; while patients with esophageal squamous cell carcinoma with a high level of LVD had similar OS (HR 1.52, 95% CI 0.93 to 2.47) and RFS (HR 1.03, 95% CI 0.72 to 1.48) to those with a low level of LVD. Furthermore, tumors with lymph node metastasis had significantly higher levels of LVD than those without lymph node metastasis (SMD = 1.11, 95% CI 0.54 to 1.67). Tumors at the stages III-IV had significantly higher levels of LVD than those at the stages I-II (SMD = 1.62, 95% CI 0.90 to 2.34).

Conclusion

A high level of LVD in tumor was associated with worse survival of patients with esophageal cancer after radical resection, especially in patients with esophageal adenocarcinoma. Tumor-associated LVD is a new parameter that should be measured in postoperative pathology for predicting the prognosis of patients with esophageal cancer.

Systematic review registration

https://www.crd.york.ac.uk/prospero/ PROSPERO, identifier CRD42024553766.

Single-cell landscape of intratumoral heterogeneity and tumor microenvironment remolding in pre-nodal metastases of breast cancer

BACKGROUND

The metastasis of cancer cells is influenced by both their intrinsic characteristics and the tumor microenvironment (TME). However, the molecular mechanisms underlying pre-nodal metastases of breast cancer remain unclear.

METHODS

We integrated a total of 216,963 cells from 54 samples across 6 single-cell datasets to profile the cellular landscape differences between primary tumors and pre-nodal metastases.

RESULTS

We revealed three distinct metastatic epithelial cell subtypes (Epi1, Epi2 and Epi3), which exhibited different metastatic mechanisms. Specifically, the marker gene KCNK15 of the Epi1 subtype exhibited increased gene expression along the cell differentiation trajectory and was specifically regulated by the transcription factor ASCL1. In the Epi3 subtype, we highlighted NR2F1 as a regulator targeting the marker gene MUCL1. Additionally, we found that the Epi2 and Epi3 subtypes shared some regulons, such as ZEB1 and NR2C1. Similarly, we identified specific subtypes of stromal and immune cells in the TME, and discovered that vascular cancer-associated fibroblasts might promote capillary formation through CXCL9+ macrophages in pre-nodal metastases. All three subtypes of metastatic epithelial cells were associated with poor prognosis.

CONCLUSIONS

In summary, this study dissects the intratumoral heterogeneity and remodeling of the TME in pre-nodal metastases of breast cancer, providing novel insights into the mechanisms underlying breast cancer metastasis.

The GPI-anchor biosynthesis pathway is critical for syncytiotrophoblast differentiation and placental development

The glycosylphosphatidylinositol (GPI) biosynthetic pathway in the endoplasmic reticulum (ER) is crucial for generating GPI-anchored proteins (GPI-APs), which are translocated to the cell surface and play a vital role in cell signaling and adhesion. This study focuses on two integral components of the GPI pathway, the PIGL and PIGF proteins, and their significance in trophoblast biology. We show that GPI pathway mutations impact on placental development impairing the differentiation of the syncytiotrophoblast (SynT), and especially the SynT-II layer, which is essential for the establishment of the definitive nutrient exchange area within the placental labyrinth. CRISPR/Cas9 knockout of Pigl and Pigf in mouse trophoblast stem cells (mTSCs) confirms the role of these GPI enzymes in syncytiotrophoblast differentiation. Mechanistically, impaired GPI-AP generation induces an excessive unfolded protein response (UPR) in the ER in mTSCs growing in stem cell conditions, akin to what is observed in human preeclampsia. Upon differentiation, the impairment of the GPI pathway hinders the induction of WNT signaling for early SynT-II development. Remarkably, the transcriptomic profile of Pigl- and Pigf-deficient cells separates human patient placental samples into preeclampsia and control groups, suggesting an involvement of Pigl and Pigf in establishing a preeclamptic gene signature. Our study unveils the pivotal role of GPI biosynthesis in early placentation and uncovers a new preeclampsia gene expression profile associated with mutations in the GPI biosynthesis pathway, providing novel molecular insights into placental development with implications for enhanced patient stratification and timely interventions.

Lymphatic vessel: origin, heterogeneity, biological functions, and therapeutic targets

Lymphatic vessels, comprising the secondary circulatory system in human body, play a multifaceted role in maintaining homeostasis among various tissues and organs. They are tasked with a serious of responsibilities, including the regulation of lymph absorption and transport, the orchestration of immune surveillance and responses. Lymphatic vessel development undergoes a series of sophisticated regulatory signaling pathways governing heterogeneous-origin cell populations stepwise to assemble into the highly specialized lymphatic vessel networks. Lymphangiogenesis, as defined by new lymphatic vessels sprouting from preexisting lymphatic vessels/embryonic veins, is the main developmental mechanism underlying the formation and expansion of lymphatic vessel networks in an embryo. However, abnormal lymphangiogenesis could be observed in many pathological conditions and has a close relationship with the development and progression of various diseases. Mechanistic studies have revealed a set of lymphangiogenic factors and cascades that may serve as the potential targets for regulating abnormal lymphangiogenesis, to further modulate the progression of diseases. Actually, an increasing number of clinical trials have demonstrated the promising interventions and showed the feasibility of currently available treatments for future clinical translation. Targeting lymphangiogenic promoters or inhibitors not only directly regulates abnormal lymphangiogenesis, but improves the efficacy of diverse treatments. In conclusion, we present a comprehensive overview of lymphatic vessel development and physiological functions, and describe the critical involvement of abnormal lymphangiogenesis in multiple diseases. Moreover, we summarize the targeting therapeutic values of abnormal lymphangiogenesis, providing novel perspectives for treatment strategy of multiple human diseases.

Acid-sensing ion channel 1a modulation of apoptosis in acidosis-related diseases: implications for therapeutic intervention

Acid-sensing ion channel 1a (ASIC1a), a prominent member of the acid-sensing ion channel (ASIC) superfamily activated by extracellular protons, is ubiquitously expressed throughout the human body, including the nervous system and peripheral tissues. Excessive accumulation of Ca2+ ions via ASIC1a activation may occur in the acidified microenvironment of blood or local tissues. ASIC1a-mediated Ca2+‑induced apoptosis has been implicated in numerous pathologies, including neurological disorders, cancer, and rheumatoid arthritis. This review summarizes the role of ASIC1a in the modulation of apoptosis via various signaling pathways across different disease states to provide insights for future studies on the underlying mechanisms and development of therapeutic strategies.

Tumour-associated macrophages in gastric cancer: From function and mechanism to application

BACKGROUND

Gastric cancer (GC) is a malignant tumour, with high morbidity and mortality rates worldwide. The occurrence and development of GC is a complex process involving genetic changes in tumour cells and the influence of the surrounding tumour microenvironment (TME). Accumulative evidence shows that tumour-associated macrophages (TAMs) play a vital role in GC, acting as plentiful and active infiltrating inflammatory cells in the TME.

MAIN BODY

In this review, the different functions and mechanisms of TAMs in GC progression, including the conversion of phenotypic subtypes; promotion of tumour proliferation, invasion and migration; induction of chemoresistance; promotion of angiogenesis; modulation of immunosuppression; reprogramming of metabolism; and interaction with the microbial community are summarised. Although the role of TAMs in GC remains controversial in clinical settings, clarifying their significance in the treatment selection and prognostic prediction of GC could support optimising TAM-centred clinicaltherapy.

CONCLUSION

In summary, we reviewed the the phenotypic polarisation, function and molecular mechanism of TAMs and their potential applications in the treatment selection and prognostic prediction of GC.