Vasculogenic mimicry, a negative indicator for progression free survival of lung adenocarcinoma irrespective of first line treatment and epithelial growth factor receptor mutation status

Engineered in vivo and in vitro tumor model recapitulates vasculogenic mimicry signatures in melanoma

Vasculogenic mimicry (VM) describes a process by which tumor cells formed a novel microcirculation pattern in an endothelial cell-free manner. Clinically, VM is associated with aggressive phenotype and poor patient survival. However, the current models for investigating VM include 2D monolayer cultures, Matrigel-based cultures, and animal models, each of which has limitations. Matrigel-based models often exhibit batch-to-batch variations, while in vivo tumor models currently produce insufficient amounts of VM. There is currently no suitable tumor model to discover new therapeutic targets against VM. Herein, we establish an extracellular matrix (ECM)-based engineered tumor model in vivo and in vitro. In this study, we demonstrate that matrix proteins enhanced the VM formation in the engineered xenograft model. Furthermore, we also investigated the role of collagen/fibronectin (FN) in melanoma progression and VM formation. Compared with cells cultured on TCPS plates, the B16F10 cells cultured on collagen/FN coated plates showed increased proliferation and stemness, and significantly enhanced invasion and formation of VM networks. Molecular mechanism analysis showed that Integrin/VE-cadherin/EphA2/PI3K/MMP-2 signaling pathways are responsible for VM formation. Our results indicate that collagen/FN matrix plays an important role in VM formation in melanoma, suggesting that ECM protein is a potential therapeutic target for anti-VM therapy for melanoma.

Preoperative prediction of vasculogenic mimicry in lung adenocarcinoma using a CT radiomics model

AIM

To develop and validate a non-invasive computed tomography (CT)-based radiomics model for predicting vasculogenic mimicry (VM) status in lung adenocarcinoma (LA).

MATERIALS AND METHODS

Two hundred and three patients with LA were enrolled retrospectively and grouped into training and test groups with a ratio of 7:3. Uni- and multivariate logistic regression analyses were performed in the training cohort to screen the independent clinical and radiological factors for VM, and the clinical model was then established. A radiomics model was established based on the rad-scores through support vector machine (SVM). A radiomics nomogram model was subsequently constructed by combining the rad-score with clinical-radiological factors. The receiver operating characteristic curve (ROC), calibration curves, and decision curve analysis (DCA) were conducted to evaluate the performance of the three models.

RESULTS

Nine selected radiomics features were selected for the radiomics model and the maximum length and spiculation sign were constructed for the clinical model. The radiomics nomogram model integrating the maximum length, spiculation sign, and rad-score yielded the best AUC in both the training (AUC = 0.925) and test cohorts (AUC = 0.978), in comparison with the radiomics model (AUC = 0.907 and 0.964, in both the training and test cohorts) and the clinical model (AUC = 0.834 and 0.836 in both training and test cohorts).

CONCLUSIONS

The CT-based radiomics nomogram model showed satisfying discriminating performance for preoperatively and non-invasively predicting VM expression status in LA patients.

Acidosis promotes the metastatic colonization of lung cancer via remodeling of the extracellular matrix and vasculogenic mimicry

Acidosis is a hallmark of the tumor microenvironment caused by the metabolic switch from glucose oxidative phosphorylation to glycolysis. It has been associated with tumor growth and progression; however, the precise mechanism governing how acidosis promotes metastatic dissemination has yet to be elucidated. In the present study, a long‑term acidosis model was established using patient‑derived lung cancer cells, to identify critical components of metastatic colonization via transcriptome profiling combined with both in vitro and in vivo functional assays, and association analysis using clinical samples. Xenograft inoculates of 1 or 10 acidotic cells mimicking circulating tumor cell clusters were shown to exhibit increased tumor incidence compared with their physiological pH counterparts. Transcriptomics revealed that profound remodeling of the extracellular matrix (ECM) occurred in the acidotic cells, including upregulation of the integrin subunit α‑4 (ITGA4) gene. In clinical lung cancer, ITGA4 expression was found to be upregulated in primary tumors with metastatic capability, and this trait was retained in the corresponding secondary tumors. Expression of ITGA4 was markedly upregulated around the vasculogenic mimicry structures of the acidotic tumors, while acidotic cells exhibited a higher ability of vasculogenic mimicry in vitro. Acidosis was also found to induce the enrichment of side population cells, suggesting an enhanced resistance to noxious attacks of the tumor microenvironment. Taken together, these results demonstrated that acidosis actively contributed to tumor metastatic colonization, and novel mechanistic insights into the therapeutic management and prognosis of lung cancer were discussed.

Relationship between the expression of ARHGAP25 and RhoA in non-small cell lung cancer and vasculogenic mimicry

Background

Vasculogenic mimicry (VM) is a recently identified pattern of blood supply to tumor tissue. It has long been considered a functional element in the metastasis and prognosis of malignant tumors. Both Rho GTPase-activating protein 25 (ARHGAP25) and Ras homolog family member A (RhoA) are effective predictors of tumor metastasis. In this study, we examined the expression levels of ARHGAP25 and RhoA and the structure of VM in non-small cell lung cancer (NSCLC). At the same time, we used cytology-related experiments to explore the effect of ARHGAP25 on the migration ability of tumor cells. Furthermore, we analyzed the interaction between the three factors and their association with clinicopathological characteristics and the five-year survival time in patients using statistical tools.

Methods

A total of 130 well-preserved NSCLC and associated paracancerous tumor-free tissues were obtained. Cell colony formation, wound healing, and cytoskeleton staining assays were used to analyze the effect of ARHGAP25 on the proliferation and migration ability of NSCLC cells. Immunohistochemical staining was used to determine the positivity rates of ARHGAP25, RhoA, and VM. Statistical software was used to examine the relationships between the three factors and clinical case characteristics, overall survival, and disease-free survival.

Results

Cell colony formation, wound healing, and cytoskeleton staining assays confirmed that ARHGAP25 expression affects the proliferation and migratory abilities of NSCLC cells. ARHGAP25 positivity rates in NSCLC and paracancerous tumor-free tissues were 48.5% and 63.1%, respectively, whereas RhoA positivity rates were 62.3% and 18.5%, respectively. ARHGAP25 had a negative relationship with RhoA and VM, whereas RhoA and VM had a positive relationship (P < 0.05). ARHGAP25, RhoA, and VM affected the prognosis of patients with NSCLC (P < 0.05) according to Kaplan–Meier of survival time and Cox regression analyses. Furthermore, lowering ARHGAP25 expression increased NSCLC cell proliferation and migration.

Conclusions

ARHGAP25 and RhoA expression is associated with VM and may be of potential value in predicting tumor metastasis, prognosis, and targeted therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-02179-5.

Recent Progress in Second Near-Infrared (NIR-II) Fluorescence Imaging in Cancer

Cancer continues to be one of the leading causes of death worldwide, and its incidence is on the rise. Although cancer diagnosis and therapy have advanced significantly in recent decades, it is still a challenge to achieve the accurate identification and localization of cancer and to complete tumor elimination with a maximum preservation of normal tissue. Recently, second near-infrared region (NIR-II, 1000-1700 nm) fluorescence has shown great application potential in cancer theranostics due to its inherent advantages, such as great penetration capacity, minimal tissue absorption and scattering, and low autofluorescence. With the development of fluorescence imaging systems and fluorescent probes, tumor detection, margin definition, and individualized therapy can be achieved quickly, enabling an increasingly accurate diagnosis and treatment of cancer. Herein, this review introduces the role of NIR-II fluorescence imaging in cancer diagnosis and summarizes the representative applications of NIR-II image-guided treatment in cancer therapy. Ultimately, we discuss the present challenges and future perspectives on fluorescence imaging in the field of cancer theranostics and put forward our opinions on how to improve the accuracy and efficiency of cancer diagnosis and therapeutics.