RUNX1-BMP2 promotes vasculogenic mimicry in laryngeal squamous cell carcinoma via activation of the PI3K-AKT signaling pathway.

BACKGROUND: Laryngeal squamous cell carcinoma (LSCC) is one of the most common malignant tumors of the head and neck. Vasculogenic mimicry (VM) is crucial for tumor growth and metastasis and refers to the formation of fluid channels by invasive tumor cells rather than endothelial cells. However, the regulatory mechanisms underlying VM during the malignant progression of LSCC remain largely unknown. METHODS: Gene expression and clinical data for LSCC were obtained from the TCGA and Gene GEO (GSE27020) databases. A risk prediction model associated with VM was established using LASSO and Cox regression analyses. Based on their risk scores, patients with LSCC were categorized into high- and low-risk groups. The disparities in immune infiltration, tumor mutational burden (TMB), and functional enrichment between these two groups were examined. The core genes in LSCC were identified using the machine learning (SVM-RFE) and WGCNA algorithms. Subsequently, the involvement of bone morphogenetic protein 2 (BMP2) in VM and metastasis was investigated both in vitro and in vivo. To elucidate the downstream signaling pathways regulated by BMP2, western blotting was performed. Additionally, ChIP experiments were employed to identify the key transcription factors responsible for modulating the expression of BMP2. RESULTS: We established a new precise prognostic model for LSCC related to VM based on three genes: BMP2, EPO, and AGPS. The ROC curves from both TCGA and GSE27020 validation cohorts demonstrated precision survival prediction capabilities, with the nomogram showing some net clinical benefit. Multiple algorithm analyses indicated BMP2 as a potential core gene. Further experiments suggested that BMP2 promotes VM and metastasis in LSCC. The malignant progression of LSCC is promoted by BMP2 via the activation of the PI3K-AKT signaling pathway, with the high expression of BMP2 in LSCC resulting from its transcriptional activation by runt-related transcription factor 1 (RUNX1). CONCLUSION: BMP2 predicts poor prognosis in LSCC, promotes LSCC VM and metastasis through the PI3K-AKT signaling pathway, and is transcriptionally regulated by RUNX1. BMP2 may be a novel, precise, diagnostic, and therapeutic biomarker of LSCC.

PF-04449913 Inhibits Proliferation and Metastasis of Colorectal Cancer Cells by Down-regulating MMP9 Expression through the ERK/p65 Pathway.

INTRODUCTION: Colorectal cancer remains a life-threatening malignancy with increasing morbidity and mortality worldwide. Therefore, new and effective anti-colorectal cancer therapeutics are urgently needed. METHOD: In this study, we have studied the anti-tumor properties and potential mechanisms of PF-04449913. Colorectal cancer cell viability was reduced by PF-04449913 in a dose-dependent manner. The migration and invasion ability of malignant colon cells were attenuated by the drug, as demonstrated by the Transwell test. Moreover, PF-04449913 repressed the phosphorylation levels of ERK and other proteins, and the expression levels of MMP9. The anti-tumor effects of the drug in vivo were demonstrated in BALB/c-nude mice models, and PF-04449913 inhibited the malignant phenotype of colorectal cancer cells, including reduction of tumor size and promotion of apoptosis. At the molecular level, PF-04449913 induced a significant decrease in ERK and p65 protein phosphorylation levels and inhibited MMP9 protein expression. RESULTS: Both in vivo and in vitro results showed PF-04449913 to demonstrate antitumor effects, which have been proposed to be mediated through blockade of the ERK/p65 signaling pathway, and subsequent repression of MMP9 expression. CONCLUSION: Our study provides a new perspective on the potential clinical application of PF-04449913 in the treatment of colorectal cancer.

Astrocytic glycogen mobilization participates in salvianolic acid B-mediated neuroprotection against reperfusion injury after ischemic stroke.

Astrocytic glycogen serves as an important glucose reserve, and its degradation provides extra support for neighboring neurons during energy deficiency. Salvianolic acid B (SAB) exerts a neuroprotective effect on reperfusion insult after cerebrovascular occlusion, but the effect of SAB on astrocytic glycogen and its relationship with neuroprotection are not completely understood. Here, we knocked down astrocyte-specific glycogen phosphorylase (GP, the rate-limiting enzyme in glycogenolysis) in vitro and in vivo and investigated the changes in key enzymes in glycogen metabolism by performing immunoblotting in vitro and immunofluorescence in vivo. Neurobehavioral and morphological assessments were conducted to uncover the outcomes during brain reperfusion. SAB accelerated astrocytic glycogenolysis by upregulating GP activity but not GP expression after reperfusion. Suppression of astrocytic glycogenolysis weakened SAB-mediated neuroprotection against the reperfusion insult. In addition, activation of glycogenolysis by SAB contributed to the survival of astrocytes and surrounding neurons by increasing antioxidant levels in astrocytes. Our data reveal that astrocytic GP represents an important metabolic target in SAB-induced protection against brain damage after cerebrovascular recanalization.

Girdin influences pancreatic cancer progression by regulating c-MYC expression.

Pancreatic ductal adenocarcinoma is a complex gastrointestinal tumor with high metastatic potential and poor prognosis. Actin-binding protein Girdin is highly expressed in a variety of tumors and promotes tumorigenesis and progression. However, the mechanisms underlying the involvement of Girdin in pancreatic cancer have not been clarified. In this study, we observed that the expression of Girdin was upregulated in pancreatic cancer cells. The siRNA-mediated gene knockdown experiments showed that reduced expression of Girdin in pancreatic cancer cells inhibited cell proliferation, migration, and invasion while promoting cell apoptosis. Functional assays revealed that c-MYC overexpression in pancreatic cancer cells could significantly increase the cell proliferation ability and rates of cell migration and invasion while decreasing the apoptosis rate. It has been shown that phosphorylation plays a role in the functional regulation of the c-MYC gene. Subsequently, we examined the expression level of c-MYC in cells with manipulated expression of Girdin and identified a positive correlation between Girdin expression and c-MYC expression. Moreover, we found that Girdin knockdown in c-MYC-overexpressing pancreatic cancer cells slowed cell growth, blocked the cell cycle progression, significantly promoted apoptosis, and markedly decreased the cell migration and invasion. This finding indicated that silencing Girdin could mitigate the effect of c-MYC on promoting proliferation and metastasis of pancreatic cancer. Overall, this study provided evidence that Girdin promoted pancreatic cancer development presumably by regulating the c-MYC overexpression.

Chrysin inhibits hepatocellular carcinoma progression through suppressing programmed death ligand 1 expression.

BACKGROUNDS: The aberrant PD-L1 expression on cancer cells was confirmed to participate in immune evasion of hepatocellular carcinoma (HCC). Previous studies had documented that there were anti-tumorigenic effects of chrysin on HCC. However, whether chrysin can act on the over-expressed PD-L1 on HCC cells to exert the therapeutic effectiveness and the involved mechanisms has not yet been deciphered. PURPOSE: Herein, we aimed to explore the regulatory effects of chrysin on the PD-1/PD-L1 immune checkpoint and investigate its possible mechanisms in vivo and in vitro. METHODS: H22 xenograft mouse model was used to investigate the effects of chrysin on tumor growth and PD-L1 expression in tumors. In interferon-gamma (IFN-γ)-induced HepG2 cells, the cytotoxicity of chrysin was detected by MTT assay. Flow cytometry, ELISA and RT-PCR were carried out to evaluate the expression of PD-L1, and the expression of proteins in STAT3 and NF-κB pathways was also determined by Western blot. In HepG2 cells and Jurkat T cell co-culture system, ELISA kit was used to detect the level of IL-2, and T cell proliferation was further evaluated by CCK-8 method. RESULTS: Our data suggested that chrysin could effectively inhibit the progression of tumor, and promote the anti-tumor immunity of mice concomitant with enhanced CD4/CD8-positive T cell proportion in tumor tissues of H22 xenograft mouse model. Additionally, chrysin significantly down-regulated the expression of PD-L1 in vivo and in vitro, which was closely associated with the blockage of STAT3 and NF-κB pathways. Moreover, in the co-culture system, chrysin could increase the proliferation of T cells and the concentration of IL-2. CONCLUSION: These results indicate that chrysin may have the potential to be an immune checkpoint inhibitor for preventive or as an adjunctive curative agent for HCC.

Long non-coding RNA CASC2 inhibits breast cancer cell growth and metastasis through the regulation of the miR-96-5p/SYVN1 pathway.

Cancer susceptibility candidate 2 (CASC2), a long non-coding RNA (lncRNA), has been demonstrated to be a tumor suppressor in several types of cancer. However, the role and mechanism of CASC2 in breast cancer (BC) have not been investigated. In the present study, the expression and functions of CASC2 in BC were investigated. The expression of CASC2 was significantly decreased in BC tissues and cells compared with adjacent normal tissues and mammary epithelial cells, respectively. CASC2 overexpression inhibited the viability, migration and invasion, and elevated apoptosis of BC cells. In addition, CASC2 acted as a competing endogenous RNA for hsa-microRNA (miR)-96-5p and regulated the expression of its target gene, synoviolin (SYVN1). In miR-96-5p-overexpressed MDA-MB-231 cells, cell viability, migration and invasion was increased, and cell apoptosis was decreased, which was reversed by the upregulation of SYVN1. Taken together, the present study data indicated that decreased SYVN1 expression was a tumor suppressor, which inhibited the growth and metastasis of BC through the miR-96-5p/SYVN1 axis.

HRD1 suppresses the growth and metastasis of breast cancer cells by promoting IGF-1R degradation.

HRD1 (3-hydroxy-3-methylglutaryl reductase degradation) is an E3 ubiquitin ligase. We found that HRD1 was significantly downregulated in 170 breast cancer tissues. Low tumoral HRD1 expression was correlated with clinicopathological characteristics and a shorter survival in breast cancer patients. P65 specifically bound to the HRD1 promoter and inhibited HRD1 expression. Suppression of NF-κB activity reversed IL-6-induced downregulation of HRD1 expression. HRD1 interacted with IGF-1R and promoted its ubiquitination and degradation by the proteasome. Overexpression of HRD1 resulted in the inhibition of growth, migration and invasion of breast cancer cells in vitro and in vivo. Furthermore, HRD1 attenuated IL-6-induced epithelial-mesenchymal transition in MCF10A cells. These findings uncover a novel role for HRD1 in breast cancer.