SERPINE2 promotes liver cancer metastasis by inhibiting c-Cbl-mediated EGFR ubiquitination and degradation.

BACKGROUND: Liver cancer is a malignancy with high morbidity and mortality rates. Serpin family E member 2 (SERPINE2) has been reported to play a key role in the metastasis of many tumors. In this study, we aimed to investigate the potential mechanism of SERPINE2 in liver cancer metastasis. METHODS: The Cancer Genome Atlas database (TCGA), including DNA methylation and transcriptome sequencing data, was utilized to identify the crucial oncogene associated with DNA methylation and cancer progression in liver cancer. Data from the TCGA and RNA sequencing for 94 pairs of liver cancer tissues were used to explore the correlation between SERPINE2 expression and clinical parameters of patients. DNA methylation sequencing was used to detect the DNA methylation levels in liver cancer tissues and cells. RNA sequencing, cytokine assays, immunoprecipitation (IP) and mass spectrometry (MS) assays, protein stability assays, and ubiquitination assays were performed to explore the regulatory mechanism of SERPINE2 in liver cancer metastasis. Patient-derived xenografts and tumor organoid models were established to determine the role of SERPINE2 in the treatment of liver cancer using sorafenib. RESULTS: Based on the public database screening, SERPINE2 was identified as a tumor promoter regulated by DNA methylation. SERPINE2 expression was significantly higher in liver cancer tissues and was associated with the dismal prognosis in patients with liver cancer. SERPINE2 promoted liver cancer metastasis by enhancing cell pseudopodia formation, cell adhesion, cancer-associated fibroblast activation, extracellular matrix remodeling, and angiogenesis. IP/MS assays confirmed that SERPINE2 activated epidermal growth factor receptor (EGFR) and its downstream signaling pathways by interacting with EGFR. Mechanistically, SERPINE2 inhibited EGFR ubiquitination and maintained its protein stability by competing with the E3 ubiquitin ligase, c-Cbl. Additionally, EGFR was activated in liver cancer cells after sorafenib treatment, and SERPINE2 knockdown-induced EGFR downregulation significantly enhanced the therapeutic efficacy of sorafenib against liver cancer. Furthermore, we found that SERPINE2 knockdown also had a sensitizing effect on lenvatinib treatment. CONCLUSIONS: SERPINE2 promoted liver cancer metastasis by preventing EGFR degradation via c-Cbl-mediated ubiquitination, suggesting that inhibition of the SERPINE2-EGFR axis may be a potential target for liver cancer treatment.

WZ35 inhibits gastric cancer cell metastasis by depleting glutathione to promote cellular metabolic remodeling.

This study aimed at elucidating the crosstalk between redox reaction and metabolic remodeling through uncovering the mechanism underlying WZ35-mediated reactive oxygen species (ROS) production and regulation of amino acid metabolism to inhibit gastric cancer (GC) cell metastasis. The activity and biosafety of curcumin analog, WZ35, were verified in vitro and in vivo. The potential molecular mechanism underlying WZ35-mediated enhanced radiotherapeutic sensitivity by reduced Glutathione (GSH) depletion was elucidated by RNA sequencing, single-cell sequencing (scRNA-seq), metabolic mass spectrometry, and other molecular experiments. Compared to curcumin, WZ35 proved more potent anti-proliferative and anti-metastasis properties. Importantly, we demonstrated that WZ35 could consume GSH in multiple ways, including by reduction of raw materials and consumption reserves, inhibition of reformation, and enhanced decomposition. Mechanistically, we identify that WZ35 maintains the GSH depletion phenotype through the ROS-YAP-AXL-ALKBH5-GLS2 loop, further backing the relevance of metabolic remodeling in the tumor microenvironment with tumor metastasis and the role of m6A in tumor metastasis. Collectively, our study identified WZ35 as a novel GSH depletion agent and a previously undiscovered GSH depletion loop mechanism in GC cell metastasis.

Curcumin micelles suppress gastric tumor cell growth by upregulating ROS generation, disrupting redox equilibrium and affecting mitochondrial bioenergetics.

Gastric cancer is the fourth most common cancer and the second most frequent cause of cancer death worldwide. Chemotherapy is an important treatment. However, traditional chemotherapy drugs have low bioavailability and targeting ability. Therefore, we developed curcumin-encapsulated micelles for the treatment of gastric cancer and investigated their antitumor efficacy and active mechanism. Gastric cancer cells were treated with different concentrations of curcumin micelles. MTS cell proliferation assays, flow cytometry (FCM), real time cellular analysis (RTCA) and nude mice xenografts were used to evaluate the effects of curcumin micelles on gastric cancer cell growth in vitro and in vivo. Western blotting was performed to analyze the protein levels of the indicated molecules. A Seahorse bioenergetics analyzer was used to investigate alterations in oxygen consumption and the aerobic glycolysis rate. Curcumin micelles significantly inhibited proliferation and colony formation and induced apoptosis in gastric tumor cells compared to the control groups. We further investigated the mechanism of curcumin micelles on gastric tumor cells and demonstrated that curcumin micelles acted on mitochondrial proteins, causing changes in mitochondrial function and affecting mitochondrial bioenergetics. Furthermore, curcumin micelles decreased mitochondrial membrane potential, increased reactive oxygen species (ROS) generation and disrupted redox equilibrium. The nude mouse model verified that curcumin micelle treatment significantly attenuated tumor growth in vivo. Curcumin micelles suppress gastric tumor cell growth in vitro and in vivo. The mechanism may be related to increasing ROS generation, disrupting redox equilibrium and affecting mitochondrial bioenergetics.

The curcumin analogue WZ35 affects glycolysis inhibition of gastric cancer cells through ROS-YAP-JNK pathway.

To investigate the anti-tumor activities of WZ35 and its possible molecular mechanism, bioinformatics analysis and the hematoxylin-eosin (HE) staining were applied to evaluate the Yes-associated-protein (YAP) level in gastric cancer. Cell counting kit-8 (CCK-8) was used to examine cell viability. Apoptosis was determined by flow cytometry analysis. Seahorse bioenergetics analyzer was used to investigate the alteration of oxygen consumption and aerobic glycolysis rate. SiRNA transfection was applied to silence endogenous YAP. Western blot was performed to detect indicated proteins. We found that treatment of gastric cancer cells with WZ35 exerted stronger anti-tumor activities than curcumin. Mechanistically, our research showed that WZ35 inhibited glycolysis, and induced reactive oxygen species (ROS) generation, resulting in Jun N-terminal Kinase (JNK) activation through downregulation of YAP in gastric cancer cells. ROS mediated YAP downregulation and JNK activation was regulated by glycolysis. Abrogation of ROS production markedly attenuated WZ35 induced anti-tumor activities as well as YAP downregulation and JNK activation. Similarly, the JNK inhibitor significantly reversed WZ35 induced anti-tumor activities in gastric cancer cells. Our study reveals a novel anti-gastric cancer mechanism of WZ35 by inhibiting glycolysis through the ROS-YAP-JNK pathway. WZ35 might be a potential therapeutics for the treatment of gastric cancer.