The vacuolar H+-ATPase (V-ATPase) is an ATP-dependent proton pump that functions to control the pH of intracellular compartments as well as to transport protons across the plasma membrane of various cell types, including cancer cells. We have previously shown that selective inhibition of plasma membrane V-ATPases in breast tumor cells inhibits the invasion of these cells in vitro. We have now developed a nanobody directed against an extracellular epitope of the mouse V-ATPase c subunit. We show that treatment of 4T1-12B mouse breast cancer cells with this nanobody inhibits V-ATPase-dependent acidification of the media and invasion of these cells in vitro. We further find that injection of this nanobody into mice implanted with 4T1-12B cells orthotopically in the mammary fat pad inhibits metastasis of tumor cells to lung. These results suggest that plasma membrane V-ATPases represent a novel therapeutic target to limit breast cancer metastasis.

Metastasis is an important hallmark of malignant tumors, and telomerase often exhibits high expression in these tumors. Monitoring the real-time dynamics of telomerase will provide valuable insights into its association with tumor metastasis. In this study, we described a microfluidic system for screening highly metastatic sublines based on differential cell invasiveness, investigated telomerase expression in the process of tumor metastasis and explored the genes and signaling pathways involved in tumor metastasis. Cells with different metastasis abilities were efficiently classified into different channels, and the fluorescence imaging visually demonstrates that cells with higher metastasis ability have stronger telomerase activity. In addition, we successfully established the high-metastasis-ability LoVo subline (named as LoVo-H) and low-metastasis-ability LoVo subline (named as LoVo-L) from the human colorectal cancer LoVo cell lines through only one round of selection using the system. The results show that the LoVo-H cells display superior proliferation and invasiveness compared to LoVo-L cells. Furthermore, 6776 differentially expressed genes of LoVo-H compared with LoVo-L were identified by transcriptome sequencing. The genes associated with telomerase activity, cell migration and the epithelial to mesenchymal transition were up-regulated in LoVo-H, and PI3K-Akt signaling pathway, extracellular matrix-receptor interaction and Rap1 signaling pathway were significantly enriched in LoVo-H. This microfluidic system is a highly effective tool for selecting highly metastatic sublines and the LoVo-H subline established through this system presents a promising model for tumor metastasis research. Furthermore, this work preliminarily reveals telomerase expression during tumor metastasis and provides a new strategy for studying tumor metastasis and cancer diagnosis.

CD27 belongs to the tumor necrosis factor receptor superfamily and acts as a co-stimulatory molecule, modulating T and B cell responses. CD27 stimulation enhances T cell survival and effector functions, thus providing opportunities to develop therapeutic strategies. The current study aims to investigate the role of endogenous CD27 signaling in tumor growth and metastasis. CD8 + T cell-specific CD27 knockout (CD8Cre-CD27fl) mice were developed, while global CD27 knockout (KO) mice were also used in our studies. Flow cytometry analyses confirmed that CD27 was deleted specifically from CD8 + T cells without affecting CD4 + T cells, B cells, and HSPCs in the CD8Cre-CD27fl mice, while CD27 was deleted from all cell types in global CD27 KO mice. Tumor growth and metastasis studies were performed by injecting B16-F10 melanoma cells subcutaneously (right flank) or intravenously into the mice. We have found that global CD27 KO mice succumbed to significantly accelerated tumor growth compared to WT controls. In addition, global CD27 KO mice showed a significantly higher burden of metastatic tumor nests in the lungs compared to WT controls. However, there was no significant difference in tumor growth curves, survival, metastatic tumor nest counts between the CD8Cre-CD27fl mice and WT controls. These results suggest that endogenous CD27 signaling inhibits tumor growth and metastasis via CD8 + T cell-independent mechanisms in this commonly used melanoma model, presumably through stimulating antitumor activities of other types of immune cells.

Cancer metastasis poses significant challenges in current clinical therapy. Osthole (OST) has demonstrated efficacy in treating cervical cancer and inhibiting metastasis. Despite these positive results, its limited solubility, poor oral absorption, low bioavailability, and photosensitivity hinder its clinical application. To address this limitation, a glutathione (GSH)-responded nano-herb delivery system (HA/MOS@OST&L-Arg nanoparticles, HMOA NPs) is devised for the targeted delivery of OST with cascade-activatable nitric oxide (NO) release. The HMOA NPs system is engineered utilizing enhanced permeability and retention (EPR) effects and active targeting mediated by hyaluronic acid (HA) binding to glycoprotein CD44. The cargoes, including OST and L-Arginine (L-Arg), are released rapidly due to the degradation of GSH-responsive mesoporous organic silica (MOS). Then abundant reactive oxygen species (ROS) are produced from OST in the presence of high concentrations of NAD(P)H quinone oxidoreductase 1 (NQO1), resulting in the generation of NO and subsequently highly toxic peroxynitrite (ONOO-) by catalyzing guanidine groups of L-Arg. These ROS, NO, and ONOO- molecules have a direct impact on mitochondrial function by reducing mitochondrial membrane potential and inhibiting adenosine triphosphate (ATP) production, thereby promoting increased apoptosis and inhibiting metastasis. Overall, the results indicated that HMOA NPs has great potential as a promising alternative for the clinical treatment of cervical cancer.

Metastasis stands as the primary contributor to mortality associated with tumors. Chemotherapy and immunotherapy are frequently utilized in the management of metastatic solid tumors. Nevertheless, these therapeutic modalities are linked to serious adverse effects and limited effectiveness in preventing metastasis. Here, we report a novel therapeutic strategy named starvation-immunotherapy, wherein an immune checkpoint inhibitor is combined with an ultra-long-acting L-asparaginase that is a fusion protein comprising L-asparaginase (ASNase) and an elastin-like polypeptide (ELP), termed ASNase-ELP. ASNase-ELP\'s thermosensitivity enables it to generate an in-situ depot following an intratumoral injection, yielding increased dose tolerance, improved pharmacokinetics, sustained release, optimized biodistribution, and augmented tumor retention compared to free ASNase. As a result, in murine models of oral cancer, melanoma, and cervical cancer, the antitumor efficacy of ASNase-ELP by selectively and sustainably depleting L-asparagine essential for tumor cell survival was substantially superior to that of ASNase or Cisplatin, a first-line anti-solid tumor medicine, without any observable adverse effects. Furthermore, the combination of ASNase-ELP and an immune checkpoint inhibitor was more effective than either therapy alone in impeding melanoma metastasis. Overall, the synergistic strategy of starvation-immunotherapy holds excellent promise in reshaping the therapeutic landscape of refractory metastatic tumors and offering a new alternative for next-generation oncology treatments.

Neutrophil extracellular traps (NETs) are web-like structures composed of cytoplasmic contents, DNA chromatin and various granular proteins released by neutrophils in response to viruses, bacteria, immune complexes and cytokines. Studies have shown that NETs can promote the occurrence, development and metastasis of tumors. In this paper, the mechanism underlying the formation and degradation of NETs and the malignant biological behaviors of NETs, such as the promotion of tumor cell proliferation, epithelial mesenchymal transition, extracellular matrix remodeling, angiogenesis, immune evasion and tumor-related thrombosis, are described in detail. NETs are being increasingly studied as therapeutic targets for tumors. We have summarized strategies for targeting NETs or interfering with NET-cancer cell interactions and explored the potential application value of NETs as biomarkers in cancer diagnosis and treatment, as well as the relationship between NETs and therapeutic resistance.

Ovarian cancer is one of the most common gynecologic malignancies. Recurrence and metastasis often occur after treatment, and it has the highest mortality rate of all gynecological tumors. Cancer stem cells (CSCs) are a small population of cells with the ability of self-renewal, multidirectional differentiation, and infinite proliferation. They have been shown to play an important role in tumor growth, metastasis, drug resistance, and angiogenesis. Ovarian cancer side population (SP) cells, a type of CSC, have been shown to play roles in tumor formation, colony formation, xenograft tumor formation, ascites formation, and tumor metastasis. The rapid progression of tumor angiogenesis is necessary for tumor growth; however, many of the mechanisms driving this process are unclear as is the contribution of CSCs. The aim of this review was to document the current state of knowledge of the molecular mechanism of ovarian cancer stem cells (OCSCs) in regulating tumor angiogenesis.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors of the digestive system, and the exact mechanism of HCC is still unclear. Transcription factor 7 like 2 (TCF7L2) plays a pivotal role in cell proliferation and stemness maintenance. However, the exact mechanism of TCF7L2 in HCC remains unclear.
METHODS: Clinical samples and public databases were used to analyze the expression and prognosis of TCF7L2 in HCC. The function of TCF7L2 in HCC was studied in vitro and in vivo. ChIP and luciferase assays were used to explore the molecular mechanism of TCF7L2. The relationship between TCF7L2 and NEDD9 was verified in HCC clinical samples by tissue microarrays.
RESULTS: The expression of TCF7L2 was upregulated in HCC, and high expression of TCF7L2 was associated with poor prognosis of HCC patients. Overexpression of TCF7L2 promoted the metastasis of HCC in vitro and in vivo, while Knockdown of TCF7L2 showed the opposite effect. Mechanically, TCF7L2 activated neural precursor cell expressed developmentally downregulated protein 9 (NEDD9) transcription by binding to the -1522/-1509 site of the NEDD9 promoter region, thereby increasing the phosphorylation levels of AKT and mTOR. The combination of TCF7L2 and NEDD9 could distinguish the survival of HCC patients.
CONCLUSIONS: This study demonstrated that TCF7L2 promotes HCC metastasis by activating AKT/mTOR pathway in a NEDD9-dependent manner, suggesting that potential of TCF7L2 and NEDD9 as prognostic markers and therapeutic targets for HCC.

Magnesium (Mg) deficiency is associated with increased risk and malignancy in colorectal cancer (CRC), yet the underlying mechanisms remain elusive. Here, we used genomic, proteomic, and phosphoproteomic data to elucidate the impact of Mg deficiency on CRC. Genomic analysis identified 160 genes with higher mutation frequencies in Low-Mg tumors, including key driver genes such as KMT2C and ERBB3. Unexpectedly, initiation driver genes of CRC, such as TP53 and APC, displayed higher mutation frequencies in High-Mg tumors. Additionally, proteomic and phosphoproteomic data indicated that low Mg content in tumors may activate epithelial-mesenchymal transition (EMT) by modulating inflammation or remodeling the phosphoproteome of cancer cells. Notably, we observed a negative correlation between the phosphorylation of DBN1 at S142 (DBN1S142p) and Mg content. A mutation in S142 to D (DBN1S142D) mimicking DBN1S142p upregulated MMP2 and enhanced cell migration, while treatment with MgCl2 reduced DBN1S142p, thereby reversing this phenotype. Mechanistically, Mg2+ attenuated the DBN1-ACTN4 interaction by decreasing DBN1S142p, which in turn enhanced the binding of ACTN4 to F-actin and promoted F-actin polymerization, ultimately reducing MMP2 expression. These findings shed new light on the crucial role of Mg deficiency in CRC progression and suggest that Mg supplementation may be a promising preventive and therapeutic strategy for CRC.

The protein kinase B (Akt) pathway can regulate the growth, proliferation, and metabolism of tumor cells and stem cells through the activation of multiple downstream target genes, thus affecting the development and treatment of a range of diseases. Thioesterase superfamily member 4 (THEM4), a member of the thioesterase superfamily, is one of the Akt kinase-binding proteins. Some studies on the mechanism of cancers and other diseases have shown that THEM4 binds to Akt to regulate its phosphorylation. Initially, THEM4 was considered an endogenous inhibitor of Akt, which can inhibit the phosphorylation of Akt in diseases such as lung cancer, pancreatic cancer, and liver cancer, but subsequently, THEM4 was shown to promote the proliferation of tumor cells by positively regulating Akt activity in breast cancer and nasopharyngeal carcinoma, which contradicts previous findings. Considering these two distinct views, this review summarizes the important roles of THEM4 in the Akt pathway, focusing on THEM4 as an Akt-binding protein and its regulatory relationship with Akt phosphorylation in various diseases, especially cancer. This work provides a better understanding of the roles of THEM4 combined with Akt in the treatment of diseases.
蛋白激酶B（Akt）通路可通过激活下游多个靶基因来调控肿瘤细胞和干细胞的生长、增殖和代谢等，从而影响一系列疾病的发生和治疗。硫酯酶超家族成员4（THEM4）作为硫酯酶超家族成员中的一员，也是Akt激酶的结合蛋白之一。癌症等疾病的机制研究发现THEM4可以与Akt结合从而调控Akt的磷酸化。最初，THEM4被认为是Akt的内源性抑制剂，在肺癌、胰腺癌和肝癌等疾病中抑制Akt的磷酸化。但随后的研究发现，THEM4在乳腺癌和鼻咽癌中通过正向调节Akt活性促进肿瘤细胞的增殖，这与之前的研究结果正好相反。面对这两种截然不同的观点，本文综述了THEM4在Akt通路中的重要作用，重点探讨了THEM4作为一种Akt结合蛋白，在各种疾病（尤其是癌症）中与Akt磷酸化的调控关系。这将有助于更好地了解THEM4联合Akt在疾病治疗中的作用。.