GAPVD1 Promotes the Proliferation of Triple-Negative Breast Cancer Cells by Regulating the ERK/MAPK Signaling Pathway.

BACKGROUND: Triple-Negative Breast Cancer (TNBC) accounts for 15-20% of all breast cancers and approximately 50% of breast cancer deaths. Chemotherapy remains the mainstay of systemic treatment due to the lack of effective therapy targets. Thus, more studies are urgently needed to identify new therapeutic targets in TNBC patients. METHODS: GAPVD1 expression and prognosis value in breast cancer samples were explored in The Cancer Genome Atlas database (TCGA). GAPVD1 knockdown and overexpression TNBC cell lines were constructed. CCK-8 and colony formation assays were performed to detect cell viability. Flow cytometry analysis was performed to detect cell cycle variation. Western blotting was conducted to determine the levels of target genes. Finally, an enrichment analysis of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were performed. RESULTS: GAPVD1 is overexpressed in breast cancer tissues and predicts poor prognosis. In vitro experiments demonstrated that GAPVD1 is correlated with cell proliferation and the cell cycle of TNBC cells. Mechanistically, alteration in GAPVD1 expression was found to be associated with cell cycle-related proteins PCNA, Cyclin A, and the activity of the ERK/MAPK signaling pathway. Consistent with these findings, enrichment analysis of GAPVD1-involving partners and signaling pathways revealed that the cellular biosynthetic process, macromolecule biosynthetic process, and cell cycle signaling are related to GAPVD1. In vivo experiment demonstrated that GAPVD1 inhibition impedes tumor growth and expression of cell cyclerelated proteins. CONCLUSION: Taken together, our results indicate that GAPVD1 may participate in TNBC cell growth by regulating the cell cycle and ERK/MAPK signaling pathway.

Tumor Microenvironment Responsive RNA Drug Delivery Systems: Intelligent Platforms for Sophisticated Release.

Cancer is a significant health concern, increasingly showing insensitivity to traditional treatments, highlighting the urgent need for safer and more practical treatment options. Ribonucleic acid (RNA) gene therapy drugs have demonstrated promising potential in preclinical and clinical trials for antitumor therapy by regulating tumor-related gene expression. However, RNA's poor membrane permeability and stability restrict its effectiveness in entering and being utilized in cells. An appropriate delivery system is crucial for achieving targeted tumor effects. The tumor microenvironment (TME), characterized by acidity, hypoxia, enzyme overexpression, elevated glutathione (GSH) concentration, and excessive reactive oxygen species (ROS), is essential for tumor survival. Furthermore, these distinctive features can also be harnessed to develop intelligent drug delivery systems. Various nanocarriers that respond to the TME have been designed for RNA drug delivery, showing the advantages of tumor targeting and low toxicity. This Review discusses the abnormal changes of components in TME, therapeutic RNAs' roles, underlying mechanisms, and the latest developments in utilizing vectors that respond to microenvironments for treating tumors. We hope it provides insight into creating and optimizing RNA delivery vectors to improve their effectiveness.

Metformin suppresses NFE2L1 pathway activation to inhibit gap junction beta protein expression in NSCLC.

OBJECTIVE: Non-small-cell lung cancer (NSCLC) is a deadly form of cancer that exhibits extensive intercellular communication which contributed to chemoradiotherapy resistance. Recent evidence suggests that arrange of key proteins are involved in lung cancer progression, including gap junction proteins (GJPs). METHODS AND RESULTS: In this study, we examined the expression patterns of GJPs in NSCLC, uncovering that both gap junction protein, beta 2 (GJB2) and gap junction protein, beta 2 (GJB3) are increased in LUAD and LUSC. We observed a correlation between the upregulation of GJB2, GJB3 in clinical samples and a worse prognosis in patients with NSCLC. By examining the mechanics, we additionally discovered that nuclear factor erythroid-2-related factor 1 (NFE2L1) had the capability to enhance the expression of connexin26 and connexin 31 in the NSCLC cell line A549. In addition, the use of metformin was discovered to cause significant downregulation of gap junction protein, betas (GJBs) by limiting the presence of NFE2L1 in the cytoplasm. CONCLUSION: This emphasizes the potential of targeting GJBs as a viable treatment approach for NSCLC patients receiving metformin.

VEGFA/NRP-1/GAPVD1 axis promotes progression and cancer stemness of triple-negative breast cancer by enhancing tumor cell-macrophage crosstalk.

Triple-negative breast cancer (TNBC) has long been considered a major clinical challenge due to its aggressive behavior and poor prognosis. Cancer stem cells (CSCs) are known as the main cells responsible for tumor origination, progression, recurrence and metastasis. Here, we report that M2-type tumor-associated macrophages (TAMs) contribute to cancer stemness in TNBC cells via the secretion of VEGFA. Reciprocally, elevated VEGFA expression by TAM-educated TNBC cells acts as a regulator of macrophage polarization, therefore constitute a feed-back loop between TNBC cells and TAMs. Mechanistically, VEGFA facilitates the CSC phenotype via the NRP-1 receptor and downstream GAPVD1/Wnt/ß-catenin signaling pathway in TNBC cells. Our study underscores the crosstalk between TNBC cells and TAMs mediated by VEGFA and further clarifies the role and underlying mechanisms of the VEGFA/NRP-1/GAPVD1 axis in regulating cancer stemness. We also document an immunosuppressive function of VEGFA in the tumor microenvironment (TME). Therefore, the present study indicates crosstalk between TNBC cells and TAMs induced by VEGFA and provides a potential implication for the combination of immunotherapy and VEGFA-targeted agents in TNBC therapy.

Targeting ENPP1 for cancer immunotherapy: Killing two birds with one stone.

Cancer immunotherapy, particularly with immune checkpoint inhibitors, has revolutionized the paradigm of cancer treatment. Nevertheless, the efficacy of cancer immunotherapy remains limited in most clinical settings due to the lack of a preexisting antitumor T-cell response in tumors. Therefore, the clinical outcomes of cancer immunotherapy must be improved crucially. With increased awareness of the importance of the innate immune response in the recruitment of T cells, as well as the onset and maintenance of the T cell response, great interest has been shown in activating the cGAS-STING signaling pathway to awaken the innate immune response, thereby orchestrating both innate and adaptive immune responses to induce tumor clearance. However, tumor cells have evolved to overexpress ectonucleotide pyrophosphate phosphodiesterase 1 (ENPP1), which degrades the immunotransmitter 2',3'-cGAMP and promotes the production of immune-suppressing adenosine, resulting in inhibition of the anticancer immune response in the tumor microenvironment. Clinically, ENPP1 overexpression is closely associated with poor prognosis in patients with cancer. Conversely, depleting or inhibiting ENPP1 has been verified to elevate extracellular 2',3'-cGAMP levels and inhibit the generation of adenosine, thereby reinvigorating the anticancer immune response for tumor elimination. A variety of ENPP1 inhibitors have recently been developed and have demonstrated significant promise for cancer immunotherapy. In this review, we provide an overview of ENPP1, dissect its immunosuppressive mechanisms, and discuss the development of ENPP1 inhibitors with the potential to further improve the efficacy of cancer immunotherapy.

PLK3 promotes the proneural-mesenchymal transition in glioblastoma via transcriptional regulation of C5AR1.

BACKGROUND: Accumulating evidence suggests that polo-like kinase 3 (PLK3) plays an essential role in tumor cells and induces cell proliferation and may have implications for the prognosis of various cancers. We sought to define the role of PLK3-dependent proneural-mesenchymal transition (PMT) in the glioblastoma (GBM) therapy. METHODS AND RESULTS: We analyzed the expression data for PLK3 by using the TCGA database. PLK3 expression in GBM cell lines was determined by qRT-PCR and Western blotting. PLK3 levels were modulated using Lentivirus infection, and the effects on symptoms, tumor volume, and survival in mice intracranial xenograft models were determined. Irradiation (IR) was performed to induce PMT. PLK3 expression was significantly elevated in mesenchymal subtype GBM and promoted tumor proliferation in GBM. Additionally enriched PLK3 expression could be associated with poor prognosis in GBM patients compared with those who have lower PLK3 expression. Mechanically, PLK3-dependent PMT induced radioresistance in GBM cells via transcriptional regulation of complement C5a receptor 1 (C5AR1). In therapeutic experiments conducted in vitro, targeting PLK3 by using small molecule inhibitor decreased tumor growth and radioresistance of GBM cells both in vitro and in vivo. CONCLUSIONS: PLK3-C5AR1 axis induced PMT thus enhanced radioresistance in GBM and could become a novel potential therapeutic target for GBM.

Dual gatekeepers-modified mesoporous organic silica nanoparticles for synergistic photothermal-chemotherapy of breast cancer.

HYPOTHESIS: Construction of dual gatekeepers-functionalized mesoporous organic silica nanoparticles (MONs) with both physical and chemical mechanisms for modulated drug delivery properties provides one solution to the extracellular stability vs. intracellular high therapeutic efficiency of MONs that hold great potential for clinical translations. EXPERIMENTS: We reported herein facile construction of diselenium-bridged MONs decorated with dual gatekeepers, i.e., azobenzene (Azo)/polydopamine (PDA) for both physical and chemical modulated drug delivery properties. Specifically, Azo can act as a physical barrier to block DOX in the mesoporous structure of MONs for extracellular safe encapsulation. The PDA outer corona serves not only as a chemical barrier with acidic pH-modulated permeability for double insurance of minimized DOX leakage in the extracellular blood circulation but also for inducing a PTT effect for synergistic PTT and chemotherapy of breast cancer. FINDINGS: An optimized formulation, DOX@(MONs-Azo3)@PDA resulted in approximately 1.5 and 2.4 fold lower IC50 values than DOX@(MONs-Azo3) and (MONs-Azo3)@PDA controls in MCF-7 cells, respectively, and further mediated complete tumor eradication in 4T1 tumor-bearing BALB/c mice with insignificant systematic toxicity due to the synergistic PTT and chemotherapy with enhanced therapeutic efficiency.

Comprehensive Analysis of the Expression and Prognosis of chromobox Family Members in Breast Cancer.

BACKGROUND: Chromobox proteins are canonical components of the Polycomb group family and play pivotal roles in several cancers. However, little is known about the function, prognostic value and drug sensitivity of CBX family members in breast cancer. METHODS: In this study we investigated the expression, prognosis value and drug sensitivity of CBX family in breast cancer using the ONCOMINE, GEPIA, Human Protein Atlas and Kaplan-Meier Plotter databases, etc. and preliminary verified the expression of CBX family in breast cancer cell lines by RT-qPCR. RESULTS: We found that the expression levels of CBX1/2/3/4/8 members were elevated in breast cancer tissues compared to adjacent normal breast tissues, while the expression levels of CBX6/7 genes were reduced in breast cancer tissue. In vitro qRT-PCR validated the expression differences of CBX1/2/3/4/8 in breast cancer cell lines. Further analysis showed expression of CBX family members was remarkably correlated with cancer subgroups. As nodal metastasis status increased, the mRNA expression of CBX1/2/3/4/8 members tended to be higher, while CBX6/7 tended to be lower. The expression of CBX1/2/3 was higher in patients with TP53 mutation and CBX6/7 expression tended to be lower in patients with TP53 mutation groups. High transcription levels of CBX2/3 were significantly associated with shorter overall survival in breast cancer patients, while lower expression of CBX4/5/6/7 members was associated with unfavorable overall survival. Moreover, a high mutation rate of CBX gene members (43%) was observed in breast cancer patients, and genetic alterations in CBX genes was associated with poor prognosis. CONCLUSION: Taken together, our results indicated that CBX2/3/6/7/8 could be considered prognostic and therapeutic biomarkers of breast cancer and are worthy of further study.

Interaction of aging and Immunosenescence: New therapeutic targets of aging.

Aging is a natural physiological process, but aging can increase the prevalence and mortality of chronic diseases in the elderly. It involves multiple organs and systems, and an essential aspect of aging is immunosenescence. With the increase of age, the immune system has undergone a series of changes and disorders. These changes have led to a decline in the resistance of the elderly to infection, reduced immunity to vaccines, increased incidence of cancer and autoimmune diseases, and an increased structural prevalence of low-grade inflammation. Moreover, affecting the aging process to a certain extent. This review introduces the changes in the immune system during aging and discusses the consequences and effects of these changes. And its effect on the aging process and the methods and ways of anti-aging were discussed.

Targeting STING for cancer immunotherapy: From mechanisms to translation.

Cancer immunotherapy with immune checkpoint inhibitors has achieved unprecedented success in cancer treatment; However, only a subset of patients achieved clinical benefit from this treatment, underscoring the urgent need to identify new strategies to enhance the clinical efficacy of immune checkpoint inhibitors. Given the essential role of innate immunity in cancer immune surveillance, tremendous effort has been focused on the innate immune pathways that can be pharmacologically modulated to improve the clinical outcome of checkpoint inhibitors. The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway plays essential roles in host defense against cancers. Activation of the cGAS-STING signaling pathway induces the expression of type I interferons and proinflammatory cytokines, culminating in promotion of a robust adaptive antitumor immunity. As part of this innate immune signaling pathway, STING is ubiquitously expressed in immune and nonimmune cells. STING activation has been demonstrated to propagate the cancer immunity cycle, remodel the tumor microenvironment, and ultimately eliminate tumor cells. The immunomodulatory roles of STING enable it to be an appealing target for cancer immunotherapy. As such, STING agonists that are capable of triggering antitumor immune responses have been developed in recent years, and several of them have advanced into clinical trials. In this review, we first give an overview on the STING signaling pathway, then dissect the roles of STING activation in different steps of the cancer immunity cycle and finally discuss the development of STING agonists as well as challenges with STING activation, with the potential to make cancer immunotherapy with STING agonists more effective.

A yes-associated protein 1- Notch1 receptor positive feedback loop promotes breast cancer lung metastasis by attenuating the bone morphogenetic protein 4-SMAD family member 1/5 signaling.

The Notch1 (Notch1 receptor) and yes-associated protein 1 (YAP1) signaling can regulate breast cancer metastasis. This study aimed at investigating whether and how these two signal pathways crosstalk to promote breast cancer lung metastasis. Here, we show that YAP1 expression was positively correlated with Notch1 in breast cancer according to bioinformatics and experimental validation. Mechanistically, YAP1 with TEA domain transcription factors (TEADs) enhanced Jagged1(JAG1)-Notch1 signaling. Meanwhile, Notch1 promoted YAP1 stability in breast cancer cells by inhibiting the ß-TrCP-mediated degradation, thereby, forming a YAP1- JAG1/Notch1 positive feedback loop in breast cancer. Furthermore, YAP1 enhanced the mammosphere formation and stemness of MDA-MB-231 cells by attenuating the inhibition of the BMP4-SMAD1/5 signaling. In vivo, the YAP1- JAG1/Notch1 positive feedback loop promoted the lung colonization of MDA-MB-231 cells. Our data for the first time indicate that the YAP1-Notch1 positive feedback loop promotes lung metastasis of breast cancer by modulating self-renewal and inhibiting the BMP4-SMAD1/5 signaling.

The formation mechanism and homeostasis of extrachromosomal DNA.

Extrachromosomal DNA, referred to as extrachromosomal DNA (ecDNA), was found in most cancers and nearly absent in normal cells. The properties of ecDNA enable tumor cells to be more responsive to various environments. The non-Mendelian genetic mechanism of ecDNA could arouse increasing tumor heterogeneity. Besides, ecDNA would promote tumor invasiveness and provide resistance mechanisms associated with poorer survival consequences. Furthermore, ecDNA could profoundly impact oncogene activation, genome instability, tumor heterogeneity, etc. Consequently, they may offer potential possibilities for tumor diagnosis and therapeutics. We primarily reviewed the classification, several primary formation mechanisms, homeostasis maintenance and frontier progress of ecDNA and late emphasized its fundamental roles in tumorigenesis and put forward some new insights.

MiR-26a-5p regulates proliferation, apoptosis, migration and invasion via inhibiting hydroxysteroid dehydrogenase like-2 in cervical cancer cell.

BACKGROUND: Evidences have indicated that miR-26a-5p regulates the malignant properties of various tumor cells. However, the influences of miR-26a-5p on proliferation, apoptosis and invasion are still vague in the cervical cancer (CC) cells. METHODS: The miRNA microarray and real-time quantitative PCR (RT-qPCR) analysis were utilized to detect the expression of miR-26a-5p in the patients with CC. Kaplan-Meier plotter was performed to evaluate the overall survival (OS) of the patients with CC. The CCK-8, flow cytometry, transwell and wound healing analyses were respectively used to analyze proliferation, migration and invasion in the CC cells. RT-qPCR, western blot and IHC analysis were executed to measure the expression of hydroxysteroid dehydrogenase like-2 (HSDL2) in the patients with CC. Bioinformatics and luciferase reporter assay were carried out to verify the relationship of miR-26a-5p and HSDL2. RESULTS: The expression of miR-26a-5p was downregulated and low expression of miR-26a-5p indicated a poor OS in patients with CC. Overexpression of miR-26a-5p significantly inhibited proliferation, migration and invasion, accelerated apoptosis in the Hela and C33A cells. The expression of HSDL2 was upregulated, and negatively correlated with miR-26a-5p in the patients with CC. HSDL2 was directly targeted by miR-26a-5p and rescue experiments displayed that HSDL2 partially abolished proliferation, apoptosis, migration, and invasion induced by miR-26a-5p in CC cells. CONCLUSIONS: MiR-26a-5p alleviated progression of CC by suppressing proliferation, migration and invasion, promoting apoptosis through downregulating HSDL2.

T-cell immunoglobulin and ITIM domain in cancer immunotherapy: A focus on tumor-infiltrating regulatory T cells.

T-cell immunoglobulin and ITIM domain (TIGIT) is a novel type of immune checkpoint. Importantly, immune checkpoint molecules promote cancer progression by various antitumor suppressive mechanisms. TIGIT is an inhibitory receptor expressed on T cells, natural killer cells, and regulatory T cells that was recently attracted attention as a major emerging target for cancer immunotherapy. Regulatory T cells (Tregs) play crucial roles in immune homeostasis. Specifically, tumor-infiltrating Tregs promote cancer progression by restricting antitumor immunity and supporting tumor immune escape. In this review, we summarized the current understanding on TIGIT and tumor-infiltrating Tregs. Here, we reviewed the latest advances in the understanding of mechanisms causing tumor-infiltrating Tregs abundance to optimize Tregs targeted therapy. Collectively, anti-TIGIT targeting Tregs hold great promise for potent cancer target therapy.

Recent Advances and Next Breakthrough in Immunotherapy for Cancer Treatment.

With the huge therapeutic potential, cancer immunotherapy is expected to become the mainstream of cancer treatment. In the current field of cancer immunotherapy, there are mainly five types. Immune checkpoint blockade therapy is one of the most promising directions. Adoptive cell therapy is an important component of cancer immunotherapy. The therapy with the cancer vaccine is promising cancer immunotherapy capable of cancer prevention. Cytokine therapy is one of the pillars of cancer immunotherapy. Oncolytic immunotherapy is a promising novel component of cancer immunotherapy, which with significantly lower incidence of serious adverse reactions. The recent positive results of many clinical trials with cancer immunotherapy may herald good clinical prospects. But there are still many challenges in the broad implementation of immunotherapy. Such as the immunotherapy cannot act on all tumors, and it has serious adverse effects including but not limited to nonspecific and autoimmunity inflammation. Here, we center on recent progress made within the last 5 years in cancer immunotherapy. And we discuss the theoretical background, as well as the opportunities and challenges of cancer immunotherapy.

Tumor microenvironment based stimuli-responsive CRISPR/Cas delivery systems: A viable platform for interventional approaches.

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) systems have emerged as robust tools in cancer gene therapy due to their simplicity and versatility. Nevertheless, the genome editing efficiency in tumor sites and the clinical applications of CRISPR/Cas have been compromised by non-specific delivery and genotoxicity. Recently, intelligent delivery systems incorporating sensitive materials in response to endogenous stimuli of the tumor microenvironment (TME) have represented viable platforms for tumor-specific genome editing and reduced side effects of CRISPR/Cas. Spurred by this promising direction, this review first introduces the CRISPR/Cas systems widely employed in cancer therapeutic explorations. Various types of CRISPR/Cas delivery systems sensitive to the stimuli in TME and typical dual-/multiple-responsive CRISPR/Cas carriers are further discussed, emphasizing the correlations between sensitive components and spatiotemporal delivery mechanisms. The genome editing efficiencies of CRISPR/Cas-loaded stimuli-responsive carriers are also summarized both in vitro and in vivo. Collectively, stimuli-responsive CRISPR/Cas delivery systems hold great promise for potent cancer gene therapy.

Progress on the role of extrachromosomal DNA in tumor pathogenesis and evolution.

The amplification of oncogenes on extrachromosomal DNA (ecDNA) provides a new mechanism for cancer cells to adapt to the changes in the tumor microenvironment and accelerate tumor evolution. These extrachromosomal elements contain oncogenes, and their chromatin structures are more open than linear chromosomes and therefore have stronger oncogene transcriptional activity. ecDNA always contains enhancer elements, and genes on ecDNA can be reintegrated into the linear genome to regulate the selective expression of genes. ecDNA lacks centromeres, and the inheritance from the parent cell to the daughter cell is uneven. This non-Mendelian genetic mechanism results in the increase of tumor heterogeneity with daughter cells that can gain a competitive advantage through a large number of copies of oncogenes. ecDNA promotes tumor invasiveness and provides a mechanism for drug resistance associated with poorer survival outcomes. Recent studies have demonstrated that the overall proportion of ecDNA in tumors is approximately 40%. In this review, we summarize the current knowledge of ecDNA in the field of tumorigenesis and development.

PDK4 promotes tumorigenesis and cisplatin resistance in lung adenocarcinoma via transcriptional regulation of EPAS1.

The use of cisplatin for the treatment of non-small cell lung cancer has long been constrained by the rapid acquisition of tumor cell chemoresistance. In the present study, we sought to better elucidate the molecular mechanisms underlying this resistance phenotype. To that end, we assessed gene expression patterns in cisplatin-resistant lung adenocarcinoma cells, revealing pyruvate dehydrogenase lipoamide kinase isozyme 4 (PDK4) to be the most up-regulated kinase in resistant cells. We further found PDK4 upregulation to be directly linked with the acquisition of chemoresistance, driving enhanced tumor cell growth in vitro and in vivo. In clinical samples, we also found that PDK4 upregulation was detectable in patients with lung adenocarcinoma and that it was correlated with a poorer prognosis for these patients. From a mechanistic perspective, we further determined that PDK4 was able to promote lung adenocarcinoma cell growth and cisplatin resistance at least in part via regulating endothelial PAS domain-containing protein 1 (EPAS1) expression, thus highlighting PDK4 as a potentially viable therapeutic target in efforts to treat lung adenocarcinoma patients that have become resistant to cisplatin.

The interplay between ATF2 and NEAT1 contributes to lung adenocarcinoma progression.

BACKGROUND: Activating transcription factor 2 (ATF2), a member of the activator protein 1 (AP-1) transcription factor family, has been shown to be involved in the pathobiology of numerous cancers. However, the biological role and mechanism of ATF2 in lung adenocarcinoma (LUAD) remains to be elucidated. METHODS: The expression of ATF2, NEAT1 and miR-26a-5p in LUAD tissues and cell lines was detected by qRT-PCR and western blotting. The interaction between ATF2, NEAT1, and miR-26a-5p was validated by chromatin immunoprecipitation, luciferase reporter assay and RNA immunoprecipitation. Cell proliferation, invasion and tumorigenesis of LUAD cells were analyzed by using CCK8, transwell invasion assay and xenograft tumor model. RESULTS: We confirmed that ATF2 expression was increased in LUAD tissues compared with normal adjacent lung tissues. Functional experiments showed that ATF2 positively regulated cell proliferation and invasion in LUAD cells. Moreover, we identified that NEAT1 expression was increased in LUAD tissues and positively correlated with ATF2 expression. Mechanistically, ATF2 could bind to the promoter of NEAT1 to promote its transcription. Rescue experiments showed that ATF2 exerted its oncogenic function in LUAD, at least, partly through NEAT1 upregulation. In turn, NEAT1 could positively regulate ATF2 expression and form a positive feedback loop in LUAD cells. Furthermore, we demonstrated that NEAT1 positively regulated ATF2 expression via sponging miR-26a-5p. CONCLUSION: ATF2 and NEAT1 form a positive feedback loop mediated by miR-26a-5p and coordinately contribute to LUAD progression.