Targeting the SphK1/S1P/S1PR1 Axis That Links Obesity, Chronic Inflammation, and Breast Cancer Metastasis

Intratumoral mycobiome heterogeneity influences the tumor microenvironment and immunotherapy outcomes in renal cell carcinoma

The intratumoral mycobiome plays a crucial role in the tumor microenvironment, but its impact on renal cell carcinoma (RCC) remains unclear. We collected and quantitatively profiled the intratumoral mycobiome data from 1044 patients with RCC across four international cohorts, of which 466 patients received immunotherapy. Patients were stratified into mycobiota ecology-depauperate and mycobiota ecology-flourishing (MEF) groups based on fungal abundance. The MEF group had worse prognosis, higher fungal diversity, down-regulated lipid catabolism, and exhausted CD8+ T cells. We developed the intratumoral mycobiota signature and intratumoral mycobiota-related genes expression signature, which robustly predicted prognosis and immunotherapy outcomes in RCC and other cancers. Aspergillus tanneri was identified as a potential key fungal species influencing RCC prognosis. Our findings suggest that the intratumoral mycobiome suppresses lipid catabolism and induces T cell exhaustion in RCC.

UPLC-Q-TOF-MS-based unbiased serum metabolomics investigation of cholangiocarcinoma

Objective

Cholangiocarcinoma (CCA) is a highly aggressive malignancy, and early diagnosis remains challenging. Metabolic biomarkers are increasingly recognized as promising tools for the early detection of cancer. However, a comprehensive exploration of metabolic alterations in CCA, especially from a global metabolic perspective, has yet to be fully realized. To identify reliable metabolic markers for the early diagnosis of CCA and to explore its potential pathogenesis through an in-depth analysis of global metabolism.

Methods

Serum samples from 30 CCA patients and 31 healthy individuals were analyzed using an unbiased UPLC-Q-TOF-MS based metabolomics approach. Principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA) were applied to identify potential biomarkers. High-resolution MS/MS and available standards were used to further confirm the identified metabolites. A systematic metabolic pathway analysis was conducted to interpret the biological roles of these biomarkers and explore their relevance to CCA progression.

Results

A total of 25 marker metabolites were identified, including lysophosphatidylcholines (LysoPCs), phosphatidylcholines (PCs), organic acids, sphinganine, and ketoleucine. These metabolites effectively distinguished CCA patients from healthy controls, with an AUC of 0.995 for increased biomarkers and 0.992 for decreased biomarkers in positive mode. In negative mode, the AUC for increased and decreased biomarkers was 0.899 and 0.976, respectively. The metabolic pathway analysis revealed critical biological functions linked to these biomarkers, offering insights into the molecular mechanisms underlying CCA initiation and progression.

Conclusion

This study identifies novel metabolic biomarkers for the early diagnosis of CCA and provides a deeper understanding of the metabolic alterations associated with the disease. These findings could contribute to the development of diagnostic strategies and therapeutic interventions for CCA.

Tumor Necrosis Factor-Alpha and Its Association With Breast Cancer: A Systematic Review

Background

Tumor necrosis factor-alpha (TNF-α) is a pro-inflammatory cytokine implicated in the pathogenesis and progression of various cancers, including breast cancer. Elevated TNF-α levels have been associated with cancer progression, metastasis, and treatment outcomes. This systematic review aimed to synthesize existing evidence on the relationship between TNF-α levels and breast cancer.

Methods

A systematic search of observational studies published from inception to June 2024 was conducted in PubMed, ScienceDirect, Sage Journals, and Google Scholar to identify studies examining TNF-α levels in breast cancer patients compared to healthy controls, as well as its association with metastasis, response to chemotherapy, and survival outcomes. Inclusion criteria were applied to select eligible studies, resulting in nine studies that met the criteria for this review.

Results

Eight eligible studies reported that breast cancer patients exhibited higher TNF-α levels than healthy controls. Two studies indicated that TNF-α levels were elevated in patients with metastatic breast cancer. Additionally, two studies found that patients with higher TNF-α levels tended to have a poorer response to chemotherapy. One study revealed that patients with elevated TNF-α levels had a lower mean survival time.

Conclusions

Elevated TNF-α levels are significantly associated with breast cancer progression, metastasis, and poorer treatment outcomes. These findings underscore the potential of TNF-α as a biomarker for breast cancer prognosis and therapeutic response. Further research is warranted to explore the underlying mechanisms and validate TNF-α as a target for therapeutic intervention in breast cancer management.

S1PR1-biased activation drives the resolution of endothelial dysfunction-associated inflammatory diseases by maintaining endothelial integrity

G protein-coupled sphingosine-1-phosphate receptor 1 (S1PR1), a drug target for inflammatory bowel disease (IBD), enables immune cells to egress from lymph nodes, but the treatment increases the risk of immunosuppression. The functional signaling pathway triggered by S1PR1 activation in endothelial cells and its therapeutic application remains unclear. Here, we showed that S1PR1 is highly expressed in endothelial cells of IBD patients and positively correlated with endothelial markers. Gi-biased agonist-SAR247799 activated S1PR1 and reversed pathology in male mouse and organoid IBD models by protecting the integrity of the endothelial barrier without affecting immune cell egress. Cryo-electron microscopy structure of S1PR1-Gi signaling complex bound to SAR247799 with a resolution of 3.47 Å revealed the recognition mode for the biased ligand. With the efficacy of SAR247799 in treating other endothelial dysfunction-associated inflammatory diseases, our study offers mechanistic insights into the Gi-biased S1PR1 agonist and represents a strategy for endothelial dysfunction-associated disease treatment.

Targeting the tumor immune microenvironment: GPCRs as key regulators in triple-negative breast cancer

Triple-negative breast cancer (TNBC) poses a significant clinical challenge due to its aggressive nature and limited therapeutic options. Recent research underscores the pivotal role of G protein-coupled receptors (GPCRs) in shaping the tumor immune microenvironment (TIME) within TNBC. This review focuses on four principal GPCRs-chemokine receptors, sphingosine-1-phosphate receptors, prostaglandin E2 receptors, and lactate receptors-that have garnered substantial attention in TNBC studies. GPCRs modulate immune cell recruitment, polarization, and function, thereby fostering an immunosuppressive milieu conducive to tumor progression and metastasis. The review examines how alterations in GPCR expression on immune cells influence the pathogenesis and advancement of TNBC. Further, it discusses emerging therapeutic strategies targeting GPCR signaling pathways to remodel the immunosuppressive TIME in TNBC. These insights into GPCR-mediated immune regulation not only deepen our comprehension of TNBC's pathophysiology but also offer promising avenues for developing novel immunotherapies aimed at enhancing clinical outcomes for TNBC patients.

Targeting lipid metabolism of macrophages: A new strategy for tumor therapy

BACKGROUND

Lipid metabolism has been implicated in a variety of normal cellular processes and strongly related to the development of multiple diseases, including tumor. Tumor-associated macrophage (TAM) has emerged as a crucial regulator in tumorigenesis and promising target for tumor treatment.

AIM OF REVIEW

A thorough understanding of TAM lipid metabolism and its value in tumorigenesis may provide new ideas for TAM-based anti-tumor therapy. Key scientific concepts of review: TAMs can be divided into two main types, M1-like TAMs and M2-like TAMs, which play anti-tumor and pro-tumor functions in tumor occurrence and development, respectively. Accumulating evidence has shown that lipid metabolic reprogramming, including fatty acid uptake and utilization, cholesterol expulsion, controls the polarization of TAMs and affects the tumorgenesis. These advances in uncovering the intricacies of lipid metabolism and TAMs have yielded new insights on tumor development and treatment. In this review, we aim to provide an update on the current understanding of the lipid metabolic reprogramming made by TAMs to adapt to the harsh tumor microenvironment (TME). In particular, we emphasize that there is complex lipid metabolism connections between TAMs and distinct tumors, which influences TAM to bias from M1 to M2 phenotype in tumor progression, and ultimately promotes tumor occurrence and development. Finally, we discuss the existing issues on therapeutic strategies by reprogramming TAMs based on lipid metabolism regulation (or increasing the ratio of M1/M2-like TAMs) that could be applied in the future to clinical tumor treatment.

The Use of Biologics for Targeting GPCRs in Metastatic Cancers

A comprehensive review of studies describing the role of G-protein coupled receptor (GPCR) behaviour contributing to metastasis in cancer, and the developments of biotherapeutic drugs towards targeting them, provides a valuable resource toward improving our understanding of the opportunities to effectively target this malignant tumour cell adaptation. Focusing on the five most common metastatic cancers of lung, breast, colorectal, melanoma, and prostate cancer, we highlight well-studied and characterised GPCRs and some less studied receptors that are also implicated in the development of metastatic cancers. Of the approximately 390 GPCRs relevant to therapeutic targeting, as many as 125 of these have been identified to play a role in promoting metastatic disease in these cancer types. GPCR signalling through the well-characterised pathways of chemokine receptors, to emerging data on signalling by orphan receptors, is integral to many aspects of the metastatic phenotype. Despite having detailed information on many receptors and their ligands, there are only thirteen approved therapeutics specifically for metastatic cancer, of which three are small molecules with the remainder including synthetic and non-synthetic peptides or monoclonal antibodies. This review will cover the existing and potential use of monoclonal antibodies, proteins and peptides, and nanobodies in targeting GPCRs for metastatic cancer therapy.

Perilipin2-dependent lipid droplets accumulation promotes metastasis of oral squamous cell carcinoma via epithelial-mesenchymal transition

Emerging evidence shows that lipid metabolic reprogramming plays a vital role in tumor metastasis. The effect and mechanism of fatty acids and lipid droplets (LDs), the core products of lipid metabolism, on the metastasis of oral squamous cell carcinoma (OSCC), need further exploration. In this study, the influence of palmitic acid (PA) and oleic acid (OA) on the migration and invasion ability of OSCC cells was determined by in vitro experiments. Genetic manipulation of PLIN2 was performed to explore its effect on the accumulation of LDs and OSCC metastasis. Possible mechanisms of these biological effects were clarified by detecting the levels of epithelial-mesenchymal transition (EMT) markers and phosphatidylinositol 3-kinase (PI3K) pathway proteins as well as conducting various bioinformatics analyses. The results indicated that PA/OA promoted the migration and invasion of OSCC cells and induced PLIN2-dependent LDs accumulation in vitro. Knockdown of PLIN2 inhibited the LDs accumulation and the migration and invasion of OSCC cells in vitro, while overexpression of PLIN2 enhanced those of OSCC cells in vitro and also promoted the metastasis of OSCC in vivo. Besides, PLIN2 up-regulation activated the PI3K pathway and subsequently enhanced EMT in OSCC cells in vitro. OSCC patients with higher PLIN2 expression possessed poorer prognosis and higher sensitivity to chemotherapy drugs (1S,3 R)-RSL3 and ML-210. In conclusion, PLIN2-dependent LDs accumulation could promote the metastasis of OSCC cells by regulating EMT. PLIN2 might be a potential therapeutic target for OSCC patients, especially those with obesity.

Who is Focusing on Women's Health: A Bibliometric Analysis of Global Research Trends on Overweight in Female Patients with Gynecologic or Breast Cancer

Objective

Obesity has become a significant public health concern, strongly linked to various diseases, particularly gynecologic and breast cancers. This bibliometric review aims to analyze global research trends on overweight women, particularly those with gynecologic and breast cancers, to identify research hotspots, key contributors, and emerging areas of study.

Methods

A comprehensive bibliometric analysis was conducted using the Web of Science Core Collection (WoSCC) database, covering the period from January 2013 to September 2024. Articles were screened and analyzed using tools such as VOSviewer and Biblioshiny platform, with metrics including publication volume, citation analysis, and co-authorship networks. Key areas of focus were global research trends, leading countries, institutions, authors, journals, and keyword analysis.

Results

A total of 1452 publications were analyzed. Research activity on the association between obesity and gynecologic/breast cancer has steadily increased, with the United States leading in publications and citations, followed by China and Italy. Core journals included Breast Cancer Research and Treatment and Gynecologic Oncology. Key research areas identified through keyword analysis include the relationship between body mass index (BMI) and cancer risk, survival rates in cancer patients, physical activity, and the role of adipose tissue inflammation in tumor progression. Emerging topics include extracellular vesicles and cancer-associated fibroblasts.

Conclusion

Global research on the relationship between obesity and female-specific cancers has shown significant growth. The findings highlight BMI, survival, and physical activity as central themes. Future research should explore the molecular mechanisms linking obesity to cancer and evaluate weight loss interventions for cancer prevention and treatment.

Bibliometric and visual analysis of human microbiome-breast cancer interactions: current insights and future directions

The composition of the gut microbiome differs from that of healthy individuals and is closely linked to the progression and development of breast cancer. Recent studies have increasingly examined the relationship between microbial communities and breast cancer. This study analyzed the research landscape of microbiome and breast cancer, focusing on 736 qualified publications from the Web of Science Core Collection (WoSCC). Publications in this field are on the rise, with the United States leading in contributions, followed by China and Italy. Despite this strong output, the centrality value of China in this field is comparatively low at ninth, highlighting a gap between the quantity of research and its global impact. This pattern is repetitively observed in institutional contributions, with a predominance of Western institutes among the top contributors, underscoring a potential research quality gap in China. Keyword analysis reveals that research hotspots are focused on the effect of microbiome on breast cancer pathogenesis and tumor metabolism, with risk factors and metabolic pathways being the most interesting areas. Publications point to a shift toward anti-tumor therapies and personalized medicine, with clusters such as "anti-tumor" and "potential regulatory agent" gaining prominence. Additionally, intratumor bacteria studies have emerged as a new area of significant interest, reflecting a new direction in research. The University of Helsinki and Adlercreutz H are influential institutions and researchers in this field. Current trends in microbiome and breast cancer research indicate a significant shift toward therapeutic applications and personalized medicine. Strengthening international collaborations and focusing on research quality is crucial for advancing microbiome and breast cancer research.

DHRS2-induced SPHK1 downregulation contributes to the cell growth inhibition by Trichothecin in colorectal carcinoma

BACKGROUND

Deregulation of lipid metabolism is one of the most prominent metabolic features in cancer. The activation of sphingolipid metabolic pathways affects the proliferation, invasion, angiogenesis, chemoresistance, and immune escape of tumors, including colorectal cancer (CRC). Dehydrogenase/reductase member 2 (DHRS2), which belongs to the short-chain dehydrogenase/reductase (SDR) family, has been reported to participate in the regulation of lipid metabolism and impact on cancer progression. Trichothecin (TCN) is a sesquiterpenoid metabolite originating from an endophytic fungus of the herbal plant Maytenus hookeri Loes. Studies have shown that TCN exerts a broad-spectrum antitumor activity.

METHODS

We evaluated the proliferative ability of CRC cells by CCK8 and colony formation assays. A metabolite profiling using liquid chromatography coupled with mass spectrometry (LC/MS) was adopted to identify the proximal metabolite changes linked to DHRS2 overexpression. RNA stability assay and RNA immunoprecipitation (RIP) experiments were applied to determine the post-transcriptional regulation of SPHK1 expression by DHRS2. We used flow cytometry to detect changes in cell cycle and cell apoptosis of CRC cells in the absence or presence of TCN.

RESULTS

We demonstrate that DHRS2 hampers the sphingosine kinases 1 (SPHK1)/sphingosine 1-phosphate (S1P) metabolic pathway to inhibit CRC cell growth. DHRS2 directly binds to SPHK1 mRNA to accelerate its degradation in a post-transcriptionally regulatory manner. Moreover, we illustrate that SPHK1 downregulation induced by DHRS2 contributes to TCN-induced growth inhibition of CRC.

CONCLUSIONS

The present study provides a mechanistic connection among metabolic enzymes, metabolites, and the malignant progression of CRC. Moreover, TCN could be developed as a potential pharmacological tool against CRC by the induction of DHRS2 and targeting SPHK1/S1P metabolic pathway.

The identification of key genes and pathways in polycystic ovary syndrome by bioinformatics analysis of next-generation sequencing data

Background

Polycystic ovary syndrome (PCOS) is a reproductive endocrine disorder. The specific molecular mechanism of PCOS remains unclear. The aim of this study was to apply a bioinformatics approach to reveal related pathways or genes involved in the development of PCOS.

Methods

The next-generation sequencing (NGS) dataset GSE199225 was downloaded from the gene expression omnibus (GEO) database and NGS dataset analyzed is obtained from in vitro culture of PCOS patients’ muscle cells and muscle cells of healthy lean control women. Differentially expressed gene (DEG) analysis was performed using DESeq2. The g:Profiler was utilized to analyze the gene ontology (GO) and REACTOME pathways of the differentially expressed genes. A protein–protein interaction (PPI) network was constructed and module analysis was performed using HiPPIE and cytoscape. The miRNA-hub gene regulatory network and TF-hub gene regulatory network were constructed. The hub genes were validated by using receiver operating characteristic (ROC) curve analysis.

Results

We have identified 957 DEG in total, including 478 upregulated genes and 479 downregulated gene. GO terms and REACTOME pathways illustrated that DEG were significantly enriched in regulation of molecular function, developmental process, interferon signaling and platelet activation, signaling, and aggregation. The top 5 upregulated hub genes including HSPA5, PLK1, RIN3, DBN1, and CCDC85B and top 5 downregulated hub genes including DISC1, AR, MTUS2, LYN, and TCF4 might be associated with PCOS. The hub gens of HSPA5 and KMT2A, together with corresponding predicted miRNAs (e.g., hsa-mir-34b-5p and hsa-mir-378a-5p), and HSPA5 and TCF4 together with corresponding predicted TF (e.g., RCOR3 and TEAD4) were found to be significantly correlated with PCOS.

Conclusions

These study uses of bioinformatics analysis of NGS data to obtain hub genes and key signaling pathways related to PCOS and its associated complications. Also provides novel ideas for finding biomarkers and treatment methods for PCOS and its associated complications.

Lipid profiling of RON and DEK-dependent signaling in breast cancer guides discovery of gene networks predictive of poor outcomes

Recurrent and metastatic breast cancer is frequently treatment resistant. A wealth of evidence suggests that reprogrammed lipid metabolism supports cancer recurrence. Overexpression of the RON and DEK oncoproteins in breast cancer is associated with poor outcome. Both proteins promote cancer metastasis in laboratory models, but their influence on lipid metabolite levels remain unknown. To measure RON- and DEK-dependent steady-state lipid metabolite levels, a nuclear magnetic resonance (NMR)-based approach was utilized. The observed differences identified a lipid metabolism-related gene expression signature that is prognostic of overall survival (OS), distant metastasis-free survival (DMFS), post-progression survival (PPS), and recurrence-free survival (RFS) in patients with breast cancer. RON loss led to decreased cholesterol and sphingomyelin levels, whereas DEK loss increased total fatty acid levels and decreased free glycerol levels. Lipid-related genes were then queried to define a signature that predicts poor outcomes for patients with breast cancer patients. Taken together, RON and DEK differentially regulate lipid metabolism in a manner that predicts and may promote breast cancer metastasis and recurrence.

FTY720/Fingolimod mitigates paclitaxel-induced Sparcl1-driven neuropathic pain and breast cancer progression

Paclitaxel is among the most active chemotherapy drugs for the aggressive triple negative breast cancer (TNBC). Unfortunately, it often induces painful peripheral neuropathy (CIPN), a major debilitating side effect. Here we demonstrate that in naive and breast tumor-bearing immunocompetent mice, a clinically relevant dose of FTY720/Fingolimod that targets sphingosine-1-phosphate receptor 1 (S1PR1), alleviated paclitaxel-induced neuropathic pain. FTY720 also significantly attenuated paclitaxel-stimulated glial fibrillary acidic protein (GFAP), a marker for activated astrocytes, and expression of the astrocyte-secreted synaptogenic protein Sparcl1/Hevin, a key regulator of synapse formation. Notably, the formation of excitatory synapses containing VGluT2 in the spinal cord dorsal horn induced by paclitaxel was also inhibited by FTY720 treatment, supporting the involvement of astrocytes and Sparcl1 in CIPN. Furthermore, in this TNBC mouse model that mimics human breast cancer, FTY720 administration also enhanced the anti-tumor effects of paclitaxel, leading to reduced tumor progression and lung metastasis. Taken together, our findings suggest that targeting the S1P/S1PR1 axis with FTY720 is a multipronged approach that holds promise as a therapeutic strategy for alleviating both CIPN and enhancing the efficacy of chemotherapy in TNBC treatment.

Stool Protein Mass Spectrometry Identifies Biomarkers for Early Detection of Diffuse-type Gastric Cancer

There is a high unmet need for early detection approaches for diffuse gastric cancer (DGC). We examined whether the stool proteome of mouse models of gastric cancer (GC) and individuals with hereditary diffuse gastric cancer (HDGC) have utility as biomarkers for early detection. Proteomic mass spectrometry of the stool of a genetically engineered mouse model driven by oncogenic KrasG12D and loss of p53 and Cdh1 in gastric parietal cells [known as Triple Conditional (TCON) mice] identified differentially abundant proteins compared with littermate controls. Immunoblot assays validated a panel of proteins, including actinin alpha 4 (ACTN4), N-acylsphingosine amidohydrolase 2 (ASAH2), dipeptidyl peptidase 4 (DPP4), and valosin-containing protein (VCP), as enriched in TCON stool compared with littermate control stool. Immunofluorescence analysis of these proteins in TCON stomach sections revealed increased protein expression compared with littermate controls. Proteomic mass spectrometry of stool obtained from patients with HDGC with CDH1 mutations identified increased expression of ASAH2, DPP4, VCP, lactotransferrin (LTF), and tropomyosin-2 relative to stool from healthy sex- and age-matched donors. Chemical inhibition of ASAH2 using C6 urea ceramide was toxic to GC cell lines and GC patient-derived organoids. This toxicity was reversed by adding downstream products of the S1P synthesis pathway, which suggested a dependency on ASAH2 activity in GC. An exploratory analysis of the HDGC stool microbiome identified features that correlated with patient tumors. Herein, we provide evidence supporting the potential of analyzing stool biomarkers for the early detection of DGC. Prevention Relevance: This study highlights a novel panel of stool protein biomarkers that correlate with the presence of DGC and has potential use as early detection to improve clinical outcomes.

Self-activating chitosan-based nanoparticles for sphingosin-1 phosphate modulator delivery and selective tumor therapy

This study reports on the design and synthesis of hypoxia responsive nanoparticles (HRNPs) composed of methoxy polyethylene glycol-4,4 dicarboxylic azolinker-chitosan (mPEG-Azo-chitosan) as ideal drug delivery platform for Fingolimod (FTY720, F) delivery to achieve selective and highly enhanced TNBC therapy in vivo. Herein, HRNPs with an average size of 49.86 nm and a zeta potential of +3.22 mV were synthetized, which after PEG shedding can shift into a more positively-charged NPs (+30.3 mV), possessing self-activation ability under hypoxia situation in vitro, 2D and 3D culture. Treatment with lower doses of HRNPs@F significantly reduced MDA-MB-231 microtumor size to 15 %, induced apoptosis by 88 % within 72 h and reduced highly-proliferative 4 T1 tumor weight by 87.66 % vs. ∼30 % for Fingolimod compared to the untreated controls. To the best of our knowledge, this is the first record for development of hypoxia-responsive chitosan-based NPs with desirable physicochemical properties, and selective self-activation potential to generate highly-charged nanosized tumor-penetrating chitosan NPs. This formulation is capable of localized delivery of Fingolimod to the tumor core, minimizing its side effects while boosting its anti-tumor potential for eradication of TNBC solid tumors.

Superparamagnetic iron oxide nanoparticle regulates microbiota-gut-inner ear axis for hearing protection

Noise-induced hearing loss (NIHL) is a highly prevalent form of sensorineural hearing damage that has significant negative effects on individuals of all ages and there are no effective drugs approved by the US Food and Drug Administration. In this study, we unveil the potential of superparamagnetic iron oxide nanoparticle assembly (SPIOCA) to reshape the dysbiosis of gut microbiota for treating NIHL. This modulation inhibits intestinal inflammation and oxidative stress responses, protecting the integrity of the intestinal barrier. Consequently, it reduces the transportation of pathogens and inflammatory factors from the bloodstream to the cochlea. Additionally, gut microbiota-modulated SPIOCA-induced metabolic reprogramming in the gut-inner ear axis mainly depends on the regulation of the sphingolipid metabolic pathway, which further contributes to the restoration of hearing function. Our study confirms the role of the microbiota-gut-inner ear axis in NIHL and provides a novel alternative for the treatment of NIHL and other microbiota dysbiosis-related diseases.

Macrophages and tumor-associated macrophages in the senescent microenvironment: From immunosuppressive TME to targeted tumor therapy

In-depth studies of the tumor microenvironment (TME) have helped to elucidate its cancer-promoting mechanisms and inherent characteristics. Cellular senescence, which acts as a response to injury and can the release of senescence-associated secretory phenotypes (SASPs). These SASPs release various cytokines, chemokines, and growth factors, remodeling the TME. This continual development of a senescent environment could be associated with chronic inflammation and immunosuppressive TME. Additionally, SASPs could influence the phenotype and function of macrophages, leading to the recruitment of tumor-associated macrophages (TAMs). This contributes to tumor proliferation and metastasis in the senescent microenvironment, working in tandem with immune regulation, angiogenesis, and therapeutic resistance. This comprehensive review covers the evolving nature of the senescent microenvironment, macrophages, and TAMs in tumor development. We also explored the links between chronic inflammation, immunosuppressive TME, cellular senescence, and macrophages. Moreover, we compiled various tumor-specific treatment strategies centered on cellular senescence and the current challenges in cellular senescence research. This study aimed to clarify the mechanism of macrophages and the senescent microenvironment in tumor progression and advance the development of targeted tumor therapies.

Celastrol inhibits angiogenesis and the biological processes of MDA-MB-231 cells via the DEGS1/S1P signaling pathway

Celastrol (Cel) shows potent antitumor activity in various experimental models. This study examined the relationship between Cel's antivascular and antitumor effects and sphingolipids. CCK-8 assay, transwell assay, Matrigel, PCR-array/RT-PCR/western blotting/immunohistochemistry assay, ELISA and HE staining were used to detect cell proliferation, migration and invasion, adhesion and angiogenesis, mRNA and protein expression, S1P production and tumor morphology. The results showed that Cel could inhibit proliferation, migration or invasion, adhesion and angiogenesis of human umbilical vein endothelial cells (HUVECs) and MDA-MB-231 cells by downregulating the expression of degenerative spermatocyte homolog 1 (DEGS1). Transfection experiments showed that downregulation of DEGS1 inhibited the above processes and sphingosine-1-phosphate (S1P) production of HUVECs and MDA-MB-231 cells, while upregulation of DEGS1 had the opposite effects. Coculture experiments showed that HUVECs could promote proliferation, migration and invasion of MDA-MB-231 cells through S1P/sphingosine-1-phosphate receptor (S1PR) signaling pathway, while Cel inhibited these processes in MDA-MB-231 cells induced by HUVECs. Animal experiments showed that Cel could inhibit tumor growth in nude mice. Western blotting, immunohistochemistry and ELISA assay showed that Cel downregulated the expression of DEGS1, CD146, S1PR1-3 and S1P production. These data confirm that DEGS1/S1P signaling pathway may be related to the antivascular and antitumor effects of cel.

TNF-Related Apoptosis-Inducing Ligand: Non-Apoptotic Signalling

TNF-related apoptosis-inducing ligand (TRAIL or Apo2 or TNFSF10) belongs to the TNF superfamily. When bound to its agonistic receptors, TRAIL can induce apoptosis in tumour cells, while sparing healthy cells. Over the last three decades, this tumour selectivity has prompted many studies aiming at evaluating the anti-tumoral potential of TRAIL or its derivatives. Although most of these attempts have failed, so far, novel formulations are still being evaluated. However, emerging evidence indicates that TRAIL can also trigger a non-canonical signal transduction pathway that is likely to be detrimental for its use in oncology. Likewise, an increasing number of studies suggest that in some circumstances TRAIL can induce, via Death receptor 5 (DR5), tumour cell motility, potentially leading to and contributing to tumour metastasis. While the pro-apoptotic signal transduction machinery of TRAIL is well known from a mechanistic point of view, that of the non-canonical pathway is less understood. In this study, we the current state of knowledge of TRAIL non-canonical signalling.

Targeting Sphingosine-1-Phosphate Signaling in Breast Cancer

In recent years, newly emerging therapies, such as immune checkpoint inhibitors and antibody-drug conjugates, have further improved outcomes for breast cancer patients. However, recurrent and metastatic breast cancer often eventually develops resistance to these drugs, and cure is still rare. As such, the development of new therapies for refractory breast cancer that differ from conventional mechanisms of action is necessary. Sphingosine-1-phosphate (S1P) is a key molecule with a variety of bioactive activities, including involvement in cancer cell proliferation, invasion, and metastasis. S1P also contributes to the formation of the cancer microenvironment by inducing surrounding vascular- and lymph-angiogenesis and regulating the immune system. In this article, we outline the basic mechanism of action of S1P, summarize previous findings on the function of S1P in cancer cells and the cancer microenvironment, and discuss the clinical significance of S1P in breast cancer and the therapeutic potential of targeting S1P signaling.

Targeting the SPHK1/S1P/S1PR2 axis ameliorates GH-secreted pituitary adenoma progression

BACKGROUND

Growth hormone-secreted pituitary adenoma (GHPA) is a prominent subtype of pituitary adenoma (PA) associated with progressive somatic disfigurement, various complications, and elevated mortality rates. Existing treatment options have limited efficacy, highlighting the urgent need for novel pharmacological interventions. Previous studies have revealed that sphingosine kinase 1 (SphK1)/sphingosine-1-phosphate (S1P)/S1P receptors (S1PRs) signalling have critical roles in the tumour microenvironment, but their role in GHPA remains unclear.

METHODS

We performed integrative analyses including bioinformatics analyses, functional studies, and clinical validation to investigate the pathological roles of SPHK1/S1P and evaluated the effectiveness of the S1P receptor 2 (S1PR2) inhibitor JTE-013 in GHPA treatment.

RESULTS

SPHK1/S1P signalling is abnormally expressed in patients with GHPA. Knockdown of SPHK1 suppresses S1P-mediated cell proliferation in GH3 Cells. Mechanistically, S1P inhibits apoptosis and autophagy while promoting the secretion of Growth Hormone (GH) by binding to the S1P receptor subtype 2 (S1PR2) in GH3 cells. Moreover, the function of S1PR2 in GH3 cells is mediated by the downstream Akt-Creb pathway. We then identify the S1PR2 as a novel target for therapeutic intervention in GHPA. Systemic administration of the potent and selective S1PR2 antagonist, JTE-013, significantly reduces both tumour size and GH secretion. Importantly, we identify preoperative serum S1P levels as a biomarker predicting poor prognosis in GHPA patients at follow-up.

CONCLUSION

Our study shows that blocking SPHK1/S1P/S1PR2 axis can ameliorate the progression of GHPA, providing evidence of a promising therapeutic target for GHPA.

Inhibition of sphingosine kinase 1 attenuates LPS-induced acute lung injury by suppressing endothelial cell pyroptosis

Acute lung injury (ALI) is a frequent complication of sepsis, with pyroptosis playing a pivotal role. Analysis of Gene Expression Omnibus (GEO) mouse sepsis datasets revealed the upregulation of sphingosine kinase 1 (SphK1) in septic mouse lung tissues, which was validated in lipopolysaccharide (LPS)-treated mice. Therefore, this study aimed to explore the potential role and underlying mechanisms of SphK1, the primary kinase responsible for catalyzing the formation of the bioactive lipid sphingosine-1-phosphat, in sepsis development. Mice received an intraperitoneal injection of SphK1 inhibitor prior to LPS administration. Mouse lung vascular endothelial cells (MLVECs) were exposed to LPS and SphK1 inhibitor. The SphK1 inhibitor mitigated ALI, as evidenced by hematoxylin and eosin (H&E) staining and the wet-to-dry (W/D) weight ratio and reduced Evans blue dye leakage. Furthermore, the SphK1 inhibitor inhibited the activation of the NOD-like receptor protein 3 inflammasome and the subsequent induction of pyroptosis both in vivo and in vitro. Intriguingly, using co-immunoprecipitation (Co-IP) combined with mass spectrometry, our findings revealed that SphK1 associates with pyruvate kinase M2 (PKM2), facilitating PKM2 phosphorylation and its nuclear translocation. TEPP-46, which has the ability to stabilize PKM2 and inhibit the phosphorylation and nuclear translocation of PKM2, markedly reduced the expression of pyroptosis-associated markers and alleviated lung injury. Concludingly, our results suggest that targeting SphK1 is a promising therapeutic strategy for ALI.

Tumor-Derived RAB21+ABHD12+ sEVs Drive the Premetastatic Microenvironment in the Lung

Tumor metastasis is a spatial and temporal process that starts with remodeling to generate a proper premetastatic niche in a distant tissue. Infiltration of immunosuppressive macrophages is one of the notable characteristics in the premetastatic niche, which is a fundamental requirement for primary tumor metastasis. Here, we demonstrated that small extracellular vesicles (sEV) carrying RAB21 homed to lung macrophages and interacted with integrin-β1 on macrophages. ABHD12 expression was high in lung metastatic tumors and was mostly expressed by macrophages. Head and neck squamous cell carcinoma (HNSCC)-derived sEVs carrying ABHD12-polarized macrophages toward an immunosuppressive phenotype, driving premetastatic niche formation, which facilitated lung metastasis. ABHD12 additionally upregulated S1PR1 by activating the AKT-FoxO1 pathway in macrophages, and significantly enhanced antitumor responses were observed in tumor models treated with agents targeting both S1PR1 and PD-1. Collectively, our study suggests that RAB21+ABHD12+ sEVs derived from HNSCC cells contribute to the formation of the immunosuppressive microenvironment in the premetastatic niche and are a potential therapeutic target for enhancing the antitumor efficacy of anti-PD-1 therapy.

Roles of exosomes in immunotherapy for solid cancers

Although immunotherapy has made breakthrough progress, its efficacy in solid tumours remains unsatisfactory. Exosomes are the main type of extracellular vesicles that can deliver various intracellular molecules to adjacent or distant cells and organs, mediating various biological functions. Studies have found that exosomes can both activate the immune system and inhibit the immune system. The antigen and major histocompatibility complex (MHC) carried in exosomes make it possible to develop them as anticancer vaccines. Exosomes derived from blood, urine, saliva and cerebrospinal fluid can be used as ideal biomarkers in cancer diagnosis and prognosis. In recent years, exosome-based therapy has made great progress in the fields of drug transportation and immunotherapy. Here, we review the composition and sources of exosomes in the solid cancer immune microenvironment and further elaborate on the potential mechanisms and pathways by which exosomes influence immunotherapy for solid cancers. Moreover, we summarize the potential clinical application prospects of engineered exosomes and exosome vaccines in immunotherapy for solid cancers. Eventually, these findings may open up avenues for determining the potential of exosomes for diagnosis, treatment, and prognosis in solid cancer immunotherapy.

The lipid metabolism remodeling: A hurdle in breast cancer therapy

Lipids, as one of the three primary energy sources, provide energy for all cellular life activities. Lipids are also known to be involved in the formation of cell membranes and play an important role as signaling molecules in the intracellular and microenvironment. Tumor cells actively or passively remodel lipid metabolism, using the function of lipids in various important cellular life activities to evade therapeutic attack. Breast cancer has become the leading cause of cancer-related deaths in women, which is partly due to therapeutic resistance. It is necessary to fully elucidate the formation and mechanisms of chemoresistance to improve breast cancer patient survival rates. Altered lipid metabolism has been observed in breast cancer with therapeutic resistance, indicating that targeting lipid reprogramming is a promising anticancer strategy.

SPHK1/S1P/S1PR pathway promotes the progression of peritoneal fibrosis by mesothelial-mesenchymal transition

Long-term exposure to non-physiologically compatible dialysate inevitably leads to peritoneal fibrosis (PF) in patients undergoing peritoneal dialysis (PD), and there is no effective prevention or treatment for PF. Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid produced after catalysis by sphingosine kinase (SPHK) 1/2 and activates signals through the S1P receptor (S1PR) via autocrine or paracrine. However, the role of SPHK1/S1P/S1PR signaling has never been elucidated in PF. In our research, we investigated S1P levels in peritoneal effluents and demonstrated the role of SPHK1/S1P/S1PR pathway in peritoneal fibrosis. It was found that S1P levels in peritoneal effluents were positively correlated with D/P Cr (r = 0.724, p < .001) and negatively correlated with 4 h ultrafiltration volume (r = -0.457, p < .001). S1PR1 and S1PR3 on peritoneal cells were increased after high glucose exposure in vivo and in vitro. Fingolimod was applied to suppress S1P/S1PR pathway. Fingolimod restored mouse peritoneal function by reducing interstitial hyperplasia, maintaining ultrafiltration volume, reducing peritoneal transport solute rate, and mitigating the protein expression changes of fibronectin, vimentin, α-SMA, and E-cadherin induced by PD and S1P. Fingolimod preserved the morphology of the human peritoneal mesothelial cells, MeT-5A, and moderated the mesothelial-mesenchymal transition (MMT) process. We further delineated that SPHK1 was elevated in peritoneal cells after high glucose exposure and suppression of SPHK1 in MeT-5A cells reduced S1P release. Overexpression of SPHK1 in MeT-5A cells increased S1P levels in the supernatant and fostered the MMT process. PF-543 treatment, targeting SPHK1, alleviated deterioration of mouse peritoneal function. In conclusion, S1P levels in peritoneal effluent were correlated with the deterioration of peritoneal function. SPHK1/S1P/S1PR pathway played an important role in PF.

Lipids as mediators of cancer progression and metastasis

Metastasis formation is a complex process, involving multiple crucial steps, which are controlled by different regulatory mechanisms. In this context, the contribution of cancer metabolism to the metastatic cascade is being increasingly recognized. This Review focuses on changes in lipid metabolism that contribute to metastasis formation in solid tumors. We discuss the molecular mechanisms by which lipids induce a pro-metastatic phenotype and explore the role of lipids in response to oxidative stress and as signaling molecules. Finally, we reflect on potential avenues to target lipid metabolism to improve the treatment of metastatic cancers.

A comprehensive multiomics approach reveals that high levels of sphingolipids in cardiac cachexia adipose tissue are associated with inflammatory and fibrotic changes

Cardiac cachexia is a deadly consequence of advanced heart failure that is characterised by the dysregulation of adipose tissue homeostasis. Once cachexia occurs with heart failure, it prevents the normal treatment of heart failure and increases the risk of death. Targeting adipose tissue is an important approach to treating cardiac cachexia, but the pathogenic mechanisms are still unknown, and there are no effective therapies available. Transcriptomics, metabolomics, and lipidomics were used to examine the underlying mechanisms of cardiac cachexia. Transcriptomics investigation of cardiac cachexia adipose tissue revealed that genes involved in fibrosis and monocyte/macrophage migration were increased and strongly interacted. The ECM-receptor interaction pathway was primarily enriched, as shown by KEGG enrichment analysis. In addition, gene set enrichment analysis revealed that monocyte chemotaxis/macrophage migration and fibrosis gene sets were upregulated in cardiac cachexia. Metabolomics enrichment analysis demonstrated that the sphingolipid signalling pathway is important for adipose tissue remodelling in cardiac cachexia. Lipidomics analysis showed that the adipose tissue of rats with cardiac cachexia had higher levels of sphingolipids, including Cer and S1P. Moreover, combined multiomics analysis suggested that the sphingolipid metabolic pathway was associated with inflammatory-fibrotic changes in adipose tissue. Finally, the key indicators were validated by experiments. In conclusion, this study described a mechanism by which the sphingolipid signalling pathway was involved in adipose tissue remodelling by inducing inflammation and fat fibrosis in cardiac cachexia.

Sphingolipids in mitochondria-from function to disease

Sphingolipids are not only structural components of cellular membranes but also play vital roles in cell signaling and modulation of cellular processes. Within mitochondria, sphingolipids exert diverse effects on mitochondrial dynamics, energy metabolism, oxidative stress, and cell death pathways. In this review, we summarize literature addressing the crucial role of sphingolipids in mitochondria, highlighting their impact on mitochondrial dynamics, cellular bioenergetics, and important cell processes including apoptosis and mitophagy.

Dietary fat and lipid metabolism in the tumor microenvironment

Metabolic reprogramming has been considered a core hallmark of cancer, in which excessive accumulation of lipids promote cancer initiation, progression and metastasis. Lipid metabolism often includes the digestion and absorption of dietary fat, and the ways in which cancer cells utilize lipids are often influenced by the complex interactions within the tumor microenvironment. Among multiple cancer risk factors, obesity has a positive association with multiple cancer types, while diets like calorie restriction and fasting improve health and delay cancer. Impact of these diets on tumorigenesis or cancer prevention are generally studied on cancer cells, despite heterogeneity of the tumor microenvironment. Cancer cells regularly interact with these heterogeneous microenvironmental components, including immune and stromal cells, to promote cancer progression and metastasis, and there is an intricate metabolic crosstalk between these compartments. Here, we focus on discussing fat metabolism and response to dietary fat in the tumor microenvironment, focusing on both immune and stromal components and shedding light on therapeutic strategies surrounding lipid metabolic and signaling pathways.

Sphingosine 1-phosphate signaling during infection and immunity

Sphingolipids are essential components of all eukaryotic membranes. The bioactive sphingolipid molecule, Sphingosine 1-Phosphate (S1P), regulates various important biological functions. This review aims to provide a comprehensive overview of the role of S1P signaling pathway in various immune cell functions under different pathophysiological conditions including bacterial and viral infections, autoimmune disorders, inflammation, and cancer. We covered the aspects of S1P pathways in NOD/TLR pathways, bacterial and viral infections, autoimmune disorders, and tumor immunology. This implies that targeting S1P signaling can be used as a strategy to block these pathologies. Our current understanding of targeting various components of S1P signaling for therapeutic purposes and the present status of S1P pathway inhibitors or modulators in disease conditions where the host immune system plays a pivotal role is the primary focus of this review.

The Metabolomic Characteristics and Dysregulation of Fatty Acid Esters of Hydroxy Fatty Acids in Breast Cancer

Lipid reprogramming metabolism is crucial for supporting tumor growth in breast cancer and investigating potential tumor biomarkers. Fatty acid esters of hydroxy fatty acids (FAHFAs) are a class of endogenous lipid metabolites with anti-diabetic and anti-inflammatory properties that have been discovered in recent years. Our previous targeted analysis of sera from breast cancer patients revealed a significant down-regulation of several FAHFAs. In this study, we aimed to further explore the relationship between FAHFAs and breast cancer by employing chemical isotope labeling combined with liquid chromatography-mass spectrometry (CIL-LC-MS) for profiling of FAHFAs in tumors and adjacent normal tissues from breast cancer patients. Statistical analysis identified 13 altered isomers in breast cancer. These isomers showed the potential to distinguish breast cancer tissues with an area under the curve (AUC) value above 0.9 in a multivariate receiver operating curve model. Furthermore, the observation of up-regulated 9-oleic acid ester of hydroxy stearic acid (9-OAHSA) and down-regulated 9-hydroxystearic acid (9-HSA) in tumors suggests that breast cancer shares similarities with colorectal cancer, and their potential mechanism is to attenuate the effects of pro-apoptotic 9-HSA by enhancing the synthesis of FAHFAs, thereby promoting tumor survival and progression through this buffering system.

Cellular and molecular characteristics of the premetastatic niches

The premetastatic niches (PMN) formed by primary tumor-derived molecules regulate distant organs and tissues to further favor tumor colonization. Targeted PMN therapy may prevent tumor metastasis in the early stages, which is becoming increasingly important. At present, there is a lack of in-depth understanding of the cellular and molecular characteristics of the PMN. Here, we summarize current research advances on the cellular and molecular characteristics of the PMN. We emphasize that PMN intervention is a potential therapeutic strategy for early prevention of tumor metastasis, which provides a promising basis for future research and clinical application.

Metabolic impact of polyphenol-rich aronia fruit juice mediated by inflammation status of gut microbiome donors in humanized mouse model

Background

The Aronia melanocarpa fruit is emerging as a health food owing to its high polyphenolic content and associated antioxidant activity. Antioxidant-rich foods, such as Aronia fruit, may counter inflammatory stimuli and positively modulate the gut microbiome. However, a comprehensive study characterizing the impact of Aronia fruit supplementation has not been completed. Therefore, we completed analyses measuring the metabolic, microbial, and inflammatory effects of a diet supplemented with Aronia fruit juice.

Method

Humanized mice were generated by colonizing gnotobiotic mice with microbiomes from human donors presenting disparate inflammation levels. Blood and fecal samples were collected throughout the course of an 8-week dietary intervention with either Aronia juice or a carbohydrate-matched beverage alone (2 weeks) or in combination with a high-fat diet to induce inflammation (6 weeks). Samples were analyzed using 16S rRNA gene sequencing (stool) and liquid chromatography-mass spectrometry (serum).

Results

We demonstrated transfer of microbiome composition and diversity and metabolic characteristics from humans with low and high inflammation levels to second-generation humanized mice. Aronia supplementation provided robust protection against high-fat diet induced metabolic and microbiome changes that were dependent in part on microbiome donor. Aronia induced increases in bacteria of the Eggerthellaceae genus (7-fold) which aligns with its known ability to metabolize (poly)phenols and in phosphatidylcholine metabolites which are consistent with improved gut barrier function. The gut microbiome from a low inflammation phenotype donor provided protection against high-fat diet induced loss of microbiome β-diversity and global metabolomic shifts compared to that from the high inflammation donor.

Conclusion

These metabolic changes elucidate pathway-specific drivers of reduced inflammation stemming from both Aronia and the gut microbiota.

Fingolimod Modulates the Gene Expression of Proteins Engaged in Inflammation and Amyloid-Beta Metabolism and Improves Exploratory and Anxiety-Like Behavior in Obese Mice

Obesity is considered a risk factor for type 2 diabetes mellitus, which has become one of the most important health problems, and is also linked with memory and executive function decline. Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid that regulates cell death/survival and the inflammatory response via its specific receptors (S1PRs). Since the role of S1P and S1PRs in obesity is rather obscure, we examined the effect of fingolimod (an S1PR modulator) on the expression profile of genes encoding S1PRs, sphingosine kinase 1 (Sphk1), proteins engaged in amyloid-beta (Aβ) generation (ADAM10, BACE1, PSEN2), GSK3β, proapoptotic Bax, and proinflammatory cytokines in the cortex and hippocampus of obese/prediabetic mouse brains. In addition, we observed behavioral changes. Our results revealed significantly elevated mRNA levels of Bace1, Psen2, Gsk3b, Sphk1, Bax, and proinflammatory cytokines, which were accompanied by downregulation of S1pr1 and sirtuin 1 in obese mice. Moreover, locomotor activity, spatially guided exploratory behavior, and object recognition were impaired. Simultaneously, fingolimod reversed alterations in the expressions of the cytokines, Bace1, Psen2, and Gsk3b that occurred in the brain, elevated S1pr3 mRNA levels, restored normal cognition-related behavior patterns, and exerted anxiolytic effects. The improvement in episodic and recognition memory observed in this animal model of obesity may suggest a beneficial effect of fingolimod on central nervous system function.

Sphingosine kinase 1 regulates lipid metabolism to promote progression of kidney renal clear cell carcinoma

PURPOSE

To detect the expression of sphingosine kinase 1 (SPHK1) in clear cell renal cell carcinoma (ccRCC) and explore its biological role in the occurrence and development of ccRCC through regulation of fatty acid metabolism.

METHODS

Using the Cancer Genome Atlas database, SPHK1 expression and its clinical significance were detected in clear cell renal cell carcinoma. Immunohistochemistry was performed to detect SPHK1 expression in RCC samples in our hospital. The connection between the SPHK1 levels and clinicopathological features of patients was assessed. Nile Red was used to detect fatty acids in cells. Cell Counting Kit-8 and 5-ethynyl-2'-deoxyuridine assays were performed to determine the effect of SPHK1 on renal cell viability and proliferation, respectively. Additionally, the effects of SPHK1 on the proliferation and metastasis of ccRCC were studied using wound healing and Transwell assays. Fatty acids were added exogenously in recovery experiments and western blotting was performed to determine the effect of SPHK1 on fatty acid metabolism in ccRCC. Finally, the effects of SPHK1 on tumor growth were investigated in a xenograft model.

RESULTS

Bioinformatics analysis revealed that SPHK1 expression was upregulated in kidney RCC. OverSPHK1 expression was associated with poor prognosis for ccRCC patients. High SPHK1 expression was detected in human ccRCC. SPHK1 expression was related to clinicopathological features, such as tumor size and Furman grade. Additionally, cell proliferation, migration, and invasion were inhibited in ccRCC cells with low SPHK1 expression. In rescue experiments, proliferation, migration, and invasion were restored. In vivo, reduced SPHK1 levels correlated with lower expression of fatty acid synthase, stearoyl-CoA desaturase 1, and acetyl CoA carboxylase, and slowed tumor growth.

CONCLUSIONS

SPHK1 is abnormally overexpressed in human ccRCC. Patients with ccRCC may benefit from treatments that target SPHK1, which may also serve as a prognostic indicator.

The role of sphingosine-1-phosphate in the gut mucosal microenvironment and inflammatory bowel diseases

Sphingosine-1-phosphate (S1P), a type of bioactive sphingolipid, can regulate various cellular functions of distinct cell types in the human body. S1P is generated intracellularly by the catalysis of sphingosine kinase 1/2 (SphK1/2). S1P is transferred to the extracellular environment via the S1P transporter, binds to cellular S1P receptors (S1PRs) and subsequently activates S1P-S1PR downstream signaling. Dysbiosis of the intestinal microbiota, immune dysregulation and damage to epithelial barriers are associated with inflammatory bowel disease (IBD). Generally, S1P mainly exerts a proinflammatory effect by binding to S1PR1 on lymphocytes to facilitate lymphocyte migration to inflamed tissues, and increased S1P was found in the intestinal mucosa of IBD patients. Notably, there is an interaction between the distribution of gut bacteria and SphK-S1P signaling in the intestinal epithelium. S1P-S1PR signaling can also regulate the functions of intestinal epithelial cells (IECs) in mucosa, including cell proliferation and apoptosis. Additionally, increased S1P in immune cells of the lamina propria aggravates the inflammatory response by increasing the production of proinflammatory cytokines. Several novel drugs targeted at S1PRs have recently been used for IBD treatment. This review provides an overview of the S1P-S1PR signaling pathway and, in particular, summarizes the various roles of S1P in the gut mucosal microenvironment to deeply explore the function of S1P-S1PR signaling during intestinal inflammation and, more importantly, to identify potential therapeutic targets for IBD in the SphK-S1P-S1PR axis.

Engineered Lipidic Nanomaterials Inspired by Sphingomyelin Metabolism for Cancer Therapy

Sphingomyelin (SM) and its metabolites are crucial regulators of tumor cell growth, differentiation, senescence, and programmed cell death. With the rise in lipid-based nanomaterials, engineered lipidic nanomaterials inspired by SM metabolism, corresponding lipid targeting, and signaling activation have made fascinating advances in cancer therapeutic processes. In this review, we first described the specific pathways of SM metabolism and the roles of their associated bioactive molecules in mediating cell survival or death. We next summarized the advantages and specific applications of SM metabolism-based lipidic nanomaterials in specific cancer therapies. Finally, we discussed the challenges and perspectives of this emerging and promising SM metabolism-based nanomaterials research area.

Chicoric acid ameliorates palmitate-induced sphingosine 1-phosphate signaling pathway in the PBMCs of patients with newly diagnosed type 2 diabetes

Objective

Sphingosine 1-phosphate (S1P) signaling pathway is involved in the pathogenesis of type 2 diabetes (T2D). So, targeting S1P signaling pathway could be considered as potential therapeutic target for T2D. The aim of this study was to investigate the effects of palmitate and chicoric acid (CA) on S1P signaling pathway in peripheral blood mononuclear cells (PBMCs) from newly diagnosed patients with T2D.

Materials and methods

20 newly diagnosed patients with T2D, aged 40-60 years, were enrolled in the study. PBMCs were isolated and then treated as follows: control groups (untreated, treated with BSA 1% for 12 h), CA groups (treated with 50 μM CA for 6 h), palmitate groups (treated with 500 μM palmitate for 12 h), palmitate + CA groups (treated with 500 μM palmitate for 12 h and then treated with 50 μM CA for 6 h). Finally, sphingosine kinase 1 (SPHK1) and sphingosine 1-phosphate receptor 1 (S1PR1) genes expression were evaluated by real-time PCR and S1PR1 protein levels were quantified using ELISA.

Results

Palmitate significantly increased SPHK1 and S1PR1 genes expression and S1PR1 protein levels in PBMCs of patients with diabetes. However, CA ameliorates palmitate-increased SPHK1 and S1PR1 genes expression and S1PR1 levels in these cells.

Conclusion

These data indicate that CA could be considered as a novel S1P signaling pathway inhibitor through down regulation of SPHK1 and S1PR1.

Prognosis-related metabolic genes in the development of colorectal cancer progress and perspective

Colorectal cancer (CRC) is one of the most commonplace malignant tumors in the world. The occurrence and development of CRC are involved in numerous events. Metabolic reprogramming is one of the hallmarks of cancer and is convoluted and associated with carcinogenesis. Lots of metabolic genes are involved in the occurrence and progression of CRC. Study methods combining tumor genomics and metabolomics are more likely to explore this field in depth. In this mini-review, we make the latest progress and future prospects into the different molecular mechanisms of seven prognosis-related metabolic genes, we screened out in previous research, involved in the occurrence and development of CRC.

STAT proteins in cancer: orchestration of metabolism

Reprogrammed metabolism is a hallmark of cancer. However, the metabolic dependency of cancer, from tumour initiation through disease progression and therapy resistance, requires a spectrum of distinct reprogrammed cellular metabolic pathways. These pathways include aerobic glycolysis, oxidative phosphorylation, reactive oxygen species generation, de novo lipid synthesis, fatty acid β-oxidation, amino acid (notably glutamine) metabolism and mitochondrial metabolism. This Review highlights the central roles of signal transducer and activator of transcription (STAT) proteins, notably STAT3, STAT5, STAT6 and STAT1, in orchestrating the highly dynamic metabolism not only of cancer cells but also of immune cells and adipocytes in the tumour microenvironment. STAT proteins are able to shape distinct metabolic processes that regulate tumour progression and therapy resistance by transducing signals from metabolites, cytokines, growth factors and their receptors; defining genetic programmes that regulate a wide range of molecules involved in orchestration of metabolism in cancer and immune cells; and regulating mitochondrial activity at multiple levels, including energy metabolism and lipid-mediated mitochondrial integrity. Given the central role of STAT proteins in regulation of metabolic states, they are potential therapeutic targets for altering metabolic reprogramming in cancer.

HOXC11 drives lung adenocarcinoma progression through transcriptional regulation of SPHK1

Lung adenocarcinoma (LUAD) is a fatal threat to human health, while the mechanism remains unclear, and the therapy brings limited therapeutic effects. Transcription factor Homeobox C11 (HOXC11) was previously proved to be related to hind limbs and metanephric development during the embryonic phase, and its role in tumors has been gradually recognized. Our study found that HOXC11 overexpressed in LUAD and was associated with worse overall survival. Moreover, its expression in lung cancer was regulated by IκB kinase α (IKKα), a pivotal kinase in NF-κB signaling, which was related to the ubiquitination of HOXC11. We further proved that HOXC11 could enhance the ability of proliferation, migration, invasion, colony formation, and the progression of the cell cycle in LUAD cells. Meanwhile, it also accelerated the formation of subcutaneous and lung metastases tumors. In contrast, loss of HOXC11 in LUAD cells significantly inhibited these malignant phenotypes. At the same time, HOXC11 regulated the expression of sphingosine kinase 1 (SPHK1) by directly binding to its promoter region. Therefore, we conclude that HOXC11 impacts the development of LUAD and facilitates lung cancer progression by promoting the expression of SPHK1.

Sphingosine Kinase 2 in Stromal Fibroblasts Creates a Hospitable Tumor Microenvironment in Breast Cancer

Reciprocal interactions between breast cancer cells and the tumor microenvironment (TME) are important for cancer progression and metastasis. We report here that the deletion or inhibition of sphingosine kinase 2 (SphK2), which produces sphingosine-1-phosphate (S1P), markedly suppresses syngeneic breast tumor growth and lung metastasis in mice by creating a hostile microenvironment for tumor growth and invasion. SphK2 deficiency decreased S1P and concomitantly increased ceramides, including C16-ceramide, in stromal fibroblasts. Ceramide accumulation suppressed activation of cancer-associated fibroblasts (CAF) by upregulating stromal p53, which restrained production of tumor-promoting factors to reprogram the TME and to restrict breast cancer establishment. Ablation of p53 in SphK2-deficient fibroblasts reversed these effects, enabled CAF activation and promoted tumor growth and invasion. These data uncovered a novel role of SphK2 in regulating non-cell-autonomous functions of p53 in stromal fibroblasts and their transition to tumor-promoting CAFs, paving the way for the development of a strategy to target the TME and to enhance therapeutic efficacy.

SIGNIFICANCE

Sphingosine kinase 2 (SphK2) facilitates the activation of stromal fibroblasts to tumor-promoting cancer-associated fibroblasts by suppressing host p53 activity, revealing SphK2 as a potential target to reprogram the TME.

Phase I study of opaganib, an oral sphingosine kinase 2-specific inhibitor, in relapsed and/or refractory multiple myeloma

Multiple myeloma (MM) remains an incurable disease and there is an unmet medical need for novel therapeutic drugs that do not share similar mechanisms of action with currently available agents. Sphingosine kinase 2 (SK2) is an innovative molecular target for anticancer therapy. We previously reported that treatment with SK2 inhibitor opaganib inhibited myeloma tumor growth in vitro and in vivo in a mouse xenograft model. In the current study, we performed a phase I study of opaganib in patients with relapsed/refractory multiple myeloma (RRMM). Thirteen patients with RRMM previously treated with immunomodulatory agents and proteasome inhibitors were enrolled and treated with single-agent opaganib at three oral dosing regimens (250 mg BID, 500 mg BID, or 750 mg BID, 28 days as a cycle). Safety and maximal tolerated dose (MTD) were determined. Pharmacokinetics, pharmacodynamics, and correlative studies were also performed. Opaganib was well tolerated up to a dose of 750 mg BID. The most common possibly related adverse event (AE) was decreased neutrophil counts. There were no serious AEs considered to be related to opaganib. MTD was determined as at least 750 mg BID. On an intent-to-treat basis, one patient (7.7%) in the 500 mg BID dose cohort showed a very good partial response, and one other patient (7.7%) achieved stable disease for 3 months. SK2 is an innovative molecular target for antimyeloma therapy. The first-in-class SK2 inhibitor opaganib is generally safe for administration to RRMM patients, and has potential therapeutic activity in these patients. Clinicaltrials.gov: NCT02757326.

S1PR1/S1PR3-YAP signaling and S1P-ALOX15 signaling contribute to an aggressive behavior in obesity-lymphoma

BACKGROUND

Excess body weight has been found to associate with an increased risk of lymphomas and some metabolic pathways are currently recognized in lymphomagenesis. Bioactive lipid metabolites such as sphingosine-1-phosphate (S1P) have been proposed to play an important role linking obesity and lymphomas. However, the underlying mechanism(s) of S1P signaling in obesity-lymphomagenesis have not been well addressed.

METHODS

The gene expression of sphingosine kinase (SPHK), lymphoma prognosis, and S1P production were analyzed using Gene Expression Omnibus (GEO) and human lymphoma tissue array. Obesity-lymphoma mouse models and lymphoma cell lines were used to investigate the S1P/SPHK-YAP axis contributing to obesity-lymphomagenesis. By using the mouse models and a monocyte cell line, S1P-mediated polarization of macrophages in the tumor microenvironment were investigated.

RESULTS

In human study, up-regulated S1P/SPHK1 was found in human lymphomas, while obesity negatively impacted progression-free survival and overall survival in lymphoma patients. In animal study, obesity-lymphoma mice showed an aggressive tumor growth pattern. Both in vivo and in vitro data suggested the existence of S1P-YAP axis in lymphoma cells, while the S1P-ALOX15 signaling mediated macrophage polarization towards TAMs exacerbated the lymphomagenesis. In addition, treatment with resveratrol in obesity-lymphoma mice showed profound effects of anti-lymphomagenesis, via down-regulating S1P-YAP axis and modulating polarization of macrophages.

CONCLUSION

S1P/S1PR initiated the feedback loops, whereby S1P-S1PR1/S1PR3-YAP signaling mediated lymphomagenesis contributing to tumor aggressive growth, while S1P-ALOX15 signaling mediated TAMs contributing to immunosuppressive microenvironment in obesity-lymphoma. S1P-targeted therapy could be potentially effective and immune-enhancive against obesity-lymphomagenesis.

The Adipocyte-Macrophage Relationship in Cancer: A Potential Target for Antioxidant Therapy

Obesity has emerged as a major public health concern with a staggering 39% worldwide prevalence as of 2021. Given the magnitude of the problem and considering its association with chronic low-grade systemic inflammation, it does not come as a surprise that obesity is now considered one of the major risk factors for the development of several chronic diseases, such as diabetes, cardiovascular problems, and cancer. Adipose tissue dysfunction in obesity has taken center stage in understanding how changes in its components, particularly adipocytes and macrophages, participate in such processes. In this review, we will initially focus on how changes in adipose tissue upon excess fat accumulation generate endocrine signals that promote cancer development. Moreover, the tumor microenvironment or stroma, which is also critical in cancer development, contains macrophages and adipocytes, which, in reciprocal paracrine communication with cancer cells, generate relevant signals. We will discuss how paracrine signaling in the tumor microenvironment between cancer cells, macrophages, and adipocytes favors cancer development and progression. Finally, as reactive oxygen species participate in many of these signaling pathways, we will summarize the information available on how antioxidants can limit the effects of endocrine and paracrine signaling due to dysfunctional adipose tissue components in obesity.

Targeting SPHK1/S1PR3-regulated S-1-P metabolic disorder triggers autophagic cell death in pulmonary lymphangiomyomatosis (LAM)

Lymphangioleiomyomatosis (LAM), a progressive pulmonary disease exclusively affecting females, is caused by defects or mutations in the coding gene tuberous sclerosis complex 1 (TSC1) or TSC2, causing the mammalian target of rapamycin complex 1 (mTORC1) activation and autophagy inhibition. Clinically, rapamycin shows limited cytocidal effects, and LAM recurs after drug withdrawal. In this study, we demonstrated that TSC2 negatively regulated the sphingolipid metabolism pathway and the expressions of sphingosine kinase 1 (SPHK1) and sphingosine-1-phosphate receptor 3 (S1PR3) were significantly elevated in LAM patient-derived TSC2-deficient cells compared to TSC2-addback cells, insensitive to rapamycin treatment and estrogen stimulation. Knockdown of SPHK1 showed reduced viability, migration and invasion in TSC2-deficient cells. Selective SPHK1 antagonist PF543 potently suppressed the viability of TSC2-deficient cells and induced autophagy-mediated cell death. Meanwhile, the cognate receptor S1PR3 was identified to mediating the tumorigenic effects of sphingosine-1-phosphate (S1P). Treatment with TY52156, a selective antagonist for S1PR3, or genetic silencing using S1PR3-siRNA suppressed the viability of TSC2-deficient cells. Both SPHK1 and S1PR3 inhibitors markedly exhibited antitumor effect in a xenograft model of TSC2-null cells, restored autophagy level, and triggered cell death. Together, we identified novel rapamycin-insensitive sphingosine metabolic signatures in TSC2-null LAM cells. Therapeutic targeting of aberrant SPHK1/S1P/S1PR3 signaling may have potent therapeutic benefit for patients with TSC/LAM or other hyperactive mTOR neoplasms with autophagy inhibition.

Obesity Programs Macrophages to Support Cancer Progression

Obesity induces multifactorial effects such as dyslipidemia, insulin resistance, and arterial hypertension that influence the progression of many diseases. Obesity is associated with an increased incidence of cancers, and multiple mechanisms link obesity with cancer initiation and progression. Macrophages participate in the homeostasis of adipose tissue and play an important role in cancer. Adipose tissue expansion in obesity alters the balance between pro- and anti-inflammatory macrophages, which is a primary cause of inflammation. Chronic low-grade inflammation driven by macrophages is also an important characteristic of cancer. Adipocytes secrete various adipokines, including adiponectin, leptin, IL6, and TNFα, that influence macrophage behavior and tumor progression. Furthermore, other metabolic effects of obesity, such as hyperlipidemia, hyperglycemia, and hypercholesterolemia, can also regulate macrophage functionality in cancer. This review summarizes how obesity influences macrophage-tumor cell interactions and the role of macrophages in the response to anticancer therapies under obese conditions.

Highly active selenium nanotherapeutics combined with metformin to achieve synergistic sensitizing effect on NK cells for osteosarcoma therapy

NK cells-based cancer therapy combined with chemotherapeutic drugs for the treatment of tumors can enhance the immunosensitivity of NK cells, increase the expression of NK cell receptors, and eventually boost the killing effect of NK cells on cancer cells. Selenium (Se) with different chemical structures can be metabolized into selenoproteins to regulate tumor and immune cells' fate and functions. Herein, we found that, functionalized Se nanoparticles (SeNPs) combining with metformin (met) could amply the immunotherapeutic effects of NK92 cells against osteosarcoma cancer. The results revealed that TW80-SeNPs combined with met had the optimum performance on NK92 cells for HepG2 cells, owing to the increased ROS in HepG2 cells and the augmented expression of cell surface receptor proteins ULBP-3/4, PD-L1, MICA, and NK92 cell surface receptor proteins PD-1 and FasL. Additionally, TW80-SeNPs were gradually metabolized into selenoproteins (Gpx4 and TR1) into human osteosarcoma MG63 cells to reinforce the anticancer effect of NK92 cells by regulating the redox balance in the tumor microenvironment. This study provides a therapeutic approach in treating cancer itself or diabetes coupled with cancer. Moreover, it provides a multidrug strategy to improve immune cell function in practical applications, especially for synergistic immunotherapy of osteosarcoma.