Sphingosine-1-phosphate links persistent STAT3 activation, chronic intestinal inflammation, and development of colitis-associated cancer

Integrating 16 S rRNA gene sequencing and metabolomics analysis to reveal the mechanism of Angelica sinensis oil in alleviating ulcerative colitis in mice

Angelica sinensis (Oliv.) Diels (AS) is a commonly used herbal medicine and culinary spice known for its gastrointestinal protective properties. Angelica sinensis oil (AO) is the main bioactive component of AS. However, the therapeutic effects and mechanisms of AO on the gastrointestinal tract remain unclear. In this study, we aim to investigated the potential of AO in restoring gut microbiota disorder and metabolic disruptions associated with ulcerative colitis (UC). A systematic chemical characterization of AO was conducted using GC×GC-Q TOF-MS. A UC mouse model was established by freely drinking DSS to assess the efficacy of AO. Utilizing 16 S rRNA sequencing in combination with untargeted metabolomics analysis of serum, we identified alterations in gut microbiota, differential metabolites, and pathways influenced by AO in UC treatment, thereby elucidating the therapeutic mechanism of AO in UC management. Pharmacodynamic results indicated that AO effectively inhibited the content of inflammation mediators, such as Interleukin-1β, Interleukin-6 and tumor necrosis factor-α, and proserved colon tissue integrity in UC mice. Furthermore, AO significantly downregulated the abundance of pathogenic bacteria (Bacteroidetes, Proteobacteria, and Desulfobacteriaceae) while increasing the abundance of beneficial bacteria (Firmicutes, Blautia, Akkermansia, and Lachnospiraceae). Metabolomics analysis highlighted significant disruptions in endogenous metabolism in UC mice, with a notable restoration of SphK1 and S1P levels following AO administration. Besides, we discovered that AO regulated the balance of sphingolipid metabolism and protected the intestinal barrier, potentially through the SphK1/MAPK signaling pathway. Overall, this study indicated that AO effectively ameliorates the clinical manifestations of UC by synergistically regulating gut microbe and metabolite homeostasis. AO emerges as a potential functional and therapeutic ingredient for UC treatment.

Sphingosine-1-phosphate signaling regulates the ability of Müller glia to become neurogenic, proliferating progenitor-like cells

The purpose of these studies is to investigate how Sphingosine-1-phosphate (S1P) signaling regulates glial phenotype, dedifferentiation of Müller glia (MG), reprogramming into proliferating MG-derived progenitor cells (MGPCs), and neuronal differentiation of the progeny of MGPCs. We found that S1P-related genes are highly expressed by retinal neurons and glia, and levels of expression were dynamically regulated following retinal damage. S1PR1 is highly expressed by resting MG and is rapidly downregulated following acute retinal damage. Drug treatments that activate S1PR1 or increase levels of S1P suppressed the formation of MGPCs, whereas treatments that inhibit S1PR1 or decreased levels of S1P stimulated the formation of MGPCs. Inhibition of S1PR1 or SPHK1 significantly enhanced the neuronal differentiation of the progeny of MGPCs. Further, ablation of microglia from the retina, wherein the formation of MGPCs in damaged retinas is impaired, has a significant impact upon expression patterns of S1P-related genes in MG. Inhibition of S1PR1 and SPHK1 partially rescued the formation of MGPCs in damaged retinas missing microglia. Finally, we show that TGFβ/Smad3 signaling in the resting retina maintains S1PR1 expression in MG. We conclude that the S1P signaling is dynamically regulated in MG and MGPCs and activation of S1P signaling depends, in part, on signals produced by reactive microglia.

Targeting the Sphingosine-1-Phosphate Pathway: New Opportunities in Inflammatory Bowel Disease Management

Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC) are chronic immune-mediated diseases which primarily target the intestines. In recent years, the development and regulatory approval of various immunotherapies, both biological agents and small molecules, that target specific pathways of the IBD-associated inflammatory cascade have revolutionized the treatment of IBD. Small molecules offer the advantages of oral administration and short wash-out times. Sphingosine-1-phosphate (S1P) is a bioactive metabolite of ceramide, which exerts its functions after binding to five G-protein-coupled receptors (S1PR1-S1PR5). Concerning IBD, S1P participates in the egress of lymphocytes from the secondary lymphoid tissue and their re-circulation to sites of inflammation, mainly through S1PR1 binding. In addition, this system facilitates the differentiation of T-helper cells towards proinflammatory immunophenotypes. Recently, S1P modulators have offered a valuable addition to the IBD treatment armamentarium. They exert their anti-inflammatory function via sequestration of T cell subsets in the lymphoid tissues and prevention of gut homing. In this review, we revisit the role of the S1P/S1PR axis in the pathogenesis of IBD and discuss efficacy and safety data from clinical trials and real-world reports on the two S1PR modulators, ozanimod and etrasimod, that are currently approved for IBD treatment, and comment on their potential positioning in the IBD day-to-day management. We also present recent data on emerging S1P modulators. Finally, based on the successes and failures of S1PR modulators in IBD, we discuss future avenues of IBD treatments targeting the S1P/S1PR axis.

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.

Repurposing metformin as adjuvant therapy in patients with ulcerative colitis treated with mesalamine: A randomized controlled double-blinded study

BACKGROUND

Ulcerative colitis (UC) is a type of inflammatory bowel disease associated with persistent inflammation. Animal studies proved the efficacy of metformin in UC.

AIM

To investigate the potential role of metformin and its protective pathways in patients with UC.

METHODS

This is a randomized, controlled, and double-blinded clinical trial that included 60 participants with mild to moderate UC and was divided randomly into two groups (n = 30). For 6 months, the mesalamine group received 1 g of mesalamine three times daily (t.i.d.). For six months, the metformin group received mesalamine 1 g t.i.d. and metformin 500 mg twice daily. A gastroenterologist evaluated patients at baseline and 6 months after starting the treatment in order to measure serum levels of zonulin, sphingosine 1 phosphate (S1P), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). Biopsies from the colon were used to measure gene expression of zonula occuldin-1 (ZO-1), signal transducer and activator of factor-3 (STAT-3), and intracellular adhesion molecule-1 (ICAM-1). The numeric pain rating scale (NRS) and partial Mayo score were also assessed for each patient.

RESULTS

When compared to the mesalamine group, the metformin group demonstrated a statistical decrease in serum IL-6, zonulin, TNF-α, SIP, gene expression of ICAM-1 and STAT-3, and a significant increase in colonic ZO-1 when compared to the mesalamine group. The metformin group also showed a significant decrease in NRS and partial Mayo score index in comparison with the mesalamine group.

CONCLUSION

Metformin may be a promising additional therapy for UC patients. Trial registration identifier: NCT05553704.

An inducible sphingosine kinase 1 in hepatic stellate cells potentiates liver fibrosis

Hepatic stellate cells (HSCs) play a role in hepatic fibrosis and sphingosine kinase (SphK) is involved in biological processes. As studies on the regulatory mechanisms and functions of SphK in HSCs during liver fibrosis are currently limited, this study aimed to elucidate the regulatory mechanism and connected pathways of SphK upon HSC activation. The expression of SphK1 was higher in HSCs than in hepatocytes, and upregulated in activated primary HSCs. SphK1 was also increased in liver homogenates of carbon tetrachloride-treated or bile duct ligated mice and in transforming growth factor-β (TGF-β)-treated LX-2 cells. TGF-β-mediated SphK1 induction was due to Smad3 signaling in LX-2 cells. SphK1 modulation altered the expression of liver fibrogenesis-related genes. This SphK1-mediated profibrogenic effect was dependent on SphK1/sphingosine-1-phosphate/sphingosine-1-phosphate receptor signaling through ERK. Epigallocatechin gallate blocked TGF-β-induced SphK1 expression and hepatic fibrogenesis by attenuating Smad and MAPK activation. SphK1 induced by TGF-β facilitates HSC activation and liver fibrogenesis, which is reversed by epigallocatechin gallate. Accordingly, SphK1 and related signal transduction may be utilized to treat liver fibrosis.

Nanoparticle co-delivery of carboplatin and PF543 restores platinum sensitivity in ovarian cancer models through inhibiting platinum-induced pro-survival pathway activation

Resistance to platinum-based chemotherapy is the major cause of poor prognosis and cancer-associated mortality in ovarian cancer patients, so novel therapeutic strategies to restore platinum sensitivity are needed to improve patient outcomes. Sphingosine Kinase (SphK) 1 is involved in regulating multiple pro-survival pathways, key mediators in the sensitivity of tumor cells toward platinum. By encapsulating CBP and the SphK1 inhibitor PF543 in PLGA (poly lactic-co-glycolic acid) nanoparticles, a dual-drug delivery system (C/PNPs) was formed to simultaneously deliver CBP and PF543. The physicochemical characteristics, cell uptake rate and biodistribution behavior of C/PNPs were evaluated. Then the anti-tumor ability of C/PNPs in vitro and in vivo was further investigated. The C/PNPs could deliver CBP and PF543 simultaneously to a platinum-insensitive cell line (SKOV3) both in vitro and in vivo. Furthermore, benefiting from the enhanced permeability and retention (EPR) effect of PLGA NPs, C/PNPs exhibited an improved tumor region accumulation. As a result, a synergistic anti-tumor effect was found in the SKOV3 tumor-bearing mice, with tumor volume inhibiting rates of 84.64% and no side effects in major organs. The mechanistic studies confirmed that the inhibition of SphK1 by PF543 sensitized SKOV3 cells to CBP chemotherapy, partly by inhibiting the CBP-induced activation of pro-survival pathways, including ERK, AKT and STAT3 signaling. Our study reveals that C/PNPs can serve as an efficient dual-drug delivery system to restore platinum sensitivity in ovarian cancer models partly through inhibiting platinum-induced pro-survival pathway activation.

The diverse roles of sphingolipids in inflammatory bowel disease

The incidence of inflammatory bowel disease (IBD) has increased over the last 20 years. A variety of causes, both physiological and environmental, contribute to the initiation and progression of IBD, making disease management challenging. Current treatment options target various aspects of the immune response to dampen intestinal inflammation; however, their effectiveness at retaining remission, their side effects, and loss of response from patients over time warrant further investigation. Finding a common thread within the multitude causes of IBD is critical in developing robust treatment options. Sphingolipids are evolutionary conserved bioactive lipids universally generated in all cell types. This diverse lipid family is involved in a variety of fundamental, yet sometimes opposing, processes such as proliferation and apoptosis. Implicated as regulators in intestinal diseases, sphingolipids are a potential cornerstone in understanding IBD. Herein we will describe the role of host- and microbial-derived sphingolipids as they relate to the many factors of intestinal health and IBD.

Targeting apoptosis in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most prevalent subtype of renal cancer, accounting for approximately 80% of all renal cell cancers. Due to its exceptional inter- and intratumor heterogeneity, it is highly resistant to conventional systemic therapies. Targeting the evasion of cell death, one of cancer's hallmarks, is currently emerging as an alternative strategy for ccRCC. In this article, we review the current state of apoptosis-inducing therapies against ccRCC, including antisense oligonucleotides, BH3 mimetics, histone deacetylase inhibitors, cyclin-kinase inhibitors, inhibitors of apoptosis protein antagonists, and monoclonal antibodies. Although preclinical studies have shown encouraging results, these compounds fail to improve patients' outcomes significantly. Current evidence suggests that inducing apoptosis in ccRCC may promote tumor progression through apoptosis-induced proliferation, anastasis, and apoptosis-induced nuclear expulsion. Therefore, re-evaluating this approach is expected to enable successful preclinical-to-clinical translation.

Sphingolipid Signaling and Complement Activation in Glioblastoma: A Promising Avenue for Therapeutic Intervention

Glioblastoma is the most common and aggressive type of malignant brain tumor with a poor prognosis due to the lack of effective treatment options. Therefore, new treatment options are required. Sphingolipids are essential components of the cell membrane, while complement components are integral to innate immunity, and both play a critical role in regulating glioblastoma survival signaling. This review focuses on recent studies investigating the functional roles of sphingolipid metabolism and complement activation signaling in glioblastoma. It also discusses how targeting these two systems together may emerge as a novel therapeutic approach.

Advances in molecular mechanisms of inflammatory bowel disease‑associated colorectal cancer (Review)

The link between inflammation and cancer is well documented and colonic inflammation caused by inflammatory bowel disease (IBD) is thought to be a high-risk factor for the development of colorectal cancer (CRC). The complex crosstalk between epithelial and inflammatory cells is thought to underlie the progression from inflammation to cancer. The present review collates and summarises recent advances in the understanding of the pathogenesis of IBD-associated CRC (IBD-CRC), including the oncogenic mechanisms of the main inflammatory signalling pathways and genetic alterations induced by oxidative stress during colonic inflammation, and discusses the crosstalk between the tumour microenvironment, intestinal flora and host immune factors during inflammatory oncogenesis in colitis-associated CRC. In addition, the therapeutic implications of anti-inflammatory therapy for IBD-CRC were discussed, intending to provide new insight into improve clinical practice.

The histamine H4 receptor antagonist 1-[(5-chloro-2,3-dihydro-1-benzofuran-2-yl)methyl]-4-methyl-piperazine(LINS01007) prevents the development of DSS-induced colitis in mice

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with growing incidence worldwide. Our group reported the compound 5-choro-1-[(2,3-dihydro-1-benzofuran-2-yl)methyl]piperazine (LINS01007) as H4R antagonist (pKi 6.2) and therefore the effects and pharmacological efficacy on a DSS-induced mice model of UC were assessed in this work. Experimental acute colitis was induced in male BALB/c mice (n = 5-10) by administering 3 % DSS in the drinking water for six days. The test compound LINS01007 was administered daily i.p. (5 mg/kg) and compared to control group without treatment. Body weight, water and food consumption, and the presence of fecal blood were monitored during 7-day treatment period. The levels of inflammatory markers (PGE2, COX-2, IL-6, NF-κB and STAT3) were also analyzed. Animals subjected to the acute colitis protocol showed a reduction in water and food intake from the fourth day (p < 0.05) and these events were prevented by LINS01007. Histological signs of edema, hyperplasia and disorganized intestinal crypts, as well as neutrophilic infiltrations, were found in control mice while these findings were significantly reduced in animals treated with LINS01007. Significant reductions in the levels of PGE2, COX-2, IL-6, NF-κB and STAT3 were observed in the serum and tissue of treated animals. The results demonstrated the significant effects of LINS01007 against DSS-induced colitis, highlighting the potential of H4R antagonism as promising treatment for this condition.

Prognostic potential of lipid profiling in cancer patients: a systematic review of mass spectrometry-based studies

Cancer prognosis remains a critical clinical challenge. Lipidomic analysis via mass spectrometry (MS) offers the potential for objective prognostic prediction, leveraging the distinct lipid profiles of cancer patient-derived specimens. This review aims to systematically summarize the application of MS-based lipidomic analysis in prognostic prediction for cancer patients. Our systematic review summarized 38 studies from the past decade that attempted prognostic prediction of cancer patients through lipidomics. Commonly analyzed cancers included colorectal, prostate, and breast cancers. Liquid (serum and urine) and tissue samples were equally used, with liquid chromatography-tandem MS being the most common analytical platform. The most frequently evaluated prognostic outcomes were overall survival, stage, and recurrence. Thirty-eight lipid markers (including phosphatidylcholine, ceramide, triglyceride, lysophosphatidylcholine, sphingomyelin, phosphatidylethanolamine, diacylglycerol, phosphatidic acid, phosphatidylserine, lysophosphatidylethanolamine, lysophosphatidic acid, dihydroceramide, prostaglandin, sphingosine-1-phosphate, phosphatidylinosito, fatty acid, glucosylceramide and lactosylceramide) were identified as prognostic factors, demonstrating potential for clinical application. In conclusion, the potential for developing lipidomics in cancer prognostic prediction was demonstrated. However, the field is still nascent, necessitating future studies for validating and establishing lipid markers as reliable prognostic tools in clinical practice.

Signaling controversy and future therapeutical perspectives of targeting sphingolipid network in cancer immune editing and resistance to tumor necrosis factor-α immunotherapy

Anticancer immune surveillance and immunotherapies trigger activation of cytotoxic cytokine signaling, including tumor necrosis factor-α (TNF-α) and TNF-related apoptosis-inducing ligand (TRAIL) pathways. The pro-inflammatory cytokine TNF-α may be secreted by stromal cells, tumor-associated macrophages, and by cancer cells, indicating a prominent role in the tumor microenvironment (TME). However, tumors manage to adapt, escape immune surveillance, and ultimately develop resistance to the cytotoxic effects of TNF-α. The mechanisms by which cancer cells evade host immunity is a central topic of current cancer research. Resistance to TNF-α is mediated by diverse molecular mechanisms, such as mutation or downregulation of TNF/TRAIL receptors, as well as activation of anti-apoptotic enzymes and transcription factors. TNF-α signaling is also mediated by sphingosine kinases (SphK1 and SphK2), which are responsible for synthesis of the growth-stimulating phospholipid, sphingosine-1-phosphate (S1P). Multiple studies have demonstrated the crucial role of S1P and its transmembrane receptors (S1PR) in both the regulation of inflammatory responses and progression of cancer. Considering that the SphK/S1P/S1PR axis mediates cancer resistance, this sphingolipid signaling pathway is of mechanistic significance when considering immunotherapy-resistant malignancies. However, the exact mechanism by which sphingolipids contribute to the evasion of immune surveillance and abrogation of TNF-α-induced apoptosis remains largely unclear. This study reviews mechanisms of TNF-α-resistance in cancer cells, with emphasis on the pro-survival and immunomodulatory effects of sphingolipids. Inhibition of SphK/S1P-linked pro-survival branch may facilitate reactivation of the pro-apoptotic TNF superfamily effects, although the role of SphK/S1P inhibitors in the regulation of the TME and lymphocyte trafficking should be thoroughly assessed in future studies.

M2 tumor-associated macrophages and CXCL2 induce lipid remodeling in hepatocellular carcinoma cell lines

Primary hepatocellular carcinoma (HCC) is one of the most common malignant tumors, but its pathogenesis remains incompletely elucidated. Recently, many studies indicated that lipid remodeling plays an important role in the occurrence and development of HCC. Furthermore, lipids have been proven to be indispensable mediators in promoting communication between tumor cells and extracellular matrix in the tumor microenvironment. Thus, this study aims to comprehensively investigate the process of lipid remodeling during HCC metastasis based on the LC-electrospray ionization-MS (LC-ESI-MS) combined with multiple reaction monitoring technology. M2 tumor-associated macrophages and the recombinant human protein CXCL2 were used to simulate the tumor microenvironment. After co-incubating SMMC7721 and MHCC97-H cell lines with M2 tumor-associated macrophages or the recombinant human protein CXCL2 for 48 h, LC-ESI-MS was used to quantify the levels of two major classes of lipid molecules, namely, glycerophospholipids and sphingolipids. Our results suggest that lipid remodeling in the tumor microenvironment may promote the migration and invasion of HCC cell lines.

Histological differentiation between sporadic and colitis-associated intestinal cancer in a nationwide study: A propensity-score-matched analysis

BACKGROUND AND AIM

Colitis-associated intestinal cancer (CAC) can develop in patients with inflammatory bowel disease; however, the malignant grade of CAC may differ from that of sporadic colorectal cancer (CRC). Therefore, we compared histological findings distinct from cancer stage between CAC and sporadic CRC to evaluate the features of CAC.

METHODS

We reviewed the clinical and histological data collected from a nationwide database in Japan between 1983 and 2020. Patient characteristics were compared to distinguish ulcerative colitis (UC), Crohn's disease (CD), and sporadic CRC. Comparisons were performed by using all collected data and propensity score-matched data.

RESULTS

A total of 1077 patients with UC-CAC, 297 with CD-CAC, and 136 927 with sporadic CRC were included. Although the prevalence of well or moderately differentiated adenocarcinoma (Tub1 and Tub2) decreased according to tumor progression for all diseases (P < 0.01), the prevalence of other histological findings, including signet ring cell carcinoma, mucinous carcinoma, poorly differentiated adenocarcinoma, or squamous cell carcinoma, was significantly higher in CAC than in sporadic CRC. Based on propensity score-matched data for 982 patients with UC and 268 with CD, the prevalence of histological findings other than Tub1 and Tub2 was also significantly higher in those with CAC. At pT4, mucinous carcinoma occurred at a significantly higher rate in patients with CD (45/86 [52.3%]) than in those with sporadic CRC (13/88 [14.8%]) (P < 0.01).

CONCLUSION

CAC, including early-stage CAC, has a higher malignant grade than sporadic CRC, and this difference increases in significance with tumor progression.

A critical review of advances in tumor metabolism abnormalities induced by nitrosamine disinfection by-products in drinking water

Intensified sanitation practices amid the recent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak might result in the increased release of chloramine disinfectants into surface water, significantly promoting the formation of nitrosamine disinfection by-products (DBPs) in drinking water. Unfortunately, these nitrosamine DBPs exhibit significant genotoxic, carcinogenic, and mutagenic properties, whereas chlorinating disinfectants remain in global practice. The current review provides valuable insights into the occurrence, identification, contamination status, exposure limits, and toxicity of the new unregulated disinfection by-products (nitrosamine DBPs) in drinking water. As a result, concentrations of nitrosamine DBPs far exceed allowable limits in drinking water, and prolonged exposure has the potential to cause metabolic disorders, a critical step in tumor initiation and progression. Importantly, based on recent research, we have concluded the role of nitrosamines DBPs in different metabolic pathways. Remarkably, nitrosamine DBPs can induce chronic inflammation and initiate tumors by activating sphingolipid and polyunsaturated fatty acid metabolism. Regarding amino acid and nucleotide metabolism, nitrosamine DBPs can inhibit tryptophan metabolism and de novo nucleotide synthesis. Moreover, inhibition of de novo nucleotide synthesis fails to repair DNA damage induced by nitrosamines. Additionally, the accumulation of lactate induced by nitrosamine DBPs may act as a pivotal signaling molecule in communication within the tumor microenvironment. However, with the advancement of tumor metabolomics, understanding the role of nitrosamine DBPs in causing cancer by inducing metabolic abnormalities significantly lags behind, and specific mechanisms of toxic effects are not clearly defined. Urgently, further studies exploring this promising area are needed.

Combination of bazedoxifene with chemotherapy and SMAC-mimetics for the treatment of colorectal cancer

Excessive STAT3 signalling via gp130, the shared receptor subunit for IL-6 and IL-11, contributes to disease progression and poor survival outcomes in patients with colorectal cancer. Here, we provide evidence that bazedoxifene inhibits tumour growth via direct interaction with the gp130 receptor to suppress IL-6 and IL-11-mediated STAT3 signalling. Additionally, bazedoxifene combined with chemotherapy synergistically reduced cell proliferation and induced apoptosis in patient-derived colon cancer organoids. We elucidated that the primary mechanism of anti-tumour activity conferred by bazedoxifene treatment occurs via pro-apoptotic responses in tumour cells. Co-treatment with bazedoxifene and the SMAC-mimetics, LCL161 or Birinapant, that target the IAP family of proteins, demonstrated increased apoptosis and reduced proliferation in colorectal cancer cells. Our findings provide evidence that bazedoxifene treatment could be combined with SMAC-mimetics and chemotherapy to enhance tumour cell apoptosis in colorectal cancer, where gp130 receptor signalling promotes tumour growth and progression.

How do sphingosine-1-phosphate affect immune cells to resolve inflammation?

Inflammation is an important immune response of the body. It is a physiological process of self-repair and defense against pathogens taken up by biological tissues when stimulated by damage factors such as trauma and infection. Inflammation is the main cause of high morbidity and mortality in most diseases and is the physiological basis of the disease. Targeted therapeutic strategies can achieve efficient toxicity clearance at the inflammatory site, reduce complications, and reduce mortality. Sphingosine-1-phosphate (S1P), a lipid signaling molecule, is involved in immune cell transport by binding to S1P receptors (S1PRs). It plays a key role in innate and adaptive immune responses and is closely related to inflammation. In homeostasis, lymphocytes follow an S1P concentration gradient from the tissues into circulation. One widely accepted mechanism is that during the inflammatory immune response, the S1P gradient is altered, and lymphocytes are blocked from entering the circulation and are, therefore, unable to reach the inflammatory site. However, the full mechanism of its involvement in inflammation is not fully understood. This review focuses on bacterial and viral infections, autoimmune diseases, and immunological aspects of the Sphks/S1P/S1PRs signaling pathway, highlighting their role in promoting intradial-adaptive immune interactions. How S1P signaling is regulated in inflammation and how S1P shapes immune responses through immune cells are explained in detail. We teased apart the immune cell composition of S1P signaling and the critical role of S1P pathway modulators in the host inflammatory immune system. By understanding the role of S1P in the pathogenesis of inflammatory diseases, we linked the genomic studies of S1P-targeted drugs in inflammatory diseases to provide a basis for targeted drug development.

Therapeutic Potential for Sphingolipids in Inflammatory Bowel Disease and Colorectal Cancer

Inflammatory bowel disease (IBD), characterized by chronic inflammation in the intestinal tract, increases the risk for the development of colorectal cancer (CRC). Sphingolipids, which have been implicated in IBD and CRC, are a class of bioactive lipids that regulate cell signaling, differentiation, apoptosis, inflammation, and survival. The balance between ceramide (Cer), the central sphingolipid involved in apoptosis and differentiation, and sphingosine-1-phosphate (S1P), a potent signaling molecule involved in proliferation and inflammation, is vital for the maintenance of normal cellular function. Altered sphingolipid metabolism has been implicated in IBD and CRC, with many studies highlighting the importance of S1P in inflammatory signaling and pro-survival pathways. A myriad of sphingolipid analogues, inhibitors, and modulators have been developed to target the sphingolipid metabolic pathway. In this review, the efficacy and therapeutic potential for modulation of sphingolipid metabolism in IBD and CRC will be discussed.

Integrated Metabolomics and Gut Microbiome Analysis Reveals the Efficacy of a Phytochemical Constituent in the Management of Ulcerative Colitis

SCOPE

Cinnamaldehyde (CAH), a phytochemical constituent isolated from cinnamon, is gaining attention due to its nutritional and medicinal benefits. This study aimed to investigate the potential role of CAH in the treatment of ulcerative colitis (UC).

METHODS AND RESULTS

Integrated metabolomics and gut microbiome analysis are performed for 2,4,6-trinitrobenzenesulfonic acid (TNBS) induced UC rats. The effect of CAH on colonic inflammation, lipid peroxidation, metabolic profiles, and gut microbiota is systematically explored. It finds that CAH improves the colitis-related symptoms, decreases disease activity index, increases the colon length and body weight, and alleviates histologic inflammation of UC rats. These therapeutic effects of CAH are due to suppression of inflammation and lipid peroxidation. Moreover, multi-omics analysis reveals that CAH treatment cause changes in plasma metabolome and gut microbiome in UC rats. CAH regulates lipid metabolic processes, especially phosphatidylcholines, lysophosphatidylcholines, and polyunsaturated fatty acids. Meanwhile, CAH modulates the gut microbial structure by restraining pathogenic bacteria (such as Helicobacter) and increasing probiotic bacteria (such as Bifidobacterium and Lactobacillus).

CONCLUSIONS

These results indicate that CAH exerts a beneficial role in UC by synergistic modulating the balance in gut microbiota and the associated metabolites, and highlights the nutritional and medicinal value of CAH in UC management.

Pancreatic Acinar Cells-Derived Sphingosine-1-Phosphate Contributes to Fibrosis of Chronic Pancreatitis via Inducing Autophagy and Activation of Pancreatic Stellate Cells

BACKGROUND & AIMS

Studies have demonstrated that activated pancreatic stellate cells (PSCs) play a crucial role in pancreatic fibrogenesis in chronic pancreatitis (CP); however, the precise mechanism for PSCs activation has not been fully elucidated. We analyzed the role of injured pancreatic acinar cells (iPACs) in the activation of PSCs of CP.

METHODS

Sphingosine kinase 1 (SPHK1)/sphingosine-1-phosphate (S1P) signaling was evaluated in experimental CP induced by cerulein injection or pancreatic duct ligation, as well as in PACs injured by cholecystokinin. The activation of PSCs and pancreatic fibrosis in CP samples was evaluated by immunohistochemical and immunofluorescence analyses. In vitro coculture assay of iPACs and PSCs was created to evaluate the effect of the SPHK1/S1P pathway and S1P receptor 2 (SIPR2) on autophagy and activation of PSCs. The pathogenesis of CP was assessed in SPHK1-/- mice or PACs-specific SPHK1-knockdown mice with recombinant adeno-associated virus serotypes 9-SPHK1-knockdown, as well as in mice treated with inhibitor of SPHK1 and S1P receptor 2 (S1PR2).

RESULTS

SPHK1/S1P was remarkably increased in iPACs and acinar cells in pancreatic tissues of CP mice. Meanwhile, the pathogenesis, fibrosis, and PSCs activation of CP was significantly prevented in SPHK1-/- mice and recombinant adeno-associated virus serotypes 9-SPHK1-knockdown mice. Meanwhile, iPACs obviously activated PSCs, which was prevented by SPHK1 knockdown in iPACs. Moreover, iPACs-derived S1P specifically combined to S1PR2 of PSCs, by which modulated 5' adenosine monophosphate-activated protein kinase/mechanistic target of rapamycin pathway and consequently induced autophagy and activation of PSCs. Furthermore, hypoxia-inducible factor 1-α and -2α promoted SPHK1 transcription of PACs under hypoxia conditions, which is a distinct characteristic of the CP microenvironment. Coincidently, inhibition of SPHK1 and S1PR2 activity with inhibitor PF-543 and JTE-013 obviously impeded pancreatic fibrogenesis of CP mice.

CONCLUSIONS

The activated SPHK1/S1P pathway in iPACs induces autophagy and activation of PSCs by regulating the S1PR2/5' adenosine monophosphate-activated protein kinase/mammalian target of rapamycin pathway, which promotes fibrogenesis of CP. The hypoxia microenvironment might contribute to the cross talk between PACs and PSCs in pathogenesis of CP.

Feline mammary carcinoma-derived extracellular vesicle promotes liver metastasis via sphingosine kinase-1-mediated premetastatic niche formation

BACKGROUND

Feline mammary carcinoma (FMC) is one of the most prevalent malignancies of female cats. FMC is highly metastatic and thus leads to poor disease outcomes. Among all metastases, liver metastasis occurs in about 25% of FMC patients. However, the mechanism underlying hepatic metastasis of FMC remains largely uncharacterized.

RESULTS

Herein, we demonstrate that FMC-derived extracellular vesicles (FMC-EVs) promotes the liver metastasis of FMC by activating hepatic stellate cells (HSCs) to prime a hepatic premetastatic niche (PMN). Moreover, we provide evidence that sphingosine kinase 1 (SK1) delivered by FMC-EV was pivotal for the activation of HSC and the formation of hepatic PMN. Depletion of SK1 impaired cargo sorting in FMC-EV and the EV-potentiated HSC activation, and abolished hepatic colonization of FMC cells.

CONCLUSIONS

Taken together, our findings uncover a previously uncharacterized mechanism underlying liver-metastasis of FMC and provide new insights into prognosis and treatment of this feline malignancy.

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.

Biphasic inflammatory response induced by intra-plantar injection of L-cysteine: Role of CBS-derived H2S and S1P/NO signaling

This study investigates the inflammatory response to intra-plantar injection of L-cysteine in a murine model. L-cysteine induces a two-phase response: an early phase lasting 6 h and a late phase peaking at 24 h and declining by 192 h. The early phase shows increased neutrophil accumulation at 2 h up to 24 h, followed by a reduction at 48 h. On the other hand, the late phase exhibits increased macrophage infiltration peaking at 96 h. Inhibition of cystathionine β-synthase (CBS), the first enzyme in the transsulfuration pathway, significantly reduces L-cysteine-induced edema, suggesting its dependence on CBS-derived hydrogen sulfide (H2S). Sequential formation of sphingosine-1-phosphate (S1P) preceding nitric oxide (NO) generation suggests the involvement of a CBS/S1P/NO axis in the inflammatory response. Inhibition of de novo sphingolipid biosynthesis, S1P1 receptor, and endothelial NO synthase (eNOS) attenuates L-cysteine-induced paw edema. These findings indicate a critical role of the CBS/H2S/S1P/NO signaling pathway in the development and maintenance of L-cysteine-induced inflammation. The co-presence of H2S and NO is necessary for inducing and sustaining the inflammatory response, as NaHS or L-arginine alone do not replicate the marked and prolonged inflammatory effect observed with L-cysteine. This study enhances our understanding of the complex molecular mechanisms of the interplay between NO and H2S pathways in inflammation and identifies potential therapeutic targets for inflammatory disorders.

FTY720 attenuates acute colitis via colonic T cells reduction and inhibition of M1 macrophages polarization independent of CCR2-mediated monocytes input

Ulcerative colitis (UC) is a complex multifactorial disease, of which the exact etiology is not fully understood. The inappropriate aggressive inflammatory response is closely related to the disease progression of UC. FTY720 is a sphingosine-1-phosphate receptor agonist and acts as a key immunomodulator in inflammation. This study aims to investigate the protective influence of FTY720 on inflammation in the DSS-induced colitis model. In the present study, the C57BL/6 mice and the CCR2-/- mice were exposed to 5% Dextran Sodium Sulfate (DSS) drinking water for 6 days followed by an injection of FTY720 (1 mg/kg/d) or vehicle (PBS) 6 times starting on the next day. The body weight, stool consistency, and occult blood were assessed daily. The inflammatory cytokines level in colon tissues and serum were assessed. Leukocyte subsets of bone marrow (BM), spleen, and colon were analyzed by flow cytometry. Our results demonstrated that FTY720 ameliorated the aberrant immune responses by trapping T cells and inhibiting the polarization of M1 macrophages in colitis mice. The effect of FTY720 on the increased number of colonic macrophages did not dependent on CCR2-mediated monocyte influx, despite most monocytes being reduced after DSS administration in the inflamed colon of CCR2-/- mice. Rather, depletion of CCR2 did not impact the protective influence of FTY720 on colonic injury in acute colitis. All these findings unravel a beneficial function of FTY720 in the inflammatory response to DSS-induced acute colitis, provided further insights into monocyte migration and might provide potential opportunities for UC therapeutic intervention.

A virally encoded GPCR drives glioblastoma through feed-forward activation of the SK1-S1P1 signaling axis

The G protein-coupled receptor (GPCR) US28 encoded by the human cytomegalovirus (HCMV) is associated with accelerated progression of glioblastomas, aggressive brain tumors with a generally poor prognosis. Here, we showed that US28 increased the malignancy of U251 glioblastoma cells by enhancing signaling mediated by sphingosine-1-phosphate (S1P), a bioactive lipid that stimulates oncogenic pathways in glioblastoma. US28 expression increased the abundance of the key components of the S1P signaling axis, including an enzyme that generates S1P [sphingosine kinase 1 (SK1)], an S1P receptor [S1P receptor 1 (S1P1)], and S1P itself. Enhanced S1P signaling promoted glioblastoma cell proliferation and survival by activating the kinases AKT and CHK1 and the transcriptional regulators cMYC and STAT3 and by increasing the abundance of cancerous inhibitor of PP2A (CIP2A), driving several feed-forward signaling loops. Inhibition of S1P signaling abrogated the proliferative and anti-apoptotic effects of US28. US28 also activated the S1P signaling axis in HCMV-infected cells. This study uncovers central roles for S1P and CIP2A in feed-forward signaling that contributes to the US28-mediated exacerbation of glioblastoma.

FTY720-P, a Biased S1PR Ligand, Increases Mitochondrial Function through STAT3 Activation in Cardiac Cells

FTY720 is an FDA-approved sphingosine derivative drug for the treatment of multiple sclerosis. This compound blocks lymphocyte egress from lymphoid organs and autoimmunity through sphingosine 1-phosphate (S1P) receptor blockage. Drug repurposing of FTY720 has revealed improvements in glucose metabolism and metabolic diseases. Studies also demonstrate that preconditioning with this compound preserves the ATP levels during cardiac ischemia in rats. The molecular mechanisms by which FTY720 promotes metabolism are not well understood. Here, we demonstrate that nanomolar concentrations of the phosphorylated form of FTY720 (FTY720-P), the active ligand of S1P receptor (S1PR), activates mitochondrial respiration and the mitochondrial ATP production rate in AC16 human cardiomyocyte cells. Additionally, FTY720-P increases the number of mitochondrial nucleoids, promotes mitochondrial morphology alterations, and induces activation of STAT3, a transcription factor that promotes mitochondrial function. Notably, the effect of FTY720-P on mitochondrial function was suppressed in the presence of a STAT3 inhibitor. In summary, our results suggest that FTY720 promotes the activation of mitochondrial function, in part, through a STAT3 action.

Discovery of a Promising Fluorine-18 Positron Emission Tomography Radiotracer for Imaging Sphingosine-1-Phosphate Receptor 1 in the Brain

Sphingosine-1-phosphate receptor 1 (S1PR1) is recognized as a novel therapeutic and diagnostic target in neurological disorders. We recently transferred the S1PR1 radioligand [11C]CS1P1 into clinical investigation for multiple sclerosis. Herein, we reported the design, synthesis and evaluation of novel F-18 S1PR1 radioligands. We combined the structural advantages of our two lead S1PR1 radioligands and synthesized 14 new S1PR1 compounds, then performed F-18 radiochemistry on the most promising compounds. Compound 6h is potent (IC50 = 8.7 nM) and selective for S1PR1. [18F]6h exhibited a high uptake in macaque brain (SUV > 3.0) and favorable brain washout pharmacokinetics in positron emission tomography (PET) study. PET blocking and displacement studies confirmed the specificity of [18F]6h in vivo. Radiometabolite analysis confirmed no radiometabolite of [18F]6h entered into the brain to confound the PET measurement. In summary, [18F]6h is a promising radioligand to image S1PR1 and worth translational clinical investigation for humans with brain disorders.

Beneficial Effects of Hordenine on a Model of Ulcerative Colitis

Hordenine, a phenethylamine alkaloid, is found in a variety of plants and exhibits a broad array of biological activities and pharmacological properties, including anti-inflammatory and anti-fibrotic effects. However, the efficacy and underlying mechanisms of hordenine in treating ulcerative colitis (UC) remain unclear. To address this, we examined the therapeutic effects of hordenine on dextran sodium sulphate (DSS)-induced UC by comparing disease activity index (DAI), colon length, secretion of inflammatory factors, and degree of colonic histological lesions across diseased mice that were and were not treated with hordenine. We found that hordenine significantly reduced DAI and levels of pro-inflammatory factors, including interleukin (IL)-6, IL-1β, and tumor necrosis factor alpha (TNF-α), and also alleviated colon tissue oedema, colonic lesions, inflammatory cells infiltration and decreased the number of goblet cells. Moreover, in vitro experiments showed that hordenine protected intestinal epithelial barrier function by increasing the expression of tight junction proteins including ZO-1 and occludin, while also promoting the healing of intestinal mucosa. Using immunohistochemistry and western blotting, we demonstrated that hordenine reduced the expression of sphingosine kinase 1 (SPHK1), sphingosine-1-phosphate receptor 1 (S1PR1), and ras-related C3 botulinum toxin substrate 1 (Rac1), and it inhibited the expression of phosphorylated signal transducer and activator of transcription 3 (p-STAT3) in colon tissues. Thus, hordenine appears to be effective in UC treatment owing to pharmacological mechanisms that favor mucosal healing and the inhibition of SPHK-1/S1PR1/STAT3 signaling.

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.

Conjugated Bile Acids Accelerate Progression of Pancreatic Cancer Metastasis via S1PR2 Signaling in Cholestasis

BACKGROUND

Pancreatic cancer (PC) has an extremely high mortality rate, where obstructive jaundice due to cholestasis is a classic symptom. Conjugated bile acids (CBAs) such as taurocholic acid (TCA) have been reported to activate both the ERK1/2 and AKT signaling pathways via S1P receptor 2 (S1PR2) and promote growth of cholangiocarcinoma. Thus, we hypothesize that CBAs, which accumulate in cholestasis, accelerate PC progression via S1PR2.

METHODS

Murine Panc02-luc and human AsPC-1, MIA PaCa2, and BxPC-3 cells were treated with TCA, S1PR2 agonist CYM5520, S1PR2 antagonist JTE-013, sphingosine-1-phosphate (S1P), and functional S1P receptor antagonist (except S1PR2) FTY720. Bile duct ligation (BDL) was performed on liver implantation or intraperitoneal injection of Panc02-luc cells.

RESULTS

Panc02-luc and AsPC-1 cells predominantly expressed S1PR2, and their growth and migration were stimulated by TCA or CYM5520 in dose-dependent manner, which was blocked by JTE-013. This finding was not seen in PC cell lines expressing other S1P receptors than S1PR2. Panc02-luc growth stimulation by S1P was not blocked by FTY720. BDL significantly increased PC liver metastasis compared with sham. PC peritoneal carcinomatosis was significantly worsened by BDL, confirmed by number of nodules, tumor weight, bioluminescence, Ki-67 stain, ascites, and worse survival compared with sham. CYM5520 significantly worsened PC carcinomatosis, whereas treatment with anti-S1P antibody or FTY720 also worsened progression.

CONCLUSIONS

CBAs accelerated growth of S1PR2 predominant PC both in vitro and in vivo. This finding implicates S1PR2 as a potential therapeutic target in metastatic S1PR2 predominant pancreatic cancer.

Isoliquiritigenin alleviates the development of alcoholic liver fibrosis by inhibiting ANXA2

The study aimed to investigate the effect of isoliquiritigenin (ISL) on model of alcoholic liver fibrosis (ALF). C57BL/6 mice were used to establish animal model of ALF, HSC-T6 cells were used to establish alcohol-activated cell model, and tandem mass tag (TMT) assays were used to analyze the proteome. The results showed that ISL obviously alleviated hepatic fibrosis in model mice. ISL visually improved the area of liver pathological stasis and deposition of fibrillar collagen (Sirius Red staining, Masson staining), inhibited the mRNA expression levels of interleukin 6 (IL-6), tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β) in liver tissues. ISL down-regulated the mRNA expression levels of IL-6 and transforming growth factor-β1(TGF-β1) in activated hepatic stellate cells (HSCs). And ISL significantly reduced annexin A2 (ANXA2) in vitro detected by TMT proteomics technology. Interestingly, it was found for the first time that ISL could inhibit ANXA2 expression both in vivo and in vitro, block the sphingosine kinases (SPHKs)/sphingosine-1-phosphate (S1P)/interleukin 17 (IL-17) signaling pathway and regulate the expression of α-smooth muscle actin (α-SMA) by inhibiting the phosphorylation of signal transducer and activator of transcription 3 (STAT3) at the downstream signal to finally reverse HSCs activation and hepatic fibrosis. Thus, we demonstrated that ISL is a drug monomer with notable anti-hepatic fibrosis activity.

Advances in research on the effectiveness and mechanism of Traditional Chinese Medicine formulas for colitis-associated colorectal cancer

Inflammatory bowel disease (IBD) can progress into colitis-associated colorectal cancer (CAC) through the inflammation-cancer sequence. Although the mechanism of carcinogenesis in IBD has not been fully elucidated, the existing research indicates that CAC may represent a fundamentally different pathogenesis pattern of colorectal cancer. At present, there is no proven safe and effective medication to prevent IBD cancer. In recent years, Chinese medicine extracts and Chinese medicine monomers have been the subject of numerous articles about the prevention and treatment of CAC, but their clinical application is still relatively limited. Traditional Chinese Medicine (TCM) formulas are widely applied in clinical practice. TCM formulas have demonstrated great potential in the prevention and treatment of CAC in recent years, although there is still a lack of review. Our work aimed to summarize the effects and potential mechanisms of TCM formulas for the prevention and treatment of CAC, point out the issues and limitations of the current research, and provide recommendations for the advancement of CAC research in the future. We discovered that TCM formulas regulated many malignant biological processes, such as inflammation-mediated oxidative stress, apoptosis, tumor microenvironment, and intestinal microecology imbalance in CAC, through a review of the articles published in databases such as PubMed, SCOPUS, Web of Science, Embase, and CNKI. Several major signal transduction pathways, including NF-κB, STAT3, Wnt/β-catenin, HIF-1α, and Nrf2, were engaged. TCM formula may be a promising treatment candidate to control the colitis-cancer transformation, however further high-quality research is required.

A novel strategy for precise prognosis management and treatment option in colon adenocarcinoma with TP53 mutations

Background

TP53 is one of the most frequent mutated genes in colon cancer. Although colon cancer with TP53 mutations has a high risk of metastasis and worse prognosis generally, it showed high heterogeneity clinically.

Methods

A total of 1,412 colon adenocarcinoma (COAD) samples were obtained from two RNA-seq cohorts and three microarray cohorts, including the TCGA-COAD (N = 408), the CPTAC-COAD (N = 106), GSE39582 (N = 541), GSE17536 (N = 171) and GSE41258 (N = 186). The LASSO-Cox method was used to establish the prognostic signature based on the expression data. The patients were divided into high-risk and low-risk groups based on the median risk score. The efficiency of the prognostic signature was validated in various cohorts, including TP53-mutant and TP53 wild-type. The exploration of potential therapeutic targets and agents was performed by using the expression data of TP53-mutant COAD cell lines obtained from the CCLE database and the corresponding drug sensitivity data obtained from the GDSC database.

Results

A 16-gene prognostic signature was established in TP53-mutant COAD. The high-risk group had significantly inferior survival time compared to the low-risk group in all TP53-mutant datasets, while the prognostic signature failed to classify the prognosis of COAD with TP53 wild-type properly. Besides, the risk score was the independent poor factor for the prognosis in TP53-mutant COAD and the nomogram based on the risk score was also shown good predictive efficiency in TP53-mutant COAD. Moreover, we identified SGPP1, RHOQ, and PDGFRB as potential targets for TP53-mutant COAD, and illuminated that the high-risk patients might benefit from IGFR-3801, Staurosporine, and Sabutoclax.

Conclusion

A novel prognostic signature with great efficiency was established especially for COAD patients with TP53 mutations. Besides, we identified novel therapeutic targets and potential sensitive agents for TP53-mutant COAD with high risk. Our findings provided not only a new strategy for prognosis management but also new clues for drug application and precision treatment in COAD with TP53 mutations.

Plant-derived compounds for treating autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD), the most common monogenic hereditary kidney disease, is the fourth leading cause of end-stage kidney disease worldwide. In recent years, significant progress has been made in delaying ADPKD progression with different kinds of chemical drugs, such as tolvaptan, rapamycin, and somatostatin. Meanwhile, numerous plant-derived compounds have been investigated for their beneficial effects on slowing ADPKD progression. Among them, saikosaponin-d, Ganoderma triterpenes, curcumin, ginkgolide B, steviol, resveratrol, Sparganum stoloniferum Buch.-Ham, Cordyceps sinensis, triptolide, quercitrin, naringin, cardamonin, gambogic acid, and olive leaf extract have been found to retard renal cyst development by inhibiting cell proliferation or promoting cell apoptosis in renal cyst-lining epithelial cells. Metformin, a synthesized compound derived from French lilac or goat's rue (Galega officinalis), has been proven to retard the progression of ADPKD. This review focuses on the roles and mechanisms of plant-derived compounds in treating ADPKD, which may constitute promising new therapeutics in the future.

Unveiling the biological role of sphingosine-1-phosphate receptor modulators in inflammatory bowel diseases

Inflammatory bowel disease (IBD) is chronic inflammation of the gastrointestinal tract that has a high epidemiological prevalence worldwide. The increasing disease burden worldwide, lack of response to current biologic therapeutics, and treatment-related immunogenicity have led to major concerns regarding the clinical management of IBD patients and treatment efficacy. Understanding disease pathogenesis and disease-related molecular mechanisms is the most important goal in developing new and effective therapeutics. Sphingosine-1-phosphate (S1P) receptor (S1PR) modulators form a class of oral small molecule drugs currently in clinical development for IBD have shown promising effects on disease improvement. S1P is a sphingosine-derived phospholipid that acts by binding to its receptor S1PR and is involved in the regulation of several biological processes including cell survival, differentiation, migration, proliferation, immune response, and lymphocyte trafficking. T lymphocytes play an important role in regulating inflammatory responses. In inflamed IBD tissue, an imbalance between T helper (Th) and regulatory T lymphocytes and Th cytokine levels was found. The S1P/S1PR signaling axis and metabolism have been linked to inflammatory responses in IBD. S1P modulators targeting S1PRs and S1P metabolism have been developed and shown to regulate inflammatory responses by affecting lymphocyte trafficking, lymphocyte number, lymphocyte activity, cytokine production, and contributing to gut barrier function.

Sphingosine kinase activity and sphingosine-1-phosphate in the inflamed human periodontium

OBJECTIVES

This study evaluated changes in the levels of Sphingosine-1-Phosphate (S1P) and Sphingosine Kinase (SPHK) activity in response to non-surgical periodontal treatment in humans.

METHODS

Diseased (n = 65) and healthy sites (n = 72) were screened in 18 patients with localized periodontitis stage II or III. Periodontal clinical parameters were recorded, and the gingival crevicular fluid (GCF) collected at baseline, 30 and 90 days of non-surgical treatment. Internal control sites without attachment loss/bleeding were sampled at baseline and after 90 days of treatment. SPHK activity and S1P levels and SPHK 1/2 isoforms were determined in the GCF at different time points using ELISA.

RESULTS

Non-surgical treatment caused significant improvement in all periodontal clinical parameters (p < 0.01). Activity of SPHK and S1P levels was decreased (p < 0.05) 30 days after treatment and continued up to 90 days (p < 0.01); control sites remained unchanged throughout the study and resembled treated sites at 3 months (p > 0.05). SPHK1 levels presented decrease after periodontal treatment (p < 0.001). SPHK2 levels were lower than SPHK1 (p < 0.001) and remained unchanged.

CONCLUSIONS

S1P levels and SPHK activity decreased within 3 months of non-surgical periodontal treatment, which were correlated with improvements in periodontal parameters. Only SPHK1 levels varied significantly in the states of health and disease.

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.

Crosstalk between pro-survival sphingolipid metabolism and complement signaling induces inflammasome-mediated tumor metastasis

Crosstalk between metabolic and signaling events that induce tumor metastasis remains elusive. Here, we determine how oncogenic sphingosine 1-phosphate (S1P) metabolism induces intracellular C3 complement activation to enhance migration/metastasis. We demonstrate that increased S1P metabolism activates C3 complement processing through S1P receptor 1 (S1PR1). S1P/S1PR1-activated intracellular C3b-α'2 is associated with PPIL1 through glutamic acid 156 (E156) and aspartic acid 111 (D111) residues, resulting in NLRP3/inflammasome induction. Inactivation mutations of S1PR1 to prevent S1P signaling or mutations of C3b-α'2 to prevent its association with PPIL1 attenuate inflammasome activation and reduce lung colonization/metastasis in mice. Also, activation of the S1PR1/C3/PPIL1/NLRP3 axis is highly associated with human metastatic melanoma tissues and patient-derived xenografts. Moreover, targeting S1PR1/C3/PPIL1/NLRP3 signaling using molecular, genetic, and pharmacologic tools prevents lung colonization/metastasis of various murine cancer cell lines using WT and C3a-receptor1 knockout (C3aR1-/-) mice. These data provide strategies for treating high-grade/metastatic tumors by targeting the S1PR1/C3/inflammasome axis.

The Role of the Microbiome on the Pathogenesis and Treatment of Colorectal Cancer

The gut microbiome has long been known to play a role in various aspects of health modulation, including the pathogenesis of colorectal cancer (CRC). With immunotherapy recently emerging as a successful treatment in microsatellite instability high (MSI-high) CRC, and with a newly demonstrated involvement of the gut microbiome in the modulation of therapeutic responses, there has been an explosion of research into the mechanisms of microbial effects on CRC. Harnessing and reprogramming the microbiome may allow for the expansion of these successes to broader categories of CRC, the prevention of CRC in high-risk patients, and the enhancement of standard treatments. In this review, we pull together both well-documented phenomena and recent discoveries that pertain to the microbiome and CRC. We explore the microbial mechanisms associated with CRC pathogenesis and progression, recent advancements in CRC systemic therapy, potential options for diagnosis and prevention, as well as directions for future research.

S1P/S1PR1 signaling differentially regulates the allogeneic response of CD4 and CD8 T cells by modulating mitochondrial fission

Graft-versus-host disease (GVHD) significantly contributes to patient morbidity and mortality after allogeneic hematopoietic cell transplantation (allo-HSCT). Sphingosine-1-phosphate (S1P) signaling is involved in the biogenetic processes of different immune cells. In the current study, we demonstrated that recipient sphingosine kinase 1 (Sphk1), but not Sphk2, was required for optimal S1PR1-dependent donor T-cell allogeneic responses by secreting S1P. Using genetic and pharmacologic approaches, we demonstrated that inhibition of Sphk1 or S1PR1 substantially attenuated acute GVHD (aGVHD) while retaining the graft-versus-leukemia (GVL) effect. At the cellular level, the Sphk1/S1P/S1PR1 pathway differentially modulated the alloreactivity of CD4+ and CD8+ T cells; it facilitated T-cell differentiation into Th1/Th17 cells but not Tregs and promoted CD4+ T-cell infiltration into GVHD target organs but was dispensable for the CTL activity of allogeneic CD8+ T cells. At the molecular level, the Sphk1/S1P/S1PR1 pathway augmented mitochondrial fission and increased mitochondrial mass in allogeneic CD4+ but not CD8+ T cells by activating the AMPK/AKT/mTOR/Drp1 pathway, providing a mechanistic basis for GVL maintenance when S1P signaling was inhibited. For translational purposes, we detected the regulatory efficacy of pharmacologic inhibitors of Sphk1 and S1PR1 in GVHD induced by human T cells in a xenograft model. Our study provides novel mechanistic insight into how the Sphk1/S1P/S1PR1 pathway modulates T-cell alloreactivity and validates Sphk1 or S1PR1 as a therapeutic target for the prevention of GVHD and leukemia relapse. This novel strategy may be readily translated into the clinic to benefit patients with hematologic malignancies and disorders.

S1P/S1PR1 signaling differentially regulates the allogeneic response of CD4 and CD8 T cells by modulating mitochondrial fission

Graft-versus-host disease (GVHD) significantly contributes to patient morbidity and mortality after allogeneic hematopoietic cell transplantation (allo-HSCT). Sphingosine-1-phosphate (S1P) signaling is involved in the biogenetic processes of different immune cells. In the current study, we demonstrated that recipient sphingosine kinase 1 (Sphk1), but not Sphk2, was required for optimal S1PR1-dependent donor T-cell allogeneic responses by secreting S1P. Using genetic and pharmacologic approaches, we demonstrated that inhibition of Sphk1 or S1PR1 substantially attenuated acute GVHD (aGVHD) while retaining the graft-versus-leukemia (GVL) effect. At the cellular level, the Sphk1/S1P/S1PR1 pathway differentially modulated the alloreactivity of CD4⁺ and CD8⁺ T cells; it facilitated T-cell differentiation into Th1/Th17 cells but not Tregs and promoted CD4⁺ T-cell infiltration into GVHD target organs but was dispensable for the CTL activity of allogeneic CD8⁺ T cells. At the molecular level, the Sphk1/S1P/S1PR1 pathway augmented mitochondrial fission and increased mitochondrial mass in allogeneic CD4⁺ but not CD8⁺ T cells by activating the AMPK/AKT/mTOR/Drp1 pathway, providing a mechanistic basis for GVL maintenance when S1P signaling was inhibited. For translational purposes, we detected the regulatory efficacy of pharmacologic inhibitors of Sphk1 and S1PR1 in GVHD induced by human T cells in a xenograft model. Our study provides novel mechanistic insight into how the Sphk1/S1P/S1PR1 pathway modulates T-cell alloreactivity and validates Sphk1 or S1PR1 as a therapeutic target for the prevention of GVHD and leukemia relapse. This novel strategy may be readily translated into the clinic to benefit patients with hematologic malignancies and disorders.

Integrated Metabonomics and Network Pharmacology to Reveal the Action Mechanism Effect of Shaoyao Decoction on Ulcerative Colitis

Background

Traditional Chinese medicine (TCM) has the advantage of multi-component and multi-target, which becomes a hot spot in the treatment of numerous diseases. Shaoyao decoction (SYD) is a TCM prescription, which is mainly used to treat damp-heat dysentery clinically, with small side effects and low cost. However, its mechanism remains elusive. The purpose of this study is to explore the mechanism of SYD in the treatment of mice with ulcerative colitis (UC) induced by dextran sulfate sodium (DSS) through metabolomics and network pharmacology, and verify through molecular docking and immunohistochemistry, so as to provide a scientific basis for the role of SYD in the treatment of UC.

Materials and Methods

Firstly, DSS-induced UC models were established and then untargeted metabolomics analysis of feces, livers, serum and urine was performed to determine biomarkers and metabolic pathways closely related to the role of SYD. Besides, network pharmacology was applied to screen the active components and UC-related targets, which was verified by molecular docking. Finally, metabonomics and network pharmacology were combined to draw the metabolite-pathway-target network and verified by immunohistochemistry.

Results

Metabolomics results showed that a total of 61 differential metabolites were discovered in SYD-treated UC with 3 main metabolic pathways containing glycerophospholipid metabolism, sphingolipid metabolism and biosynthesis of unsaturated fatty acids, as well as 8 core targets involving STAT3, IL1B, IL6, IL2, AKT1, IL4, ICAM1 and CCND1. Molecular docking demonstrated that the first five targets had strong affinity with quercetin, wogonin, kaempferol and baicalein. Combined with metabolomics and network pharmacology, sphingolipid signaling pathway, PI3K/AKT-mTOR signaling pathway and S1P3 pathway were identified as the main pathways.

Conclusion

SYD can effectively ameliorate various symptoms and alleviate intestinal mucosal damage and metabolic disorder in DSS induced UC mice. Its effect is mainly related to sphingolipid metabolism, PI3K/AKT-mTOR signaling pathway and S1P3 pathway.

Targeting SPHK1/PBX1 Axis Induced Cell Cycle Arrest in Non-Small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) accounts for 85~90% of lung cancer cases, with a poor prognosis and a low 5-year survival rate. Sphingosine kinase-1 (SPHK1), a key enzyme in regulating sphingolipid metabolism, has been reported to be involved in the development of NSCLC, although the underlying mechanism remains unclear. In the present study, we demonstrated the abnormal signature of SPHK1 in NSCLC lesions and cell lines of lung cancers with a potential tumorigenic role in cell cycle regulation. Functionally, ectopic Pre-B cell leukemia homeobox-1 (PBX1) was capable of restoring the arrested G1 phase induced by SPHK1 knockdown. However, exogenous sphingosine-1-phosphate (S1P) supply had little impact on the cell cycle arrest by PBX1 silence. Furthermore, S1P receptor S1PR3 was revealed as a specific switch to transport the extracellular S1P signal into cells, and subsequently activated PBX1 to regulate cell cycle progression. In addition, Akt signaling partially participated in the SPHK1/S1PR3/PBX1 axis to regulate the cell cycle, and the Akt inhibitor significantly decreased PBX1 expression and induced G1 arrest. Targeting SPHK1 with PF-543 significantly inhibited the cell cycle and tumor growth in preclinical xenograft tumor models of NSCLC. Taken together, our findings exhibit the vital role of the SPHK1/S1PR3/PBX1 axis in regulating the cell cycle of NSCLC, and targeting SPHK1 may develop a therapeutic effect in tumor treatment.

Lipidomic insights into the immune response and pearl formation in transplanted pearl oyster Pinctada fucata martensii

During pearl culture, the excess immune responses may induce nucleus rejection and death of pearl oysters after transplantation. To better understand the immune response and pearl formation, lipidomic analysis was applied to investigate changes in the serum lipid profile of pearl oyster Pinctada fucata martensii following transplantation. In total, 296 lipid species were identified by absolute quantitation. During wound healing, the content of TG and DG initially increased and then decreased after 3 days of transplantation with no significant differences, while the level of C22:6 decreased significantly on days 1 and 3. In the early stages of transplantation, sphingosine was upregulated, whereas PC and PUFAs were downregulated in transplanted pearl oyster. PI was upregulated during pearl sac development stages. GP and LC-PUFA levels were upregulated during pearl formation stage. In order to identify enriched metabolic pathways, pathway enrichment analysis was conducted. Five metabolic pathways were found significantly enriched, namely glycosylphosphatidylinositol-anchor biosynthesis, glycerophospholipid metabolism, alpha-linolenic acid metabolism, linoleic acid metabolism and arachidonic acid metabolism. Herein, results suggested that the lipids involved in immune response, pearl sac maturation, and pearl formation in the host pearl oyster after transplantation, which might lead to an improvement in the survival rate and pearl quality of transplanted pearl oyster.

Diacerein attenuate LPS-induced acute lung injury via inhibiting ER stress and apoptosis: Impact on the crosstalk between SphK1/S1P, TLR4/NFκB/STAT3, and NLRP3/IL-1β signaling pathways

AIMS

Acute lung injury (ALI) is a life-threatening clinical problem with high mortality rate and limited treatments or preventive options that represents a major challenge for clinicians. Diacerein (DIA) is a multi-target anthraquinone derivative with potent anti-inflammatory action. The aim of this study is to assess the protective effect of DIA and its potential molecular targets against lipopolysaccharide (LPS)-induced ALI in rats.

MATERIALS AND METHODS

Adult male Sprague-Dawley rats were orally administrated DIA (50 mg/kg) for 5 consecutive days followed by a single intraperitoneal injection of LPS (5mg/kg).

KEY FINDINGS

DIA mitigated oxidative lung injury in LPS-challenged rats via significantly decreasing lung wet/dry (W/D) ratio, inflammatory cells infiltration, and lipid peroxidation, with concomitant elevation in enzymatic and non-enzymatic antioxidant levels in lung tissue. Likewise, DIA alleviated endoplasmic reticulum stress and markedly halted inflammation triggered by LPS challenge in pulmonary tissue by suppressing NLRP3/IL-1β and TLR4/NF-κB signaling with parallel decrease in proinflammatory cytokine levels. Interestingly, DIA down regulated Sphk1/S1P axis, reduced GSK-3β and STAT3 proteins expression, and markedly decreased caspase-3 besides increasing Bcl-2 levels in lung tissue of LPS-challenged animals. These biochemical findings was simultaneously associated with marked improvement in histological alterations of lung tissue.

SIGNIFICANCE

These findings verify the protective effect of DIA against LPS-induced ALI through targeting oxidative stress, endoplasmic reticulum stress, and apoptosis. Importantly, DIA halted the hyperinflammatory state triggered by LPS via multi-faceted inhibitory effect on different signaling pathways, hence DIA could potentially reduce mortality in patients with ALI.

The therapeutic effects of cycloastragenol in ulcerative colitis by modulating SphK/MIP-1α/miR-143 signalling

Patients with ulcerative colitis (UC) experience diarrhoea, hematochezia, and abdominal pain. UC is a well-known health challenge affecting 200-250 per 100,000 individuals worldwide, with a similar prevalence in both sexes and elevated upon activation of gut immune responses. We evaluated the potential therapeutic effects of cycloastragenol in experimentally-induced UC rats and examined the modulation of sphingosine kinase (SphK), macrophage inflammatory protein (MIP)-1α, and miR-143. We treated UC rats with 30 mg/kg cycloastragenol and assessed gene and protein expression levels of SphK, MIP-1α, B-cell lymphoma 2 (BCL2), BCL2-associated X (BAX), miR-143, NF-κB, tumour necrosis factor (TNF)-α, and active caspase-3. Colon sections were examined using electron microscopy; additional sections were stained with hematoxylin-eosin or immunostained with anti-TNF-α and anti-caspase-3 antibodies. Electron microscopy of UC specimens revealed dark distorted goblet cell nuclei with disarranged mucus granules and a non-distinct brush border with atypical microvilli. Hematoxylin-eosin staining showed damaged intestinal glands, severe hemorrhage, and inflammatory cell infiltration. Cycloastragenol treatment improved the induced morphological changes. In UC rats, cycloastragenol significantly reduced expression levels of SphK, MIP-1α, BAX, NF-κB, TNF-α, and active caspase-3, associated with BCL2 and miR-143 overexpression. Therefore, cycloastragenol protects against UC by modulating SphK/MIP-1α/miR-143, subsequently deactivating inflammatory and apoptotic pathways.

Colorectal Cancer in Ulcerative Colitis: Mechanisms, Surveillance and Chemoprevention

Patients with ulcerative colitis (UC) are at a two- to three-fold increased risk of developing colorectal cancer (CRC) than the general population based on population-based data. UC-CRC has generated a series of clinical problems, which are reflected in its worse prognosis and higher mortality than sporadic CRC. Chronic inflammation is a significant contributor to the development of UC-CRC, so comprehending the relationship between the proinflammatory factors and epithelial cells together with downstream signaling pathways is the core to elucidate the mechanisms involved in developing of CRC. Clinical studies have shown the importance of early prevention, detection and management of CRC in patients with UC, and colonoscopic surveillance at regular intervals with multiple biopsies is considered the most effective way. The use of endoscopy with targeted biopsies of visible lesions has been supported in most populations. In contrast, random biopsies in patients with high-risk characteristics have been suggested during surveillance. Some of the agents used to treat UC are chemopreventive, the effects of which will be examined in cancers in UC in a population-based setting. In this review, we outline the current state of potential risk factors and chemopreventive recommendations in UC-CRC, with a specific focus on the proinflammatory mechanisms in promoting CRC and evidence for personalized surveillance.