Greasing the Wheels of the Cancer Machine: The Role of Lipid Metabolism in Cancer

Uncovering the protective role of lipid droplet accumulation against acid-induced oxidative stress and cell death in osteosarcoma

Extracellular acidosis stemming from altered tumor metabolism promotes cancer progression by enabling tumor cell adaptation to the hostile microenvironment. In osteosarcoma, we have previously shown that acidosis increases tumor cell survival alongside substantial lipid droplet accumulation. In this study, we explored the role of lipid droplet formation in mitigating cellular stress induced by extracellular acidosis in osteosarcoma cells, thereby enhancing tumor survival during progression. Specifically, we examined how lipid droplets shield against reactive oxygen species induced by extracellular acidosis. We demonstrated that lipid droplet biogenesis is critical for acid-exposed tumor cell survival, as it starts shortly after acid exposure (24 h) and inversely correlates with ROS levels (DCFH-DA assay), lipid peroxidation (Bodipy assay), and the antioxidant response, as also revealed by NRF2 transcript. Additionally, extracellular metabolites, such as lactate, and interaction with mesenchymal stromal cells within the tumor microenvironment intensify lipid droplet build-up in osteosarcoma cells. Critically, upon targeting two key proteins implicated in LD formation - PLIN2 and DGAT1 - cell viability significantly declined while ROS production escalated. In summary, our findings underscore the vital reliance of acid-exposed tumor cells on lipid droplet formation to scavenge oxidative stress. We conclude that the rewiring of lipid metabolism driven by microenvironmental cues is of paramount importance for the survival of metabolically altered osteosarcoma cells in acidic condition. Overall, we suggest that targeting key members of lipid droplet biogenesis may eradicate more aggressive and resistant tumor cells, uncovering potential new treatment strategies for osteosarcoma.

iPLA2β regulates the dual effects of arachidonic acid in thyroid cancer

BACKGROUND

Abnormal arachidonic acid metabolism in the tumor microenvironment is closely related to cancer progression; however, thyroid cancer was rarely researched.

METHODS

Through lipidomic analysis, we disclosed that dysregulated arachidonic acid metabolism plays dual effects on thyroid cancer. The promoting role of arachidonic acid in the progression of thyroid cancer cells was evaluated utilizing cell viability (CCK-8 assay) and transwell invasion assays, confirmed by corresponding inhibitors. Lipid peroxidation and the use of various cell death inhibitors confirmed that arachidonic acid confers vulnerability to ferroptosis in thyroid cancer. The roles of arachidonic acid and ferroptosis inducer in thyroid cancer were assessed in a xenograft mouse model.

RESULTS

On one hand, arachidonic acid promotes the progression of thyroid cancer through the cyclooxygenase/prostaglandin pathway; on another hand, arachidonic acid confers vulnerability to ferroptosis through lipoxygenases. Moreover, iPLA2β drives converse roles of arachidonic acid between cancer-progression and ferroptosis vulnerability through releasing free arachidonic acid from the cell membrane. Finally, we confirmed high arachidonic acid diet promotes the development of thyroid cancer in vivo, whereas ferroptosis inducer sulfasalazine dramatically reduced tumor growth of mice with feeding arachidonic acid.

CONCLUSIONS

Our research demonstrated the roles of iPLA2β in conversing dual effects of arachidonic acid in thyroid cancer and provides ferroptosis inducer as a potential therapeutic strategy.

Integrative microbiomics, proteomics and lipidomics studies unraveled the preventive mechanism of Shouhui Tongbian Capsules on cerebral ischemic stroke injury

ETHNOPHARMACOLOGICAL RELEVANCE

Cerebral ischemic stroke (CIS) is one of the most important factors leading to death and disability, which seriously threaten the survival and health of patients. The intentional flora and its derived metabolites are demonstrated to play vital roles in the physiology and onset of CIS. Shouhui Tongbian Capsules (SHTB), a Traditional Chinese Medicine, could regulate gut microbiota and metabolites. Study has found that SHTB has protective effect on CIS, but the mechanism is still unclear.

AIM OF STUDY

This study was designed to evaluate the preventive effects and the mechanism of SHTB on CIS injury.

MATERIALS AND METHODS

The rats were pretreated with SHTB for 5 days, then the middle cerebral artery occlusion/reperfusion (MCAO/R) was established. Neurological deficit score, TTC staining, brain water content, H&E and Nissl staining were preformed to evaluate the preventive effects of SHTB on CIS. The Occludin and ZO-1 were analyzed to evaluate the blood-brain barrier (BBB). 16S rDNA sequencing and LC-ESI-MS/MS-based metabolomics profiling were performed to analyze the gut microbiota composition and short chain fatty acids (SCFAs) profile in gut. Serum lipopolysaccharide specific IgA antibody (LPS-SIgA) and diamine oxidase (DAO), as well as colon Claudin 5 and ZO-1 were analyzed to evaluate the intestinal barrier. Proteomics was used to evaluated the proteins profile in brain. Lipidomics were used to evaluate the brain SCFAs as well as medium and long chain fatty acids (MCFAs and LCFAs). Malondialdehyde (MDA), Total Superoxide dismutase (T-SOD), Glutathione (GSH), Glutathione peroxidase (GSH-Px), Catalase (CAT) and reactive oxygen species (ROS) were assayed to evaluate the oxidative stress in brain. Western blot was performed to evaluate the expression of PPARγ, Nrf2, SLC3A2, SCL7A11, GPX4, ACSL4 and LOX.

RESULTS

SHTB prevented rats from MCAO/R injury, which was confirmed by lower cerebral infarct rate, brain water content, neurological deficit score and nissl body loss, and improved brain pathology. Meanwhile, SHTB upregulated the expression of ZO-1 and Occludin to maintain the integrity of BBB. 16S rDNA sequencing and LC-ESI-MS/MS-based targeted metabolomics found that SHTB increased the abundance of gut microbiota, regulated the numbers of intestinal bacteria to increase the production of Acetic acid, Propionic acid, and Butyric acid, as well as decrease the production of Valeric acid and Hexanoic acid in the gut. Meanwhile, SHTB improved the intestinal barrier by upregulating the protein levels of Claudin 5 and ZO-1, which was confirmed by low concentrations of LPS-SIgA and DAO in serum. Multi omics and spearman correlation analysis indicated that SHTB regulated the abundance of Escherichia-Shigella and Lactobacillus to increase Acetic acid, Propionic acid, and Butyric acid to induce the expression of PPARγ, thereby regulating fatty acid metabolism and degradation, improving lipid metabolism disorders, downregulating lipid oxidative stress, inhibiting ferroptosis, and alleviating brain injury.

CONCLUSION

This study confirmed that SHTB improved the disturbance of fatty acid metabolism in brain tissue by regulating gut microbiota and the production of fecal SCFAs to inhibit ferroptosis caused by lipid oxidative stress and prevent CIS injury, which provided a potential candidate drug for the prevention of CIS.

Lipid metabolism in ferroptosis: Unraveling key mechanisms and therapeutic potential in cancer

Ferroptosis, a form of iron-dependent cell death driven by lipid peroxidation, has emerged as a critical area of research for cancer therapy. This review delves into the intricate relationship between lipid metabolism and ferroptosis, emphasizing the impact of lipidome remodeling on cancer cell susceptibility. We explore key mechanisms, such as the role of polyunsaturated fatty acids and phosphatidylethanolamines in ferroptosis induction, alongside the protective effects of monounsaturated fatty acids and their regulatory enzymes. We also discuss the influence of dietary fatty acids, lipid droplets, and the epithelial-to-mesenchymal transition on ferroptosis and cancer resistance. By integrating current findings on enzymatic regulation, lipid peroxidation pathways, and metabolic adaptations, this review highlights potential therapeutic strategies targeting lipid metabolism to enhance ferroptosis-based cancer treatments. Our goal is to provide a comprehensive overview that underscores the significance of lipid metabolic pathways in ferroptosis and their implications for developing novel cancer therapies.

RNF5 exacerbates steatotic HCC by enhancing fatty acid oxidation via the improvement of CPT1A stability

Non-alcoholic fatty liver disease (NAFLD) is expected to become the leading risk factor for liver cancer, surpassing viral hepatitis. Unlike viral hepatitis-related hepatocellular carcinoma (HCC), the role of excessive nutrient supply in steatotic HCC is not well understood, hindering effective prevention and treatment strategies. Therefore, it is crucial to identify key molecules in the pathogenesis of steatotic HCC, investigate changes in metabolic reprogramming due to excessive fatty acid (FA) supply, understand its molecular mechanisms, and find potential therapeutic targets. Trans-species transcriptome analysis identified Ring Finger Protein 5 (RNF5) as a critical regulator of steatotic HCC. RNF5 upregulation is associated with poor prognosis in steatotic HCC compared to canonical HCC. In vitro and in vivo studies showed that RNF5 exacerbates HCC in the presence of additional FA supply. Lipidomics and transcriptome analyses revealed that RNF5 significantly increases carnitine palmitoyltransferase 1A (CPT1A) mRNA levels and is positively correlated with fatty acid oxidation (FAO). Protein interaction analysis demonstrated that RNF5 promotes K63-type ubiquitination of insulin-like growth factor-2 mRNA-binding protein 1 (IGF2BP1), enhancing CPT1A mRNA stabilization through m6A modification. Additionally, peroxisome proliferator-activated receptor gamma (PPARγ) was found to activate RNF5 expression specifically in HCC cells. Mechanistically, excessive exogenous FAs reorganize FA metabolism in HCC cells, worsening steatotic HCC via the PPARγ-RNF5-IGF2BP1-CPT1A axis. This study highlights a distinct FA metabolism pattern in steatotic HCC, providing valuable insights for potential therapeutic targets.

Lipid droplet formation induced by icaritin derivative IC2 promotes a combination strategy for cancer therapy

BACKGROUND

Lipid metabolism is crucial in cancer progression. Lipid droplets (LDs) generated in cancer cells can act as protective mechanisms through alleviating lipotoxicity under stress conditions. We previously developed IC2 from the Chinese medicine icaritin as an inhibitor of stearoyl-CoA desaturase 1 (SCD1). IC2 has been shown to disrupt lipid metabolism and inhibits cancer cell proliferation. However, the impact of IC2 on intracellular LDs and the potential of targeting LD formation for combination cancer therapy remain unexplored.

METHODS

LD formation in cancer cells was analyzed with oil red O or BODIPY staining by microscopy. LD quantification was normalized to the cell number. IC2-induced cellular responses were revealed by transcriptional analysis, real-time PCR, and immunoblotting. Mitochondrial functions were assessed by measuring ATP production and oxygen consumption. The lipid source for LD formation was studied using lipid transporter inhibitors or lipid deprivation. The effect of inhibiting LD formation on IC2's anti-tumor effects was evaluated using MTT assays and apoptosis assays, which was subsequently validated in an in vivo xenografted tumor model.

RESULTS

IC2 exerted anti-tumor effects, resulting in LD formation in various cancer cells. LD formation stimulated by IC2 was independent of extracellular lipid sources and did not result from increased de novo fatty acid (FA) synthesis within the cancer cells. Transcriptional analysis indicated that IC2 disturbed mitochondrial functions, which was confirmed by impaired mitochondrial membrane potential (MMP) and reduced capacity for ATP production and oxygen consumption. Moreover, IC2 treatment led to a greater accumulation of lipids in LDs outside the mitochondria compared with the control group. IC2 inhibited the proliferation of PC3 cells and promoted the apoptosis of the cancer cells. These effects were further enhanced after inhibiting the diacylglycerol acyltransferase 1 (DGAT1), a key intracellular enzyme involved in LD formation. In PC3-xenografted mice, the DGAT1 inhibitor augmented the IC2-induced reduction in tumor growth by modulating LD formation.

CONCLUSION

LD formation is a feedback response to IC2's anti-tumor effects, which compromises the anti-tumor actions. IC2's anti-tumor efficacy can be enhanced by combining it with inhibitors targeting LD formation. This strategy may be extended to other anti-tumor agents that regulate lipid metabolism.

Ferredoxin 2 is critical for tumor suppression and lipid homeostasis but dispensable for embryonic development

Ferredoxin 1 and 2 (FDX1/2) constitute an evolutionarily conserved FDX family of iron-sulfur cluster (ISC) containing proteins. FDX1/2 are cognate substrates of ferredoxin reductase (FDXR) and serve as conduits for electron transfer from NADPH to a set of proteins involved in biogenesis of steroids, hemes, ISC and lipoylated proteins. Recently, we showed that Fdx1 is essential for embryonic development and lipid homeostasis. To explore the physiological role of FDX2, we generated Fdx2-deficient mice. Interestingly, we found that unlike Fdx1-null embryos, which were dead at embryonic day 10.5 to 13.5, Fdx2-null mice were viable. We also found that both Fdx2-null and Fdx2-heterozygous mice had a short lifespan and were susceptible to spontaneous tumors and steatohepatitis. Moreover, we found that FDX2-deficiency increased whereas overexpression of FDX2 decreased cytoplasmic accumulation of lipid droplets. Consistently, we found that FDX2 deficiency led to accumulation of cholesterol and triglycerides. Mechanistically, we found that FDX2 deficiency suppressed expression of cholesterol transporter ABCA1 and activated master lipid transcription regulators SREBP1/2, thus leading to altered lipid metabolism. Untargeted lipidomic analysis showed that FDX2 deficiency led to altered biosynthesis of various lipid classes, including cardiolipins, cholesterol, ceramides, triglycerides, and fatty acids. In summary, our findings underscore an indispensable role of FDX2 in tumor suppression and lipid homeostasis at both cellular and organismal levels without being a prerequisite for embryonic development.

Identification and dissection of prostate cancer grounded on fatty acid metabolism-correlative features for predicting prognosis and assisting immunotherapy

BACKGROUND

Fatty acid metabolism (FAM) plays a critical role in tumor progression and therapeutic resistance by enhancing lipid biosynthesis, storage, and catabolism. Dysregulated FAM is a hallmark of prostate cancer (PCa), enabling cancer cells to adapt to extracellular signals and metabolic changes, with the tumor microenvironment (TME) playing a key role. However, the prognostic significance of FAM in PCa remains unexplored.

METHODS

We analyzed 309 FAM-related genes to develop a prognostic model using least absolute shrinkage and selection operator (LASSO) regression based on The Cancer Genome Atlas (TCGA) database. This model stratified PCa patients into high- and low-risk groups and was validated using the Gene Expression Omnibus (GEO) database. We constructed a nomogram incorporating risk score, clinical variables (T and N stage, Gleason score, age), and assessed its performance with calibration curves. The associations between risk score, tumor mutation burden (TMB), immune checkpoint inhibitors (ICIs), and TME features were also examined. Finally, a hub gene was identified via protein-protein interaction (PPI) networks and validated.

RESULTS

The risk score was an independent prognostic factor for PCa. High-risk patients showed worse survival outcomes but were more responsive to immunotherapy, chemotherapy, and targeted therapies. A core gene with high expression correlated with poor prognosis, unfavorable clinicopathological features, and immune cell infiltration.

CONCLUSION

These findings reveal the prognostic importance of FAM in PCa, providing novel insights into prognosis and potential therapeutic targets for PCa management.

Lipidomics-driven drug discovery and delivery strategies in glioblastoma

With few viable treatment options, glioblastoma (GBM) is still one of the most aggressive and deadly types of brain cancer. Recent developments in lipidomics have demonstrated the potential of lipid metabolism as a therapeutic target in GBM. The thorough examination of lipids in biological systems, or lipidomics, is essential to comprehending the changed lipid profiles found in GBM, which are linked to the tumor's ability to grow, survive, and resist treatment. The use of lipidomics in drug delivery and discovery is examined in this study, focusing on how it may be used to find new biomarkers, create multi-target directed ligands, and improve drug delivery systems. We also cover the use of FDA-approved medications, clinical trials that use lipid-targeted medicines, and the integration of lipidomics with other omics technologies. This study emphasizes lipidomics as a possible tool in developing more effective treatment methods for GBM by exploring various lipid-centric techniques.

Blood lipid metabolic biomarkers are emerging as significant prognostic indicators for survival in cancer patients

BACKGROUND

Dyslipidemia is a common comorbidity in patients with cancer, yet the impact of abnormal lipid levels on tumor prognosis remains contentious. This study was conducted to synthesize the current evidence regarding the prognostic utility of blood lipid levels, including high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglycerides (TG), apolipoprotein A1 (ApoA1), and apolipoprotein B (ApoB), in predicting overall survival (OS) and disease-free survival (DFS) in cancer patients.

METHODS

A comprehensive literature search was performed across electronic databases to assess the associations between blood lipid levels and OS or DFS in cancer patients. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated to analyze the data. The research protocol was previously submitted to the International Prospective Register of Systematic Reviews (PROSPERO): CRD42023458597.

RESULTS

Our study represents the largest and most extensive evaluation of the prognostic significance of blood lipid levels in cancer to date. It includes a meta-analysis of 156 eligible studies involving 85,173 cancer patients. The findings revealed a significant association between elevated levels of HDL-C, TC, and ApoA1 and improved OS and DFS in cancer patients. In contrast, no significant relationships were identified between LDL-C, TG, and ApoB levels and the OS or DFS of cancer patients.

CONCLUSION

Blood lipids, particularly HDL-C, TC, and ApoA1, emerge as accessible and cost-effective biomarkers that may aid in assessing survival outcomes in cancer patients and potentially inform clinical decision-making.

Metabolic targeting of neuroblastoma, an update

Neuroblastoma is a paediatric cancer of the sympathetic nervous system that originates from the neural crest and can be categorised into stages and risk groups. Risk groups inform treatment options and high-risk cases bear a 50 % probability of relapse post-treatment remission. In neuroblastoma, MYCN amplification is the strongest predictor of unfavourable patient prognosis; circa 50 % of high-risk cases display MYCN amplification. This dismal prognosis is perhaps influenced by the MYCN-driven metabolic rewiring of these cells since the MYC family is indicated in the regulation of proliferation, cell death, metabolism, differentiation, and protein synthesis. This review aims to capture the most recent studies that investigate metabolic rewiring in MYCN-amplified and MYCN-activated cells from the perspective of alterations to glycolysis, the TCA cycle, and oxidative phosphorylation, in addition to changes to amino acid, nucleotide, and lipid metabolism that can be relevant to therapy. A better understanding of the metabolic profile of MYCN-amplified disease will facilitate the identification of effective treatment options and improve the prognosis of high-risk neuroblastoma patients.

Targeting lipid metabolism via nanomedicine: A prospective strategy for cancer therapy

Lipid metabolism has been increasingly recognized to play an influencing role in tumor initiation, progression, metastasis, and therapeutic drug resistance. Targeting lipid metabolic reprogramming represents a promising therapeutic strategy. Despite their structural complexity and poor targeting efficacy, lipid-metabolizing drugs, either used alone or in combination with chemotherapeutic agents, have been employed in clinical practice. The advent of nanotechnology offers new approaches to enhancing therapeutic effects, includingthe targeted delivery and integration of lipid metabolic reprogramming with chemotherapy, photodynamic therapy (PDT), and immunotherapy. The integrated nanoformulation, nanomedicine, could significantly advance the field of lipid metabolism therapy. In this review, we will briefly introduce the concept of cancer lipid metabolism reprogramming, then elaborate the latest advances in engineered nanomedicine for targeting lipid metabolism during cancer treatment, and finally provide our insights into future perspectives of nanomedicine for interference with lipid metabolism in the tumor microenvironment.

Cholesterol: The driving force behind the remodeling of tumor microenvironment in colorectal cancer

Essential membrane components and metabolites with a wide range of biological roles are both produced by cholesterol metabolism. Cell-intrinsic and cell-extrinsic stimuli alter cholesterol metabolism in the tumor microenvironment (TME), which in turn encourages colorectal carcinogenesis. Metabolites produced from cholesterol play intricate roles in promoting the development of colorectal cancer (CRC) and stifling immunological responses. By altering the extracellular matrix of the main tumor, redesigning its immunological environment, and altering its mechanical stiffness, cholesterol can encourage the epithelial-mesenchymal transition of the primary tumor, opening up a pathway for tumor metastasis. Its functions in TME remodeling and tumor prevention have been recently identified. In this review we address the function of cholesterol in TME remodeling and therapeutic techniques designed to block cholesterol metabolism, and discuss how combining these strategies with already available anti-CRC medicines can have combined effects and open up new therapeutic avenues.

Adipocyte-derived fatty acid uptake induces obesity-related breast cancer progression: a review

Obesity is a metabolic disorder that occurs when excess energy taken into the body is stored as fat. It is known that this metabolic imbalance affects the development of other diseases such as cancer, cardiovascular diseases, insulin resistance, and diabetes. The main cellular component of adipose tissue is adipocytes, and the environmental interactions of adipocytes are important to study the mechanism of disorder formation. Breast tissue is rich in adipose tissue and obesity is known to be an important risk factor in the development of breast cancer. Altered adipogenesis and lipogenesis processes in adipocytes in breast tissue support tumor development through the transfer of fatty acids released from adipocytes. We believe that blending adipocyte biology with breast cancer development is important for investigating the mechanisms that regulate breast tumor malignant behavior and providing new targets for treatment. Fatty acids, which are an energy source for breast cancer cells, are discussed from molecular perspectives in this review.

Tumor-derived miR-9-5p-loaded EVs regulate cholesterol homeostasis to promote breast cancer liver metastasis in mice

Cancer cells secrete extracellular vesicles (EV) encapsulating bioactive cargoes to facilitate inter-organ communication in vivo and are emerging as critical mediators of tumor progression and metastasis, a condition which is often accompanied by a dysregulated cholesterol metabolism. Whether EVs are involved in the control of cholesterol homeostasis during tumor metastasis is still undefined and warrant further investigation. Here, we find that breast cancer-derived exosomal miR-9-5p induces the expression of HMGCR and CH25H, two enzymes involved in cholesterol synthesis and the conversion of 25-hydroxycholesterol from cholesterol by targeting INSIG1, INSIG2 and ATF3 genes in the liver. Notably, in vivo miR-9-5p antagomir treatment and genetic CH25H ablation prevents tumor metastasis in a mouse model of breast cancer. Thus, our findings reveal the regulatory mechanism of tumor-derived miR-9-5p in liver metastasis by linking oxysterol metabolism and Kupffer cell polarization, shedding light on future applications for cancer diagnosis and treatment.

Activated PARP1/FAK/COL5A1 signaling facilitates the tumorigenesis of cholesterol-resistant ovarian cancer cells through promoting EMT

Cancer cells require plentiful cholesterol for membrane biogenesis and other functional needs due to fast proliferating, leading to the interaction of cholesterol or its metabolites with cancer-related pathways. However, the impact of long-lasting high cholesterol concentrations on tumorigenesis and its underlying mechanisms remains largely unexplored. To the best of our knowledge, this study is the first to establish a cholesterol-resistant ovarian cancer cells, whose intracellular total cholesterol level up to 6-8 mmol/L. We confirmed that high cholesterol facilitated the progression of ovarian cancer in vitro and in vivo. Notably, our findings revealed significant upregulation of collagen type V alpha 1 chain (COL5A1) expression in cholesterol-resistant ovarian cancer cells and human ovarian cancer tissue, which was depended on FAK/Src activation. Mechanistically, PARP1 directly bound to FAK in response to activate FAK/Src/COL5A1 signaling. Intriguingly, COL5A1 depletion significantly impeded the tumorigenesis of these cells, concomitant with a decrease in epithelial-mesenchymal transition (EMT) progression. In conclusion, PARP1/FAK/COL5A1 signaling activation facilitated progression of cholesterol-resistant ovarian cancer cells by promoting EMT, thereby broadening a new therapeutic opportunity.

Lipids and adipocytes involvement in tumor progression with a focus on obesity and diet

The adipose tissue is a complex organ that can play endocrine, metabolic, and immune regulatory roles in cancer. In particular, adipocytes provide metabolic substrates for cancer cell proliferation and produce signaling molecules that can stimulate cell adhesion, migration, invasion, angiogenesis, and inflammation. Cancer cells, in turn, can reprogram adipocytes towards a more inflammatory state, resulting in a vicious cycle that fuels tumor growth and evolution. These mechanisms are enhanced in obesity, which is associated with the risk of developing certain tumors. Diet, an exogenous source of lipids with pro- or anti-inflammatory functions, has also been connected to cancer risk. This review analyzes how adipocytes and lipids are involved in tumor development and progression, focusing on the relationship between obesity and cancer. In addition, we discuss how diets with varying lipid intakes can affect the disease outcomes. Finally, we introduce novel metabolism-targeted treatments and adipocyte-based therapies in oncology.

Ether-Linked Glycerophospholipids Are Potential Chemo-Desensitisers and Are Associated With Overall Survival in Carcinoma Patients

Lipid reprogramming in carcinoma is reported to have a role in carcinogenesis, prognosis and therapy response. The lipid reprogramming could be contributed by either autonomous or nonautonomous resources. Since the nonautonomous lipid resources contributed by lipoproteins and their receptors have been reported in epithelial ovarian cancer (EOC), the impact of autonomous lipid metabolites was unknown. This report revealed a unique lipid class, ether-linked phosphatidyl-ethanolamine (PE O-), which enhances chemo-insensitivity and progression in EOC and potentially cross carcinomas. Analysis of CCLEC/GDSCC database and in-house cell line lipidomes identified PE O- as the major lipid associated with cisplatin/paclitaxel sensitivity. In the testing of PE O- effect on cancer phenotypes, it enhanced cell growth, migratory activities and promoted cisplatin/paclitaxel insensitivity. In addition, treating AGPS inhibitor-sensitised chemo-cytotoxic upon cisplatin/paclitaxel treatments. Treating PE O- could reverse AGPS inhibitor chemosensitisation effect on EOC cells. At last, using TCGA-EOC transcriptome database, the PE O- related gene expressions were positive correlated with patient prognosis in general, or in whom were treated with platin- or taxel-based chemotherapies. The expressions of genes for the synthesis of PE O- aggravates therapy response in EOC patients. PE O- facilitates human carcinoma cell line growth, mobility and chemo-insensitivity.

CCDC71L as a novel prognostic marker and immunotherapy target via lipid metabolism in head and neck squamous cell carcinoma

BACKGROUND

Head and neck squamous cell carcinoma (HNSCC) is the sixth most widespread cancer globally with high rate and poor prognosis. Coiled-coil domain containing 71 like (CCDC71L) exerts an important role in cellular lipid metabolic process. However, its function in HNSCC remains unclear. To this end, we examined the CCDC71L implications for prognosis and tumor microenvironment in HNSCC.

MATERIALS AND METHODS

First, CCDC71L expression was explored through The Cancer Genome Atlas (TCGA), Human Protein Atlas (HPA), the Gene Expression Profiling Interactive Analysis 2 (GEPIA2), Clinical Proteomic Tumor Analysis Consortium (CPTAC) and the Gene Expression Omnibus (GEO) databases. The clinicpathological information were obtained from the dataset of TCGA. The Kaplan-Meier Plotter databases and Cox model were performed for the determination of prognostic values of CCDC71L, including the overall survival (OS), progress free interval (PFI), recurrence-free survival (RFS) and disease specific survival (DSS). Then, the potential mechanism of CCDC71L in HNSCC development was elucidated by means of Gene set enrichment analysis (GSEA) and Metascape databases. Furthermore, the relevance of CCDC71L to immune cells infiltration and immune checkpoints was assessed. The correlations among CCDC71L expression, mutational landscape and genome heterogeneity [mutant-allele tumor heterogeneity (MATH) and tumor purity] were detected by the data in TCGA.

RESULTS

CCDC71L expression was significantly upregulated in HNSCC, and positively associated with age, gender and N stage. Higher CCDC71L expression resulted in poor OS, RFS, DSS and PFI. Multivariate Cox regression analysis showed CCDC71L would be an independent prognostic marker in patients with HNSCC. Moreover, CCDC71L and the level of macrophage and neutrophil cells infiltration were significantly correlated in HNSCC. High expression of CCDC71L was related to immune checkpoint genes, oncogene mutations and genome heterogeneity markers.

CONCLUSION

These results implied that CCDC71L plays vital roles in HNSCC progression, which could be used as a underlying biomarker for the diagnosis and prognosis of HNSCC. Meanwhile, CCDC71L participates in immune regulation, which has a potential value for the immunotherapy of HNSCC patients.

Dysregulation of Fatty Acid Metabolism in Breast Cancer and Its Targeted Therapy

Breast cancer has become the number one cancer worldwide, there are challenges in its prevention, diagnosis and treatment, especially the pathogenesis of triple negative breast cancer has not been clear and the treatment dilemma of metastatic breast cancer. Metabolic reprogramming is currently considered to be one of the hallmarks of cancer, and metabolic alterations in breast cancer, including enhanced glycolysis, tricarboxylic acid cycle activity, glutamine catabolism, and fatty acid biosynthesis, are manifested differently in different breast cancer subtypes and have a complex relationship with tumor growth, metastasis, death, and drug resistance. At present, inhibitors of fatty acid synthesis and oxidation related enzymes have a certain effect in the treatment of breast cancer. In this paper, we review the studies on fatty acid metabolism in breast cancer to better understand the mechanism of fatty acid metabolism in breast cancer pathogenesis and hope to provide new ideas for targeting fatty acid metabolism in the treatment of breast cancer.

Progress in Lactate Metabolism and Its Regulation via Small Molecule Drugs

Lactate, once viewed as a byproduct of glycolysis and a metabolic "waste", is now recognized as an energy-providing substrate and a signaling molecule that modulates cellular functions under pathological conditions. The discovery of histone lactylation in 2019 marked a paradigm shift, with subsequent studies revealing that lactate can undergo lactylation with both histone and non-histone proteins, implicating it in the pathogenesis of various diseases, including cancer, liver fibrosis, sepsis, ischemic stroke, and acute kidney injury. Aberrant lactate metabolism is associated with disease onset, and its levels can predict disease outcomes. Targeting lactate production, transport, and lactylation may offer therapeutic potential for multiple diseases, yet a systematic summary of the small molecules modulating lactate and its metabolism in various diseases is lacking. This review outlines the sources and clearance of lactate, as well as its roles in cancer, liver fibrosis, sepsis, ischemic stroke, myocardial infarction, and acute kidney injury, and summarizes the effects of small molecules on lactate regulation. It aims to provide a reference and direction for future research.

Reprogramming SREBP1-dependent lipogenesis and inflammation in high-risk breast with licochalcone A: a novel path to cancer prevention

Background

Anti-estrogens have had limited impact on breast cancer (BC) prevention. Novel agents with better tolerability, and efficacy beyond estrogen receptor (ER) positive BC are needed. We studied licochalcone A (LicA) for ER-agnostic BC prevention.

Methods

We evaluated antiproliferative effects of LicA in seven breast cell lines and its suppression of ER+ and ER- xenograft tumors in mice. High-risk human breast tissue was treated with LicA ex vivo , followed by RNA sequencing and metabolism flux modeling. Confirmatory testing was performed in an independent specimen set and ER+/- BC cell lines using NanoString metabolic panel, proteomics, western blots, and spatiotemporally resolved cholesterol quantification in single cells.

Results

LicA suppressed proliferation in vitro and xenograft tumor growth in vivo . It downregulated pivotal steps in PI3K-AKT-SREBP1-dependent lipogenesis, suppressed PI3K and AKT phosphorylation, SREBP1 protein expression, and cholesterol levels in the plasma membrane inner leaflet, to the levels in normal breast cells. LicA also suppressed prostaglandin E2 synthesis and PRPS1-catalyzed de novo nucleotide biosynthesis, stalling proliferation; further evident by reduced MKI67 and BCL2 proteins.

Conclusions

LicA targets SREBP1, a central regulator of lipogenesis and immune response, reducing pro-tumorigenic aberrations in lipid homeostasis and inflammation. It is a promising non-endocrine candidate for BC prevention.

Glioma-Derived Exosomes and Their Application as Drug Nanoparticles

Glioblastoma Multiforme (GBM) is the most aggressive primary tumor of the Central Nervous System (CNS) with a low survival rate. The malignancy of GBM is sustained by a bidirectional crosstalk between tumor cells and the Tumor Microenvironment (TME). This mechanism of intercellular communication is mediated, at least in part, by the release of exosomes. Glioma-Derived Exosomes (GDEs) work, indeed, as potent signaling particles promoting the progression of brain tumors by inducing tumor proliferation, invasion, migration, angiogenesis and resistance to chemotherapy or radiation. Given their nanoscale size, exosomes can cross the blood-brain barrier (BBB), thus becoming not only a promising biomarker to predict diagnosis and prognosis but also a therapeutic target to treat GBM. In this review, we describe the structural and functional characteristics of exosomes and their involvement in GBM development, diagnosis, prognosis and treatment. In addition, we discuss how exosomes can be modified to be used as a therapeutic target/drug delivery system for clinical applications.

Label-Free Prediction of Tumor Metastatic Potential via Ramanome

Assessing metastatic potential is crucial for cancer treatment strategies. However, current methods are time-consuming, labor-intensive, and have limited sample accessibility. Therefore, this study aims to investigate the urgent need for rapid and accurate approaches by proposing a Ramanome-based metastasis index (RMI) using machine learning of single-cell Raman spectra to rapidly and accurately assess tumor cell metastatic potential. Validation with various cultured tumor cells and a mouse orthotopic model of pancreatic ductal adenocarcinoma show a Kendall rank correlation coefficient of 1 compared to Transwell experiments and histopathological assessments. Significantly, lipid-related Raman peaks are most influential in determining RMI. The lipidomic analysis confirmed strong correlations between metastatic potential and phosphatidylcholine, phosphatidylethanolamine, cholesteryl ester, ceramide, and bis(monoacylglycero)phosphate, crucial in cell membrane composition or signal transduction. Therefore, RMI is a valuable tool for predicting tumor metastatic potential and providing insights into metastasis mechanisms.

Roles of posttranslational modifications in lipid metabolism and cancer progression

Lipid metabolism reprogramming has emerged as a hallmark of malignant tumors. Lipids represent a complex group of biomolecules that not only compose the essential components of biological membranes and act as an energy source, but also function as messengers to integrate various signaling pathways. In tumor cells, de novo lipogenesis plays a crucial role in acquiring lipids to meet the demands of rapid growth. Increasing evidence has suggested that dysregulated lipid metabolism serves as a driver of cancer progression. Posttranslational modifications (PTMs), which occurs in most eukaryotic proteins throughout their lifetimes, affect the activity, abundance, function, localization, and interactions of target proteins. PTMs of crucial molecules are potential intervention sites and are emerging as promising strategies for the cancer treatment. However, there is limited information available regarding the PTMs that occur in cancer lipid metabolism and the potential treatment strategies associated with these PTMs. Herein, we summarize current knowledge of the roles and regulatory mechanisms of PTMs in lipid metabolism. Understanding the roles of PTMs in lipid metabolism in cancer could provide valuable insights into tumorigenesis and progression. Moreover, targeting PTMs in cancer lipid metabolism might represent a promising novel therapeutic strategy.

The acyltransferase transmembrane protein 68 regulates breast cancer cell proliferation by modulating triacylglycerol metabolism

BACKGROUND

Cellular carcinogenesis is often marked by the accumulation of lipid droplets (LDs) due to reprogrammed lipid metabolism. LDs are dynamic organelles that primarily store intracellular triacylglycerol (TAG) and cholesteryl esters (CEs). Transmembrane protein 68 (TMEM68), a potential modifier of human breast cancer risk and outcomes, functions as a diacylglycerol acyltransferase, synthesizing TAG. However, the specific roles of TMEM68 in breast cancer cells remain unclear.

METHODS

Gene expression profiling interactive analysis and survival analysis were conducted. TMEM68 was overexpressed or knockdown in breast cancer cells to assess its impact on cell proliferation, migration and invasion. Targeted quantitative lipidomic analysis and quantitative polymerase chain reaction were used to profile lipid alterations and examine gene expression related to lipid metabolism following changes in TMEM68 levels.

RESULTS

TMEM68 gene was upregulated in breast cancer patients and higher TMEM68 levels were associated with poorer survival outcomes. Overexpression of TMEM68 increased breast cancer cell proliferation and invasion, whereas knockdown had minimal or no impact on reducing proliferation and invasion. Altering TMEM68 levels resulted in corresponding changes in TAG levels and cytoplasmic LDs, with overexpression increasing both and knockdown decreasing them. Lipidomic analysis revealed that TMEM68 regulated TAG levels and altered diacylglycerol content in breast cancer cells. Additionally, TMEM68 influenced the metabolism of glycerophospholipids, CEs and acylcarnitines. TMEM68 also modified the expression of key genes encoding enzymes related to neutral lipid metabolism, including TAG and CEs.

CONCLUSIONS

TMEM68 is highly expressed in breast cancer and negatively correlated with survival. Its overexpression promotes breast cancer cell proliferation while knockdown has varied effects depending on TMEM68 levels. TMEM68 regulates intracellular TAG and LDs contents along with alterations in glycerophospholipids. These findings suggest that TMEM68 may drive breast cancer cells proliferation by modulating TAG and LD content.

tRNA-derived RNA fragment, tRF-18-8R6546D2, promotes pancreatic adenocarcinoma progression by directly targeting ASCL2

Pancreatic adenocarcinoma (PAAD) is a life-threatening cancer. Exploring new diagnosis and treatment targets helps improve its prognosis. tRNA-derived small non-coding RNAs (tsRNAs) are a novel type of gene expression regulators and their dysregulation is closely related to many human cancers. Yet the expression and functions of tsRNAs in PAAD are not well understood. Our study used RNA sequencing to identify tsRNA expression profiles in PAAD cells cultured in no or high glucose media and found tRF-18-8R6546D2 was an uncharacterized tsRNA, which has significantly high expression in PAAD cells and tissues. Clinically, tRF-18-8R6546D2 is linked to poor prognosis in PAAD patients and can be used to distinguish them from healthy populations. Functionally, in vitro and vivo, tRF-18-8R6546D2 over-expression promoted PAAD cell proliferation, migration and invasion, inhibited apoptosis, whereas tRF-18-8R6546D2 knock-down showed opposite effects. Mechanistically, tRF-18-8R6546D2 promoted PAAD malignancy partly by directly silencing ASCL2 and further regulating its downstream genes such as MYC and CASP3. These findings show that tRF-18-8R6546D2 is a novel oncogenic factor and can be a promising diagnostic or prognostic biomarker and therapeutic target for PAAD.

Cholesterol metabolism in pancreatic cancer and associated therapeutic strategies

Pancreatic cancer remains one of the most lethal cancers due to late diagnosis and high chemoresistance. Despite recent progression in the development of chemotherapies, immunotherapies, and potential nanoparticles-based approaches, the success rate of therapeutic response is limited which is further compounded by cancer drug resistance. Understanding of emerging biological and molecular pathways causative of pancreatic cancer's aggressive and chemoresistance is vital to improve the effectiveness of existing therapeutics and to develop new therapies. One such under-investigated and relatively less explored area of research is documenting the effect that lipids, specifically cholesterol, and its metabolism, impose on pancreatic cancer. Dysregulated cholesterol metabolism has a profound role in supporting cellular proliferation, survival, and promoting chemoresistance and this has been well established in various other cancers. Thus, we aimed to provide an in-depth review focusing on the significance of cholesterol metabolism in pancreatic cancer and relevant genes at play, molecular processes contributing to cellular cholesterol homeostasis, and current research efforts to develop new cholesterol-targeting therapeutics. We highlight the caveats, weigh in different experimental therapeutic strategies, and provide possible suggestions for future research highlighting cholesterol's importance as a therapeutic target against pancreatic cancer resistance and cancer progression.

LncRNA mediated metabolic reprogramming: the chief culprits of solid tumor malignant progression: an update review

Metabolism reprogramming (MR) is one of the top ten hallmarks of malignant tumors. The aberrant activation of MR has been recognized as a critical contributory factor to the malignant progression of solid tumors. Moreover, various long non-coding RNAs (lncRNAs) are implicated in the aberrant activation of MR in solid tumor cells. Therefore, in this review, we mainly focus on summarizing the functional relevance and molecular mechanistic underpinnings of lncRNAs in modulating MR of solid tumors by targeting glucose metabolism, lipid metabolism, affecting mitochondrial function, and regulating interactions between tumor and non-tumor cells in tumor microenvironment. Besides, we also underscore the potential for constructing lncRNAs-centered tumor metabolic regulation networks and developing novel anti-tumor strategies by targeting lncRNAs and abnormal MR. Ultimately, this review seeks to offer new targets and avenues for the clinical treatment of solid tumors in the future.

Research progress on anti-tumor mechanisms of scutellarin

Scutellarin, one of natural flavonoids from Scutellaria barbata D. Don and Erigeron breviscapus (vant) Hand.-Mazz. Modern pharmacological studies have shown that scutellarin has a good anti-tumor effect. According to the literature review at home and abroad, scutellarin can inhibit the growth and metastasis of tumor cells, block the cell cycle at various stages, induce apoptosis and autophagy, interfere with tumor metabolism, reverse drug resistance of tumor cells and enhance the sensitivity of chemotherapy drugs. In this paper, the anti-tumor mechanism of scutellarin was reviewed, and the shortcomings of current studies and future research directions were analyzed, so as to provide a basis for further exploration of the anti-tumor potential of scutellarin and its further development and utilization.

Treatment with trimetazidine dihydrochloride and lung cancer survival: Implications on metabolic re-programming

BACKGROUND

Metabolic re-wiring with preferential fatty acid oxidation has been observed in lung cancer cells. Whether the use of trimetazidine, an anti-anginal agent that inhibits fatty acid oxidation, alters clinical outcomes in ischemic heart disease (IHD) patients with lung cancers is unknown.

METHODS

We carried out this territory-wide, retrospective cohort study of 279,894 IHD patients prescribed with trimetazidine or long-acting oral nitrates in Hong Kong (population coverage of 7.5 millions, January 1999 - December 2020). A total of 6561 patients with pre-existing or de novo lung cancers were identified. Clinical outcomes of all-cause mortality were longitudinally compared between lung cancer patients who received trimetazidine (n = 547) versus non-users (control, n = 6014).

RESULTS

Over 902.9 ± 1410.6 days, lower incidence of deaths occurred in the trimetazidine group (79.0 %, n = 432/547) compared to controls (90.5 %, n = 5442/6014, P < 0.001). Kaplan-Meier analyses showed that trimetazidine use was associated with significantly higher survival from all-cause mortality in IHD patients (trimetazidine: mean survival = 1840.6 [95 %CI 1596.0-2085.3], versus control: 1056.7 [95 %CI 1011.3-1102.0] days, Log Rank = 69.4, P < 0.001). Cox regression showed that trimetazidine use was significantly associated with reduced risk of all-cause mortality in crude (HR = 0.60 [95 %CI: 0.53 to 0.68], P < 0.001) and multivariable models (HR = 0.65 [95 % CI: 0.57 to 0.74], P < 0.001). Pre-specified analyses amongst patients with pre-existing lung cancers yielded similar findings (HR = 0.49 [95 %CI: 0.35 to 0.67], P < 0.001). Survival benefits related to trimetazidine use was predominantly restricted to non-cardiovascular mortality (P < 0.001).

CONCLUSIONS

Trimetazidine use is associated with higher overall survival in IHD patients with lung cancers, particularly from non-cardiovascular death. These findings need to be confirmed by randomized controlled trials.

A patent review of lactate dehydrogenase inhibitors (2014-present)

INTRODUCTION

Lactate dehydrogenase (LDH) is a key enzyme in glycolysis responsible for the conversion of pyruvate into lactate and vice versa. Lactate plays a crucial role in tumor progression and metastasis; therefore, reducing lactate production by inhibiting LDH is considered an optimal strategy to tackle cancer. Additionally, dysregulation of LDH activity is correlated with other pathologies, such as cardiovascular and neurodegenerative diseases as well as primary hyperoxaluria, fibrosis and cryptosporidiosis. Hence, LDH inhibitors could serve as potential therapeutics for treating these pathological conditions.

AREAS COVERED

This review covers patents published since 2014 up to the present in the Espacenet database, concerning LDH inhibitors and their potential therapeutic applications.

EXPERT OPINION

Over the past 10 years, different compounds have been identified as LDH inhibitors. Some of them are derived from the chemical optimization of already known LDH inhibitors (e.g. pyrazolyl derivatives, quinoline 3-sulfonamides), while others belong to newly identified chemical classes of LDH inhibitors. LDH inhibition has proven to be a promising therapeutic strategy not only for preventing human pathologies, but also for treating animal diseases. The published patents from both academia and the pharmaceutical industry highlight the persistent high interest of the scientific community in developing efficient LDH inhibitors.

Fighting ischemia-reperfusion injury: Focusing on mitochondria-derived ferroptosis

Ischemia-reperfusion injury (IRI) is a major cause of mortality and morbidity. Current treatments for IRI have limited efficacy and novel therapeutic strategies are needed. Mitochondrial dysfunction not only initiates IRI but also plays a significant role in ferroptosis pathogenesis. Recent studies have highlighted that targeting mitochondrial pathways is a promising therapeutic approach for ferroptosis-induced IRI. The association between ferroptosis and IRI has been reviewed many times, but our review provides the first comprehensive overview with a focus on recent mitochondrial research. First, we present the role of mitochondria in ferroptosis. Then, we summarize the evidence on mitochondrial manipulation of ferroptosis in IRI and review recent therapeutic strategies aimed at targeting mitochondria-related ferroptosis to mitigate IRI. We hope our review will provide new ideas for the treatment of IRI and accelerate the transition from bench to bedside.

Precise targeting of lipid metabolism in the era of immuno-oncology and the latest advances in nano-based drug delivery systems for cancer therapy

Over the past decade, research has increasingly identified unique dysregulations in lipid metabolism within the tumor microenvironment (TME). Lipids, diverse biomolecules, not only constitute biological membranes but also function as signaling molecules and energy sources. Enhanced synthesis or uptake of lipids in the TME significantly promotes tumorigenesis and proliferation. Moreover, lipids secreted into the TME influence tumor-resident immune cells (TRICs), thereby aiding tumor survival against chemotherapy and immunotherapy. This review aims to highlight recent advancements in understanding lipid metabolism in both tumor cells and TRICs, with a particular emphasis on exogenous lipid uptake and endogenous lipid de novo synthesis. Targeting lipid metabolism for intervention in anticancer therapies offers a promising therapeutic avenue for cancer treatment. Nano-drug delivery systems (NDDSs) have emerged as a means to maximize anti-tumor effects by rewiring tumor metabolism. This review provides a comprehensive overview of recent literature on the development of NDDSs targeting tumor lipid metabolism, particularly in the context of tumor immunotherapy. It covers four key aspects: reprogramming lipid uptake, reprogramming lipolysis, reshaping fatty acid oxidation (FAO), and reshuffling lipid composition on the cell membrane. The review concludes with a discussion of future prospects and challenges in this burgeoning field of research.

Transgelin 2 guards T cell lipid metabolism and antitumour function

Mounting effective immunity against pathogens and tumours relies on the successful metabolic programming of T cells by extracellular fatty acids1-3. Fatty-acid-binding protein 5 (FABP5) has a key role in this process by coordinating the efficient import and trafficking of lipids that fuel mitochondrial respiration to sustain the bioenergetic requirements of protective CD8+ T cells4,5. However, the mechanisms that govern this immunometabolic axis remain unexplored. Here we report that the cytoskeletal organizer transgelin 2 (TAGLN2) is necessary for optimal fatty acid uptake, mitochondrial respiration and anticancer function in CD8+ T cells. TAGLN2 interacts with FABP5 to facilitate its cell surface localization and function in activated CD8+ T cells. Analyses of ovarian cancer specimens revealed that endoplasmic reticulum (ER) stress responses induced by the tumour microenvironment repress TAGLN2 in infiltrating CD8+ T cells, thereby enforcing their dysfunctional state. Restoring TAGLN2 expression in ER-stressed CD8+ T cells increased their lipid uptake, mitochondrial respiration and cytotoxic capacity. Accordingly, chimeric antigen receptor T cells overexpressing TAGLN2 bypassed the detrimental effects of tumour-induced ER stress and demonstrated therapeutic efficacy in mice with metastatic ovarian cancer. Our study establishes the role of cytoskeletal TAGLN2 in T cell lipid metabolism and highlights the potential to enhance cellular immunotherapy in solid malignancies by preserving the TAGLN2-FABP5 axis.

Clitoria ternatea L. flower-derived anthocyanins and flavonoids inhibit bladder cancer growth by suppressing SREBP1 pathway-mediated fatty acid synthesis

Clitoria ternatea L. flowers are used as traditional herbal medicines and are known for their advanced pharmacological activities. Flavonoids and anthocyanins reportedly contribute to the therapeutic properties of C. ternatea flowers; however, their potential anti-bladder cancer effects and molecular mechanisms remain unknown. In this study, flavonoid- and anthocyanin-rich samples from C. ternatea flowers (DDH) are prepared via macroporous resin-based extraction coupled with an efficient and reliable two-dimensional UPLC-DAD-MS/MS method. In vitro and in vivo studies reveal that DDH can inhibit bladder cancer cell growth and enhance the anti-bladder cancer activity of cisplatin. RNA-seq combined with KEGG analysis reveals that fatty acid synthesis is closely related to the anti-bladder cancer effect of DDH. Furthermore, DDH dose-dependently reduces cellular fatty acid levels in bladder cancer cells, and the addition of fatty acids significantly mitigates DDH-induced cell growth inhibition. Subsequent findings reveal that DDH downregulates sterol regulatory element-binding protein 1 (SREBP1), a key transcriptional regulator of de novo fatty acid synthesis in cancer cells, and its downstream targets (FASN, SCD1, and ACC). Additionally, this study demonstrates that gallic acid not only enhances the stability of DDH but also synergistically potentiates its anti-bladder cancer activity. Our study suggests that targeting the SREBP1 pathway is an effective strategy in bladder cancer therapy, and the ability of DDH to induce cell death by inhibiting the SREBP1 pathway and its good tolerance in mice make it a promising strategy for preventing and treating bladder cancer.

Construction of machine learning models of lipid metabolism-related long non-coding RNA in lung adenocarcinoma is associated with microenvironmental heterogeneity and immunotherapy

Using various bioinformatics tools, we constructed a prognostic model integrating the expression profiles of lipid metabolization-related lncRNAs and clinical features. Our study discovered that various lipid metabolism-related lncRNAs were linked to the prognosis of lung adenocarcinoma. The link between immune cell infiltration in the tumour microenvironment and the expression level of lncRNAs involved with lipid metabolism was also investigated. Our findings suggest that there is a complex interplay between lipid metabolism, microenvironmental heterogeneity, and immunotherapy in lung adenocarcinoma. Furthermore, the study has significant clinical implications for the development of effective therapies for patients with lung adenocarcinoma by investigating the potential of these lncRNAs as biomarkers for anticipating the response to immunotherapy. Finally, our study emphasises the significance of continued analysis of lncRNAs associated with lipid metabolism in tumours to better understand the mechanisms behind the incidence and progression of lung adenocarcinoma. Several of the strengths of our work are the extensive analysis of the relationship between lipid metabolism and lncRNAs in lung adenocarcinoma and the utilization of a sizable sample size from the TCGA-LUAD cohort. However, there are also some limitations. Firstly, the mechanisms of how these lncRNAs interact with lipid metabolism pathways and immune response require further investigation. Secondly, our study was based on bioinformatics analysis and lacked experimental verification. Finally, our study was limited to the TCGA-LUAD cohort and further validation using other independent cohorts is required. In conclusion, our study provides a comprehensive and systematic analysis of lncRNAs associated with lipid metabolism in lung adenocarcinoma. Lung cancer patients may benefit from using identified lncRNAs as therapeutic targets and prognostic biomarkers. Validating these findings and confirming the potential therapeutic applications of these lncRNAs will require more mechanistic research.

Integration of transcriptomics and machine learning for insights into breast cancer: exploring lipid metabolism and immune interactions

Background

Breast cancer (BRCA) represents a substantial global health challenge marked by inadequate early detection rates. The complex interplay between the tumor immune microenvironment and fatty acid metabolism in BRCA requires further investigation to elucidate the specific role of lipid metabolism in this disease.

Methods

We systematically integrated nine machine learning algorithms into 184 unique combinations to develop a consensus model for lipid metabolism-related prognostic genes (LMPGS). Additionally, transcriptomics analysis provided a comprehensive understanding of this prognostic signature. Using the ESTIMATE method, we evaluated immune infiltration among different risk subgroups and assessed their responsiveness to immunotherapy. Tailored treatments were screened for specific risk subgroups. Finally, we verified the expression of key genes through in vitro experiments.

Results

We identified 259 differentially expressed genes (DEGs) related to lipid metabolism through analysis of the cancer genome atlas program (TCGA) database. Subsequently, via univariate Cox regression analysis and C-index analysis, we developed an optimal machine learning algorithm to construct a 21-gene LMPGS model. We used optimal cutoff values to divide the lipid metabolism prognostic gene scores into two groups according to high and low scores. Our study revealed distinct biological functions and mutation landscapes between high-scoring and low-scoring patients. The low-scoring group presented a greater immune score, whereas the high-scoring group presented enhanced responses to both immunotherapy and chemotherapy drugs. Single-cell analysis highlighted significant upregulation of CPNE3 in epithelial cells. Moreover, by employing molecular docking, we identified niclosamide as a potential targeted therapeutic drug. Finally, our experiments demonstrated high expression of MTMR9 and CPNE3 in BRCA and their significant correlation with prognosis.

Conclusion

By employing bioinformatics and diverse machine learning algorithms, we successfully identified genes associated with lipid metabolism in BRCA and uncovered potential therapeutic agents, thereby offering novel insights into the mechanisms and treatment strategies for BRCA.

Combined spatially resolved metabolomics and spatial transcriptomics reveal the mechanism of RACK1-mediated fatty acid synthesis

Lipid metabolism is altered in rapidly proliferating cancer cells, where fatty acids (FAs) are utilized in the synthesis of sphingolipids and glycerophospholipids to produce cell membranes and signaling molecules. Receptor for activated C-kinase 1 (RACK1; also known as small ribosomal subunit protein) is an intracellular scaffolding protein involved in signaling pathways. Whether such lipid metabolism is regulated by RACK1 is unknown. Here, integrated spatially resolved metabolomics and spatial transcriptomics revealed that accumulation of lipids in cervical cancer (CC) samples correlated with overexpression of RACK1, and RACK1 promoted lipid synthesis in CC cells. Chromatin immunoprecipitation verified binding of sterol regulatory element-binding protein 1 (SREBP1) to acetyl-CoA carboxylase (ACC) and fatty acid synthase (FASN) promoters. RACK1 enhanced de novo FA synthesis by upregulating expression of sterol regulatory element binding transcription factor 1 (SREBP1) and lipogenic genes FASN and ACC1. Co-immunoprecipitation and western blotting revealed that RACK1 interacted with protein kinase B (AKT) to activate the AKT/mammalian target of rapamycin (mTOR)/SREBP1 signaling pathway to promote FA synthesis. Cell proliferation and apoptosis experiments suggested that RACK1-regulated FA synthesis is key in the progression of CC. Thus, RACK1 enhanced lipid synthesis through the AKT/mTOR/SREBP1 signaling pathway to promote the growth of CC cells. RACK1 may become a therapeutic target for CC.

Associations between pre-operative cholesterol levels with long-term survival after colorectal cancer surgery: a nationwide propensity score-matched cohort study

PURPOSE

Altered lipid metabolism frequently occurs in patients with solid cancers and dyslipidemia has been associated with poorer outcomes in patients with colorectal cancer. This study sought to investigate whether cholesterol levels are associated with clinical outcomes and can serve as survival predictors.

METHODS

We conducted a retrospective cohort study with Danish patients diagnosed with colorectal cancer who had surgery with curative intent for UICC stages I to III between 2015 and 2020. Using propensity score adjustment, we matched patients in a 1:1 ratio to examine the impact of total cholesterol (TC) > 4 mmol/L vs. ≤ 4 mmol/L within 365 days prior to surgery on overall survival (OS) and disease-free survival (DFS).

RESULTS

A total of 3443 patients were included in the study. Median follow-up time was 3.8 years. Following propensity score matching, 1572 patients were included in the main analysis. There was no statistically significant difference in OS or DFS between patients with TC > 4 mmol/L compared with TC ≤ 4 mmol/L (HR: 0.82, 95% CI, 0.65-1.03, HR: 0.87, 95% CI, 0.68-1.12, respectively.). A subgroup analysis investigating TC > 4 mmol/L as well as low-density lipoprotein (LDL) > 3 mmol/L found a significant correlation with OS (HR: 0.74, 95% CI, 0.54-0.99).

CONCLUSION

TC levels alone were not associated with OS or DFS in patients with colorectal cancer. Interestingly, higher TC and LDL levels were linked to better overall survival, suggesting the need for further exploration of cholesterol's role in colorectal cancer.

TRIAL REGISTRATION

Not applicable.

Fast and broad-coverage lipidomics enabled by ion mobility-mass spectrometry

Aberrant lipid metabolism has been widely recognized as a hallmark of various diseases. However, the comprehensive analysis of distinct lipids is challenging due to the complexity of lipid molecular structures, wide concentration ranges, and numerous isobaric and isomeric lipids. Usually, liquid chromatography-mass spectrometry (LC-MS)-based lipidomics requires a long time for chromatographic separation to achieve optimal separation and selectivity. Ion mobility (IM) adds a new separation dimension to LC-MS, significantly enhancing the coverage, sensitivity, and resolving power. We took advantage of the rapid separation provided by ion mobility and optimized a fast and broad-coverage lipidomics method using the LC-IM-MS technology. The method required only 8 minutes for separation and detected over 1000 lipid molecules in a single analysis of common biological samples. The high reproducibility and accurate quantification of this high-throughput lipidomics method were systematically characterized. We then applied the method to comprehensively measure dysregulated lipid metabolism in patients with colorectal cancer (CRC). Our results revealed 115 significantly changed lipid species between preoperative and postoperative plasma of patients with CRC and also disclosed associated differences in lipid classes such as phosphatidylcholines (PC), sphingomyelins (SM), and triglycerides (TG) regarding carbon number and double bond. Together, a fast and broad-coverage lipidomics method was developed using ion mobility-mass spectrometry. This method is feasible for large-scale clinical lipidomic studies, as it effectively balances the requirements of high-throughput and broad-coverage in clinical studies.

De novo lipid synthesis and polarized prenylation drive cell invasion through basement membrane

To breach the basement membrane, cells in development and cancer use large, transient, specialized lipid-rich membrane protrusions. Using live imaging, endogenous protein tagging, and cell-specific RNAi during Caenorhabditis elegans anchor cell (AC) invasion, we demonstrate that the lipogenic SREBP transcription factor SBP-1 drives the expression of the fatty acid synthesis enzymes POD-2 and FASN-1 prior to invasion. We show that phospholipid-producing LPIN-1 and sphingomyelin synthase SMS-1, which use fatty acids as substrates, produce lysosome stores that build the AC's invasive protrusion, and that SMS-1 also promotes protrusion localization of the lipid raft partitioning ZMP-1 matrix metalloproteinase. Finally, we discover that HMG-CoA reductase HMGR-1, which generates isoprenoids for prenylation, localizes to the ER and enriches in peroxisomes at the AC invasive front, and that the final transmembrane prenylation enzyme, ICMT-1, localizes to endoplasmic reticulum exit sites that dynamically polarize to deliver prenylated GTPases for protrusion formation. Together, these results reveal a collaboration between lipogenesis and a polarized lipid prenylation system that drives invasive protrusion formation.

Growth Signaling Networks Orchestrate Cancer Metabolic Networks

Normal cells grow and divide only when instructed to by signaling pathways stimulated by exogenous growth factors. A nearly ubiquitous feature of cancer cells is their capacity to grow independent of such signals, in an uncontrolled, cell-intrinsic manner. This property arises due to the frequent oncogenic activation of core growth factor signaling pathway components, including receptor tyrosine kinases, PI3K-AKT, RAS-RAF, mTORC1, and MYC, leading to the aberrant propagation of pro-growth signals independent of exogenous growth factors. The growth of both normal and cancer cells requires the acquisition of nutrients and their anabolic conversion to the primary macromolecules underlying biomass production (protein, nucleic acids, and lipids). The core growth factor signaling pathways exert tight regulation of these metabolic processes and the oncogenic activation of these pathways drive the key metabolic properties of cancer cells and tumors. Here, we review the molecular mechanisms through which these growth signaling pathways control and coordinate cancer metabolism.

Application of galactosylated albumin for targeted delivery of triptolide to suppress hepatocellular carcinoma progression through inhibiting de novo lipogenesis

Hepatocellular carcinoma (HCC) remains the fourth leading cause of cancer-associated death globally with a lack of efficient therapy. The pathogenesis of HCC is a complex and multistep process, highly reliant on de novo lipogenesis, from which tumor cells can incorporate fatty acids to satisfy the necessary energy demands of rapid proliferation and provide survival advantages. Triptolide (TP) is a bioactive ingredient exhibiting potent abilities of anti-proliferation and lipid metabolism regulation, but its clinical application is constrained because of its toxicity and non-specific distribution. The present study has developed galactosylated bovine serum albumin nanoparticles loaded with TP (Gal-BSA-TP NPs) to alleviate systemic toxicity and increase tumor-targeting and antitumor efficacy. Furthermore, Gal-BSA-TP NPs could inhibit de novo lipogenesis via the p53-SREBP1C-FASN pathway to deprive the fuel supply of HCC, offering a specific strategy for HCC treatment. In general, this study provided a biocompatible delivery platform for targeted therapy for HCC from the perspective of de novo lipogenesis.

Regulation of cancer cell lipid metabolism and oxidative phosphorylation by microenvironmental acidosis

The expansion of cancer cell mass in solid tumors generates a harsh environment characterized by dynamically varying levels of acidosis, hypoxia, and nutrient deprivation. Because acidosis inhibits glycolytic metabolism and hypoxia inhibits oxidative phosphorylation, cancer cells that survive and grow in these environments must rewire their metabolism and develop a high degree of metabolic plasticity to meet their energetic and biosynthetic demands. Cancer cells frequently upregulate pathways enabling the uptake and utilization of lipids and other nutrients derived from dead or recruited stromal cells, and in particular lipid uptake is strongly enhanced in acidic microenvironments. The resulting lipid accumulation and increased reliance on β-oxidation and mitochondrial metabolism increase susceptibility to oxidative stress, lipotoxicity, and ferroptosis, in turn driving changes that may mitigate such risks. The spatially and temporally heterogeneous tumor microenvironment thus selects for invasive, metabolically flexible, and resilient cancer cells capable of exploiting their local conditions and of seeking out more favorable surroundings. This phenotype relies on the interplay between metabolism, acidosis, and oncogenic mutations, driving metabolic signaling pathways such as peroxisome proliferator-activated receptors (PPARs). Understanding the particular vulnerabilities of such cells may uncover novel therapeutic liabilities of the most aggressive cancer cells.

NUP37 accumulation mediated by TRIM28 enhances lipid synthesis to accelerate HCC progression

Elevated intracellular lipid synthesis is important for hepatocellular carcinoma (HCC) progression. Our study aimed to identify the role of nucleoporin 37 (NUP37) in lipid synthesis and HCC progression. The expression of NUP37 was significantly upregulated in HCC and associated with a poor prognosis. NUP37 silencing suppressed lipid synthesis, proliferation, migration, and invasion of HCC cells in vitro, and restrained tumor growth in xenograft mouse models in vivo. Next, we found the high expression of NUP37 in HCC was related to post-translational modifications. Tripartite motif-containing 28 (TRIM28) was identified as an interacting protein of NUP37 and upregulated its protein level. The subsequent analysis revealed that TRIM28-mediated SUMOylation of NUP37 at Lys114/118/246 inhibited K27-linked polyubiquitination of NUP37, which is one reason for its high expression level in HCC. In conclusion, TRIM28 SUMOylates NUP37 to prevent its ubiquitination and proteasomal degradation, increasing the stability of the NUP37 protein, thereby promoting lipid synthesis and the progression of HCC.

Long noncoding RNA UCA1 inhibits epirubicin-induced apoptosis by activating PPARα-mediated lipid metabolism

Metabolic reprogramming is a hallmark of cancer, and abnormal lipid metabolism is associated with drug resistance in bladder cancer cells. The long noncoding RNA (lncRNA) UCA1 is overexpressed in bladder cancer, but its functional contribution to lipid metabolism remains uncharacterized. In this study, we demonstrated that lncRNA UCA1 inhibits epirubicin-induced cell apoptosis by supporting abnormal lipid metabolism in bladder cancer cells. Mechanistically, lncRNA UCA1 promotes lipid accumulation in vitro and in vivo by upregulating PPARα mRNA and protein expression, which is mediated by miR-30a-3p. Knockdown of lncRNA UCA1 increased epirubicin-induced apoptosis via miR-30a-3p/PPARα and downstream p-AKT/p-GSK-3β/β-catenin signaling. Furthermore, mixed free fatty acids upregulated lncRNA UCA1 expression by promoting recruitment of the transcription factor RXRα to the lncRNA UCA1 promoter. These findings were verified in a mouse xenograft model and are consistent with the expression patterns in human bladder cancer patients. Overall, these findings establish the role of lncRNA UCA1 in lipid metabolism and bladder cancer cell resistance to epirubicin, suggesting that lncRNA UCA1 may serve as a candidate target for enhancing bladder cancer chemotherapy.

Metal complex lipid-based nanoparticles deliver metabolism-regulating lomitapide to overcome CTC immune evasion via activating STING pathway

Activating the cGAS-STING pathway of circulating tumor cell clusters (CTC clusters) represents a promising strategy to mitigate metastases. To fully exploit the potential of cholesterol-regulating agents in activating CTCs' STING levels, we developed a nanoparticle (NP) composed of metal complex lipid (MCL). This design includes MCL-miriplatin to increase NP stiffness and loads lomitapide (lomi) modulating cholesterol levels, resulting in the creation of PLTs@Pt-lipid@lomi NPs. MCL-miriplatin not only enhances lomi's eliciting efficacy on STING pathway but also increases NPs' stiffness, thus a vital factor affecting the penetration into CTC clusters to further boost lomi's ability. Demonstrated by cy5 tracking experiments, PLTs@Pt-lipid@lomi NPs quickly attach to cancer cell via platelet membrane anchorage, penetrate deep into the spheres, and reach the subcellular endoplasmic reticulum where lomi regulates cholesterol. Additionally, these NPs have been shown to track CTCs in the bloodstream, a capability not demonstrated by the free drug. PLTs@Pt-lipid@lomi NPs more efficiently activate the STING pathway and reduce CTC stemness compared to free lomi. Ultimately, PLTs@Pt-lipid@lomi NPs reduce metastasis in a post-surgery animal model. While cholesterol-regulating agents are limited in efficacy when being repositioned as immunomodulatory agents, this MCL-composing NP strategy demonstrates the potential to effectively deliver these agents to target CTC clusters.

ARHGEF39 targeted by E2F1 fosters hepatocellular carcinoma metastasis by mediating fatty acid metabolism

BACKGROUND

Hepatocellular carcinoma (HCC) stands as the prevailing manifestation of primary liver cancer. Previous studies have implicated ARHGEF39 in various cancer progression processes, but its impact on HCC metastasis remains unclear.

METHODS

Bioinformatics analysis and qRT-PCR were employed to test ARHGEF39 expression in HCC tissues and cells, identified enriched pathways associated with ARHGEF39, and investigated its regulatory relationship with E2F1. The impact of ARHGEF39 overexpression or knockdown on cellular phenotypes in HCC was assessed through the implementation of CCK-8 and Transwell assays. Accumulation of neutral lipids was determined by BODIPY 493/503 staining, while levels of triglycerides and phospholipids were measured using specific assay kits. Expression of E-cadherin, Vimentin, MMP-2, MMP-9, and FASN were analyzed by Western blot. The interaction between ARHGEF39 and E2F1 was validated through ChIP and dual-luciferase reporter assays.

RESULTS

Our study demonstrated upregulated expression of both ARHGEF39 and E2F1 in HCC, with ARHGEF39 being associated with fatty acid metabolism (FAM) pathways. Additionally, ARHGEF39 was identified as a downstream target gene of E2F1. Cell-based experiments unmasked that high expression of ARHGEF39 mediated the promotion of HCC cell viability, migration, and invasion via enhanced FAM. Moreover, rescue assays demonstrated that the promotion of HCC cell metastasis by high ARHGEF39 expression was attenuated upon treatment with Orlistat. Conversely, the knockdown of E2F1 suppressed HCC cell metastasis and FAM, while the upregulation of ARHGEF39 counteracted the repressive effects of E2F1 downregulation on the metastatic potential of HCC cells.

CONCLUSION

Our findings confirmed the critical role of ARHGEF39 in HCC metastasis and unmasked potential molecular mechanisms through which ARHGEF39 fostered HCC metastasis via FAM, providing a theoretical basis for exploring novel molecular markers and preventive strategies for HCC metastasis.