ELOVL5-mediated fatty acid elongation promotes cellular proliferation and invasion in renal cell carcinoma

Co-morbid intersections of cancer and cardiovascular disease and targets for natural drug action: Reprogramming of lipid metabolism

Cancer and cardiovascular diseases are major contributors to global morbidity and mortality, and their seemingly separate pathologies are intricately intertwined. In the context of cancer, the cardiovascular disease encompasses not only the side effects arising from anti-tumor treatments but also the metabolic shifts induced by oncological conditions. A growing body of research indicates that lipid metabolic reprogramming serves as a distinctive hallmark of tumors. Furthermore, anomalies in lipid metabolism play a significant role in the development of cardiovascular disease. This study delves into the cardiac implications of lipid metabolic reprogramming within the cancer context, closely examining abnormalities in lipid metabolism present in tumors, cardiac tissue, and immune cells within the microenvironment. Additionally, we examined risk factors such as obesity and anti-tumor therapy. Despite progress, a gap remains in the availability of drugs targeting lipid metabolism modulation for treating tumors and mitigating cardiac risk, with limited advancement seen in prior studies. Here, we present a review of previous research on natural drugs that exhibit both shared and distinct therapeutic effects on tumors and cardiac health by modulating lipid metabolism. Our aim is to provide insights for potential drug development.

Machine learning-based identification and immune characterization of ferroptosis-related molecular clusters in osteoarthritis and validation

Osteoarthritis (OA), a degenerative joint disease, involves synovial inflammation, subchondral bone erosion, and cartilage degeneration. Ferroptosis, a regulated non-apoptotic programmed cell death, is associated with various diseases. This study investigates ferroptosis-related molecular subtypes in OA to comprehend underlying mechanisms. The Gene Expression Omnibus datasets GSE206848, GSE55457, GSE55235, GSE77298 and GSE82107 were used utilized. Unsupervised clustering identified the ferroptosis-related gene (FRG) subtypes, and their immune characteristics were assessed. FRG signatures were derived using LASSO and SVM-RFE algorithms, forming models to evaluate OA's ferroptosis-related immune features. Three FRG clusters were found to be immunologically heterogeneous, with cluster 1 displaying robust immune response. Models identified nine key signature genes via algorithms, demonstrating strong diagnostic and prognostic performance. Finally, qRT-PCR and Western blot validated these genes, offering consistent results. In addition, some of these genes may have implications as new therapeutic targets and can be used to guide clinical applications.

Prediction of prognosis and immunotherapy efficacy based on metabolic landscape in lung adenocarcinoma by bulk, single-cell RNA sequencing and Mendelian randomization analyses

Immunotherapy has been a remarkable clinical advancement in cancer treatment, but only a few patients benefit from it. Metabolic reprogramming is tightly associated with immunotherapy efficacy and clinical outcomes. However, comprehensively analyzing their relationship is still lacking in lung adenocarcinoma (LUAD). Herein, we evaluated 84 metabolic pathways in TCGA-LUAD by ssGSEA. A matrix of metabolic pathway pairs was generated and a metabolic pathway-pair score (MPPS) model was established by univariable, LASSO, multivariable Cox regression analyses. The differences of metabolic reprogramming, tumor microenvironment (TME), tumor mutation burden and drug sensitivity in different MPPS groups were further explored. WGCNA and 117 machine learning algorithms were performed to identify MPPS-related genes. Single-cell RNA sequencing and in vitro experiments were used to explore the role of C1QTNF6 on TME. The results showed MPPS model accurately predicted prognosis and immunotherapy efficacy of LUAD patients regardless of sequencing platforms. High-MPPS group had worse prognosis, immunotherapy efficacy and lower immune cells infiltration, immune-related genes expression and cancer-immunity cycle scores than low-MPPS group. Seven MPPS-related genes were identified, of which C1QTNF6 was mainly expressed in fibroblasts. High C1QTNF6 expression in fibroblasts was associated with more infiltration of M2 macrophage, Treg cells and less infiltration of NK cells, memory CD8+ T cells. In vitro experiments validated silencing C1QTNF6 in fibroblasts could inhibit M2 macrophage polarization and migration. The study depicted the metabolic landscape of LUAD and constructed a MPPS model to accurately predict prognosis and immunotherapy efficacy. C1QTNF6 was a promising target to regulate M2 macrophage polarization and migration.

Label-free quantitative proteomics reveals the mechanisms of Aurora kinase B in renal cell carcinoma

Background

Renal cell carcinoma is the most common form of kidney cancer which is a global threat to human health, needing to explore effective therapeutic targets and treatment methods. Aurora kinase B acts as an important carcinogenic role in various kinds of tumors, while its mechanism in renal cell carcinoma is indistinct. Herein we explore the underlying mechanism of Aurora kinase B in renal cell carcinoma.

Methods and results

Label-free quantitative proteomics analysis was employed to analyze the differentially expressed proteins in 786-O cells which were treated with si-Aurora kinase B or si-ctrl. In the current study, 169 differentially expressed proteins were identified. The top 10 upregulated proteins were MX2, IFI44L, ISG20, DDX58, F3, IFI44, ECE1, PRIC285, NIT1, and IFIT2. The top 10 downregulated proteins were FKBP9, FSTL1, DDAH1, TGFB2, HMGN3, COIL, FAM65A, PTPN14, ARFGAP2, and EIF2C2. GO enrichment analysis showed that these differentially expressed proteins participated in biological processes, including defense response to virus, response to virus, and type I interferon signaling pathway. These differentially expressed proteins participated in cellular components, including focal adhesion, cell-substrate adherens junction, cell-substrate junction, and endoplasmic reticulum lumen. These differentially expressed proteins participated in molecule functions, including guanyl nucleotide binding, nucleotidase activity, double-stranded RNA binding, 2'-5'-oligoadenylate synthetase activity, and virus receptor activity. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that the significantly changed proteins including OAS3, OAS2, JAK1, TAP1, and RAC1 were involved in Epstein-Barr virus infection.

Conclusions

Taken together, our results demonstrate the possible mechanisms that Aurora kinase B may participate in renal cell carcinoma. These findings may provide insights into tumorigenesis and a theoretical basis for developing potential therapies of renal cell carcinoma.

The Effect of Silencing Fatty Acid Elongase 4 and 6 Genes on the Proliferation and Migration of Colorectal Cancer Cells

Colorectal cancer (CRC) cells show some alterations in lipid metabolism, including an increased fatty acid elongation. This study was focused on investigating the effect of a small interfering RNA (siRNA)-mediated decrease in fatty acid elongation on CRC cells' survival and migration. In our study, the elongase 4 (ELOVL4) and elongase 6 (ELOVL6) genes were observed to be highly overexpressed in both the CRC tissue obtained from patients and the CRC cells cultured in vitro (HT-29 and WiDr cell lines). The use of the siRNAs for ELOVL4 and ELOVL6 reduced cancer cell proliferation and migration rates. These findings indicate that the altered elongation process decreased the survival of CRC cells, and in the future, fatty acid elongases can be potentially good targets in novel CRC therapy.

A comprehensive review of the family of very-long-chain fatty acid elongases: structure, function, and implications in physiology and pathology

BACKGROUND

The very-long-chain fatty acid elongase (ELOVL) family plays essential roles in lipid metabolism and cellular functions. This comprehensive review explores the structural characteristics, functional properties, and physiological significance of individual ELOVL isoforms, providing insights into lipid biosynthesis, cell membrane dynamics, and signaling pathways.

AIM OF REVIEW

This review aims to highlight the significance of the ELOVL family in normal physiology and disease development. By synthesizing current knowledge, we underscore the relevance of ELOVLs as potential therapeutic targets.

KEY SCIENTIFIC CONCEPTS OF REVIEW

We emphasize the association between dysregulated ELOVL expression and diseases, including metabolic disorders, skin diseases, neurodegenerative conditions, and cancer. The intricate involvement of ELOVLs in cancer biology, from tumor initiation to metastasis, highlights their potential as targets for anticancer therapies. Additionally, we discuss the prospects of using isoform-specific inhibitors and activators for metabolic disorders and cancer treatment. The identification of ELOVL-based biomarkers may advance diagnostics and personalized medicine.

CONCLUSION

The ELOVL family's multifaceted roles in lipid metabolism and cellular physiology underscore its importance in health and disease. Understanding their functions offers potential therapeutic avenues and personalized treatments.

Comprehensive analysis of transcriptomic and metabolomic profiles uncovered the age-induced dynamic development pattern of subcutaneous fat in Ningxiang pig

Enhancing meat production and quality is the eternal theme for pig breeding industries. Fat deposition has always been the focus of research in practical production because it is closely linked to pig production efficiency and pork quality. In the current study, multi-omics techniques were performed to explore the modulatory mechanisms of backfat (BF) accumulation at three core developmental stages for Ningxiang pigs. Our results identified that 15 differentially expressed genes (DEGs) and 9 significantly changed metabolites (SCMs) contributed to the BF development via the cAMP signaling pathway, regulation of lipolysis in adipocytes, and biosynthesis of unsaturated fatty acids. Herein, we found a series of candidate genes such as adrenoceptor beta 1 (ADRB1), adenylate cyclase 5 (ADCY5), ATPase Na+/K+ transporting subunit beta 1 (ATP1B1), ATPase plasma membrane Ca2+ transporting 3 (ATP2B3), ATPase Na+/K+ transporting subunit alpha 2 (ATP1A2), perilipin 1 (PLIN1), patatin like phospholipase domain containing 3 (PNPLA3), ELOVL fatty acid elongase 5 (ELOVL5) and metabolites like epinephrine, cAMP, arachidonic acid, oleic acid, linoleic acid, and docosahexaenoic acid existed age-specificeffects and played important roles in lipolysis, fat accumulation, and fatty acid composition. Our findings provide a reference for molecular mechanisms in BF tissue development and the optimization of carcass quality.

Multi-Omics Reveals the Effect of Crossbreeding on Some Precursors of Flavor and Nutritional Quality of Pork

Over the last several decades, China has continuously introduced Duroc boars and used them as breeding boars. Although this crossbreeding method has increased pork production, it has affected pork quality. Nowadays, one of the primary goals of industrial breeding and production systems is to enhance the quality of meat. This research analyzed the molecular mechanisms that control the quality of pork and may be used as a guide for future efforts to enhance meat quality. The genetic mechanisms of cross-breeding for meat quality improvement were investigated by combining transcriptome and metabolome analysis, using Chinese native Jiaxing black (JXB) pigs and crossbred Duroc × Duroc × Berkshire × JXB (DDBJ) pigs. In the longissimus Dorsi muscle, the content of inosine monophosphate, polyunsaturated fatty acid, and amino acids were considerably higher in JXB pigs in contrast with that of DDBJ pigs, whereas DDBJ pigs have remarkably greater levels of polyunsaturated fatty acids than JXB pigs. Differentially expressed genes (DEGs) and differential metabolites were identified using transcriptomic and metabolomic KEGG enrichment analyses. Differential metabolites mainly include amino acids, fatty acids, and phospholipids. In addition, several DEGs that may explain differences in meat quality between the two pig types were found, including genes associated with the metabolism of lipids (e.g., DGKA, LIPG, and LPINI), fatty acid (e.g., ELOVL5, ELOVL4, and ACAT2), and amino acid (e.g., SLC7A2, SLC7A4). Combined with the DEGS-enriched signaling pathways, the regulatory mechanisms related to amino acids, fatty acids, and phospholipids were mapped. The abundant metabolic pathways and DEGs may provide insight into the specific molecular mechanism that regulates meat quality. Optimizing the composition of fatty acids, phospholipids, amino acids, and other compounds in pork is conducive to improving meat quality. Overall, these findings will provide useful information and further groundwork for enhancing the meat quality that may be achieved via hybrid breeding.

Integrating Single-Cell RNA-Seq and Bulk RNA-Seq Data to Explore the Key Role of Fatty Acid Metabolism in Breast Cancer

Cancer immune escape is associated with the metabolic reprogramming of the various infiltrating cells in the tumor microenvironment (TME), and combining metabolic targets with immunotherapy shows great promise for improving clinical outcomes. Among all metabolic processes, lipid metabolism, especially fatty acid metabolism (FAM), plays a major role in cancer cell survival, migration, and proliferation. However, the mechanisms and functions of FAM in the tumor immune microenvironment remain poorly understood. We screened 309 fatty acid metabolism-related genes (FMGs) for differential expression, identifying 121 differentially expressed genes. Univariate Cox regression models in The Cancer Genome Atlas (TCGA) database were then utilized to identify the 15 FMGs associated with overall survival. We systematically evaluated the correlation between FMGs' modification patterns and the TME, prognosis, and immunotherapy. The FMGsScore was constructed to quantify the FMG modification patterns using principal component analysis. Three clusters based on FMGs were demonstrated in breast cancer, with three patterns of distinct immune cell infiltration and biological behavior. An FMGsScore signature was constructed to reveal that patients with a low FMGsScore had higher immune checkpoint expression, higher immune checkpoint inhibitor (ICI) scores, increased immune microenvironment infiltration, better survival advantage, and were more sensitive to immunotherapy than those with a high FMGsScore. Finally, the expression and function of the signature key gene NDUFAB1 were examined by in vitro experiments. This study significantly demonstrates the substantial impact of FMGs on the immune microenvironment of breast cancer, and that FMGsScores can be used to guide the prediction of immunotherapy efficacy in breast cancer patients. In vitro experiments, knockdown of the NDUFAB1 gene resulted in reduced proliferation and migration of MCF-7 and MDA-MB-231 cell lines.

Proteomic analysis reveals mechanisms underlying increased efficacy of bleomycin by photochemical internalization in bladder cancer cells

Photochemical internalization (PCI) is a promising new technology for site-specific drug delivery, developed from photodynamic therapy (PDT). In PCI, light-induced activation of a photosensitizer trapped inside endosomes together with e.g. chemotherapeutics, nucleic acids or immunotoxins, allows cytosolic delivery and enhanced local therapeutic effect. Here we have evaluated the photosensitizer meso-tetraphenyl chlorine disulphonate (TPCS2a/fimaporfin) in a proteome analysis of AY-27 rat bladder cancer cells in combination with the chemotherapeutic drug bleomycin (BML). We find that BLMPCI attenuates oxidative stress responses induced by BLM alone, while concomitantly increasing transcriptional repression and DNA damage responses. BLMPCI also mediates downregulation of bleomycin hydrolase (Blmh), which is responsible for cellular degradation of BLM, as well as several factors known to be involved in fibrotic responses. PCI-mediated delivery might thus allow reduced dosage of BLM and alleviate unwanted side effects from treatment, including pulmonary fibrosis.

Emergence of Lipid Droplets in the Mechanisms of Carcinogenesis and Therapeutic Responses

Cancer shares common risk factors with cardiovascular diseases such as dyslipidemia, obesity and inflammation. In both cases, dysregulations of lipid metabolism occur, and lipid vesicles emerge as important factors that can influence carcinogenesis. In this review, the role of different lipids known to be involved in cancer and its response to treatments is detailed. In particular, lipid droplets (LDs), initially described for their role in lipid storage, exert multiple functions, from the physiological prevention of LD coalescence and regulation of endoplasmic reticulum homeostasis to pathological involvement in tumor progression and aggressiveness. Analysis of LDs highlights the importance of phosphatidylcholine metabolism and the diversity of lipid synthesis enzymes. In many cancers, the phosphatidylcholine pathways are disrupted, modifying the expression of genes coding for metabolic enzymes. Tumor microenvironment conditions, such as hypoxia, different types of stress or inflammatory conditions, are also important determinants of LD behavior in cancer cells. Therefore, LDs represent therapeutic targets in cancer, and many lipid mediators have emerged as potential biomarkers for cancer onset, progression, and/or resistance.

Biosynthesis and Significance of Fatty Acids, Glycerophospholipids, and Triacylglycerol in the Processes of Glioblastoma Tumorigenesis

One area of glioblastoma research is the metabolism of tumor cells and detecting differences between tumor and healthy brain tissue metabolism. Here, we review differences in fatty acid metabolism, with a particular focus on the biosynthesis of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA) by fatty acid synthase (FASN), elongases, and desaturases. We also describe the significance of individual fatty acids in glioblastoma tumorigenesis, as well as the importance of glycerophospholipid and triacylglycerol synthesis in this process. Specifically, we show the significance and function of various isoforms of glycerol-3-phosphate acyltransferases (GPAT), 1-acylglycerol-3-phosphate O-acyltransferases (AGPAT), lipins, as well as enzymes involved in the synthesis of phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidylinositol (PI), and cardiolipin (CL). This review also highlights the involvement of diacylglycerol O-acyltransferase (DGAT) in triacylglycerol biosynthesis. Due to significant gaps in knowledge, the GEPIA database was utilized to demonstrate the significance of individual enzymes in glioblastoma tumorigenesis. Finally, we also describe the significance of lipid droplets in glioblastoma and the impact of fatty acid synthesis, particularly docosahexaenoic acid (DHA), on cell membrane fluidity and signal transduction from the epidermal growth factor receptor (EGFR).

Hepatic transcriptome analysis reveals that elovl5 deletion promotes PUFA biosynthesis and deposition

The safe and low-cost acquisition of polyunsaturated fatty acids (PUFAs) has become a research hotspot. Fatty acyl elongase 5 (Elovl5), a rate-limiting enzyme for fatty acid elongation, is principally in charge of extending C18 and C20 PUFA substrates. However, the role of elovl5 in regulating pathways and genes involved in PUFA synthesis remain largely unknown. Here, hepatic transcriptome analysis of wild-type and elovl5 knockout (elovl5^-/-) zebrafish was performed to identify the potential regulatory targets related to PUFA deposition and synthesis. There were 1579 differentially expressed genes (DEGs), of which 787 had their expression levels increased while 792 had the opposite effect. Peroxisome proliferators-activated receptors (PPAR) signaling pathway was considerably enriched in DEGs, according to the KEGG analysis, in which fatp2, fabp7, and pparδ were engaged in PUFA absorption and deposition. Additionally, transcriptome analysis also revealed that cyp46a1 and cyp2r1 were implicated in the synthesis of bile acids and the metabolism of vitamin D, thus indirectly participating in PUFA biosynthesis and deposition. Finally, the DEGs, which improve PUFA level following elovl5 deletion, were verified through feeding experiment with two prepared diets soybean oil diet and linolenic acid oil diet. This study revealed potential regulatory targets that improve PUFA level after elovl5 deletion in teleosts.

Emerging roles of polyunsaturated fatty acid synthesis pathway in colorectal cancer

The development of colorectal cancer typically involves the accumulated influences of genetic alterations, medical issues, lifestyle, and diet. Dietary fatty acids appear to affect the tumorigenesis and progression of colorectal cancer. Despite conflicting results, the current consensus on the effects of very long-chain polyunsaturated fatty acids on colorectal cancer is that low levels of eicosapentaenoic acid and docosahexaenoic acid, and high levels of arachidonic acid are associated with an increased risk of colorectal cancer. Altered levels of arachidonic acid in membrane phospholipids can change the levels of prostaglandin E₂, which affect the biological activities of cancer cells in multiple stages. Arachidonic acid and other very long-chain polyunsaturated fatty acids can affect tumorigenesis in prostaglandin E₂-independent manners as well, including stabilization of β-catenine, ferroptosis, ROS generation, regulation of transcription factors, and de novo lipogenesis. Recent studies have revealed an association between the activities of enzymes synthesizing very long-chain polyunsaturated fatty acids and tumorigenesis and cancer progression, although the mechanisms are still unknown. In this study, PUFA effects on tumorigenesis, the endogenous very long-chain polyunsaturated fatty acid synthesis pathway, metabolites of arachidonic acid and their effects on tumorigenesis and progression of CRC, and current knowledge that supports the association of the enzymes involved in the polyunsaturated fatty acid synthesis pathway with colorectal cancer tumorigenesis and progression are reviewed.