Increased expression of the gene encoding stearoyl-CoA desaturase 1 in human bladder cancer

Targeting lipid metabolism in acute myeloid leukemia: biological insights and therapeutic opportunities

Metabolic rewiring is a hallmark of malignant transformation in leukemic cells and the potential offered by its therapeutic targeting has garnered significant attention. The development of clinically relevant metabolic targeted therapies in acute myeloid leukemia (AML) has mostly focused on targeting mitochondrial energy production, but progress has been hampered by generalized toxicities. An alternative strategy is to shift the focus from targeting energy production to targeting more specialized metabolic functions, such as energy storage, the regulation of oxidative stress and availability of cofactors needed for the function of specific metabolic reactions. Lipid metabolism plays a role in many of these metabolic functions and its importance in AML maintenance and response to therapy is being increasingly recognized but needs to be adequately interpreted in the context of its interaction with the microenvironment, particularly the adipose niche. In this review, we provide an overview of our current understanding of AML cellular metabolic dependencies on fatty acid and lipid metabolism and discuss their relevance in the context of functional interactions with adipocytes. We highlight unresolved questions about how to best target lipid metabolism and suggest approaches needed to fully understand the interplay between malignant cells and their niche in the context of metabolic dependencies.

VIRMA-Mediated the m6A Methylation of SCD Facilitates Wilms' Tumor Progression via AMPK Pathway

Wilms' tumor (WT) is the most prevalent renal cancer in children. Numerous studies have shown that vir-like n6-methyladenosine (m6A) methyltransferase-associated protein (VIRMA), a necessary component and the largest methyltransferase, contributes to the advancement of multiple cancers. However, its function has not been characterized in WT. Hence, we examined the potential role of VIRMA in WT by analyzing its effect on the m6A modification of stearoyl-CoA desaturase (SCD). We utilized bioinformatics to narrow 12 differentially expressed (DE) genes in WT to a single gene. The expressions of SCD and VIRMA were analyzed via quantitative real-time PCR and western blotting. The influence of SCD on the malignancy attributes of WT cells and adenosine 5'-monophosphate-activated protein kinase (AMPK) signaling was assessed through Cell counting Kit-8, Ethynyl-2'-deoxyuridine, transwell, and western blotting assays. The specific interactions between SCD and VIRMA were confirmed through methylated RNA immunoprecipitation, western blotting, and RNA stability assays, followed by rescue experiments to show underlying mechanisms. The SCD expression was found to be elevated in WT samples. Furthermore, its silencing mitigated the malignant characteristics of WT cells while increasing the protein levels of key AMPK signaling molecules. Moreover, VIRMA was also upregulated in WT samples and demonstrated a positive association with SCD expression. The relative enrichment of SCD m6A, its protein, and its mRNA stability were enhanced in VIRMA-overexpressed WT cells. Mechanically, VIRMA overexpression accelerated the malignant phenotypes of WT cells by interacting with SCD. Overall, the results demonstrate that VIRMA-mediated m6A methylation of SCD promotes WT progression by modulating the AMPK pathway.

Stearoyl-coenzyme A desaturase enhances cell survival in human uterine leiomyoma

OBJECTIVE

Stearoyl-CoA desaturase (SCD1) is an enzyme that catalyzes the conversion of saturated delta-9 fatty acids to monounsaturated fatty acids. SCD1 is highly expressed in various cancers and facilitates cancer cell survival, tumor growth, and metastasis. This study aimed to assess SCD1 expression and function in uterine leiomyoma and matched myometrial tissue and evaluate the impact of SCD1 inhibition on leiomyoma cell viability and apoptosis.

DESIGN

Gene set enrichment analysis was performed to determine whether lipid metabolism pathways are dysregulated in leiomyoma. To assess the function of SCD1, primary leiomyoma and myometrial cells, as well as a CRISPR-engineered leiomyoma-relevant MED12 mutant human uterine smooth muscle (UtSM) cell line, were treated with SCD1 small interfering RNA or a small molecule inhibitor of SCD1, CAY10566. Cell viability and apoptosis assays, real-time quantitative polymerase chain reaction, and immunoblot analyses were performed to evaluate cell function in response to treatment.

SUBJECTS

Leiomyoma and myometrial tissues were obtained from premenopausal individuals designated female at birth (n = 30) undergoing myomectomy or hysterectomy.

EXPOSURE

SCD1 inhibition by small interfering RNA and CAY10566 treatment.

MAIN OUTCOME MEASURES

Messenger RNA (mRNA) and protein levels and cell viability and apoptosis.

RESULTS

Gene set enrichment analysis revealed that the cholesterol homeostasis pathway was significantly different in leiomyoma vs. adjacent myometrial tissues. Among the genes in this pathway, SCD1 mRNA levels were found to be significantly higher in leiomyoma than in matched myometrium. SCD1 inhibition by small interfering RNA or CAY10566 decreased antiapoptotic BCL2 mRNA and protein levels and cell viability in primary leiomyoma but not myometrial cells. SCD1 protein levels were significantly higher in the mutant MED12 UtSM cell line than in the wild-type MED12 UtSM cell line. CAY10566 treatment specifically decreased cell viability and increased apoptosis in mutant MED12 UtSM cells, with increased protein levels of cleaved caspase 3, cleaved PARP, and DDIT3 in mutant MED12 UtSM but not in wild-type MED12 UtSM cells.

CONCLUSION

SCD1, an enzyme involved in lipid homeostasis, may play an important role in promoting leiomyoma growth and represents a novel target for the treatment of leiomyoma.

Emerging insights on the role of Elovl6 in human diseases: Therapeutic challenges and opportunities

ELOVL6, elongation-of-very-long-chain-fatty acids 6, a crucial enzyme in lipid metabolism, primarily responsible for the elongation of carbon chains of C12-C16 saturated fatty acids. It plays a significant role in various human diseases, particularly those associated with metabolic disorders related to fatty acid synthesis, such as insulin resistance, non-alcoholic fatty liver disease, cancer, and cardiovascular diseases. Emerging research also links ELOVL6 to kidney diseases, neurological conditions such as epilepsy, and pulmonary fibrosis. The enzyme's expression is regulated by various factors including diet, oxidative stress, and circadian rhythms. For instance, a high-carbohydrate diet can promote an increase in ELOVL6 expression. This abnormality leads to an accumulation of long-chain fatty acids and lipid deposition, ultimately resulting in pathological consequences across multiple systems in the body. As a biological target, ELOVL6 holds promise for diagnostic and therapeutic applications, with future research expected to uncover its mechanisms and therapeutic potential, paving the way for novel interventions in multiple disease areas. Here, the expression regulation and function of ELOVL6 in various human diseases are reviewed. This review underscores ELOVL6 as a significant therapeutic target for human diseases, with its potential for diagnostic and therapeutic applications anticipated to drive future research and enable innovative interventions in various pathological conditions.

ELOVL6 promotes the progression of head and neck squamous cell carcinoma via activating WNT/β-catenin pathway

This study was to explore the role of ELOVL6 in the development of head and neck squamous cell carcinoma (HNSCC). Considering its previously identified oncogenic role in hepatocellular carcinoma. ELOVL6 gene expression, clinicopathological analysis, enrichment analysis, and immune infiltration analysis were based on the data from Gene Expression Omnibus and The Cancer Genome Atlas, with additional bioinformatics analyses performed. Human HNSCC tissue microarray and cell lines were used. The expression of ELOVL6 in HNSCC was detected by quantitative polymerase chain reaction, immunohistochemistry assay, and western blot analysis. The proliferation ability of HNSCC cells, invasion, and apoptosis were evaluated using cell counting kit-8 method, Transwell assay, and flow cytometry, respectively. Based on the data derived from the cancer databases and our HNSCC cell and tissue studies, we found that ELOVL6 was overexpressed in HNSCC. Moreover, ELOVL6 expression level had a positive correlation with clinicopathology of HNSCC. Gene set enrichment analysis showed that ELOVL6 affected the occurrence of HNSCC through WNT signaling pathway. Functional experiments demonstrated that ELOVL6 knockdown inhibited the proliferation and invasion of HNSCC cells while promoting apoptosis. Additionally, compound 3f, an agonist of WNT/β-catenin signaling pathway, enhances the effect of ELOVL6 on the progression of HNSCC cells. ELOVL6 is upregulated in HNSCC and promotes the development of HNSCC cells by inducing WNT/β-catenin signaling pathway. ELOVL6 stands a potential target for the treatment of HNSCC and a prognosis indicator of human HNSCC.

Targeting fatty acid uptake and metabolism in cancer cells: A promising strategy for cancer treatment

Despite scientific development, cancer is still a fatal disease. The development of cancer is thought to be significantly influenced by fatty acids. Several mechanisms that control fatty acid absorption and metabolism are reported to be altered in cancer cells to support their survival. Cancer cells can use de novo synthesis or uptake of extracellular fatty acid if one method is restricted. This factor makes it more difficult to target one pathway while failing to treat the disease properly. Side effects may also arise if several inhibitors simultaneously target many targets. If a viable inhibitor could work on several routes, the number of negative effects might be reduced. Comparative investigations against cell viability have found several potent natural and manmade substances. In this review, we discuss the complex roles that fatty acids play in the development of tumors and the progression of cancer, newly discovered and potentially effective natural and synthetic compounds that block the uptake and metabolism of fatty acids, the adverse side effects that can occur when multiple inhibitors are used to treat cancer, and emerging therapeutic approaches.

Unveiling the MUFA-Cancer Connection: Insights from Endogenous and Exogenous Perspectives

Monounsaturated fatty acids (MUFAs) have been the subject of extensive research in the field of cancer due to their potential role in its prevention and treatment. MUFAs can be consumed through the diet or endogenously biosynthesized. Stearoyl-CoA desaturases (SCDs) are key enzymes involved in the endogenous synthesis of MUFAs, and their expression and activity have been found to be increased in various types of cancer. In addition, diets rich in MUFAs have been associated with cancer risk in epidemiological studies for certain types of carcinomas. This review provides an overview of the state-of-the-art literature on the associations between MUFA metabolism and cancer development and progression from human, animal, and cellular studies. We discuss the impact of MUFAs on cancer development, including their effects on cancer cell growth, migration, survival, and cell signaling pathways, to provide new insights on the role of MUFAs in cancer biology.

Downregulation of Stearoyl-CoA Desaturase 1 (SCD-1) Promotes Resistance to Imatinib in Chronic Myeloid Leukemia

Chronic myeloid leukemia (CML) is a malignant hematopoietic stem cell disease resulting in the fusion of BCR and ABL genes and characterized by the presence of the reciprocal translocation t(9;22)(q34;q11). BCR-ABL, a product of the BCR-ABL fusion gene, is a structurally active tyrosine kinase and plays an important role in CML disease pathogenesis. Imatinib mesylate (IMA) is a strong and selective BCR-ABL tyrosine kinase inhibitor. Although IMA therapy is an effective treatment, patients may develop resistance to IMA therapy over time. This study investigated the possible genetic resistance mechanisms in patients developing resistance to IMA. We did DNA sequencing in order to detect BCR-ABL mutations, which are responsible for IMA resistance. Moreover, we analyzed the mRNA expression levels of genes responsible for apoptosis, such as BCL-2, P53, and other genes (SCD-1, PTEN). In a group of CML patients resistant to IMA, when compared with IMA-sensitive CML patients, a decrease in SCD-1 gene expression levels and an increase in BCL-2 gene expression levels was observed. In this case, the SCD-1 gene was thought to act as a tumor suppressor. The present study aimed to investigate the mechanisms involved in IMA resistance in CML patients and determine new targets that can be beneficial in choosing the effective treatment. Finally, the study suggests that the SCD-1 and BCL-2 genes may be mechanisms responsible for resistance.

Stearoyl-CoA desaturase 1 as a therapeutic target for cancer: a focus on hepatocellular carcinoma

One of the main characteristics of cancer cells is the alteration in lipid composition, which is associated with a significant monounsaturated fatty acids (MUFAs) enrichment. In addition to their structural functions in newly synthesized membranes in proliferating cancer cells, these fatty acids are involved in tumorigenic signaling. Increased expression and activity of stearoyl CoA desaturase (SCD1), i.e., an enzyme converting saturated fatty acids to Δ9-monounsaturated fatty acids, has been observed in various cancer cells. This increase in expression and activity has also been associated with cancer aggressiveness and poor patient outcome. Previous studies have also indicated the SCD1 involvement in increased cancer cells proliferation, growth, migration, epithelial to mesenchymal transition, metastasis, chemoresistance, and maintenance of cancer stem cells properties. Hence, SCD1 seems to be a player in malignancy development and may be considered a novel therapeutic target in cancers, including hepatocellular carcinoma (HCC). This review study aims to discuss the impact of SCD1 as a major component in lipid signaling in HCC.

Targeting stearoyl-CoA desaturase in solid tumors

Cancer cells are demarcated from normal cells by distinct biological hallmarks, including the reprogramming of metabolic processes. One of the key players involved in metabolic reprogramming is stearoyl-CoA desaturase (SCD), which converts saturated fatty acids to monounsaturated fatty acids in an oxygen-dependent reaction that is crucial for maintaining fatty acid homeostasis. As such, SCD has been identified as a potential therapeutic target in numerous types of cancers, and its inhibition suppresses cancer cell growth in vitro and in vivo. This review summarizes the evidence implicating SCD in cancer progression and proposes novel therapeutic strategies for targeting SCD in solid tumors.

Effects of dapagliflozin on adipose and liver fatty acid composition and mRNA expression involved in lipid metabolism in high-fat-fed rats

BACKGROUND

SGLT2 inhibitor enhances not only glucose excretion but also fatty acid utilization. Those facts suggest that SGLT2 inhibitor affects fat accumulation and lipid storage.

OBJECTIVE

In the present study, we evaluated the effects of dapagliflozin on fatty acid composition and gene expression involved in fatty acid metabolism in rat adipose and liver tissues.

METHODS

We administered 1 mg/kg/day dapagliflozin for 7 weeks to male high-fat-fed rats (DAPA group), and then weights and 22 fatty acid contents in the epididymal (EPI), mesenteric (MES), retroperitoneal (RET) and subcutaneous (SUB) adipose tissues, and the liver were compared with vehicle-administered control group.

RESULTS

In the EPI, RET, and SUB in the DAPA group, contents of several fatty acids were lower (P<0.05) than those in the control group while no significant difference was detected in tissue weight. In the MES, not only tissue weight but also wide variety of fatty acid contents including saturated, monounsaturated, and polyunsaturated fatty acids were lower (P<0.05). As for the liver tissue, no significant difference was observed in fatty acid contents between the groups. mRNA expression of Srebp1c in EPI was significantly higher (P<0.05) in the DAPA group than in the control group, while Scd1 expression in the liver was lower (P<0.01).

CONCLUSION

These results suggest that dapagliflozin might suppress lipid accumulation especially in the MES, and could reduce contents of fatty acids not in the liver but in adipose tissues in high-fat-fed rats. In addition, dapagliflozin could influence mRNA expression involved in lipogenesis in the EPI and liver.

Metabolic Reprogramming of Thyroid Cancer Cells and Crosstalk in Their Microenvironment

Metabolism differs significantly between tumor and normal cells. Metabolic reprogramming in cancer cells and metabolic interplay in the tumor microenvironment (TME) are important for tumor formation and progression. Tumor cells show changes in both catabolism and anabolism. Altered aerobic glycolysis, known as the Warburg effect, is a well-recognized characteristic of tumor cell energy metabolism. Compared with normal cells, tumor cells consume more glucose and glutamine. The enhanced anabolism in tumor cells includes de novo lipid synthesis as well as protein and nucleic acid synthesis. Although these forms of energy supply are uneconomical, they are required for the functioning of cancer cells, including those in thyroid cancer (TC). Increasing attention has recently focused on alterations of the TME. Understanding the metabolic changes governing the intricate relationship between TC cells and the TME may provide novel ideas for the treatment of TC.

Alterations in complex lipids in tumor tissue of patients with colorectal cancer

Background

Accumulating evidence indicates alterations in lipid metabolism and lipid composition in neoplastic tissue. Earlier nuclear magnetic resonance studies showed that the contents of major lipid groups, such as triacylglycerols, phospholipids and cholesterol, are changed in colon cancer tissue.

Methods

In this study, a more detailed analysis of lipids in cancer and tumor adjacent tissues from colorectal cancer patients, using liquid chromatography–mass spectrometry, allowed for comparison of 199 different lipids between cancer tissue and tumor adjacent tissue using principal component analysis.

Results

Significant differences were found in 67 lipid compounds between the two types of tissue; many of these lipid compounds are bioactive lipids such as ceramides, lysophospholipids or sterols and can influence the development of cancer. Additionally, increased levels of phospholipids and sphingolipids were present, which are major components of the cell membrane, and increases in these lipids can lead to changes in cell membrane properties.

Conclusions

This study showed that many complex lipids are significantly increased or decreased in colon cancer tissue, reflecting significant alterations in lipid metabolism. This knowledge can be used for the selection of potential molecular targets of novel anticancer strategies based on the modulation of lipid metabolism and the composition of the cell membrane in colorectal cancer cells.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-021-01512-x.

Emerging Biomarkers for Predicting Bladder Cancer Lymph Node Metastasis

Bladder cancer is one of the leading causes of cancer deaths worldwide. Early detection of lymph node metastasis of bladder cancer is essential to improve patients' prognosis and overall survival. Current diagnostic methods are limited, so there is an urgent need for new specific biomarkers. Non-coding RNA and m6A have recently been reported to be abnormally expressed in bladder cancer related to lymph node metastasis. In this review, we tried to summarize the latest knowledge about biomarkers, which predict lymph node metastasis in bladder cancer and their mechanisms. In particular, we paid attention to the impact of non-coding RNA on lymphatic metastasis of bladder cancer and its specific molecular mechanisms, as well as some prediction models based on imaging, pathology, and biomolecules, in an effort to find more accurate diagnostic methods for future clinical application.

Saturated Fatty Acid Intake Is Associated With Increased Inflammation, Conversion of Kynurenine to Tryptophan, and Delta-9 Desaturase Activity in Healthy Humans

Saturated fat ingestion has previously been linked to increases in inflammation. However the relationship between saturated fatty acid (SFA) intake and the kynureine:tryptophan ratio ([Kyn]:[Trp]), a marker of inflammation, has not been previously investigated. This study evaluated in healthy, middle aged, individuals (men = 48, women = 52), potential relationships between SFA intake, red blood cell (RBC) membrane SFAs and monounsaturated fatty acids (MUFA), the [Kyn]:[Trp] ratio, C-reactive protein (CRP), TNF-α and Δ9 desaturase activity. [Kyn]:[Trp] was positively associated with increases in Total fat (P = .034) intake, including Total SFA (P = .029) and Total MUFA (P = .042) intakes. Unexpectedly the [Kyn]:[Trp] ratio was inversely associated with the percentage of Total SFA (P = .004) and positively associated with percentage of Total MUFA (P = .012) present in the RBC membrane. We found a positive association between Δ9 desaturase activity, responsible for the desaturation of a various SFAs to MUFAs, and [Kyn]:[Trp] (P = .008). [Kyn]:[Trp] was also positively associated with CRP (P = .044), however no significant relationship between [Kyn]:[Trp] and TNF-α was found. This study shows for the first time that SFA consumption increases inflammatory pathways linked to increased tryptophan to kynurenine conversion, even in healthy humans. Our data also suggests that SFA linked increases in inflammation occur concomitantly with an upregulation of Δ9 desaturase activity resulting in increased desaturation of SFA substrates to their MUFA derivatives.

The Lipid Metabolic Landscape of Cancers and New Therapeutic Perspectives

Lipid metabolism reprograming, as a hallmark of malignancy, has received renewed interest in recent years in such areas as energy sources, cell membrane components, and signaling molecules involved in the rapid tumor growth and the adaptation to the tumor microenvironment. Lipid metabolism deregulation in cancer involves multiple aspects, including an increased lipid uptake, endogenous de novo fatty acid synthesis, fatty acid oxidation, and cholesterol accumulation, thereby promoting tumor growth and progression. Recent advances in the understanding of specific metabolic alterations in cancer reveal novel pathogenesis mechanisms and a growing number of drugs targeting lipid metabolism have been applied in anti-tumor therapy. Thus, this review discusses the lipid metabolic landscape of cancers and the interplay with oncogenic signaling, and summarizes potential therapeutic targets to improve the therapeutic efficiency in cancer patients, in order to provide more reference and thinking for the treatment of lipid metabolism of cancer patients.

Lipid metabolism in colon cancer: Role of Liver X Receptor (LXR) and Stearoyl-CoA Desaturase 1 (SCD1)

Colorectal cancer (CRC) is one of the most commonly occurring cancers worldwide. Although several genetic alterations have been associated with CRC onset and progression, nowadays the reprogramming of cellular metabolism has been recognized as a fundamental step of the carcinogenic process. Intestinal tumor cells frequently display an aberrant activation of lipid metabolism. Indeed, to satisfy the growing needs of a continuous proliferation, cancer cells can either increase the uptake of exogenous lipids or upregulate the endogenous lipogenesis and cholesterol synthesis. Therefore, strategies aimed at limiting lipid accumulation are now under development in order to counteract malignancies. Two major players of lipids metabolism have been so far identified for their contribution to CRC development: the nuclear receptor Liver X Receptor (LXRs) and the enzyme Stearoyl-CoA Desaturase 1 (SCD1). Whereas LXR is mainly recognized for its role as a cholesterol sensor, finally promoting the loss of cellular cholesterol and whole-body homeostasis, SCD1 acts as the major regulator of new fatty acids, finely tuning the monounsaturated fatty acids (MUFA) to saturated fatty acids (SFA) ratio. Intriguingly, SCD1 is directly regulated by LXRs. Despite LXRs agonists have elicited great interest as a promising therapeutic target for cancer, LXR's ability to induce SCD1 and new fatty acids synthesis represent a major obstacle in the development of new effective treatments. Thus, further investigations are required to fully dissect the concomitant modulation of both players, to develop specific therapies aimed at blocking intestinal cancer cells proliferation, eventually counteracting CRC progression.

Lipids and cancer: Emerging roles in pathogenesis, diagnosis and therapeutic intervention

With the advent of effective tools to study lipids, including mass spectrometry-based lipidomics, lipids are emerging as central players in cancer biology. Lipids function as essential building blocks for membranes, serve as fuel to drive energy-demanding processes and play a key role as signaling molecules and as regulators of numerous cellular functions. Not unexpectedly, cancer cells, as well as other cell types in the tumor microenvironment, exploit various ways to acquire lipids and extensively rewire their metabolism as part of a plastic and context-dependent metabolic reprogramming that is driven by both oncogenic and environmental cues. The resulting changes in the fate and composition of lipids help cancer cells to thrive in a changing microenvironment by supporting key oncogenic functions and cancer hallmarks, including cellular energetics, promoting feedforward oncogenic signaling, resisting oxidative and other stresses, regulating intercellular communication and immune responses. Supported by the close connection between altered lipid metabolism and the pathogenic process, specific lipid profiles are emerging as unique disease biomarkers, with diagnostic, prognostic and predictive potential. Multiple preclinical studies illustrate the translational promise of exploiting lipid metabolism in cancer, and critically, have shown context dependent actionable vulnerabilities that can be rationally targeted, particularly in combinatorial approaches. Moreover, lipids themselves can be used as membrane disrupting agents or as key components of nanocarriers of various therapeutics. With a number of preclinical compounds and strategies that are approaching clinical trials, we are at the doorstep of exploiting a hitherto underappreciated hallmark of cancer and promising target in the oncologist's strategy to combat cancer.

Identification of GSN and LAMC2 as Key Prognostic Genes of Bladder Cancer by Integrated Bioinformatics Analysis

Bladder cancer is a common malignancy with mechanisms of pathogenesis and progression. This study aimed to identify the prognostic hub genes, which are the central modulators to regulate the progression and proliferation in the specific subtype of bladder cancer. The identification of the candidate hub gene was performed by weighted gene co-expression network analysis to construct a free-scale gene co-expression network. The gene expression profile of GSE97768 from the Gene Expression Omnibus database was used. The association between prognosis and hub gene was evaluated by The Cancer Genome Atlas database. Four gene-expression modules were significantly related to bladder cancer disease: the red module (human adenocarcinoma lymph node metastasis), the darkturquioise module (grade 2 carcinoma), the lightgreen module (grade 3 carcinoma), and the royalblue module (transitional cell carcinoma lymphatic metastasis). Based on betweenness centrality and survival analysis, we identified laminin subunit gamma-2 (LAMC2) in the grade 2 carcinoma, gelsolin (GSN) in the grade 3 carcinoma, and homeodomain-interacting protein kinase 2 (HIPK2) in the transitional cell carcinoma lymphatic metastasis. Subsequently, the protein levels of LAMC2 and GSN were respectively down-regulated and up-regulated in tumor tissue with the Human Protein Atlas (HPA) database. Our results suggested that LAMC2 and GSN are the central modulators to transfer information in the specific subtype of the disease.

Trichothecin inhibits invasion and metastasis of colon carcinoma associating with SCD-1-mediated metabolite alteration

Lipid metabolic abnormalities have received intensified concerns and increased de novo synthesis of lipids is recognized as a common feature of many human cancers. Nevertheless, the role of lipid metabolism that confers aggressive properties on human cancers still remains to be revealed. Natural compounds represent an abundant pool of agents for the discovery of novel lead compounds. Trichothecin (TCN) is a sesquiterpenoid originating from an endophytic fungus of the herbal plant Maytenus hookeri Loes. Here, we assess the association of stearoyl-CoA desaturase 1 (SCD-1) over-expression with malignant progression of colorectal cancer (CRC). Based on this association, the effect of TCN on migration and invasion of colon carcinoma cells closely related to the inhibition of SCD-1 is evaluated. We further demonstrate that reduced production of unsaturated fatty acids (FAs) by blocking SCD-1 activity is beneficial for the anti-invasion effect of TCN. The aim of this study was to clarify the mechanistic connection between metabolite alterations induced by metabolic rewiring and the aggressive tumor phenotype and further develop novel pharmacological tools for the intervention of tumor invasion associated with SCD-1-mediated metabolite alterations.

Stearoyl-CoA desaturase and tumorigenesis

Stearoyl-CoA desaturase (SCD) generates monounsaturated fatty acids (MUFAs) which contribute to cell growth, survival, differentiation, metabolic regulation and signal transduction. Overexpression of SCD is evident and implicated in metabolic diseases such as diabetes and non-alcoholic fatty liver disease. SCD also stimulates canonical Wnt pathway and YAP activation in support of stemness and tumorigenesis. SCD facilitates metabolic reprogramming in cancer which is mediated, at least in part, by regulation of AKT, AMPK, and NF-kB via MUFAs. Our research has revealed the novel positive loop to amplify Wnt signaling through stabilization of LRP5/6 in both hepatic stellate cells and liver tumor-initiating stem cell-like cells. As such, this loop is pivotal in promoting liver fibrosis and liver tumor development. This review summarizes the mechanisms of SCD-mediated tumor promotion described by recent studies and discusses the future prospect for SCD-mediated signaling crosstalk as a potential therapeutic target for cancer.

Lineage-Restricted Regulation of SCD and Fatty Acid Saturation by MITF Controls Melanoma Phenotypic Plasticity

Phenotypic and metabolic heterogeneity within tumors is a major barrier to effective cancer therapy. How metabolism is implicated in specific phenotypes and whether lineage-restricted mechanisms control key metabolic vulnerabilities remain poorly understood. In melanoma, downregulation of the lineage addiction oncogene microphthalmia-associated transcription factor (MITF) is a hallmark of the proliferative-to-invasive phenotype switch, although how MITF promotes proliferation and suppresses invasion is poorly defined. Here, we show that MITF is a lineage-restricted activator of the key lipogenic enzyme stearoyl-CoA desaturase (SCD) and that SCD is required for MITF^High melanoma cell proliferation. By contrast MITF^Low cells are insensitive to SCD inhibition. Significantly, the MITF-SCD axis suppresses metastasis, inflammatory signaling, and an ATF4-mediated feedback loop that maintains de-differentiation. Our results reveal that MITF is a lineage-specific regulator of metabolic reprogramming, whereby fatty acid composition is a driver of melanoma phenotype switching, and highlight that cell phenotype dictates the response to drugs targeting lipid metabolism.

Stearoyl-CoA Desaturase 1 as a Therapeutic Target for the Treatment of Cancer

A distinctive feature of cancer cells of various origins involves alterations of the composition of lipids, with significant enrichment in monounsaturated fatty acids. These molecules, in addition to being structural components of newly formed cell membranes of intensely proliferating cancer cells, support tumorigenic signaling. An increase in the expression of stearoyl-CoA desaturase 1 (SCD1), the enzyme that converts saturated fatty acids to ∆9-monounsaturated fatty acids, has been observed in a wide range of cancer cells, and this increase is correlated with cancer aggressiveness and poor outcomes for patients. Studies have demonstrated the involvement of SCD1 in the promotion of cancer cell proliferation, migration, metastasis, and tumor growth. Many studies have reported a role for this lipogenic factor in maintaining the characteristics of cancer stem cells (i.e., the population of cells that contributes to cancer progression and resistance to chemotherapy). Importantly, both the products of SCD1 activity and its direct impact on tumorigenic pathways have been demonstrated. Based on these findings, SCD1 appears to be a significant player in the development of malignant disease and may be a promising target for anticancer therapy. Numerous chemical compounds that exert inhibitory effects on SCD1 have been developed and preclinically tested. The present review summarizes our current knowledge of the ways in which SCD1 contributes to the progression of cancer and discusses opportunities and challenges of using SCD1 inhibitors for the treatment of cancer.

Changes in lipids composition and metabolism in colorectal cancer: a review

Altered metabolism of lipids is currently considered a hallmark characteristic of many malignancies, including colorectal cancer (CRC). Lipids are a large group of metabolites that differ in terms of their fatty acid composition. This review summarizes recent evidence, documenting many alterations in the content and composition of fatty acids, polar lipids, oxylipins and triacylglycerols in CRC patients' sera, tumor tissues and adipose tissue. Some of altered lipid molecules may be potential biomarkers of CRC risk, development and progression. Owing to a significant role of many lipids in cancer cell metabolism, some of lipid metabolism pathways may also constitute specific targets for anti-CRC therapy.