ω-3 and ω-6 Polyunsaturated Fatty Acids Regulate the Proliferation, Invasion and Angiogenesis of Gastric Cancer Through COX/PGE Signaling Pathway

The Impact of Polyunsaturated Fatty Acids in Cancer and Therapeutic Strategies

PURPOSE OF REVIEW

Cancer is a disease influenced by both genetic and environmental factors, with dietary lipids being a significant contributing factor. This review summarizes the role of polyunsaturated fatty acids (PUFAs) in the mechanism of tumor occurrence and development, and elucidate the role of PUFAs in tumor treatment.

RECENT FINDINGS

PUFAs exert their impact on cancer through altering lipid composition in cell membranes, interacting with cell membrane lipid receptors, directly modulating gene expression in the cell nucleus, and participating in the metabolism of lipid mediators. Most omega-3 PUFAs are believed to inhibit cell proliferation, promote cancer cell death, suppress cancer metastasis, alter energy metabolism, inhibit tumor microenvironment inflammation, and regulate immune responses involving macrophages, T cells, NK cells, and others. However, certain omega-6 PUFAs exhibit weaker anti-tumor effects and may even promote tumor development, such as by fostering inflammatory tumor microenvironment and enhancing tumor cell proliferation. PUFAs play important roles in hallmarks of cancer including tumor cell proliferation, cell death, migration and invasion, energy metabolism remodeling, epigenetics, and immunity. These findings provide insights into the mechanisms of cancer development and offers options for dietary management of cancer.

Anticancer Effects of Nervonic Acid in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) has no therapeutic target; therefore, treatment is restricted to anticancer agents. However, TNBC is highly drug-resistant, meaning that novel therapeutic drugs for TNBC are required. Fatty acids can both inhibit and promote different cancers. Nervonic acid (NA) is a monovalent unsaturated fatty acid with anti-inflammatory effects, although its effect on cancer is unknown. Therefore, this study investigated the effect of NA on TNBC. BT-549 cells, a TNBC cell line, were exposed to different concentrations of NA (1, 10, 100, and 1000 µM) or a control (dimethylsulfoxide). In addition, 9-week-old, female BALB/cSlc-nu/nu mice had a BT-549 cell transplant into the right side of the fourth mammary fat pad before being administered NA (100 mg/kg) or sterile tap water for 1 week. Increasing NA concentrations reduced the viability of BT-549 cells. At 100 µM, NA increased the expression of single-stranded DNA, a marker of apoptosis; decreased the expression of nuclear factor-κ B, an apoptosis inhibitor; and decreased the expression of Ki-67, a marker of proliferation. Furthermore, 10 µM NA inhibited cell migration and invasion of BT-549 cells via a non-significant increase in the mRNA expression of E-cadherin (CDH1) and significant decreases in the mRNA expression of N-cadherin (CDH2) and the protein expression of matrix metalloproteinase-9 and 2. In addition, the growth and metastasis to the lungs of mammary gland tumors were significantly lower in NA-treated mice than in control mice. These results suggest that NA has an antitumor effect both in vitro and in vivo; therefore, NA may be a novel therapeutic agent for TNBC.

Relationships of omega-3 and omega-6 polyunsaturated fatty acids with esophageal diseases: a two-sample Mendelian randomization analysis

Introduction

Omega-3 polyunsaturated fatty acids (PUFAs) have been widely studied and used as nutritional supplements because of their anti-inflammatory effects. Previous studies have shown an association between polyunsaturated fatty acids such as omega-3 and omega-6 PUFAs with the development of malignant tumors. However, the relationships of omega-3 and omega-6 PUFAs with esophageal diseases have not been characterized.

Methods

Mendelian randomization (MR) is a statistical method for identifying instrumental variables (IVs) from genome-wide association study (GWAS) data, and is associated with little confounding by environmental or other disease-related factors. We used genome-wide association study (GWAS) data from previously published studies on circulating concentrations of omega-3, omega-6, docosahexaenoic acid (DHA) and linoleic acid (LA), as well as esophageal cancer and other esophageal diseases, which were downloaded from the IEU OpenGwas database (https://gwas.mrcieu.ac.uk/) and the GWAS Catalog database (https://www.ebi.ac.uk/). The inverse variance-weighted approach was used as the principal analysis, and the MR-Egger and weighted median methods were used alongside. A series of sensitivity analyses were used to ensure the robustness of the causality estimates.

Results

We found that the circulating omega-3 PUFAs concentration was positively associated with esophageal cancer (p = 8 × 10-4), and circulating DHA concentration (the main component of omega-3 in food), was also positively associated with esophageal cancer (p = 2 × 10-2), but no significant association was found between circulating omega-6 PUFAs and esophageal cancer (p = 0.17), and circulating LA concentration (the main component of omega-6 in food), was also no significant associated with esophageal cancer (p = 0.32). We found no significant relationships of circulating omega-3 and omega-6 PUFAs concentration with four other esophageal diseases.

Conclusion

This study indicates that higher levels of circulating omega-3 PUFAs and DHA concentrations may be a risk factor for the development of esophageal cancer. Conversely, an increased omega-6/omega-3 ratio may serve as a protective factor against esophageal cancer. These findings have significant implications for the clinical application of omega-3 PUFAs and the prevention and treatment of esophageal cancer.

Omega-9 monounsaturated fatty acids: a review of current scientific evidence of sources, metabolism, benefits, recommended intake, and edible safety

Omega-9 monounsaturated fatty acids (ω-9 MUFAs) are a group of unsaturated fatty acids with a unique double bond in the 9th position at the end of the methyl group terminal, having the same double bond location but different carbon chain lengths. Although knowledge about ω-9 MUFAs is constantly being updated, problems with its integration remain in the field. The review summarizes the natural sources, biosynthesis, and catabolic properties of ω-9 MUFAs, emphasizing their positive effects on health functions as well as the active intermediates produced during their metabolic processes. Subsequently, the gap between the actual consumption and recommended intake of ω-9 MUFAs in our daily diet was calculated, and their food safety and potential challenges were discussed. Finally, the outlook of potential future applications and possible research trends are presented. The review aims to promote the rational consumption of ω-9 MUFAs, provide references for their application as functional foods and clinical auxiliary special medical foods, and propose more ideas and possibilities for future scientific research.

CD36: The Bridge between Lipids and Tumors

It has been found that the development of some cancers can be attributed to obesity, which is associated with the excessive intake of lipids. Cancer cells undergo metabolic reprogramming, shifting from utilizing glucose to fatty acids (FAs) for energy. CD36, a lipid transporter, is highly expressed in certain kinds of cancer cells. High expressions of CD36 in tumor cells triggers FA uptake and lipid accumulation, promoting rapid tumor growth and initiating metastasis. Meanwhile, immune cells in the tumor microenvironment overexpress CD36 and undergo metabolic reprogramming. CD36-mediated FA uptake leads to lipid accumulation and has immunosuppressive effects. This paper reviews the types of FAs associated with cancer, high expressions of CD36 that promote cancer development and progression, effects of CD36 on different immune cells in the tumor microenvironment, and the current status of CD36 as a therapeutic target for the treatment of tumors with high CD36 expression.

LncRNA LINC01278 Regulates the Prognosis and Related Mechanisms of Gastric Cancer by Targeting miR-129-5p

Gastric cancer, a prevalent malady within the digestive tract, has a complex pathological mechanism and numerous patients. The regulation of gastric cancer process by long non-coding RNA (lncRNA) presented new prospects for the study of its molecular mechanism and the treatment of patients. The abnormal expressed genes in gastric cancer were screened by GSE193109 dataset. The correlation between LINC01278 and the likelihood of survival in patients suffering from gastric cancer was investigated by Kaplan-Meier survival curve and multivariate Cox analysis. LINC01278 in gastric cancer tissue samples and cells was verified via RT-qPCR. The cell counting kit-8 (CCK-8) and transwell assay were selected to detect the growth activity of gastric cancer cells. The association between LINC01278 and miR-129-5p was validated through luciferase reporter assay and RNA-binding protein immunoprecipitation (RIP) assay. Correlation analysis of clinical features revealed an association between LINC01278 and the prognosis in gastric cancer patients. LINC01278 was actively expressed in gastric cancer, which exerts a tumor-promoting effect. Silencing LINC01278 suppressed the biological function of tumor cells through spongiform miR-129-5p. LINC01278 has the potential to serve as a novel biomarker, offering new avenues of research for the prognosis and treatment of gastric cancer.

Fatty acid metabolism: A new therapeutic target for cervical cancer

Cervical cancer (CC) is one of the most common malignancies in women. Cancer cells can use metabolic reprogramming to produce macromolecules and ATP needed to sustain cell growth, division and survival. Recent evidence suggests that fatty acid metabolism and its related lipid metabolic pathways are closely related to the malignant progression of CC. In particular, it involves the synthesis, uptake, activation, oxidation, and transport of fatty acids. Similarly, more and more attention has been paid to the effects of intracellular lipolysis, transcriptional regulatory factors, other lipid metabolic pathways and diet on CC. This study reviews the latest evidence of the link between fatty acid metabolism and CC; it not only reveals its core mechanism but also discusses promising targeted drugs for fatty acid metabolism. This study on the complex relationship between carcinogenic signals and fatty acid metabolism suggests that fatty acid metabolism will become a new therapeutic target in CC.

The roles of COX-2 in protozoan infection

Protozoan diseases cause great harm in animal husbandry and require human-provided medical treatment. Protozoan infection can induce changes in cyclooxygenase-2 (COX-2) expression. The role played by COX-2 in the response to protozoan infection is complex. COX-2 induces and regulates inflammation by promoting the synthesis of different prostaglandins (PGs), which exhibit a variety of biological activities and participate in pathophysiological processes in the body in a variety of ways. This review explains the roles played by COX-2 in protozoan infection and analyzes the effects of COX-2-related drugs in protozoan diseases.