Macronutrients, fatty acids, cholesterol and renal cell cancer risk

Association of saturated fatty acids with cancer risk: a systematic review and meta-analysis

OBJECTIVE

Extensive research has explored the link between saturated fatty acids (SFAs) and cardiovascular diseases, alongside other biological dysfunctions. Yet, their association with cancer risk remains a topic of debate among scholars. The present study aimed to elucidate this association through a robust meta-analysis.

METHODS

PubMed, Embase, Cochrane Library, and Web of Science databases were searched systematically to identify relevant studies published until December 2023. The Newcastle-Ottawa Scale was used as the primary metric for evaluating the quality of the included studies. Further, fixed- or random-effects models were adopted to determine the ORs and the associated confidence intervals using the Stata15.1 software. The subsequent subgroup analysis revealed the source of detection and the cancer types, accompanied by sensitivity analyses and publication bias evaluations.

RESULTS

The meta-analysis incorporated 55 studies, comprising 38 case-control studies and 17 cohort studies. It revealed a significant positive correlation between elevated levels of total SFAs and the cancer risk (OR of 1.294; 95% CI: 1.182-1.416; P-value less than 0.001). Moreover, elevated levels of C14:0, C16:0, and C18:0 were implicated in the augmentation of the risk of cancer. However, no statistically significant correlation of the risk of cancer was observed with the elevated levels of C4:0, C6:0, C8:0, C10:0, C12:0, C15:0, C17:0, C20:0, C22:0, and C24:0. Subgroup analysis showed a significant relationship between excessive dietary SFA intake, elevated blood SFA levels, and heightened cancer risk. Increased total SFA levels correlated with higher risks of breast, prostate, and colorectal cancers, but not with lung, pancreatic, ovarian, or stomach cancers.

CONCLUSION

High total SFA levels were correlated with an increased cancer risk, particularly affecting breast, prostate, and colorectal cancers. Higher levels of specific SFA subtypes (C14:0, C16:0, and C18:0) are also linked to an increased cancer risk. The findings of the present study would assist in providing dietary recommendations for cancer prevention, thereby contributing to the development of potential strategies for clinical trials in which diet-related interventions would be used in combination with immunotherapy to alter the levels of SFAs in patients and thereby improve the outcomes in cancer patients. Nonetheless, further high-quality studies are warranted to confirm these associations.

Free-Fatty Acid Receptor-4 (FFA4/GPR120) differentially regulates migration, invasion, proliferation and tumor growth of papillary renal cell carcinoma cells

Kidney cancer is among the 10 most common cancers, and renal cell carcinoma (RCC), which represent 90% of all kidney cancers, has the highest mortality rate of all genitourinary cancers. Papillary RCC (pRCC) is the second most frequent subtype of RCC and demonstrates distinct characteristics compared to other subtypes, including a high degree of metastasis and resistance to treatments against the more common clear cell RCC (ccRCC) subtype. Here, we demonstrate that the Free-Fatty Acid Receptor-4 (FFA4), a G protein-coupled receptor that is endogenously activated by medium-to-long chain free-fatty acids, is upregulated in pRCC compared to patient-matched normal kidney tissue, and that the expression of FFA4 increases with the degree of pathological grading of pRCC. Our data also show that FFA4 transcript is not expressed in ccRCC cell lines, but is expressed in the well-characterized metastatic pRCC cell line ACHN. Furthermore, we show that agonism of FFA4 with the selective agonist cpdA positively regulates ACHN cell migration and invasion in a manner dependent on PI3K/AKT/NF-κB signaling to COX-2 and MMP-9, with partial-dependence on EGFR transactivation. Our results also demonstrate that FFA4 agonism induces STAT-3-driven epithelial-mesenchymal transition, suggesting a significant role for FFA4 in pRCC metastasis. On the contrary, FFA4 agonism significantly reduces cell proliferation and tumor growth, suggesting that the receptor may have opposing effects on pRCC cell growth and migration. Together, our data demonstrate that FFA4 has significant functional roles in pRCC cells and may be an attractive target for study of pRCC and development of RCC pharmacotherapeutics.

Lipids as Targets for Renal Cell Carcinoma Therapy

Kidney cancer is among the top ten most common cancers to date. Within the kidney, renal cell carcinoma (RCC) is the most common solid lesion occurring. While various risk factors are suspected, including unhealthy lifestyle, age, and ethnicity, genetic mutations seem to be a key risk factor. In particular, mutations in the von Hippel-Lindau gene (Vhl) have attracted a lot of interest since this gene regulates the hypoxia inducible transcription factors HIF-1α and HIF-2α, which in turn drive the transcription of many genes that are important for renal cancer growth and progression, including genes involved in lipid metabolism and signaling. Recent data suggest that HIF-1/2 are themselves regulated by bioactive lipids which make the connection between lipids and renal cancer obvious. This review will summarize the effects and contributions of the different classes of bioactive lipids, including sphingolipids, glycosphingolipids, eicosanoids, free fatty acids, cannabinoids, and cholesterol to renal carcinoma progression. Novel pharmacological strategies interfering with lipid signaling to treat renal cancer will be highlighted.

Genesis and Mechanism of Some Cancer Types and an Overview on the Role of Diet and Nutrition in Cancer Prevention

Cancer is a major disease with a high mortality rate worldwide. In many countries, cancer is considered to be the second most common cause of death after cardiovascular disease. The clinical management of cancer continues to be a challenge as conventional treatments, such as chemotherapy and radiation therapy, have limitations due to their toxicity profiles. Unhealthy lifestyle and poor dietary habits are the key risk factors for cancer; having a healthy diet and lifestyle may minimize the risk. Epidemiological studies have shown that a high fruit and vegetable intake in our regular diet can effectively reduce the risk of developing certain types of cancers due to the high contents of antioxidants and phytochemicals. In vitro and in vivo studies have shown that phytochemicals exert significant anticancer effects due to their free radical scavenging capacity potential. There has been extensive research on the protective effects of phytochemicals in different types of cancers. This review attempts to give an overview of the etiology of different types of cancers and assesses the role of phytonutrients in the prevention of cancers, which makes the present review distinct from the others available.

Dietary Patterns in Italy and the Risk of Renal Cell Carcinoma

Background: Conclusive evidence on foods, nutrients, or dietary patterns and the risk of renal cell carcinoma (RCC) is lacking in the literature. Methods: We considered data from an Italian hospital-based case–control study (1992–2004) on 767 incident RCC cases and 1534 controls. A posteriori dietary patterns were identified by applying principal component factor analysis on 28 nutrients derived from a 78-item food-frequency questionnaire. We estimated the odds ratios (ORs) of RCC and corresponding 95% confidence intervals (CIs) for each quartile category (compared to the lowest one) using conditional multiple logistic regression models providing adjustment for major confounding factors. Results: We identified four dietary patterns, named “Animal products”, “Starch-rich”, “Vitamins and fiber”, and “Cooking oils and dressings”. Higher intakes of the “Starch-rich” pattern were positively associated with RCC risk (OR = 1.38, 95% CI: 1.04–1.82 for the highest quartile, p = 0.018). The association was inverse with the “Cooking oils and dressings” pattern (OR = 0.61, 95% CI: 0.47–0.80, p < 0.001), whereas no association was found with “Animal products” and “Vitamins and fiber” patterns. Conclusions: Higher intakes of starch-related foods may increase RCC risk, whereas consumption of olive and seed oils may favorably influence RCC risk.

Oleic acid promotes cell invasion through an integrin-linked kinase signaling pathway in renal cell carcinoma

The change of fatty acid composition has been regarded as an indicator of altered lipid metabolism during human tumourigenesis, but the details are still unclear. We have previously demonstrated a monounsaturated fatty acid (MUFA) named oleic acid (OA) was involved in renal cell carcinoma (RCC) cell growth, as an extracellular signaling molecule to regulate 786-O cell proliferation via the integrin-linked kinase (ILK) pathway. In this study, we further observe the effects of OA on cell invasion of RCC and the potential mechanism by which OA worked was determined. The transwell invasion assay showed OA increased cell invasion of RCC in a dose-dependent manner. Western blotting results indicated ILK, COX-2, and MMP-9 proteins were involved for their high expressions and these effects were reversed when down-regulating the expression of ILK by special siRNA. The MMPs inhibitor GM6001 could weaken the abilities of OA on RCC cells invasion. These results suggested MUFA indeed affected cell invasion of RCC, which was depended by the regulation of ILK pathway.

Glycemic index, glycemic load and carbohydrate intake in association with risk of renal cell carcinoma

Carbohydrate intake affects postprandial glucose levels and insulin response, which plays a role in carcinogenesis. The relationship between carbohydrate intake, dietary glycemic index (GI) and glycemic load (GL), and risk of renal cell carcinoma (RCC) remains unclear. We conducted a case-control study including 854 patients with newly diagnosed RCC (cases) and 1255 healthy participants (controls) recruited since 2002. GI, GL and carbohydrate intake were obtained via a validated food frequency questionnaire. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression, adjusting for potential confounders. We found that higher GI was significantly associated with RCC risk with an OR of 1.32 (95% CI, 0.99-1.74; Ptrend = 0.026) (the highest versus the lowest quartiles). We also observed an inverse association between fiber intake and RCC risk with OR of 0.70 (95% CI = 0.50-0.99) as well as between starch intake and risk of RCC with OR of 0.65 (95% CI = 0.49-0.87). Individuals with a high-GI diet and hypertension or high body mass index (BMI) had a 2.7 times (OR = 2.67, 95% CI = 1.96-3.64) and two times (OR = 1.95, 95% CI = 1.29-2.92) higher RCC risk, respectively, than those without these factors. Our findings suggest that a high-GI diet is associated with an increased risk of RCC, whereas increased fiber and starch intakes appear to be associated with a decreased risk of RCC. We found that reducing GI levels and increasing fiber intake could be a dietary strategy to decrease RCC risk, especially for individuals with hypertension or high BMI.

Dietary Inflammatory Index and Renal Cell Carcinoma Risk in an Italian Case-Control Study

BACKGROUND

The relation between diet-related inflammation and renal cell carcinoma (RCC) has not been investigated.

METHODS

In this study, we explored the association between the dietary inflammatory index (DII) and RCC in an Italian case-control study conducted between 1992 and 2004. Cases were 767 patients with incident, histologically confirmed RCC. Controls were 1534 subjects admitted to the same hospitals as cases for various acute, nonneoplastic conditions. The DII was computed based on dietary intake assessed using a reproducible and valid 78-item food frequency questionnaire. Odds ratios (ORs) were estimated through logistic regression models conditioned on age, sex, and center, and adjusted for recognized confounding factors, including total energy intake.

RESULTS

Subjects in the highest quartile of DII scores (i.e., with the most proinflammatory diets) had a higher risk of RCC compared to subjects in the lowest quartile [OR 1.41, 95% confidence interval (CI) 1.02, 1.97; p-trend = 0.04)]. Apparently stronger associations were observed among females (OR 1.68, 95% CI 0.93, 3.03), subjects aged <60 yr (OR 1.77, 95% CI 1.05, 2.98), body mass index ≥25 kg/m2 (OR 1.64, 95% CI 1.07, 2.51), and ever smokers (OR 1.66, 95% CI 1.08, 2.57), in the absence of significant heterogeneity.

CONCLUSION

A proinflammatory diet is associated with increased RCC risk.

The interplay between lipid profiles, glucose, BMI and risk of kidney cancer in the Swedish AMORIS study

With exception of cholesterol and total fat intake, associations between lipid biomarkers and kidney cancer have not often been researched. We aimed to assess possible links between lipid profiles and kidney cancer risk in a large prospective cohort study, while also taking into account glucose levels and BMI. A cohort based on 542,924 persons with baseline information on glucose, triglycerides (TGs), total cholesterol (TC) and creatinine was selected from the Swedish Apolipoprotein Mortality Risk study. A subgroup of 85,621 also had baseline measurements of HDL, LDL, apolipoprotein A-I and apoB. Multivariate Cox proportional hazard models were used to analyze associations between quartiles and dichotomized values of these lipid components and kidney cancer risk. During a mean follow-up of 13 years, 958 persons developed kidney cancer. TGs were the only lipid component for which a statistically significant association was found with kidney cancer risk when using both quartiles and a clinical cutoff (hazard ratio: 1.25 (95% CI: 0.99-1.60), 1.29 (1.01-1.66) and 1.66 (1.30-2.13) for the 2nd, 3rd and 4th quartile, compared to the 1st, with p-value for trend: <0.001). The association remained after exclusion of the 95% percentile of TG. Quartiles of glucose were also positively associated with kidney cancer risk, whereas quartiles of TC were negatively associated with kidney cancer risk. This detailed analysis of lipid components only showed a consistent relation between TG levels and kidney cancer risk. Further mechanistic studies are required to assess links between lipid abnormalities and kidney cancer.

Dietary cholesterol intake and cancer

BACKGROUND

This study assesses the association between dietary cholesterol intake and the risk of various cancers.

PATIENTS AND METHODS

Mailed questionnaires were completed between 1994 and 1997 in eight Canadian provinces by 1182 incident histologically confirmed cases of the stomach, 1727 of the colon, 1447 of the rectum, 628 of the pancreas, 3341 of the lung, 2362 of the breast, 442 of the ovary, 1799 of the prostate, 686 of the testis, 1345 of the kidney, 1029 of the bladder, 1009 of the brain, 1666 non-Hodgkin's lymphomas (NHL), 1069 leukemia and 5039 population controls. Information on dietary habits and nutrition intake were obtained using a food frequency questionnaire, which provided data on eating habits 2 years before the study. Odds ratios (ORs) were derived by unconditional logistic regression to adjust for total energy intake and other potential confounding factors.

RESULTS

Dietary cholesterol was positively associated with the risk of cancers of the stomach, colon, rectum, pancreas, lung, breast (mainly postmenopausal), kidney, bladder and NHL: the ORs for the highest versus the lowest quartile ranged from 1.4 to 1.7. In contrast, cholesterol intake was inversely associated with prostate cancer.

CONCLUSIONS

Our findings add to the evidence that high cholesterol intake is linked to increased risk of various cancers. A diet low in cholesterol may play a role in the prevention of several cancers.

A prospective analysis of the association between macronutrient intake and renal cell carcinoma in the European Prospective Investigation into Cancer and Nutrition

Previous case-control studies have suggested that a high intake of animal foods and its associated nutrients are associated with an increased risk of renal cell carcinoma, although data from prospective studies are limited. We report here on the relationship between macronutrient intake and renal cell carcinoma incidence among 435,293 participants enrolled in the European Prospective Investigation into Cancer and Nutrition. Cox proportional hazard models were used to examine the association of dietary intake of fat, protein, carbohydrate, fiber and cholesterol and risk of renal cell carcinoma adjusted for age, sex, center, height, body mass index, physical activity, education, smoking, menopausal status, alcohol and energy intake. During an average 8.8 years of follow-up, 507 renal cell carcinoma cases occurred. Risk of renal cell carcinoma was not associated with macronutrient intake, including nutrients derived from animal sources. Our results indicate that macronutrient intake is not associated with risk of renal cell carcinoma in this cohort of European men and women.

Glycemic index, glycemic load and renal cell carcinoma risk

BACKGROUND

The risk of renal cell carcinoma (RCC) has been related to refined cereals and starchy foods, but the association has not been studied in terms of glycemic index (GI) and glycemic load (GL). To provide information on this issue, we analyzed data from an Italian multicentric case-control study.

MATERIALS AND METHODS

Cases were 767 patients with histologically confirmed, incident RCC. Controls were 1534 subjects admitted to the same hospitals as cases for a wide spectrum of acute, non-neoplastic conditions, unrelated to known risk factors for RCC. Information on dietary habits was derived through a food-frequency questionnaire. Multivariate odds ratios (ORs) and 95% confidence intervals (CIs) for GI and GL intake were adjusted for major relevant covariates.

RESULTS

Compared with the lowest quintile, the ORs for the highest quintile were 1.43 (95% CI 1.05-1.95) for GI and 2.56 (95% CI 1.78-3.70) for GL, with significant trends in risk. Compared with the lowest quintile, the risk of RCC for all subsequent levels of GL was higher in never drinkers than in ever drinkers.

CONCLUSIONS

We found direct relations between dietary levels of GI and GL and RCC risk. This can be related to mechanisms linked to insulin resistance and sensitivity.