Effects of dietary fat on spontaneous metastasis of Lewis lung carcinoma in mice

Abstract

The present study assessed the effects of dietary fat on spontaneous metastasis of Lewis lung carcinoma in mice. Three-week old male C57BL/6 mice were fed the AIN-93G diet or a 45% fat diet (% kcal.) for 7 weeks before they were subcutaneously injected with 2.5 × 10⁵ viable carcinoma cells. The primary tumor was resected 2 weeks later, and mice were maintained on their respective diets for an additional 2 weeks. The high-fat diet significantly increased body weight and abdominal adipose weight compared to the AIN-93G diet. Feeding mice the 45% fat diet resulted in a two-fold increase in the number of lung metastases (P < 0.05), a 35% increase in tumor cross-sectional area, and a 50% increase in tumor volume compared to mice fed the AIN-93G diet. There were no differences in plasma concentrations of TIMP-1, IL-1β, VEGF and MCP-1 in non-tumor-bearing mice fed the AIN-93G diet or the high-fat diet, but significant increases in these cytokines in tumor-bearing mice fed the AIN-93G diet compared to the non-tumor-bearing mice fed the same diet (P < 0.05 for each comparison). Further significant increases in these cytokines in tumor-bearing mice fed the 45% fat diet compared to the same tumor-bearing mice fed the AIN-93G diet (P < 0.05 for each comparison). The high-fat diet significantly increased plasma leptin and significantly decreased plasma adiponectin compared to the AIN-93G diet in both non-tumor-bearing and tumor-bearing mice. Results of the present study demonstrated that the high-fat diet enhanced spontaneous metastasis of Lewis lung carcinoma in mice and that this aggressiveness was accompanied with significant increases in plasma concentrations of angiogenic cytokines, suggesting that dietary fat affects metastasis by promoting angiogenic processes.

Consumption of a high-fat diet abrogates inhibitory effects of methylseleninic acid on spontaneous metastasis of Lewis lung carcinoma in mice

“…Consumption of a high-fat diet increased adiposity and plasma levels of PAI-1, MCP-1, and TNF-α in non-tumor-bearing C57BL/6 mice (32), and obesity-enhanced metastasis is known to be accompanied by increases in plasma PAI-1 and MCP-1 (22). That high-fat feeding increased plasma concentrations of PAI-1, MCP-1, TNF-α, and leptin regardless of Se supplementation and that Se reduced plasma proteolytic proteases (uPA, MMP-9) and angiogenic factors (VEGF, TIMP-1) regardless of the type of diet suggest that adipose-derived inflammatory cytokines may be key determinants of the enhanced LLC aggression by high-fat feeding, which may overpower the inhibitory actions of Se on metastasis.…”

“…In clinical practice, high expressions of PAI-1 (33,34), MCP-1 (35,36), TNF-α (37), uPA (34), MMP-9 (29,38), VEGF (38), and TIMP-1 (39) have been associated with regional or distant metastasis and poor prognosis in cancer patients. Elevations of those cytokines (40)(41)(42), proteases (43,44), and angiogenic markers (22,45) have been reported in animal models of various malignancies. The present results are consistent with the existing knowledge and prove the usefulness of the LLC model to study spontaneous metastasis.…”

“…In fact, cancer patients who are obese are at a greater risk of recurrence (18,19) with shorter disease-free survival rates than nonobese patients (20). It has been shown enhanced metastasis of B16BL6 melanoma in ob/ob mice (21) and of LLC in C57BL/6 mice fed an obesigenic, high-fat diet (22), but there is no published information regarding whether obesity may affect the antimetastatic activity of dietary Se. Therefore, we conducted the following studies to test the hypothesis that obesity induced by high-fat feeding impairs the antimetastatic activity of Se.…”

Coherent anti-Stokes Raman scattering for label-free biomedical imaging

“…It has been established that obesity and a high fat diet can enhance cancer metastases within the body as excess lipids can aggravate cancer (116,117). Using the novel imaging capabilities of CARS and other NLO techniques, one can provide novel insights into the dynamics and mechanisms of cancer invasion.…”

The Use of Indigenous Green Leafy Vegetables in the Preparation of Ghanaian Dishes

“…The high dietary fiber in green leafy vegetables helps regulate the digestive system aiding bowel health and weight management. Several studies have shown that high folate intake from green leafy vegetables may lower the risk of colon polyps by 30 to 40 percent compared to low intake of this vitamin suggesting that diets low in folate may increase the risk of colon cancer [8,9]. Low folate intake has also been associated with cancers of the breast, cervix and lung.…”