linoleic-acid and Lung-Neoplasms

Ribavirin is a common antiviral drug, especially for patients with hepatitis C. Our recent studies demonstrated that ribavirin showed anti-tumor activity in colorectal cancer and hepatocellular carcinoma, but its effects on lung cancer remains unclear. This study aimed to evaluate the anti-tumor activity of ribavirin against lung cancer and elucidate the underlying mechanism. We established orthotopic mouse model of lung cancer (LLC and GLC-82) and employed an ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS)-based metabolomics approach. We found that ribavirin significantly inhibited the proliferation and colony formation of lung cancer cells. Tumor sizes of orthotopic lung cancer in ribavirin-treated groups were also significantly lower than those in control groups. Metabolomics analysis revealed that ribavirin mainly affected 5 metabolic pathways in orthotopic lung tumor models, taurine and hypotaurine metabolism, nicotinate and nicotinamide metabolism, linoleic acid metabolism, arginine biosynthesis and arachidonic acid metabolism. Furthermore, we identified 5 upregulated metabolites including β-nicotinamide adenine dinucleotide (NAD

Topics: Animals; Arachidonic Acid; Biomarkers; Chromatography, High Pressure Liquid; Linoleic Acid; Lung Neoplasms; Metabolomics; Mice; Niacinamide; Ribavirin; Taurine

Lung cancer is the most common primary malignant lung tumor. However, the etiology of lung cancer is still unclear. Fatty acids include short-chain fatty acids (SCFAs) and polyunsaturated fatty acids (PUFAs) as essential components of lipids. SCFAs can enter the nucleus of cancer cells, inhibit histone deacetylase activity, and upregulate histone acetylation and crotonylation. Meanwhile, PUFAs can inhibit lung cancer cells. Moreover, they also play an essential role in inhibiting migration and invasion. However, the mechanisms and different effects of SCFAs and PUFAs on lung cancer remain unclear. Sodium acetate, butyrate, linoleic acid, and linolenic acid were selected to treat H460 lung cancer cells. Through untargeted metabonomics, it was observed that the differential metabolites were concentrated in energy metabolites, phospholipids, and bile acids. Then, targeted metabonomics was conducted for these three target types. Three LC-MS/MS methods were established for 71 compounds, including energy metabolites, phospholipids, and bile acids. The subsequent methodology validation results were used to verify the validity of the method. The targeted metabonomics results show that, in H460 lung cancer cells incubated with linolenic acid and linoleic acid, while the content of PCs increased significantly, the content of Lyso PCs decreased significantly. This demonstrates that there are significant changes in LCAT content before and after administration. Through subsequent WB and RT-PCR experiments, the result was verified. We demonstrated a substantial metabolic disparity between the dosing and control groups, further verifying the reliability of the method.

Topics: alpha-Linolenic Acid; Chromatography, Liquid; Fatty Acids; Fatty Acids, Unsaturated; Fatty Acids, Volatile; Humans; Linoleic Acid; Lung Neoplasms; Phospholipids; Reproducibility of Results; Tandem Mass Spectrometry

In this study, the anticancer activities of two siRNA carriers were compared using a human lung adenocarcinoma epithelial cell line (A549). Firstly, poly(styrene)-graft-poly(linoleic acid) (PS-

Topics: A549 Cells; Adenocarcinoma of Lung; Drug Carriers; Humans; Linoleic Acid; Lung Neoplasms; Nanoconjugates; Plant Oils; Polyethylene Glycols; Polystyrenes; RNA, Small Interfering; RNAi Therapeutics

The distribution of omega-6 and omega-3 polyunsaturated fatty acid (PUFA) intake in Western diets is disproportionate, containing an overabundance of the omega-6 PUFA, linoleic acid (LA; C18:2). Increased enrichment with LA has been shown to contribute to the enhancement of tumorigenesis in several cancer models. Previous work has indicated that phosphatidylinositol 3-kinase (PI3K) may play a key role in LA-induced tumorigenesis. However, the modes by which LA affects carcinogenesis have not been fully elucidated. In this study, a mechanism for LA-induced upregulation of cancer cell growth is defined. LA treatment enhanced cellular proliferation in BT-474 human breast ductal carcinoma and A549 human lung adenocarcinoma cell lines. Enrichment of LA increased cyclooxygenase (COX) activity and led to increases in prostaglandin E2 (PGE2), followed by increases in matrix metalloproteinase (MMP) and transforming growth factor alpha (TGF-α) levels, which are all key elements involved in the enhancement of cancer cell growth. Further investigation revealed that LA supplementation in both BT-474 breast and A549 lung cancer cell lines greatly increased the association between the scaffolding protein GRB2-associated-binding protein 1 (Gab1) and epidermal growth factor receptor (EGFR), although Gab1 protein levels were significantly decreased. These LA-induced changes were associated with increases in activated Akt (pAkt), a downstream signaling component in the PI3K pathway. Treatment with inhibitors of EGFR, PI3K and Gab1-specific siRNAs reversed the upregulation of pAkt, as well as the observed increases in cell proliferation by LA in both cell lines. A549 xenograft assessment in athymic nude mice fed high levels of LA exhibited similar increases in EGFR-Gab1 association and increased levels of pAkt, while mice fed with high levels of the omega-3 PUFA, docosahexaenoic acid (DHA; C22:6), demonstrated an opposite response. The involvement of Gab1 in LA-induced tumorigenesis was further defined utilizing murine cell lines that express high levels of Gab1. Significant increases in cell proliferation were observed with the addition of increasing concentrations of LA. However, no changes in cell proliferation were detected in the murine paired cell lines expressing little or no Gab1 protein, establishing Gab1 as major target in LA-induced enhancement of tumorigenesis.

Topics: Adaptor Proteins, Signal Transducing; Animals; Breast Neoplasms; Carcinogenesis; Cell Line, Tumor; Cell Proliferation; Cyclooxygenase 2; Dinoprostone; Female; Humans; Linoleic Acid; Lung Neoplasms; Male; Mice; Mice, Nude; Neoplasm Transplantation; Phosphatidylinositol 3-Kinases; Transforming Growth Factor alpha

Lung cancer is the leading cause of cancer-related mortality. Surgical removal of the tumor at an early stage can be curative. However, lung cancer diagnosis at an early stage remains challenging. There is evidence that free fatty acids play a role in cancer development.. Serum samples from 55 patients with lung cancer were propensity matched with samples from 165 similar pulmonary patients without known cancer. Patients were propensity matched on age, sex, smoking history, family history of lung cancer, and chronic diseases that might affect free fatty acid levels.. Free fatty acids arachidonic acid (AA) and linoleic acid (LA) and their metabolites hydroxyeicosatetraenoic acids (HETEs)(5-HETE, 11-HETE, 12-HETE, and 15-HETE) were an estimated 1.8- to 3.3-fold greater in 37 patients with adenocarcinoma vs 111 patients without cancer (all P < .001). Areas under the receiver operating characteristic curve were significantly > 0.50, discriminating patients with lung cancer and control subjects for six of eight biomarkers and two of seven phospholipids tested, and ranged between 0.69 and 0.82 (all P < .001) for patients with lung cancer vs control subjects. AA, LA, and 15-HETE had observed sensitivity and specificity > 0.70 at the best cutpoint. Concentrations of free fatty acids and their metabolites were similar in 18 patients with squamous cell carcinoma and 54 control subjects without cancer.. Serum fatty acids and their metabolites demonstrate good sensitivity and specificity for the identification of adenocarcinoma of the lung.

Topics: Adenocarcinoma; Adult; Aged; Area Under Curve; Biomarkers; Case-Control Studies; Fatty Acids, Nonesterified; Fatty Acids, Unsaturated; Female; Humans; Hydroxyeicosatetraenoic Acids; Linoleic Acid; Lung Neoplasms; Male; Middle Aged; Phospholipids; Sensitivity and Specificity

The effects of three fatty acids on cytotoxic aggregate formation of Ca(2+)-depleted bovine alpha-lactalbumin (apo-BLA) have been studied by UV absorbance spectroscopy and transmission electron microscopy. The experimental results demonstrate that two unsaturated fatty acids, oleic acid and linoleic acid, and one saturated fatty acid, stearic acid, induce the intermediate of apo-BLA at pH 4.0-4.5 to form amorphous aggregates in time- and concentration-dependent manners. These aggregates are dissolved under physiological conditions at 37 degrees C and further characterized by fluorescence spectroscopy, circular dichroism and time-of-flight mass spectrometry. Our data here indicate that the structural characteristics of these aggregates are similar to those of HAMLET/BAMLET (human/bovine alpha-lactalbumin made lethal to tumor cells), a complex of the partially unfolded alpha-lactalbumin with oleic acid. Cell viability experiments indicate the aggregates of apo-BLA induced by oleic acid and linoleic acid show significant dose-dependent cytotoxicity to human lung tumor cells of A549 but those induced by stearic acid have no toxicity to tumor cells. Furthermore, the cytotoxic aggregates of apo-BLA induced by both unsaturated fatty acids induce apoptosis of human lung cancer cell line A549, suggesting that such cytotoxic aggregates of apo-BLA could be potential antitumor drugs. The present study provides insight into the mechanism of fatty acid-dependent oligomerization and cytotoxicity of alpha-lactalbumin, and will be helpful in the understanding of the molecular mechanism of HAMLET/BAMLET formation.

Topics: Animals; Apoptosis; Calcium; Cattle; Cell Line, Tumor; Cell Survival; Humans; Hydrogen-Ion Concentration; Lactalbumin; Linoleic Acid; Lung Neoplasms; Mass Spectrometry; Oleic Acid

New parameters that could be used as tumor markers for lung cancer would be valuable. Our aim was to analyze the fatty acid profiles of total lipids from erythrocytes and platelets from patients with advanced non-small cell lung cancer (NSCLC), chronic obstructive pulmonary disease (COPD) and asthma to reveal the fatty acids that could be used as NSCLC biomarkers. In our study, 50, 15 and 15 patients with advanced NSCLC, COPD and asthma and 50 healthy subjects were enrolled. Fatty acid profiles were investigated using gas chromatography/mass spectrometry followed by ROC (receiver operating characteristics) curves analysis to gain information about biomarkers. Sialic acid (SA) and cytokeratins were measured by the thiobarbituric acid and immunoradiometric methods respectively. Useful fatty acid markers were as follows: erythrocytes, 22:0 and linoleic acid (LA, 18:2n6); platelets, 16:0, 18:0, and LA. At the cutoff value to obtain maximum accuracy, the best biomarker was platelet LA, with higher diagnostic yields than the commonly used markers SA or cytokeratins (100%, 76%, 75% and 86% sensitivity, specificity, positive predictive value and accuracy, respectively). These findings suggest that platelet LA might be used as a biomarker of NSCLC in relation to different aspects of the disease process that now needs to be explored.

Topics: Aged; Biomarkers, Tumor; Blood Platelets; Carcinoma, Non-Small-Cell Lung; Erythrocytes; Female; Humans; Linoleic Acid; Lung Neoplasms; Male; Middle Aged

15-LOX-1 and its metabolites are involved in colorectal cancer. Recently, we reported that 15-LOX-1 overexpression in HCT-116 human colorectal cancer cells inhibited cell growth by induction of p53 phosphorylation (4). To determine whether the 15-LOX-1 protein or its metabolites are responsible for phosphorylation of p53 in HCT-116 cells, we used HCT-116 cells that expressed a mutant 15-LOX-1. The mutant 15-LOX-1 enzyme, with a substitution of Leu at residue His361, was devoid of enzymatic activity. HCT-116 cells transiently transfected with either native or mutant 15-LOX-1 showed an increase in p53 phosphorylation and an increase in the expression of downstream genes. Thus, 15-LOX-1 induces p53 phosphorylation independent of enzymatic activity. Treatment of A549 human lung carcinoma cells with IL-4 increased the expression of 15-LOX-1 and also increased the expression of downstream targets of p53. This confirmed that the activation of p53 was also observed in wild-type cells expressing physiological 15-LOX-1. Immunoprecipitation experiments revealed that 15-LOX-1 interacts with, and binds to, DNA-dependent protein kinase (DNA-PK). The binding of 15-LOX-1 to DNA-PK caused an approximate 3.0-fold enhancement in kinase activity, resulting in increased p53 phosphorylation at Ser15. Knockdown of DNA-PK by small interfering RNA (siRNA) significantly reduced p53 phosphorylation. Furthermore, confocal microscopy demonstrated a colocalization of 15-LOX and DNA-PK in the cells. We propose that the 15-LOX-1 protein binds to DNA-PK, increasing its kinase activity and results in downstream activation of the tumor suppressor p53, thus revealing a new mechanism by which lipoxygenases (LOX) may influence the phenotype of tumor cells.

Topics: Arachidonate 15-Lipoxygenase; Blotting, Western; Colorectal Neoplasms; DNA; Fluorescent Antibody Technique; Gene Expression Regulation, Neoplastic; HCT116 Cells; Humans; Immunoprecipitation; Linoleic Acid; Lung Neoplasms; Phenotype; Phosphorylation; Protein Kinases; RNA, Small Interfering; Transfection; Tumor Suppressor Protein p53

Recent studies have linked conjugated linoleic acid (CLA) to altered tumorigenesis of several sites. We showed recently that a mixture of CLA isomers was able to significantly decrease mammary tumor metastasis in mice. That effect was seen with as little as 0.1% CLA in the diet. Other studies with dietary CLA have shown that various isomers may have differential effects. The purpose of this work was to assess which individual CLA isomers had similar effects in alteration of mouse mammary tumor metastasis. For that, we fed six 20% (w/w) total fat diets which contained either no CLA, low (0.1%, w/w) or high (0.25%, w/w) levels of cis9,trans11-CLA (c9,t11), trans10,cis12-CLA (t10,c12) or a mixture of the 2 isomers (0.125% of each, w/w) as free fatty acids. Neither the separate isomers nor the mixture had an effect on the latency or growth of primary line 4526 tumors when compared to the group without CLA. However, all diets containing CLA significantly decreased the total tumor burden (volume of tumor, mm(3)) in lungs of mice from both spontaneous metastasis (reduced by 42-73%) as well as implantation and survival of the metastatic cell (reduced by 46-61%) when compared with diets containing no CLA. Diets containing a greater concentration of either c9,t11 or t10,c12 had a significantly greater effect compared to the lower concentrations of the respective isomers when metastatic nodule size and total tumor burden were assessed. The diet containing both isomers decreased total tumor burden similarly to the diets containing the lower concentration of each of the isomers. Thus, the effects of c9,t11 and t10,c12 may not be additive and possibly share similar mechanisms for decreasing metastatic tumor burden in mice transplanted with mammary tumor cells.

Topics: Animals; Female; Linoleic Acid; Lung Neoplasms; Mammary Neoplasms, Animal; Mice; Mice, Inbred BALB C; Neoplasm Metastasis; Neoplasm Transplantation; Protein Isoforms

It is well known that simvastatin affects cholesterol synthesis. Furthermore it inhibits growth and proliferation and perturbs fatty acid metabolism in some cell lines. We have studied the effects of simvastatin on the uptake and metabolism of exogenous fatty acid in the human lung adenocarcinoma A549 cells. Simvastatin inhibited the proliferation of A549, and caused an increment in phospholipid/cholesterol ratio due to an increment in phospholipid content without affecting cholesterol content. All the fatty acids were uptaken and metabolized in both control and treated cells. The conversion of palmitic, linoleic and dihomo-gamma-linoleic acids to their metabolites and products/precursor ratios for the desaturation and elongation reactions showed that simvastatin enhanced the Delta5 desaturation step and altered some elongating steps. The machinery for unsaturated fatty acid synthesis in A549 is quite sensitive to simvastatin and its effects could have important implication taking into account that highly unsaturated fatty acids are involved in the regulation of diverse cellular functions by themselves or through their metabolites.

Topics: Adenocarcinoma; alpha-Linolenic Acid; Anticholesteremic Agents; Cell Line; Cholesterol; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Linoleic Acid; Lung Neoplasms; Palmitic Acid; Phospholipids; Simvastatin

I examined the effects of carp oil, oleic acid, linoleic acid and linolenic acid on tumor growth and metastasis to the liver in mice implanted intrasplenically with highly metastatic Lewis lung carcinoma (LLC) tumors. Carp oil (0.1 or 0.2 mL per mouse) significantly reduced tumor growth and metastasis to the liver. Carp oil at 100 or 1000 mg/L inhibited the DNA synthesis in LLC cells, the capillary-like tube formation of human dermal microvascular endothelial cells (HMVEC) at 1000 mg/L and the adherence of LLC cells to HMVEC at 10 to 1000 mg/L (in vitro). Carp oil (0.2 mL per mouse) inhibited the angiogenesis induced by Matrigel supplemented with vascular endothelial growth factor (VEGF) and heparin (in vivo). Antitumor and antimetastatic actions of carp oil might be partly attributable to the inhibition of DNA synthesis in LLC cells and angiogenesis through the inhibition of the adherence of LLC cells to the microvascular endothelium. Oleic acid (0.1 or 0.2 mL per mouse) significantly inhibited the metastasis to the liver, but it had no effect on the primary solid-tumor growth. Oleic acid inhibited the angiogenesis in both in vitro and in vivo models. Oleic acid at 1000 micromol/L inhibited the DNA synthesis in LLC cells but did not affect the DNA synthesis in HMVEC. These inhibitory actions of oleic acid may be attributable to the inhibition of angiogenesis induced by the tumor. Linoleic acid and linolenic acid had no effect on tumor growth or metastasis to the liver.

Topics: alpha-Linolenic Acid; Animals; Biocompatible Materials; Blood Cell Count; Body Weight; Carcinoma, Lewis Lung; Carps; Collagen; DNA; Drug Combinations; Energy Intake; Fish Oils; Humans; Laminin; Linoleic Acid; Lung Neoplasms; Mice; Mice, Inbred C57BL; Neoplasm Metastasis; Neovascularization, Pathologic; Oleic Acid; Organ Size; Proteoglycans; Tumor Cells, Cultured

Recent studies have shown that conjugated linoleic acid (CLA) can inhibit the initiation and thus, incidence of mammary tumors in rodents. The concentration of CLA required for these effects was as low as 0.1% of the diet, with no increased effects above 1%. To date, there is little evidence that CLA has any effect on growth or metastasis of mammary tumors. In this report, we demonstrate that CLA, at the concentrations used in previous studies, had a significant effect on the latency, metastasis, and pulmonary tumor burden of transplantable murine mammary tumors grown in mice fed 20% fat diets. The latency of tumors from mice fed CLA was significantly increased when compared with the 0% CLA control diet. The volume of pulmonary tumor burden, as a result of spontaneous metastasis, decreased proportionately with increasing concentrations of dietary CLA. With 0.5 and 1% CLA, pulmonary tumor burden was significantly decreased compared to mice treated with the eicosanoid inhibitor, indomethacin and fed diets containing no CLA. Tumors of mice fed as little as 0.1% CLA and as much as 1% had significantly decreased numbers of pulmonary nodules when compared with diets containing no CLA. The decrease in the number of pulmonary nodules by CLA was nearly as effective as indomethacin, a known suppressor of tumor growth and metastasis in this malignant model. These data suggest that effects of CLA on mammary tumorigenesis may go beyond the reported alterations in tumor incidence and effect later stages, especially metastasis.

Topics: Animals; Dietary Fats, Unsaturated; Dose-Response Relationship, Drug; Female; Linoleic Acid; Lung Neoplasms; Mammary Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Neoplasm Metastasis; Time Factors; Tumor Cells, Cultured

The effects of absorption enhancers on the pulmonary absorption of (Asu1,7)-eel calcitonin (ECT) and their pulmonary toxicity were examined by means of in situ pulmonary experiments. The absorption of ECT from the lungs was estimated by its hypocalcemic effect. The pulmonary membrane toxicity of absorption enhancers was evaluated by the leakage of Evans Blue from the plasma into the lungs. In the absence of absorption enhancers, a slight hypocalcemic effect was obtained following intrapulmonary administration of ECT. However, we found significant hypocalcemic effects after the ECT administration with 10 mM n-lauryl beta-D-maltopyranoside (LM), 10 mM sodium glycocholate (NaGC), and 10 mM linoleic acid-HCO60 (hydrogenated caster oil) mixed micelle (MM). The plasma calcium levels decreased as the amount of LM coadministered with ECT increased. In contrast, 10 mM EDTA did not improve the pulmonary absorption of ECT. Overall, a correlation between the pulmonary absorption of ECT and local toxicity was observed in the presence of these additives. However, 1 mM LM, 10 mM NaGC, and 10 mM MM improve the pulmonary absorption of ECT with low pulmonary toxicity. These findings suggest that the use of these adjuvants would be a useful approach for improving the pulmonary absorption of ECT.

Topics: Absorption; Animals; Calcitonin; Calcium; Castor Oil; Glycocholic Acid; Linoleic Acid; Lung; Lung Neoplasms; Male; Maltose; Micelles; Rats; Rats, Wistar; Surface-Active Agents

Growth and metastasis to the lung of the human breast cancer cell line MDA-MB-435 in nude mice fed a high-fat (20% wt/wt) high-linoleic acid (LA; 12% wt/wt) diet were significantly reduced by the addition of the cyclooxygenase inhibitor indomethacin to the drinking water at a dose of 10 micrograms/ml (approximately 1 mg/kg body wt). No toxicity was observed in these mice; at 20 micrograms/ml indomethacin, gastric ulcerations occurred. After necropsy, tumor eicosanoids were measured by radioimmunoassay in the control and 10 micrograms/ml indomethacin treatment groups. Levels of the cyclooxygenase products prostaglandin (PG) E (PGE), 6-keto-PGF1 alpha, and thromboxane B2 (TxB2) were significantly reduced in indomethacin-treated mice compared with controls; however, the 6-keto-PGF1 alpha-to-TxB2 ratio was significantly increased. Two lipoxygenase products, 5-hydroxyeicosatetraenoic acid (5-HETE) and 15-HETE, were unaffected, but the 12-HETE levels were increased compared with the untreated high-LA-fed group. Metastases to the lungs in mice fed a high-fat low-LA (2% wt/wt) diet were also reduced compared with those in the high-LA-fed control mice, but whereas tumor cyclooxygenase and lipoxygenase product levels were reduced, no change in the 6-keto-PGF1 alpha-to-TxB2 ratio was observed. The use of selective cyclooxygenase inhibitors may prevent LA-mediated progression of breast cancer at several levels of the metastatic cascade, among which may be interference with tumor cell-vascular endothelial cell interaction and with angiogenesis.

Topics: Animals; Breast Neoplasms; Cell Division; Cyclooxygenase Inhibitors; Dietary Fats; Eicosanoids; Female; Humans; Indomethacin; Linoleic Acid; Linoleic Acids; Lung Neoplasms; Mice; Mice, Nude; Neoplasm Metastasis; Neoplasm Transplantation; Tumor Cells, Cultured

It has been reported that gamma-linolenic acid (GLA)-rich diets suppress mammary carcinogenesis and transplanted tumor growth and that GLA inhibits the growth of cultured human cancer cell lines. We compared the effects of dietary GLA and linoleic acid (LA) on the growth of MDA-MB-435 human breast cancer cells and their expression of the metastatic phenotype in vivo and in vitro. Athymic nude mice (30/dietary group) were fed isocaloric diets containing 20% (wt/wt) fat but providing 8% GLA or LA for 7 days, and 10(6) tumor cells were then injected into a thoracic mammary fat pad. The diets were continued for a further 11 weeks. The primary tumor growth rates were similar in mice from the two dietary groups; there was a nonstatistically significant trend for the incidence of macroscopic lung metastases and the total lung metastatic volumes to be higher in the GLA-fed mice (79% and 40.1 +/- 13.9 mm3) than in the LA-fed mice (64% and 15.5 +/- 5.4 mm3). The tumor cell phospholipids from the 8% GLA-fed mice contained significantly lower LA levels but higher arachidonic acid levels (both p < 0.001) than those from 8% LA-fed mice. Also the arachidonate-derived eicosanoids (prostaglandin E, leukotriene B4, and 5-, 12-, and 15-hydroxyeicosatetraenoic acids) were significantly higher in tumors from the 8% GLA group. Zymography showed higher 92-kDa type IV collagenase activity in tumors from 8% GLA-fed mice. In vitro, GLA and LA, at 0.5-2 micrograms/ml, stimulated MDA-MB-435 cell growth; 10 micrograms/ml was mildly inhibitory. Whereas LA stimulated tumor cell invasion and 92-kDa type IV collagenase production in vitro, GLA inhibited invasion and did not induce activity of the proteolytic enzyme. Our results do not support the hypothesis that supplementation with GLA would exert a beneficial effect on the progression of an existing breast cancer, perhaps because it is metabolized in vivo to arachidonate-derived eicosanoids that are known to be involved in the metastatic process.

Topics: Animals; Arachidonic Acid; Body Weight; Breast Neoplasms; Cell Division; Collagenases; Dietary Fats; Eicosanoids; Fatty Acids; Female; gamma-Linolenic Acid; Humans; Linoleic Acid; Linoleic Acids; Lung Neoplasms; Mice; Mice, Nude; Neoplasm Invasiveness; Phospholipids; Tumor Cells, Cultured

In order to investigate the possible mechanisms underlying platelet functional changes in patients affected by neoplasms, platelet lipid composition, plasma beta-thromboglobulin (Beta-TG) and serum thromboxane B2 (TXB2) were investigated in 16 male patients affected by pulmonary carcinoma and in 16 comparable control subjects. In patients high levels of plasma Beta-TG (67 +/- 9 versus controls 14 +/- 4 ng/ml, p < 0.001) and serum TXB2 (434 +/- 56 versus 223 +/- 48 ng/ml, p < 0.001) were observed. Also platelet lipid composition was found altered in patients with respect to controls (lower percent levels in n-3 fatty acids and in linoleic acid esterified in the main platelet phospholipid fractions: at least p < 0.05). These results indicate that in vivo platelet activation is detectable in neoplastic patients and it is associated with alterations in platelet lipid composition. In the light of the important role played by membrane lipids in platelet functions related to thrombosis and haemostasis we conclude that platelet lipid changes could cooperate in platelet activation and increased thrombotic risk so frequently observed in neoplastic disease.

Topics: Adult; beta-Thromboglobulin; Blood Platelets; Carcinoma, Squamous Cell; Docosahexaenoic Acids; Eicosapentaenoic Acid; Humans; Linoleic Acid; Linoleic Acids; Lipids; Lung Neoplasms; Male; Platelet Activation; Platelet Factor 4; Thromboxane B2

The purpose of the study was to compare the effects of dietary linoleic acid (LA) intake on the growth and metastasis of MDA-MB-435 and MDA-MB-231 human breast cancer cells in nude mice, together with their invasive capacity and secretion of type IV collagenase (gelatinase) in vitro. Each tumor cell line (10(6) cells) was injected into a right-sided mammary fat pad in 60 mice with equal numbers (30 mice/group) assigned to isocaloric diets containing 23% (w/w) total fat and 2% or 12% (w/w) LA. The MDA-MB-435-cell mammary fat pad tumors became palpable earlier and initially they grew more rapidly, but by 6 weeks the MDA-MB-231-cell tumors exhibited an acceleration of growth which was enhanced by the high-LA diet. At necropsy, 12 weeks after the tumor cell injections, the mean weight [10.2 +/- 1.4 g(SEM)] of mammary fat pad MDA-MB-231 cell tumors in 12% LA-fed mice was significantly higher (6.7 +/- 1.4 g) than that of the mice fed 2% LA; also, it was higher than that of MDA-MB-435 cell tumors in the 12% LA-fed mice (3.6 +/- 0.1 g) or the 2% LA-fed mice (3.3 +/- 0.1 g) (each P < 0.001). Mice fed the 12% LA diet had a higher incidence of grossly visible MDA-MB-435 cell pulmonary metastatic nodules than those fed the 2% LA diet (67% versus 33%; P < 0.02), more metastatic lesions (5.7 +/- 1.6 versus 2.3 +/- 0.8; P < 0.05), and greater total volumes (62.0 +/- 25.9 versus 24.8 +/- 9.0 mm3; P < 0.02) per mouse. Of the MDA-MB-231 cell tumor-bearing mice, only 1 in the 12% LA dietary group and 2 in the 2% LA dietary group had macroscopic nodules but the incidence of microscopic metastases was 68 and 42%, respectively. The MDA-MB-231 cell line exhibited a relatively high capacity for invasion in vitro and constitutively high levels of both total type IV collagenolytic activity and M(r) 92,000 gelatinase production which were unaffected by LA. In contrast, MDA-MB-435 cells had approximately only one-sixth the invasive capacity and secreted a relatively low level of type IV collagenase and little of the M(r) 92,000 gelatinase; both invasion and enzyme production were stimulated by LA.

Topics: Animals; Breast Neoplasms; Cell Division; Collagenases; Female; Humans; Linoleic Acid; Linoleic Acids; Lung Neoplasms; Matrix Metalloproteinase 9; Mice; Mice, Nude; Neoplasm Invasiveness; Random Allocation; Tumor Cells, Cultured

The purpose of the study was to determine the effect of three different levels of dietary linoleic acid (LA) intake on the growth of MDA-MB-435 human breast cancer cells in the mammary fat pads of nude mice, and their metastasis to the lungs. These diets were isocaloric, and contained different mixtures of safflower (LA-rich) and coconut (saturated fatty acid-rich) oils to provide 23% (w/w) total fat, with 2, 8, and 12% (w/w) LA. A fourth group was fed a low-fat, 5% (w/w) corn oil diet. There were 25 mice in each dietary group. A necropsy, 12 weeks after the tumor cell injections, the primary tumor weights in the 12% LA (4.1 +/- 2.7 g)- and 8% LA (3.5 +/- 1.7 g)-fed groups were significantly greater (P < 0.05) than those fed the 2% LA diet (2.5 +/- 1.5 g); they did not differ significantly from the weights of mammary fat pad tumors in the 5% corn oil-fed mice. The incidence of grossly visible pulmonary metastatic nodules was not significantly different between the 8 and 12% LA-fed mice, but was higher for both groups compared with the 2% LA-fed group (P < 0.05), with a similar trend in comparison with the 5% corn oil group. The mean total calculated volumes of the macroscopic metastases per tumor-bearing mouse were significantly greater in the 8 and 12% LA (157 +/- 250.7 and 99.1 +/- 140.0 mm3, respectively), compared with the 2% LA (23.3 +/- 51.8 mm3)- and 5% corn oil (24.5 +/- 35.1 mm3)-fed mice; all P < 0.05. Micrometastases were observed most frequently in the 5% corn oil and 2% LA dietary groups, but none of the differences were statistically significant. No differences were detected in the concentrations of prostaglandin E, leukotriene B4, or 5-hydroxyeicosatetraenoic acid in tumors from mice fed the four different diets.

Topics: Adipose Tissue; Animals; Breast Neoplasms; Cell Division; Dietary Fats; Female; Humans; Linoleic Acid; Linoleic Acids; Lung Neoplasms; Mammary Glands, Animal; Mice; Mice, Nude; Neoplasm Metastasis; Transplantation, Heterologous; Tumor Cells, Cultured

Results from epidemiological studies have generally indicated an association of dietary saturated animal fats with human breast cancer risk. Some studies, however, have suggested a similar association for some polyunsaturated vegetable fats shown to promote both rodent mammary carcinogenesis and metastasis. This study was performed to evaluate the effects of corn oil on growth and metastasis of MDA-MB-435 human breast cancer cells, which have a propensity for metastasis. Corn oil is rich in the omega-6 fatty acid linoleic acid. Fifty-eight female athymic nude mice (NCr-nu/nu) were fed a high-fat diet (23% wt/wt corn oil; 12% linoleic acid) or a low-fat diet (5% wt/wt corn oil; 2.7% linoleic acid). Seven days after diets were started, tumor cells (1 x 10(6) were injected into a mammary fat pad. The time to appearance of solid tumors and the tumor size were recorded. After 15 weeks, the study was terminated, and autopsies were performed to determine the weight of the primary tumor and the extent of metastasis. The latent interval for tumor appearance in the animals fed the high-fat diet was shorter than that in the low-fat diet group, and the tumor growth rate in the high-fat diet group showed a small but statistically significant increase compared with the low-fat diet group. Primary tumors developed in 27 of the 29 mice on the high-fat diet and in 21 of the 29 on the low-fat diet. Of the mice with palpable primary tumors, 18 of 27 in the high-fat diet group and eight of 21 in the low-fat diet group had macroscopic lung metastases. The extent of metastasis in the high-fat diet group was independent of the primary tumor weight, but only those in the low-fat diet group with primary tumors weighing more than 2 g developed metastases. These results suggest that a high-fat diet rich in omega-6 polyunsaturated fatty acid can enhance metastasis of human breast cancer cells in this mouse model. The findings support the need for further study of the relationship between dietary polyunsaturated fats and breast cancer risk and for experiments to determine the effect on metastasis of only a 50% difference in fat intake--the dietary goal of the proposed clinical trials of low-fat dietary intervention in breast cancer patients.

Topics: Animals; Breast Neoplasms; Chi-Square Distribution; Corn Oil; Dietary Fats; Female; Humans; Linoleic Acid; Linoleic Acids; Lung Neoplasms; Mammary Neoplasms, Experimental; Mice; Mice, Nude; Tumor Cells, Cultured

We have previously shown that a high fat diet (20% w/w) containing 12% linoleic acid (18:2) can significantly increase the metastasis of mammary tumor cells when compared with high fat diets that contain 8% or less 18:2 with a constant level of oleic acid (18:1). This effect may have been due to an alteration of eicosanoid metabolism because the cyclooxygenase inhibitor, indomethacin, abolished the increase. Because 18:1 may interfere with the metabolism of 18:2 to 20:4, we have now tested whether the 18:1 that supplements the 18:2 diet can have an effect on spontaneous or experimental metastasis of the line 4526 murine mammary tumor. For this, six 20% fat diets were formulated with 1%, 6%, and 12% 18:2 and either high or low levels of 18:1. Our results indicate that the amount of select fatty acids other than 18:2 at 12% has no significant effect on mouse growth, tumor growth, or tumor latency. When spontaneous metastatic burden was calculated, no significant differences between mice fed diets containing 1% and 6% 18:2 were observed. However, 4 to 5 times more of a metastatic burden was observed in mice fed diets containing 12% 18:2. No significant differences were observed between high and low 18:1 diets when the 18:2 content was 1 or 12%. However, at 6% 18:2, 18:1 significantly decreased metastatic burden. When experimental metastasis was assessed, relatively low levels of surface lung nodules were observed at 1% and 6% 18:2, but significantly higher levels were observed at 12% 18:2.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Dietary Fats; Fatty Acids; Female; Linoleic Acid; Linoleic Acids; Lung Neoplasms; Mammary Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Neoplasm Metastasis; Oleic Acid; Oleic Acids

Improved serum-free media were developed for the anchorage-dependent growth of A549 human lung carcinoma and B16 mouse melanoma cell lines in vitro. Type 1 transforming growth factor beta (TGF-beta 1) inhibited the growth of A549 or B16 cells under serum-free conditions or in the presence of 10% serum by 15-33%. In contrast, in the presence of micrograms/ml concentrations of polyunsaturated fatty acids (PUFAs), picomolar concentrations of TGF-beta 1 irreversibly inhibited the serum-free growth of A549 or B16 cells by 90-100%. The PUFAs alone had little effect on cell growth. Cell growth inhibition by TGF-beta 1 was not potentiated by saturated fatty acids, monounsaturated fatty acids, or prostaglandins. Inhibition of A549 or B16 cell growth by TGF-beta 1 in the presence of PUFAs was almost completely reversed by the antioxidant vitamin E, suggesting a role for lipid peroxidation in this process. Inhibition of A549 or B16 cell growth by TGF-beta 1 in the presence of 5% fetal calf serum was also potentiated by PUFAs and partially reversed by antioxidants. The presence of retinoic acid was required for maximal PUFA-dependent growth inhibition of A549 or B16 cells by TGF-beta 1 under some, but not all, conditions. These results suggest that inhibition of carcinoma and melanoma cell growth by TGF-beta 1 is mediated, in large part, by PUFAs.

Topics: Animals; Carcinoma; Cell Division; Cell Line; Dose-Response Relationship, Drug; Fatty Acids, Monounsaturated; Fatty Acids, Unsaturated; Humans; Kinetics; Linoleic Acid; Linoleic Acids; Lung Neoplasms; Melanoma, Experimental; Mice; Palmitic Acids; Stearic Acids; Transforming Growth Factors; Tumor Cells, Cultured; Vitamins

Lewis lung carcinoma cells express a plasma membrane receptor (i.e., IRGpIIb/IIIa) which is immunologically and functionally related to the platelet aggregation receptor complex (i.e., GpIIb/IIIa). Both fluorescence microscopy and flow cytometric analysis reveal that surface expression and/or activation of this tumor cell receptor is enhanced by a phorbol ester [i.e., 12-O-tetradecanoylphorbol-13-acetate (TPA)] and a lipoxygenase metabolite of arachidonic acid; 12-hydroxyeicosatetraenoic acid (i.e., 12-HETE). TPA-enhanced expression appears to be mediated by a lipoxygenase metabolite, as this effect can be reversed by lipoxygenase inhibitors but not by cyclooxygenase inhibitors. In parallel with these results both TPA and 12(S)-HETE [but not 12(R)-HETE] enhance tumor cell adhesion to endothelial cells, subendothelial matrix and fibronectin, but not to type IV collagen. TPA-enhanced adhesion can be reduced by lipoxygenase inhibitors but not by cyclooxygenase inhibitors and in addition, stimulated adhesion can be blocked by pretreatment of tumor cells with specific polyclonal or monoclonal antibodies which react against IRGpIIb/IIIa. 12(S)-HETE-enhanced adhesion can also be inhibited by these same antibodies. In contrast, a lipoxygenase product of linoleic acid, 13(S)-hydroxyoctadecadienoic acid, inhibited TPA and 12(S)-HETE-enhanced tumor cell adhesion to endothelial cells, subendothelial matrix, and fibronectin. These results suggest that (a) IRGpIIb/IIIa is a multifunctional receptor which mediates tumor cell adhesion to a variety of biological substrata, (b) TPA enhances surface expression and/or activation of this receptor possibly via a lipoxygenase metabolite of arachidonic acid, and (c) these effects are opposed by a lipoxygenase metabolite of linoleic acid.

Topics: 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; Animals; Antibodies; Antibodies, Monoclonal; Antigen-Antibody Complex; Arachidonic Acids; Cell Adhesion; Cell Membrane; Collagen; Endothelium, Vascular; Flow Cytometry; Fluorescent Antibody Technique; Hydroxyeicosatetraenoic Acids; Isomerism; Linoleic Acid; Linoleic Acids; Lipoxygenase; Lung Neoplasms; Male; Mice; Mice, Inbred C57BL; Platelet Membrane Glycoproteins; Rats; Rats, Inbred Strains; Tetradecanoylphorbol Acetate

Linoleic acid, an omega-6 unsaturated fatty acid, stimulated growth of the MDA-MB-231 and MCF-7 human breast cancer cell lines in culture. Responses of the estrogen-independent MDA-MB-231 cells both in serum-free medium and with 1% fetal bovine serum added were positively correlated with linoleic acid concentration over the entire range examined (5-750 ng/ml). Growth stimulation of the estrogen-responsive MCF-7 cell line was maximal at a LA concentration of 500 ng/ml when cultured in 1% fetal bovine serum-containing medium with added estradiol. Linoleic acid had no mitogenic effect on three human cancer cell lines derived from sites other than breast, or on untransformed 3T3 cells.

Topics: Breast Neoplasms; Carcinogens; Dietary Fats; Humans; Linoleic Acid; Linoleic Acids; Lung Neoplasms; Male; Prostatic Neoplasms; Skin Neoplasms; Tumor Cells, Cultured

High levels of dietary linoleic acid (18:2) have been shown to increase the spontaneous metastasis of line 4526 mouse mammary tumors. In this report, the influence of 18:2 on specific events of tumor metastasis, namely, lodgement, proliferation and survival, were studied using spontaneous and experimental metastasis assays with line 4526 cells. A significantly greater number of radiolabeled tumor cells lodged in the lungs of mice fed 4, 8 and 12% 18:2 when compared with mice fed lower levels of 18:2. The effect of dietary 18:2 appeared to be on the host tissue (lungs) and not the tumor cells. Lodgement of tumor cells first cultured in serum of mice fed 18:2 then injected into mice fed 1% 18:2 was not affected. There were no significant differences in the percentage of [3H]thymidine labeled metastatic cells from lungs of mice fed different levels of 18:2. However, the number of surface lung nodules that appeared in mice 21 days after injection of unlabeled line 4526 cells increased in mice fed 8 and 12% 18:2 compared with those fed lower levels of 18:2. Thus, dietary 18:2 may increase metastasis by influencing the lodgement, implantation and survival but not proliferation of line 4526 mouse mammary tumor cells.

Topics: Animals; Cell Adhesion; Cell Division; Cell Line; Cell Survival; Dietary Fats; Female; Linoleic Acid; Linoleic Acids; Lung Neoplasms; Mammary Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Neoplasm Metastasis; Neoplasm Transplantation

The influence of quantitative differences in dietary linoleic acid (18:2) on the metastasis as well as the development of line 4526 mouse mammary tumors was investigated. High fat diets (20%, w/w) that contained either 1, 2, 4, 8, or 12% 18:2 by weight, were prepared by using mixtures of coconut and safflower oil and fed to female BALB/c mice that were subsequently inoculated with 10(4) 4526 tumor cells s.c., either at the lateral abdominal wall (LAW) or in the mammary fat pad (MFP). Latency of LAW tumors was influenced by the level of dietary 18:2, whereas the latency of MFP tumors was not. When metastasis was assessed, mice with MFP tumors fed 1, 2, 4, or 8% 18:2 diets had 62-73% fewer lung surface tumor nodules than similar mice fed 12% 18:2. Mice in all dietary groups with LAW tumors had fewer metastatic lung nodules than mice with MFP tumors; mice with LAW tumors fed diets containing 1, 2, or 4% 18:2 had 52-69% fewer nodules than similar mice fed diets containing 8 or 12% 18:2. There were no significant differences in the rate of increase of body weight or the daily mean tumor volumes when compared with dietary 18:2 level. Fatty acid composition of the tumor, particularly the level of 18:2, was significantly altered by diet. This study demonstrates that while the level of dietary 18:2 does not enhance the growth rate of primary 4526 tumors and does or does not affect the latency depending on the primary site, it does significantly alter the metastasis. These results stress the importance of metastasis assessment in future studies involving dietary fat effects on tumorigenesis.

Topics: Animals; Body Weight; Dietary Fats; Fatty Acids; Female; Linoleic Acid; Linoleic Acids; Lung Neoplasms; Mammary Neoplasms, Experimental; Mice; Mice, Inbred BALB C; Neoplasm Metastasis; Neoplasm Transplantation