Plasma lipids and prolactin in patients with breast cancer

Serum Prolactin Levels as a Novel, Practical Marker for Predicting Malignant Diseases of the Breast

Background and objective Prolactin (PRL) has a high specificity toward breast cancer (BC), making it a valuable marker in both diagnosis and prognosis. In this study, we aimed to compare serum PRL levels between pre- and post-menopausal women with BC, as well as normal reference values. We also investigated the association of various risk factors with PRL levels in women with BC. Methods The study involved adult women diagnosed with BC based on clinical features and tissue histopathology receiving treatment at a tertiary care center in Pune, India. General and demographic information, anthropometric measurements (height, weight, and BMI), menstrual status (age at menarche and menopausal state), clinical presentation (signs and symptoms), duration of symptoms, and parity were recorded by using a pre-tested proforma based on hospital records or in-person interviews. Serum PRL was measured by the RIA method (sandwich assay). Results A total of 67 women (average age: 47.5 ± 11.8 years; 33 of them post-menopausal) with BC were included in the study. The participants had an average BMI of 24.9 ± 3.5 kg/m2, and 26 (39%) of them were overweight. The majority of women had BC stage IIA disease, involvement of the right side or upper outer quadrant, and had attained menarche after 14 years of age; 47 women had a BC duration of >3 months. Seven women were nulliparous, and the remaining had given birth to their first child before the age of 26 years. The average serum PRL level among the participants was 9.27 ± 7.62 ng/mL, with higher levels found in post-menopausal women compared to pre-menopausal women (11.08 vs. 7.51 ng/mL, respectively; p=0.08). Women with a higher stage and greater duration of disease had significantly higher serum PRL levels (p<0.001 for both). When compared with reference values, pre-menopausal women showed significantly lower (6.25 vs. 10.9, respectively; p=0.001) and post-menopausal women showed significantly higher (8.55 vs. 5.95; p=0.004) serum PRL levels. A positive correlation was found between serum PRL and age at the time of birth of the first child (p=0.068). Conclusions Based on our findings, PRL is an important hormone in the development of BC in women. Therapeutic modulation of PRL may be a realistic and novel approach to curing human BC, either administered alone or in combination with conventional treatments.

Anthracycline-induced cardiotoxicity: targeting high-density lipoproteins to limit the damage?

Doxorubicin (DOX) is an anthracycline antibiotic frequently used against a wide range of cancers, including breast cancer. Although the drug is effective as a treatment against cancer, many patients develop heart failure (HF) months to years following their last treatment with DOX. The challenge in preventing DOX-induced cardiotoxicity is that symptoms present after damage has already occurred in the myocardium. Therefore, early biomarkers to assess DOX-induced cardiotoxicity are urgently needed. A better understanding of the mechanisms involved in the toxicity is important as this may facilitate the development of novel early biomarkers or therapeutic approaches. In this review, we discuss the role of high-density lipoprotein (HDL) particles and its components as possible key players in the early development of DOX-induced cardiotoxicity. HDL particles exist in different subclasses which vary in composition and biological functionality. Multiple cardiovascular risk factors are associated with a change in HDL subclasses, resulting in modifications of their composition and physiological functions. There is growing evidence in the literature suggesting that cancer affects HDL subclasses and that healthy HDL particles enriched with sphingosine-1-phosphate (S1P) and apolipoprotein A1 (ApoA1) protect against DOX-induced cardiotoxicity. Here, we therefore discuss associations and relationships between HDL, DOX and cancer and discuss whether assessing HDL subclass/composition/function may be considered as a possible early biomarker to detect DOX-induced cardiotoxicity.

Obesity and Postmenopausal Hormone Receptor-positive Breast Cancer: Epidemiology and Mechanisms

Obesity is a potential risk for several cancers, including postmenopausal, hormone dependent breast cancers. In this review, we summarize recent studies on the impact of obesity on postmenopausal women's health and discuss several mechanisms that were proposed to increase the risk of breast carcinogenesis.

Metabolic syndrome and breast cancer: a dangerous association for postmenopausal women

BACKGROUND

Breast cancer(BC) is the most common cancer in women worldwide, the relationship between metabolic syndrome(MetS) and BC needs to be better clarified. Today the early diagnosis of breast cancer(BC) is yet a challenging problem in clinical practice, so the evidence that a well identified population of postmenopausal women, affected by MetS, presents a high risk, of breast cancer occurrence, is useful for breast cancer prevention. Our study aims to assess the prevalence of metabolic syndrome, diagnosed according to current guidelines, in postmenopausal women with breast cancer, and its role as an independent risk factor.

RESULTS

MetS rate was significantly higher among women affected by BC:10.1%, 33 women, than CG:5.4%, 18 women, Chi-squared4.8,Odds ratio1.94,c.i.95%,p<0.02. Metabolic cardiomyopathy rate was significantly higher among women affected by BC:5.8%, 18 women, than CG:1.8%, 6 women, Chi-squared6.5,Odds ratio3.2,c.i.95%,p<0.01. Otherwise MetS rate without cardiomyopathy was higher among women affected by BC:4.8%, 15 women, than CG:3.4%, 11 women, but in a not statistically significant way, Chi-squared0.8,Odds ratio1.35,c.i.95%,p<0.36.

CONCLUSION

There was a significant relationship, in our population, between MetS and BC, adding evidence to this controversial association, the relationship was even tighter, when restricted to women affected by metabolic cardiomyopathy; otherwise it, restricted to women affected by MetS, without metabolic cardiomyopathy, was not statistically significant. Since the prevalence of MetS is increasing worldwide, just like the incidence of BC, an intervention is needed to improve physical activity and weight reduction to decrease the MetS rate.

Expression of SR-B1 receptor in breast cancer cell lines, MDAMB-468 and MCF-7: Effect on cell proliferation and apoptosis

OBJECTIVES

High-density lipoprotein (HDL) is necessary for proliferation of several cells. The growth of many kinds of cells, such as breast cancer cells (BCC) is motivated by HDL. Cellular uptake of cholesterol from HDL which increases cell growth is facilitated by scavenger receptors of the B class (SR-BI). The proliferative effect of HDL might be mediated by this receptor. It is also believed that HDL has an anti-apoptotic effect on various cell types and promotes cell growth. This study was designed to investigate SR-BI expression, proliferation and apoptotic effect of HDL on human BCC lines, MCF-7 and MDA-MB-468.

MATERIALS AND METHODS

Real-time-PCR method was used to evaluate expression of SR-BI, and cholesterol concentration was measured using a cholesterol assay kits (Pars AZ moon, Karaj, Iran). Cell viability was assessed using the MTT test. To identify cell apoptosis, the annexin V-FITC staining test and caspase-9 activity assay were applied.

RESULTS

Treatment of both cell lines (MCF-7, MDA-MB-468) with HDL results in augmentation of SR-BI mRNA expression and also elevation of the intracellular cholesterol (P<0.01). HDL induced cell proliferation, cell cycle progression, and prevented activation of caspase-9 (P<0.05). We also demonstrated that inhibition of SR-B1 by BLT-1 could reduce cell proliferation, and induction of SR-B1 receptor by quercetin increased HDL-induced proliferation in both cell lines (P<0.05).

CONCLUSION

It can be concluded that alteration in HDL levels by SR-B1 activator (Quercetin) or inhibitor (BLT-1) may affect BCC growth and apoptosis induction.

Proinflammatory circulating markers: new players for evaluating asymptomatic acute cardiovascular toxicity in breast cancer treatment

PURPOSE

This study aimed to evaluate markers of cardiac damage (total CK, CKMB and CRP), inflammatory markers (free iron, homocysteine and TNF-α) as well as lipidogram in breast cancer patients undergoing acute cycles of doxorubicin (DOX), paclitaxel (PTX) or trastuzumab (TZ) and to verify if there is an association between these markers and the toxicity of the chemotherapeutic treatment. Methods: Included in the study were 120 breast cancer patients and 50 healthy controls. All analyzes were performed on automated systems. For the statistical analysis, each group was compared with the controls according to their normality by Student's t-test and Mann-Whitney test. Results: Our results showed that DOX treatment led to increased hsCRP (4.80 ± 1.23 mg/dL, p = 0.0005), triglycerides (187.6 ± 25.06, p = 0.0231), TNF-α (42.31 ± 17.96 pg/mL, p = 0.01) and Fe levels (138.8 ± 18.6 μg/dL, p = 0.0193). In the meantime, PTX induced changes in CK-MB (8.78 ± 4.2 U/L, p = 0.0361), hsCRP (7.12 ± 1.87 mg/dL, p = 0.0006), cholesterol (201.7 ± 19.54, p = 0.05), triglycerides (201.7 ± 19.54, p = 0.0277), TNF-α (38.27 ± 9.12 pg/mL, p = 0.023), homocysteine (10.95 ± 0, 86 μmol/L, p = 0.005), and free iron (113 ± 18 6 μg/dL, p = 0.045) while TZ augmented CK-MB (6.9 ± 1.97 U/L, p < 0.00), hsPCR (3.12 ± 0.68 mg/dL, p = 0.095), cholesterol (218.3 ± 16.79, p = 0.0317), triglycerides (218.3 ± 16.79, p = 0.0127), TNF-α (89.6 ± 12.11, p = 0.032), homocysteine (9.95 ± 1.15 μmol/L, p = 0.0396), free iron (120.5 ± 4.64 μg/dl, p = 0.0058) as well. Conclusions: Our data demonstrated the existence of a proinflammatory net triggered by breast cancer chemotherapy that could increase cardiomyocytes permeability and allow the leakage of circulating proteins as CK-MB and induce the production of hsCRP.

Metabolic syndrome and breast cancer: a dangerous association for postmenopausal women

BACKGROUND

Breast cancer(BC) is the most common cancer in women worldwide, the relationship between metabolic syndrome(MetS) and BC needs to be better clarified. Today the early diagnosis of breast cancer(BC) is yet a challenging problem in clinical practice, so the evidence that a well identified population of postmenopausal women, affected by MetS, presents a high risk, of breast cancer occurrence, is useful for breast cancer prevention. Our study aims to assess the prevalence of metabolic syndrome, diagnosed according to current guidelines, in postmenopausal women with breast cancer, and its role as an independent risk factor.

RESULTS

MetS rate was significantly higher among women affected by BC:10.1%, 33 women, than CG:5.4%, 18 women, Chi-squared4.8,Odds ratio1.94,c.i.95%,p<0.02. Metabolic cardiomyopathy rate was significantly higher among women affected by BC:5.8%, 18 women, than CG:1.8%, 6 women, Chi-squared6.5,Odds ratio3.2,c.i.95%,p<0.01. Otherwise MetS rate without cardiomyopathy was higher among women affected by BC:4.8%, 15 women, than CG:3.4%, 11 women, but in a not statistically significant way, Chi-squared0.8,Odds ratio1.35,c.i.95%,p<0.36.

CONCLUSION

There was a significant relationship, in our population, between MetS and BC, adding evidence to this controversial association, the relationship was even tighter, when restricted to women affected by metabolic cardiomyopathy; otherwise it, restricted to women affected by MetS, without metabolic cardiomyopathy, was not statistically significant. Since the prevalence of MetS is increasing worldwide, just like the incidence of BC, an intervention is needed to improve physical activity and weight reduction to decrease the MetS rate.

Lipoprotein Drug Delivery Vehicles for Cancer: Rationale and Reason

Lipoproteins are a family of naturally occurring macromolecular complexes consisting amphiphilic apoproteins, phospholipids, and neutral lipids. The physiological role of mammalian plasma lipoproteins is to transport their apolar cargo (primarily cholesterol and triglyceride) to their respective destinations through a highly organized ligand-receptor recognition system. Current day synthetic nanoparticle delivery systems attempt to accomplish this task; however, many only manage to achieve limited results. In recent years, many research labs have employed the use of lipoprotein or lipoprotein-like carriers to transport imaging agents or drugs to tumors. The purpose of this review is to highlight the pharmacologic, clinical, and molecular evidence for utilizing lipoprotein-based formulations and discuss their scientific rationale. To accomplish this task, evidence of dynamic drug interactions with circulating plasma lipoproteins are presented. This is followed by epidemiologic and molecular data describing the association between cholesterol and cancer.

Serum Lipid Profile and Its Relationship with Host Immunity in Carcinomas of the Breast and Uterine Cervix

Carcinomas of the uterine cervix and breast, which have a different etiopathogenesis, are the most common malignancies among Indian women. Between these two cancers a comparative study was undertaken in which serum lipids were assessed along with host immunity. Thirty randomly selected cases each of breast and cervical carcinoma, and 20 matched healthy control women were studied by means of standard procedures. Significantly higher (P < 0.001) mean levels of triglycerides (x = 192.1 mg/dl, SD ± 113.5) and total cholesterol (x = 212.9 mg/dl, SD ± 49.78) were observed in breast cancer as compared to controls or cervical cancer patients. Patients with cervical cancer had low mean values of all lipid fractions. Women with the above malignancies also showed a significantly decreased CD3+ and CD4+ population (P < 0.001), while there was a significant increase in CD8+ cells (P < 0.005) compared to normal controls. Interestingly, a significant relationship (P < 0.05) was observed between CD8+cells and LDL-cholesterol among the cancer patients (r = 0.3652 and r = 0.4298 for carcinomas of breast and cervix, respectively).

Association of Dyslipidemia, Increased Insulin Resistance, and Serum CA 15-3 with Increased Risk of Breast Cancer in Urban Areas of North and Central India

Objective:

This study aims to determine the association of dyslipidemia and increased insulin resistance (IR) with increased breast cancer (BC) risk.

Materials and Methods:

The study group comprised 110 premenopausal and 143 postmenopausal, untreated female BC patients in the age range of 29–72 years. Control group consisted of 117 premenopausal and 141 postmenopausal healthy females in the age range of 23–75. Approximately 8-ml blood samples were drawn to measure various biochemical parameters. Serum glucose, total cholesterol, triglyceride (TG), and high-density lipoprotein-cholesterol were measured. Very low-density lipoprotein-cholesterol (VLDL-C) and LDL-C were calculated using Friedewald's formula. Serum insulin and serum CA 15-3 were estimated by immune enzymatic assay. IR was assessed using homeostasis model assessment IR index (HOMA-IR).

Results:

Clinical variables in the case and control groups were compared using the unpaired Student's t-test. The crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by binary logistic regression analysis. Pearson's correlation analysis was used to determine the association between CA 15-3 and variables of interest. Total cholesterol, TG, LDL, VLDL, serum glucose, serum insulin, HOMA-IR, and serum CA 15-3 were significantly higher (P < 0.001) in BC patients compared to those in controls. Significant adjusted ORs with 95% CI were found to be fasting glucose, total cholesterol, and TGs. We also found a significant positive correlation between total cholesterol, TG, LDL, serum glucose, serum insulin, HOMA-IR, and serum CA 15-3.

Conclusion:

This study confirms the association between dyslipidemia, IR, and increased BC risk.

Metabolic Syndrome and Breast Cancer Risk

Objective

The study was meant to estimate the prevalence of metabolic syndrome in patients with breast cancer and to establish its role as an independent risk factor on occurrence of breast cancer.

Materials and Methods

Fifty women aged between 40 and 80 years with breast cancer and fifty controls of similar age were assessed for metabolic syndrome prevalence and breast cancer risk factors, including age at menarche, reproductive status, live births, breastfeeding, and family history of breast cancer, age at diagnosis of breast cancer, body mass index, and metabolic syndrome parameters.

Results

Metabolic syndrome prevalence was found in 40.0% of breast cancer patients, and 18.0% of those in control group (P = 0.02). An independent and positive association was seen between metabolic syndrome and breast cancer risk (odds ratio = 3.037; 95% confidence interval 1.214-7.597).

Conclusions

Metabolic syndrome is more prevalent in breast cancer patients and is an independent risk factor for breast cancer.

VLDL and LDL, but not HDL, promote breast cancer cell proliferation, metastasis and angiogenesis

Abnormal lipoprotein profiles are associated with breast cancer progression. However, the mechanisms linking abnormal lipoprotein levels to breast cancer progression, especially metastasis, remain unclear. Herein, we found that L1 and L5 subfractions of LDL and VLDL, but not HDL, enhanced breast cancer cell viability. L1, L5, and VLDL also increased the in vitro tumorigenesis of breast cancer cells in anchorage-independent soft agar assay. In addition, L1, L5, and VLDL, but not HDL, increased the levels of mesenchymal markers Slug, Vimentin, and β-Catenin, and promoted breast cancer cell migration and invasion. L1, L5, and VLDL increased Akt Ser473 phosphorylation and promoted cell migration, which were reversed by the PI3K/Akt inhibitor wortmannin. Further in vitro angiogenesis assay and cytokine array analysis demonstrated that L1, L5, and VLDL enhanced secretion of angiogenic factors in breast cancer cells and promoted angiogenic activity. However, only VLDL reduced anchorage-dependent cell death and promoted lung metastasis in nude mice. In summary, our data suggest that L1, L5, and especially VLDL promote breast cancer progression and metastasis through Akt-induced EMT and angiogenesis, and provide a novel mechanism of how dyslipoproteinemia promotes breast cancer progression.

Dose response chemopreventive potential of allyl isothiocyanate against 7,12-dimethylbenz(a)anthracene induced mammary carcinogenesis in female Sprague-Dawley rats

The present study aimed to investigate the dose response chemopreventive potential of allyl isothiocyanate (AITC) against 7,12-dimethylbenz(a)anthracene (DMBA) induced mammary carcinogenesis in female Sprague-Dawley rats. Mammary tumor was induced by a single dose of DMBA (25 mg/rat) injected subcutaneously near mammary gland. We observed reduced body weight and increased in total number of tumors, tumor incidence and tumor volume in DMBA-induced rats. We also observed decreased antioxidant status (SOD, CAT, GPX and GSH) and increased lipid peroxidation (TBARS and LOOH) in plasma and mammary tissues. Increased levels of CYP450, Cyt-b5 and decreased levels of phase II (GST and GR) biotransformation enzymes noticed in liver and mammary tissues of DMBA-induced rats. Further, increased levels of lipid profile (TC, TG, PL and FFA) and lipoprotein (LDL and VLDL) were noticed. Whereas, decreased level of HDL in plasma and decreased levels of PL and FFA in mammary tissue. Oral administration of AITC different doses (10, 20 and 40 mg/kg bw) inhibited the tumor incidence and restored levels of biochemical markers. Biochemical findings are supported by histopathological studies. These results suggested that AITC at a dose of 20 mg/kg bw significantly exert chemopreventive potential against DMBA-induced mammary carcinogenesis.

Metabolic syndrome and postmenopausal breast cancer: systematic review and meta-analysis

OBJECTIVE

The role of metabolic syndrome (MS) and its individual components in postmenopausal breast cancer (PBC) risk is still unclear. We reviewed and summarized epidemiological studies assessing the association of MS with the risk of PBC.

METHODS

We conducted an electronic search, without restrictions, for articles published before October 31, 2012. Every included study was to report risk estimates with 95% CIs for the association between MS and PBC. Study-specific estimates were pooled using random-effects models.

RESULTS

Nine articles (with 6,417 cancer cases), all published in English, were included in the meta-analysis. MS was associated with a 52% increase in cancer risk (P < 0.001)-for the most part confined to noncohort studies (109% increased risk); the risk estimates changed little, depending on populations (United States and Europe) and definition of the syndrome (traditional vs nontraditional). The risk estimates for PBC were 1.12 (P = 0.068) for higher values of body mass index/waist circumference, 1.19 (P = 0.005) for hyperglycemia (higher fasting glucose or diabetes), 1.13 (P = 0.027) for higher blood pressure, 1.08 (P = 0.248) for higher triglycerides, and 1.39 (P = 0.008) for lower high-density lipoprotein cholesterol. All these estimates were lower than those associated with MS in the same studies.

CONCLUSIONS

MS is associated with a moderately increased risk of PBC. No single component explains the risk conveyed by the full syndrome.

Atypical plasma lipid profile in cancer patients: cause or consequence?

The aberrant blood lipoprotein levels in cancer patients are reported to be associated with cancer risk and mortality incidents however, there are several discrepancies in the previous reports. Hence the clinical usefulness of plasma/serum levels in risk stratification of a variety of cancers remains elusive. The present review highlights and compiles findings from different research groups regarding association of plasma lipoprotein levels with the risk of developing various types of cancer. We will discuss some prospective underlying mechanisms for this reported association. In addition to that the potential roles of plasma lipids in promoting carcinogenesis will be conferred.

Cholesterol transport and regulation in the mammary gland

The milk-producing alveolar epithelial cells secrete milk that remains after birth the principal source of nutrients for neonates. Milk secretion and composition are highly regulated processes via integrated actions of hormones and local factors which involve specific receptors and downstream signal transduction pathways. Overall milk composition is similar among mammalian species, although the content of individual constituents such as lipids may significantly differ from one species to another. The milk lipid fraction is essentially composed of triglycerides, which represent more than 95 % of the total lipids in human and commercialized bovine milk. Though sterols, including cholesterol, which is the major milk sterol, represent less than 0.5 % of the total milk lipid fraction, they are of key importance for several biological processes. Cholesterol is required for the formation of biological membranes especially in rapidly growing organisms, and for the synthesis of sterol-based compounds. Cholesterol found in milk originates predominantly from blood uptake and, to a certain extent, from local synthesis in the mammary tissue. The present review summarizes current knowledge on cellular mechanisms and regulatory processes determining intra- and transcellular cholesterol transport in the mammary gland. Cholesterol exchanges between the blood, the mammary alveolar cells and the milk, and the likely role of active cholesterol transporters in these processes are discussed. In this context, the hormonal regulation and signal transduction pathways promoting active cholesterol transport as well as potential regulatory crosstalks are highlighted.

Plasma level of LDL-cholesterol at diagnosis is a predictor factor of breast tumor progression

Background

Among women, breast cancer (BC) is the leading cancer and the most common cause of cancer-related death between 30 and 69 years. Although lifestyle and diet are considered to have a role in global BC incidence pattern, the specific influence of dyslipidemia in BC onset and progression is not yet completely understood.

Methods

Fasting lipid profile (total cholesterol, LDL-C, HDL-C, and triglycerides) was prospectively assessed in 244 women with BC who were enrolled according to pre-set inclusion criteria: diagnosis of non-hereditary invasive ductal carcinoma; selection for surgery as first treatment, and no history of treatment with lipid-lowering or anti-diabetic drugs in the previous year. Pathological and clinical follow-up data were recorded for further inclusion in the statistical analysis.

Results

Univariate associations show that BC patients with higher levels of LDL-C at diagnosis have tumors that are larger, with higher differentiation grade, higher proliferative rate (assessed by Ki67 immunostaining), are more frequently Her2-neu positive and are diagnosed in more advanced stages. Cox regression model for disease-free survival (DFS), adjusted to tumor T and N stages of TNM classification, and immunohistochemical subtypes, revealed that high LDL-C at diagnosis is associated with poor DFS. At 25 months of follow up, DFS is 12% higher in BC patients within the third LDL-C tertile compared to those in the first tertile.

Conclusions

This is a prospective study where LDL-C levels, at diagnosis, emerge as a prognostic factor; and this parameter can be useful in the identification and follow-up of high-risk groups. Our results further support a possible role for systemic cholesterol in BC progression and show that cholesterol metabolism may be an important therapeutic target in BC patients.

Comparison of Serum Lipid Profiles between Normal Controls and Breast Cancer Patients

BACKGROUND

Researchers have reported association of plasma/serum lipids and lipoproteins with different cancers. Increase levels of circulating lipids and lipoproteins have been associated with breast cancer risk.

AIM

THE AIM OF THIS STUDY IS TO COMPARE SERUM LIPID PROFILES: total-cholesterol (T-CHOL), triglyceride (TG), high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C) and very low density lipoprotein-cholesterol (VLDL-C) between breast cancer patients and normal participants.

MATERIALS AND METHODS

A total of 403 women in this study were divided into two groups in the period during May 2006-April 2007. Blood samples were collected from 249 patients with early stage breast cancer and 154 normal controls for serum lipid profiles (T-CHOL, TG, HDL-C, LDL-C and VLDL-C) analysis using Hitachi 717 Autoanalyzer (Roche Diagnostic GmbH, Germany). TG, LDL-C and VLDL-C levels in breast cancer group were significantly increased as compared with normal controls group (P < 0.001), whereas HDL-C and T-CHOL levels were not.

RESULTS

The results of this study suggest that increased serum lipid profiles may associate with breast cancer risk in Thai women. Further studies to group important factors including, cancer stages, types of cancer, parity, and menopausal status that may affect to lipid profiles in breast cancer patients along with an investigation of new lipid profiles to clarify most lipid factors that may involve in breast cancer development are needed.

Correlation Between Obesity and High Density Lipoprotein Cholesterol (HDL-C) in Breast Cancer Patients of Southern Rajasthan

Despite advances in management of breast cancer, etiology is still elusive. Diet, obesity and other life style factors have been implicated in its etiology. We assessed the role of obesity and HDL-C levels in patients with rural background in etiology of breast cancer. To know the relation between obesity and incidence of breast cancer in local population. Also to know serum HDL-C level in breast cancer and its correlation with breast cancer. A nested pilot study of 50 breast cancer patients was done and matched with 50 healthy women as controls. Obesity was measured by weight, height, BMI (Body Mass Index), waist circumference (WC), Hip Circumference (HC), WC/HC ratio, and Serum High Density Lipoprotein Cholesterol (HDL-C) was measured in patients and in controls. There was no significant difference in distribution of weight (p = 0.298), height (p = 0.653), BMI (p = 0.459) and WHR (p = 0.052) among cases and controls. HDL-C level was observed to be significantly lower in cases than control group (p = 0.017).Breast cancer patients of pre menopausal age had significantly low Weight (p = 0.037) and BMI (p = 0.011) than post menopausal patients. In our study population only low HDL-C level had significant correlation with breast cancer and none of the other anthropometric measurements were associated with breast cancer. However, large population based case control and cohort studies are needed to identify low serum HDL-C as an independent predictor of increased risk of breast cancer.

The role of high-density lipoproteins in reducing the risk of vascular diseases, neurogenerative disorders, and cancer

High-density lipoprotein (HDL) is one of the major carriers of cholesterol in the blood. It attracts particular attention because, in contrast with other lipoproteins, as many physiological functions of HDL influence the cardiovascular system in favourable ways unless HDL is modified pathologically. The functions of HDL that have recently attracted attention include anti-inflammatory and anti-oxidant activities. High anti-oxidant and anti-inflammatory activities of HDL are associated with protection from cardiovascular disease. Atheroprotective activities, as well as a functional deficiency of HDL, ultimately depend on the protein and lipid composition of HDL. Further, numerous epidemiological studies have shown a protective association between HDL-cholesterol and cognitive impairment. Oxidative stress, including lipid peroxidation, has been shown to be the mediator of the pathologic effects of numerous risk factors of Alzheimer's disease. Lifestyle interventions proven to increase HDL- cholesterol levels including "healthy" diet, regular exercise, weight control, and smoking cessation have also been shown to provide neuro-protective effects. This review will focus on current knowledge of the beneficial effects of HDL-cholesterol as it relates to cardiovascular diseases, breast and lung cancers, non-Hodgkin's lymphoma, as well as its neuroprotective potential in reducing the risk of Alzheimer's disease and dementia.

Free fatty acids enhance breast cancer cell migration through plasminogen activator inhibitor-1 and SMAD4

Obesity is a risk factor for breast cancer and is associated with increased plasma concentrations of free fatty acids (FFAs). We and others have demonstrated that FFA induces plasminogen activator inhibitor-1 (PAI-1) expression in a variety of cells. Emerging evidence supports elevation of PAI-1 as a prognostic marker for breast cancer. Therefore, we hypothesized that FFAs might increase expression of PAI-1 in breast cancer cells and facilitate breast cancer progression. Secreted PAI-1 was higher in invasive and metastatic MDA-MB-231 cells compared with less invasive and non-metastatic Hs578T cells. Utilizing FFAs with different saturation and chain lengths, we demonstrated that linoleic acid induced expression of PAI-1 in MDA-MB-231 cells. Linoleic acid also induced in vitro migration of MDA-MB-231. By contrast, other FFAs tested had little or no effect on PAI-1 expression or migration. Linoleic acid-induced breast cancer cell migration was completely inhibited by virally expressed antisense PAI-1 RNA. Furthermore, increased expression of PAI-1 by FFAs was not detected in the SMAD4-deficient MDA-MB-468 breast carcinoma cells. Electrophoretic mobility-shift assay confirmed that linoleic acid-induced expression of PAI-1 was mediated, at least in part, by SMAD4 in MDA-MB-231 cells. That linoleic acid induces PAI-1 expression in breast cancer cells through SMAD4 provides a novel insight into understanding the relationships between two migration-associated molecules, FFAs, and PAI-1.

Serum lipid profile of breast cancer patients

The purpose of this study was to carry out a comparative study to investigate the effect of lipid profile, oestradiol and obesity on the risk of a woman developing breast cancer. This study was carried out at the Komfo Anokye Teaching Hospital (KATH), Peace and Love Hospital, Oduom, Kumasi and Redeemed Clinic, Nima, Accra between May 2002 and March 2003. In this study, 200 consented women comprising 100 breast cancer patients (43 pre- and 57 post-menopausal) and 100 controls (45 pre- and 55 post-menopausal) with similar age range (25 to 80 years) were assessed for lipid profile, oestradiol and BMI. There was a significant increase in Body Mass Index (BMI) (p = 0.011), Total Cholesterol (TC) (p < 0.001), triglyceride (p = 0.026) and low density lipoprotein (LDL-cholesterol) (p = 0.001) of the breast cancer patients compared to the controls. With the exception of oestradiol (EST) that decreased, the lipid profile generally increased with age in both subjects and controls with the subjects having a much higher value than the corresponding control. There was also a significant positive correlation between BMI and TC (r2 = 0.022; p = 0.002) and also between BMI and LDL-cholesterol (r2 = 0.031; p = 0.0003). Apart from EST and LDL-cholesterol that were increased significantly only in the postmenopausal phase in comparison to the controls, BMI, TC and TG were increased in both pre-menopausal and post menopausal phases with HDL-cholesterol remaining unchanged. This study confirms the association between dyslipidaemia, BMI and increased breast cancer risk.

A longitudinal study of the metabolic syndrome and risk of postmenopausal breast cancer

The metabolic syndrome, characterized by abdominal obesity, high blood glucose levels, impaired glucose tolerance, dyslipidemia, and hypertension, is associated with increased risk of type 2 diabetes and coronary heart disease. Several studies have examined the association of the individual components of the metabolic syndrome with breast cancer; to date, however, no study has assessed the metabolic syndrome per se in relation to breast cancer risk. Furthermore, previous studies have relied only on baseline assessment of components of the syndrome. Therefore, we assessed the association of the metabolic syndrome with the risk of postmenopausal breast cancer among women in the 6% sample of subjects in the Women's Health Initiative clinical trial and the 1% sample of women in the observational study who had repeated measurements of the components of the syndrome during follow-up. We used Cox proportional hazards models to estimate hazard ratios and 95% confidence intervals for the association of breast cancer risk with the presence of the metabolic syndrome, as well as its components, at baseline and in time-dependent analyses. After exclusion of women with diabetes, among 4,888 women with baseline measurements, 165 incident cases of breast cancer were ascertained over a median of 8 years of follow-up. The presence of the metabolic syndrome at baseline was not associated with altered risk. Of the individual components measured at baseline, diastolic blood pressure showed a borderline positive association with breast cancer. In time-dependent covariate analyses, however, certain scenarios indicated a positive association between the metabolic syndrome and breast cancer, due primarily to positive associations with serum glucose, serum triglycerides, and diastolic blood pressure.

Diabetes, metabolic syndrome, and breast cancer: a review of the current evidence

Incidences of breast cancer, type 2 diabetes, and metabolic syndrome have increased over the past decades with the obesity epidemic, especially in industrialized countries. Insulin resistance, hyperinsulinemia, and changes in the signaling of growth hormones and steroid hormones associated with diabetes may affect the risk of breast cancer. We reviewed epidemiologic studies of the association between type 2 diabetes and risk of breast cancer and the available evidence on the role of hormonal mediators of an association between diabetes and breast cancer. The combined evidence supports a modest association between type 2 diabetes and the risk of breast cancer, which appears to be more consistent among postmenopausal than among premenopausal women. Despite many proposed potential pathways, the mechanisms underlying an association between diabetes and breast cancer risk remain unclear, particularly because the 2 diseases share several risk factors, including obesity, a sedentary lifestyle, and possibly intake of saturated fat and refined carbohydrates, that may confound this association. Although the metabolic syndrome is closely related to diabetes and embraces additional components that might influence breast cancer risk, the role of the metabolic syndrome in breast carcinogenesis has not been studied and thus remains unknown.

Low high-density lipoprotein cholesterol may signal breast cancer risk: recent findings and new hypotheses

Increasing bodyweight among women worldwide seems to be associated with a proportional rise in the number of women developing breast cancer. It is of utmost importance to obtain reliable biomarkers that may help clinicians to identify susceptible individuals among the growing population of women with excess adiposity. Our recent studies, reviewed within this article, support that adiposity-related metabolic disorders may represent high-risk phenotypes; specifically, we conclude that a low level of high-density lipoprotein cholesterol may be a reliable marker for breast cancer risk among overweight women. We tested our hypothesis among a large number of overweight women in the Norwegian Three County Cohort and the Norwegian cross-sectional study, the Energy Balance and Breast cancer Aspects (EBBA-I) study. Future studies should explore how genetic, environmental and behavioral factors may increase the susceptibility of overweight women to breast cancer, and how we can successfully establish targeted preventive strategies.

Alterations of serum cholesterol and serum lipoprotein in breast cancer of women

Fasting blood sample of 50 normal subjects (control) and 100 patients of breast cancer were investigated for serum total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, very low density lipoprotein, high density lipoprotein cholesterol:low density lipoprotein cholesterol ratio and total cholesterol:high density lipoprotein cholesterol ratio during breast cancer of women. Five cancer stages, types, age groups, parity and menopausal status were undertaken for the study. It was observed that there was a significant rise in serum total cholesterol and low density lipoprotein cholesterol whereas high density lipoprotein cholesterol and very low density lipoprotein cholesterol were not significant. The ratio of high density lipoprotein cholesterol:low density lipoprotein cholesterol and total cholesterol:high density lipoprotein cholesterol values increased significantly in breast cancer patients.

Metabolic and Hormonal Profiles: HDL Cholesterol as a Plausible Biomarker of Breast Cancer Risk. The Norwegian EBBA Study

Low serum high-density lipoprotein cholesterol (HDL-C) is an important component of the metabolic syndrome and has recently been related to increased breast cancer risk in overweight and obese women. We therefore questioned whether serum HDL-C might be a biologically sound marker of breast cancer risk. We obtained cross-sectional data among 206 healthy women ages 25 to 35 years who participated in the Norwegian EBBA study. We included salivary ovarian steroid concentrations assessed by daily samples throughout one entire menstrual cycle, metabolic profile with measures of adiposity [body mass index (BMI) and truncal fat percentage], serum concentrations of lipids and hormones (insulin, leptin, testosterone, dehydroepiandrostendione sulfate, insulin-like growth factor-I, and its principal binding protein), and mammographic parenchymal pattern. We examined how components of the metabolic syndrome, including low serum HDL-C, were related to levels of hormones, and free estradiol concentration in particular, and studied predictors of mammographic parenchymal patterns in regression models. In women with BMI ≥ 23.6 kg/m2 (median), overall average salivary estradiol concentration dropped by 2.4 pmol/L (0.7 pg/mL; 13.2% change in mean for the total population) by each 0.33 mmol/L (12.8 mg/dl; 1SD) increase in serum HDL-C (P = 0.03; Pinteraction = 0.03). A subgroup of women characterized by both relatively high BMI (≥23.6 kg/m2) and high serum LDL-C/HDL-C ratio (≥ 2.08; 75 percentile) had substantially higher levels of salivary estradiol by cycle day than other women (P = 0.001). BMI was the strongest predictor of overall average estradiol with a direct relationship (P&lt; 0.001). Serum HDL-C was inversely related to serum leptin, insulin, and dehydroepiandrostendione sulfate (P &lt; 0.001, P &lt; 0.01, and P &lt; 0.05, respectively). There was a direct relationship between breast density and healthy metabolic profiles (low BMI, high serum HDL-C; P &lt; 0.001) and salivary progesterone concentrations (P &lt; 0.05). Our findings support the hypothesis that low serum HDL-C might reflect an unfavorable hormonal profile with, in particular, increased levels of estrogens and gives further clues to biomarkers of breast cancer risk especially in overweight and obese women.

Serum high-density lipoprotein cholesterol, metabolic profile, and breast cancer risk

BACKGROUND

The prevalence of metabolic syndrome (obesity, glucose intolerance, low serum high-density lipoprotein cholesterol [HDL-C], high serum triglycerides, hypertension) is high and increasing in parallel with an increasing breast cancer incidence worldwide. HDL-C represents an important aspect of the syndrome, yet its role in breast cancer is still undefined.

METHODS

In two population-based screening surveys during 1977-1983 and 1985-1987, serum HDL-C was assayed enzymatically among 38,823 Norwegian women aged 17-54 years at entry. Height, weight, blood pressure, serum lipids, fat and energy intake, physical activity, parity, oral contraceptive use, hormone therapy use, alcohol intake, and tobacco use were also assessed. We used Cox proportional hazards modeling to estimate the relative risk (RR) of breast cancer associated with serum HDL-C levels and to adjust for potential confounding variables. We performed stratified analyses to evaluate effect modification by body mass index (BMI) and menopausal status. All statistical tests were two-sided.

RESULTS

During a median follow-up of 17.2 years, we identified 708 cases of invasive breast cancer. In multivariable analysis, the risk of postmenopausal breast cancer was inversely related to quartile of HDL-C (P(trend) =.02). Among women with HDL-C above 1.64 mmol/L (highest quartile) versus below 1.20 mmol/L (lowest quartile), the relative risk was 0.75 (95% confidence interval [CI] = 0.58 to 0.97). The HDL-C association was confined to women in the heavier subgroup (BMI > or =25 kg/m2), for whom the relative risk of postmenopausal breast cancer in those with HDL-C above 1.64 mmol/L versus below 1.20 mmol/L was 0.43 (95% CI = 0.28 to 0.67; P(trend)<.001; P(interaction) =.001).

CONCLUSION

Low HDL-C, as part of the metabolic syndrome, is associated with increased postmenopausal breast cancer risk.

Relationship between serum prolactin levels and histology of benign and malignant breast lesions: a detailed study of 153 consecutive cases

This study was aimed at investigating the relationship between serum prolactin levels and the morphology of operable female breast lesions. One hundred fifty-three consecutive patients with operable benign and malignant breast lesions in whom preoperative serum prolactin levels had been determined were stratified into five groups according to their serum prolactin levels. The histologic findings in these groups were analyzed and compared. Most patients (93%) had serum prolactin levels within the normal limits. Of the 54 patients with benign lesions, only 4(7%) had slightly elevated serum prolactin levels. Two of these patients had fibroadenomas, one had a phyllodes tumor and one had fibrocystic change. Of the 99 patients with carcinoma, 7 (7%) had hyperprolactinemia. Five of the seven tumors were invasive and two were in situ. All seven tumors were of low or intermediate grade of malignancy. The two cases with the highest prolactin levels (3057 and 1822 mU/L) were both intermediate-grade ductal carcinoma in situ (DCIS). It is concluded that the great majority of patients presenting with operable breast lesions have normal serum prolactin levels, and that elevated levels, when present, occur with equal frequency in patients with benign and malignant breast lesions. Hyperprolactinemic patients presenting with carcinoma in this study, none of whom had a history of recent pregnancy or lactation, tended to have histologically low- or intermediate-grade tumors, but this needs to be confirmed by investigating more cases.

Serum lipids, lipoproteins and sex-hormone binding globulin in breast cancer

Serum levels of various lipid parameters, i.e., triglycerides, total cholesterol, alpha lipoprotein or high density lipoprotein (HDL)-cholesterol and beta lipoprotein or low density lipoprotein (LDL)-cholesterol were measured in a total of 138 histologically proven cases of breast cancer along with 146 control women. The mean levels of serum triglycerides, total cholesterol and LDL-cholesterol were found to be significantly higher in breast cancer cases as compared to controls. However, lower mean levels of serum HDL-cholesterol and sex-hormone binding glubulin (SHBG) were observed in breast cancer patients than the control subjects. The results indicate a probable relation between serum lipids and the activity of sex-hormones. Moreover, the study reflects an overall disturbance of lipid metabolism in the pathological process of breast cancer.

Apolipoprotein E genetic polymorphism, serum lipoproteins, and breast cancer risk

Apolipoprotein E (apoE) is a polymorphic gene involved in lipid metabolism with three common variant alleles (epsilon2, epsilon3, and epsilon4). The epsilon4 allele has been associated with elevated levels of cholesterol as well as greater risk of coronary heart disease and Alzheimer's disease. In this case-control study we examined whether apoE genotype affected the association between serum lipids and breast cancer risk. In a subset of a study in western New York, 260 women with incident, primary breast cancer and 332 community controls were interviewed and provided blood samples. Polymerase chain reaction-restriction fragment length polymorphism analyses of the apoE polymorphism were performed. Participants were classified as apoE2 (epsilon2, epsilon2 or epsilon2, epsilon3), apoE3 (epsilon3, epsilon3), or apoE4 (epsilon4, epsilon4 or epsilon4, epsilon3). No unconditional logistic regression was used to compute adjusted odds ratios (ORs) and 95% confidence intervals (CI). Compared with women with the apoE3 genotype, there were no associations with risk for women with the apoE2 (OR=1.0; 95% CI=0. 91-1.64) or apoE4 genotype (OR=0.97; 95% CI=0.63-1.54). Higher serum levels of total cholesterol, HDL cholesterol, and LDL cholesterol were not associated with risk, either in the total sample or among subgroups of women defined by apoE genotype. Women with the highest serum triglyceride levels had an increase in risk (OR=1.63; 95% CI=1. 03-2.59) compared to women with the lowest levels. This effect was not apparent among women with the apoE2 or apoE3 genotype, but much stronger among women with the apoE4 genotype (OR=4.69; 95% CI=1. 49-14.7). These data suggest that the apoE4 genotype may modify the association between serum triglycerides and breast cancer risk.

Proteinases and myocardial extracellular matrix turnover

Extracellular structural remodeling is the compensatory response of the tissue following pathological stage. Myocardial infarction, which leads to adverse remodeling, thinning of the ventricle wall, dilatation and heart failure, is one of the leading causes of death. Remodeling implies an alteration in the extracellular matrix and in the spatial orientation of cells and intracellular components. The extracellular matrix is responsible for cardiac cell alignment and myocardial structural integrity. Substances that break down the extracellular matrix, specialized proteinases as well as inhibitors of proteinases, appear to be normally balanced in maintaining the integrity of the myocardium. Myocardial infarction leads to an imbalance in proteinase/antiproteinase activities causing alterations in the stability and integrity of the extracellular matrix and adverse tissue remodeling. To explore mechanisms involved in this process and, in particular, to focus on matrix metalloproteinases, their inhibitors, and activators, an understanding of proteinase and antiproteinase is needed. This review represents new and significant information regarding the role of activated matrix proteinases antiproteinases in remodeling. Such information will have a significant impact both on the understanding of the basic cell biology of extracellular matrix turnover, as well as on potential avenues for pharmacological approaches to the treatment of ischemic heart disease and failure.

Elevated levels of plasma triglycerides are associated with histologically defined premenopausal breast cancer risk

Lipids and lipoproteins have been associated with breast cancer risk; however, published results have been inconsistent. To clarify these associations, we measured fasting lipids in women undergoing breast biopsies. A case-control study examined the association of fasting levels of lipids with histologically defined breast cancer risk. Four groups of premenopausal women were assembled on the basis of histological appearance of breast tissue: 1) no epithelial proliferation (n = 102), 2) proliferation without atypia (n = 53), 3) atypical hyperplasia or carcinoma in situ (n = 53), and 4) node-negative invasive cancer (n = 102). A postoperative fasting blood specimen was analyzed for cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides. Demographics, risk factors, diet, physical activity, fasting weight, and skin-fold thickness were measured. Triglyceride levels were significantly higher in women with node-negative invasive cancer (0.94 +/- 1.04 mg/ml) than in those with no epithelial proliferation (0.83 +/- 1.04 mg/ml, p = 0.03). This association persisted after adjustment for age, body size, lipids, reproductive and familial risk factors, and previous benign breast problems (p < 0.01), in keeping with an independent association of elevated triglycerides with breast cancer risk.

Application of 31P NMR spectroscopy to monitor chemotherapy-associated changes of serum phospholipids in patients with malignant lymphomas

31P spectra were obtained from 22 healthy volunteers and 35 patients with malignant lymphomas. Sera from patients were collected at the time of diagnosis and at several time-points during therapy. Long-term follow-up studies showed a good correlation between the 31P NMR spectra of sera and the clinically evident response of the disease to the chemotherapy. During therapy leading to remission resonance from phospholipids increased progressively resulting in spectra similar to those seen in normal sera. By contrast, in patients who did not respond to therapy the intensities of the phospholipid peaks remained relatively low or became progressively reduced as the disease progressed. To understand the source of the spectral differences, we also examined the concentrations of high-density lipoprotein, low-density lipoprotein, cholesterol, and triglycerides. In individuals responding to the treatment, both high-density lipoprotein and cholesterol increased to the point where they were statistically equivalent to those from healthy volunteers.

Perturbations of triglycerides but not of cholesterol metabolism are prevented by anti-tumour necrosis factor treatment in rats bearing an ascites hepatoma (Yoshida AH-130)

Rats transplanted with the ascites hepatoma Yoshida AH-130 developed a severely progressive cachexia, characterised by marked alterations in protein and lipid metabolism. In particular, high levels of serum triglycerides and free fatty acids were associated with altered levels and distribution of plasma cholesterol, with increased total and very low-density lipoprotein-low-density lipoprotein (VLDL-LDL) cholesterol and reduced high-density lipoprotein (HDL) cholesterol. The tumour cells showed high rates of cholesterol synthesis and elevated content of free and esterified cholesterol, whereas total cholesterol synthesis was reduced in the host liver. To determine whether these perturbations could be related to the elevation of tumour necrosis factor alpha (TNF-alpha) previously shown in the AH-130 bearers (Tessitore L, Costelli P, Baccino FM 1993, Br J Cancer, 67, 15-23), either anti-TNF polyclonal antibodies or non-immune IgGs were injected daily after tumour transplantation. The anti-TNF treatment neither affected tumour growth nor prevented the serum cholesterol changes, while attenuating the hypertriglyceridaemia and the elevated serum free fatty acid levels. These data indicate that TNF does not appear to be directly involved in the altered cholesterol metabolism in AH-130 hosts, thus supporting the view that cholesterol metabolism and lipid metabolism are regulated differently during tumour growth.

Effect of adjuvant chemotherapy on the circulating levels of pituitary hormones in postmenopausal breast cancer patients

The effect of adjuvant chemotherapy on the circulating levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and prolactin (PRL) has been investigated in postmenopausal breast cancer patients. In the patients who received adjuvant CMF-chemotherapy, there was a significant decrease in the circulating FSH, LH and PRL levels compared to healthy age-matched controls. A positive correlation was found between this decline in the FSH, LH and PRL values and the regression of tumor size following chemotherapy regimen.

Serum vitamin E level in patients with breast cancer

In this study, the serum vitamin E (total tocopherol) levels in patients with breast cancer (n = 100) and healthy controls (n = 70) were measured. The mean values for vitamin E were found to be 0.44 mg/100 ml in breast cancer patients and 1.108 mg/100 ml in controls. In the statistical evaluation, the vitamin E levels in breast cancer patients are significantly lower than in the controls (P < 0.05). The influence of factors such as suckling period, age of first gestation, smoking status and dietary habits were also studied.

Serum lipids and apolipoproteins in women with breast masses

BACKGROUND

Human mammary tissue metabolizes lipids from plasma, a process affected by female gonadal hormones. Both benign and malignant proliferation of breast tissue in women have been associated with changes in plasma lipid and lipoprotein levels.

METHODS

One hundred consecutive women with breast masses (50 malignant, 50 benign) had diagnostic biopsies followed by axillary node dissection in those with cancer. Fasting serum samples were taken just prior to biopsy and analyzed for lipid fatty acid and lipoprotein levels. Malignant breast tissue was analyzed for hormone receptor binding.

RESULTS

Low-density lipoprotein (LDL) components (total cholesterol, LDL-cholesterol, apolipoprotein B) were increased, but not significantly, in cancer patients compared to those with benign masses. Decreased levels of LDL-associated components were found in women with cancer recurrence by 3 years. Three apolipoproteins of high-density lipoprotein (apolipoprotein A-I, apolipoprotein A-II, apolipoprotein D) were more affected by the presence of breast masses than the lipids were. Fibrocystic disease, type of hormone binding, and recurrence within 3 years were significantly related to apolipoprotein changes, especially apolipoprotein D levels with hormone receptor binding and the apolipoprotein A-I/apolipoprotein B ratio with breast cancer recurrence.

CONCLUSIONS

Prior to diagnostic biopsy, serum lipid and apolipoprotein components of low-density lipoproteins were increased in women with fibrocystic disease and early stage cancer but decreased in women with early recurrence. However, apolipoprotein A-I, apolipoprotein A-II, and apolipoprotein D, of the high-density lipoproteins, were more affected than serum lipids. The ratio of apolipoprotein A-I to apolipoprotein B serum levels at time of biopsy was the best predictor of cancer recurrence.

Risk of breast cancer in relation to blood lipids: a prospective study of 31,209 Norwegian women

In this prospective study, the relationship between blood lipids and breast cancer risk was examined. Between 1977 and 1983, 31,209 Norwegian women, 20 to 54 years of age, attended a health screening carried out by the Norwegian National Health Screening Services. The screening consisted of a questionnaire, anthropometric measurements, and nonfasting blood drawn for analysis of total serum cholesterol (TC), triglyceride (TG), and high density lipoprotein (HDL) cholesterol. Low density lipoprotein (LDL) cholesterol was calculated by the Friedewald's formula. During the seven to 13 years of follow-up, 302 breast cancer cases were identified by linkage to the Norwegian Cancer Registry. After adjustment for some of the known risk factors of breast cancer, the relative risk of women in the highest quartile of TC compared with women in the lowest quartile was 0.87 (95 percent confidence interval [CI] = 0.61-1.23). The corresponding relative risks and CIs were 0.82 (CI = 0.58-1.16) for TG, 1.02 (CI = 0.73-1.42) for HDL, and 0.93 (CI = 0.67-1.29) for LDL. No association between breast cancer risk and blood lipids was found in the total population, nor when the data were divided into those diagnosed before or after the age of 50 as a dividing line between pre- and postmenopausal diagnosis.

Use of proton nuclear magnetic resonance spectroscopy of plasma in screening for malignant disease

In 1986, narrow plasma proton nuclear magnetic resonance (NMR) methyl and methylene line widths were reported to be associated with malignant disease, but more recent studies have not confirmed this relationship. The authors analyzed 106 plasma samples from healthy control subjects and patients with cirrhosis, hepatocellular carcinoma, metastatic liver tumors, other untreated cancers, and hyperlipidemia. NMR spectroscopy was performed using a proton NMR spectrometer operating at 399.65 MHz. A significant difference was found between the mean line widths of the plasma methyl resonances in control subjects and those in patients with cancer or hyperlipidemia. However, no significant difference was found between the mean plasma methylene line widths in control subjects and patients with cancer. Plasma samples from patients with liver disease or hyperlipidemia showed a characteristic methylene spectral pattern. The methylene pattern could be separated into three types: type A had a small peak on the right shoulder of the main peak; type B was a sharp single peak; and type C was a broad single peak. All control subjects had type A pattern; patients with liver disease had type C pattern; and patients who had hyperlipidemia had type B pattern, and hyperlipidemia may affect methyl and methylene line widths in NMR spectra. Because the methyl and methylene levels and their average line widths correlated inversely with triglyceride levels, considering the spectral patterns that indicate hyperlipidemia should decrease false-positive results and make the methyl line width useful for cancer screening.

Associations between breast cancer, plasma triglycerides, and cholesterol

A case-control study investigating the association between plasma lipids and breast cancer was conducted among women aged 30-80 in Buffalo, NY. All eligible women from a large breast clinic and two area physicians' offices were requested to participate over a one-year period. Subjects completed a health questionnaire and donated a fasting blood sample prior to diagnostic breast biopsies. The 83 women found to have breast cancer (cases) had significantly higher plasma triglyceride values than did the 113 women found not to have breast cancer (controls). Lower plasma beta-carotene values were associated with breast cancer, but only in those women with elevated triglyceride or cholesterol. Plasma cholesterol values were lower in those breast cancer cases presenting with more advanced stages of cancer, suggesting that metabolic effects of clinical and preclinical breast cancer may lower cholesterol levels. Although the limitations of case-control studies are well-recognized, these data suggest an etiologic role for plasma triglycerides and beta-carotene or for related dietary factors.

Effect of triglyceride levels on methyl and methylene envelope line widths in proton nuclear magnetic resonance spectroscopy of human plasma

Recent studies have described a relation between the line widths of the methyl and methylene resonance envelopes in the proton nuclear magnetic resonance spectrum of human plasma and the occurrence of cancer. An average line width of less than 33 Hz has been reported to correlate with the presence of cancer, whereas greater line widths have not. In 26 normal volunteers, we found a significant inverse correlation between fasting triglyceride level and plasma spectral line width. We also observed that dietary lipids have measurable effects on spectral line widths. In another sample of seven normal persons (three of whom had elevated plasma triglyceride levels), the line widths of whole plasma varied widely (mean, 35.6 +/- 8.8 Hz); however, the mean line widths of the lipoprotein fractions isolated from those samples differed greatly, but the variance within each fraction was small (very-low-density lipoprotein, 22.0 +/- 1.9 Hz; low-density lipoprotein, 35.0 +/- 2.8; high-density lipoprotein, 28.8 +/- 1.9). The results of this study indicate that the plasma triglyceride level has a profound effect on the average spectral line width of plasma. This effect can be explained by the relative amounts of lipoprotein fractions in whole plasma. Plasma triglyceride concentrations of more than 1.24 mmol per liter (greater than 110 mg per deciliter), whatever the source, produce average plasma methyl and methylene line widths of less than 33 Hz.

Plasma lipids in premenopausal women with mammographic dysplasia

Epidemiological evidence indicates that mammographic dysplasia is associated with an increased risk of breast cancer, particularly in premenopausal women. To examine biochemical associations with mammographic dysplasia we have compared premenopausal women with different patterns of the breast parenchyma on mammography. One group had extensive radiological dysplasia (n = 30) and the other no dysplasia (n = 16). Both groups were recruited from mammographic units in the same way and then compared according to epidemiological risk factors, anthropometric measures, nutrient intake and plasma levels of oestradiol, progesterone and prolactin obtained in both follicular and luteal phases of the menstrual cycle as well as total plasma cholesterol and lipid fractions. Women with mammographic dysplasia were found to be leaner, more often nulliparous and to consume more alcohol than women without these radiological changes. Mammographic dysplasia and a family history of breast cancer were found to be independently associated with significantly higher levels of high density lipoprotein cholesterol (HDL-C) after taking into account the possible confounding effects of percentage body fat, parity and consumption of alcohol and dietary fat. Triglyceride levels were also independently associated with a family history of breast cancer. We conclude that further investigation is warranted of the role of plasma lipids in relation to breast cancer risk.

1H NMR studies on human plasma lipids from newborn infants, healthy adults, and adults with tumors

The 1H NMR spectra of the lipid region of human plasma from healthy adults, neonates, and patients with malignant and nonmalignant tumors have been recorded on a JNM-GX400 FT spectrometer operating at 399.6 MHz for protons. The chemical shifts of methylene and methyl groups of plasma lipids were measured with respect to the higher field component of the methyl proton resonance of the lactate molecule. The results show that there are changes in the chemical shifts of the methylene proton resonances among the plasma from healthy adults, adults with tumors, and neonates. The shifts observed in the case of cancer patients and neonates are in the direction opposite to the shift measured from the plasma of healthy adults. Thus, the observed changes cannot be explained by the activity in the cell proliferation of tissues which is high in the cases of both healthy neonates and patients with malignant tumors, but they most probably reflect the different lipoprotein compositions of neonates, healthy adults, and adults with tumors.

Oral contraceptives and breast cancer. A review

Case-control and cohort studies published between 1977 and 1988 were reviewed with the purpose to evaluate the relationship between use of oral contraceptives (OC-use) and breast cancer risk, tumour biology and tumour prognosis with special emphasis on early OC-use. The risk of breast cancer was assessed in 30 case-referent studies and 5 cohort studies, and the prognosis of breast cancer had been studied in 9 reports. Definition of OC-use, prevalence of OC-use, latency time between start of OC-use and tumour diagnosis, case identification and choice of referents, study size, study quality were assessed. The outcome of the studies is presented. From the results of the analyses the author concludes that there is no overall risk for breast cancer among OC-users. However, with the emphasis on early OC-use, consistent results seem to emerge showing an increased risk of premenopausal breast cancer, when the possible bias of different latency times is taken into account. Also results on breast cancer incidence in early exposed age groups, tumour biology and prognosis in early OC-users with breast cancer support a genuine risk relationship. The effects of different OC-brands and dose, and the risk of peri- and postmenopausal breast cancer after early OC-use can at present not be assessed.