Flaxseed and its components reduce metastasis after surgical excision of solid human breast tumor in nude mice

This study determined the effect of 10% flaxseed (FS) and its components, secoisolariciresinol diglycoside (SDG) and flaxseed oil (FO) alone or in combination (SDG+FO), on the metastasis and recurrence of human breast tumor after excision in nude mice. Mice were injected orthotopically with human breast cancer cells (MDA-MB-435) and fed basal diet (BD). When the tumors reached an average size of 110 mm(2) (0.9 g), surgical excisions were performed, and the mice were assigned to one of five diet groups for 7 weeks. The total incidence of metastasis was significantly lower in the FS, SDG, and SDG+FO groups. Reduced lung and lymph node metastases were observed in the FS and SDG+FO groups. In the FS and FO groups, a greater reduction in lung and total metastases was found when excised tumors were 0.9 g. There was no significant difference in tumor recurrence among groups. In conclusion, FS and its components inhibited tumor metastasis but not tumor recurrence after surgical excision of the primary tumor.     

Flaxseed attenuates the tumor growth stimulating effect of soy protein in ovariectomized athymic mice with MCF-7 human breast cancer xenografts

In several epidemiological studies, a phytoestrogen-rich diet containing lignans and isoflavones is associated with reduced breast cancer risk, but experimental findings are controversial. In postmenopausal mammary cancer xenograft model, flaxseed (FS), a rich source of plant lignans, reduced breast cancer growth, while soy protein (SP), a rich source of isoflavones, enhanced it. The intake of phytoestrogens is increasing particularly among postmenopausal women, emphasizing the importance of elucidating their interactive effects on breast cancer. Our study determined the effect of FS and SP diets, alone and in combination, on the established human breast cancer MCF-7 tumor growth in ovariectomized athymic nude mice. Tumor bearing mice were divided into 4 groups and fed for 25 weeks either the basal diet (BD), or BD supplemented with 10% FS, 20% SP or 10% FS and 20% SP. After estrogen deprivation, FS regressed the tumor size similar to that of control. SP initially regressed the tumors but starting at week 13, the tumors regressed significantly less than in control and 43% of the tumors were regrowing until the end of the experiment and were significantly larger in size than in control. The combination of SP with FS reduced the tumor growth similar to that of control, as suggested also by the reduced tumor cell proliferation index. In conclusion, dietary FS did not stimulate the growth of estrogen responsive MCF-7 cancers in ovariectomized mice, while long-term consumption of SP did. Furthermore, FS reduced the tumor growth stimulating effect of SP to the same level as control, suggesting tumor growth attenuating effect of FS.     

ER-α36在乳腺癌组织中的表达及临床意义

目的:研究ER-α36(estrogen receptor-alpha 36)在乳腺癌组织中的表达状态及在乳腺癌发生、发展和临床预后中的作用。方法:选取河南省肿瘤医院乳腺科及郑州大学第一附属医院乳腺科2010年3月-2013年3月间653例乳腺癌组织,用RT-PCR技术和免疫组化技术检测组织中ER-α36、ER-α66、PR和Her-2的表达,分析ER-α36的表达与上述指标及临床病理特征之间的关系。结果:ER-α36的总体表达率是40%（261/653）。在Her-2阳性组织中的表达率63%（78/124）,显著高于阴性组35%（183/529）,P<0.05。在ER-α66/PR/Her-2三阴性组织中的表达率66%（69/104）,显著高于非三阴性组35%（192/549）,P<0.05。在ER-α66阳性和阴性样本中及在PR阳性和阴性样本中的表达率,差异没有统计学意义(P>0.05)。在III+IV期乳腺癌组织中的阳性表达率54%（165/305）,明显高于I+II期28%（96/348）,P<0.05。在淋巴结转移阳性乳腺癌组织中的表达率55%（184/335）,显著高于无转移组织24%（77/318）,P<0.05。结论:ER-α36可能在乳腺癌的发生、发展及淋巴结转移过程中具有重要作用,并与Her-2的表达、乳腺癌分期及淋巴结转移有关,有望成为新的肿瘤标记物及临床诊治的新靶点。     

Plasma insulin-like growth factor I levels in rats are reduced by dietary supplementation of flaxseed or its lignan secoisolariciresinol diglycoside

Flaxseed and its lignan secoisolariciresinol diglycoside (SDG) inhibit mammary tumor development in rats. Increased plasma insulin-like growth factor I (IGF-I) concentrations are associated with increased breast cancer risk. Therefore, the effect of flaxseed (5%) or SDG (1.5 mg/day) supplementation on plasma IGF-I levels was examined in rats treated with or without N-methyl-N-nitrosourea (MNU). In MNU-free rats, flaxseed and SDG reduced plasma IGF-I levels, which were inversely related to urinary lignan excretion. Only flaxseed significantly reduced plasma IGF-I concentrations in MNU-treated rats. The anticancer effect of flaxseed and SDG may be related, in part, to reductions in plasma IGF-I.     

Dietary flaxseed enhances the inhibitory effect of tamoxifen on the growth of estrogen-dependent human breast cancer (mcf-7) in nude mice.

PURPOSE: This study determined the effect of 10% dietary flaxseed (FS) and tamoxifen (TAM), alone and in combination, on the growth of estrogen-dependent human breast cancer (MCF-7) in athymic mice with or without 17beta-estradiol (E2) supplementation. EXPERIMENTAL DESIGN: Ovariectomized mice received injection with MCF-7 cells, were implanted with an E2 pellet (1.7 mg), and fed the basal diet (BD). When tumor reached approximately 40 mm2, the E2 implant was removed, and mice were randomized to the following groups and maintained at either low (E2 pellet removed) or high E2 level (new E2 pellet implanted) for 6 weeks: (a) positive control with new E2 pellet, fed BD, (b) negative control with no E2 implant, fed BD, (c) TAM group with TAM pellet (5 mg) implant, fed BD, (d) FS group fed 10% FS, (e) FS+TAM group with TAM implant, fed 10% FS. Tumor growth was monitored weekly. RESULTS: At low E2 level, FS regressed the pretreatment tumor size by 74%. TAM regressed tumor initially but later induced an increase so that the tumor size was finally similar to the pretreatment size. A tumor regression >53% was induced by FS+TAM than by TAM alone. At high E2 level, FS, TAM, and FS+TAM inhibited the tumor growth by 22, 41, and 50%, respectively, compared with the positive control. Decreased tumor size was attributable to reduced tumor cell proliferation and increased apoptosis. CONCLUSIONS: FS inhibited the growth of human estrogen-dependent breast cancer and strengthened the tumor-inhibitory effect of TAM at both low and high E2 levels.     

Phytoestrogen intake from foods,during adolescence and adulthood,and risk of breast cancer by estrogen and progesterone receptor tumor subgroup among Ontario women

Phytoestrogen intake may reduce breast cancer risk and limited evidence suggests this association may hold for hormone receptor‐positive tumors only. The study aims were to assess whether the association between phytoestrogen intake during adolescence and adulthood and breast cancer risk varies by estrogen and progesterone receptor (ERPR) tumor subgroup. Cases were identified from the Ontario Cancer Registry (2002–2003), and ERPR status was ascertained from pathology reports for 81% of cases (n = 2,438). Controls were identified through random digit dialing of Ontario households (n = 3,370). Published phytoestrogen food values were applied to food frequency questionnaire responses to assess isoflavone, lignan and total phytoestrogen intake, during adolescence and adulthood. Polytomous multivariate logistic regression was used to estimate adjusted odds ratios (ORs) for association between phytoestrogen intake and breast cancer risk by hormone receptor ERPR tumor subgroups. Among premenopausal women, few associations were observed for adolescent or adult phytoestrogen intake across all tumor subgroups. Among postmenopausal women, adolescent phytoestrogen intake (isoflavone, lignan and total) was associated with reduced risk across all hormone receptor subgroups; however, statistical significance was most consistent within the ER+PR+ subgroup. For example, ER+PR+ postmenopausal breast cancer risk was associated with adolescent phytoestrogen intake (highest vs. lowest: OR = 0.79; 95% confidence interval: 0.65–0.96). Among all women and postmenopausal women, ORs for high adult lignan intake were all below 1.0 within each tumor subgroup, suggesting reduced breast cancer risk, although none reached statistical significance. In conclusion, adolescent phytoestrogen intake was associated with reduced postmenopausal breast cancer, particularly for ER+PR+ tumor subgroup.     

Vimentin和E-cadherin蛋白在乳腺癌组织中的表达及其临床意义

目的: 研究波形蛋白（Vimentin）和E-钙黏蛋白（E-cadherin）在人乳腺癌组织中的表达及其临床意义。方法: 回顾性分析2014 年1 月至2016 年1 月在安徽医科大学附属巢湖医院接受乳腺癌根治术的56 例乳腺癌组织和相应癌旁组织标本以及病历资料,用免疫组织化学染色法和qPCR 分别检测癌组织中Vimentin、E-cadherin 蛋白和mRNA的表达,分析Vimentin 和E-cadherin蛋白在乳腺癌组织中的表达与临床病理特征的关系。用Logistic 多因素回归分析影响Vimentin 和E-cadherin 蛋白表达的独立因素,用Spearman 分析Vimentin 与E-cadherin 蛋白表达的相关性,用Kaplan-Meier 分析Vimentin 和E-cadherin 蛋白表达与预后的关系,用ROC曲线分析Vimentin 和E-cadherin 蛋白表达对预后的诊断。结果: 56 例乳腺癌组织中Vimentin 和E-cadherin 蛋白高表达率分别为76.79%和19.64%;其中47 例（47/56,83.93%）乳腺癌组织中Vimentin mRNA 的表达量显著高于癌旁组织（P<0.05）,46 例（46/56,82.14%）乳腺癌组织中E-cadherin mRNA的表达量显著低于癌旁组织（P<0.05）。Vimentin 蛋白表达与肿瘤大小、淋巴结转移、脉管侵袭、组织学分级、临床分期、分子分型、Ki67 阳性、ER阴性、PR阴性及HER2 阴性表达均有关（均P<0.05）;E-cadherin 蛋白表达与淋巴结转移、脉管侵袭、组织学分级、临床分期、分子分型、Ki67 阳性、ER阴性、PR阴性及HER2 阴性表达均有关（均P<0.05）。肿瘤大小、淋巴结转移、脉管侵袭、组织学分级、临床分期、分子分型、Ki67 阳性、ER阴性、PR阴性及HER2 阴性表达均是促进Vimentin 和E-cadherin 表达的独立影响因素（P<0.05）,且Vimentin 与E-cadherin 蛋白表达呈负相关关系（P<0.05）。Vimentin 蛋白高表达的患者3 年生存率为67.44%,E-cadherin 蛋白低表达的患者3 年生存率为68.89%。结论: 在乳腺癌组织中Vimentin高表达和E-cadherin低表达与乳腺癌发生发展、侵袭转移及患者预后有关,可作为临床诊断与预后的评价指标。     

Effect of dietary fat on growth of MCF-7 and MDA-MB231 human breast carcinomas in athymic nude mice: relationship between carcinoma growth and lipid peroxidation product levels

Human breast carcinoma cell lines MCF-7 and MDA-MB231 were transplanted s.c. to female athymic nude mice at 3-4 weeks of age. At 7-10 days after transplantation, the mice were divided into groups and fed for 6-8 weeks one of the following semi-purified diets containing different amounts and types of fat, i.e. 5% corn oil, 20% corn oil, 20% butter, 19% beef tallow/1% corn oil and 19% fish (Menhaden) oil/1% corn oil. In addition experiments, the fish oil diets were supplemented with antioxidants (vitamin E, 8 g or 2000 IU/kg diet plus tertiary butyl hydroquinone, TBHQ, 4 g/kg diet) or ferric citrate (3 g/kg diet). Tumor peroxidation product levels were assessed by measuring 2-thiobarbituric acid reactants (TBA assay). At the termination of the studies (6-8 weeks of diet feeding) mean human breast carcinoma volume (MCF-7 and MDA-MB231) was the largest in mice fed the 20% corn oil diet, intermediate in mice fed the butter or beef tallow diets and the least in mice fed the fish oil diet. The difference in mean tumor volumes among mice fed the 20% corn oil diet and those fed the fish oil diet was significant (P less than 0.01). When comparing low (5% corn oil) and high (20% corn oil) fat diets, numerical increases in human breast carcinoma volume (MCF-7 and MDA-MB231) were consistently observed in the high-fat diet groups but these differences were not always significant. Tumor lipid peroxidation product levels were determined on the MDA-MB231 tumors; tumor lipid peroxidation levels were significantly (P less than 0.01) increased only in mice fed the fish oil diets. Supplementation of the fish oil diets with antioxidants (vitamin E + TBHQ) significantly reduced the level of tumor peroxidation products and significantly increased tumor volume (P less than 0.05). When tumor lipid peroxidation product levels in the fish oil plus antioxidant fed mice were reduced to the level of that observed in the tumors of the corn oil fed mice, no significant differences in tumor volumes were observed in these two groups. In contrast, supplementation of the fish oil diets with ferric citrate, significantly (P less than 0.05) increased tumor lipid peroxidation product levels and decreased tumor volume. Thus, the type of dietary fat can clearly affect the growth of human breast carcinomas (MCF-7 and MDA-MB231) maintained in athymic nude mice.(ABSTRACT TRUNCATED AT 400 WORDS)     

不同病理亚型乳腺癌脑转移患者预后分析

目的:了解不同病理亚型乳腺癌脑转移患者的预后特点。方法:根据肿瘤组织免疫组化ER、PR、HER-2 的表达情况将89例患者分为4 组:Luminal A型（ER+ 和/或PR+ ,HER-2-）17例、Luminal B型（ER+ 和/或PR+ ,HER-2 +）15例、HER-2 + 型（ER- ,PR- ,HER-2 +）24例和Basal-like型（ER- ,PR- ,HER-2-）33例。主要观察4 组患者分布比例、发病年龄、月经状态、病理类型、病理分级、肿瘤大小、淋巴结状态及脑转移发生距手术时间及部位等。使用SPSS15.0 统计软件进行数据分析,定量资料采用t检验,计数资料比较采用卡方检验,生存率计算采用Kaplan-Meier 法并用Log-rank 检验,P<0.05为差异有统计学意义。结果:所有患者当中Basal-like型所占比例最高（37.1%）,其次为HER-2 +（27%）,Luminal A型（19.1%）,Luminal B型最少（16.9%）。 Basal-like 型患者预后最差,其病理分级Ⅲ级的患者比例达到了73% 。在其他部位出现转移情况上,Luminal型患者表现出较高的骨转移倾向。全组患者的中位生存期为47个月,无病生存期为20个月,确诊脑转移后的生存期为9 个月。ER（-）且PR（-）较ER/PR（+）（45个月vs.52个月,P=0.006）、HER-2（+）较HER-2（-）（45个月vs.51.5 个月,P=0.04）、Basal-like亚型的患者预后较其他亚型差（33个月vs.52个月,P=0.000）。 结论:病理亚型是判断乳腺癌脑转移患者预后不同的良好指标,ER（-）且PR（-）、HER-2（+）、Basal-like亚型患者容易出现脑转移且预后较差。      

ER-α30和ER-α36在乳腺癌组织的表达及意义

目的探讨新型雌激素受体亚型ER-α30和ER-α36在乳腺癌中的表达及与他莫昔芬治疗预后的关系。方法收集2015年1月至2015年11月间在河北北方学院附属第一医院接受他莫昔芬内分泌治疗的Luminal A型乳腺癌患者75例,并收集同时期30例ER(-)乳腺癌患者组织。采用免疫组化染色SP法检测ER-α30和ER-α36蛋白表达。分析ER-α30和ER-α36蛋白表达与Luminal A型乳腺癌临床病理特征的关系。随访患者的无病生存时间(DFS)。采用Cox风险比例回归模型分析影响DFS的因素。结果Luminal A型乳腺癌组织中ER-α30蛋白阳性表达率为32.0%(24/75),低于ER(-)乳腺癌组织(P<0.05)。ER-α30蛋白表达与TNM分期、肿瘤直径、浸润深度、淋巴结转移、孕激素受体状态有关(P<0.05)。ER-α36蛋白阳性表达率为52.0%(39/75),与ER(-)乳腺癌组织比较差异无统计学意义(P>0.05)。ER-α36蛋白表达与TNM分期和肿瘤直径有关(P<0.05)。随访时间为11~54个月,患者48个月无病生存率为64.0%(48/75)。ER-α30阳性患者48个月无病生存率为33.33%(8/24),阴性患者为78.43%(40/51),差异具有统计学意义(P=0.001)。ER-α36阳性患者48个月无病生存率为48.7%(19/39),阴性患者为80.6%(29/36),差异具有统计学意义(P=0.002)。Cox风险比例回归分析显示,ER-α30、ER-α36是影响Luminal A型乳腺癌患者DFS的独立预后因素(P<0.05)。结论Luminal A型乳腺癌ER-α30和ER-α36阳性表达者接受他莫昔芬治疗无病生存期较短,其有望成为预测他莫昔芬治疗反应性的重要指标。     

The estrogen receptor negative-progesterone receptor positive breast carcinoma is a biological entity and not a technical artifact

The ER-/PR+ breast tumor may be the result of a false ER negative result. The aim of this study was to investigate whether there is a difference in patient and tumor characteristics of the ER-/PR+ phenotype in an Asian setting. A total of 2629 breast cancer patients were categorized on the basis of their age, ethnicity, tumor hormonal receptor phenotype, grade and histological type. There were 1230 (46.8%) ER+/PR+, 306 (11.6%) ER+/PR-, 122 (4.6%) ER-/PR+ and 972 (37%) ER-/PR-. ER-/PR+ tumors were 2.5 times more likely to be younger than 50 years at diagnosis (OR: 2.52; 95% CI: 1.72-3.67). Compared to ER+/PR+ tumors, the ER-/ PR+ phenotype was twice more likely to be associated with grade 3 tumors (OR:2.02; 95%CI: 1.00-4.10). In contrast, compared to ER-/PR- tumors, the ER-/PR+ phenotype was 90% less likely to be associated with a grade 3 tumor (OR: 0.12; 95%CI:0.05-0.26), and more likely to have invasive lobular than invasive ductal histology (OR: 3.66; 95%CI: 1.47-9.11). These results show that the ER-/PR+ phenotype occurs in a younger age group and is associated with intermediate histopathological characteristics compared to ER+/PR+ and ER-/PR- tumors. This may imply that it is a distinct entity and not a technical artifact.     

Changes of steroid hormone receptor content by chemotherapy and/or endocrine therapy in advanced breast cancer

In several sequences during the progression of cancer, the authors assayed estrogen receptors(ER) in 940 breast cancers and progesterone receptors(PgR) in 773 cancers. The percentages of ER+ and PgR+ cancers diminished according to the progression of malignancy. Sequential assays of ER and PgR were carried out in primary tumors and in the metastatic tumors at the first recurrence in 42 patients. During the disease-free interval, 10 (37%) of 27 ER+ tumors changed to ER- and all 15 ER- tumors remained negative. The hormone receptors were assayed before the treatments and after the tumor relapsed following regression or after the progression of cancer. The change of ER and PgR in 99 patients with advanced breast cancer were studied according to the type of systemic treatments. Through endocrine therapy, marked changes from ER+ to ER-, were noted (by antiestrogens, 47% [7/15]; by adreno-oophorectomy, 61% [11/18]). Almost no breast cancers changed from ER- to Er+ during the endocrine therapy (by antiestrogen, 1/6; by adreno-oophorectomy, 0/10). All of six PgR+ tumors changed to PgR- after therapy. By chemotherapy treatment, 44% (4/9) ER+ cancers became ER-, while 19% (3/16) ER- tumors changed to ER+. After the simultaneous combination of chemotherapy and endocrine therapy, 67% (10/15) of ER+ cancers changed to ER-, and 20% (2/10) of ER- tumors changed to ER+. Through the intervention of more than two kinds of chemotherapy and/or endocrine therapy between the first treatment and the last therapy, 79% (19/24) ER+ breast cancers changed to ER-. Thus, ER and PgR contents of breast cancer gradually became negative as the malignancy progressed, and with some kinds of treatments particularly including endocrine therapy. The significance of changes in hormone receptors after therapy was discussed.     

The combined effects of celecoxib and minocycline hydrochloride on inhibiting the osseous metastasis of breast cancer in nude mice

Breast carcinomas show a trend toward bone metastasis that is prevalent worldwide. Celecoxib (CX) and minocycline hydrochloride (MH) have both been widely used in treating breast cancer; however, their combined effects on the osseous metastasis of breast cancer have not yet been studied. In the present study, breast cancer cells were injected into the back of the femoral bone of nude mice, and CX and MH were intraperitoneally administered every other day at doses of 30 and 40 mg/kg/day, respectively, for 30 days. Tumor weights and volumes were significantly lower and the tumor inhibition rate was significantly higher in the CX + MH group than those of the control and CX or MH alone groups (p < 0.05). The cell density in the tumor tissue was significantly decreased and apoptotic and necrotic cell death was significantly increased in the CX + MH group, as compared with those of the control and CX or MH alone groups. Microvessel density and expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinase (MMP)-9 in the tumor tissues of the CX + MH group were significantly lower than those of the CX, MH, and control groups. The serum alkaline phosphatase level of the CX + MH group was significantly lower than those of the other groups (p < 0.01). These results suggest that a combined use of CX and MH has better inhibitory effects on the osseous metastasis of breast cancer, as compared to CX or MH alone. They exerted their combined effects by increasing tumor-cell death and decreasing the tumor expression of MMP-9 and VEGF systems.     

Folate intake and risk of breast cancer characterized by hormone receptor status.

Folate plays an important role in DNA methylation, and aberrant methylation of the estrogen receptor (ER) gene may be related to the loss of ER gene expression in breast tumors. Thus, deficient folate status has been hypothesized to be associated primarily with ER gene-negative breast tumors, but data relating folate intake to breast cancer risk according to ER status are sparse. We conducted a prospective cohort analysis of folate intake among 88,744 women in the Nurses' Health Study who completed a food frequency questionnaire in 1980 and every 2 to 4 years thereafter. During 20 years of follow-up, 2,812 ER+ and 985 ER- invasive breast cancer cases were documented. Higher total folate intake was significantly associated with lower risk of developing ER- but not ER+ breast cancer; the multivariable relative risks (RR) and 95% confidence intervals (95% CI) comparing the highest to the lowest quintile were 0.81 (0.66-0.99) for ER- tumors and 1.00 (0.89-1.14) for ER+ tumors. The inverse association between total folate intake and ER- breast cancer was mainly present among women consuming at least 15 g/d of alcohol (multivariable RR, 0.46; 95% CI,=0.25-0.86; top versus bottom quintile). These findings support the hypothesis that higher folate intake reduces the risk of developing ER- breast cancer. Ensuring adequate folate intake seems particularly important for women at higher risk of breast cancer because of alcohol consumption.     

Estrogen‐induced angiogenic factors derived from stromal and cancer cells are differently regulated by enterolactone and genistein in human breast cancer in vivo

Angiogenesis is a key in cancer progression and its regulators are released both by the tumor cells and the stroma. Dietary phytoestrogens, such as the lignan enterolactone (ENL) and the isoflavone genistein (GEN), may differently affect breast cancer growth. In this study, human breast cancer cells (MCF‐7) were established in mice creating a tumor with species‐specific cancer and stroma cells. Ovariectomized athymic mice supplemented with estradiol (E2) were fed basal AIN‐93G diet (BD) or BD supplemented with 100 mg/kg ENL, 100 mg/kg GEN or their combination (ENL+GEN). We show that ENL and ENL+GEN inhibited E2‐induced cancer growth and angiogenesis, whereas GEN alone did not. Microdialysis was used to sample extracellular proteins in tumors in vivo. ENL and ENL+GEN decreased both stroma‐ and cancer cell‐derived VEGF, whereas cancer cell‐derived PlGF increased. In subcutaneous Matrigel plugs in mice, ENL and ENL+GEN decreased E2‐induced endothelial cell infiltration, whereas GEN alone did not. In endothelial cells, ENL inhibited E2‐induced VEGFR‐2 expression, whereas GEN did not. These results suggest that ENL has potent effects on breast cancer growth, even in combination with GEN, by downregulating E2‐stimulated angiogenic factors derived both from the stroma and the cancer cells, whereas dietary GEN does not possess any antiestrogenic effects.     

BreastDefend™ prevents breast-to-lung cancer metastases in an orthotopic animal model of triple-negative human breast cancer

We have recently demonstrated that a natural dietary supplement BreastDefend (BD), which contains extracts from medicinal mushrooms (Coriolus versicolor, Ganoderma lucidum, Phellinus linteus), medicinal herbs (Scutellaria barbata, Astragalus membranaceus, Curcuma longa), and purified biologically active nutritional compounds (diindolylmethane and quercetin), inhibits proliferation and metastatic behavior of MDA-MB-231 invasive human breast cancer cells in vitro. In the present study, we evaluated whether BD suppresses growth and breast-to lung cancer metastasis in an orthotopic model of human breast cancer cells implanted in mice. Oral application of BD (100 mg/kg of body weight for 4 weeks) by intragastric gavage did not affect body weight or activity of liver enzymes and did not show any sign of toxicity in liver, spleen, kidney, lung and heart tissues in mice. Moreover, BD significantly decreased the change in tumor volume over time compared to the control group (p=0.002). BD treatment also markedly decreased the incidence of breast-to-lung cancer metastasis from 67% (control) to 20% (BD) (p<0.05) and the number of metastases from 2.8 (0.0, 48.0) in the control group to 0.0 (0.0, 14.2) in the BD treatment group (p<0.05). Finally, anti-metastatic activity of BD in vivo was further confirmed by the downregulation of expression of PLAU (urokinase plasminogen activator, uPA) and CXCR4 (C-X-C chemokine receptor-4) genes in breast tumors. In conclusion, BD may be considered as a biological therapeutic agent against invasive breast cancers.     

Serum enterolactone and postmenopausal breast cancer risk by estrogen, progesterone and herceptin 2 receptor status

Lignans are a group of estrogenic compounds present in plants. Several epidemiological studies proposed that lignans may protect against breast cancer by exerting anticarcinogenic activity. Levels of enterolactone were determined in serum samples of 1,250 cases and 2,164 controls from a large population-based case-control study. We assessed the association between serum enterolactone and postmenopausal breast cancer risk using conditional logistic regression accounting for potential risk and confounding factors. Fractional polynomials were used to determine the function that best fitted the data. Moreover, we assessed heterogeneity by estrogen/progesterone/herceptin (ER/PR/HER2) status of the tumor. Additionally, a meta-analysis with seven further studies addressing enterolactone concentrations and breast cancer risk was performed. Postmenopausal breast cancer risk decreased with increasing serum enterolactone levels [highest compared to lowest quintile: [odds ratio = 0.65; 95% confidence interval (CI) 0.52-0.83, p(trend) = < 0.0001]. A significant inverse association for ER+/PR+ as well as ER-/PR- tumors was observed, with a significantly stronger association for ER-/PR- tumors (p(heterogeneity) = 0.03). The association for ER-/PR- tumors did not differ by expression of HER2 (p(heterogeneity) = 0.3). The meta-analysis yielded a significant reduced pooled risk estimate of: 0.66; 95% CI: 0.55-0.77) comparing the highest to the lowest quantiles of enterolactone levels. We found strong evidence for a significant inverse association between serum enterolactone and postmenopausal breast cancer risk, which was stronger for ER-PR- than for ER+PR+ tumors but not differential by further expression of HER2. The overall evidence together with other studies supports an inverse association between higher serum enterolactone levels and postmenopausal breast cancer risk.     

In vitro effects on proliferation, apoptosis and colony inhibition in ER-dependent and ER-independent human breast cancer cells by selected mushroom species

Breast cancer is the most commonly diagnosed cancer among women in Western countries. Currently, there is no effective therapy for malignant estrogen-independent breast cancer. We have screened 38 species of edible mushroom on human estrogen-receptor positive (MCF-7) and estrogen-receptor negative (MDA-MB-231, BT-20) breast cancer cells to select potential agents with broad-spectrum antitumor activity against breast cancer cells. Water-based extracts of three mushroom species, Coprinellus sp., Coprinus comatus, Flammulina velutipes (CME, CCE and FVE, respectively), were identified as novel anti-breast cancer agents. The anti-tumor activities include: 1) marked growth inhibition of both ER+ and ER- breast cancer cells; 2) induction of rapid apoptosis on both ER+ and ER- cells; 3) significant inhibition of MCF-7 tumor colony formation in vitro. The antiproliferative and cytotoxic activities of the three mushroom extracts were dose-dependent, regardless of the hormone receptor status of the cancer cells. The degree of produced cytotoxicity on ER- breast cancer cells was very high, while the IC50 of mushroom extract CME was found to be as low as 40 microg/ml on MDA-MB-231 cells and the IC50 of mushroom extract FVE was only 30 microg/ml on BT-20 cells. More interestingly, mushroom extracts CME and FVE induced an exceptionally rapid apoptosis on MCF-7 and MDA-MB-231 detected by Annexin V-FITC within 2 h of treatment and DNA fragment end-labeling assay (TUNEL) in 5 h of treatment. Anchorage-independent growth assays indicated that the MCF-7 tumor colony formation rate was reduced by 60% in CCE- and CME-treated cells and nearly completely inhibited (99%) by FVE treatment. These results suggest that mushroom species Coprinus comatus, Coprinellus sp. and Flammulina velutipes contain potent antitumor compounds for breast cancer. Our finding is important due to the lack of chemotherapeutic and chemopreventive agents for ER- human breast cancer.     

高脂饮食对结肠癌肝脏转移的影响及作用机制

目的 探讨高脂饮食对结肠癌肝脏转移的影响及其作用机制。方法 30只NSI第三代免疫缺陷裸鼠脾脏种植结肠癌细胞DLD1构建移植瘤裸鼠模型,分别喂养普通饲料（对照组）、高脂饲料（高脂饮食组）和高脂饲料并腹腔注射CXCR4拮抗剂AMD3100（高脂饮食+AMD3100组）,每组10只。12周后颈椎脱臼处死,称量各组裸鼠体重、肝脏重量,统计肝脏中肿瘤转移灶数目,并采用Western blot和RT-qPCR检测肿瘤组织中SDF-1、CXCR4的蛋白和mRNA表达水平。结果 12周后,高脂饮食组裸鼠体重、脂肪重量、肝脏重量及血清瘦素浓度高于对照组和高脂饮食+AMD3100组（P<0.05）。对照组、高脂饮食组和高脂饮食+AMD3100组裸鼠发生肝脏转移的比例分别为30.0%、80.0%和40.0%。高脂饮食组裸鼠的肿瘤体积及肝脏转移灶数量均明显高于对照组［（3.83±0.42） mm³  vs （1.00±0.15） mm³,P<0.001;（4.33±0.58） 个 vs （1.33±0.58） 个,P=0.002］和高脂饮食+AMD3100组 ［（3.83±0.42） mm³  vs （1.96±0.15） mm³,P<0.001;（4.33±0.58） 个 vs （2.33±0.58） 个,P=0.002］。Western blot和RT-qPCR检测结果显示,高脂饮食组结肠癌组织中的SDF-1、CXCR4的蛋白和mRNA表达水平均较对照组和高脂饮食+AMD3100组明显上调（均P<0.05）。结论 高脂饮食可通过促进结肠癌癌组织中SDF-1和CXCR4的表达水平而增强结肠癌的肝脏定向转移。