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61.
Na+/H+ exchanger regulatory factor 1 (NHERF1) is a scaffold protein known to interact with a number of cancer-related proteins. nherf1 Mutations (K172N and D301V) were recently identified in breast cancer cells. To investigate the functional properties of NHERF1, wild-type and cancer-derived nherf1 mutations were stably expressed in SKMES-1 cells respectively. NHERF1-wt overexpression suppressed the cellular malignant phenotypes, including proliferation, migration, and invasion. nherf1 Mutations (K172N and D301V) caused complete or partial loss of NHERF1 functions by affecting the PTEN/NHERF1/PDGFRβ complex formation, inactivating NHERF1 inhibition of PDGF-induced AKT and ERK activation, and attenuating the tumor-suppressor effects of NHERF1-wt. These results further demonstrated the functional consequences of breast cancer-derived nherf1 mutations (K172N and D301V), and suggested the causal role of NHERF1 in tumor development and progression.  相似文献   
62.
Three novel steroidal antiestrogen–geldanamycin conjugates were prepared using a convergent strategy. The antiestrogenic component utilized the 11β-(4-functionalized-oxyphenyl) estradiol scaffold, while the geldanamycin component was derived by replacement of the 17-methoxy group with an appropriately functionalized amine. Ligation was achieved in high yield using azide alkyne cyclization reactions. Evaluation of the products against two breast cancer cell lines indicated that the conjugates retained significant antiproliferative activity.  相似文献   
63.
We first report the application of 3-acyl-5-hydroxybenzofurans as a scaffold to develop potential drugs for breast cancer. Seven novel derivative compounds were synthesized by using a microwave-assisted synthesis method. Those compounds exhibited different antiproliferation against human breast cancer MCF-7 cells, with the best activity of IC50 = 43.08 μM for compound 1. A Quantum Mechanics Polarized Ligand Docking (QPLD) study was carried out to investigate the binding interactions between these compounds and estrogen receptor alpha (ERα). The simulation results showed that the trend of receptor–ligand binding interactions was same as that of their antiproliferative activities. A detailed analysis indicated that compound 1 possesses the highest Van der Waals and hydrogen bond interactions compared to the other six compounds and better inhibitors are achievable by enhancing the hydrogen bond interactions. Based on these results, we addressed that 3-acyl-5-hydroxybenzofuran is an attractive scaffold for designing drugs against breast cancer.  相似文献   
64.
The aetiology of breast cancer is multifactorial. While there are known genetic predispositions to the disease it is probable that environmental factors are also involved. Recent research has demonstrated a regionally specific distribution of aluminium in breast tissue mastectomies while other work has suggested mechanisms whereby breast tissue aluminium might contribute towards the aetiology of breast cancer. We have looked to develop microwave digestion combined with a new form of graphite furnace atomic absorption spectrometry as a precise, accurate and reproducible method for the measurement of aluminium in breast tissue biopsies. We have used this method to test the thesis that there is a regional distribution of aluminium across the breast in women with breast cancer. Microwave digestion of whole breast tissue samples resulted in clear homogenous digests perfectly suitable for the determination of aluminium by graphite furnace atomic absorption spectrometry. The instrument detection limit for the method was 0.48 μg/L. Method blanks were used to estimate background levels of contamination of 14.80 μg/L. The mean concentration of aluminium across all tissues was 0.39 μg Al/g tissue dry wt. There were no statistically significant regionally specific differences in the content of aluminium. We have developed a robust method for the precise and accurate measurement of aluminium in human breast tissue. There are very few such data currently available in the scientific literature and they will add substantially to our understanding of any putative role of aluminium in breast cancer. While we did not observe any statistically significant differences in aluminium content across the breast it has to be emphasised that herein we measured whole breast tissue and not defatted tissue where such a distribution was previously noted. We are very confident that the method developed herein could now be used to provide accurate and reproducible data on the aluminium content in defatted tissue and oil from such tissues and thereby contribute towards our knowledge on aluminium and any role in breast cancer.  相似文献   
65.
目的:探讨自动乳腺全容积扫描(automated breast volume scanner,ABVS)联合乳腺钼靶摄影在乳腺疾病诊断中的价值。方法:观察随访130例就诊我科的乳腺疾病患者,进行ABVS、传统超声和乳腺钼靶检查。结果:130例患者中ABVS的疾病单独诊断准确率为91.5%(119/130),传统乳腺超声的单独诊断准确率为84.6%(110/130),乳腺钼靶的单独诊断准确率为86.9%(113/130),而ABVS联合乳腺钼靶应用的诊断准确率为95.4%(124/130),明显优于两者单独应用,差异具有统计学意义(P〈0.05)。结论:ABVS是一种全新的乳腺检查方法,较传统乳腺超声、乳腺钼靶具有较高的疾病诊断准确率,而ABVS联合乳腺钼靶可以显著提高诊断的准确率,值得在临床推广。  相似文献   
66.
目的:探讨中国北方地区血清钙、维生素D水平与乳腺癌及相关临床因素的关系.方法:选取2007年12月至2012年7月哈尔滨医科大学附属肿瘤医院794例女性乳腺癌患者及976例乳腺良性肿瘤患者,并以128例健康妇女为对照,取空腹血清采用原子吸收分光光度法检测三组血清钙含量,采用放免法检测三组中162例血清25(OH)D含量,结合相关临床资料进行分析.结果:乳腺癌组血清钙含量为2.26± 0.12 mmol/L,乳腺良性肿瘤组血清钙含量为2.26±0.09 mmol/L,正常对照组血清钙含量为2.25±0.24 mmol/L,经方差分析,三组总体均数差别无统计学意义(P>0.05);乳腺癌患者的血清钙水平与年龄、TNM分期、BMI、绝经情况、乳腺癌家族遗传史无关(P>0.05).乳腺癌组血清25(OH)D含量为41.91±7.55 ng/mL,乳腺良性肿瘤血清25(OH)D含量为54.62±7.48 ng/mL,正常对照组血清25(OH)D含量为56.15±8.87 ng/mL,经方差分析,乳腺癌患者血清25(OH)D含量低于乳腺良性肿瘤组,差别有统计学意义(P<0.05),乳腺良性肿瘤组与正常对照组差别无统计学意义(P>0.05);乳腺癌患者的维生素D水平与年龄、TNM分期、BMI、绝经情况有关(P<0.05),而与乳腺癌家族遗传史无关(P>0.05).结论:中国北方地区的乳腺癌患者血清钙水平与乳腺良性肿瘤患者无明显差异.乳腺癌患者的维生素D水平低于乳腺良性肿瘤患者,并且与年龄、TNM分期、BMI、绝经情况有关.维生素D水平降低可能与乳腺癌的发生有关,高水平的维生素D可能会降低女性患乳癌的风险.  相似文献   
67.
本文对双磷酸盐、狄诺塞麦、Sagopilone等特异性靶向药物在乳腺癌骨转移靶向治疗中的作用机制、临床应用、临床疗效等方面的相关研究进展情况进行了简要阐述。双磷酸盐在抑制骨转移和非骨转移中发挥作用,狄诺塞麦可能成为双磷酸盐的合理替代物,尤其在双磷酸盐治疗效果不佳的病人中,而新型抗癌药物Sagopilone、骨唾液酸蛋白抑制剂亦可通过多种机制参与乳腺癌转移过程,具有抑制骨转移的巨大潜力。  相似文献   
68.
Circadian (clock) genes have been linked with several functions relevant to cancer, and epidemiologic research has suggested relationships with breast cancer risk for variants in NPAS2, CLOCK, CRY2 and TIMELESS. Increased breast cancer risk has also been observed among shift workers, suggesting potential interactions in relationships of circadian genes with breast cancer. Relationships with breast cancer of 100 SNPs in 14 clock-related genes, as well as potential interactions with shift work history, were investigated in a case–control study (1042 cases, 1051 controls). Odds ratios in an additive genetic model for European-ancestry participants (645 cases, 806 controls) were calculated, using a two-step correction for multiple testing: within each gene through permutation testing (10,000 permutations), and correcting for the false discovery rate across genes. Interactions of genotypes with ethnicity and shift work (<2 years vs ≥2 years) were evaluated individually. Following permutation analysis, two SNPs (rs3816360 in ARNTL and rs11113179 in CRY1) displayed significant associations with breast cancer and one SNP (rs3027188 in PER1) was marginally significant; however, none were significant following adjustment for the false discovery rate. No significant interaction with shift work history was detected. If shift work causes circadian disruption, this was not reflected in associations between clock gene variants and breast cancer risk in this study. Larger studies are needed to assess interactions with longer durations (>30 years) of shift work that have been associated with breast cancer.  相似文献   
69.
Background: The association between antihypertensive medications and survival in cancer patients remains unclear. Objectives: To explore the association between classes of antihypertensive drugs and survival in cancer patients. Methods: Provincial Cancer Registry data was linked with a Provincial Drug Program Information Network (DPIN) for patients with lung (n = 4241), colorectal (n = 3967), breast (n = 4019) or prostate (n = 3355) cancer between the years of 2004 and 2008. Cox regression analyses were used to compare survival of patients using beta blockers (BBs), angiotensin-converting enzyme inhibitors/receptor blockers (ACEi/ARB), calcium channel blockers (CCBs) or thiazide diuretics (TDs) to survival of patients who did not use any of these antihypertensive drugs. Survival of patients using only one class of antihypertensive drugs were compared to each other, with BBs as the reference class. Results: Compared to the antihypertensive drug non-user cohort, BBs had no effect on survival for any of the cancers. ACEi/ARBs use was weakly associated with increased deaths for breast cancer (HR: 1.22, 95% CI: 1.04–1.44) and lung cancer (HR: 1.11, 95% CI: 1.03–1.21) patients. Deaths were also increased with CCB use in patients with breast cancer (HR: 1.22, 95% CI: 1.02–1.47) and with TD use in lung cancer patients (HR: 1.1, 95% CI: 1.01–1.19). There was strong evidence (p-value <0.0001) of an increase in deaths with TD use for colorectal (HR: 1.28, 95% CI: 1.15–1.42), and prostate (HR 1.41, 1.2–1.65) cancer patients. When including only antihypertensive drug users prescribed one drug class, lung cancer patients receiving CCBs had improved survival compared to BBs (HR 0.79, 95% CI: 0.64–0.98). Conclusions: Some classes of antihypertensive agents are associated with a decreased survival in certain cancers. The decrease could be due to more comorbidities in antihypertensive drug users. However, CCB use was associated with improved survival in lung cancer patients.  相似文献   
70.
紫杉醇虽被证明在多种肿瘤治疗中均具有良好的效果,但其有一个严重的缺陷:水溶性低。临床使用中需使用聚氧乙烯蓖麻油(CremphorEL)或无水乙醇作为溶剂,但其在体内降解时能释放组胺,导致严重的过敏反应以及肾毒性和神经毒性等不良反应,此外还存在患者耐受性差、血药浓度低、靶向性差等不足。在乳腺癌的诊断和治疗中,纳米技术改变了紫杉醇制剂的特征参数而使药物表现出缓释、控释性及靶向性等优势,解决了传统紫杉醇制剂水溶性差的缺点,提高了药物的生物利用度,并明显降低了紫杉醇的毒性和副作用,给紫杉醇药物在体内运输提供了新途径。  相似文献   
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