Regulation of estrogen receptors α and β in human breast carcinoma by exogenous leptin in nude mouse xenograft model

Background It is essential to clarify the interactions of hormones during the progression of human breast cancer. This study examined the effects of exogenous human leptin on estrogen receptor （ER） α and β in human breast tumor tissue in a nude mouse xenograft model. Methods We created nude mice xenografts of MCF-7 human breast cancer cells, and randomly divided them into an experimental group and a control group. The mice in experimental group were injected subcutaneously around tumors with human leptin, while the control group were injected with the same dose of normal saline. A real-time RT-PCR assay was developed to quantify the mRNA of ERα, β in the tumor tissues. Western blotting analyses were used to assess the relative quantities of the ERα , β proteins. Results Leptin-treated xenografted nude mice were successfully established. The amount of ERa mRNA was significantly higher in the leptin group than in the control group （P 〈0.01）, while the amount of ERβ mRNA was significantly lower in the leptin group than in the control group （P 〈0.01）. Western blotting analyses revealed that the ERa protein level was significantly higher in the leptin group than in the control group （P 〈0.01）, while the ERβ protein level was significantly lower in the leptin group than in the control group （P 〈0.01）. Conclusions Nude mouse xenograft model can be safely and serviceably treated with human leptin by subcutaneous injections around tumor. ERα, β were both targets of leptin in breast cancer. Leptin can up-regulate the expression of ERa and down-regulate the expression of the ERβ in human breast tumor.

Lentivirus-mediated RNA interference targeting the ObR gene in human breast cancer MCF-7 cells in a nude mouse xenograft model

Background There is a significant association between obesity and breast cancer, which is possibly due to the expression of leptin. Therefore, it is important to clarify the role of leptin/ObR （leptin receptor） signaling during the progression of human breast cancer. Methods Nude mice with xenografts of MCF-7 human breast cancer cells were administered recombinant human leptin subcutaneous via injection around the tumor site. Mice in the experimental group were intratumorally injected with ObR-RNAi-lentivirus, while negative control group mice were injected with the same dose of negative-lentivirus. Tumor size was blindly measured every other day, and mRNA and protein expression levels of ObR, estrogen receptor a （ERa）, and vascular endothelial growth factor （VEGF） for each group were determined.Results Knockdown of ObR-treated xenografted nude mice with a high leptin microenvironment was successfully established. Local injection of ObR-RNAi-lentivirus significantly suppressed the established tumor growth in nude mice. ObR level was significantly lower in the experimental group than in the negative control group, while the amounts of ERα and VEGF expression were significantly lower in the leptin group than in the control group （P 〈0.01 for all）.Conclusions Inhibition of leptin/ObR signaling is essential to breast cancer proliferation and possible crosstalk between ObR and ERa, and VEGF, and may lead to novel therapeutic treatments aiming at targeting ObR in breast cancers.

Overexpression of leptin and leptin receptors in breast cancer positively correlates with clinicopathological features

Obesity has been reported to increase postmenopausal breast cancer risk by 30% to 50%, and obese breast cancer patients have been shown to present more aggressive breast cancer pathological features As most breast cancers are sex hormone-dependent, adipocytokines derived from adipose tissue, such as leptin, may account for the positive association between obesity and breast cancer. Leptin, a 16-kDa protein product of the obese gene, was initially regarded as a neuroendocrine factor in the hypothalamus to maintain homeostasis of body weight by regulating food intake and energy expenditure.

Clinical significance of PHPT1 protein expression in lung cancer

Background In our previous studies, we found the expression of 14-kD phosphohistidine phosphatase （PHPT1） was associated with lung cancer cells migration and invasion, and PHPT1 mRNA expression level in lung cancer tissues clinically correlated with lymph node metastasis. In the present study, we aimed to further investigate the expression of PHPT1 protein in lung cancer. Methods Expression of PHPT1 protein in tissue samples from 146 lung cancers and 30 normal tissues adjacent to lung cancers was assessed using immunohistochemical method. Fisher＇s exact test was used to analyze expression patterns of PHPT1 protein in these tissue types. Meanwhile, we studied the correlation between expression of PHPT1 protein and clinicopathological features in lung cancer. Results Significantly higher expression levels of PHPT1 protein were found in lung cancer samples （53.42%） than in normal tissues adjacent to lung cancer （23.33%） （P=0.003）. Fisher＇s exact test showed that lung cancer stage positively correlated with expression of PHPT1 protein （P=-0.02）, and lung cancer samples with lymph node metastasis showed higher PHPT1 protein expression （P=-0.016） than the samples without lymph node metastasis. Conclusions The results of this study agree with findings from our previous study of PHPT1 mRNA expression in lung cancer tissues, and strongly suggest that PHPT1 protein is closely associated with the carcinogenesis and metastasis of lung cancer. Thus, therapy targeting PHPT1 （inhibition or silencing） could be potentially benefited for lung cancer patients.

Effects of exogenous human leptin on heat shock protein 70 expression in MCF-7 breast cancer cells and breast carcinoma of nude mice xenograft model

Background It is important to identify the multiple sites of leptin activity in obese women with breast cancer.In this study,we examined the effect of exogenous human leptin on heat shock protein 70 （HSP70） expression in MCF-7 human breast cancer cells and in a breast carcinoma xenograft model of nude mice.Methods We cultured MCF-7 human breast cancer cells and established nude mice bearing xenograffs of these cells,and randomly divided them into experimental and control groups.The experimental group was treated with human leptin,while the control group was treated with the same volume of normal saline.A real-time reverse transcriptase-polymerase chain reaction （RT-PCR） assay was developed to quantify the mRNA expression of HSP70 in the MCF-7 human breast cancer cells and in tumor tissues.Western blotting analysis was applied to quantify the protein expression of HSP70 in the MCF-7 cells.Immunohistochemical staining was done to assess the positive rate of HSP70 expression in the tumor tissues.Results Leptin activated HSP70 in a dose-dependent manner in vitro：leptin upregulated significantly the expression of HSP70 at mRNA and protein levels in MCF-7 human breast cancer cells （P 〈0.001）.There was no significant difference in expression of HSP70 mRNA in the implanted tumors between the leptin-treated group and the control group （P〉0.05）.Immunohistochemical staining revealed no significant difference in tumor HSP70 expression between the leptin-treated group and the control group （P〉0.05）.Conclusions A nude mouse xenograft model can be safely and efficiently treated with human leptin by subcutaneous injections around the tumor.HSP70 may be target of leptin in breast cancer.Leptin can significantly upregulate the expression of HSP70 in a dose-dependent manner in vitro.

超声引导下坐骨神经联合股神经阻滞用于足踝部手术的临床观察

目的探讨超声引导下坐骨神经阻滞联合股神经阻滞用于足踝部手术的临床效果。方法选择2018年2月—2019年7月在我院行手术治疗的95例足踝部手术的患者,采用随机数表法分为对照组(n=47)和观察组(n=48)。对照组采用腰硬联合麻醉,观察组采用超声引导下的坐骨神经联合股神经阻滞,对比两组麻醉前(T0)、手术开始时(T_(1))、手术开始后30 min(T_(2))、手术结束时(T_(3))患者的血流动力学[心率(HR)、舒张压(DBP)、收缩压(SBP)、血氧饱和度(SpO2)]、镇痛效果(VAS)。结果两组患者T0的HR、DBP水平差异无统计学意义(t=0.707,P=0.481;t=0.676,P=0.501),观察组T_(1)的HR、DBP水平均高于对照组,差异有统计学意义(t=6.480,P<0.001;t=2.758,P=0.007);两组患者T0SBP水平差异无统计学意义(t=0.316,P=0.753),观察组T_(1)、T_(2)、T_(3)的SBP水平均高于对照组,差异有统计学意义(t=3.496,P=0.001;t=2.708,P<0.001;t=5.182,P<0.001);两组患者各个时间段的SpO2水平差异无统计学意义(t=0.774、1.790、1.915、1.908,P>0.05);观察组术后1 h、12 h、24 h VAS评分均低于对照组,差异有统计学意义(t=5.037,6.843,6.442,P<0.05)。结论超声引导下坐骨神经阻滞联合股神经阻滞用于足踝部手术效果满意,术中对血流动力学影响小,术后镇痛时间长。