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Objective To explore the effects of arsenite on the expression of estrogen receptor (ER) mRNA,ER protein and the ER signaling pathway in rats.Methods Random grouping experiment design was used to evaluate the effects of arsenite on the expression of ER mRNA,ER protein and the ER signaling pathway (24 rats were divided into 4 groups:control,Aslow,Asmiddle,Ashigh groups;6 rats in each group).Female rats were exposed to NaAsO2 (0.625,2.500,10.000 mg/kg) by oral perfusion at gradient doses for three months respectively.The expression of ER mRNA as effect biomarker was observed through RT-PCR.The concentration of ER,vascular endothelial growth factor (VEGF),cyclin D1 (CYC-D1),and progesterone receptor (PR) in serum was determined as effect biomarkers using enzyme-linked immunosorbent assay (ELISA).Results The levels of ER mRNA,VEGF,PR,CYC-D1,and ER in control,Aslow,Asmiddle,and Ashigh groups were statistically different (F =204.13,227.14,256.13,179.23,167.34,all P ＜ 0.01).With increasing of arsenic,the expression of ER mRNA,VEGF,and PR gradually decreased (all P ＜ 0.01);the dose effect relationship was obvious;the expression of CYC-D1 and ER in Asmiddle [(25.45 ± 9.29) U/L,(22.16 ± 9.16) ng/L] was higher than that in Ashigh [(2.60 ± 0.23) U/L,(9.06 t 2.06) ng,/L,all P ＜ 0.01].Arsenic was negatively associated with ER mRNA,ER,VEGF,CYC-D1 and PR (r =-0.689,-0.515,-0.675,-0.456,-0.397,P ＜ 0.01 or ＜ 0.05).ER mRNA was positively associated with ER,VEGF,CYC-D1 and PR (r =0.894,0.662,0.713,0.699,P ＜ 0.01 or ＜ 0.05).Conclusions The expression of ER mRNA and ER protein are inhibited by arsenic,ER may be served as a sensitive biomarker of reproductive system damage after exposed to arsenic.The ER-VEGF,CYC-D1 and PR pathway participate in the process of reproductive system damage caused by arsenic.Arsenic is probably a environmental estrogen.
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OBJECTIVE: To establish a KDR high throughput screening model with homogeneous time resolved fluorescence(HTRF) detection technology in order to screen small molecular KDR inhibitors from the compound library. METHODS: A 20 μL assay system in 384-well low-volume white microplate was developed with HTRF based fluorescence detection system to determine the enzyme activity. The optimization steps consisted of the following experiments: enzyme concentration and incubation time optimiztion, ATP and substrate Km determination, quality control experiments including signal noise ratio inspection, the inhibitor SU5416 IC50 validation, and Z' value calculation. After a stable assay system was accomplished, a HTS campaign was started with 10560 samples irom the compound library and the IC50 of some compounds were determined. RESULTS: The optimized KDR activity assay conditions were as follows: the kinase concentration was 0.10 ng · μL-1; ATP Km was 0.75μmol · L-1; substrate Km was 94.90 nmol · L-1; biotin/ SA ratio was 2:1; Z' value was 0.85 and the IC50 of SU5416 inhibitor was 1.03 μmol · L-1. Three compounds with the ID of S2-14, S2-16, and S2-38 showed IC50 on KDR of 1.01 × 10-4, 6.04 × 10-5, 7.23 × 10-6 mol · L-1, respectively. CONCLUSION: A KDR high throughput screening model has been successfully established with HTRF methodology and a focused HTS campaign has been accomplished with several leads. This assay system is reliable and the results are stable. The established assay system is suitable for further application in screening natural anti-angiogenesis products.
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Objective: To study the relationship between human papillomavirus (HPV) infection and the expression of vascular endothelial growth factor receptor (VEGF) and epidermal growth factor (EGFR) in non small-cell lung cancer (NSCLC), and discuss their significance in the oncogenesis of lung cancer. Methods: The PCR method was used to detect the HPV infection in 89 cases of NSCLC and 20 cases of benign pulmonary lesions. The immunohistochemicl SP method was used to measure the expressions of VEGF and EGFR in HPV (+) and HPV (-) patients with NSCLC. Results: The infection rate of HPV in NSCLC group (35/89) was significantly higher than that in patients with benign pulmonary lesions (1/20, P = 0. 007). The expression of EGFR and VEGF in HPV (+) group was significantly higher than that in HPV (-) group (P < 0.01). The expression of VEGF had no significant difference between HPV(+), EGFR (+) group and HPV(+), EGFR(-) group. The HPV infection significantly correlated with the differentiation degree and lymphatic metastasis of NSCLC, but did not correlate with the histological type, smoking, sex, and age of patients. The expression of VEGF was associated with the lymphatic metastasis but not with other clinicopathologic parameters. The expression of EGFR had no relationship with clinicopathologic features. Conclusion: HPV infection has a significant correlation with the oncogenesis of NSCLC. The HPV infection stimulates lymphangiogenesis and facilitated lymphatic metastasis of lung cancer by inducing the expression of EGFR and VEGF. Prevention of HPV infection has important significance to decrease the occurrence and reduce early metastasis of lung cancer.
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Objective: To investigate the effects of estrogen and progesterone on the expression of vascular endothelial growth factor (VEGF) and its receptors (VEGFR) in mouse uterus. Methods: 3-week-old immature female mice were randomly divided into 7 groups and treated with corn oil, estradiol (E2) of 1.5, 3.0, 10, 25 ng, progesterone (P) of 100 ?g and (E_2 10 ng + P 100 ?g)/mouse, respectively. After the treatment for 48 h, mouse uterus was collected to isolate total RNA. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression of mRNA isoforms of VEGF and its receptors in mouse uterus. Results: Compared with control, both E_2 and P significantly increased the expression of VEGF164 and VEGF120 mRNA in mouse uterus. The expression of VEGFR2 mRNA, not VEGF1 mRNA, was decreased by E_2 treatment in a dose-independent manner. Conclusion: Both estradiol and progesterone up-regulated the expression of VEGF, but estradiol down-regulated the expression of VEGFR2 in mouse uterus.