Key Spec Table
|Species Reactivity||Key Applications||Host||Format||Antibody Type|
|H, M, R||WB, ICC, IH(P)||Rb||Culture Supernatant||Monoclonal Antibody|
|Presentation||Unpurified rabbit monoclonal IgG in buffer containing 50 mM Tris-Glycine (pH 7.4), 0.15 M NaCl, 40% Glycerol, 0.01% sodium azide and 0.05% BSA.|
|Safety Information according to GHS|
|Material Size||100 µL|
|Reference overview||Application||Pub Med ID|
|Alterations in ubiquitin ligase Siah-2 and its corepressor N-CoR after P-MAPA immunotherapy and anti-androgen therapy: new therapeutic opportunities for non-muscle invasive bladder cancer.|
Garcia, PV; Apolinário, LM; Böckelmann, PK; da Silva Nunes, I; Duran, N; Fávaro, WJ
International journal of clinical and experimental pathology 8 4427-43 2015
The present study describes the role of the ubiquitin ligase Siah-2 and corepressor N-CoR in controlling androgen receptor (AR) and estrogen receptors (ERα and ERβ) signaling in an appropriate animal model (Fischer 344 female rats) of non-muscle invasive bladder cancer (NMIBC), especially under conditions of anti-androgen therapy with flutamide. Furthermore, this study describes the mechanisms of a promising therapeutic alternative for NMIBC based on Protein aggregate magnesium-ammonium phospholinoleate-palmitoleate anhydride (P-MAPA) intravesical immunotherapy combined with flutamide, involving the interaction among steroid hormone receptors, their regulators and Toll-like receptors (TLRs). Our results demonstrated that increased Siah-2 and AR protein levels and decreased N-CoR, cytochrome P450 (CYP450) and estrogen receptors levels played a critical role in the urothelial carcinogenesis, probably leading to escape of urothelial cancer cells from immune system attack. P-MAPA immunotherapy led to distinct activation of innate immune system TLRs 2 and 4-mediated, resulting in increase of interferon signaling pathway, which was more effective in recovering the immunosuppressive tumor immune microenvironment and in recovering the bladder histology features than BCG (Bacillus Calmette-Guerin) treatments. The AR blockade therapy was important in the modulating of downstream molecules of TLR2 and TLR4 signaling pathway, decreasing the inflammatory cytokines signaling and enhancing the interferon signaling pathway when associated with P-MAPA. Taken together, the data obtained suggest that interferon signaling pathway activation and targeting AR and Siah-2 signals by P-MAPA intravesical immunotherapy alone and/ or in combination with AR blockade may provide novel therapeutic approaches for NMIBC.
|Folate Deficiency Could Restrain Decidual Angiogenesis in Pregnant Mice.|
Li, Y; Gao, R; Liu, X; Chen, X; Liao, X; Geng, Y; Ding, Y; Wang, Y; He, J
Nutrients 7 6425-45 2015
The mechanism of birth defects induced by folate deficiency was focused on mainly in fetal development. Little is known about the effect of folate deficiency on the maternal uterus, especially on decidual angiogenesis after implantation which establishes vessel networks to support embryo development. The aim of this study was to investigate the effects of folate deficiency on decidual angiogenesis. Serum folate levels were measured by electrochemiluminescence. The status of decidual angiogenesis was examined by cluster designation 34 (CD34) immunohistochemistry and the expression of angiogenic factors, including vascular endothelial growth factor A (VEGFA), placental growth factor (PLGF), and VEGF receptor 2 (VEGFR2) were also tested. Serum levels of homocysteine (Hcy), follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), progesterone (P4), and estradiol (E2) were detected by Enzyme-linked immunosorbent assay. The folate-deficient mice had a lower folate level and a higher Hcy level. Folate deficiency restrained decidual angiogenesis with significant abnormalities in vascular density and the enlargement and elongation of the vascular sinus. It also showed a reduction in the expressions of VEGFA, VEGFR2, and PLGF. In addition, the serum levels of P4, E2, LH, and PRL were reduced in folate-deficient mice, and the expression of progesterone receptor (PR) and estrogen receptor α (ERα) were abnormal. These results indicated that folate deficiency could impaire decidual angiogenesis and it may be related to the vasculotoxic properties of Hcy and the imbalance of the reproductive hormone.
|Tyrosine phosphatase Shp2 mediates the estrogen biological action in breast cancer via interaction with the estrogen extranuclear receptor.|
Li, J; Kang, Y; Wei, L; Liu, W; Tian, Y; Chen, B; Lin, X; Li, Y; Feng, GS; Lu, Z
PloS one 9 e102847 2014
The extranuclear estrogen receptor pathway opens up novel perspectives in many physiological and pathological processes, especially in breast carcinogenesis. However, its function and mechanisms are not fully understood. Herein we present data identifying Shp2, a SH2-containing tyrosine phosphatase, as a critical component of extranuclear ER pathway in breast cancer. The research checked that the effect of Shp2 on the tumor formation and growth in animal model and investigated the regulation of Shp2 on the bio-effect and signaling transduction of estrogen in breast cancer cell lines. The results showed that Shp2 was highly expressed in more than 60% of total 151 breast cancer cases. The inhibition of Shp2 activity by PHPS1 (a Shp2 inhibitor) delayed the development of dimethylbenz(a)anthracene (DMBA)-induced tumors in the rat mammary gland and also blocked tumor formation in MMTV-pyvt transgenic mice. Estradiol (E2) stimulated protein expression and phosphorylation of Shp2, and induced Shp2 binding to ERα and IGF-1R around the membrane to facilitate the phosphorylation of Erk and Akt in breast cancer cells MCF7. Shp2 was also involved in several biological effects of the extranuclear ER-initiated pathway in breast cancer cells. Specific inhibitors (phps1, phps4 and NSC87877) or small interference RNAs (siRNA) of Shp2 remarkably suppressed E2-induced gene transcription (Cyclin D1 and trefoil factor 1 (TFF1)), rapid DNA synthesis and late effects on cell growth. These results introduced a new mechanism for Shp2 oncogenic action and shed new light on extranuclear ER-initiated action in breast tumorigenesis by identifying a novel associated protein, Shp2, for extranuclear ER pathway, which might benefit the therapy of breast cancer.
|Sex-dependent differences in intestinal tumorigenesis induced in Apc1638N/+ mice by exposure to γ rays.|
Trani, D; Moon, BH; Kallakury, B; Hartmann, DP; Datta, K; Fornace, AJ
International journal of radiation oncology, biology, physics 85 223-9 2013
The purpose of the present study was to assess the effect of 1 and 5 Gy radiation doses and to investigate the interplay of gender and radiation with regard to intestinal tumorigenesis in an adenomatous polyposis coli (APC) mutant mouse model.Apc1638N/+ female and male mice were exposed whole body to either 1 Gy or 5 Gy of γ rays and euthanized when most of the treated mice became moribund. Small and large intestines were processed to determine tumor burden, distribution, and grade. Expression of proliferation marker Ki-67 and estrogen receptor (ER)-α were also assessed by immunohistochemistry.We observed that, with both 1 Gy and 5 Gy of γ rays, females displayed reduced susceptibility to radiation-induced intestinal tumorigenesis compared with males. As for radiation effect on small intestinal tumor progression, although no substantial differences were found in the relative frequency and degree of dysplasia of adenomas in irradiated animals compared with controls, invasive carcinomas were found in 1-Gy- and 5-Gy-irradiated animals. Radiation exposure was also shown to induce an increase in protein levels of proliferation marker Ki-67 and sex-hormone receptor ER-α in both non tumor mucosa and intestinal tumors from irradiated male mice.We observed important sex-dependent differences in susceptibility to radiation-induced intestinal tumorigenesis in Apc1638N/+ mutants. Furthermore, our data provide evidence that exposure to radiation doses as low as 1 Gy can induce a significant increase in intestinal tumor multiplicity as well as enhance tumor progression in vivo.
|Exposure to ionizing radiation causes long-term increase in serum estradiol and activation of PI3K-Akt signaling pathway in mouse mammary gland.|
Suman, S; Johnson, MD; Fornace, AJ; Datta, K
International journal of radiation oncology, biology, physics 84 500-7 2012
Exposure to ionizing radiation is an established risk factor for breast cancer. Radiation exposure during infancy, childhood, and adolescence confers the highest risk. Although radiation is a proven mammary carcinogen, it remains unclear where it acts in the complex multistage process of breast cancer development. In this study, we investigated the long-term pathophysiologic effects of ionizing radiation at a dose (2 Gy) relevant to fractionated radiotherapy.Adolescent (6-8 weeks old; n = 10) female C57BL/6J mice were exposed to 2 Gy total body γ-radiation, the mammary glands were surgically removed, and serum and urine samples were collected 2 and 12 months after exposure. Molecular pathways involving estrogen receptor-α (ERα) and phosphatidylinositol-3-OH kinase (PI3K)-Akt signaling were investigated by immunohistochemistry and Western blot.Serum estrogen and urinary levels of the oncogenic estrogen metabolite (16αOHE1) were significantly increased in irradiated animals. Immunostaining for the cellular proliferative marker Ki-67 and cyclin-D1 showed increased nuclear accumulation in sections of mammary glands from irradiated vs. control mice. Marked increase in p85α, a regulatory sub-unit of the PI3K was associated with increase in Akt, phospho-Akt, phospho-BAD, phospho-mTOR, and c-Myc in irradiated samples. Persistent increase in nuclear ERα in mammary tissues 2 and 12 months after radiation exposure was also observed.Taken together, our data not only support epidemiologic observations associating radiation and breast cancer but also, specify molecular events that could be involved in radiation-induced breast cancer.
|MGMT inhibition restores ERα functional sensitivity to antiestrogen therapy.|
Bobustuc, GC; Smith, JS; Maddipatla, S; Jeudy, S; Limaye, A; Isley, B; Caparas, ML; Constantino, SM; Shah, N; Baker, CH; Srivenugopal, KS; Baidas, S; Konduri, SD
Molecular medicine (Cambridge, Mass.) 18 913-29 2012
Antiestrogen therapy resistance remains a huge stumbling block in the treatment of breast cancer. We have found significant elevation of O(6) methylguanine DNA methyl transferase (MGMT) expression in a small sample of consecutive patients who have failed tamoxifen treatment. Here, we show that tamoxifen resistance is accompanied by upregulation of MGMT. Further we show that administration of the MGMT inhibitor, O(6)-benzylguanine (BG), at nontoxic doses, leads to restoration of a favorable estrogen receptor alpha (ERα) phosphorylation phenotype (high p-ERα Ser167/low p-ERα Ser118), which has been reported to correlate with sensitivity to endocrine therapy and improved survival. We also show BG to be a dual inhibitor of MGMT and ERα. In tamoxifen-resistant breast cancer cells, BG alone or in combination with antiestrogen (tamoxifen [TAM]/ICI 182,780 [fulvestrant, Faslodex]) therapy enhances p53 upregulated modulator of apoptosis (PUMA) expression, cytochrome C release and poly (ADP-ribose) polymerase (PARP) cleavage, all indicative of apoptosis. In addition, BG increases the expression of p21(cip1/waf1). We also show that BG, alone or in combination therapy, curtails the growth of tamoxifen-resistant breast cancer in vitro and in vivo. In tamoxifen-resistant MCF7 breast cancer xenografts, BG alone or in combination treatment causes significant delay in tumor growth. Immunohistochemistry confirms that BG increases p21(cip1/waf1) and p-ERα Ser167 expression and inhibits MGMT, ERα, p-ERα Ser118 and ki-67 expression. Collectively, our results suggest that MGMT inhibition leads to growth inhibition of tamoxifen-resistant breast cancer in vitro and in vivo and resensitizes tamoxifen-resistant breast cancer cells to antiestrogen therapy. These findings suggest that MGMT inhibition may provide a novel therapeutic strategy for overcoming antiestrogen resistance.