objectives colloidal drug delivery system, solid lipid nanoparticles (slns), helps to increase the solubility of the drug and its oral bioavailability. methods tamoxifen (tam) as a nonsteroidalantiestrogen drug was formulated in sln and an in vitro study was conducted to determine the cytotoxicity effect of tam-loaded slns on human breast cancer cell lines mcf-7 (estrogen receptor-positive) and...

An 8-mer peptide (EMTOVNOG) derived from alpha-fetoprotein was compared with tamoxifen for activity against growth of human breast cancer xenografts implanted in immune-deficient mice. Both peptide and tamoxifen prevented growth of estrogen-receptor-positive MCF-7 and T47D human breast cancer xenografts. A subline of MCF-7, made resistant to tamoxifen by a 6-month exposure to this drug in cultu...

Tamoxifen has been prescribed to millions of females for breast cancer prevention or treatment. However, tamoxifen is known to significantly enhance the risk of developing endometrial lesions, including hyperplasia, polyps, carcinomas, and sarcoma. Notably, tamoxifen-associated endometrial cancer often has a poor clinical outcome. Understanding the molecular mechanism of tamoxifen-induced endom...

lead, copper, cobalt, nickel, iron and zinc ions form monocitrate complexes (negative charge) in citrate solution which is absorbed on the citrate form of anion-exchange resins (citrate as counter ion) y exchange of citrate ion with citrate complexes. these are subsequently recovered from the resin by 0.5m ammonium citrate eluent at ph 2.0. under optimized conditions, quantitative recovery was ...

Tamoxifen has efficacy as a breast cancer therapy and chemoprevention agent. However, toxicity and resistance to tamoxifen limit its clinical application. There is an urgent need to develop compounds that may be combined with tamoxifen to improve efficacy and overcome toxicity and resistance. We showed previously that the organoselenium compound methylseleninic acid (MSA) increased the growth-i...

Background/Overview TAMOXIFEN METABOLISM Tamoxifen undergoes extensive primary and secondary metabolism, and plasma concentrations of tamoxifen and its metabolites vary widely. The metabolite 4-hydroxytamoxifen (4-OH tamoxifen) has demonstrated a 100-fold greater affinity for the estrogen receptor and 30to 100-fold greater potency in suppressing estrogen-dependent cell proliferation in vitro co...

Abstract Tamoxifen resistance remains a clinical problem in estrogen receptor (ER)-positive breast cancer. SUMOylation of ER? enhances ER?-induced transcription activity. Tripartite motif-containing (TRIM) proteins are new class SUMO E3 ligases, which regulate the proteins. However, precise molecular mechanism and function TRIM3 response to tamoxifen remain unclear. In present study, we observe...

Tamoxifen is effective in the prevention and treatment of breast cancer, but its use is associated with an increased risk of thrombosis. The mechanism for this effect is unknown. Reactive oxygen intermediates enhance platelet-dependent thrombosis, and in oncological studies, tamoxifen has been shown to increase production of reactive oxygen species. Therefore, the effects of tamoxifen and its b...

The beneficial effect of the selective estrogen receptor (ER) modulator tamoxifen in the treatment and prevention of breast cancer is assumed to be through its ability to antagonize the stimulatory actions of estrogen, although tamoxifen can also have some estrogen-like agonist effects. Here, we report that, in addition to these mixed agonist/antagonist actions, tamoxifen can also selectively r...

Tamoxifen has been the mainstay of endocrine therapy for estrogen receptor-positive breast cancer. However, approximately 40% of breast cancer patients do not respond to tamoxifen treatment. Further, most tumors eventually acquire tamoxifen resistance. Therefore, it is necessary to develop effective modalities to enhance the efficacy of tamoxifen in breast cancer treatment. In this study, we in...