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Biodegradable Guar Gum Nanoparticles as Carrier for Tamoxifen Citrate in Treatment of Breast Cancer  [PDF]
Jayanta K. Sarmah, Saibal Kanti Bhattacharjee, Samhita Roy, Ranadeep Mahanta, Rita Mahanta
Journal of Biomaterials and Nanobiotechnology (JBNB) , 2014, DOI: 10.4236/jbnb.2014.54026
Abstract: We prepared, characterized and studied the biodistribution of tamoxifen citrate (TMX) loaded cross-linked guar gum (GG) nanoparticles (NPs). NPs were prepared via a single step emulsion process and particle size evaluated. The extent of tissue distribution and retention following oral administration of TMX loaded GG NPs and TMX tablet in female albino mice was analyzed over a period of 48 hours. Till 48 hours, the particles remained detectable in both mammary and ovary tissue (estrogen receptors). Uptake and retention of TMX from NPs and tablet in mammary gland and ovary tissue changed with time. Results showed that the uptake and retention of NPs was more in the mammary gland between 24 - 48 hours (11.2% at 24 h; 4.65% at 48 h). As mammary gland is the target organ in breast cancer therapy, it may be concluded that the cross-linked GG NPs are capable of releasing the drug at the target and minimize the uptake and retention in non target tissue, the ovary (7.98% at 24 h; 1.9% at 48 h). Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) with time were measured. No abnormal changes in the liver enzymes were observed. GG NPs under study can be used as a drug carrier system for treating cancer.
Comparison of Clomiphene Citrate Plus Estradiol, with Tamoxifen Citrate Effects in Induction of Ovulation and Pregnancy in Poly Cystic Ovarian Syndrome Patients  [PDF]
N. Moslemizadeh,T.G. Moghadam,S. Ehteshami
Journal of Medical Sciences , 2008,
Abstract: The aim of this study was to compare the rates of ovulation and pregnancy after tamoxifen citrate, clomiphene citrate and after adding estradiol (E2) to clomiphene citrate among anovulatory women with infertility. This study was a randomized double blind clinical trial conducted from Aug. 2006 to Aug. 2007 in present Infertility Clinic of Imam Education and Research Hospital, Sari, Iran. The patients were 157 anovulatory women under 35 years of age undergoing ovulation induction. Of total, 144 cases completed the study. They were assigned randomly to receive either tamoxifen citrate or clomiphene citrate on cycle days 3-9 and/or clomiphene citrate on cycle days 3-9 plus E2 on cycle days 8 until all patients undergo HCG injection. Rates of ovulation and pregnancy for the three treatment modalities were measured. Although not statistically significant, the ovulation rates was higher in TAX group compared with clomiphene citrate group or clomiphene citrate plus E2 group (77.1 vs. 60.4 vs. 58.3% p = 0.1). The overall pregnancy rates was significantly higher in women who received tamoxifen citrate compared with those who received clomiphene citrate or clomiphene citrate plus E2 (52.1 vs. 33.3 vs. 22.9%, p = 0.01). This study demonstrated Hormonal supplementation with oral Estradiol following clomiphene citrate therapy in comparison with clomiphene citrate or tamoxifen citrate could not increase ovulation and pregnancy rate.
Inhibitory effects of Indigofera aspalathoides on 20-methylcholanthrene-induced chemical carcinogenesis in rats  [cached]
Kumar S,Karrunakaran C,Rao M. R. K.,Balasubramanian M
Journal of Carcinogenesis , 2011,
Abstract: Background: The anticancer and antioxidant effects of the aqueous extract of Indigofera aspalathoides on 20-methylcholanthrene (20-MCA) induced fibrosarcoma were investigated in male albino rats. Materials and Methods: The rats were divided into four different groups, each group consisting of six animals. Group I animals were served as normal control, Group II animals were fibrosarcoma-bearing animals after the incubation period, Group III animals were fibrosarcoma-bearing animals, treated with aqueous extract of I. aspalathoides intraperitoneally at a dose of 250 mg/kg b.w. for 30 days and Group IV animals were administered with the aqueous extract of I. aspalathoides alone, at a dose of 250 mg/kg b.w. for 30 days, served as drug control animals. After the experimental period, all the rats were weighed and killed by cervical decapitation. The serum was separated from the blood for analysis. The weights of the liver and the kidneys were noted. The fibrosarcoma was proved by pathological examinations. The liver and kidney tissues were excised and then homogenized in an ice-cold buffer. These tissues were used for biochemical analysis. Results: The activities of antioxidant enzymes, e.g. catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD), in blood serum, liver, and kidney of control and experimental animals, respectively, have been reported. Conclusion: The present observations suggested that the aqueous extract of I. aspalathoides treatment enhanced the recovery from 20-MCA-induced fibrosarcoma due to its antioxidants and antineoplastic properties.
Preparation and in vitro characterization of poly (epsilon-caprolactone)-based tamoxifen citrate-loaded cylindrical subdermal implant for breast cancer  [cached]
Hiremath Jagadeesh,Devi V
Asian Journal of Pharmaceutics , 2011,
Abstract: In the present study cylindrical poly(epsilon-caprolactone) (PCL)-based biodegradable polymeric tamoxifen citrate-loaded subdermal implants were prepared by laboratory-based modified melt extrusion technique. The prepared implants were evaluated for their physicochemical parameters. Drug content in implants by high-performance liquid chromatographic (HPLC) method, differential scanning calorimetry (DSC), X-ray diffraction (XRD) and scanning electron microscope (SEM) studies of tamoxifen citrate-loaded implants. Determination of in vitro hydrolytic degradation of polymeric and tamoxifen citrate-loaded implants and in vitro drug release was carried out by using indigenously developed dissolution apparatus. DSC and XRD studies proved that the drug is entrapped in the implant. The highest rate of hydrolytic degradation (weight loss) was observed in blank implants when compared to tamoxifen citrate-loaded implants. The studies proved that the developed method have potential in terms of industrial feasibility.
Development of biodegradable polymer based tamoxifen citrate loaded nanoparticles and effect of some manufacturing process parameters on them: a physicochemical and in-vitro evaluation
Basudev Sahana, Kousik Santra, Sumit Basu, et al
International Journal of Nanomedicine , 2010, DOI: http://dx.doi.org/10.2147/IJN.S9962
Abstract: pment of biodegradable polymer based tamoxifen citrate loaded nanoparticles and effect of some manufacturing process parameters on them: a physicochemical and in-vitro evaluation Original Research (6244) Total Article Views Authors: Basudev Sahana, Kousik Santra, Sumit Basu, et al Published Date August 2010 Volume 2010:5 Pages 621 - 630 DOI: http://dx.doi.org/10.2147/IJN.S9962 Basudev Sahana, Kousik Santra, Sumit Basu, Biswajit Mukherjee Department of Pharmaceutical Technology, Jadavpur University, Kolkata, India Abstract: The aim of the present study was to develop nanoparticles of tamoxifen citrate, a non-steroidal antiestrogenic drug used for the treatment of breast cancer. Biodegradable poly (D, L- lactide-co-glycolide)-85:15 (PLGA) was used to develop nanoparticles of tamoxifen citrate by multiple emulsification (w/o/w) and solvent evaporation technique. Drug-polymer ratio, polyvinyl alcohol concentrations, and homogenizing speeds were varied at different stages of preparation to optimize the desired size and release profile of drug. The characterization of particle morphology and shape was performed by field emission scanning electron microscope (FE-SEM) and particle size distribution patterns were studied by direct light scattering method using zeta sizer. In vitro drug release study showed that release profile of tamoxifen from biodegradable nanoparticles varied due to the change in speed of centrifugation for separation. Drug loading efficiency varied from 18.60% to 71.98%. The FE-SEM study showed that biodegradable nanoparticles were smooth and spherical in shape. The stability studies of tamoxifen citrate in the experimental nanoparticles showed the structural integrity of tamoxifen citrate in PLGA nanoparticles up to 60°C in the tested temperatures. Nanoparticles containing tamoxifen citrate could be useful for the controlled delivery of the drug for a prolonged period.
Development of biodegradable polymer based tamoxifen citrate loaded nanoparticles and effect of some manufacturing process parameters on them: a physicochemical and in-vitro evaluation  [cached]
Basudev Sahana,Kousik Santra,Sumit Basu,et al
International Journal of Nanomedicine , 2010,
Abstract: Basudev Sahana, Kousik Santra, Sumit Basu, Biswajit MukherjeeDepartment of Pharmaceutical Technology, Jadavpur University, Kolkata, IndiaAbstract: The aim of the present study was to develop nanoparticles of tamoxifen citrate, a non-steroidal antiestrogenic drug used for the treatment of breast cancer. Biodegradable poly (D, L- lactide-co-glycolide)-85:15 (PLGA) was used to develop nanoparticles of tamoxifen citrate by multiple emulsification (w/o/w) and solvent evaporation technique. Drug-polymer ratio, polyvinyl alcohol concentrations, and homogenizing speeds were varied at different stages of preparation to optimize the desired size and release profile of drug. The characterization of particle morphology and shape was performed by field emission scanning electron microscope (FE-SEM) and particle size distribution patterns were studied by direct light scattering method using zeta sizer. In vitro drug release study showed that release profile of tamoxifen from biodegradable nanoparticles varied due to the change in speed of centrifugation for separation. Drug loading efficiency varied from 18.60% to 71.98%. The FE-SEM study showed that biodegradable nanoparticles were smooth and spherical in shape. The stability studies of tamoxifen citrate in the experimental nanoparticles showed the structural integrity of tamoxifen citrate in PLGA nanoparticles up to 60°C in the tested temperatures. Nanoparticles containing tamoxifen citrate could be useful for the controlled delivery of the drug for a prolonged period.Keywords: biodegradable, nanoparticles, PLGA, stability, tamoxifen citrate
Preparation and in vitro characterization of the transdermal drug delivery system containing tamoxifen citrate for breast cancer  [cached]
Adhyapak Anjana,Desai B
Asian Journal of Pharmaceutics , 2011,
Abstract: A matrix-type transdermal drug delivery system of tamoxifen citrate was developed by using a different ratio of eudragit-RL100, hydroxypropyl methyl cellulose (HPMC-K15), and ethyl cellulose (EC), by the solvent evaporation technique. The effect of the binary mixture of polymers with a penetration enhancer on the physical chemical parameters including, thickness, folding endurance, uniformity of drug content, moisture content, moisture uptake, tensile strength, and in vitro drug permeation were evaluated. The in vitro drug permeation studies were conducted by using modified Keshary-Chein diffusion cells through female Sprague Dawley rat skin using pH 7.4 phosphate buffer saline (PBS). The selected formulation′s stability studies were conducted as per the International Conference on Harmonization (ICH) guidelines, and did not show any degradation of the drug.
IN-VITRO CYTOTOXICITY ANALYSIS OF TAMOXIFEN CITRATE LOADED CROSS-LINKED GUAR GUM NANOPARTICLES ON JURKAT (HUMAN T-CELL LEUKEMIA) CELL LINE
* Jayanta K Sarmah,Rita Mahanta,Saibal Kanti Bhattacharjee,Ranadeep Mahanta
Journal of Drug Delivery and Therapeutics , 2012,
Abstract: The present investigation was aimed to study the antiproliferative action of Tamoxifen citrate (TMX), a non steroidal antiestrogen, on a human T-cell leukemia cell line, Jurkat, as free drug and TMX loaded guar gum nanoparticles. For this we developed a new formulation containing chemically cross-linked guar gum nanoparticles (GG NPs) loaded with Tamoxifen citrate (TMX). Single step (oil in water) emulsion and in-situ polymer crosslinking technique was employed to prepare spherical and smooth surfaced nanoparticles in the size range of 200-300nm. Nanoparticle size and shape was confirmed from observation in transmission electron microscope (TEM) analysis. Cytotoxicity on Jurkat (human T-cell leukemia) cell lines as determined by cell growth inhibition after 48 hrs of incubation indicated that Tamoxifen citrate loaded guar gum nanoparticles were as efficient as the free drug when applied to the cancer cells. However, the crosslinked guar gum nanoparticles loaded with Tamoxifen citrate exhibited sustained release of the drug and delayed apoptosis over a long period of time making it suitable for cancer treatment.
Tamoxifen may prevent both ER+ and ER- breast cancers and select for ER- carcinogenesis: an alternative hypothesis
Laura J Esserman, Elissa M Ozanne, Mitch Dowsett, Joyce M Slingerland
Breast Cancer Research , 2005, DOI: 10.1186/bcr1342
Abstract: BCPT and MORE data were used to investigate whether: first, tamoxifen could reduce equally the emergence of ER- and ER+ tumors; and second, tamoxifen could select a fraction of emerging ER+ cancers and promote their transformation to ER- cancers. Assuming that some proportion, Z, of ER+ tumors becomes ER- after tamoxifen exposure and that the risk reduction for both ER- and ER+ tumors is equal, we solved for both the transformation rate and the risk reduction rate.If tamoxifen equally reduces the incidence of ER+ and ER- tumors by 60%, the BCPT results are achieved with a transformation of approximately Z = 20% of ER+ to ER- tumors. Validation with MORE data using an equal risk reduction of 60% associated with tamoxifen produces an almost identical transformation rate Z of 23%.Data support an alternative hypothesis that tamoxifen may promote ER- carcinogenesis from a precursor lesion that would otherwise have developed as ER+ without tamoxifen selection.The prevailing wisdom is that tamoxifen and other antiestrogens are active in preventing the development or progression of estrogen receptor positive (ER+) breast cancers only. Efficacy of tamoxifen for ER+ breast cancer has been clearly demonstrated in both metastatic and adjuvant settings. The benefit from adjuvant tamoxifen therapy was restricted to ER+ breast cancers in the Early Breast Cancer Trialists' meta-analysis [1]. Tamoxifen does not inhibit proliferation of estrogen receptor negative (ER-) breast cancer cell lines in tissue culture or in murine xenograft models [1,2]. Recently, Allred et al. [3] tested a subset of patients from the National Surgical Adjuvant Breast and Bowel Project (NSABP) B-24 trial and demonstrated that the effectiveness of tamoxifen following lumpectomy and radiotherapy for ductal carcinoma in situ was limited to ER+ in situ cancers. Thus, it was not at all unexpected that results from the NSABP P-01 Breast Cancer Prevention Trial (BCPT), the study of tamoxifen use versus placebo, fi
Partial Inhibition of Estrogen-Induced Mammary Carcinogenesis in Rats by Tamoxifen: Balance between Oxidant Stress and Estrogen Responsiveness  [PDF]
Bhupendra Singh, Nimee K. Bhat, Hari K. Bhat
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0025125
Abstract: Epidemiological and experimental evidences strongly support the role of estrogens in breast tumor development. Both estrogen receptor (ER)-dependent and ER-independent mechanisms are implicated in estrogen-induced breast carcinogenesis. Tamoxifen, a selective estrogen receptor modulator is widely used as chemoprotectant in human breast cancer. It binds to ERs and interferes with normal binding of estrogen to ERs. In the present study, we examined the effect of long-term tamoxifen treatment in the prevention of estrogen-induced breast cancer. Female ACI rats were treated with 17β-estradiol (E2), tamoxifen or with a combination of E2 and tamoxifen for eight months. Tissue levels of oxidative stress markers 8-iso-Prostane F2α (8-isoPGF2α), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase, and oxidative DNA damage marker 8-hydroxydeoxyguanosine (8-OHdG) were quantified in the mammary tissues of all the treatment groups and compared with age-matched controls. Levels of tamoxifen metabolizing enzymes cytochrome P450s as well as estrogen responsive genes were also quantified. At necropsy, breast tumors were detected in 44% of rats co-treated with tamoxifen+E2. No tumors were detected in the sham or tamoxifen only treatment groups whereas in the E2 only treatment group, the tumor incidence was 82%. Co-treatment with tamoxifen decreased GPx and catalase levels; did not completely inhibit E2-mediated oxidative DNA damage and estrogen-responsive genes monoamine oxygenase B1 (MaoB1) and cell death inducing DFF45 like effector C (Cidec) but differentially affected the levels of tamoxifen metabolizing enzymes. In summary, our studies suggest that although tamoxifen treatment inhibits estrogen-induced breast tumor development and increases the latency of tumor development, it does not completely abrogate breast tumor development in a rat model of estrogen-induced breast cancer. The inability of tamoxifen to completely inhibit E2-induced breast carcinogenesis may be because of increased estrogen-mediated oxidant burden.
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