published_or_final_version / Pathology / Master / Master of Philosophy

published_or_final_version / Physiology / Master / Master of Philosophy

Prostate cancer is the most common form of non-skin cancer and the second leading cause of cancer deaths within the United States. The five year survival rate has increased from 69% to 99% over the last 25 years for the local and regional disease, but has remained fairly low (approximately 34%) for the advanced disease. Therefore, current research is aimed at finding complementary or alternative treatments that will specifically target components of the signal transduction, cell-cycle and apoptosis pathways to induce cell death, with little or no toxic side effects to the patient. In this study we investigated the effect of genistein on expression levels of genes involved in these pathways. Genistein is a (4 , 5 , 7-trihydroxyisoflavone) is a major isoflavone constituent of soy that has been shown to inhibit growth proliferation and induce apoptosis in cancer cells. The mechanism of genistein-induced cell death and potential molecular targets for genistein in LNCaP prostate cancer c ells was investigated using several techniques. The chemosensitivity of genistein towards the prostate cancer cells was investigated using the ATP and MTS assays and apoptosis induction was determined using apoptosis and caspase assays. Several molecular targets were also identified using cDNA microarray and RT-PCR analysis. Our results revealed that genistein induces cell death in a time and dose-dependent manner and regulates expression levels of several genes involved in carcinogenesis and immunogenicity. Several cell cycle genes were down-regulated, including the mitotic kinesins, cyclins and cyclin dependent kinases, indicating that genistein is able to halt cell cycle progression through the regulation of genes involved in this process. / Several members of the Bcl-2 family which are involved in apoptosis were also affected and a number of genes involved in immunogenicity were up-regulated including the DefB1 and HLA membrane receptors. The results of this study provide evidence of genistein's ability to inhibit growth proliferation and induce apoptosis and indicates its potential as an adjuvant in chemotherapy and immunotherapy. / by Kendra Merchant. / Thesis (Ph.D.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.

This study determined the impact of vitamin C dose on genistein-induced apoptosis in LNCaP cancer cells at various treatment regimens in vitro. Although the linear regression of viability assay (MTT) indicated a p-value = 0.11; NBT assay reveal a declining SOD activity during cell death. Apoptosis induction was the main mode of treatment induced cell death. The overall data showed the trend of treatment efficacy as;(Gen 10uM + Vit C 40uM) > (Gen 30uM + Vit C 40uM) > (Gen 70uM + Vit C 40uM) > 10uM genistein > 70uM genistein. The chi-square test for comparing necrosis, apoptosis and life cells showed that Vitamin C could impact genistein-induced apoptosis in LNCaP cells (p = 0.0003). This study forms the basis for in vivo studies of the impact of vitamin C on genistein-induced apoptosis in LNCaP prostate cancer cells. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection

An estimated 220,800 new prostate cancer cases and 27,540 deaths are expected to occur in US men by the end of 2015. Despite the increased treatment modes for prostate cancer, there is still no definite cure, and prognosis remains, at best, cautiously optimistic. The explicit amalgamation of two or more cancer therapeutic modalities such as surgery, radiation, and chemotherapy, has been one of the main interests of clinical investigation for several decades. Genistein (GN) and Beta-lapachone (BL) are two of the most promising anticancer phytochemical compounds. However, the anticancer activities of BL have been correlated with the enzyme activity of NQO1. The aim of this study was to investigate the enhancing effects of VLDR derived from a portable pyroelectric crystal generator on the chemopreventive and/or chemotherapeutic effects of GN and BL in NQO1+ PC3 and NQO1± (deficient) LNCaP prostate cancer cells (PCa) in vitro. The combination treat ment-induced cytotoxicity was investigated via MTT and Trypan blue exclusion assays. Dicoumarol (an NQO1 inhibitor) was co-administered to assess the effect of VLDR on NQO1 modulation. Nitro-blue tetrazolium assay was used to assess the intracellular ROS levels. Fluorescence microscopy was also used to assess the mode of cell death. In this study, a novel quantitative modeling approach was employed to comparably assess the cytotoxic effects of specific drugs used alone or in combinations with VLDR and to predict the potential synergistic therapeutic combinations. The data suggests that VLDR induced a rise in ROS levels, followed by upregulation in NQO1 levels. Pharmacodynamic indices were developed to quantify and characterize the combination treatment as synergistic, additive or antagonistic per dose or time-interval. Synergism was found to be dose and time-interval dependent. The major mode of cell death by this combination therapeutic regimen was found to be via apoptosis . In conclusion, our results confirm that VLDR enhanced cytotoxicity effects of both drugs dose- and time-dependently. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015. / FAU Electronic Theses and Dissertations Collection

Prostate cancer is one of the leading causes of death in men aged 40-55. Genistein isoflavone (4', 5', 7-trihydroxyisoflavone) is a dietary phytochemical with demonstrated anti-tumor activities in a variety of cancers. Topotecan Hydrochloride (Hycamtin) is an FDA-approved chemotherapy drug, primarily used for secondary treatment of ovarian,cervical and small cell lung cancers. This study was to demonstrate the potential anticancer activities and synergy of topotecan-genistein combination in LNCaP prostate cancer cells. The potential efficacy and mechanism of topotecan/genistein-induced cell death was investigated... Results: The overall data indicated that i) both genistein and topotecan induce cellular death in LNCaP cells, ii) topotecan-genistein combination was significantly more efficacious in reducing LNCaP cell viabiligy compared to either genistein or topotecan alone, iii) in all cases, cell death was primarily through apoptosis, via the activation of the intrinsic pathway, iv) ROS levels were increased and VEGF expression was diminished significantly with the topotecan-genistein combination treatment, v) genetic analysis of topotecan-genistein treatment groups showed changes in genetic expression levels in pathway specific apoptotic genes.... Conclusion: Treatments involving topotecan-genistein combination may prove to be an attractive alternative phytotherapy of adjuvant therapy for prostate cancer. / by Vanessa P. Hèormann. / Thesis (Ph.D.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.