Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Neuroendocrine (NE)-like cells are hypothesized to contribute to the progression of prostate cancer by producing factors that enhance the growth, survival or metastatic capabilities of surrounding tumor cells. Many of the factors known to be secreted by NE-like cells, such as neurotensin (NT), parathyroid hormone-related peptide, serotonin, bombesin, etc., are agonists for G-protein-coupled receptors, but the signaling pathways activated by these agonists in prostate tumor cells are not fully defined. Identification of such pathways could provide insights into novel methods of treating late-stage disease. Using conditioned culture medium (CM) from LNCaP-derived NE-like cells (as a source of these agonists) or NT (a prototypical component of CM) to treat PC3 cells, we found that the epidermal growth factor (EGF) receptor (EGFR) was transactivated and that such activation was required for maximal PC3 cell mitogenesis, as measured by 5-bromo-2'-deoxy-uridine incorporation or cell number. NT also induced a time-dependent increase in EGFR Tyr(845) phosphorylation and phosphorylation of c-Src and signal transducer and activator of transcription 5b (Stat5b) (a downstream effector of Tyr(845)), events that were blocked by specific inhibition of c-Src (which mediates Tyr(845) phosphorylation of EGFR) or of EGFR. Introduction of mutant forms of EGFR (Tyr(845)) or Stat5b in PC3 cells, or treatment with selective, catalytic inhibitors of EGFR, c-Src and matrix metalloproteinases (MMPs) resulted in the loss of NT-induced stimulation of DNA synthesis, relative to wild-type controls. These data indicate that the mitogenic effect of NT on prostate cancer cells requires transactivation of the EGFR by MMPs and a novel downstream pathway involving c-Src, phosphorylation of EGFR Tyr(845) and activation of Stat5b.
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PMID:Neurotensin stimulates mitogenesis of prostate cancer cells through a novel c-Src/Stat5b pathway. 1686 79

Antitumour activity of docetaxel (Taxotere) in hormone-dependent (HD) and hormone-independent (HID) prostate cancer PAC120 xenograft model was previously reported, and its level was associated with HER2 protein expression. In the present study, we evaluate the antitumour effects of docetaxel combined with trastuzumab (Herceptin), an anti-HER2 antibody. Although trastuzumab alone had no effect on tumour growth, it potentiated the antitumour activity of docetaxel in HD tumours and more strongly in HID variants. Using the HID28 variant, we show that docetaxel treatment of tumour-bearing mice induces an increased HER2 mRNA expression of the tyrosine kinase receptor of 25-fold 24 h after docetaxel treatment, while HER2 protein and p-AKT decreased. This was followed by an increase of HER2 protein 3 days (two-fold) after docetaxel treatment and by a strong HER2 release in the serum of treated mice; expression of phospho-ERK, p27, BCL2 and HSP70 concomitantly increased. Similar molecular alterations were induced by docetaxel plus trastuzumab combination, except for that there was a transient and complete disappearance of AR and HSP90 proteins 24 h after treatment. We show that in addition to its known effects on tubulin and mitotic spindles, docetaxel induces complex signalisation pathway mechanisms in surviving cells, including HER2, which can be pharmacologically targeted. This study suggests that the docetaxel/trastuzumab combination may prove an effective therapeutic approach for HER2-expressing hormone-refractory prostate cancer.
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PMID:Potentiation of antitumour activity of docetaxel by combination with trastuzumab in a human prostate cancer xenograft model and underlying mechanisms. 1721 67

The antiangiogenic and antineoplastic activities of the butyric acid prodrugs AN-7 and AN-9 were demonstrated in vitro with HUVEC by inhibition of proliferation and vascular tubes formation, enhanced apoptosis, and inhibition of 22Rv-1 cells migration. In the sc implanted human prostate tumors (22Rv-1) in nude mice, AN-7 significantly inhibited Ki-67, HIF-1alpha, HER-2/neu, bFGF and increased PTEN level. AN-7 and AN-9 reduced hemoglobin accumulation in matrigel plugs implanted sc in Balb-c mice. Herein, we show that the anticancer activity of AN-7 and AN-9 can be attributed in part to their antiangiogenic activities suggesting potential therapeutic benefits for prostate cancer patients.
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PMID:The anticancer prodrugs of butyric acid AN-7 and AN-9, possess antiangiogenic properties. 1761 Oct 19

Gene therapy strategies may accelerate the development of prophylactic immunotherapy against cancer. We synthesized a lentiviral (LV) vector encoding a kinase-deficient form of erbB2 (erbB2tr) to transduce murine dendritic cells (DCs) efficiently. Murine erbB2 models a clinically relevant tumor-associated self-antigen; its human homolog (HER-2/neu) is overexpressed in breast cancer and in 80% of metastatic prostate cancers. Following one infection, approximately 47% of DCs overexpressed erbB2tr. To determine whether low doses of transduced DCs could protect mice from prostate cancer cells, we performed prime/boost vaccinations with 2 x 10(3) or 2 x 10(5) erbB2tr-transduced DCs. Six weeks after vaccination, mice were simultaneously bilaterally challenged with the aggressive RM-1 prostate cancer cell line and an erbB2tr-expressing variant (RM-1-erbB2tr). Whereas control mice developed both tumors, all recipients of 2 x 10(5) erbB2tr-transduced DCs developed only wild-type RM-1 tumors. One-third of mice vaccinated with just 2 x 10(3) erbB2tr-transduced DCs also demonstrated erbB2tr-specific tumor protection. Protection against RM-1-erbB2tr tumors was associated with sustained levels of anti-erbB2tr antibody production and also correlated with erbB2tr-specific Th1 cytokine secretion. Depletion of CD4(+), CD8(+), or natural killer (NK) cells prior to tumor challenge underscored their role in mediating tumor protection. We conclude that administration of DCs expressing a self-antigen through efficient LV-based gene transfer activates cellular and humoral immunity, protecting host animals against specific tumor challenge.
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PMID:Tumor protection following vaccination with low doses of lentivirally transduced DCs expressing the self-antigen erbB2. 1818 Jul 74

Incidental prostate cancer (PCa) has been demonstrated at autopsy in about 80% of men aged 80 years and above and also in 10%-15% of younger men aged 30-50 years in the United States. These data imply a wide variation in aggressiveness of prostate cancer, from indolent tumors to aggressive cancers that kill the patients. The use of prostate specific antigen (PSA) in screening for PCa may detect even indolent disease for which radical prostatectomy may not be necessary. Currently available criteria such as histological grade, PSA level, stage of the disease do not always predict outcome. Furthermore, only about 80% of men with metastatic PCa will respond to first line hormone manipulation and once the patient develops hormone resistant prostate cancer (HRPCa), survival remains poor. Recent genomic and proteomic studies have provided many novel molecular markers that may help to redefine prognostic parameters. This paper is a review of studies using these novel markers in order to determine whether prostate cancer patients with the following characteristics have more aggressive cancer than those without: a) high serum levels of cathepsin B, survivin, Her - 2 / neu, IGFBP-2; b) low serum stefin A, IGFBP-3, c) positive immuno-staining of primary tumors for Her-2/neu, survivin and cathepsin B / stefin A ratio > 1 and d) gene expression of AMACR, HER-2/neu, high Bcl-2: Bax ratio and EZH2 in cancer cells. These markers have been chosen for review because they are among the most promising markers emerging currently.
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PMID:The importance of determining the aggressiveness of prostate cancer using serum and tissue molecular markers. 1840 43

Synchronous or metachronous occurrences of both prostate cancer and male breast cancer are rarely reported, but provide insight into their hormonal and genetic biology. We sought to determine the incidence of prostate cancer in male breast cancer patients at our institution, and to examine estrogen receptor (ER), progesterone receptor (PR) and HER-2/neu receptor (HR) status in these patients. A retrospective review was conducted of male breast cancer patients from 1990 to 2006. Histopathologic characteristics and hormone receptor expression was obtained. In 69 patients with male breast cancer, 12 (17%) also had a diagnosis of prostate cancer. Nine had ER-positive status and three were unreported. PR status was positive in 5, whereas 3 had PR-negative status. HR status was positive in 1, whereas 5 had HR-negative status. Male breast cancer patients in this cohort have an incidence of prostate cancer higher than would be predicted in the general population; this risk factor has implications for careful prostate cancer screening.
Prostate Cancer Prostatic Dis 2009
PMID:Incidence of prostate cancer in male breast cancer patients: a risk factor for prostate cancer screening. 1850 55

Gastric cancer is the second most common cause of cancer death worldwide, and annually it causes over 150,000 deaths in Europe and 700,000 deaths globally. The incidence of gastric cancer shows an enigmatic male dominance with a male-to-female ratio of about 2:1. This sex ratio cannot be entirely attributed to the differences in the prevalence of known risk factors between the sexes. This review focuses on the potential role of oestrogen in explaining the male predominance in gastric cancer. Some data argue in favour of sex hormonal influence. Women with a longer fertility life and those on hormone replacement therapy seem to have a decreased risk of gastric cancer, and men who have been treated with oestrogen for prostate cancer have a decreased risk. Use of tamoxifen in women seems to increase their risk of gastric cancer. Animal studies indicate that oestrogen may offer protection against the development of this cancer as for example ovariectomised mice are at an increased risk, whilst administration of female sex hormones decreases the incidence of gastric cancer. Oestrogen may exert its effect by acting on oestrogen receptors (ERs). Both ERalpha, ERbeta and the latest discovered ERbetacx have been identified in gastric tissue. The biological means behind this is not yet clear but various mechanisms have been suggested. There are indications that oestrogen may lead to an increased expression of trefoil factor proteins, which protect mucous epithelia or inhibit the expression of c-erb-2 oncogene.
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PMID:Oestrogen and the enigmatic male predominance of gastric cancer. 1875 83

It is hypothesized that ligand-independent activation of the androgen receptor is one of the mechanisms implicated in tumour progression. However, supportive evidence is limited to the effect of HER-2/neu that stimulates prostate cancer progression through activation of the androgen receptor. In the present study, we have asked whether the proinflammatory cytokine interleukin-6 (IL-6), which is known to stimulate androgen receptor activity and expression of its downstream target genes, may also induce growth of androgen-sensitive cells. We have found that IL-6 differentially regulates proliferation of LAPC-4 and MDA PCa 2b cells. In MDA PCa 2b cells, growth stimulation by IL-6 was reversed by administration of either the non-steroidal anti-androgen bicalutamide or the inhibitor of the mitogen-activated protein kinase pathway PD98059. Neither cell line was found to express endogenous IL-6. Interestingly, the treatment of those prostate cancer cells did not increase phosphorylation of STAT3. The effect of IL-6 on stimulation of androgen receptor activity in MDA PCa 2b cells was lower than that of androgen, comparable with findings reported by other researchers. However, growth of MDA PCa 2b xenografts in castrated animals treated with IL-6 was similar to that in non-castrated animals. In addition, bicalutamide showed an inhibitory effect on IL-6-regulated growth in vivo. Taken together, data in the present study demonstrate that IL-6 may cause growth of androgen receptor-positive tumours in vitro and in vivo through activation of the androgen receptor.
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PMID:Interleukin-6 stimulation of growth of prostate cancer in vitro and in vivo through activation of the androgen receptor. 1901 Oct 39

Curcumin, the active component of turmeric, has been shown to protect against carcinogenesis and prevent tumor development in cancer. To enhance its potency, we tested the efficacy of synthetic curcumin analogues, known as FLLL11 and FLLL12, in cancer cells. We examined the impact of FLLL11 and FLLL12 on cell viability in eight different breast and prostate cancer cell lines. FLLL11 and FLLL12 (IC(50) values 0.3-5.7 and 0.3-3.8 micromol/L, respectively) were substantially more potent than curcumin (IC(50) values between 14.4-50 micromol/L). FLLL11 and FLLL12 were also found to inhibit AKT phosphorylation and downregulate the expression of HER2/neu. In addition, we demonstrate for the first time that FLLL11 and FLLL12 inhibit phosphorylation of signal transducer and activator of transcription (STAT) 3, an oncogene frequently found to be persistently active in many cancer types. The inhibition of STAT3 signaling was confirmed by the inhibition of STAT3 DNA binding and STAT3 transcriptional activity. Furthermore, FLLL11 and FLLL12 were more effective than curcumin in inhibiting cell migration and colony formation in soft agar as well as inducing apoptosis in cancer cells. These results indicate that FLLL11 and FLLL12 exhibit more potent activities than curcumin on the inhibition of STAT3, AKT, and HER-2/neu, as well as inhibit cancer cell growth and migration, and may thus have translational potential as chemopreventive or therapeutic agents for breast and prostate cancers.
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PMID:New curcumin analogues exhibit enhanced growth-suppressive activity and inhibit AKT and signal transducer and activator of transcription 3 phosphorylation in breast and prostate cancer cells. 1955 77

MicroRNAs (miRNAs) are short, non-coding RNAs that regulate gene expression and are aberrantly expressed in human cancer. The ERBB-2 tyrosine kinase receptor is frequently overexpressed in prostate cancer and is associated with disease progression and poor survival. We have identified two specific miR-331-3p target sites within the ERBB-2 mRNA 3'-untranslated region and show that miR-331-3p expression is decreased in prostate cancer tissue relative to normal adjacent prostate tissue. Transfection of multiple prostate cancer cell lines with miR-331-3p reduced ERBB-2 mRNA and protein expression and blocked downstream phosphatidylinositol 3-kinase/AKT signaling. Furthermore, miR-331-3p transfection blocked the androgen receptor signaling pathway in prostate cancer cells, reducing activity of an androgen-stimulated prostate-specific antigen promoter and blocking prostate-specific antigen expression. Our findings provide insight into the regulation of ERBB-2 expression in cancer and suggest that miR-331-3p has the capacity to regulate signaling pathways critical to the development and progression of prostate cancer cells.
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PMID:miR-331-3p regulates ERBB-2 expression and androgen receptor signaling in prostate cancer. 1958 56


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