Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0376358 (
prostate cancer
)
59,338
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Frequent consumption of soy and soy-based products is associated with reduced cancer incidence particularly for breast, colon, and
prostate cancer
. In this study, we examined the effect of crude soy saponin extract on PMA (phorbol 12-myristate 13-acetate)-induced inflammatory responses. Human adenocarcinoma cells (HT-29) were treated with various concentrations of saponin extract for 72 h. Cell growth was measured at 24, 48 and 72 h of incubation, and the PMA-induced expressions of
cyclooxygenase-2
(
COX-2
), protein kinase C (PKC), and IkappaBalpha were determined. The results indicate that crude saponin extract decreased cell growth in a dose- and time-dependent manner. Crude soy saponin extract suppressed the degradation of IkappaBalpha in PMA-stimulated cells, while
COX-2
and PKC expressions were significantly down-regulated. These findings support the hypothesis that the soy saponins reduce the risk of colon tumorigenesis possibly by suppressing inflammatory responses.
...
PMID:Antiproliferative crude soy saponin extract modulates the expression of IkappaBalpha, protein kinase C, and cyclooxygenase-2 in human colon cancer cells. 1517 14
Constitutive overexpression of
cyclooxygenase-2
(
COX-2
) occurs frequently in several different malignancies, including lung, colon, breast, and
prostate cancer
. Clinical studies have established elevated serum insulin-like growth factor (IGF-I) content and IGF-I:IGF-binding protein 3 (IGFBP-3) ratio as risk factors for these same malignancies. Therefore, we sought to determine the link between
COX-2
expression and the IGF axis in
COX-2
gene-modified human non-small-cell lung cancer (NSCLC) cells. Overexpression of
COX-2
in NSCLC cells enhanced the antiapoptotic and mitogenic effects of IGF-I and IGF-II, facilitated the autophosphorylation of the type 1 IGF receptor, increased class IA phosphatidylinositol 3'-kinase activity, and decreased expression of IGFBP-3. Thus, these findings show that
COX-2
augments the stimulatory arm of the IGF axis.
...
PMID:Cyclooxygenase-2 modulates the insulin-like growth factor axis in non-small-cell lung cancer. 1537 67
Chronic lymphocytic leukemia (CLL) is an incurable adult leukemia characterized by disrupted apoptosis. OSU03012 is a bioavailable third-generation celecoxib derivative devoid of
cyclooxygenase-2
inhibitory activity that potently induces apoptosis in
prostate cancer
cell lines and is being developed as an anticancer therapy in the National Cancer Institute (NCI) Rapid Access to Intervention Development (RAID) program. We assessed the ability of OSU03012 to induce apoptosis in primary CLL cells and the mechanism by which this occurs. The LC50 (lethal concentration 50%) of OSU03012 at 24 hours was 7.1 microM, and this decreased to 5.5 microM at 72 hours. Additionally, we have demonstrated that OSU03012 mediates apoptosis by activation of the intrinsic, mitochondrial pathway of apoptosis but also activates alternative cell death pathways that are caspase independent. The early activation of both caspase-dependent and -independent pathways of apoptosis is novel to OSU03012 and suggests it has great potential promise for the treatment of CLL. Moreover, unlike the great majority of therapeutic agents used to treat leukemia or other forms of cancer, OSU03012 induces cell death entirely independent of bcl-2 expression. Overall, these data provide justification for further preclinical development of OSU03012 as a potential therapeutic agent for CLL.
...
PMID:A novel celecoxib derivative, OSU03012, induces cytotoxicity in primary CLL cells and transformed B-cell lymphoma cell line via a caspase- and Bcl-2-independent mechanism. 1545 89
The aberrant behavior of cancer reflects upregulation of certain oncogenic signaling pathways that promote proliferation, inhibit apoptosis, and enable the cancer to spread and evoke angiogenesis. Theoretically, it should be feasible to decrease the activity of these pathways-or increase the activity of pathways that oppose them-with noncytotoxic agents. Since multiple pathways are dysfunctional in most cancers, and cancers accumulate new oncogenic mutations as they progress, the greatest and most durable therapeutic benefit will likely be achieved with combination regimens that address several targets. Thus, a multifocal signal modulation therapy (MSMT) of cancer is proposed. This concept has already been documented by researchers who have shown that certain combinations of signal modulators-of limited utility when administered individually-can achieve dramatic suppression of tumor growth in rodent xenograft models. The present essay attempts to guide development of MSMTs for
prostate cancer
. Androgen ablation is a signal-modulating measure already in standard use in the management of delocalized
prostate cancer
. The additional molecular targets considered here include the type 1 insulin-like growth factor receptor, the epidermal growth factor receptor, mammalian target of rapamycin, NF-kappaB, hypoxia-inducible factor-1alpha, hsp90,
cyclooxygenase-2
, protein kinase A type I, vascular endothelial growth factor, 5-lipoxygenase, 12-lipoxygenase, angiotensin II receptor type 1, bradykinin receptor type 1, c-Src, interleukin-6, ras, MDM2, bcl-2/bclxL, vitamin D receptor, estrogen receptor-beta, and PPAR-. Various nutrients and phytochemicals suspected to have potential utility in
prostate cancer
prevention and therapy, but whose key molecular targets are still unknown, might reasonably be incorporated into MSMTs for
prostate cancer
; these include lycopene, selenium, green tea polyphenols, genistein, and silibinin. MSMTs can be developed systematically by testing various combinations of signal-modulating agents, in concentrations that can feasibly be achieved and maintained clinically, on human
prostate cancer
cell lines; combinations that appear promising can then be tested in xenograft models and, ultimately, in the clinic. Some signal modulators can increase response to cytotoxic drugs by upregulating effectors of apoptosis. When MSMTs fail to raise the spontaneous apoptosis rate sufficiently to achieve tumor stasis or regression, incorporation of appropriate cytotoxic agents into the regimen may improve the clinical outcome.
...
PMID:Targeting multiple signaling pathways as a strategy for managing prostate cancer: multifocal signal modulation therapy. 1552 6
Recent studies have found that
cyclooxygenase-2
(
COX-2
) protein expression was low and inducible with cytokines in
prostate cancer
cells (in the absence of serum) and that, in contrast,
COX-2
expression was high in normal prostate epithelial cells (EC). Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) was expressed at high levels in the
prostate cancer
cell line PC-3 but not in ECs. In contrast to previous findings by others, PPAR-gamma ligands did not induce PPAR-gamma expression in EC or PC-3. The present study examined the relationship between PPAR-gamma and
COX-2
expression patterns in EC and PC-3 in the presence and absence of serum and/or the PPAR-gamma agonist 15-deoxy-Delta12,14-prostaglandin J(2) (15d-PGJ(2)). We also evaluated the effects that the forced expression of PPAR-gamma1 and PPAR-gamma2 had on
COX-2
in ECs. We found that expression of PPAR-gamma and
COX-2
protein was inversely correlated in ECs and PC-3. Low
COX-2
expression in PC-3 was up-regulated by serum, and 15d-PGJ(2) blocked serum-induced
COX-2
expression and activity in a dose-dependent manner. 15d-PGJ(2) had no effect on
COX-2
expression in ECs or PPAR-gamma expression in either cell type. However, forced expression of PPAR-gamma1 or PPAR-gamma2 in ECs suppressed the high level of endogenous
COX-2
. This effect was not isoform specific and was augmented by 15d-PGJ(2). The present study showed that PPAR-gamma activation can be an important regulator of
COX-2
in prostate cells and may be an important target for
prostate cancer
chemoprevention.
...
PMID:Peroxisome proliferator-activated receptor-gamma suppresses cyclooxygenase-2 expression in human prostate cells. 1553 96
The arachidonic acid metabolizing enzymes
cyclooxygenase-2
(
COX-2
) and lipoxygenases (LOXs) have been found to be implicated in a variety of cancers, including
prostate cancer
. To develop new therapeutic treatments, it therefore seemed interesting to design dual
COX-2
/5-LOX inhibitors. We report here the synthesis and in vitro pharmacological properties of diarylpyrazole derivatives that have in their structure key pharmacophoric elements to obtain optimal interaction with subsites of active pockets in both enzyme systems. Using a molecular modeling approach, a set of SAR data is proposed, highlighting the importance of the sulfonyl group of one of the aryl moieties in terms of proliferation inhibition and/or apoptosis induction.
...
PMID:New COX-2/5-LOX inhibitors: apoptosis-inducing agents potentially useful in prostate cancer chemotherapy. 1556 90
Over the last decade, epidemiological, experimental and clinical studies have implicated oxidative stress in the development and progression of
prostate cancer
. Oxidative stress may be linked to the effects of androgens, anti-oxidant systems and the pre-malignant condition, high-grade prostatic intraepithelial neoplasia.
Cyclooxygenase-2
activity has been linked with prostate carcinogenesis. Evidence suggests that oxidative stress and cyclo-oxygenase-2 activity may be mechanistically linked. Agents such as anti-oxidants and cyclo-oxgenase-2 inhibitors may be of value in the chemoprevention of
prostate cancer
. The feasibility of intervention with such agents will depend on the development and validation of biomarkers for clinical trials, particularly markers of oxidative damage caused by reactive oxygen species (ROS). A greater understanding of the molecular events associated with oxidative stress will enhance the development of such biomarkers and should result in better strategies for the chemoprevention of
prostate cancer
.
...
PMID:Oxidative stress and cyclooxygenase activity in prostate carcinogenesis: targets for chemopreventive strategies. 1561 91
Evidence suggests that the angiogenic endothelium represents an important target through which celecoxib mediates in vivo antitumor effects. Nevertheless, the pharmacologic basis for celecoxib-caused growth inhibition in endothelial cells in vitro remains to be defined. Previously, we showed that celecoxib-induced apoptosis in PC-3
prostate cancer
cells was mediated in part through the inhibition of 3-phosphoinositide-dependent kinase-1/Akt signaling. Our present findings show that celecoxib inhibits the growth of human umbilical vein endothelial cells (HUVEC) with pharmacologic profiles reminiscent of those of PC-3 cells. The underlying antiproliferative mechanism, however, may differ between these two cell types considering differences in the functional status of many tumor suppressors, including PTEN, p53, and retinoblastoma, all of which play integral roles in regulating cell cycle progression and survival. From a mechanistic perspective, the genomic integrity of the HUVEC system presents a vastly different intracellular context to examine how celecoxib acts to induce growth inhibition. Here, we obtain evidence that the antiproliferative effects of celecoxib and its close,
cyclooxygenase-2
-inactive analogue 4-[5-(2,5-dimethylphenyl)-3(trifluoromethyl)-1H-pyrazol-1-yl]benzenesulfonamide (DMC) in HUVECs at pharmacologically attainable concentrations (10-20 micromol/L) are attributable to the inhibition of phosphoinositide-dependent kinase-1/Akt signaling and cyclin-dependent kinase. Especially, celecoxib- and DMC-mediated G1 arrest is associated with attenuated retinoblastoma phosphorylation through the inhibition of multiple cyclin-dependent kinases (IC50, 10-35 micromol/L). Moreover, both celecoxib and DMC reduce neovascularization in the chicken chorioallantoic membrane assay, suggesting the involvement of a
cyclooxygenase-2
-independent mechanism in the in vivo antiangiogenic effects of celecoxib.
...
PMID:Growth inhibitory effects of celecoxib in human umbilical vein endothelial cells are mediated through G1 arrest via multiple signaling mechanisms. 1563 61
Many tumors constitutively express high levels of the inducible form of proinflammatory enzyme,
cyclooxygenase-2
(
COX-2
). Increased
COX-2
expression is associated with tumor cell resistance to many cytotoxic chemotherapy drugs. Furthermore, increased resistance to cytotoxic antitumor drugs is also known to be dependent on associated stromal cells in many tumors. We investigated whether prostate tumor-associated stromal cells, marrow-derived osteoblasts, affect cytotoxicity of 2 antitumor drugs, COL-3 and docetaxel (TXTR), and whether it is dependent on
COX-2
activity. We further examined whether inhibiting the activity of
COX-2
negate the stroma-induced decrease in drug sensitivity in tumor cells.
COX-2
-specific inhibitor celecoxib (CXB) was used to inhibit
COX-2
activity and associated alteration in cell death signaling was investigated. Coculturing PC-3ML cells with osteoblasts decreased the cytotoxicity of the tested antitumor drugs and was associated with increased
COX-2
activity in PC-3ML cells. A significant decrease in drug-induced PGE(2) increase and an increase in cytotoxicity were observed when cells were treated with COL-3 or TXTR combined with CXB. Cytotoxicity of single or combination treatment increased apoptosis, which was associated with caspase-3 and -9 activation, PARP cleavage, increased BAD protein, but decreased protein levels of XIAP and BCL-(xL). Oral administration of CXB (40 mg/kg) to mice with PC-3ML tumors for 42 days increased tumor latency, decreased tumor growth and enhanced tumor control with COL-3 or TXTR. Overall, a synergistic enhancement of antitumor activity in combination treatment was observed in vitro and an additive effect in vivo. These observations suggest a potential clinical use of combined dosing of
COX-2
inhibitors and cytotoxic drugs at lower, nontoxic dose than currently used to treat advanced
prostate cancer
.
...
PMID:Cyclooxygenase-2 inhibitor celecoxib augments chemotherapeutic drug-induced apoptosis by enhancing activation of caspase-3 and -9 in prostate cancer cells. 1568 68
Epidemiological studies have provided evidence that high intake of saturated fat and/or animal fat increases the risk of
prostate cancer
, but on the other hand, diets rich in omega-3 polyunsaturated fatty acids (n-3 PUFAs), present in fish oils were found to reduce the risk. There are indications of an increased expression of immunoreactive PPARgamma in prostatic intraepithelial neoplasia (PIN) and
prostate cancer
, suggesting that PPARgamma ligands may exert their own potent anti-proliferative effect against
prostate cancer
. The experimental evidence for the role of
cyclooxygenase-2
(
COX-2
) in prostate carcinogenesis is well established through several investigations. It clearly suggests the need for development of strategies to inhibit
COX-2
mediated prostate carcinogenesis. However, administration of high doses of
COX-2
inhibitors, such as celecoxib, over longer periods may not be devoid of side effects. We assessed the efficacy of DHA and celecoxib individually and in combination at low doses in three
prostate cancer
cell lines (LNCaP, DU145 and PC-3) measuring cell growth inhibition and apoptosis, and on the levels of expression of
COX-2
, nuclear factor-kappaB (NF-kappaBp65), and nuclear receptors, such as PPARgamma and retinoid X receptors (RXR), all of which presumably participate in prostate carcinogenesis. A 48-h incubation of
prostate cancer
cells with 5 microM each of DHA or celecoxib induced cell growth inhibition and apoptosis, and altered the expression of the above molecular parameters. Interestingly, the modulation of these cellular and molecular parameters was more pronounced in cells treated with low doses of DHA and celecoxib (2.5 microM each) in combination than in cells treated with the higher doses of individual agents. In conclusion, the present study demonstrates for the first time that a combination of lower doses of the n-3 PUFA, and DHA with the selective
COX-2
inhibitor celecoxib effectively modulates the above cellular and molecular parameters that are relevant to
prostate cancer
. This raises the intriguing prospect that the use of low doses of a
COX-2
inhibitor in combination with an n-3 PUFA could be a highly promising strategy for
prostate cancer
chemoprevention while minimizing undesired side effects.
...
PMID:A combination of docosahexaenoic acid and celecoxib prevents prostate cancer cell growth in vitro and is associated with modulation of nuclear factor-kappaB, and steroid hormone receptors. 1570 37
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>