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

The expression of thousands of genes can be monitored simultaneously using cDNA microarray technology. This technology is being used to understand the complexity of human disease. One significant technical concern regards potential alterations in gene expression because of the effect of tissue ischemia. This study evaluates the increase in the differential gene expression because of tissue processing time. To evaluate differential gene expression because of ischemia time, prostate samples were divided into five time points (0, 0.5, 1, 3, and 5 hours). Each time point consisted of a homogeneous mixture of 12 to 15 prostate tissue cubes (5 mm(3)). These tissues were maintained at room temperature until at the assigned time point the tissue was placed in OCT, flash frozen in liquid nitrogen, and stored at -80 degrees C until RNA extraction. RNA from each time point was hybridized against an aliquot of 0 time point RNA from the same prostate. Four prostate glands were used in parallel studies. M-A plots were graphed to compare variability between time point sample hybridizations. Statistical Analysis of Microarray software was used to identify genes overexpressed at the 1-hour time point versus the 0-hour time with statistically significance. Microarray analysis revealed only a small percentage of genes (<0.6%) from more than 9000 to demonstrate overexpression at the 1-hour time point. Among the 41 statistically significant named overexpressed genes at the 1-hour time point were early growth response 1 (EGR1), jun B proto-oncogene (jun B), jun D proto-oncogene (jun D), and activating transcription factor 3 (ATF3). Genes previously associated with prostate cancer did not have significantly altered expression with ischemia time. Increased EGR1 protein expression was confirmed by Western blot analysis. Microarray technology has opened the possibility of evaluating the expression of a multitude of genes simultaneously, however, the interpretation of this complex data needs to be assessed circumspectly using refined statistical methods. Because RNA expression represents the tissue response to insults such as ischemia, and is also sensitive to degradation, investigators need be mindful of confounding artifacts secondary to tissue processing. All attempts should be made to process tissue rapidly to ensure that the microarray gene profile accurately represents the state of the cells and confirmatory studies should be performed using alternative methods (eg, Northern blot analysis, Western blot, immunohistochemistry).
 ...
PMID:Changes in differential gene expression because of warm ischemia time of radical prostatectomy specimens. 1241 21

Bisphosphonates are stable analogues of pyrophosphate (PPi), an endogenous regulator of bone mineralisation. A number of placebo-controlled trials have demonstrated their positive impact on skeletal-related events (SRE) that occur as a consequence of metastatic or myelomatous bone disease. Based upon their chemical structure bisphosphonates can be classified into nitrogen-containing bisphosphonates, (N-bisphosphonates) (for example zoledronate and pamidronate) and non-nitrogen containing (for example, clodronate and etidronate), which more closely resemble PPi. Clinical trials investigating bisphosphonates in the preventative setting have shown bisphosphonates to not only delay occurrence of bone metastases in certain cancers, but in one trial, occurrence of non-osseous lesions was delayed, and survival was prolonged. Other trials however have shown the opposite. Likewise, in animal models of cancer and metastases, conflicting results have been obtained. In vitro work has concentrated on bisphosphonates direct action upon tumour cells and has found a variety of anti-tumour effects such as apoptosis induction, inhibition of cell growth, inhibition of invasive behaviour and inhibition of angiogenic factors. Furthermore it would appear that bisphosphonates have the potential to enhance anti-tumour activity of known cytotoxic drugs. Ongoing research aims to assess this further, in addition to determining more precisely the role of adjuvant bisphosphonates in cancers such as breast and prostate cancer.
 ...
PMID:The anti-tumour activity of bisphosphonates. 1247 Sep 81

Bone metastases are a common feature of a variety of solid tumors and are associated with substantial skeletal morbidity, including severe bone pain and pathologic fractures. Treatment with bisphosphonates, primarily pamidronate, is the current standard of care for patients with breast cancer and multiple myeloma who have predominantly osteolytic lesions. However, until recently no bisphosphonate had demonstrated efficacy in patients with osteoblastic lesions, which are common during the progression of prostate cancer and other solid tumors. Zoledronic acid, a potent, new-generation, nitrogen-containing bisphosphonate, has demonstrated significant benefits for patients with bone metastases resulting from a broad range of primary tumors, including multiple myeloma and breast, lung, kidney, and prostate cancers, and other solid tumors. Benefits include a decreased incidence of pathologic fractures and longer time to the first skeletal complication. Zoledronic acid is the first and only bisphosphonate to be proved effective in patients with all types of bone lesions, from osteolytic to osteoblastic, and therefore represents an important therapeutic advancement in the treatment of bone metastases.
 ...
PMID:Broad clinical activity of zoledronic acid in osteolytic to osteoblastic bone lesions in patients with a broad range of solid tumors. 1256 47

Preclinical studies are providing a growing body of evidence that bisphosphonates, particularly nitrogen-containing bisphosphonates, have antitumor activity. Bisphosphonates induce tumor cell apoptosis and reduce skeletal tumor burden in tumor xenograft models. Clinical studies with daily oral clodronate suggest that bisphosphonates can prevent bone metastases when used in the adjuvant setting, but the effect on overall survival is less certain. The more potent nitrogen-containing bisphosphonates, i.e., pamidronate and zoledronic acid, have demonstrated antitumor activity at approximately 10- to 100-fold lower concentrations than clodronate in vitro. A number of important unanswered questions must be addressed regarding the optimal use of bisphosphonates for prevention of bone metastases. For example, when should treatment begin, how long must treatment be continued, and what are the optimal dose and schedule to achieve clinically meaningful antitumor effects? Adjuvant studies of zoledronic acid in patients with breast and prostate cancer are under development, and the results are eagerly anticipated.
 ...
PMID:Future directions in the treatment and prevention of bone metastases. 1256 49

Advanced solid tumors are often aggressive and recurrent, and overall survival remains relatively poor despite contemporary therapeutic interventions. Bone metastases are common in these patients, and skeletal-related events, including bone pain, pathologic fractures, and potentially life-threatening hypercalcemia of malignancy, undermine the quality of patient survival. Bisphosphonates are widely used in the treatment of bone metastases associated with breast cancer and multiple myeloma, but have not been extensively investigated in the treatment of patients with solid tumors other than breast or prostate cancer. However, a new-generation nitrogen-containing bisphosphonate, zoledronic acid, has shown significant clinical benefits in indications in which other bisphosphonates have failed. In a phase III clinical trial in patients with bone metastases from solid tumors other than breast or prostate cancer, treatment with zoledronic acid (4 mg via 15-minute infusion) was well tolerated and significantly decreased the incidence of skeletal-related events and increased the time to first skeletal-related event compared with placebo-treated patients. This was the first demonstration of palliative efficacy for bisphosphonate therapy in patients with bone metastases from a wide variety of solid tumors.
 ...
PMID:Efficacy and safety of zoledronic acid in the treatment of bone metastases associated with lung cancer and other solid tumors. 1258 92

This work analyzes SiO2 and SiO2-CaO glasses incorporated with samarium atoms produced by sol-gel synthesis. The goal is to provide biocompatible and biodegradable radioactive seeds as an alternative to be used in brachytherapy for the treatment of prostate cancer. The chemical and physical characteristics of the obtained glasses were analyzed by energy dispersive x-ray spectroscopy, x-ray diffraction, He picnometry, and nitrogen adsorption analysis. A theoretical analysis of the process of neutron activation of the samples was also conducted through the calculation of the activity of the seeds and the beta- and gamma-ray doses emitted by the seeds. The results demonstrate the incorporation of samarium atoms in the glass matrix. The experimental data coupled with the theoretical studies in neutron activation suggest that it is possible to obtain radioactive seeds with activities equivalent to 125I seeds used in prostatic brachytherapy.
 ...
PMID:Structure and dosimetric analysis of biodegradable glasses for prostate cancer treatment. 1275 3

Zoledronic acid is a potent, third generation, nitrogen-containing bisphosphonate, licensed for the management of skeletal metastases and hypercalcaemia of malignancy, both of which cause considerable morbidity. In the preclinical setting, zoledronic acid has demonstrated superior potency regarding inhibition of osteolysis and reduction of hypercalcaemia as compared with other bisphosphonates. Clinical trials have indicated that zoledronic acid is superior to pamidronate in suppressing osteolysis and in reducing hypercalcaemia of malignancy. Its main mechanism of action is induction of osteoclast apoptosis through inhibition of the mevalonate pathway. Zoledronic acid has also demonstrated direct anti-tumour activity both in vitro and in animal models, suggesting it may be of benefit in preventing the formation of bone metastases. Clinical trials are in progress, assessing the benefit of zoledronic acid in the adjuvant setting in both breast and prostate cancer.
 ...
PMID:The use of zoledronic acid in the management of metastatic bone disease and hypercalcaemia. 1452 88

The type 1 insulin-like growth factor receptor (IGF1R) is overexpressed in prostate cancer, and mediates proliferation, motility, and survival. Many prostate cancers harbor inactivating PTEN mutations, enhancing Akt phosphorylation. This activates the principal antiapoptotic pathway downstream of the IGF1R, calling into question the value of IGF1R targeting in this tumor. The aim of the current study was to assess the effect of IGF1R gene silencing in prostate cancer cells that lack functional PTEN protein. In human DU145, LNCaP and PC3 prostate cancer cells, transfection with IGF1R small interfering RNA induced significant enhancement of apoptosis and inhibition of survival, not only in PTEN wild-type DU145 but also in PTEN mutant LNCaP and PC3. This was attributed to attenuation of IGF signaling via Akt, ERKs and p38. In both DU145 and PC3, IGF1R knockdown led to enhancement of sensitivity to mitoxantrone, etoposide, nitrogen mustard and ionizing radiation. There was no sensitization to paclitaxel or 5-fluorouracil, which do not damage DNA, suggesting that chemosensitization results from impairment of the DNA damage response, in addition to removal of apoptosis protection. These results support the concept of IGF1R targeting in prostate cancer, and indicate that PTEN loss does not render tumor cells refractory to this strategy.
 ...
PMID:Silencing of the IGF1R gene enhances sensitivity to DNA-damaging agents in both PTEN wild-type and mutant human prostate cancer. 1549 78

The effects of androgen deprivation therapy (ADT) include not only suppression of tumor growth, but also adverse effects on various bodily functions. The aim of this study was to determine the metabolic effects of ADT in patients with nonmetastatic prostate cancer. Forty-nine men with prostate cancer were treated with ADT before beginning radical therapy for 6 months. Body weight, peripheral red blood cell counts, hemoglobin, hematocrit, fasting blood sugar, serum total cholesterol, blood urea nitrogen, uric acid, compensated calcium, inorganic phosphorus, bone-specific alkaline phosphatase, urinary deoxypyridinoline, and radial bone density determined using dual energy x-ray absorptiometry were examined before and 6 months after ADT treatment. Body weight (P = 0.037) and the levels of fasting blood sugar (P = 0.014), serum total cholesterol (P = 0.017), blood urea nitrogen (P = 0.030), compensated calcium (P < 0.001), inorganic phosphorus (P < 0.001), bone-specific alkaline phosphatase (P < 0.001), and compensated urinary deoxypyridinoline (P < 0.001) increased significantly. Peripheral red blood cell counts (P < 0.001), hemoglobin level (P < 0.001), hematocrit (P < 0.001), uric acid (P < 0.001), and radial bone density (P = 0.023) decreased significantly. These effects of ADT on various bodily functions warrant systematic study in clinical trials. We should be aware of the far-reaching consequences of ADT and incorporate strategies for preventing and managing adverse effects into routine practice.
 ...
PMID:The influence of androgen deprivation therapy on metabolism in patients with prostate cancer. 1556 7

Accumulated epidemiological evidence indicates that prostate cancer mortality should be preventable. As androgenic hormones have long been recognised to be required for normal prostatic development, and because androgen deprivation is an established treatment for advanced prostate cancer, androgen signalling has been an attractive target for prostate cancer prevention. Inhibitors of 5alpha-reductase, an enzyme necessary for the conversion of testosterone to the more potent androgen dihydrotestosterone, have reached pivotal clinical trials for prostate cancer prevention. In addition, new insights into the molecular pathogenesis of prostate cancer hint that chronic or recurrent prostate inflammation may contribute to the development of the disease. A variety of antioxidants and anti-inflammatory drugs, which are likely to be capable of attenuating pro-carcinogenic genome damage from reactive oxygen and nitrogen species, are also under current development for prostate cancer prevention. This review will consider the rational development of these and other new agents and approaches for prostate cancer prevention in the context of recent research progress in ascertaining the aetiology of prostate cancer.
 ...
PMID:Agents in development for prostate cancer prevention. 1600 79


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>