ID1 enhances docetaxel cytotoxicity in prostate cancer cells through inhibition of p21.

To identify potential mechanisms underlying prostate cancer chemotherapy response and resistance, we compared the gene expression profiles in high-risk human prostate cancer specimens before and after neoadjuvant chemotherapy and radical prostatectomy. Among the molecular signatures associated with chemotherapy, transcripts encoding inhibitor of DNA binding 1 (ID1) were significantly upregulated. The patient biochemical relapse status was monitored in a long-term follow-up.

CCL2 is induced by chemotherapy and protects prostate cancer cells from docetaxel-induced cytotoxicity.

Background: Metastatic prostate cancer is either inherently resistant to chemotherapy or rapidly acquires this phenotype after chemotherapy exposure. In this study, we identified a docetaxel-induced resistance mechanism centered on CCL2.

Methods: We compared the gene expression profiles in individual human prostate cancer specimens before and after exposure to chemotherapy collected from previously untreated patients who participated in a clinical trial of preoperative chemotherapy.

The iroquois homeobox gene 5 is regulated by 1,25-dihydroxyvitamin D3 in human prostate cancer and regulates apoptosis and the cell cycle in LNCaP prostate cancer cells.

1,25-Dihydroxyvitamin D3 [1,25(OH)2D3], the most active metabolite of vitamin D3, has significant antitumor activity in a broad range of preclinical models of cancer. In this study, we show that the Iroquois homeobox gene 5 (Irx5) is down-regulated by 1,25(OH)2D3 in human prostate cancer samples from patients randomly assigned to receive weekly high-dose 1,25(OH)2D3 or placebo before radical prostatectomy. Down-regulation of Irx5 by 1,25(OH)2D3 was also shown in the human androgen-sensitive prostate cancer cell line LNCaP and in estrogen-sensitive MCF-7 breast cancer cells.

Calcitriol in the treatment of prostate cancer.

Calcitriol, the principal active metabolite of vitamin D and a naturally occurring hormone, showed significant antineoplastic activity in pre-clinical models of prostate cancer and many other tumor types. These antineoplastic effects were observed at calcitriol concentrations substantially above the physiological range. While a number of mechanisms of action have been postulated, the induction of apoptosis and inhibition of proliferation have been most extensively reported.

Neoadjuvant mitoxantrone and docetaxel for high-risk localized prostate cancer.

Purpose: Currently available treatment modalities for high-risk clinically localized prostate cancer have limited chances of achieving complete tumor elimination because of either inadequate local or metastatic tumor eradication. The goal of this phase I/II study is to evaluate the safety and efficacy of neoadjuvant docetaxel and mitoxantrone before prostatectomy.

Materials And Methods: A total of 22 men with high-risk clinically localized prostate cancer underwent weekly treatment with docetaxel (35 mg/m(2)), with increasing doses of mitoxantrone (2-5 mg/m(2)) for a 12 of 16-week treatment cycle before prostatectomy.

Effect of calcitriol on prostate-specific antigen in vitro and in humans.

Background: Calcitriol, the natural ligand for the vitamin D receptor, has significant potential in prostate cancer treatment. Measurement of its antineoplastic activity in prostate cancer clinical trials may be complicated by effects of calcitriol on prostate-specific antigen (PSA) production. We examined the effects of calcitriol at similar concentration on cell proliferation, androgen receptor (AR) expression, and PSA production in vitro and on PSA concentrations in prostate cancer patients.

Rationale for the development and current status of calcitriol in androgen-independent prostate cancer.

Calcitriol, the principal active metabolite of vitamin D, has significant antineoplastic activity in pre-clinical models of prostate cancer and many other tumor types. Reported mechanisms of activity include inhibition of proliferation and cell cycle arrest, induction of apoptosis, and reduction of invasiveness and angiogenesis. Different mechanisms may be responsible in different tumor types and under different experimental conditions.

Randomized study of high-dose pulse calcitriol or placebo prior to radical prostatectomy.

Background: Cancer chemoprevention trials require enormous resources due to the large numbers of patients and the years of follow-up needed to achieve sufficient statistical power. Examination of candidate prevention agents using biomarkers as surrogate end points has been proposed as a method to rapidly identify promising agents for prevention trials. Treatment of patients with candidate agents prior to scheduled biopsy or surgical resection of malignancy allows for direct examination of the treatment effects on tumor tissue.

Calcitriol in cancer treatment: from the lab to the clinic.

1,25-Dihydroxyvitamin D (calcitriol), the most active metabolite of vitamin D, has significant antineoplastic activity in preclinical models. Several mechanisms of activity have been proposed. These include inhibition of proliferation associated with cell cycle arrest and, in some models, differentiation, reduction in invasiveness and angiogenesis, and induction of apoptosis.