Prevention of prostate cancer with vitamins - current perspectives

Suppression of LASP-1 attenuates the carcinogenesis of prostatic cancer cell lines: Key role of the NF-κB pathway

Prostate cancer (PCa) is one of the most frequently diagnosed cancers among males worldwide and causes a considerable number of deaths each year. One of the newly explored targets for the development of therapies against PCa is LIM and SH3 protein 1 (LASP-1). In the present study, the function of LASP-1 in the oncogenesis and metastasis of PCa was investigated using a series of in vitro experiments. Moreover, the mechanism through which LASP-1 exerted its effect on the carcinogenesis of PCa was also explored. The expression levels of LASP-1 in clinical PCa specimens were determined both at the mRNA and protein levels. Afterwards, the activity of LASP-1 in human PCa cell lines PC3 and DU145 was inhibited using a short hairpin RNA (shRNA) interfering method. The effects of LASP-1 knockdown on the cell growth, apoptosis, cell cycle distribution, migration and invasion were assessed. It was demonstrated that the expression of LASP-1 was significantly higher in the clinical PCa tissues than the level in the corresponding para-carcinoma tissues. Following the knockdown of the LASP-1 gene in human PCa cell lines, the viability, migration and invasion of the cancer cells were decreased. It was also demonstrated that the change in the cell viability and motile ability were associated with an induction of cell apoptosis and G1 phase cell cycle arrest. Based on the results of the detection of the expression of NF-κB-related factors, it was indicated that LASP-1 may affect the carcinogenesis of PCa through a NF-κB inhibition-dependent manner. Although the detailed explanation of the mechanism of LASP-1 in the carcinogenesis of PCa requires further elucidation, the present study highlights the potential of LASP-1 as a promising therapeutic target to ameliorate the oncogenesis and metastasis of PCa.

Conditional PTEN-deficient mice as a prostate cancer chemoprevention model

BACKGROUND

We generated a mouse model of prostate cancer based on the adult-prostate-specific inactivation of phosphatase and tensin homolog (PTEN) using the Cre-loxP system. The potential of our mice as a useful animal model was examined by evaluating the chemopreventive efficacy of the anti-androgen, chlormadinone acetate (CMA).

MATERIALS AND METHODS

Six-week-old mice were treated subcutaneously with 50 μg/g of CMA three times a week for 9 or 14 weeks and sacrificed at weeks 15 and 20. Macroscopic change of the entire genitourinary tract (GUT) and histologically evident prostate gland tumor development were evaluated. Proliferation and apoptosis status in the prostate were examined by immunohistochemistry.

RESULTS

CMA triggered significant shrinkage of not only the GUT but also prostate glands at 15 weeks compared to the control (p=0.017 and p=0.010, respectively), and the trend became more marked after a further five-weeks of treatment. The onset of prostate adenocarcinoma was not prevented but the proliferation of cancer cells was inhibited by CMA, which suggested the androgen axis is critical for cancer growth in these mice.

CONCLUSIONS

Conditional PTEN-deficient mice are useful as a preclinical model for chemoprevention studies and serve as a valuable tool for the future screening of potential chemopreventive agents.

Biomarkers for evaluation of prostate cancer prognosis

Prostate cancer, with a lifetime prevalence of one in six men, is the second cause of malignancy-related death and the most prevalent cancer in men in many countries. Nowadays, prostate cancer diagnosis is often based on the use of biomarkers, especially prostate-specific antigen (PSA) which can result in enhanced detection at earlier stage and decreasing in the number of metastatic patients. However, because of the low specificity of PSA, unnecessary biopsies and mistaken diagnoses frequently occur. Prostate cancer has various features so prognosis following diagnosis is greatly variable. There is a requirement for new prognostic biomarkers, particularly to differentiate between inactive and aggressive forms of disease, to improve clinical management of prostate cancer. Research continues into finding additional markers that may allow this goal to be attained. We here selected a group of candidate biomarkers including PSA, PSA velocity, percentage free PSA, TGFβ1, AMACR, chromogranin A, IL-6, IGFBPs, PSCA, biomarkers related to cell cycle regulation, apoptosis, PTEN, androgen receptor, cellular adhesion and angiogenesis, and also prognostic biomarkers with Genomic tests for discussion. This provides an outline of biomarkers that are presently of prognostic interest in prostate cancer investigation.

Fruit and vegetable intake in relation to prostate cancer in Iranian men: a case-control study

BACKGROUND

Findings of epidemiologic studies on the relationship between fruit and vegetable consumption and prostate cancer (PCa) risk have been inconclusive. We therefore examined the association between intake of fruits and vegetables and PCa risk in Iran.

MATERIALS AND METHODS

In this hospital based, case-control study, a total of 50 patients with PCa and 100 controls underwent face-to-face interviews. Regression analysis was used to examine the relation between fruit and vegetable intake and PCa risk.

RESULTS

A protective independent effect was observed for the highest tertile of total fruit and vegetable (OR: 0.33, CI: 0.04-0.30, p value<0.001), total fruit (OR: 0.30, CI: 0.06-0.4, p value=0.03) and total vegetable (OR: 0.31, CI: 0.02-0.21, p value<0.001) consumption. Within the group of fruits, a significant inverse association was observed for apple and pomegranate (p trends were 0.01 and 0.016, respectively). In the vegetable group, a significant inverse association was observed for tomatoes (p trend<0.001) and cabbage (p trend=0.021).

CONCLUSIONS

The results of the present study suggested that fruits and vegetable intake might be negatively associated with PCa risk.

Epidemiology, etiology, diagnosis and treatment of prostate cancer

Prostate cancer is more common in men over the age of 65 years. There are 15% cases with positive family history of prostate cancer Worldwide. Prostate cancer is the second leading cause of death among the U.S. men. Prostate cancer incidence is strongly related to age with the highest rates in older man. Globally millions of people are suffering from this disease. This study aims to provide awareness about prostate cancer as well as an updated knowledge about the epidemiology, etiology, diagnosis and treatment of prostate cancer.