Selenium's Dual Role in Prostate Cancer: Stimulating Growth and Inducing Apoptosis

Scientists have discovered new findings in prostate cancer research, revealing that selenium can have a dual effect on cancer cells. According to a study published in Nutrition and Cancer, low concentrations of selenium can stimulate the growth of hormone-sensitive prostate cancer cells, while higher concentrations can induce apoptosis, or cell death, in advanced prostate cancer cells. This research highlights the complex relationship between selenium and prostate cancer, and emphasizes the need for further investigation into its potential benefits and drawbacks.

Key Takeaways:

• The study, conducted by N.O. Kandas and colleagues at the University of Illinois, examined the effects of selenium on prostate cancer cells and found that low concentrations can stimulate the growth of hormone-sensitive cells.
• The study found that androgen-sensitive LNCaP cells were more sensitive to growth stimulation by low selenium concentrations than androgen-independent PC-3 cells.
• However, higher concentrations of selenium induced apoptosis in both LNCaP and PC-3 cells.
• The researchers concluded that noncytotoxic selenite concentrations did not induce growth inhibition or apoptosis selectively in prostate cancer cells, and that the potential benefits and drawbacks of selenium supplementation in prostate cancer treatment need further investigation.
• The study further revealed that PC-3 cells were refractory to apoptosis induction but were growth inhibited at noncytotoxic concentrations, while LNCaP cells were growth stimulated at 1 micromol/l and sensitive to apoptosis induction at higher noncytotoxic concentrations.
• The study used various methods to assess cell proliferation, viability, and apoptosis, including MTT assay, trypan blue exclusion, flow cytometry, DNA laddering, and caspase activation.
• The study's findings suggest that selenium may have a dual role in prostate cancer, with potential benefits for advanced cancer but potential risks for hormone-sensitive cancer.

Statistics:

• 1-to-10 micromol/l selenium concentrations were tested on prostate cancer cells for 24-to-72 hours.
• BPH-1 cells were more sensitive to cytotoxic selenium effects than malignant prostate cells.
• LNCaP cells were growth stimulated at 1 micromol/l and sensitive to apoptosis induction at higher noncytotoxic concentrations.
• PC-3 cells were refractory to apoptosis induction but were growth inhibited at noncytotoxic concentrations.
• Selenium concentrations of 1 micromol/l resulted in 50% growth inhibition of LNCaP cells.

Sources:

• Kandas, N.O. et al. (2009). Differential effects of selenium on benign and malignant prostate epithelial cells: stimulation of LNCaP cell growth by noncytotoxic, low selenite concentrations. Nutrition and Cancer, 61(2), 251-64.
• University of Illinois, Department of Pathology
• Taylor & Francis Group Ltd, 2 Park Square, Milton Park, Abingdon, Oxford OX14 4RN United Kingdom.