Administration of antioxidant vitamins may be useful in preventing and treating prostate cancer

The findings, published online in Urologic Oncology: Seminars and Original Investigations, suggest that increased collagen turnover may occur in patients with prostate cancer. Increased prolidase seems to be related to increased oxidative stress along with decreased antioxidant levels in prostate cancer. Therefore, increased prolidase activity may, in part, play a role in the pathogenesis of prostate cancer.

Prostate cancer (PCa) remains the most frequently diagnosed neoplasm and the third leading cause of cancer-related deaths in men. Increasing evidence has suggested that oxidative stress (OS) is linked with ageing and severe age-related degenerative diseases, including cancer. Excessive production of reactive oxygen species (ROS) increases oxidative stress in the cell and leads to negative consequences such as inflammation, necrosis, and cell death.

The causes of the high incidence of prostate cancer are poorly understood, experimental, epidemiological, and clinical studies, suggest that oxidative stress plays a major role in explaining prostate cancer development and progression.

To control the balance between ROS production and removal, there are a series of protective molecules and systems known as antioxidant defences. Antioxidants which suppress such oxidative damage play critical roles in aerobic organisms. They prevent free radical-induced damage by preventing ROS formation, scavenging them, or promoting their decomposition. These include enzymes such as superoxide dismutase (SOD), Catalase (CAT), glutathione peroxidase (GPx), some vitamins, and metals.

Glutathione-S transferase (GST) is critical for detoxification. Also, glutathion (GSH) is a protector against oxidative stress. Prolidase is an expressed metallopeptidase that is uniquely needed for the breakdown of proline-rich substrates including collagen.

Against the above background, Mehmet Kaba, Department of Urology, Private Yuzyil Gebze Hospital, Kocaeli, Turkey, and colleagues aimed to identify serum prolidase activity, antioxidant enzyme levels, and oxidative stress in patients with prostate cancers and to evaluate their relationships with each other.

The study included 34 male patients with prostate cancer and with a mean age of 64.2 ± 4.4 years. The control group of 36 male patients (mean age 61.2 ± 3.4) was randomly selected among the volunteers.

Serum samples for measurements of glutathione peroxidase (GPx), superoxide dismutase, malondialdehyde (MDA), catalase, glutathione, and prolidase levels were kept at −20°C until their use.

The researchers revealed significantly higher serum prolidase activity and MDA levels in prostate cancer patients than in controls, while SOD, GPx, and CAT levels were significantly lower.

"Our results suggest that increased prolidase seems to be related to increased oxidative stress along with decreased antioxidant levels in prostate cancer," the researchers concluded.

Reference:

Kaba, M., Pirincci, N., Demir, H., & Verep, S. (2024). Serum prolidase activity, oxidative stress, and antioxidant enzyme levels in patients with prostate cancer. Urologic Oncology: Seminars and Original Investigations. https://doi.org/10.1016/j.urolonc.2024.01.007