Effects of local prostatic hyperthermia on human NK and T cell function

Area of Science:

• Immunology
• Oncology
• Urology

Background:

• Patients with advanced prostate cancer (CAP) exhibit significantly lower immune parameters compared to benign prostatic hyperplasia (BPH) patients and healthy volunteers.
• Pre-treatment immune studies revealed diminished CD4+/CD8+ ratios and mitogen transformation indices in CAP patients.

Purpose of the Study:

• To investigate the effects of transrectal microwave hyperthermia (TRHT) on immune responses in patients with advanced prostate cancer (CAP) and benign prostatic hyperplasia (BPH).
• To evaluate changes in lymphocyte subsets, mitogen transformation, and NK cytotoxicity following TRHT.

Main Methods:

• Thirty patients (15 CAP, 15 BPH) received six sessions of local TRHT (2450 MHz or 434 MHz) at 45°C for 30 minutes per session.
• Immune parameters were assessed before, immediately after, and at 1, 2, 4, and 6 months post-therapy.
• Comparisons were made with 30 healthy male volunteers.

Main Results:

• TRHT induced a transient, significant stimulation of cell-mediated immune parameters in CAP patients, peaking at 2 months post-treatment.
• Natural Killer (NK) cytotoxic activity significantly increased in CAP patients post-TRHT, reaching 120-130% of baseline values.
• BPH patients showed a lesser degree of immune stimulation, while healthy volunteers exhibited no substantial changes.

Conclusions:

• Local TRHT demonstrates a transient positive effect on cell-mediated immunity and NK cell activity in patients with advanced prostate cancer.
• These findings suggest potential clinical relevance for TRHT in modulating immune responses in CAP patients.
• Further studies are warranted to confirm these immunomodulatory effects of localized hyperthermia.