Innate immune activity in radiation Proctitis

Area of Science:

• Oncology
• Immunology
• Gastroenterology

Background:

• Radiation proctitis is a common complication of pelvic radiotherapy.
• Its exact pathophysiological mechanisms are not fully understood.
• Innate immune system activation, particularly NF-kappaB signaling, is implicated in intestinal radiation responses.

Purpose of the Study:

• To investigate innate immune responses in rectal mucosa during prostate radiotherapy.
• To examine the correlation between immune activation and acute proctitis development.

Main Methods:

• Prospective observational study of 28 prostate cancer patients undergoing radiotherapy.
• Clinical symptoms assessed using CTCAE v3.0.
• Rectal biopsies analyzed for NF-kappaB activation and cytokine gene expression (IL-1β, IL-6, IL-8, TNF-α).

Main Results:

• Significant increase in proctitis symptoms, endoscopic, and histological scores post-radiotherapy (P < 0.0001).
• NF-kappaB activation significantly increased post-radiotherapy (P < 0.0001).
• Moderate positive correlation between endoscopic scores and NF-kappaB activation (rho = 0.483, P = 0.009).

Conclusions:

• Evidence of innate immune activation in rectal mucosa during prostate radiotherapy via NF-kappaB signaling.
• Mucosal immune responses contribute to radiation proctitis.
• Potential therapeutic targets identified for mitigating gastrointestinal toxicity.