Bernadette M. M. Zwaans, Kyle A. Wegner, Sarah N. Bartolone, Chad M. Vezina, Michael B. Chancellor, Laura E. Lamb
Numerous people who are treated for pelvic cancers with radiation therapy develop an often painful and disruptive condition called radiation cystitis (RC), which is known to be a side effect of radiation-induced damage to the bladder in some—but not all—patients. In a recent study, a research team sought to identify whether genetics might play a role in who is more susceptible to RC.
Using the SARRP to irradiate the bladders of three different strains of mice, the team studied the resulting effects on bladder health, paying particular attention to the changes most commonly associated with developing RC.
Ultimately, researchers concluded that “genetic factors confer sensitivity to radiation cystitis, establish C57BL/6 mice as a sensitive preclinical model, and identify a potential role for FSP1-negative stromal cells in radiation-induced bladder fibrosis.” This finding suggests that “genetic variation may also contribute to which patients develop RC in response to irradiation treatment, which could impact treatment approach and follow-up recommendations.”
The value of SARRP:
In this study, researchers assessed the results of pelvic radiation on the bladders of female mice within three common strains: C57BL/6, C3H, and BALB/c. The team used the SARRP to accurately deliver radiation in specific dosages to each mouse bladder, so they could then carefully identify the exact ways in which the treatment affected bladder anatomy, histology, and physiology. Researchers attribute “the strength and uniqueness” of their approach to “the use of the SARRP, which, unlike other studies, more closely mimics the radiation treatment used in a clinical setting and minimizes radiation toxicity or damage to surrounding tissues.”
Results showed that the strain of the mouse correlated to its increase in bladder collagen fiber density, such that C57BL/6 mice saw the greatest increase, while BALB/c mice saw variable increases, and CH3 mice saw no significant increase at all. Furthermore, results showed “different mouse strains have different bladder radiosensitivity, and that cell types other than fibroblasts are mouse strain also contributed to a rise in collagen I and III in C57BL/6 mice.”[:]