N methyl nitrosurea mnu

To further study the in vivo antitumor activity of PTK7-GEMs, we created a rat model of in-situ bladder cancer. Ether inhalation was used to anesthetize female SD rats, followed by infusion of their bladders with 0.2 ml of 10 mg mL^− 1 N-methyl-Nitrosurea (MNU; Sigma) using a 22-gauge angiocatheter once every two weeks, five times. Postcatheterization, spontaneous micturition was avoided by keeping the rats anesthetized for approximately 45 min. After the successful induction of tumors (about 16 w), rats (n = 60) were placed in six groups, each comprising ten rats. After anesthesia, the rats’ bladders were instilled with PBS, PTK7, LIB, GEM, LIB-GEMs, or PTK7-GEMs (with the equivalent GEM concentration of 5 mg kg^− 1). Spontaneous micturition was avoided by keeping the rats anesthetized for approximately 45 min. Treatments were given once each week for 5 w. The rats were subjected to human sacrifice at 2 days after the last dose. We dissected out the rats’ bladders, which were weighed, 4% paraformaldehyde-fixed for 24 h, paraffin-embedded, and subjected to histopathological examination. At the bladder midpoint, we cut transverse sections, followed by staining with H&E.

To determine the antitumor activity of SCNTs/si-circPRMT5 in vivo, an in situ model of bladder cancer was constructed. Ether inhalation was used to anesthetize female SD rats, whose bladders were then infused using 0.2 ml N-methyl-Nitrosurea (MNU) (10 mg/mL; Sigma, St. Louis, MO, USA,) employing a 22-gage angiocatheter once every 14 d for five times. For the avoidance of spontaneous micturition, the catheterized rats were kept under anesthesia for about 45 min [25 (link), 26 (link)].
After the successful induction of tumors, 40 rats were divided into 4 groups comprising 10 rats per group. The rats were anesthetized and their bladders were instilled with 500 μL of SCNTs/si-circPRMT5, si-circPRMT5 only, an equivalent dose of free SCNTs, or PBS. For the avoidance of spontaneous micturition, the catheterized rats were kept under anesthesia for about 45 min. These treatments were then delivered once weekly for 5 weeks. At 2 days after termination of therapy, the rats were sacrificed humanely, their bladders were removed, weighed, fixed for 1 d in 4% paraformaldehyde, paraffin-embedded, and examined histopathologically. Transverse sections cut from the midportion of the bladder were subjected to hematoxylin and eosin (H&E) staining.