Archives

  • 2022-07
  • 2022-05
  • 2022-04
  • 2021-03
  • 2020-08
  • 2020-07
  • 2020-03
  • 2019-11
  • 2019-10
  • 2019-09
  • 2019-08
  • 2019-07
  • br Effect of miR PIC Nanocarrier on Bladder Tumor

    2022-05-20


    Effect of miR-143/PIC Nanocarrier on Bladder Tumor Growth in Xenografted Mouse Model
    Polyionic copolymer (PIC) was prepared by mixing miR-143s (aniomer) with poly (ethylene glycol)-b-poly (ornithine) (block catiomer) (Figure S4A)32. To evaluate the effect of Syn-miR-143s delivered by the PIC nanocarrier (Syn-miR-143s/PIC) on Thapsigargin tu-mor growth in a xenografted mouse model, we transplanted 253J-BV cells into the back of each mouse. We injected Syn-miR-143s/Lipo or PIC intravenously into a mouse 4 times every 72 h (Figure 5A). A sig-nificant suppression of tumor growth was observed in both groups at a low dose of total, 210 mg/kg. miR-143#1 seemed to be more potent in anti-tumor activity than did miR-143#12. The PIC group was more effective at tumor suppression than the lipofectamine group in the case of miR-143#12 (Figure 5A). No body weight loss was observed in any of the groups (Figure 5A).
    To confirm the level of miR-143 in each organ, including tumor, we performed RT-PCR (Figure 5B). As a result, PIC groups Thapsigargin showed the highest blood levels of miR-143 among the groups tested. The levels of miR-143#12 in the xenografted tumors were elevated, which would reflect the levels in the blood samples (Figure 5C). Especially, the miR-143#12/PIC group showed more accumulation of miR-143 in the tumors compared with the other groups. To understand whether miR-143 delivered by PIC inhibited tumor growth through RNAi, we performed an Argonaute2 (Ago2) loading assay (Figure 5D). The result suggested that miR-143 was included into the RNA-induced silencing complex (RISC) at least in part by binding with Ago2 pro-tein in the cells. Also, western blot analysis of the possible target pro-teins of miR-143 in samples from the treated tumors gave results similar to those obtained in vitro (Figures 5E and 2D). The protein levels of T-RAS and RAS-related proteins were downregulated in all treated groups compared with those in the control group. Patho-logically, lipofection caused hepatocyte toxicity, which was not observed in the case of PIC (Figure S4B).
    Effect of Intravesical Administration of miR-143#12/PIC on Orthotopic Mouse Model
    To examine the growth-inhibitory effect of miR-143#12 on the growth of bladder tumors in vivo, we used a mouse model bearing 253J-BV cell-xenografted tumors that was established by transplant-ing these cancer cells into the bladder wall of nude mice. miR-143#12/PIC, which was more effective in intravenous adminis-tration experiments, was used. The mice were treated with miR-143#12/Lipo or -143#12/PIC, and the level of miR-143 was compared in some organs (Figure S4C). Based on the results, miR-143#12 was delivered into the bladder cavity via the PIC nano-carrier, which proved to be safe and effective for general administra-tion. As a result, miR-143#12/PIC significantly inhibited the tumor growth, when compared with that for the control-miR/PIC group, and the mice treated with miR-143#12/PIC showed almost 60% in-hibition of tumor growth (Figure 6A; Figure S4D). Kaplan-Meier plots showed that the treatment group showed a significantly pro-longed animal survival when compared with the control-miR/PIC group (Figure 6B). The latter group showed remarkable weight loss compared with the former one (Figure 6C). There was an in-verse correlation between the bladder weight and body weight (data not shown).
    We also performed the Ago2 loading assay to examine whether miR-143/PIC suppressed the tumor growth through RNAi in the tu-mor cells. As shown in Figure 6D, a significant amount of miR-143
    Figure 2. Anti-proliferative Effects of Syn-miR-143s on 253J-BV Bladder Cancer Cells
    Molecular Therapy: Methods & Clinical Development