A total of 5 × 105 4T1
cells, suspended in 100 μL
of PBS buffer, were subcutaneously implanted into the right flank
of female Balb/c mice. Once the tumors reached a volume of 80 mm3, the mice were randomly divided into four groups (n = 6 in each group): sham (PBS), ExomiR-CVB3, ExomiR-CVB3/Apt,
and ExomiR-CVB3/DoxApt. Mice received two intraperitoneal injections
of the above treatments on days 0 and 5, respectively. The concentration
of miR-CVB3 was 105 PFU and concentration of Dox was 3
mg/kg. Antitumor activity of each treatment was evaluated as described
earlier. At the end of the experiment, the mice were euthanized, and
tumor tissues were collected to assess apoptosis rates using the TUNEL
assay. The level of Ki67 in the tumor tissues was also evaluated using
an immunofluorescence technique with the Ki67 antibody (AB16667, ABclonal).
In a separate experiment, 4T1 tumor-bearing mice that received the
treatment as above were sacrificed on day 14 (n =
5 for each group). Tumor tissues were collected to evaluate the immune
cell infiltration in the tumor microenvironment, and different organs
were obtained for safety analysis. Moreover, the levels of TNF-α
and IFN-γ in the serum were measured using mouse TNF-α
ELISA Kit (RK00027, ABclonal) and mouse IFN-γ ELISA Kit (RK00019,
ABclonal).
cells, suspended in 100 μL
of PBS buffer, were subcutaneously implanted into the right flank
of female Balb/c mice. Once the tumors reached a volume of 80 mm3, the mice were randomly divided into four groups (n = 6 in each group): sham (PBS), ExomiR-CVB3, ExomiR-CVB3/Apt,
and ExomiR-CVB3/DoxApt. Mice received two intraperitoneal injections
of the above treatments on days 0 and 5, respectively. The concentration
of miR-CVB3 was 105 PFU and concentration of Dox was 3
mg/kg. Antitumor activity of each treatment was evaluated as described
earlier. At the end of the experiment, the mice were euthanized, and
tumor tissues were collected to assess apoptosis rates using the TUNEL
assay. The level of Ki67 in the tumor tissues was also evaluated using
an immunofluorescence technique with the Ki67 antibody (AB16667, ABclonal).
In a separate experiment, 4T1 tumor-bearing mice that received the
treatment as above were sacrificed on day 14 (n =
5 for each group). Tumor tissues were collected to evaluate the immune
cell infiltration in the tumor microenvironment, and different organs
were obtained for safety analysis. Moreover, the levels of TNF-α
and IFN-γ in the serum were measured using mouse TNF-α
ELISA Kit (RK00027, ABclonal) and mouse IFN-γ ELISA Kit (RK00019,
ABclonal).