Pe ivis spectrum

HCT116 cells stably transduced with miR-509-3p (pre-mir) or empty vector were transfected with a Firefly luciferase expressing plasmid and selected by puromycin. For the animal experiments, Luc-HCT116 cells (5,000,000) stably transduced with miR-509-3p (pre-mir) (N = 7) or empty vector (N = 4) were injected orthotopically into the cecal wall of the NOD/SCID mice. Sample size used per study arm were selected randomly to achieve a basic statistical power for evaluation. After ~ 4 weeks, the mice were euthanized by rendering them unconscious first using Sodium Pentobarbital (40–60 mg/kg IP) followed by cervical dislocation. They were subsequently dissected, and tumor development was observed by capturing the bioluminescence signal using the PE IVIS Spectrum in vivo imaging system (PerkinElmer).

Animal experiments were approved by the Ethics Committee of Weifang Medical University (2020SDL117). 5 × 10⁶ MDA-MB-231 cells were subcutaneously injected into the right hind limb of BALB/c nude female mice (age: 4 weeks; weight: 12–17 g; Vital River, Beijing, China). When tumor volume reached to 70–130 mm³, 30 mice were randomly divided into 6 groups: control (PBS), lapatinib (15 mg/kg), PAB (10 mg/kg), combination (lapatinib/PAB), vehicle (ferritin) and nanoparticle (L/P@Ferritin). Each group was treated with drugs by intraperitoneal injection every 2 days for seven times. Tumor sizes were evaluated and calculated by the following formula: 0.5 × length × width². The mice were typically euthanized by CO₂, tumors, and organs were collected for immunofluorescence and HE stain.
To generate lung metastases model, 1 × 10⁶ MDA-MB-231-luc cells were injected intravenously into NOD-SCID immunodeficient mice (female, age: 4 weeks; Vital River, Beijing, China). 12 mice were randomly divided into three groups: control (PBS), combination (lapatinib/PAB) and nanoparticle (L/P@Ferritin). Each group was treated with drugs by tail vein injection every 3 days for seven times after inoculation 14 days. Lung metastasis was evaluated using the PE IVIS Spectrum (PerkinElmer, MA, USA).

We chose 6–8 weeks old female Balb/c nude mice as animal model. The animal experiment had been approved by the Ethics Committee of Jiangyin People’s Hospital, the Jiangyin Clinical College of Xuzhou Medical University. To investigate the biodistribution of PEG-TE10-PLGA NPs in vivo, we injected 100 μL PBS containing 5 × 10⁶ TE10/DOX cells into the subcutaneous breast. When the tumor grew to nearly 300 mm³, PLGA@DiR, TE10-PLGA@DiR, and PEG-TE10-PLGA@DIR (5 mg/kg) were injected through the tail vein, and the control group was injected with equal volume of saline. After 0, 8, 24, and 48 h, tail vein blood (200 μL) was taken and the serum was collected by centrifugation. The drug concentration in blood was evaluated through the fluorescence intensity of DiR. The fluorescence intensity at the tumor site was measured with a live animal imager (Perkin Elmer PE IVIS SPECTRUM, United States). After 48 h of intravenous injection, the mice were dissected, heart, liver, spleen, lung, kidney and tumor were taken out and the fluorescence intensity in each organ and tumor tissue was measured.