Tested A549 cells are placed in 96-well flat-bottom plates at a density of 5×10³ cells per well 24 h before the addition of the test compounds. The cells are incubated for 96 h with two different concentrations (10 and 100 nM) of PRI-2191 and concurrently with various concentrations of Imatinib mesylate (10, 100, 1000 and 10,000 ng/mL) and other cytostatic drugs (Docetaxel (DTX) or Idarubicin (ID) : 0.1, 1, 10, 100 ng/mL; Cisplatin (CIS): 1, 10, 100, 1000 ng/mL). The sulforhodamine B (SRB) assay is performed to evaluate the cytotoxic effect. As a result, IC₅₀ is calculated for each separate experiment in Cheburator 0.4, Dmitry Nevozhay software^[4].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

Mice^[4]
NOD/SCID female mice, 12-16 weeks old, body weight of 20-25 g, are used. Mice are subcutaneously (s.c.) inoculated in the right flank of the abdomen with A549 tumor cells suspension (5×10⁶ cells in 0.2 mL of Hank’s medium per mouse, Day 0) and then are randomized into groups receiving varied combinations of vitamin D analogs and chemotherapeutics. One out of two experimental protocols is applied in the respective experiments: 1. The treatment is started from Day 7 after inoculation of tumor cells (when tumors become palpable). Imatinib mesylate is administered intraperitoneally (i.p.) at a dose of 75 mg/kg/day, daily for 19 days (from Days 7-25). PRI-2191 is administered s.c. or by oral gavage at a dose of 2 μg/kg/day, 3 times a week (on Days 7, 12, 14, 16, 19, 21 and 23). 2. The treatment is started from Day 7 after inoculation of tumor cells (when tumors become palpable). Imatinib mesylate is administered intraperitoneally (i.p.) at a dose of 50 mg/kg/day, daily for 13 days (from Days 7-19). PRI-2191 and PRI-2205 are administered s.c. at doses of 1 or 10 μg/kg/day, respectively, 3 times a week (on Days 7, 10, 12, 14, 17, 19, 21, 24 and 26). At the end of the experiments, blood is collected under anesthesia; then, the mice are sacrificed.
Rats^[5]
Male Lewis rats weighing 270 to 320 g are used in the experiments. Imatinib mesylate (50 mg/kg) is injected intraperitoneally in the Imatinib group (n=7), and 0.5 mL of 20% DMSO without Imatinib is administered in the vehicle group (n=7). The dose of 25 mg/kg is preliminarily tested, and it produces a little improvement in lung function without statistical significance. The dose of 50 mg/kg and intraperitoneal administration are adopted based on this result and past reports. The animals undergo left thoracotomy, and the left hilum is occluded with a small metallic clamp. The occlusion is performed 20 minutes after Imatinib or vehicle administration. During clamping, the tidal volume (TV) and respiratory rate (RR) are adjusted to 8 mL/kg and 80 breaths/min, respectively. After 90 minutes of ischemia, the clamp is removed and reperfusion is maintained for 120 minutes. During reperfusion, blood flow and ventilation are restored in the bilateral lung. In the sham group (n=6), the animals are heparinized, thoracotomized, and ventilated for 210 minutes.

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

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