Gentamycin

The cancer cell line MCF-7 (human breast adenocarcinoma) was purchased from the American Type Culture Collection (ATCC, Manassas, VA, USA). The cancer cell lines NKE (human renal tubule epithelium) and MDA-MB-231 (human breast adenocarcinoma) were purchased from the cell bank of N. N. Blokhin National Medical Research Center of Oncology of the Russian Ministry of Health. MDA-MB-231, NKE, and MCF-7 cells were cultivated in DMEM substratum together with the addition of gentamycin (50 μg/mL) and 10% fetal bovine serum. Cells were cultivated in plastic cell culture flasks (25 cm²) at 37 °C in a humidified environment with 5% CO₂. Cells were seeded before reaching 80% fusion using EDTA/trypsin solution.
For the in vitro experiments, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrasolium bromide (MTT) and Mowiol (Sigma–Aldrich); 96% ethanol (Chimmed, Moscow, Russia); fetal bovine serum (FBS) (Gibco, Waltham, MA, USA); Dulbecco’s modified Eagle’s medium (DMEM) (Gibco); dimethyl sulfoxide (DMSO) (Amreso, Solon, OH, USA); 0.02% EDTA and 0.05% trypsin solutions (Gibco); and gentamycin (PanEco, Moscow, Russia) were used. All chemicals were used without further purification. Milli-Q water was used in the experiments.

Polyamidoamine dendrimer (PAMAM 4th generation) was purchased from Dentritech (Midland, MI, USA). NHS-PEG-Mal (MW 5 kDa), and NHS-PEG-OCH₃ (MW 5 kDa) purchased from RuixiBiotech (Xian, China). Solid-phase methods were applied to synthesize IELQARCRR and KQEFLINCRR peptides. D₂O, arsenazo III, GdCl₃, reduced glutathione (GSH), 4,4′-Dithiodipyridine (DTDP), and 3-(4,5-Dimethylthiazol-2yl)-2,5,diphenyltetrazolium bromide (MTT reagent) were purchased from Sigma-Aldrich (St. Louis, MO, USA). p-SCN-Bn-DTPA was purchased from Macrocyclics (Plano, TX, USA). DMEM and FBS were purchased from Gibco (Waltham, MA, USA). Hoechst 33342, Fluorescein isothiocyanate (FITC), and Cy5.5 N-hydroxysuccinimide (Cy5.5-NHS) were purchased from Lumiprobe (Moscow, Russia). Penicillin–streptomycin and gentamycin were purchased from PanEco (Moscow, Russia). NaHCO₃, NH₄CH₃CO₂, and PBS were purchased from Chimmed (Moscow, Russia). 10 kDa MWCO dialysis bags were purchased from CelluSep (Seguin, TX, USA).

In this study, we used the Caki-1 cell line, a popular model of metastatic kidney carcinoma [24 (link)]. Caki-1 cells were kindly provided by Dr. Maria Kost-Alimova (Karolinska Institute, Stockholm, Sweden). Cells were cultured in DMEM medium (PanEco, Moscow, Russia) with the addition of 10% fetal bovine serum (FBS; HyClone, Logan, UT, USA), 2 mM L-glutamine (PanEco, Moscow, Russia), and 40 μg/mL gentamycin (PanEco, Moscow, Russia) in the atmosphere containing 5% CO₂ at 37 °C.

Phosphate buffered saline (PBS) (Biolot, St. Petersburg, Russia); 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrasolium bromide (MTT) and Mowiol (Sigma-Aldrich, St. Louis, MO, USA); 96% ethanol (Chimmed, Moscow, Russia); Dulbecco’s modified Eagle’s medium (DMEM) (Gibco, Waltham, MA, USA); fetal bovine serum (FBS) (Gibco, Waltham, MA, USA); 0.9% saline (PanEco, Moscow, Russia); dimethyl sulfoxide (DMSO) (Amreso, Solon, OH, USA); 0.02% EDTA; 0.05% trypsin solutions (Gibco, Waltham, MA, USA); and gentamycin (PanEco, Moscow, Russia) were used for the experiments with cell cultures. BCA protein assay kit, lysozyme (Thermo Fisher, Waltham, MA, USA), BSA, and bovine fibrinogen (type I-S) (Sigma-Aldrich, Burlington, MA, USA). Blood collection tubes (Vacuette, Greiner Bio-One, Kremsmünster, Austria).

The fibrous mats cytocompatibility was analyzed using NIH 3T3 cells (mouse embryonic fibroblasts cell line). The culture medium consisted of Dulbecco’s Modified Eagle’s Medium (DMEM)/F12 supplemented with L-glutamine (1:1, Biolot, St. Petersburg, Russia), 10% fetal calf serum (HyClone, Logan, UT, USA), and gentamycin (50 μg/mL, Paneco, Moscow, Russia). Cell morphology was routinely checked with a phase-contrast microscope Primovert (Carl Zeiss, München, Germany).

Human MSCs were collected from biopsies of the gingival mucosa from the retromolar area of the healthy donors who had signed the informed consent. The cells were isolated and characterized according to the protocol described in Ref. 50 (link). Cells were cultured in DMEM/F12 medium (1:1, Biolot, Russia) supplemented with 10% fetal calf serum (HyClone), l-glutamine ( $5\mathrm{mg}/\mathrm{mL}$ , Gibco), insulin-transferrin-sodium selenite (1:100, Biolot), bFGF ( $20\mathrm{ng}/\mathrm{mL}$ , ProSpec, Israel), and gentamycin ( $50\mu \mathrm{g}/\mathrm{mL}$ , Paneco, Russia). We used MSCs of the fourth passage in this study. The cell morphology was examined using a phase-contrast microscope Primovert (Carl Zeiss).