Hydroxychloroquine

Cell culture media, supplements, Hank’s balanced salt solution (HBSS), HEPES, phosphate-buffered saline (PBS), foetal calf serum (FCS), tetracycline, omeprazole, naringin, rifampicin, 4′,5′-dibromofluorescein (DBF), fumitremorgin C (FTC), the Cytotoxicity Detection Kit (LDH), and the GenElute™ Mammalian Total RNA Miniprep Kit were purchased from Sigma-Aldrich (Munich, Germany). The RevertAid™ H Minus First Strand cDNA Synthesis Kit and the Absolute QPCR SYBR Green Mix were purchased from Thermo Fisher Scientific (Waltham, MA, USA) and dimethyl sulfoxide (DMSO), Triton X-100, and crystal violet were from AppliChem (Darmstadt, Germany). Calcein acetoxymethylester (calcein-AM) was purchased from Invitrogen (Karlsruhe, Germany), pheophorbide A from Frontier Scientific Europe (Carnforth, UK), and 8-fluorescein-cAMP (8-FcA) from BIOLOG Life Science Institute (Bremen, Germany). LY335979 (zosuquidar) was obtained from Toronto Research Chemicals (Toronto, ON, Canada) and hydroxychloroquine from Cayman Chemical (Ann Arbor, MI, USA). Primers were synthesised by Eurofins MWG Operon (Ebersberg, Germany).

Compounds were purchased as follows: decitabine from Wako Pure Chemical Industries, Ltd. (Osaka, Japan); cisplatin, doxorubicin and Q-VD-OPh from Calbiochem (San Diego, CA, USA); paclitaxel from Sigma-Aldrich; and hydroxychloroquine and necrostatin-1 from Cayman Chemical (Ann Arbor, MI, USA). Stock solutions of decitabine were prepared in dimethyl sulfoxide (DMSO; Sigma-Aldrich) at concentrations of 0.5 and 1 mM.

Lectin from Triticum vulgaris was obtained from Sigma-Aldrich (St. Louis, MO, USA) and dissolved in PBS, resulting in a stock solution of 1 mg/mL. Hydroxychloroquine was acquired as a pure substance (Cayman, Ann Arbor, MI, USA) and dissolved in PBS with a stock solution of 11.5 mM. Remdesivir was obtained from Cayman Chemical (Ann Arbor, MI, USA) and dissolved in DMSO, resulting in a stock solution of 1 mM. All interventions were used at the concentrations indicated in the different experiments.
Iota-carrageenan was used as positive control in some assays and was purchased from Dupont former FMC Biopolymers (both Philadelphia, PA, USA). The dry polymer powders were dissolved in cell culture water (B Braun, Melsungen, Germany) to a final iota-carrageenan concentration of 2.4 mg/mL containing 0.5% NaCl (Merck KGA, Darmstadt, Germany). This stock solution was sterile filtered through a 0.22 mm filter (Sarstedt, Nümbrecht, Germany) and stored at 4 °C until use.