Ktc 1

Human thyroid cell line (HTori‐3), PTC cell lines (KTC‐1, K1, SNU‐790, TPC‐1), and HEK293 cells were purchased from ATCC. Cells were cultured in a standard humidified incubator with 95% air and 5% CO₂ at 37°C. Cells were cultured in DMEM (Invitrogen) supplemented with 10% Fetal bovine serum (FBS) (Gibco), and 1% streptomycin/penicillin (100 μg/mL and 100 μg/mL) (Invitrogen).

Human thyroid normal cell line, Nthy-ori 3-1, PTC cell lines (BCPAP, KTC-1, and K1), and HKE 293 cells were purchased from ATCC company (ATCC, Manassas, USA). All the cells were cultured in the Dulbecco's modified Eagles' medium (DMEM, Invitrogen, Carlsbad, USA) supplemented with 10% fetal bovine serum (FBS, Invitrogen), and maintained in a humidified incubator with 5% CO₂ at 37°C.

TPC-1 and KTC-1 human thyroid cancer cells were bought from ATCC. TPC-1 cells were maintained in high-glucose DMEM culture medium (Gibco, USA), and KTC-1 cells were maintained in F-12K culture medium (Gibco, USA), respectively, with 10% of fetal bovine serum at 37°C in a 5% CO₂ incubator.

The PTC cell lines, including TPC‐1 (differentiated thyroid carcinoma), KTC‐1 (poorly differentiated thyroid gland carcinoma) and SW1736 (thyroid gland anaplastic carcinoma), and the normal thyroid epithelial cell line (Nthy‐ori3‐1) were purchased from American Type Culture Collection (Rockefeller, MA, USA) and cultured in Dulbecco's modified Eagle’s medium (DMEM; Gibco, Grand Island, NY, USA) containing 10% FBS (Gibco), 50 U·mL⁻¹ penicillin and 50 g·mL⁻¹ streptomycin (Gibco) at 37 °C in a humidified incubator with 5% CO₂. Cells were authenticated by short tandem repeat profiling. The LV5‐GFP [lentiviral overexpression (OE)] vectors were used for lentiviral packaging, and the CST1 mRNAs were amplified and cloned into the LV5‐GFP by Sangon Biotech (Shanghai, China) to generate CST1 overexpression (OE‐CST1) vectors. In addition, according to the previous study [15 (link)], the small interfering RNAs (siRNAs) targeting CST1 (Gene ID: 1469 NM_001898.2) were synthesized by GenePharma (Suzhou, China), and the detailed sequence information for siRNA to knock down CST1 is listed in Table 1. The earlier vectors were delivered into PTC cells by using the Lipofectamine RNAiMAX (Invitrogen, Carlsbad, NY, USA) based on the protocols provided by the producer. The transfection efficiency of the earlier vectors was verified by the following real‐time quantitative PCR (qPCR) analysis.

Human PTC cells (KTC-1, BCPAP, K1, TPC-1, IHH-4, NPA87) and normal thyroid cells (Nthy-ori3-1) were purchased from the American Type Culture Collection (ATCC, USA). Cells were cultured as documented by the manufacturer at the condition of 37°C and 5% CO₂. Short tandem repeat DNA profiling was adopted to reauthenticate the cells prior to usage.

The PTC cell lines TPC-1 and K1, PDTC cell line KTC-1, and ATC cell line CAL-62 used in this study were purchased from the American Type Culture Collection (ATCC). All cells were cultured in the 37°C and 5% CO₂ culture environment, and in specific mediums (Gibco, USA) suggested by ATCC with 10% fetal bovine serum (FBS).