2.1 Cell culture and animal models
The human melanoma cell lines A375, SK-Mel-28, and HMVII and the human
non-small cell lung cancer cell line A549 were obtained from Procell
Life Science & Technology Co., Ltd.; A375, SK-Mel-28, and A549 were
cultured in standard Dulbecco’s modified Eagle’s medium or RPMI-1640
(Bioskan) supplemented with penicillin (Bioskan), streptomycin
(Invitrogen), and FBS (Sigma‒Aldrich) at 37 °C in a 5%
CO2 atmosphere; and HMVII was cultured in Ham’s F-10
Nutrient Mixture (Giboco) supplemented with 10% FBS [Sigma‒Aldrich]
at 37 °C with 5% CO2. When the cells reached
~ 80% confluence, they were used for in vitro and in
vivo experiments.
A375 and HMVII tumor xenografts were induced in 4- to 5-week-old female
athymic nude mice (Beijing Vital River Laboratory Animal Technology Co.,
Ltd.) via the injection of 1 × 106 cells (suspended in
100 μL of PBS) into the underarm. For the SK-Mel-28 and A549 cell
models, cells were suspended in 100 μL of a 1:1 mixture of PBS and
Matrigel (BD Biosciences), and the animals were used for in vivo
experiments ∼3 weeks after implantation when the tumors reached
in diameter. Human melanoma PDX models were generated by Department of
Renal Melanoma, Peking University. All animal experiments were completed
in accordance with the relevant guidelines and regulations of Beijing
Cancer Hospital.