SL	solar lentigo
MCP	monocyte chemoattractant protein
UVR	ultraviolet radiation
NHMs	normal human melanocytes
NHKs	normal human keratinocytes
SASP	senescence-associated secretory phenotype
IL	interleukin
SA-β-Gal	senescence-associated beta-galactosidase
PBS	phosphate-buffered saline
ELISA	enzyme immunosorbent assay
OD	optical density
MTT	3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide
TNF	tumor necrosis factor
LSM	laser scanning microscope
PAI-1	plasminogen activator inhibitor-1
POMC	proopiomelanocortin
CRH	corticotropin releasing hormone
ACTH	adrenocorticotropic hormone
MSH	melanocyte-stimulating hormone