Detection of cell cycle arrest markers such as P16 and P21 and senescence-associated secretory phenotype (SASP) components such as interleukin-6 (IL-6) and interleukin-8 (IL-8) in neuronal or glial cell populations support an association between cellular senescence and disease progression in ALS. This evidence concerns the gene CXCL8 and amyotrophic lateral sclerosis.