CCL2 and peripheral neuropathy: For example, single nucleotide polymorphisms (SNPs) in the PKNOX1 gene are not only associated with an increased risk of painful peripheral neuropathy (Magrangeas et al., 2016; Zhou X. et al., 2023), but may also influence BIPN by regulating the transcription of the pain biomarker monocyte chemoattractant protein-1 (Zhang and De Koninck, 2006).