Plasma Levels of TKL-40 Glycoprotein: Prognostic Biomarker in Melanoma?
Posted: Monday, November 18, 2019
Measured increasing plasma YKL-40 levels appear to be associated with reduced survival in patients with melanoma; however, YKL-40 is unlikely a causal factor of the disease because genetically predicted high plasma YKL-40 levels did not appear to be associated with survival. Stig E. Bogesen, MD, PhD, DMSci, of the University of Copenhagen, and colleagues propose that plasma YKL-40 levels are correlated with mortality but not a causal factor. The report was published in the European Journal of Cancer.
To test whether measured and genetically predicted high plasma levels of YKL-40—a secretory glycoprotein associated with inflammation and tissue remodeling—were associated with increased mortality, the investigators studied two cohorts with a total of 4,031 patients with melanoma: 2,618 patients from hospital clinics and 1,413 general population patients. The researchers tested all patients for CHI3L1 rs4950928, a gene that is highly predictive of lifelong plasma YKL-40 levels, and measured plasma YKL-40 levels in 2,165 patients.
Age- and sex-adjusted hazard ratios for death among patients in the hospital melanoma cohort with measured plasma YKL-40 levels in the 96th to 100th percentile were 1.52 versus 1.07 in the 1st to 95th percentile and per 10-percentile increases. The effects were most pronounced among patients with localized melanomas.
The C allele of the CHI3L1 rs4950928 genotype was associated with increasing plasma YKL-40 levels in 32% of patients in the hospital cohort and 43% of the general population cohort (P < .0001). Among the combined cohorts, the multifactorial adjusted ratios for the increases were 1.04 and 0.98 for measured and genetically predicted plasma YKL-40 levels, respectively.
“Thus, our results indicate that measured increasing plasma YKL-40 is a marker and less likely to be a cause of increased mortality in patients with melanoma. These are novel findings,” the study authors concluded.
Disclosure: The study authors reported no conflicts of interest.