As a previous report suggested that the CS56 monoclonal antibody preferentially binds to 6-O-sulfated CS33 and a recent gene knock-in experiments revealed that CHST3-mediated 6-O-sulfation exclusively induced strong CS56 binding34, accordingly, our CS56 staining data partially reflect the quantity of CS and suggests that CHSY1 may mediate the increases of 6-O-sulfated CS in human glioma. The gene discussed is CHSY1; the disease is central nervous system cancer.