ARSB and neoplasm: Treatment with exogenous, bioactive Arylsulfatase B (ARSB; N-acetylgalactosamine-4-sulfatase), the enzyme that removes 4-sulfate groups at the non-reducing end from chondroitin 4-sulfate (C4S), was recently shown to reduce tumor progression and improve the survival of C57BL/6J mice with B16F10 subcutaneous melanomas [6].