SOD1 and neoplasm: After 48 h of incubation time, cell proliferation was investigated and the results indicated that chitosan-copper complexes selectively inhibited HeLa and 293 tumor cell line proliferation, but there was no inhibition in the growth of HLF.79 Another research observed that chitooligosaccharides (a polymerization degree of 2–8) could decrease tumor angiogenesis and exhibited antioxidant activity by augmenting the SOD activity in Kunming mice that were implanted with human breast cancer cells, dose dependently.80