Distinct patterns were observed: in 56.25% of the samples (9 out of 16), both monomeric and oligomeric forms of cystatin C were detected; in 31.25% of the samples (5 out of 16), the monomeric form predominated; and in the remaining 12.50% (2 out of 16), oligomeric forms were the major species (Supplementary Fig. 1c), suggesting that oligomeric cystatin C exists in tumor tissues, albeit with variable abundance across samples. The gene discussed is CST3; the disease is neoplasm.