S100A9 and cancer: In this category, 19 proteins were identified, of which nine (P08311, P06702, P05109, P04196, O75594, P03973, P06899, Q29960, and Q95365) are involved in more than two processes: P06702 has been shown to be differentially expressed in various types of cancer such as breast, colon, liver, gastric and non-small cell lung cancer, and is crucial for promoting cancer growth by recruitment of myeloid-derived suppressor cells.