HASPIN and cancer: ConsideringHASPIN’s prominence in mitotic progression, we speculated thatthe high GSG2 expression allows the activemitosis required for cancer’s abnormal cell proliferation.However, GSG2’s expression levelalone would be an insufficient mitotic activity indicator, as GSG2 is continuously expressed throughout thecell cycle.3 Therefore, we defined an activemitosis signature as a set of 126 mitotic genes (Table S5) whose expression levels were significantly elevatedand correlated with GSG2 expression inpan-cancers.