MKI67 and colorectal carcinoma: We used Ki67 as a positive control, although Ki67 expression does not show a homogeneous pattern in all tissues (related to the spatial heterogeneity and temporal variability of hypoxia in tumors), We found that COX4I2 expression was highly consistent with Ki67 expression and that COX4I2 overexpression significantly stimulated the proliferative capacity of CRC cells.