In this study, we revisit the relationship between RPSA and the 67 kDa component of the 67LR by using different cellular fractionation methods to characterize the immunoreactive components corresponding to 67LR in colorectal cancer cells in combination with mass spectrometry analyses to define the identity of the 37 and 67 kDa immunoreactive protein-related peptides. Here, RPSA is linked to colorectal cancer.