In 2015, a comprehensive analysis of the soluble and membrane embedded forms of intracellular and cell surface GRP78 revealed that GRP78 primarily exists as a peripheral protein on the plasma membrane via interaction with other cell surface and GPI-anchored proteins (SI Appendix, Fig. S1A), with endogenous GRP78 readily detected at the plasma membrane of stressed human colon cancer cells, as imaged by single molecule, superresolution total internal reflection fluorescence microscopy (68). Here, HSPA5 is linked to malignant colon neoplasm.