P4HB and gastric cancer: To investigate the presence of these proteins on the cell surface of gastric cancer cells, we used antibodies against Hsp40, Hsp60, Hsp70, Hsp90, Hsc70, PDI, ERp57 and integrins β1, β2, and β3 for epifluorescence (Fig 3A and 3B) and flow cytometry analysis (Fig 3C).