c, Immunohistochemical analysis of paraffin-embedded sections of breast tissue from patient 441 shown in b. Adjacent sections are stained with pre-immune 843 rabbit serum (left column), 843 anti-Beclin 1serum (middle column) and anti-cytokeratin (right column). Top row shows low power view of region of breast containing tumour (T) and normal mammary epithelial duct (N). Middle row shows higher power view of normal mammary epithelial duct. Bottom row shows higher power view of tumour. Scale bars, 1 mm. 