Protein kinase C alpha is specifically linked to activation of PLD1 (Kim et al, 1999; Cockcroft, 2001) and PLD2 (Chen and Exton, 2004); results show that a PKCα link to PLD is active in cell lines derived from both normal and tumourigenic epithelia, including P4E6 cells derived from an early tumour. The gene discussed is PRKCA; the disease is neoplasm.