Ghaffar et al (2003) have bolstered this possibility by detecting frequent LKB1 loss in the progression of the premalignant lesion atypical adenomatous hyperplasia (AAH) towards frank invasive. Developmentally, LKB1 is expressed in foetal lung and ubiquitously expressed in adult bronchial mucosa, underscoring its importance in normal lung physiology and development (Luukko et al, 1999). Step by step, pieces of a puzzle assemble to document both the importance of LKB1 to the normal lung and its high frequency of aberrancy in cancer. This evidence concerns the gene STK11 and cancer.