The study demonstrated that 41% of osteosarcoma patient loss of LKB1 protein expression was due to posttranslational regulation by SIRT1 deacetylase, but not due to genetic anomalies or loss of LKB1 mRNA levels (24), suggesting that decreases in LKB1 expression could also be important for osteosarcoma formation. This evidence concerns the gene STK11 and osteosarcoma.