SAN FRANCISCOIn a study from Johns Hopkins University Medical School, one
third of sporadic lung adenocarcinomas were found to have the inactivated
LKB1/STK11 gene. A germ-line mutation in this gene has been shown to result in
Peutz-Jegher’s syndrome. Patients with this autosomally dominant disease have
an increased risk of developing malignancies. Montserrat Sanchez-Cespedes, PhD,
now a senior scientist at the Spanish National Cancer Center, Madrid, presented
the study at the 93rd Annual Meeting of the American Association for Cancer
Research (abstract 720).
The Johns Hopkins researchers had previously determined that there were high
rates of deletions on the short arm of chromosome 19 in lung adenocarcinoma
samples. Dr. Sanchez-Cespedes and her colleagues then used 18 highly
polymorphic microsatellite markers to identify the alteration as occurring in
the 5-Mb interval between the telomeric end and microsatellite marker D19S216,
which contains the LKB1/STK11 gene.
Analysis of 41 lung tumors selected for loss of heterozygosity at chromosome
19p revealed somatic mutations in 8 tumors, all predicting a truncated
LKB1/STK11 protein. All of the 8 mutations were found in the 24 lung
"We hope that these findings will help in the future in the diagnosis
of this tumor . . . and can be used as a target for the development of new
therapies," Dr. Sanchez-Cespedes said. The researchers are studying more
tumor specimens to increase the statistical weight of the initial findings and
plan to compare tumor samples with clinical data to determine if the LKB1/STK11
mutation is related to survival or response to therapy.