MYO18B, a candidate tumor suppressor gene at chromosome 22q12.1, deleted, mutated, and methylated in human lung cancer.
Loss of heterozygosity on chromosome 22q has been detected in approximately 60% of advanced nonsmall cell lung carcinoma (NSCLC) as well as small cell lung carcinoma (SCLC), suggesting the presence of a tumor suppressor gene on 22q that is involved in lung cancer progression. Here, we isolated a myosin family gene, MYO18B, located at chromosome 22q12.1 and found that it is frequently deleted, mutated, and hypermethylated in lung cancers. Somatic MYO18B mutations were detected in 19% (14/75) of lung cancer cell lines and 13% (6/46) of primary lung cancers of both SCLC and NSCLC types. MYO18B expression was reduced in 88% (30/34) of NSCLC and 47% (8/17) of SCLC cell lines. Its expression was restored by treatment with 5-aza-2'-deoxycytidine in 11 of 14 cell lines with reduced MYO18B expression, and the promoter CpG island of the MYO18B gene was methylated in 17% (8/47) of lung cancer cell lines and 35% (14/40) of primary lung cancers. Furthermore, restoration of MYO18B expression in lung carcinoma cells suppressed anchorage-independent growth. These results indicate that the MYO18B gene is a strong candidate for a novel tumor suppressor gene whose inactivation is involved in lung cancer progression.
National Cancer Center Research Institute, Tokyo 104-0045, Japan.
Michiho
M
Nishioka
Takashi
T
Kohno
Masachika
M
Tani
Nozomu
N
Yanaihara
Yoshio
Y
Tomizawa
Ayaka
A
Otsuka
Shigeru
S
Sasaki
Keiko
K
Kobayashi
Toshiro
T
Niki
Arafumi
A
Maeshima
Yoshitaka
Y
Sekido
John D
JD
Minna
Saburo
S
Sone
Jun
J
Yokota
D002455:Cell Division / Q000235:genetics; D002892:Chromosomes, Human, Pair 22 / Q000235:genetics*; D018899:CpG Islands; D019175:DNA Methylation; D004252:DNA Mutational Analysis; D018076:DNA, Complementary / Q000235:genetics; D004273:DNA, Neoplasm / Q000235:genetics; D017353:Gene Deletion; D015870:Gene Expression; D016147:Genes, Tumor Suppressor; D006801:Humans; D019656:Loss of Heterozygosity; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology; D008969:Molecular Sequence Data; D009154:Mutation; D018995:Myosin Heavy Chains / Q000235:genetics; D014407:Tumor Cells, Cultured
D018076:DNA, Complementary; D004273:DNA, Neoplasm; D018995:Myosin Heavy Chains