Isolation of a novel human lung-specific gene, LUNX, a potential molecular marker for detection of micrometastasis in non-small-cell lung cancer.
We have isolated a novel human lung-specific gene, LUNX (lung-specific X protein), by differential-display mRNA analysis. The full-length cDNA contained 1,015 nucleotides including an open reading frame of 768 nucleotides encoding 256 amino acids. We localized the gene to chromosomal region 20p11.1-q12 by radiation hybrid mapping. Using an RT-PCR assay specific for LUNX mRNA, 35 non-small-cell lung-cancer (NSCLC) tumors and 0 of 16 normal lymph nodes were positive. Furthermore, LUNX mRNA expression was enhanced in 26 (84%) of 31 NSCLC tumors vs. corresponding cancer-free lung tissues by semi-quantitative analyses with multiplex RT-PCR. We assessed the possibility of LUNX mRNA as a molecular marker for detection of micrometastasis in dissected lymph nodes obtained from 20 patients with NSCLC tumors. LUNX mRNA was detected in 16 (80%) of 20 histologically positive lymph nodes and 21 (25%) of 84 histologically negative lymph nodes. Comparative analyses of the conventional histological examination and the RT-PCR detection assay for LUNX mRNA showed that the detection rate of metastases in lymph nodes by the RT-PCR assay was higher in 12 and consistent in 6 of the total 20 NSCLC patients. We demonstrate that the LUNX RT-PCR assay is a potential diagnostic method for detection of micrometastases in lymph nodes of NSCLC patients.
Department of Surgery and Clinical Oncology, Graduate School of Medicine, Osaka University, 2-2 Yamada-Oka, Suita City, Osaka 565-0871, Japan.
K
K
Iwao
T
T
Watanabe
Y
Y
Fujiwara
K
K
Takami
K
K
Kodama
M
M
Higashiyama
H
H
Yokouchi
K
K
Ozaki
M
M
Monden
A
A
Tanigami
D000595:Amino Acid Sequence; D001483:Base Sequence; D014408:Biomarkers, Tumor; D015152:Blotting, Northern; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000378:metabolism*; D002890:Chromosomes, Human, Pair 20; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D020869:Gene Expression Profiling; D006023:Glycoproteins; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism*; D008198:Lymph Nodes / Q000378:metabolism; D008207:Lymphatic Metastasis; D008969:Molecular Sequence Data; D009362:Neoplasm Metastasis; D016366:Open Reading Frames; D010750:Phosphoproteins; D014176:Protein Biosynthesis; D011506:Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D021101:Radiation Hybrid Mapping; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014018:Tissue Distribution
C485599:BPIFA1 protein, human; D014408:Biomarkers, Tumor; D018076:DNA, Complementary; D006023:Glycoproteins; D010750:Phosphoproteins; D011506:Proteins; D012333:RNA, Messenger