Ornithine decarboxylase gene is overexpressed in colorectal carcinoma.
OBJECTIVE
To investigate the ornithine decarboxylase (ODC) gene expression in colorectal carcinoma, ODC mRNA was assayed by RT-PCR and ODC protein was detected by a monoclonal antibody against fusion of human colon ODC prepared by hybridoma technology.


METHODS
Total RNA was extracted from human colorectal cancer tissues and their normal counterpart tissues. ODC mRNA levels were examined by RT-PCR. ODC genes amplified from RT-PCR were cloned into a prokaryotic vector pQE-30. The expressed proteins were purified by chromatography. Anti-ODC mAb was prepared with classical hybridoma techniques and used to determine the ODC expression in colon cancer tissues by immunohistochemical and Western blotting assay.


RESULTS
A cell line, which could steadily secrete anti-ODC mAb, was selected through subcloning four times. Western blotting reconfirmed the mAb and ELISA showed that its subtype was IgG2a. RT-PCR showed that the ODC mRNA level increased greatly in colon cancer tissues (P<0.01). Immunohistochemical staining showed that colorectal carcinoma cells expressed a significantly higher level of ODC than normal colorectal mucosa (98.6+/-1.03% vs 5.26+/-5%, P<0.01).


CONCLUSIONS
ODC gene overexpression is significantly related to human colorectal carcinoma. ODC gene expression may be a marker for the gene diagnosis and therapy of colorectal carcinoma.
Hu
Hai-Yan
HY
Experimental Center of Medical Molecular Biology, School of Medicine, Shandong University, Jinan 250012, Shandong Province, China.
Liu
Xian-Xi
XX
Jiang
Chun-Ying
CY
Lu
Yi
Y
Liu
Shi-Lian
SL
Bian
Ji-Feng
JF
Wang
Xiao-Ming
XM
Geng
Zhao
Z
Zhang
Yan
Y
Zhang
Bing
B
D000818:Animals; D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D009955:Ornithine Decarboxylase / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*
D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; D009955:Ornithine Decarboxylase