Molecular detection of metastatic pancreatic carcinoma cells using a multimarker reverse transcriptase-polymerase chain reaction assay

Abstract

Background: The diagnosis of pancreatic carcinoma is often associated with a poor prognosis, because most patients already have advanced disease. A highly sensitive assay to detect the progression of pancreatic carcinoma would be of significant clinical utility. The authors developed multiple tumor mRNA markers for reverse transcriptase-polymerase chain reaction (RT-PCR) to detect metastatic tumor cells in the blood and tissue of patients with American Joint Committee on Cancer (AJCC) Stage II/III or IV pancreatic carcinoma.

Methods: An RT-PCR plus Southern blot assay was used to detect mRNA of tumor markers in blood and tissues. mRNA expression of the tumor progression markers MET (hepatocyte growth factor receptor gene c-met), GalNAc-T (beta1,4- N-acetyl-galactosaminyl-transferase), and beta-hCG (beta-human chorionic gonadotropin) was evaluated in 9 pancreatic carcinoma cell lines, 13 tumor biopsy specimens, 5 nonmalignant pancreatic tissue specimens, and blood from 33 pancreatic carcinoma patients and 32 healthy donors.

Results: The detection limit of the assay was 1 rhog, 10 rhog, and 10 rhog for MET, GalNAc-T, and beta-hCG mRNA expression, respectively. The pancreatic carcinoma cell lines expressed all three mRNA markers. Of blood specimens from 17 patients with AJCC Stage IV pancreatic carcinoma, 82%, 65%, and 76% were MET, GalNAc-T, and beta-hCG mRNA positive, respectively. Of blood specimens from 16 patients with AJCC Stage II/III disease, 88% were positive for at least 1 mRNA marker.

Conclusions: A multiple molecular marker assay was developed to detect cancer cells in blood and tissue from patients with different stages of pancreatic carcinoma. The detection of cancer cells in the blood may be used as a marker of pancreatic tumor progression and may be useful in monitoring response to therapy.