Epidermal growth factor receptor mRNA in peripheral blood of patients with pancreatic, lung, and colon carcinomas detected by RT-PCR.
The epidermal growth factor receptor (EGFR) is overexpressed in many solid tumors. An RT-PCR assay was used to detect EGFR mRNA in the blood of 43 patients with pancreatic, lung (NSCLC), colon, and renal carcinomas. After an initial serum tube was drawn to clear the line of detached epithelial cells, a 3 ml sample of EDTA-anticoagulated blood was collected from each cancer patient and healthy control. Total RNA was isolated from each sample and from cancer cell lines. After reverse transcription using specific priming, outer and nested primers for EGFR were employed for cDNA amplification. RNA integrity was confirmed with RT-PCR amplification using beta2-microglobulin primers. PCR products were electrophoresed on agarose gels containing ethidium bromide and visualized. The assay was validated using Southern blotting and was capable of detecting a lower limit of 100 fg of total RNA from the A431 cell line. EGFR-positive cells were detected in 3/10 (30%) non-small cell lung cancer patients, 2/11 (18%) pancreatic cancer patients, and 2/16 (12.5%) colon cancer patients, but in 0/6 (0%) patients with renal carcinoma (16% of solid tumor patients overall). All 23 healthy controls were negative. This study is the first to apply RT-PCR for the detection of EGFR mRNA in the peripheral blood of patients with pancreatic and renal carcinomas, and it lends further support for the use of EGFR mRNA as a marker of CTCs in the blood of patients with certain types of solid tumors.
Clarke
Loren E
LE
The Pennsylvania State University College of Medicine/Hershey Medical Center, Hershey, PA 17033, USA. lclarke816@aol.com
Leitzel
Kim
K
Smith
Jill
J
Ali
Suhail M
SM
Lipton
Allan
A
D000230:Adenocarcinoma / Q000097:blood; D014408:Biomarkers, Tumor / Q000097:blood*; D015139:Blotting, Southern; D002289:Carcinoma, Non-Small-Cell Lung / Q000097:blood*; D002292:Carcinoma, Renal Cell / Q000097:blood*; D003110:Colonic Neoplasms / Q000097:blood*; D004587:Electrophoresis, Agar Gel; D066246:ErbB Receptors / Q000235:genetics*; D006801:Humans; D007680:Kidney Neoplasms / Q000097:blood*; D008175:Lung Neoplasms / Q000097:blood*; D009360:Neoplastic Cells, Circulating; D010190:Pancreatic Neoplasms / Q000097:blood*; D012333:RNA, Messenger / Q000097:blood*; D012334:RNA, Neoplasm / Q000097:blood*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D014407:Tumor Cells, Cultured / Q000737:chemistry
D014408:Biomarkers, Tumor; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D066246:ErbB Receptors