Diagnostic Study Of MOC-31 And HBME-1 In Pleural Effusion Of Patients With Lung Cancer

ObjectiveLung cancer has a high incidence rate in our country,and the most of them can cause pleural effusion of cancer.At present, cytology is the standard method of diagnosing malignant pleural effusion,but the sensitivity is only 58% according to literatures.A part of the patients that they had conspicuous metastasis or recidivation of neoplasm are negative for cytology yet.Conventional cytologic diagnosis is based on cytomorphology, as the cancer cells are free floating and hyperplasia for a few generations without the tie and support of the tissues and organs, they have lost their morphologic specifity. As a result ,the sensitivity of purely diagnosis based on cytology is very low. Especially in the early times, the atpia of the cancer cells are not very obvious, the differentiation of which and reactive mesothelial cells is really a vexing problem. Establishing an a set of scientific and effective diagnostic method is a effective way to improve the positive rate of the diagnosis of lung cancer. And it is also the key to improve the survival rate and cure rate of the patients with lung cancer.Our study makes lung cancer of our major object, and is based on pleural effusion. We apply RT-PCR on examining the genetic expressing of MOC-31mRNA in the cancer cells. We apply immunocytochemistry on examining the position expression of MOC-31 in the cancer cells. We discuss new way of diagnosing pleural effusion of lung cancer and evaluate the clinic value of single index and consociation of several index applying on the diagnosis of lung cancer.Methods100 pleural effusion was collected from the first clinic hospital of china medical college. There are 56 pleural effusion of primary lung cancer and 44 nonmalignant pleural effusion.1. Immunocytochemistry (1)Collecting cancer cells in the pleural to make paraffin cell blocks.(2)Cutting paraffin sTction. Applying on immunocytochemistry staining.2. Reverese Transcription Polymerase Chain Reaction,RT-PCR(1)Exacting total mRNA from cancer cells.(2)Total mRNA was convert to cDNA and performed PCR.(3)The PCR-amplified products underwe electrophoresis on agarose gel and analysis.Results1.Immunocytochemistry examination of MOC-31 :the positive rate of the pleural effusion of lung cancer is 71.4%(40/56), which is obviously higher than the positive rate of nonmalignant pleural effusion, which is 0%(0/44).2. Immunocytochemistry examination of HBME-1: the positive rate of the pleural effusion of lung cancer is 19.6%(11/56), which is obviously low than the positive rate of nonmalignant pleural effusion, which is 93.2% (41/44) (χ~2=53.4,P<0.01).3. RT-PCR examination of MOC-31mRNA:the positive rate of the pleural effusion of lung cancer is 91.1%(51/56),which is obviously higher than the positive rate of nonmalignant pleural effusion, which is 9.1%(4/44) (χ~2=66.9,P<0.01) ;There is no relationship between the positive rate of MOC-31 mRNA of the pleural effusion of lung cancer pathological patterns (χ~2= 1.66, P> 0.05).4. The best diagnostic strategy is RT-PCR examination of MOC-31 mRNA with immunocytochemistry staining of HBME-1 ,which achieved sensitivity and accuracy is 96.4% and 93.0% respectively.DiscussMOC-31 is also called human pancarcinoma-associated epithelial glycoprotein-2 (EGP-2), which is a very reliable marker in the differentiation of epithelium. Intheories, MOC-31 only expresses in the epithelial cells, but not in the unepithelial cells. As a result, detecting of MOC-31 is helpful in diagnosis of the origin of the cells in the pleural effusion. Benign pleural effusion only includes cells and mesothelial cells, but not epithelial cells. So if the cells in the pleural effusion express MOC-31, which means epithelial cancer cells metastase. Immunocytochemical techniques have now become widely used in cytopathology for the demonstration of a large number of various antigens in effusion cell block as an aid in differentiating carcinoma cells from reactive atypical mesothelial cells.MOC-31 is the marker of epithelial cells and HBME-1 is the marker of mesothelial cells, our study used such kind of two complementary monoclone antibodies to detect the cancer cells in the pleural effusions. Parallelism test analysis of the MOC-31 and HBME-1 concerns that the improving of expressing rate of diagnosis, and the sensitivity and accuracy can reach to 82.1%(46/56) and 86.0%(86/100).Applying RT-PCR in detecting the cancer cells in the pleural effusions achieves the goal to early diagnosis. This method is highly sensitive, which can detect 1 target cell in 10~6-10~7 cells. The result of our study concern that M0C-31mRNA is a very important diagnostic marker and referencial marker in diagnosis of cancer cells micrometastase.In this study, applying immunocytochemistry to detect MOC-31 and HBME-1 and RT-PCR to detect MOC-31 mRNA and protein content of MOC-31 can improve the sensitivity of diagnosis of malignant pleural effusions effectively. Solo applying those methods, the highest sensitivity is MOC-31 mRNA which achieves 91.1%, and consociation applying any two of the three methods, the best sensitivity and accuracy consociation is immunocytochemistry of HBME-1 and MOC-31 mRNA which achieves 96.4%(54/56)> 93.0%(93/100). This consociation has clinical value in diagnosis of pleural effusion with lung cancer. And it can be taken as an important method in studying the early micrometastase of cancer cells, which is has a promising applicant future.Conclusion1. The application of immunocytochemistry on the examination of MOC-31 and HBME-1 and RT-PCR on the examination of MOC-31 can effectively improve the positive rate of diagnosing pleural effusion of lung cancer.2.RT-PCR examination of MOC-31 mRNA and immunocytochemistry examination of HBME-1 can achieve best sensitivity and accuracy(96.4% and 93.0%),which has important clinical applying value of diagnosing pleural effusion of lung cancer.