The Peripheral Blood Expression Of Platelet GP Ibα、GPⅡb/Ⅲa And P-Selectin In Lung Cancer

Objective: Metastasis is the main cause of cancer-related death. The research showsthat the platelets are involved in the distant metastasis of tumor cells, and the interactionsof the adhesive molecules on the platelets and the ligands on the tumor cells play animportant role in the the process of tumor metastasis. So our aim is to investigate theperipheral blood expression of platelet GP Ⅰbα、GP Ⅱb/Ⅲa and P-Selectin in patients withlung cancer, and to investigate the functions of the platelets, which can provide some helpto impede tomor cells dissemination.Method: The platelet-rich plasma was isolated from patients with lung cancer andnormal volunteers in vitro, and then the expression of platelet GP Ⅰbα、GP Ⅱb/Ⅲa andP-Selectin were measured by Flow Cytometry. The expression of normal volunteers’platelet GP Ⅰbα、GP Ⅱb/Ⅲa and P-Selectin stimulated by the platelet-poor plasma ofpatients with lung cancer were measured by Flow Cytometry and Western Blot. Plateletaggregation was induced by the addition of ADP or Collagen and measured by aturbidometric platelet aggregometer at37°C with a stirring speed of1000rpm.Results: The expression of platelet GP Ⅰbα、GP Ⅱb/Ⅲa and P-Selectin was increasedin patients with lung cancer as compared with normal volunteers. The mean fluorescenceintensity of the platelet adesive molecules of the patients with lung cancer were GPⅠbα(13.94±2.69)、 GP Ⅱb/Ⅲa(7.67±1.89)、 P-Selectin(2.84±0.60), while the meanfluorescence intensity of the platelet adesive molecules of the normal volunteers were GPⅠbα(7.92±2.12)、 GP Ⅱb/Ⅲa(5.21±0.58)、 P-Selectin(1.42±0.24). When the normalvolunteers’ platelets were stimulated by the platelet-poor plasma of cancer patients, and wefound that the surface expression of platelet GP Ⅰbα、GP Ⅱb/Ⅲa、P-Selectin and the contentof GP Ⅰbα were increased. The ADP or Collagen induced platelet aggregations were higherin patients with lung cancer than the normal volunteers. We also found that the expression of platelet GP Ⅰbα、GP Ⅱb/Ⅲa in patients with advanced stage of lung cancer (Ⅲ-IV stage)were increased compared to those with early stage (Ⅰ-Ⅱ stage)(P＜0.01). The expression ofplatelet GP Ⅰbα、GP Ⅱb/Ⅲa and P-Selectin showed no statistically significant differenceamong all pathological types of patients with lung cancer.Conclusion:There were higher expression of platelet GP Ⅰbα、GP Ⅱb/Ⅲa andP-Selectin in patients with lung cancer than the normal volunteers, and there were somesubstance in the platelet-poor plasma of lung cancer patients which can promote thesynthesis of the platelet glycoprotein Ⅰbα. The platelets of patients with lung cancer wereprone to aggregate than the platelets of normal volunteers under the stimulation of ADPor Collagen. These findings can provide a new idea to understand the role of these plateletglycoproteins in the mechanisms of cancer cells metastasis in patients with lung cancer andtake some steps to avoid the metastasis of tumor cells.