Abstract

While the increased prevalence of venous thromboembolic events (VTE) is fully recognized in lung cancer, its pathogenesis is not fully understood. Profiling of surrogate markers of thrombosis and inflammation provides an opportunity to understand the pathogenesis of VTE. More recently, ProteinChip Array technology has provided a novel approach to profile unique biomarkers in cancer patients. Protease activation in these patients results in the generation of unique biomarkers, which can be identified and monitored during the course of patient management. In a prospective, randomized, controlled study patients with inoperable lung cancer (n=100) were randomized to receive A) chemotherapy, radiation and warfarin (INR 1.5–2.5) or B) chemotherapy, radiation without warfarin (n=50). Blood samples were drawn prior to and after the second treatment cycle in both groups A and B. All samples were also analyzed for such inflammation markers as the tumor necrosis factor alpha (TNFa), CD 40 ligand (CD 40L), C-reactive protein (CRP), interleukin 1 beta (IL-1B), asymmetric dimethylarginine (ADMA) and nitric oxide (NO). In addition, prothrombin fragment F1.2 (F1.2), thrombin antithrombin complex (TAT) and functional microparticles were also measured. Proteomic profiling is widely used to identify unique biomarkers in various hemotologic disorders. Albumin was used as control proteins throughout the study. The baseline blood levels of the inflammatory markers and coagulation activation marker were increased in both the warfarin treated and control group. After the second treatment cycle, the warfarin treated group exhibited varying levels of decrease in all of the surrogate markers of coagulation activation and inflammation (13 – 15%). On the other hand, none of the warfarin treated group showed a marked increase in the TNFα, CD40L, NO, F1.2 and TAT (18–30%). No change in the IL-1B was noted in this group. However, CRP levels were markedly reduced (46%). Most of the baseline samples in both groups showed a unique biomarker peak at 11.9 kDa. The prevalence of this unique biomarker peak was decreased after the second cycle of chemotherapy and after the final course of chemotherapy, it was totally diminished. No significant differences in the down regulation of this unique biomarker were obvious in both groups. Since inflammatory markers showed a decrease (13–50%) in the warfarin treated group, whereas the non-warfarin treated group exhibited an increase (18–30%) in all markers except IL-1B, CRP and ADMA, anticoagulation down regulates these mediators. Markers of thrombin generation were also down regulated in the warfarin treated group. The identification of the unique biomarker at 11.9 kDa in both groups and its gradual down regulation eventually leading to diminution in both groups, suggests that chemotherapy and radiation treatment appear to regulate this biomarker. The levels of various inflammatory markers are upregulated in lung cancer suggesting a pathogenic role of this process in lung cancer. Warfarin down regulated the inflammatory process in contrast to the non-warfarin treated group. However, the unique biomarker at 11.9 kDa appears to be regulated by chemotherapy and radiation. The clinical relevance of these observations requires additional investigations.

Author notes

Disclosure: No relevant conflicts of interest to declare.