Mohammad Hasan Soheilifar - Research centre for molecular medicine and genetics, School of Medicine, Hamedan University of Medical Sciences, Hamedan,Iran
Abdolvahab Moshtaghian - Deputy of Research and Technology, Semnan University of Medical Sciences, Semnan, Iran
Razieh Amini - Research centre for molecular medicine and genetics, School of Medicine, Hamedan University of Medical Sciences, Hamedan,Iran

Introduction: PGs are glycosylated proteins with context-dependent function and are expressed in the extra cellular matrix (ECM), in the cell and on the cell surface. The expression patterns of proteoglycans (PGs) change in the gastric cancer. Gastric cancer is one of the major causes of cancer related death in the world.PGs have important roles in initiation and progression of gastric cancer. The present study aimed to investigate various functions of PGs in gastric cancer Methods: In this study we reviewed research articles published in online databases including PubMed, Science Direct, Medline, Google scholar and Scopus using relevant keywords such as: proteoglycan, gastric cancer and signaling pathways and tumorigenesis.Results: Changes in PGs expression and their functions or signaling pathways involved in gastric cancer.It has been shown in various research studies that more proteoglycans are upregulated in gastric cancer. Asporin, Biyglycan and Lumican overexpressed in gastric cancer and involved in EGFR, FAK and integrin β1-FAK signaling pathways respectively. SRPX2 promote cell migration and adhesion through FAK signaling. So it could be concluded, FAK signaling has major role in proteoglycans oncogenic functions in gastric cancer. Furthermore Versican and Syndecan-2 play important role in cancer cell migration, invasion and proliferation. Testican induce slug-mediated epithelial-mesenchymal transition in gastric cancer. On the other hand, some proteoglycans like Serglycin and Syndecan-1 are downregulated in gastric cancer but the exact role and signaling pathways that these proteoglycans involved in have not been identified yet. Although it seems that these molecules may play tumor suppressor role in gastric cancer.Conclusion: PGs expression patterns altered during gastric cancer development. Although the biological role of some PGs like serglycin is still not fully understood in gastric cancer but it has been shown that PGs act as an oncogene or tumor suppressor and involved in tumor signaling pathways through mediation of ligand/ receptor interaction and promote or inhibit cancer cells migration and invasion. In conclusion deregulated expression of PGs involved in carcinogenesis and can be used as potential biomarkers for gastric cancer diagnosis, prognosis and in cancer treatment.

Proteoglycan, Gastric Cancer, Tumorigenesis, Signalling pathways