Differences in extracellular matrix composition and its role in invasion in primary and secondary intracerebral malignancies

The most common malignant primary brain tumor is glioblastoma which infiltrates the peritumoral brain, while secondary brain metastases are well demarcated malignancies. Previous research has proved the pivotal role of the changes in the extracellular matrix (ECM) in cancer cell invasion.The mRNA expression of 40 ECM molecules was determined using qRT-PCR in 54 fresh-frozen glioblastoma and brain metastasis samples. Seventy-two samples were used to determine the levels of 20 ECM proteins.The mRNA and protein expression pattern of the studied tumors differs greatly. Linear discriminant analysis of mRNA expression identified samples based on their mRNA expression profile with 92.3% probability and highlighted the role of some molecules as their level greatly influenced sample identification.Different tumor types with different invasiveness differ in the composition of their ECM and this can be used to identify samples. Furthermore, some ECM molecules greatly contribute to tumor invasiveness and could be targets of anti-invasive oncotherapy.