[Relationship between extracellular matrix and progressive growth of malignant tumor]

To explore the role of extracellular matrix proteins in tumor cell invasion and metastasis.

Mouse pulmonary adenocarcinoma cell line LA795 and human nasopharyngeal carcinoma cell line CNE-2Z were implanted subcutaneously and under the renal capsule in T739 and nude mice, respectively. At different time intervals, expression of fibronectin(FN), laminin(LN) and type IV collagen(IV C) in the tumor extracellular matrix and in tumor adjacent tissues was examined by indirect immunoperoxidase and immunofluorescence techniques. In addition, various in vitro methods (random migration of tumor cells in agarose droplet, growth of tumor cell colonies in soft agar, dot blotting, etc.) were used to analyse the effect of exogenous LN, FN or IV C.

As tumor grew, the expression of FN, LN or IV C increased and presented different distribution patterns. Exogenous FN, LN and IV C enhanced the mobility of tumor cells and the growth of the tumor cell colonies.

The distribution difference and the changes in synthesis and degradation of the extracellular matrix proteins are valuable in predicting the biologic behaviour. Tumor implanted under the renal capsule of mice offers a better experimental model to study the relationship between extracellular matrix and tumor cell invasion.