PB0716 - Cancer cell cluster in carcinomatosis associated with fibrin fiber

Background: The expansion of carcinomatosis in the peritoneal cavity is poorly documented

Aims: Studying the effect of microenvironments on modified mesothelial layers hemostasis and fibrin deposit for cancer cell adhesion and dissemination.

Methods: i) Cell aggregates, isolated from human ascites, ii) fibrin networks isolated from ascites, iii) transmission and scanning electron microscopy (EM) used for cancer cell-fibrin interaction fibrin fibers analysis. iv) to document the kinetics of CT26 mice colon cancer cell in the presence of fibrin, time-lapse micro cinematography was done.

Results: i) cell aggregates stained using methylene blue and eosin dyes englobed by fibers. ii) the transmission electron microscopy of cell cluster showed the fibrin network around of the cells. These results suggest fibrin can be a skeletal structure for the cancer cell cluster integrities. iii) scanning EM showed high resolution of cancer cell-fibrin interaction. iv) In vitro study of CT26 cancer cells incubated with fibrin clot showed that cells interacted and adhered to the fibrin network. v) In addition, three levels of interaction were evidenced with micro cinematography. Firstly, a direct cell- fibrin interaction was observed in the first hours of incubation. Secondly, after 38 hours of incubation fibrin fibers were detached from clot surface cancer cell-fibrin interaction. Thirdly, after 45h s incubation, the detached fibers inhibit cancer cell-fibrin interaction, then jailing the cancer cells. Curiously, they generated cell agglomerates and formed the cell clusters.

Conclusion(s): the fibrin net generated on the peritoneum has a crucial role in cancer cell dissemination and expansion via tumor cell clusters