Prolonged cell survival in xenografts from human digestive endocrine tumors

#113

Introduction: Gastroenteropancreatic endocrine tumors have the capacity to achieve very large tumor masses despite usually very low proliferative rates. This suggests that neoplastic endocrine cells may have long life spans, implying the development of specific mechanisms able to promote cell survival.

Aim(s): In a first attempt to test this hypothesis, we decided to study the duration of survival of neoplastic endocrine cells obtained from fresh human tumor tissue and transplanted into the nude mouse.

Materials and methods: Fresh tissues were obtained from eight tumors (six primary, two metastatic) obtained from seven patients enrolled after informed consent. There were two pancreatic tumors (one glucagon-positive, one gastrinoma); four were of intestinal origin (all were serotonin positive; one was associated with the carcinoid syndrome); one was a mesenteric lymph node metastasis from a primary tumor located in a Meckel diverticulum. The glucagon-positive pancreatic tumor was classified as a well-differentiated tumor of benign behavior; all other cases were well-differentiated endocrine carcinomas. Immediately after surgical resection, small pieces (2x2x2 mm) of fresh tumor tissue were transplanted subcutaneously between the scapulae under anaesthesia into 4- to 5-week-old female Balb/c nude mice (eight mice per tumor). Animals were sacrificed one, two, four and six months after grafting; tumor tissues were either fixed in buffered formalin or frozen in liquid nitrogen for further histological and immunohistochemical techniques. When possible, tumor samples derived from grafted tumors were retransplanted.

Conference: 7th Annual ENETSConcerence (2010)

Presenting Author: Poncet G

Authors: Poncet G, Lépinasse F, Hervieu V, Hommell J, Walter T,

Keywords: human grafted tumors, cell survival, morphological differentiation,