TGFA and neuroendocrine neoplasm: As no significant difference was detected in any of these parameters or in islet size (data not shown), we concluded that the decreased tumor growth observed in RT2, wa-1/wa-1 mutant mice did not result from a preexisting defect in endocrine pancreatic development but rather stemmed from the functional contribution of Tgf-α to neuroendocrine tumor growth.