- Peptide products of the neurotrophin-inducible gene vgf are produced in human neuroendocrine cells from early development and increase in hyperplasia and neoplasia. Rindi, G., Licini, L., Necchi, V., Bottarelli, L., Campanini, N., Azzoni, C., Favret, M., Giordano, G., D'Amato, F., Brancia, C., Solcia, E., Ferri, G.L. J. Clin. Endocrinol. Metab. (2007)