CCKBR and medullary thyroid gland carcinoma: In particular Reubi and coworkers have demonstrated that more than 90% of medullary thyroid carcinomas and ovarian stromal carcinomas, and more than 50% of astrocytomas and small cell lung carcinomas, are CCK2R-positive.[2] In contrast, non-amidated forms such as glycine-extended gastrin (Ggly), which are not recognised by the CCK2R, stimulate proliferation in the normal colorectal mucosa.