METHODS: RESULTS: We detected 7B2 immunoreactivity in 19 of 22 neuro-endocrine lung tumours (with values ranging from less than 5 to 555 fmol/mg wet weight tissue), CCB immunoreactivity in 20 of 22 tumours with neuro-endocrine features (with values ranging from less than 5 to 19,875 fmol mg wet weight tissue) and
gastrin releasing peptide immunoreactivity in 10 of 22 neuro-endocrine lung
tumors (with values ranging from less than 5 to 11,132 fmol/mg wet weight tissue). Immunoreactive 7B2 and CCB were detected neither in tumours with non-endocrine features, nor in the four normal lung specimens. Differing molecular weight forms of immunoreactive 7B2 in two bronchial
carcinoids associated with the
ectopic ACTH syndrome showed a predominant signal corresponding to a molecular weight of 22 kDa; in addition, a second signal of 19 kDa was also present. The differing molecular weight forms of immunoreactive
ACTH related
peptides in the five tumours responsible for the
ectopic ACTH syndrome showed, in addition to ACTH1-39, the constant presence in variable proportions of
corticotrophin-like intermediary lobe
peptide (or ACTH18-39). The differing molecular weight forms of immunoreactive
GAWK showed heterogeneous results with materials eluting at Kav of 0, 0.3 and 0.4 respectively. In the three bronchial
carcinoids studied, two immunoreactive
gastrin releasing peptide molecular weight forms were always found at Kav of 0.5 and 0.85 corresponding to
gastrin releasing peptide and its fragment 14-27 respectively.
CONCLUSION: