Percutaneous biopsy of a newly identified suspected lesion in the fifth thoracic vertebra revealed a metastasis with positive staining for ACTH, synaptophysin and chromogranin A.
Our previous studies have indicated that POMC gene delivery inhibited the progression and metastasis of B16-F10 melanoma via the α- melanocyte-stimulating hormone/melanortin-1 receptor (MC-1R) pathway.
This is the first case of Cushing's syndrome secondary to ectopic ACTH secretion where the presence of ACTH by immunohistochemistry and the expression of the POMC gene by RT-PCR have both been demonstrated in a breast carcinoma with metastases.
Abnormal NPP expression is involved in pathological mineralization, crystal depositions in joints, invasion and metastasis of cancer cells, and type 2 diabetes.
Overall, pituitary carcinoma metastases showed an average of 8.3 chromosomal imbalances per tumor (7 gains vs 1.3 losses), 10 in prolactin cell carcinoma metastases (7.5 gains vs 2.5 losses) and 6.5 in ACTH cell carcinoma metastases (6.5 gains vs 0 loss).
The length of POMC mRNA in MTCs (present in all 4 metastases investigated but not in 7 primary tumors) and pheochromocytomas is about 100 nucleotides more than pituitary POMC RNA.
Compared with the POMC mRNA occurring in the human pituitary gland, the size of the RNA species hybridizing to the POMC-specific probe was larger in the metastases of both of the patients investigated. cDNA complementary to mRNA from one of the metastases was cloned into pBR 322.