In summary: (1) In metastatic carcinoma CaOV-3 both ObR antagonists had an inhibitory effect on the cdk2/cyclin D1 complex, while in serous carcinoma, OVCAR-3, they had an effect only on cdk2 and cdk4 protein expression, (2) SHLA had an inhibitory effect on all the investigated signalling pathways in OVCAR-3, but only on Stat3 in CaOV-3, (3) Lan-2 had an inhibitory effect on Stat3 and ERK1/2 CaOV-3, while in OVCAR-3 it only had an effect on Akt protein phosphorylation. Here, STAT3 is linked to metastatic carcinoma.