RESUMO
Kisspeptin receptor (Kiss1R) is an important receptor that plays central regulatory roles in reproduction by regulating hormone release in the hypothalamus. We hypothesize that the formation of heterocomplexes between Kiss1R and other hypothalamus G protein-coupled receptors (GPCRs) affects their cellular signaling. Through screening of potential interactions between Kiss1R and hypothalamus GPCRs, we identified G protein-coupled estrogen receptor (GPER) as one interaction partner of Kiss1R. Based on the recognised function of kisspeptin and estrogen in regulating the reproductive system, we investigated the Kiss1R/GPER heterocomplex in more detail and revealed that complex formation significantly reduced Kiss1R-mediated signaling. GPER did not directly antagonize Kiss1R conformational changes upon ligand binding, but it rather reduced the cell surface expression of Kiss1R. These results therefore demonstrate a regulatory mechanism of hypothalamic hormone receptors via receptor cooperation in the reproductive system and modulation of receptor sensitivity.
Assuntos
Hipotálamo/metabolismo , Complexos Multiproteicos/genética , Receptores de Estrogênio/genética , Receptores Acoplados a Proteínas G/genética , Receptores de Kisspeptina-1/genética , Animais , Hormônios/biossíntese , Hormônios/genética , Humanos , Complexos Multiproteicos/ultraestrutura , Ligação Proteica/genética , Receptores de Superfície Celular/genética , Receptores de Estrogênio/ultraestrutura , Receptores Acoplados a Proteínas G/ultraestrutura , Receptores de Kisspeptina-1/ultraestrutura , Transdução de Sinais/genéticaRESUMO
Although invasive epithelial ovarian cancer (IOC) and low malignant potential ovarian tumour (LMP) are similar, they are associated with different outcomes and treatment strategies. The current accuracy in distinguishing these diseases is unsatisfactory, leading to delays or unnecessary treatments. We compared the molecular signature of IOC and LMP cases by analysing their transcriptomic data and re-clustered them according to these data rather than the pathological dissection. We identified that FAM83D was highly expressed in IOC. To verify the role of FAM83D in the progression and metastasis, we used the isogenic ovarian cancer metastatic models, highly metastatic cells (HM) and non-metastatic cells (NM). Overexpression of FAM83D significantly promoted cell proliferation, migration and spheroid formation. This was consistent with previous data showing that high FAM83D expression is associated with poor prognosis in cancer patients. Moreover, similar to the HM cells, the FAM83D-overexpressing NM cells demonstrated stronger phosphorylation of the epidermal growth factor receptor (EGFR) and c-Raf. This indicates that the action of FAM83D is mediated by the activation of the EGFR pathway. Taken together, this report suggested that FAM83D might be an excellent molecular marker to discriminate between IOC and LMP.
