Examination of expression patterns of WNT signaling in the human fallopian tubes

Abstract The fallopian tubes are a pair of tubes extending between the uterus and ovaries, and are examined in four different anatomical sections. Each anatomical section is known to have different structural features and cell distributions. Wnt signaling pathway ligands, which are important in the control of developmental events, stem cells and cell behaviors, are released from the fallopian tubes under physiological and pathological conditions. In this study, the purpose was to perform quantitative analysis of canonical Wnt pathway ligands in different anatomical regions of human fallopian tubes, evaluate the Wnt3a ligand in immunohistochemical terms, and to show that these different sections are not affected by pathologies in light microscopy. For this purpose, unilateral fallopian tube tissues taken from 5 patients in secretory phase were divided into three regions as proximal, distal and ampulla. The reverse transcriptase quantitative PCR method revealed the expression of 7 of 8 different canonical Wnt pathway ligands in Fallopian tubes. Wnt1, Wnt3, Wnt3a, Wnt8b, Wnt10a, and Wnt10b ligands showed higher expression levels in fimbriae, whereas Wnt3a expression was significantly lower in the proximal section than in the distal and ampulla sections. When Wnt3a ligand was evaluated immunohistochemically, it was observed to be intensely localized in tube epithelium and lamina propria. The presence of Wnt ligands suppressed in secretory phase by fallopian tubes shows the importance of this pathway in tube homeostasis. It was shown that Wnt ligands can be considered as protective factors of stemness in fallopian tubes.