Inhibin/activin-betaC and -betaE subunits in the Ishikawa human endometrial adenocarcinoma cell line

Abstract

Here, we show for the first time that the novel inhibin/activin-betaC and -betaE subunits are expressed in normal human endometrium and the estrogen receptor positive human endometrial carcinoma cell line Ishikawa using RT-PCR and immunohistochemical detection methods. Interestingly, the Ishikawa minus cell line (lacking estrogen receptor expression) demonstrated no to minimal expression of the betaC subunit as observed with immunofluorescence and RT-PCR, suggesting a possible hormone- dependency of this subunit in human endometrial cancer cells. Moreover, because the Ishikawa cell line minus is thought to be a more malignant endometrial cell line than its estrogen receptor positive counterpart, inhibin-betaC subunit might be substantially involved in the pathogenesis and malignant transformation in human endometrium.

Evidence of inhibin/activin subunit betaC and betaE synthesis in normal human endometrial tissue

“…The inhibin βC protein was primarily expressed in human liver and prostate [27], while inhibin/activin βE mRNA was predominantly synthesized in human liver with low levels found in heart, testis, leukocytes, and skeletal muscle [5]. Inhibin βC was previously detected by immunohistochemical methods in normal and abnormal placenta [28,29], endometrial cell lines [30,31], endometrial cancer [32], and cervical tissue [33]. Additionally, the inhibin βE is synthesized in normal and abnormal placenta [5,34,35] as well as human cervical tissue [36] and the endometrial cancer cell line Ishikawa [31].…”

Inhibin-α subunit expression in uterine endometrioid adenocarcinomas and endometrial cancer cell lines: a potential prognostic factor

“…HEC-1A and HEC-1B; Ishikawa plus and Ishikawa minus) (41,44). Several inhibin-subunits have been observed in the Ishikawa and RL95-2 cell lines by using immunohistochemical techniques (35,70,71). In this study, inhibin-· synthesis was demonstrated in several endometrial cancer cell lines by using immunohistochemical and molecular biological techniques.…”

“…The endometrial cancer cell lines Ishikawa plus (estrogen receptor positive), Ishikawa minus (estrogen receptor negative), HEC-1A, HEC-1B, and RL95-2 were obtained from ATCC (LGC Promochem GmbH, Wesel, Germany) and were grown in Quantum 263 medium (PAA, Pasching, Austria), supplemented with antibiotics at 37°C in a humidified atmosphere with 5% CO 2 as previously described (34,35).…”

Immunolabeling of the Inhibin-βA and -βB Subunit in Normal and Malignant Human Cervical Tissue and Cervical Cancer Cell Lines

“…Nonspecific binding was blocked by incubating the sections with Ultra V Block (Lab Vision) for 15 minutes at room temperature as previously described. 9,13 Thereafter, slides were incubated with inhibin-A A antibody (1:100 in dilution medium; DAKO) or inhibin-A B antibody (1:10 in dilution medium; DAKO) overnight at 4-C, followed by a 1:500 diluted Cy3-conjugated goat-antimouse antibody (Dianova, Hamburg, Germany) for 30 minutes in room temperature. The slides were finally embedded in a mounting buffer containing 4,6-diamino-2-phenylindole, resulting in blue staining of the nuclei.…”