Nestin suppression attenuates invasive potential of endometrial cancer cells by downregulating TGF-β signaling pathway.

Amber A Bokhari,Chad A Hamilton,Sana Waheed,Tabari M Baker,Batsukh Dorjbal,Viqar Syed,Christopher M Zahn,G Larry Maxwell

doi:10.18632/oncotarget.11947

Abstract

Nestin, an intermediate filament protein and a stem cell marker is expressed in several tumors. Until recently, little was known about the expression levels and the role of Nestin in endometrial cancer. Compared to the immortalized endometrial epithelial cell line EM-E6/E7-TERT, endometrial cancer cell lines express high to moderate levels of Nestin. Furthermore, endometrial tumors and tumor cell lines have a cancer stem-like cell subpopulation expressing CD133. Among the cancer lines, AN3CA and KLE cells exhibited both a significantly higher number of CD133+ cells and expressed Nestin at higher levels than Ishikawa cells. Knockdown of Nestin in AN3CA and KLE increased cells in G0/G1 phase of the cell cycle, whereas overexpression in Ishikawa decreased cells in G0/G1 phase and increased cells in S-phase. Nestin knockdown cells showed increased p21, p27, and PNCA levels and decreased expression of cyclin-D1 and D3. In contrast, Nestin overexpression revealed an inverse expression pattern of cell cycle regulatory proteins. Nestin knockdown inhibited cancer cell growth and invasive potential by downregulating TGF-β signaling components, MMP-2, MMP-9, vimentin, SNAIL, SLUG, Twist, N-cadherin, and upregulating the epithelial cell marker E-cadherin whereas the opposite was observed with Nestin overexpressing Ishikawa cells. Nestin knockdown also inhibited, while overexpression promoted invadopodia formation and pFAK expression. Knockdown of Nestin significantly reduced tumor volume in vivo. Finally, progesterone inhibited Nestin expression in endometrial cancer cells. These results suggest that Nestin can be a therapeutic target for cancer treatment.

Highlights

Endometrial cancer is the most prevalent gynecologic cancer in the United States
Nestin expression was compared in four endometrial cancer cell lines and an immortalized endometrial epithelial cell line
Since Nestin is a stem cell marker, we examined the correlation of Nestin expression with the side population” (SP) cell percentages in EME6/E7-TERT, HEC-1B, Ishikawa, AN3CA and KLE cell lines

Summary

Introduction

Endometrial cancer is the most prevalent gynecologic cancer in the United States. When detected in early stages, these cancers have a good prognosis. In advanced stages the prognosis is generally poor [1, 2]. If cancer progresses, systemic metastasis leads to patient morbidity and mortality [2, 3]. With an aging and increasingly obese population in the United States, the incidence and mortality rate of endometrial cancer is increasing. This worsening public health problem provides a strong rationale for a better understanding of the molecular mechanisms of endometrial carcinogenesis as well as developing effective methods to treat the disease

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Results

Conclusion