Basic Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Oncol. Jun 24, 2019; 10(6): 222-233
Published online Jun 24, 2019. doi: 10.5306/wjco.v10.i6.222
Leptin-induced Notch and IL-1 signaling crosstalk in endometrial adenocarcinoma is associated with invasiveness and chemoresistance
Danielle Daley-Brown, Adriana Harbuzariu, Ann Anu Kurian, Gabriela Oprea-Ilies, Ruben Rene Gonzalez-Perez
Danielle Daley-Brown, Adriana Harbuzariu, Ann Anu Kurian, Ruben Rene Gonzalez-Perez, Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA 30310, United States
Gabriela Oprea-Ilies, Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA 30322, United States
Author contributions: Daley-Brown D performed majority of experiments, compiled and interpreted data, and contributed to the preparation of the manuscript; Harbuzariu A developed cell cycle assays and contributed to data interpretation. Kurian AA helped with the development of western blots, cell cycle and cytotoxic analyses. Oprea-Ilies G provided guidance for interpretation of data and clinical pathology features. Gonzalez-Perez RR conceived the project, helped with the elaboration of the hypothesis, supervised the experimental work, and contributed to the interpretation of data and preparation of the manuscript.
Supported by the National Cancer Institute at the National Institutes of Health, No. S21 MD000101, No. 5G12 MD0076021, No. G12 RR026250-03, No. NIH RR03034 1C06, No. RR18386 to Morehouse School of Medicine; the National Institute of General Medical Sciences, National Institutes of Health, No. 5T32HL103104-04 to DDB.
Conflict-of-interest statement: The authors declare to have no conflict of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Ruben Rene Gonzalez-Perez, PhD, Professor, Department of Microbiology, Biochemistry and Immunology, Morehouse School of Medicine, Atlanta, GA 30310, United States. rgonzalez@msm.edu
Telephone: +1-404-7521581 Fax: +1-404-7521179
Received: September 7, 2018
Peer-review started: September 7, 2018
First decision: October 26, 2018
Revised: March 14, 2019
Accepted: March 27, 2019
Article in press: March 28, 2019
Published online: June 24, 2019
Processing time: 291 Days and 17.2 Hours
Abstract
BACKGROUND

Obesity is a recognized risk factor for endometrial cancer (EmCa) and other cancer types. Leptin levels are significantly increased in obese individuals. Leptin-induced signaling crosstalk [Notch, Interleukin-1 (IL-1) and leptin outcome, NILCO] has been associated with breast cancer progression. This complex signaling crosstalk affects cancer cell proliferation, migration, invasion, angiogenesis, apoptosis and chemoresistance. NILCO expression was previously detected in human EmCa. However, it is unknown whether leptin regulates NILCO and alters EmCa’s response to chemotherapeutics. It is hypothesized that leptin induces NILCO and increases aggressiveness and chemoresistance in EmCa cells.

AIM

To determine whether leptin induces NILCO molecules in EmCa affecting cell proliferation, aggressiveness and chemoresistance.

METHODS

Leptin’s effects on the expression of NILCO molecules [mRNAs and proteins for Notch receptors (Notch1-4), ligands (JAG1 and DLL4) and downstream effectors (survivin, Hey2), and leptin (OB-R) and IL-1 (IL-1R tI) receptors] was examined in EmCa cells (type I: Ishikawa, and HEC-1A, and type II: An3Ca and KLE) using Real-time PCR and Western blot analysis, respectively. In addition, the effects of leptin on cell cycle, proliferation and cell invasion were determined using cytometric analysis (Cellometer Vision CBA system), MTT cell proliferation and Matrigel-based invasion assays, respectively. Inhibitors of leptin (nanoparticle-bound leptin peptide receptor antagonist-2, IONP-LPrA2), IL-1 (anti-IL-1R tI antibody) and Notch (siRNA interference RNA) were used to investigate NILCO’s effects on cell proliferation and invasion. Leptin’s effects on Paclitaxel cytotoxicity in EmCa cells was determined by the CCK8 and Cellometer-based Annexin V assays.

RESULTS

For the first time it was shown that leptin is an inducer of Notch in EmCa. Experimental data suggest that leptin induced the expression of NILCO molecules, promoted proliferation and S- phase progression, and reduced Paclitaxel cytotoxicity on EmCa cells. Leptin’s effects were higher in type II EmCa cells. The progression of this more aggressive form of the disease is associated with obesity. Remarkably, the use of the leptin signaling antagonist, IONP-LPrA2, re-sensitized EmCa cells to Paclitaxel.

CONCLUSION

Present data suggest the notion that leptin-induced NILCO could be a link between obesity and EmCa progression and chemoresistance. Most aggressive type II EmCa cells were higher sensitive to leptin, which appears to increase proliferation, cell cycle progression, aggressiveness, and chemoresistance to Paclitaxel. Therefore, leptin and NILCO could be novel therapeutic targets for type II EmCa, which does not have targeted therapy. Overall, IONP-LPrA2 has a potential as a novel adjuvant drug to enhance the effectiveness of type II EmCa chemotherapy.

Keywords: Endometrial cancer; Leptin; Notch; Interleukin-1; Notch, IL-1 and Leptin crosstalk outcome; Chemoresistance

Core tip: It’s the first time we report that leptin induces Notch expression in endometrial cancer (EmCa) cells. Moreover, leptin induction of Notch, Interleukin-1 (IL-1) and leptin outcome (NILCO) molecules was higher in type II EmCa cells that showed increased aggressiveness and resistance to Paclitaxel’s cytotoxic effects. Remarkably, the use of a leptin inhibitor, IONP-LPrA2, re-sensitizes EmCa cells to Paclitaxel that suggests targeting NILCO could be a new strategy to increase chemotherapeutic efficiency in type II EmCa that lacks targeted therapies.