Abstract 15P
Background
Estrogen plays a pivotal role in the development of breast cancer. Previous studies have shown that estrogen enhances cell proliferation via regulating its target gene expression in human breast cancer MCF-7 cell line. Although the effect of estrogen on the carcinogenesis in breast, the effects of pregnenolone (PG), an inactive precursor of estrogen, on MCF-7 cells or breast cancer have not been adequately explored. PG is a precursor in the biosynthesis of most of the steroid hormones containing estrogen. This investigation aimed to evaluate the effects of PG on cell proliferation and cell cycle-related protein expression.
Methods
We used Michigan Cancer Foundation-7 cell (MCF-7 cell) line, to assess the impact of PG on the carcinogenicity of breast cancer cells. We examined cell proliferation, survival rate and mobility using Bromodeoxyuridine, MTT assay and western blot. To reveal the mechanism of PG, we performed RNA seq after treatment of PG in the MCF-7 cells and transfection using siRNA of estrogen receptor and ERE luciferase vector.
Results
PG increased cell proliferation, viability, mobility, and the expression of proteins associated with the cell cycle, such as CDK2, CDK4, and Cyclin D1. We elucidated the carcinogenic mechanism of PG. Through protein-ligand docking energy analysis, we measured the affinity of PG for estrogen receptors (ERs), showing a high affinity for ERα similar to E2. When treated with cyanine 5-conjugated with PG (Cy5-PG), we observed that PG entered the cells within five minutes. Then, activated ERα entered the nucleus, bound to ERE-promoters, and significantly increased the expression of target genes associated with cell proliferation and carcinogenicity, such as pS2 and Ki-67. These results indicate that PG increases the expression of target genes through ERα and thereby affects the carcinogenicity of breast cancer cells.
Conclusions
Our results demonstrate that PG can have a significant impact on the proliferation and migration of ERα-positive breast cancer cells through ERα. Furthermore, the sustained high concentration of PG, unlike E2 which rapidly decreases after menopause, is strongly associated with the development of breast cancer. Therefore, PG has the potential to serve as a risk factor and diagnostic biomarker for breast cancer.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
281P - 10-year treatment outcome of prostate cancer patients with 3D conformal radiation: Experience of a single cancer institution in Iran
Presenter: Reyhane Bayani
Session: Poster Display
Resources:
Abstract
282P - Predictors of outcomes in patients with clinically lymph node-positive prostate cancer after definitive radiotherapy
Presenter: Jae-Sung Kim
Session: Poster Display
Resources:
Abstract
283P - Radiotherapy utilization rate and treatment patern of protate cancer at Cipto Mangunkusumo Central General Hospital (RSCM): What we learn from pre-pandemic era
Presenter: Riyan Apriantoni
Session: Poster Display
Resources:
Abstract
284TiP - CYCLONE 3: A phase III, randomized, double-blind, placebo-controlled study of abemaciclib in combination with abiraterone plus prednisone in men with high-risk metastatic hormone-sensitive prostate cancer
Presenter: Nobuaki Matsubara
Session: Poster Display
Resources:
Abstract
292P - Comparative characteristics of early cervical cancer diagnosis methods for Tashkent women
Presenter: Gulnoza Goyibova
Session: Poster Display
Resources:
Abstract
293P - Carboplatin in locally advanced cervical cancer treated with chemoradiation: An alternative to cisplatin
Presenter: Natalia Isabel Valdiviezo Lama
Session: Poster Display
Resources:
Abstract
294P - Concurrent chemoradiation with cisplatin every 3 weeks in locally advanced cervical cancer: A single arm phase II clinical trial
Presenter: Long Nguyen
Session: Poster Display
Resources:
Abstract
295P - A prospective study of dose escalated simultaneous integrated boost in node-positive cervical cancer
Presenter: Ritusha Mishra
Session: Poster Display
Resources:
Abstract
296P - Safety, efficacy, and immunogenicity of therapeutic vaccines for patients with high-grade cervical intraepithelial neoplasia (CIN 2/3) associated with human papillomavirus: A systematic review
Presenter: Caroline Amélia Gonçalves
Session: Poster Display
Resources:
Abstract
297P - The utilization rate of radiotherapy and chemotherapy for cervical cancer in Indonesia: Optimal versus actual, how far the gap?
Presenter: Charity Kotambunan
Session: Poster Display
Resources:
Abstract