Related Experiment Video

Updated: Jun 25, 2026

Using Mouse Mammary Tumor Cells to Teach Core Biology Concepts: A Simple Lab Module
10:39

Using Mouse Mammary Tumor Cells to Teach Core Biology Concepts: A Simple Lab Module

Published on: June 18, 2015

Tamoxifen inhibits transforming growth factor-alpha gene expression in human breast carcinoma samples treated with

S J Conde1, R A M Luvizotto, M T Síbio

  • 1Division of Endocrinology and Metabolism, Department of Medical Clinic, UNESP, Botucatu, Brazil.

Journal of Endocrinological Investigation
|February 28, 2009
PubMed
Abstract

Insights

Triiodothyronine (T3) significantly increased transforming growth factor-alpha (TGF-alpha) mRNA in breast cancer cells. Tamoxifen (TAM) mitigated T3

Area of Science:

  • Endocrinology
  • Molecular Biology
  • Oncology

Background:

  • Estrogen receptor (ER) and thyroid hormone receptor expression are common in breast cancer.
  • Transforming growth factor-alpha (TGF-alpha) is a mitogenic protein implicated in cancer progression.

Purpose of the Study:

  • To investigate the effects of triiodothyronine (T3), 17beta-estradiol (E2), and tamoxifen (TAM) on TGF-alpha gene expression in primary breast cancer.
  • To explore the interactions between these treatments on TGF-alpha expression.

Main Methods:

  • Primary human breast carcinoma tissues were cultured.
  • Tissues were treated with T3, E2, TAM, or combinations thereof.
  • TGF-alpha mRNA levels were quantified via quantitative real-time PCR.

Main Results:

  • T3 treatment significantly upregulated TGF-alpha mRNA (15-fold increase).
  • Concomitant TAM treatment reduced T3-induced TGF-alpha expression (3.4-fold increase).
  • Tamoxifen alone increased TGF-alpha mRNA expression (5.3-fold increase).

Conclusions:

  • T3 is a more potent inducer of TGF-alpha mRNA than E2 in breast cancer primary cultures.
  • TAM exhibits a mitigating effect on T3-induced TGF-alpha upregulation.
  • TAM alone can induce TGF-alpha, suggesting a potential mitogenic role independent of E2, possibly influenced by ER subtypes.

More Related Videos

Studying TGF-β Signaling and TGF-β-induced Epithelial-to-mesenchymal Transition in Breast Cancer and Normal Cells06:54

Studying TGF-β Signaling and TGF-β-induced Epithelial-to-mesenchymal Transition in Breast Cancer and Normal Cells

Published on: October 27, 2020

Synthesis and Characterization of an Aspirin-fumarate Prodrug that Inhibits NFκB Activity and Breast Cancer Stem Cells13:38

Synthesis and Characterization of an Aspirin-fumarate Prodrug that Inhibits NFκB Activity and Breast Cancer Stem Cells

Published on: January 18, 2017

Related Concept Videos

TGF - β Signaling Pathway01:16

TGF - β Signaling Pathway

The TGF-β signaling pathway regulates cell growth, differentiation, adhesion, motility, and development. TGF-β ligands that induce TGF-β signaling are synthesized in their latent form. Several proteases or cell surface receptors such as integrins act upon the latent form, releasing the active ligand. There are three types of mammalian TGF-βs: (TGF-β1, TGF-β2, and TGF-β3) that bind as homodimers or heterodimers to TGF-β receptors. The TGF-β receptors are of three kinds RI, RII, and RIII. The RI...
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase01:11

Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase

Genetic polymorphisms in drug targets have emerged as critical determinants of interindividual variability in drug response and toxicity. Pharmacogenomic investigations increasingly focus on identifying these variations to personalize and optimize therapeutic interventions. A drug target may be a receptor, enzyme, or signaling protein involved in pharmacologic responses or disease-related pathways. While early pharmacogenetic studies focused primarily on drug metabolism, current research...
Targeted Cancer Therapies02:57

Targeted Cancer Therapies

The targeted cancer therapies, also known as “molecular targeted therapies,” take advantage of the molecular and genetic differences between the cancer cells and the normal cells. It needs a thorough understanding of the cancer cells to develop drugs that can target specific molecular aspects that drive the growth, progression, and spread of cancer cells without affecting the growth and survival of other normal cells in the body.
There are several types of targeted therapies against specific...
Synthesis and Regulation of Thyroid Hormones01:20

Synthesis and Regulation of Thyroid Hormones

Low blood levels of the thyroid hormones — triiodothyronine (T3) and thyroxine (T4) — signal the hypothalamus to release the thyrotropin-releasing hormone (TRH). TRH then reaches the pituitary gland and stimulates the release of thyroid-stimulating hormone(TSH) into the bloodstream.
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The iodine is then...