Related Experiment Video
Updated: May 14, 2026
The Soft Agar Colony Formation Assay
Published on: October 27, 2014
SPDEF functions as a colorectal tumor suppressor by inhibiting β-catenin activity
Taeko K Noah1, Yuan-Hung Lo, Allison Price
1Division of Gastroenterology, Hepatology, and Nutrition, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA.
Background & Aims:
Expression of the SAM pointed domain containing ETS transcription factor (SPDEF or prostate-derived ETS factor) is regulated by Atoh1 and is required for the differentiation of goblet and Paneth cells. SPDEF has been reported to suppress the development of breast, prostate, and colon tumors. We analyzed levels of SPDEF in colorectal tumor samples from patients and its tumor-suppressive functions in mouse models of colorectal cancer (CRC).
Methods:
We analyzed levels of SPDEF messenger RNA and protein in more than 500 human CRC samples and more than 80 nontumor controls. Spdef(-/-)and wild-type mice (controls) were either bred with Apc(Min/+) mice, or given azoxymethane (AOM) and dextran sodium sulfate (DSS), or 1,2-dimethylhydrazine and DSS, to induce colorectal tumors. Expression of Spdef also was induced transiently by administration of tetracycline to Spdef(dox-intestine) mice with established tumors, induced by the combination of AOM and DSS or by breeding with Apc(Min/+) mice. Colon tissues were collected and analyzed for tumor number, size, grade, and for cell proliferation and apoptosis. We also analyzed the effects of SPDEF expression in HCT116 and SW480 human CRC cells.
Results:
In colorectal tumors from patients, loss of SPDEF was observed in approximately 85% of tumors and correlated with progression from normal tissue, to adenoma, to adenocarcinoma. Spdef(-/-); Apc(Min/+) mice developed approximately 3-fold more colon tumors than Spdef(+/+); Apc(Min/+) mice. Likewise, Spdef(-/-) mice developed approximately 3-fold more colon tumors than Spdef(+/+) mice after administration of AOM and DSS. After administration of 1,2-dimethylhydrazine and DSS, invasive carcinomas were observed exclusively in Spdef(-/-) mice. Conversely, expression of SPDEF was sufficient to promote cell-cycle exit in cells of established adenomas from Spdef(dox-intestine); Apc(Min/+) mice and in Spdef(dox-intestine) mice after administration of AOM + DSS. SPDEF inhibited the expression of β-catenin-target genes in mouse colon tumors, and interacted with β-catenin to block its transcriptional activity in CRC cell lines, resulting in lower levels of cyclin D1 and c-MYC.
Conclusions:
SPDEF is a colon tumor suppressor and a candidate therapeutic target for colon adenomas and adenocarcinoma.
Insights
Loss of SPDEF, a colon tumor suppressor, is frequent in colorectal cancers. SPDEF re-expression inhibits tumor growth by blocking beta-catenin signaling, suggesting it as a therapeutic target.
Area of Science:
- Oncology
- Gastroenterology
- Molecular Biology
Background:
- SPDEF (SAM pointed domain containing ETS transcription factor) is crucial for goblet and Paneth cell differentiation.
- SPDEF has demonstrated tumor-suppressive roles in breast, prostate, and colon cancers.
- This study investigates SPDEF levels in human colorectal tumors and its function in CRC models.
Purpose of the Study:
- To analyze SPDEF expression in human colorectal cancer (CRC) samples.
- To evaluate the tumor-suppressive functions of SPDEF in preclinical CRC models.
- To explore SPDEF as a potential therapeutic target for CRC.
Main Methods:
- Analyzed SPDEF mRNA and protein in over 500 human CRC samples and controls.
- Utilized Spdef knockout and wild-type mice in Apc(Min/+), AOM/DSS, and DMH/DSS models of CRC.
- Investigated SPDEF induction in established tumors and analyzed its effects on tumor characteristics and beta-catenin signaling in cell lines.
Main Results:
- SPDEF loss was observed in ~85% of human colorectal tumors, correlating with tumor progression.
- Spdef-deficient mice exhibited a ~3-fold increase in tumor development across multiple models.
- SPDEF re-expression suppressed tumor growth, promoted cell-cycle exit, and inhibited beta-catenin target genes like cyclin D1 and c-MYC.
Conclusions:
- SPDEF acts as a significant tumor suppressor in the colon.
- Loss of SPDEF is a hallmark of colorectal tumor progression.
- SPDEF represents a promising therapeutic target for colon adenomas and adenocarcinomas.
Related Concept Videos
02:23Abnormal Proliferation
01:12Loss of Tumor Suppressor Gene Functions
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
01:12Loss of Tumor Suppressor Gene Functions
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...
01:05Cancer-Critical Genes II: Tumor Suppressor Genes
When the function of certain critical genes, especially those involved in cell cycle regulation and cell growth signaling cascades, gets disrupted, it upsets the cell cycle progression. Such cells with unchecked cell cycles start proliferating uncontrollably and eventually develop into tumors.
Such genes that act...
01:12Role Of Notch Signalling In Intestinal Stem Cell Renewal
Direct cell-to-cell contact is needed for the activation of Notch signaling. The signal is initiated when a notch ligand binds to a receptor on an adjacent cell, also...
01:22Role of Ephrin-Eph Signalling in Intestinal Stem Cell Renewal