# Functional role of STRAP in colorectal cancer metastasis and in chemoresistance

> **NIH VA I01** · BIRMINGHAM VA MEDICAL CENTER · 2020 · —

## Abstract

Project Summary/Abstract
 Despite the high rate of recurrence following therapy in colorectal cancer (CRC) and relatively rapid
pace of cancer stem-like cell research in solid tumors, researches are impeded due to limited knowledge of the
CRC epithelial stem cell hierarchy and complex heterogeneity of the disease. Recent evidences suggest that
colorectal tumors comprise a small fraction of cancer stem-like cells that seed the tumor bulk and may be
responsible for metastasis, resistance to therapy, and tumor recurrence. Others (Buess et al., 2004) and we
(Halder et al, 2006) have shown that STRAP (Serine Threonine Kinase Receptor Associated Protein) is
significantly upregulated in colorectal carcinomas including metastases, and upregulation of STRAP in CRC
patients contributes to worse survival with chemotherapy, suggesting its potential contribution to the
aggressive disease and chemoresistance. Therefore, understanding the functional role of STRAP in CRC
metastasis, in the maintenance of cancer stem-like cells, and in chemoresistance is very crucial.
 We identified the novel WD-domain containing protein called STRAP that binds with both TGF-ß
receptor complex and Smad7, and inhibits TGF-ß signaling. We have shown that STRAP is upregulated in
several cancers, induces epithelial-to-mesenchymal (EMT) transition (Kashikar et al, 2010), and promotes cell
growth and tumorigenicity in vitro in a TGF-ß-independent manner (Halder et al, 2006). Our preliminary data
suggest that STRAP regulates the expression of MMPs, and Wnt/ß-catenin and Notch signaling. To determine
the role of STRAP in vivo, we have recently generated Strap knock out mice, which is embryonic lethal at 9.5
dpc. Azoxymethane treatment of the Strap heterozygous mice produces fewer and smaller tumors when
compared with wild type mice. To study the effect of STRAP in an organ specific manner, we have also
generated conditional knock out mice using the Cre-lox approach. Therefore, little is known about the TGF-ß-
independent role of STRAP in intestinal cancer metastasis and chemoresistance. Based on the background
information and our preliminary results, we have formulated the following hypotheses: Upregulation of STRAP
in colorectal cancer plays an active role in metastasis and its functional interaction with Wnt/ß-catenin and
Notch pathway is involved in colon cancer stem-like cell self-renewal and chemoresistance. The following
Specific Aims are proposed to test these hypotheses: Aim 1: Determine the mechanism of how STRAP
contributes to colorectal cancer metastasis. Aim 2: Determine the role of STRAP in the maintenance and self-
renewal of colon cancer stem-like cells. Aim 3: Determine the role of STRAP in regulating chemoresistance of
colorectal cancer.
 Impact: Despite the development of treatment regimens, metastasis remains the most critical
determinant of survival, as median survival for patients with metastatic colorectal cancer is 5 months among
veterans. Moreover, drug resistance...

## Key facts

- **NIH application ID:** 9864006
- **Project number:** 5I01BX003497-04
- **Recipient organization:** BIRMINGHAM VA MEDICAL CENTER
- **Principal Investigator:** PRAN K DATTA
- **Activity code:** I01 (R01, R21, SBIR, etc.)
- **Funding institute:** VA
- **Fiscal year:** 2020
- **Award amount:** —
- **Award type:** 5
- **Project period:** 2017-01-01 → 2020-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9864006

## Citation

> US National Institutes of Health, RePORTER application 9864006, Functional role of STRAP in colorectal cancer metastasis and in chemoresistance (5I01BX003497-04). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/9864006. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*
