Related Experiment Video
Updated: Sep 18, 2025

Development and Maintenance of a Preclinical Patient Derived Tumor Xenograft Model for the Investigation of Novel Anti-Cancer Therapies
Published on: September 30, 2016
Effects of PIK3CA Gene Modifications on Radiosensitivity in Colorectal Cancer Cells
Ghazi Alsbeih1, Khaled Al-Hadyan1
1Radiation Biology Section, Biomedical Physics Department, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia.
Abstract:
The phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) plays a critical role in cell growth and survival. PIK3CA somatic mutations are linked to the PIK3CA-related overgrowth spectrum (PROS) syndrome. Cells from those patients appeared to be associated with a moderate but significant radiosensitivity. Mutations or amplifications in this gene are common in breast, colorectal, and lung cancers. Alterations in the PIK3CA gene, including amplification and mutation, are common in cancer, but their influence on radiotherapy is not yet fully understood. This report reveals a potential association between PIK3CA gene modifications and radiosensitivity (p < 0.05) deducted from 8 established colorectal cancer cell lines (HT-29, DLD-1, HCT-116, SW480, HCT-15, Colo-320, and LoVo). Meanwhile gene amplification (> 2) seems to be linked to increased radiation sensitivity, mutations appear to be associated with increased radioresistance in colorectal cancer cells. Leveraging this relationship, PIK3CA amplification and mutations could act as biomarker to pinpoint patients who might benefit from more personalized radiotherapy regimens. However, this association is preliminary and hypothesis-generating in view of the limited number of cases. Further studies are needed to confirm this conclusion. By uncovering the distinct mechanistic effects of these PIK3CA alterations on radiosensitivity phenotype in both normal and cancerous cells, researchers can lay the groundwork for tailored radiotherapy strategies in colorectal cancer. This insight could enhance treatment effectiveness while reducing side effects, ultimately leading to improved patient outcomes.
Insights
Alterations in the PIK3CA gene impact radiosensitivity in colorectal cancer. PIK3CA amplification may increase radiation sensitivity, while mutations suggest radioresistance, guiding personalized radiotherapy.
Area of Science:
- Oncology
- Molecular Biology
- Radiotherapy Research
Background:
- The phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) is crucial for cell growth and survival.
- PIK3CA mutations are implicated in the PIK3CA-related overgrowth spectrum (PROS) and various cancers, including colorectal cancer.
- The precise impact of PIK3CA alterations on radiotherapy response remains largely unelucidated.
Purpose of the Study:
- To investigate the association between PIK3CA gene modifications (amplification and mutation) and radiosensitivity in colorectal cancer cell lines.
- To explore the potential of PIK3CA alterations as predictive biomarkers for radiotherapy response.
Main Methods:
- Analysis of 8 established colorectal cancer cell lines (HT-29, DLD-1, HCT-116, SW480, HCT-15, Colo-320, and LoVo).
- Assessment of PIK3CA gene amplification and mutation status.
- Correlation of genetic alterations with observed radiosensitivity phenotypes.
Main Results:
- A statistically significant association (p < 0.05) was found between PIK3CA modifications and radiosensitivity in colorectal cancer cells.
- PIK3CA gene amplification (> 2) correlated with increased sensitivity to radiation.
- PIK3CA mutations were associated with increased radioresistance in colorectal cancer cells.
Conclusions:
- PIK3CA gene alterations exhibit distinct effects on radiosensitivity in colorectal cancer.
- PIK3CA amplification and mutations may serve as potential biomarkers for personalized radiotherapy selection.
- Further research is warranted to validate these preliminary findings and elucidate the underlying mechanisms for tailored cancer treatment.
Related Concept Videos
PI3K/mTOR/AKT Signaling Pathway
Abnormal Proliferation
mTOR Signaling and Cancer Progression
The mTOR pathway or the...
Cancer-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...
The Ras Gene
Ras is a...
Cancer-Critical Genes I: Proto-oncogenes
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...

