Related Experiment Video

Updated: Jun 2, 2026

Discovery of Driver Genes in Colorectal HT29-derived Cancer Stem-Like Tumorspheres
06:52

Discovery of Driver Genes in Colorectal HT29-derived Cancer Stem-Like Tumorspheres

Published on: July 22, 2020

PNAS-4 expression and its relationship to p53 in colorectal cancer

Bin Zhou1, Hui Yan, Yuan Li

  • 1Laboratory of Digestive Surgery, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, Sichuan Province, China.

Molecular Biology Reports
|May 11, 2011
PubMed

Insights

PNAS-4 is a novel pro-apoptotic protein. This study found PNAS-4 is not a p53 target gene, but its overexpression correlates with p53 inactivity in colorectal cancer, impacting tumor progression.

Area of Science:

  • Molecular Biology
  • Cancer Research
  • Genetics

Background:

  • PNAS-4 is a novel pro-apoptotic protein involved in DNA damage response.
  • Mechanisms regulating PNAS-4 expression in tumors are not well understood.
  • The study investigated the relationship between PNAS-4 and p53 in colorectal cancer.

Purpose of the Study:

  • To determine if PNAS-4 is a downstream target of p53.
  • To investigate the correlation between PNAS-4 expression and p53 mutation status in colorectal cancer.
  • To explore the role of PNAS-4 in colorectal cancer progression and metastasis.

Main Methods:

  • Searched for p53-binding sites in the PNAS-4 gene.
  • Used real-time PCR to analyze PNAS-4 and known p53 target gene expression in p53-silenced HCT116 cells.
  • Examined PNAS-4 expression and p53 mutation status in colorectal cancer patient samples.

Main Results:

  • No p53-binding sites were found in the PNAS-4 gene.
  • PNAS-4 was upregulated, while known p53 targets were downregulated, after p53 silencing.
  • PNAS-4 was upregulated in colorectal cancers compared to normal tissues and correlated with p53 mutant status.
  • PNAS-4 overexpression was associated with lymph node metastasis.

Conclusions:

  • PNAS-4 is not a p53 target gene.
  • PNAS-4 overexpression is linked to p53 inactivity in colorectal cancer.
  • PNAS-4 may play a role in colorectal cancer progression and metastasis.

More Related Videos

Deficient Pms2, ERCC1, Ku86, CcOI in Field Defects During Progression to Colon Cancer28:15

Deficient Pms2, ERCC1, Ku86, CcOI in Field Defects During Progression to Colon Cancer

Published on: July 28, 2010

In vitro Organoid Culture of Primary Mouse Colon Tumors07:33

In vitro Organoid Culture of Primary Mouse Colon Tumors

Published on: May 17, 2013

Related Concept Videos

Abnormal Proliferation02:23

Abnormal Proliferation

Under normal conditions, most adult cells remain in a non-proliferative state unless stimulated by internal or external factors to replace lost cells. Abnormal cell proliferation is a condition in which the cell's growth exceeds and is uncoordinated with normal cells. In such situations, cell division persists in the same excessive manner even after cessation of the stimuli, leading to persistent tumors. The tumor arises from the damaged cells that replicate to pass the damage to the daughter...
Interactions Between Signaling Pathways01:19

Interactions Between Signaling Pathways

Signaling cascades usually lack linearity. Multiple pathways interact and regulate one another, allowing cells to integrate and respond to diverse environmental stimuli.
Convergence and divergence, and cross-talk between signaling pathways
Two distinct signaling pathways can converge on a single functional unit, which may either be a single protein or a complex of proteins. The response is either functionally distinct or synergistic between the two pathways but different from the response...
Tumor Progression02:07

Tumor Progression

Tumor progression is a phenomenon where the pre-formed tumor acquires successive mutations to become clinically more aggressive and malignant. In the 1950s, Foulds first described the stepwise progression of cancer cells through successive stages.
Colon cancer is one of the best-documented examples of tumor progression. Early mutation in the APC gene in colon cells causes a small growth on the colon wall called a polyp. With time, this polyp grows into a benign, pre-cancerous tumor. Further...
Loss of Tumor Suppressor Gene Functions01:12

Loss of Tumor Suppressor Gene Functions

Tumor suppressor genes are normal genes that can slow down cell division, repair DNA mistakes, or program the cells for apoptosis in case of irreparable damage. Hence, they play an essential role in preventing the proliferation of damaged cells.
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...
mTOR Signaling and Cancer Progression03:03

mTOR Signaling and Cancer Progression

The mammalian target of rapamycin or mTOR protein was discovered in 1994 due to its direct interaction with rapamycin. The protein gets its name from a yeast homolog called TOR. The mTOR protein complex in mammalian cells plays a major role in balancing anabolic processes such as the synthesis of proteins, lipids, and nucleotides and catabolic processes, such as autophagy in response to environmental cues, such as availability of nutrients and growth factors.
The mTOR pathway or the...