Epigenetic alterations of Krüppel-like factor 4 and its tumor suppressor function in renal cell carcinoma

Heng Li1, Ji Wang, Wei Xiao

  • 1Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.

Carcinogenesis
|June 1, 2013
PubMed

Insights

Krüppel-like factor 4 (KLF4) is epigenetically silenced in renal cell cancers, acting as a tumor suppressor. Its reduced expression correlates with poor prognosis, suggesting KLF4 has prognostic value.

Area of Science:

  • Oncology
  • Molecular Biology
  • Epigenetics

Background:

  • Krüppel-like factor 4 (KLF4) has varied roles in malignancies.
  • The expression and function of KLF4 in renal cell carcinoma (RCC) are not well understood.

Purpose of the Study:

  • To investigate epigenetic alterations of KLF4 in RCC.
  • To determine the role of KLF4 in renal cell carcinoma progression.

Main Methods:

  • KLF4 expression analyzed via protein and mRNA in tumor vs. normal tissues.
  • Epigenetic alterations assessed using methylation-specific PCR and Sequenom MassARRAY.
  • Functional studies involved KLF4 overexpression in cell lines and in vivo models.

Main Results:

  • KLF4 expression was significantly decreased in various RCC types and linked to poorer patient survival.
  • Hypermethylation of the KLF4 promoter was identified as a key mechanism for its suppression.
  • Overexpression of KLF4 inhibited renal cancer cell growth, migration, invasion, tumorigenicity, and metastasis in vitro and in vivo.

Conclusions:

  • KLF4 functions as a tumor suppressor gene in renal cell carcinoma.
  • Epigenetic silencing via promoter CpG methylation contributes to KLF4 downregulation in RCC.
  • KLF4 holds prognostic significance for renal cell carcinoma progression.

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...
The Retinoblastoma Gene01:20

The Retinoblastoma Gene

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.
The first-ever tumor suppressor gene called Rb was identified in retinoblastoma - a rare eye tumor in children. In inherited forms of the disease, a child inherits one defective copy of the Rb gene, which predisposes them to retinoblastoma. However,...
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...
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...
Epigenetic Regulation01:37

Epigenetic Regulation

Epigenetic changes alter the physical structure of the DNA without changing the genetic sequence and often regulate whether genes are turned on or off. This regulation ensures that each cell produces only proteins necessary for its function. For example, proteins that promote bone growth are not produced in muscle cells. Epigenetic mechanisms play an essential role in healthy development. Conversely, precisely regulated epigenetic mechanisms are disrupted in diseases like cancer.
X-chromosome...
Epigenetic Regulation01:46

Epigenetic Regulation

Epigenetic mechanisms play an essential role in healthy development. Conversely, precisely regulated epigenetic mechanisms are disrupted in diseases like cancer.