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Updated: Aug 13, 2026

The Use of Reverse Phase Protein Arrays (RPPA) to Explore Protein Expression Variation within Individual Renal Cell Cancers
12:22

The Use of Reverse Phase Protein Arrays (RPPA) to Explore Protein Expression Variation within Individual Renal Cell Cancers

Published on: January 22, 2013

Expression and sequence analysis of the p21(WAF1/CIP1) gene in renal cancers

C N Papandreou1, T Bogenrieder, F Loganzo

  • 1Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.

Urology
|March 1, 1997
PubMed
Abstract

Insights

Mutations in the p21 gene are rare in renal cancers. Aberrant regulation of p21 protein expression may contribute to renal cancer cell growth.

Area of Science:

  • Oncology
  • Molecular Biology
  • Cell Cycle Regulation

Background:

  • The p21(WAF1/CIP1) protein is a cyclin-dependent kinase inhibitor crucial for cell cycle arrest.
  • It functions as a downstream effector in the p53 pathway, regulating cell growth.
  • Understanding p21 alterations is vital for comprehending renal cancer development.

Purpose of the Study:

  • To investigate mutations and alterations in p21 expression in renal cancer cell lines.
  • To determine if these genetic changes contribute to uncontrolled renal cancer cell proliferation.

Main Methods:

  • Analysis of the p21 gene coding region for mutations using single-stranded conformation polymorphism and DNA sequencing.
  • Assessment of p21 gene expression at both mRNA (Northern analysis) and protein (Western analysis) levels in 12 renal cancer cell lines.

Main Results:

  • Mutations in the p21 gene were detected in two cell lines, but these did not alter the amino acid sequence.
  • p21 mRNA was detected in 8 of 12 cell lines, while p21 protein was found in 9 of 12.
  • Significant variation in p21 protein levels was observed across the studied renal cancer cell lines.

Conclusions:

  • Mutation of the p21 gene is uncommon in renal cancer cell lines and unlikely to be the primary cause of uncontrolled growth.
  • Aberrant regulation of p21 protein expression, rather than mutation, may play a significant role in the pathogenesis of renal cancer.

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