Phospho-ΔNp63α-dependent regulation of autophagic signaling through transcription and micro-RNA modulation.

Abstract

Cisplatin was shown to induce the ataxia telangiectasia mutated (ATM)-dependent phosphorylation of tumor protein p63 isoform, (ΔNp63α), leading to a transcriptional regulation of specific genes implicated in the control of cell death of squamous cell carcinoma (SCC) cells. We previously observed that the cisplatin-induced phosphorylated (p)-ΔNp63α transcriptionally regulates the expression of specific microRNAs (miRNAs) in SCC cells. We found here that cisplatin exposure of SCC cells led to modulation of the members of the autophagic pathway, such as Atg1/Ulk1, Atg3, Atg4A, Atg5, Atg6/Becn1, Atg7, Atg9A and Atg10, by a direct p-ΔNp63α-dependent transcriptional regulation. We further found that specific miRNAs (miR-181a, miR-519a, miR-374a and miR-630), which are critical downstream targets of the p-ΔNp63α, modulated the protein levels of ATG5, ATG6/BECN1, ATG10, ATG12, ATG16L1 and UVRAG, adding another level of expression control for autophagic pathways in SCC cells upon cisplatin exposure. Our data support the notion that the cisplatin-induced p-ΔNp63α could regulate key pathways implicated in response of cancer cells to chemotherapeutics.

• Authors: Yiping Huang, Rafael Guerrero-Preston, Edward A Ratovitski
• Journal: Cell cycle (Georgetown, Tex.) (Cell Cycle) Vol. 11 Issue 6 Pg. 1247-59 (Mar 15 2012) ISSN: 1551-4005 [Electronic] United States
• PMID: 22356768 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• ATG5 protein, human
• Autophagy-Related Protein 5
• Cell Cycle Proteins
• Culture Media
• MicroRNAs
• Microtubule-Associated Proteins
• Phosphoproteins
• Protein Isoforms
• TP53 protein, human
• TP63 protein, human
• Trans-Activators
• Transcription Factors
• Tumor Suppressor Protein p53
• Tumor Suppressor Proteins
• UVRAG protein, human
• Cisplatin

Topics

• Autophagy
• Autophagy-Related Protein 5
• Carcinoma, Squamous Cell (metabolism, pathology)
• Cell Cycle Checkpoints
• Cell Cycle Proteins (genetics, metabolism)
• Cell Line, Tumor
• Cell Survival
• Chromatin Immunoprecipitation
• Cisplatin (pharmacology)
• Culture Media (metabolism)
• Gene Expression Regulation, Neoplastic
• Humans
• MicroRNAs (genetics, metabolism)
• Microtubule-Associated Proteins (genetics, metabolism)
• Phosphoproteins (genetics, metabolism)
• Protein Isoforms (genetics, metabolism)
• RNA Processing, Post-Transcriptional
• Signal Transduction
• Trans-Activators (genetics, metabolism)
• Transcription Factors (genetics, metabolism)
• Transcription, Genetic
• Tumor Suppressor Protein p53 (genetics, metabolism)
• Tumor Suppressor Proteins (genetics, metabolism)