Currently, the cyclin-dependent kinase inhibitor p21 WAF-1 is considered to be a crucial downstream effector in the p53-specific pathway of negative growth control in mammalian cells. Wild-type p53, but not mutant forms of this protein, transactivate the WAF-1 gene. We show a correlation between growth-inhibition and induction of WAF-1 protein expression following transforming growth factor-beta 1 (TGF-beta 1) treatment of two human tumour cell lines devoid of wild-type p53 protein and in SV40-transformed WI38 fibroblasts. Inversely, TGF-beta 1 treatment of normal WI38 fibroblasts stimulates their growth and represses WAF-1 protein synthesis. As the mink lung epithelial CCL64 cell line is frequently used in TGF-B studies we included it in this study: TGF-beta 1 growth-inhibition is accompanied by induction of WAF-1 synthesis concomitantly with a reduction of cdk2 synthesis and of its histone kinase activity. However in the human tumour line RD, TGF-beta 1 did not affect cdk-2 protein levels but did reduce its histone kinase activity.

Download full-text PDF

Source
http://dx.doi.org/10.3892/ijo.7.2.337DOI Listing

Publication Analysis

Top Keywords

wild-type p53
8
induction waf-1
8
waf-1 protein
8
tgf-beta treatment
8
human tumour
8
wi38 fibroblasts
8
histone kinase
8
kinase activity
8
waf-1
5
protein
5

Similar Publications

DNA Damage-Induced Ferroptosis: A Boolean Model Regulating p53 and Non-Coding RNAs in Drug Resistance.

Proteomes

January 2025

Instituto de Matemática e Estatística, Departamento de Ciência da Computação, Universidade de São Paulo, Rua do Matão 1010, São Paulo 05508-090, SP, Brazil.

The tumor suppressor p53, in its wild-type form, plays a central role in cellular homeostasis by regulating senescence, apoptosis, and autophagy within the DNA damage response (DDR). Recent findings suggest that wild-type p53 also governs ferroptosis, an iron-dependent cell death process driven by lipid peroxidation. Post-translational modifications of p53 generate proteoforms that significantly enhance its functional diversity in regulating these mechanisms.

View Article and Find Full Text PDF

Extrapulmonary small cell neuroendocrine carcinoma (EP-SCNC) is a rare malignancy with a poor prognosis. Despite its morphological similarity to lung small cell carcinomas, its oncogenesis remains uncertain. One hundred and seventy-one EP-SCNC were enrolled in a multicenter study, and all tissue samples underwent an immunohistochemical p53 analysis.

View Article and Find Full Text PDF

The spatial role of M1 and M2 tumor-associated macrophages (M1/M2 TAMs) in precision medicine remains unclear. EGFR and TP53 are among the most frequently mutated genes in lung adenocarcinoma. We characterized the mutation status and density of M1/M2 TAMs within tumor islets and stroma in 117 lung adenocarcinomas using next-generation sequencing and immunohistochemistry, respectively.

View Article and Find Full Text PDF

Citrullination at the N-terminal region of MDM2 by the PADI4 enzyme.

Protein Sci

February 2025

Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza, Zaragoza, Spain.

PADI4 is one of the human isoforms of a family of enzymes involved in the conversion of arginine to citrulline. MDM2 is an E3 ubiquitin ligase that is critical for degradation of the tumor suppressor gene p53. We have previously shown that there is an interaction between MDM2 and PADI4 in cellulo, and that such interaction occurs through the N-terminal region of MDM2, N-MDM2, and in particular through residues Thr26, Val28, Phe91, and Lys98.

View Article and Find Full Text PDF

Low-grade endometrial stromal sarcoma (LG-ESS) can present diagnostic challenges, due to its overlapping morphological features with other uterine mesenchymal tumors. Misdiagnosis rates remain significant, and immunohistochemical data for LG-ESS are limited to small series and inconsistent antibody panels. This study aimed to refine the IHC profile of LG-ESS by analyzing a large, molecularly confirmed series of 147 cases using a panel of 24 antibodies, including newer markers like transgelin and smoothelin.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!