p53, also known as Tumor protein P53, cellular tumor antigen p53, or transformation-related protein 53 (TRP53) is a regulatory protein that is often mutated in human cancers. The p53 proteins are crucial in vertebrates, where they prevent cancer formation. As such, p53 has been described as "the guardian of the genome" because of its role in conserving stability by preventing genome mutation. Hence TP53 is classified as a tumor suppressor gene.
Marc Wallace Kirschner is an American cell biologist and biochemist and the founding chair of the Department of Systems Biology at Harvard Medical School. He is known for major discoveries in cell and developmental biology related to the dynamics and function of the cytoskeleton, the regulation of the cell cycle, and the process of signaling in embryos, as well as the evolution of the vertebrate body plan. He is a leader in applying mathematical approaches to biology. He is the John Franklin Enders University Professor at Harvard University. In 2021 he was elected to the American Philosophical Society.
ATM serine/threonine kinase or Ataxia-telangiectasia mutated, symbol ATM, is a serine/threonine protein kinase that is recruited and activated by DNA double-strand breaks, oxidative stress, topoisomerase cleavage complexes, splicing intermediates, R-loops and in some cases by single-strand DNA breaks. It phosphorylates several key proteins that initiate activation of the DNA damage checkpoint, leading to cell cycle arrest, DNA repair or apoptosis. Several of these targets, including p53, CHK2, BRCA1, NBS1 and H2AX are tumor suppressors.
Cell cycle checkpoints are control mechanisms in the eukaryotic cell cycle which ensure its proper progression. Each checkpoint serves as a potential termination point along the cell cycle, during which the conditions of the cell are assessed, with progression through the various phases of the cell cycle occurring only when favorable conditions are met. There are many checkpoints in the cell cycle, but the three major ones are: the G1 checkpoint, also known as the Start or restriction checkpoint or Major Checkpoint; the G2/M checkpoint; and the metaphase-to-anaphase transition, also known as the spindle checkpoint. Progression through these checkpoints is largely determined by the activation of cyclin-dependent kinases by regulatory protein subunits called cyclins, different forms of which are produced at each stage of the cell cycle to control the specific events that occur therein.
Mouse double minute 2 homolog (MDM2) also known as E3 ubiquitin-protein ligase Mdm2 is a protein that in humans is encoded by the MDM2 gene. Mdm2 is an important negative regulator of the p53 tumor suppressor. Mdm2 protein functions both as an E3 ubiquitin ligase that recognizes the N-terminal trans-activation domain (TAD) of the p53 tumor suppressor and as an inhibitor of p53 transcriptional activation.
p21Cip1, also known as cyclin-dependent kinase inhibitor 1 or CDK-interacting protein 1, is a cyclin-dependent kinase inhibitor (CKI) that is capable of inhibiting all cyclin/CDK complexes, though is primarily associated with inhibition of CDK2. p21 represents a major target of p53 activity and thus is associated with linking DNA damage to cell cycle arrest. This protein is encoded by the CDKN1A gene located on chromosome 6 (6p21.2) in humans.
p14ARF is an alternate reading frame protein product of the CDKN2A locus. p14ARF is induced in response to elevated mitogenic stimulation, such as aberrant growth signaling from MYC and Ras (protein). It accumulates mainly in the nucleolus where it forms stable complexes with NPM or Mdm2. These interactions allow p14ARF to act as a tumor suppressor by inhibiting ribosome biogenesis or initiating p53-dependent cell cycle arrest and apoptosis, respectively. p14ARF is an atypical protein, in terms of its transcription, its amino acid composition, and its degradation: it is transcribed in an alternate reading frame of a different protein, it is highly basic, and it is polyubiquinated at the N-terminus.
Karen Heather Vousden, CBE, FRS, FRSE, FMedSci is a British medical researcher. She is known for her work on the tumour suppressor protein, p53, and in particular her discovery of the important regulatory role of Mdm2, an attractive target for anti-cancer agents. From 2003 to 2016, she was the director of the Cancer Research UK Beatson Institute in Glasgow, UK, moving back to London in 2016 to take up the role of Chief Scientist at CRUK and Group Leader at the Francis Crick Institute.
Promyelocytic leukemia protein (PML) is the protein product of the PML gene. PML protein is a tumor suppressor protein required for the assembly of a number of nuclear structures, called PML-nuclear bodies, which form amongst the chromatin of the cell nucleus. These nuclear bodies are present in mammalian nuclei, at about 1 to 30 per cell nucleus. PML-NBs are known to have a number of regulatory cellular functions, including involvement in programmed cell death, genome stability, antiviral effects and controlling cell division. PML mutation or loss, and the subsequent dysregulation of these processes, has been implicated in a variety of cancers.
60S ribosomal protein L11 is a protein that in humans is encoded by the RPL11 gene.
F-box only protein 31 is a protein that in humans is encoded by the FBXO31 gene.
Nutlins are cis-imidazoline analogs which inhibit the interaction between mdm2 and tumor suppressor p53, and which were discovered by screening a chemical library by Vassilev et al. Nutlin-1, nutlin-2, and nutlin-3 were all identified in the same screen; however, Nutlin-3 is the compound most commonly used in anti-cancer studies. Nutlin small molecules occupy p53 binding pocket of MDM2 and effectively disrupt the p53–MDM2 interaction that leads to activation of the p53 pathway in p53 wild-type cells. Inhibiting the interaction between mdm2 and p53 stabilizes p53, and is thought to selectively induce a growth-inhibiting state called senescence in cancer cells. These compounds are therefore thought to work best on tumors that contain normal or "wild-type" p53. Nutlin-3 has been shown to affect the production of p53 within minutes.
Michael B. Elowitz is a biologist and professor of Biology, Bioengineering, and Applied Physics at the California Institute of Technology, and investigator at the Howard Hughes Medical Institute. In 2007 he was the recipient of the Genius grant, better known as the MacArthur Fellows Program for the design of a synthetic gene regulatory network, the Repressilator, which helped initiate the field of synthetic biology. He was the first to show how inherently random effects, or 'noise', in gene expression could be detected and quantified in living cells, leading to a growing recognition of the many roles that noise plays in living cells. His work in Synthetic Biology and Noise represent two foundations of the field of Systems Biology. Since then, his laboratory has contributed to the development of synthetic biological circuits that perform a range of functions inside cells, and revealed biological circuit design principles underlying epigenetic memory, cell fate control, cell-cell communication, and multicellular behaviors.
In molecular biology mir-605 microRNA is a short RNA molecule. MicroRNAs function to regulate the expression levels of other genes by several mechanisms.
DNA damage is an alteration in the chemical structure of DNA, such as a break in a strand of DNA, a nucleobase missing from the backbone of DNA, or a chemically changed base such as 8-OHdG. DNA damage can occur naturally or via environmental factors, but is distinctly different from mutation, although both are types of error in DNA. DNA damage is an abnormal chemical structure in DNA, while a mutation is a change in the sequence of base pairs. DNA damages cause changes in the structure of the genetic material and prevents the replication mechanism from functioning and performing properly. The DNA damage response (DDR) is a complex signal transduction pathway which recognizes when DNA is damaged and initiates the cellular response to the damage.
Ruth Lehmann is a developmental and cell biologist. She is the Director of the Whitehead Institute for Biomedical Research. She previously was affiliated with the New York University School of Medicine, where she was the Director of the Skirball Institute of Biomolecular Medicine, the Laura and Isaac Perlmutter Professor of Cell Biology, and the Chair of the Department of Cell Biology. Her research focuses on germ cells and embryogenesis.
In systems biology, live single-cell imaging is a live-cell imaging technique that combines traditional live-cell imaging and time-lapse microscopy techniques with automated cell tracking and feature extraction, drawing many techniques from high-content screening. It is used to study signalling dynamics and behaviour in populations of individual living cells. Live single-cell studies can reveal key behaviours that would otherwise be masked in population averaging experiments such as western blots.
Shaomeng Wang is a Chinese-American chemist currently the Warner-Lambert/Parke-Davis Professor in Medicine at University of Michigan and a former Co-Editor-in-Chief at American Chemical Society's Journal of Medicinal Chemistry. A cited expert in his field, his interests are synthesis and design of moleculars, neurological diseases and computational and informatics. He was Elected as Fellow at the National Academy of Inventors in 2014. Dr. Wang was named to the AAAS Fellows Section on Pharmaceutical Sciences in 2019, and is the recipient of the Division of Medicinal Chemistry Award 2020 American Chemical Society.
Xin Lu is a Professor of Cancer Biology and Director of the Ludwig Institute for Cancer Research at the University of Oxford. She is known for her discovery of and research on the ASPP family of proteins.
Guillermina 'Gigi' Lozano is an American geneticist. She is a Professor and Hubert L. Olive Stringer Distinguished Chair in Oncology in Honor of Sue Gribble Stringer at the University of Texas MD Anderson Cancer Center, Houston, Texas. Lozano is recognised for her studies of the p53 tumour suppressor pathway, characterising the protein as a regulator of gene expression and that is disturbed in many cancers. She was the first to recognize that the p53 gene encoded a transcriptional activator of other genes Her lab has made significant contributions by developing and analyzing mouse models to study the activities of mutant p53, revealing how these mutations drive tumor development and progression. She also found out how the Mdm2 and Mdm4 proteins work in the body, especially in stopping cancer and controlling p53. This research suggested that blocking Mdm2/4 could be a new way to treat cancer.
