Project description:Genomic instability is one of the hallmarks of cancer. Several chemotherapeutic drugs and radiotherapy induce DNA damage to prevent cancer cell replication. Cells in turn activate different DNA damage response (DDR) pathways to either repair the damage or induce cell death. These DDR pathways also elicit metabolic alterations which can play a significant role in the proper functioning of the cells. The understanding of these metabolic effects resulting from different types of DNA damage and repair mechanisms is currently lacking. In this study, we used NMR metabolomics to identify metabolic pathways which are altered in response to different DNA damaging agents. By comparing the metabolic responses in MCF-7 cells, we identified the activation of poly (ADP-ribose) polymerase (PARP) in methyl methanesulfonate (MMS)-induced DNA damage. PARP activation led to a significant depletion of NAD+. PARP inhibition using veliparib (ABT-888) was able to successfully restore the NAD+ levels in MMS-treated cells. In addition, double strand break induction by MMS and veliparib exhibited similar metabolic responses as zeocin, suggesting an application of metabolomics to classify the types of DNA damage responses. This prediction was validated by studying the metabolic responses elicited by radiation. Our findings indicate that cancer cell metabolic responses depend on the type of DNA damage responses and can also be used to classify the type of DNA damage.
Project description:Type I, II, III and V collagens were commonly identified in human, pig, and mouse breast ECM. Mammary epithelial cells were able to form acini on certain types or combinations of the four collagens at normal breast tissue stiffness levels. Comparison of the collagen species in mouse normal breast and breast tumor ECM revealed common and distinct sets of collagens within the two types of tissues. Elevated collagen type I alpha 1 chain expression was found in human breast cancers. Collagen type XXV alpha 1 chain was identified in mouse breast tumors but not in normal breast tissues. Our data provide insights into modeling human breast pathophysiological structures and functions using native tissue-derived hydrogels and potential contributions of different collagen types or their monomers in breast cancer development.
Project description:Type I, II, III and V collagens were commonly identified in human, pig, and mouse breast ECM. Mammary epithelial cells were able to form acini on certain types or combinations of the four collagens at normal breast tissue stiffness levels. Comparison of the collagen species in mouse normal breast and breast tumor ECM revealed common and distinct sets of collagens within the two types of tissues. Elevated collagen type I alpha 1 chain expression was found in human breast cancers. Collagen type XXV alpha 1 chain was identified in mouse breast tumors but not in normal breast tissues. Our data provide insights into modeling human breast pathophysiological structures and functions using native tissue-derived hydrogels and potential contributions of different collagen types or their monomers in breast cancer development.
Project description:We performed whole-genome methylation analysis using 450K Illumina BeadArrays on different human cell types. In total 24 experiments were performed. Dermal fibroblasts, three different epidermal melanocytes (dark, medium and light pigmentation), epidermal keratinocytes, mammary fibroblasts, mammary epithelial cells, mammary endothelial cells and mesenchymal stem cells were analyzed in technical duplicates. Unmethylated DNA were analyzed in technical duplicates. Two different normal breast tissue samples were analyzed. Finally peripheral blood leukocytes and an enzymatically methylated sample were analyzed. Genome-wide DNA methylation analysis of different cell types using Illumina Human Methylation 450K Beadchips.
Project description:We are investigating the transcriptional response of yeast to treatment with enediynes or gamma radiation, which generate different extents of double or single strand breaks in DNA. We used microarrays to detail the global programme of gene expression underlying the DNA damage response in yeast Keywords: dose
Project description:We are investigating the transcriptional response of yeast to modulation of the expression of base excision repair players, these generate different dna lesions of abasic sites of strand breaks; We used microarrays to detail the global programme of gene expression underlying the DNA damage response in yeast Experiment Overall Design: Yeaststrains with different expression levels of players in base excision repair (in biological triplicate) were grown to mid log phase. The expression responses were compared to each other and we have deciphered a gene expression profile that is specific for DNA damage in yeast.
Project description:We are investigating the transcriptional response of yeast to modulation of the expression of base excision repair players, these generate different dna lesions of abasic sites of strand breaks We used microarrays to detail the global programme of gene expression underlying the DNA damage response in yeast Keywords: dose
Project description:Heldt2018 - Proliferation-quiescence decision
in response to DNA damage
This model is described in the article:
A comprehensive model for
the proliferation-quiescence decision in response to endogenous
DNA damage in human cells.
Heldt FS, Barr AR, Cooper S, Bakal
C, Novák B.
Proc. Natl. Acad. Sci. U.S.A. 2018 Feb;
:
Abstract:
Human cells that suffer mild DNA damage can enter a
reversible state of growth arrest known as quiescence. This
decision to temporarily exit the cell cycle is essential to
prevent the propagation of mutations, and most cancer cells
harbor defects in the underlying control system. Here we
present a mechanistic mathematical model to study the
proliferation-quiescence decision in nontransformed human
cells. We show that two bistable switches, the restriction
point (RP) and the G1/S transition, mediate this decision by
integrating DNA damage and mitogen signals. In particular, our
data suggest that the cyclin-dependent kinase inhibitor p21
(Cip1/Waf1), which is expressed in response to DNA damage,
promotes quiescence by blocking positive feedback loops that
facilitate G1 progression downstream of serum stimulation.
Intriguingly, cells exploit bistability in the RP to convert
graded p21 and mitogen signals into an all-or-nothing
cell-cycle response. The same mechanism creates a window of
opportunity where G1 cells that have passed the RP can revert
to quiescence if exposed to DNA damage. We present experimental
evidence that cells gradually lose this ability to revert to
quiescence as they progress through G1 and that the onset of
rapid p21 degradation at the G1/S transition prevents this
response altogether, insulating S phase from mild, endogenous
DNA damage. Thus, two bistable switches conspire in the early
cell cycle to provide both sensitivity and robustness to
external stimuli.
This model is hosted on
BioModels Database
and identified by:
MODEL1703030000.
To cite BioModels Database, please use:
Chelliah V et al. BioModels: ten-year
anniversary. Nucl. Acids Res. 2015, 43(Database
issue):D542-8.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
Project description:An in silico model to examine damage-induced circadian phase shifts by investigating a possible mechanism linking circadian rhythms to metabolism. The proposed model involves two DNA damage response proteins, SIRT1 and PARP1, that are each consumers of nicotinamide adenine dinucleotide (NAD), a metabolite involved in oxidation-reduction reactions and in ATP synthesis.