The Close Relationship between DNA Replication and the Selection of Differentiation Lineages of Human Erythroleukemia Cell Lines K562, HEL, and TF1 into Either Erythroid or Megakaryocytic Lineages

DNA replication is vital for an organism to proliferate and lying at the heart of this process is the enzyme DNA polymerase. Most DNA polymerases have a similar three dimensional fold, akin to a human right hand, despite differences in sequence homology. This structural homology would predict a relatively unvarying mechanism for DNA synthesis yet various polymerases exhibit markedly different properties on similar substrates, indicative of each type of polymerase being prescribed to a specific role in DNA replication. Several key conformational steps, discrete states, and structural moieties have been identified that contribute to the array of properties the polymerases exhibit. The ability of carcinogenic adducts to interfere with conformational processes by directly interacting with the protein explicates the mutagenic consequences these adducts impose. Recent studies have identified novel states that have been hypothesised to test the fit of the nascent base pair, and have also shown the enzyme to possess a lively quality by continually sampling various conformations. This review focuses on the homologous structural changes that take place in various DNA polymerases, both replicative and those involved in adduct bypass, the role these changes play in selection of a correct substrate, and how the presence of bulky carcinogenic adducts affects these changes.

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Effect of inhibitors of histone deacetylase on the induction of cell differentiation in murine and human erythroleukemia cell lines

Anti-Cancer Drugs ◽

10.1097/00001813-200507000-00008 ◽

2005 ◽

Vol 16 (6) ◽

pp. 635-643 ◽

Cited By ~ 8

Author(s):

Sybille Wittich ◽

Hans Scherf ◽

Changping Xie ◽

Birgit Heltweg ◽

Franck Dequiedt ◽

...

Keyword(s):

Cell Differentiation ◽

Histone Deacetylase ◽

Cell Lines ◽

Erythroleukemia Cell ◽

Effect Of Inhibitors

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Selection of Tobacco Cell Lines Resistant to Photobleaching Herbicides

Journal of Pesticide Science ◽

10.1584/jpestics.24.13 ◽

1999 ◽

Vol 24 (1) ◽

pp. 13-16 ◽

Cited By ~ 4

Author(s):

Mamoru HORIKOSHI ◽

Takashi HIROOKA

Keyword(s):

Cell Lines ◽

Tobacco Cell ◽

Selection Of

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Microarray gene expression profiling in colorectal (HCT116) and hepatocellular (HepG2) carcinoma cell lines treated withMelicope ptelefolialeaf extract reveals transcriptome profiles exhibiting anticancer activity

PeerJ ◽

10.7717/peerj.5203 ◽

2018 ◽

Vol 6 ◽

pp. e5203 ◽

Cited By ~ 6

Author(s):

Mohammad Faujul Kabir ◽

Johari Mohd Ali ◽

Onn Haji Hashim

Keyword(s):

Gene Expression ◽

Cell Cycle ◽

Dna Replication ◽

Cell Lines ◽

Microarray Data ◽

Expression Profiling ◽

Cell Cycle Progression ◽

Anticancer Activities ◽

Microarray Gene Expression ◽

Cycle Progression

BackgroundWe have previously reported anticancer activities ofMelicope ptelefolia(MP) leaf extracts on four different cancer cell lines. However, the underlying mechanisms of actions have yet to be deciphered. In the present study, the anticancer activity of MP hexane extract (MP-HX) on colorectal (HCT116) and hepatocellular carcinoma (HepG2) cell lines was characterized through microarray gene expression profiling.MethodsHCT116 and HepG2 cells were treated with MP-HX for 24 hr. Total RNA was extracted from the cells and used for transcriptome profiling using Applied Biosystem GeneChip™ Human Gene 2.0 ST Array. Gene expression data was analysed using an Applied Biosystems Expression Console and Transcriptome Analysis Console software. Pathway enrichment analyses was performed using Ingenuity Pathway Analysis (IPA) software. The microarray data was validated by profiling the expression of 17 genes through quantitative reverse transcription PCR (RT-qPCR).ResultsMP-HX induced differential expression of 1,290 and 1,325 genes in HCT116 and HepG2 cells, respectively (microarray data fold change, MA_FC ≥ ±2.0). The direction of gene expression change for the 17 genes assayed through RT-qPCR agree with the microarray data. In both cell lines, MP-HX modulated the expression of many genes in directions that support antiproliferative activity. IPA software analyses revealed MP-HX modulated canonical pathways, networks and biological processes that are associated with cell cycle, DNA replication, cellular growth and cell proliferation. In both cell lines, upregulation of genes which promote apoptosis, cell cycle arrest and growth inhibition were observed, while genes that are typically overexpressed in diverse human cancers or those that promoted cell cycle progression, DNA replication and cellular proliferation were downregulated. Some of the genes upregulated by MP-HX include pro-apoptotic genes (DDIT3, BBC3, JUN), cell cycle arresting (CDKN1A, CDKN2B), growth arrest/repair (TP53, GADD45A) and metastasis suppression (NDRG1). MP-HX downregulated the expression of genes that could promote anti-apoptotic effect, cell cycle progression, tumor development and progression, which include BIRC5, CCNA2, CCNB1, CCNB2, CCNE2, CDK1/2/6, GINS2, HELLS, MCM2/10 PLK1, RRM2 and SKP2. It is interesting to note that all six top-ranked genes proposed to be cancer-associated (PLK1, MCM2, MCM3, MCM7, MCM10 and SKP2) were downregulated by MP-HX in both cell lines.DiscussionThe present study showed that the anticancer activities of MP-HX are exerted through its actions on genes regulating apoptosis, cell proliferation, DNA replication and cell cycle progression. These findings further project the potential use of MP as a nutraceutical agent for cancer therapeutics.

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Pattern of pyruvate kinase isozymes in erythroleukemia cell lines and in normal human erythroblasts

Blood ◽

10.1182/blood.v64.4.930.bloodjournal644930 ◽

1984 ◽

Vol 64 (4) ◽

pp. 930-936 ◽

Cited By ~ 1

Author(s):

I Max-Audit ◽

U Testa ◽

D Kechemir ◽

M Titeux ◽

W Vainchenker ◽

...

Keyword(s):

Pyruvate Kinase ◽

Cell Lines ◽

Fetal Liver ◽

Erythroid Cells ◽

Low Concentrations ◽

Erythroleukemia Cell ◽

Erythroleukemic Cell ◽

High Level

To further investigate the erythroid nature of the two human erythroleukemia cell lines, K562 and HEL-60, and to define the ontogeny of pyruvate kinase (PK) isozymes (R, M2) in developing human erythroid cells, we have studied the isozymic alterations, if any, during differentiation of these cell lines in vitro and normoblasts isolated from fetal liver in vivo. PK activity of erythroleukemic cell lines was intermediate between that observed in leukocytes and in fetal liver erythroblasts. These cell lines contained a high level of M2-PK, but R- PK was always present, albeit at low concentrations, in all the clones or subclones we studied. Erythroblasts from fetal liver were separated according to density on a Stractan gradient. R-PK levels were nearly constant in the different fractions, whereas M2-PK levels markedly decreased as the erythroblasts became mature and almost completely disappeared in late erythroid cells. Thus, these results clearly demonstrate the erythroid origin of these cell lines.

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A human cancer cell line initiates DNA replication normally in the absence of ORC5 and ORC2 proteins

Journal of Biological Chemistry ◽

10.1074/jbc.ra120.015450 ◽

2020 ◽

Vol 295 (50) ◽

pp. 16949-16959

Author(s):

Etsuko Shibata ◽

Anindya Dutta

Keyword(s):

Dna Replication ◽

Cancer Cells ◽

Cell Lines ◽

Cancer Cell ◽

Origin Recognition Complex ◽

Human Cancer ◽

Cancer Cell Line ◽

Aaa Atpase ◽

Normal Number ◽

Mutant Cells

The origin recognition complex (ORC), composed of six subunits, ORC1–6, binds to origins of replication as a ring-shaped heterohexameric ATPase that is believed to be essential to recruit and load MCM2–7, the minichromosome maintenance protein complex, around DNA and initiate DNA replication. We previously reported the creation of viable cancer cell lines that lacked detectable ORC1 or ORC2 protein without a reduction in the number of origins firing. Here, using CRISPR-Cas9–mediated mutations, we report that human HCT116 colon cancer cells also survive when ORC5 protein expression is abolished via a mutation in the initiator ATG of the ORC5 gene. Even if an internal methionine is used to produce an undetectable, N terminally deleted ORC5, the protein would lack 80% of the AAA+ ATPase domain, including the Walker A motif. The ORC5-depleted cells show normal chromatin binding of MCM2–7 and initiate replication from a similar number of origins as WT cells. In addition, we introduced a second mutation in ORC2 in the ORC5 mutant cells, rendering both ORC5 and ORC2 proteins undetectable in the same cells and destabilizing the ORC1, ORC3, and ORC4 proteins. Yet the double mutant cells grow, recruit MCM2–7 normally to chromatin, and initiate DNA replication with normal number of origins. Thus, in these selected cancer cells, either a crippled ORC lacking ORC2 and ORC5 and present at minimal levels on the chromatin can recruit and load enough MCM2–7 to initiate DNA replication, or human cell lines can sometimes recruit MCM2–7 to origins independent of ORC.

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