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Steven J. Collins

Bio: Steven J. Collins is an academic researcher from United States Department of Veterans Affairs. The author has contributed to research in topics: Cell culture & Cellular differentiation. The author has an hindex of 6, co-authored 7 publications receiving 5266 citations.

Papers
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Journal ArticleDOI
24 Nov 1977-Nature
TL;DR: The derivation from myeloid leukaemic cells of a leukocyte culture is described here for the first time that by morphological and histochemical criteria clearly and persistently differentiates along the myeloids series without an exogenous source of conditioned medium.
Abstract: ATTEMPTS to develop long-term suspension cultures of human myeloid leukaemic cells have met with limited success. Lymphoblastoid lines carrying the Epstein–Barr virus genome occasionally arise during such attempts but these lymphoid cells originate from contaminating B lymphocytes and not from the leukaemic myeloid cells1. A line established from the pleural fluid of a patient with chronic myeloid leukaemia in blast crisis2 (designated K-562) has no B-cell or T-cell markers3–4 and does not seem to be of lymphoid origin4. Its lack of morphological and histochemical differentiation2–4, however, makes it difficult to determine whether these cells are derived from myeloblasts or more primitive stem cells4. Another less documented cell line (8261) derived from the peripheral blood of a patient with acute myelogenous leukaemia showed apparent morphological and functional differentiation in agar in the presence of a feeder layer of peripheral blood leukocytes but did not differentiate in suspension culture5. Our laboratory previously reported that cultures of differentiating myeloid leukaemic cells can be maintained for several months in suspension culture but only when enriched with conditioned media (CM) from certain monolayer fibroblastic cultures of first trimester whole human embryos (ref. 6 and Ruscetti et al. in preparation). We describe here for the first time the derivation from myeloid leukaemic cells of a leukocyte culture that by morphological and histochemical criteria clearly and persistently differentiates along the myeloid series without an exogenous source of conditioned medium.

2,115 citations

Journal ArticleDOI
TL;DR: The marked similarity in behavior of HL-60 cells and Friend cells in the presence of these inducing agents suggests that similar molecular mechanisms are involved in the induction of differentiation of these human myeloid and murine erythroid leukemic cells.
Abstract: A human leukemic cell line (designated HL-60) has recently been established from the peripheral blood leukocytes of a patient with acute promyelocytic leukemia. This cell line displays distinct morphological and histochemical commitment towards myeloid differentiation. The cultured cells are predominantly promyelocytes, but the addition of dimethyl sulfoxide to the culture induces them to differentiate into myelocytes, metamyelocytes, and banded and segmented neutrophils. All 150 clones developed from the HL-60 culture show similar morphological differentiation in the presence of dimethyl sulfoxide. Unlike the morphologically immature promyelocytes, the dimethyl sulfoxide-induced mature cells exhibit functional maturity as exemplified by phagocytic activity. A number of other compounds previously shown to induce erythroid differentiation of mouse erythroleukemia (Friend) cells can induce analogous maturation of the myeloid HL-60 cells. The marked similarity in behavior of HL-60 cells and Friend cells in the presence of these inducing agents suggests that similar molecular mechanisms are involved in the induction of differentiation of these human myeloid and murine erythroid leukemic cells.

1,556 citations

Journal ArticleDOI
01 Sep 1979-Blood
TL;DR: The HL-60 cultured cell line provides a continuous source of human cells for studying the molecular events of myeloid differentiation and the effects of physiologic, pharmacologic, and virologic elements on this process.

862 citations

Journal ArticleDOI
12 Aug 1982-Nature
TL;DR: It is demonstrated that sequences in normal human DNA homologous to the avian myc oncogene are present in multiple copies in the chromosomal DNA of the human leukaemia cell line HL-60, and this myc-related gene amplification is not present in other cultured human myeloid leukaems, including K-56214 and KG-115.
Abstract: Malignant transformation of cells by acute transforming RNA tumour viruses is mediated by the expression of certain specific pro viral DNA sequences (‘oncogenes’). These sequences have been well characterized and, in many cases, molecularly cloned1–8. These viral oncogenes are related to similar genes found in normal uninfected cells9,10. Moreover, these particular sequences are highly conserved in evolution4,11, suggesting that these genes have an important, albeit unknown, role in normal cell function. It has been suggested that an increased dosage of products of such endogenous oncogenes may be responsible for malignant transformation10,12,13. For example, increased expression of the endogenous chick c-myc oncogene has been observed in avian leukosis virus-induced transformation of chick bursal lymphocytes12. Here we demonstrate that sequences in normal human DNA homologous to the avian myc oncogene are present in multiple copies in the chromosomal DNA of the human leukaemia cell line HL-60. Other transformation-specific genes derived from the Abelson leukaemia virus4 and feline sarcoma virus6 are not amplified in HL-60. This myc-related gene amplification is not present in other cultured human myeloid leukaemia cells, including K-56214 and KG-115.

574 citations

Journal ArticleDOI
06 Jul 1984-Science
TL;DR: The levels of abl -related message were up to eight times higher in CML cell lines from patients at the blast crisis stage of the disease compared with CML cells obtained during the chronic phase and with non-CML cells.
Abstract: Expression of the cellular abl (c- abl ) oncogene was studied in K-562 and other chronic myelogenous leukemia (CML) cells and cell lines by means of Northern blot hybridization. In contrast to non-CML cells, which contained 7.4- and 6.8-kilobase abl -related transcripts, the CML cells contained a predominant and novel 8.2-kilobase abl -related RNA. In addition, the levels of abl -related message were up to eight times higher in CML cell lines from patients at the blast crisis stage of the disease compared with CML cells obtained during the chronic phase and with non-CML cells.

199 citations


Cited by
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Journal ArticleDOI
TL;DR: The number of these particle-associated proteins is consistent with the expected proteins of a retrovirus, but the sizes of some are distinct from those of most known retroviruses of the primate subgroups.
Abstract: Retrovirus particles with type C morphology were found in two T-cell lymphoblastoid cell lines, HUT 102 and CTCL-3, and in fresh peripheral blood lymphocytes obtained from a patient with a cutaneous T-cell lymphoma (mycosis fungoides). The cell lines continuously produce these viruses, which are collectively referred to as HTLV, strain CR(HTLVCR). Originally, the production of virus from HUT 102 cells required induction with 5-iodo-2′-deoxyuridine, but the cell line became a constitutive producer of virus at its 56th passage. Cell line CTCL-3 has been a constitutive producer of virus from its second passage in culture. Both mature and immature extracellular virus particles were seen in thin-section electron micrographs of fixed, pelleted cellular material; on occasion, typical type C budding virus particles were seen. No form of intracellular virus particle has been seen. Mature particles were 100-110 nm in diameter, consisted of an electron-dense core surrounded by an outer membrane separated by an electron-lucent region, banded at a density of 1.16 g/ml on a continuous 25-65% sucrose gradient, and contained 70S RNA and a DNA polymerase activity typical of viral reverse transcriptase (RT; RNA-dependent DNA nucleotidyltransferase). Under certain conditions of assay, HTLVCR RT showed cation preference for Mg2+ over Mn2+, distinct from the characteristics of cellular DNA polymerases purified from human lymphocytes and the RT from most type C viruses. Antibodies to cellular DNA polymerase γ and anti-bodies against RT purified from several animal retroviruses failed to detectably interact with HTLVCR RT under conditions that were positive for the respective homologous DNA polymerase, demonstrating a lack of close relationship of HTLVCR RT to cellular DNA polymerases γ or RT of these viruses. Six major proteins, with sizes of approximately 10,000, 13,000, 19,000, 24,000, 42,000, and 52,000 daltons, were apparent when doubly banded, disrupted HTLVCR particles were chromatographed on a NaDodSO4/polyacrylamide gel. The number of these particle-associated proteins is consistent with the expected proteins of a retrovirus, but the sizes of some are distinct from those of most known retroviruses of the primate subgroups.

4,728 citations

Journal ArticleDOI
04 Sep 1998-Science
TL;DR: The c-MYC oncogene is identified as a target gene in this signaling pathway and shown to be repressed by wild-type APC and activated by beta-catenin, and these effects were mediated through Tcf-4 binding sites in the c- MYC promoter.
Abstract: The adenomatous polyposis coli gene (APC) is a tumor suppressor gene that is inactivated in most colorectal cancers. Mutations of APC cause aberrant accumulation of beta-catenin, which then binds T cell factor-4 (Tcf-4), causing increased transcriptional activation of unknown genes. Here, the c-MYC oncogene is identified as a target gene in this signaling pathway. Expression of c-MYC was shown to be repressed by wild-type APC and activated by beta-catenin, and these effects were mediated through Tcf-4 binding sites in the c-MYC promoter. These results provide a molecular framework for understanding the previously enigmatic overexpression of c-MYC in colorectal cancers.

4,686 citations

Journal Article
TL;DR: Since the microculture tetrazolium assay provides sensitive and reproducible indices of growth as well as drug sensitivity in individual cell lines over the course of multiple passages and several months' cultivation, it appears suitable for initial-stage in vitro drug screening.
Abstract: For the past 30 years strategies for the preclinical discovery and development of potential anticancer agents have been based largely upon the testing of agents in mice bearing transplantable leukemias and solid tumors derived from a limited number of murine as well as human sources. The feasibility of implementing an alternate approach, namely combined in vitro/in vivo screening for selective cytotoxicity among panels of human tumor cell lines derived from a broad spectrum of human solid tumors is under investigation. A group of 30 cell lines acquired from a variety of sources and representing 8 lung cancer pathologies as well as 76 cell lines representing 10 other categories of human cancer (carcinomas of colon, breast, kidney, prostate, ovary, head and neck; glioma; leukemia; melanoma; and sarcoma) have exhibited acceptable growth characteristics and suitable colorimetric profiles in a single, standard culture medium. Measurements of in vitro growth in microculture wells by cell-mediated reduction of tetrazolium showed excellent correlation (0.89 less than r2 less than 0.98) with measurements of cellular protein in adherent cell line cultures as well as viable cell count in suspension cell line cultures (0.94 less than r2 less than 0.99). Since the microculture tetrazolium assay provides sensitive and reproducible indices of growth as well as drug sensitivity in individual cell lines over the course of multiple passages and several months' cultivation, it appears suitable for initial-stage in vitro drug screening.

3,098 citations

Journal ArticleDOI
08 Sep 1989-Science
TL;DR: Several transcribed sequences and conserved segments were identified in this cloned region and one corresponds to the cystic fibrosis gene and spans approximately 250,000 base pairs of genomic DNA.
Abstract: An understanding of the basic defect in the inherited disorder cystic fibrosis requires cloning of the cystic fibrosis gene and definition of its protein product. In the absence of direct functional information, chromosomal map position is a guide for locating the gene. Chromosome walking and jumping and complementary DNA hybridization were used to isolate DNA sequences, encompassing more than 500,000 base pairs, from the cystic fibrosis region on the long arm of human chromosome 7. Several transcribed sequences and conserved segments were identified in this cloned region. One of these corresponds to the cystic fibrosis gene and spans approximately 250,000 base pairs of genomic DNA.

3,050 citations

Journal ArticleDOI
04 Oct 1984-Nature
TL;DR: Transcription of the c-fos proto-oncogene is greatly increased within minutes of administering purified growth factors to quiescent 3T3 cells, and this stimulation is the most rapid transcriptional response to peptide growth factors yet described, implying a role for c- fos in cell-cycle control.
Abstract: Transcription of the c-fos proto-oncogene is greatly increased within minutes of administering purified growth factors to quiescent 3T3 cells. This stimulation is the most rapid transcriptional response to peptide growth factors yet described, and implies a role for c-fos in cell-cycle control. Transformation by c-fos may result from a temporal deregulation of this control.

2,762 citations