A transforming activity not detected by DNA transfer to NIH 3T3 cells is detected by JB6 mouse epidermal cells.

Transfection of four different mouse epidermal tumor cell DNAs into NIH 3T3 cells yielded neither morphologically altered foci nor anchorage independence. However, promotion-sensitive, but not promotion-insensitive, JB6 mouse epidermal cell lines were permissive for the expression of anchorage independence after transfection of DNA from three of these tumor cell lines. This transforming activity and the promotion-sensitive activity that confers sensitivity to promotion of transformation show differences in restriction enzyme sensitivity. In view of this difference and the differences in both recipient cells and 12-O-tetradecanoyl-phorbol-13-acetate dependence of expression, it appears that the transforming activity and the promotion-sensitive activity are specified by different genes. The JB6 promotion-sensitive cell lines may be useful for detecting and cloning transforming genes that escape detection in the NIH 3T3 cell focus assay.

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Effects of ouabain on NIH/3T3 cells transformed with retrovirai oncogenes and on human tumor cell lines

International Journal of Cancer ◽

10.1002/ijc.2910400514 ◽

1987 ◽

Vol 40 (5) ◽

pp. 653-658 ◽

Cited By ~ 6

Author(s):

Pierosandro Tagliaferri ◽

Kazuyoshi Yanagihara ◽

Fortunate Ciardiello ◽

Neil Talbot ◽

Ursula Flatow ◽

...

Keyword(s):

Tumor Cell ◽

Cell Lines ◽

Human Tumor ◽

Tumor Cell Lines ◽

3T3 Cells ◽

Human Tumor Cell ◽

Human Tumor Cell Lines ◽

Nih 3T3 ◽

Nih 3T3 Cells

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Constitutive phosphorylation of eps8 in tumor cell lines: relevance to malignant transformation.

Molecular and Cellular Biology ◽

10.1128/mcb.15.7.3805 ◽

1995 ◽

Vol 15 (7) ◽

pp. 3805-3812 ◽

Cited By ~ 46

Author(s):

B Matoskova ◽

W T Wong ◽

A E Salcini ◽

P G Pelicci ◽

P P Di Fiore

Keyword(s):

Tumor Cell ◽

Tyrosine Phosphorylation ◽

Cell Lines ◽

Egf Receptor ◽

Human Tumor ◽

Tumor Cell Lines ◽

3T3 Cells ◽

Nih 3T3 ◽

Nih 3T3 Cells

eps8, a recently identified tyrosine kinase substrate, has been shown to augment epidermal growth factor (EGF) responsiveness, implicating it in EGF receptor (EGFR)-mediated mitogenic signaling. We investigated the status of eps8 phosphorylation in normal and transformed cells and the role of eps8 in transformation. In NIH 3T3 cells overexpressing EGFR (NIH-EGFR), eps8 becomes rapidly phosphorylated upon EGF stimulation. At receptor-saturating doses of EGF, approximately 30% of the eps8 pool is tyrosine phosphorylated. Under physiological conditions of activation (i.e., at low receptor occupancy), corresponding to the 50% effective dose of EGF for mitogenesis, approximately 3 to 4% of the eps8 contains phosphotyrosine. In human tumor cell lines, we detected constitutive tyrosine phosphorylation of eps8, with a stoichiometry (approximately 5%) similar to that associated with potent mitogenic response in NIH-EGFR cells. Overexpression of eps8 was able to transform NIH 3T3 cells under limiting conditions of activation of the EGFR pathway. Concomitant tyrosine phosphorylation of eps8 and shc, but not of rasGAP, phospholipase C-gamma, and eps15, was frequently detected in tumor cells. This suggested that eps8 and shc might be part of a pathway which is preferentially selected in some tumors. Cooperation between these two transducers was further indicated by the finding of their in vivo association. This association was, at least in part, dependent on recognition of shc by the SH3 domain of eps8. Our results indicate that eps8 is physiologically part of the EGFR-activated signaling and that its alterations can contribute to the malignant phenotype.

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Specific activation of the cellular Harvey-ras oncogene in dimethylbenzanthracene-induced mouse mammary tumors

Molecular and Cellular Biology ◽

10.1128/mcb.6.11.4104-4108.1986 ◽

1986 ◽

Vol 6 (11) ◽

pp. 4104-4108

Author(s):

S Dandekar ◽

S Sukumar ◽

H Zarbl ◽

L J Young ◽

R D Cardiff

Keyword(s):

Mammary Tumors ◽

3T3 Cells ◽

Mouse Mammary Tumor ◽

Mouse Mammary Tumors ◽

Transforming Activity ◽

Radiation Induced ◽

Genomic Dnas ◽

Nih 3T3 ◽

Adenosine Nucleotide ◽

Nih 3T3 Cells

Genomic DNAs from dimethylbenzanthracene-induced BALB/c mouse mammary tumors arising from the transplantable hyperplastic outgrowth (HPO) line designated DI/UCD transformed NIH 3T3 cells upon transfection. Transforming activity was attributed to the presence of activated Harvey ras-1 oncogenes containing an A----T transversion at the middle adenosine nucleotide in codon 61. DNAs from untreated DI/UCD HPO cells and radiation-induced and spontaneous mammary tumors from the DI/UCD HPO line failed to transform NIH 3T3 cells. The results indicated that the mutation activation of Harvey ras-1 oncogenes was specific to dimethylbenzanthracene treatment in the mouse mammary tumor system.

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Differential early viral gene expression in two stages of human papillomavirus type 16 DNA-induced malignant transformation.

Molecular and Cellular Biology ◽

10.1128/mcb.7.6.2165 ◽

1987 ◽

Vol 7 (6) ◽

pp. 2165-2172 ◽

Cited By ~ 14

Author(s):

S Yasumoto ◽

J Doniger ◽

J A DiPaolo

Keyword(s):

Gene Expression ◽

Human Papillomavirus ◽

Malignant Transformation ◽

Cell Lines ◽

Viral Gene Expression ◽

Viral Gene ◽

3T3 Cells ◽

Hpv 16 ◽

Nih 3T3 ◽

Nih 3T3 Cells

Human papillomavirus (HPV) type 16 DNA induces progressive transformation in NIH 3T3 cells. Two types of cell lines, PM3T3G0 and PM3T3Fo, were isolated by G418 or focus selection, respectively, after transfection of cells by a recombinant HPV 16 DNA carrying the neo gene. These cell lines exhibited distinct phenotypes compared with controls. Saturation densities of PM3T3G0 and PM3T3Fo lines were two- to three- and five- to sevenfold greater than that of control NIH 3T3 cells, respectively. Neither cell type required high serum for growth, in contrast to NIH 3T3 cells. PM3T3G0 lines were premalignant, whereas PM3T3Fo lines manifested tumorigenicity within 2 weeks. Subpopulations of three PM3T3G0 lines underwent progressive transformation as reflected by focus formation. Analysis of HPV 16-specific mRNA species demonstrated that high levels of early and late gene expression were detected in premalignant PM3T3G0 lines, whereas relatively low quantities of selected gene messages were expressed in malignant transformants. Thus, high levels of viral gene expression are not crucial for malignant transformation.

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Induction of Metastatic Phenotype in NIH/3T3 Cells Transfected with DNA from a Metastatic Human Tumor Cell Line

Immune-Deficient Animals in Experimental Medicine ◽

10.1159/000417155 ◽

2015 ◽

pp. 112-117

Author(s):

Wei-gang Fang ◽

Bing-quan Wu

Keyword(s):

Tumor Cell ◽

Cell Line ◽

Human Tumor ◽

Tumor Cell Line ◽

Human Tumor Cell Line ◽

3T3 Cells ◽

Human Tumor Cell ◽

Metastatic Phenotype ◽

Nih 3T3 ◽

Nih 3T3 Cells

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Isolation of cellular genes differentially expressed in mouse NIH 3T3 cells and a simian virus 40-transformed derivative: growth-specific expression of VL30 genes.

Molecular and Cellular Biology ◽

10.1128/mcb.5.10.2590 ◽

1985 ◽

Vol 5 (10) ◽

pp. 2590-2598 ◽

Cited By ~ 21

Author(s):

K Singh ◽

S Saragosti ◽

M Botchan

Keyword(s):

Cell Lines ◽

Simian Virus 40 ◽

Mouse Cell ◽

Simian Virus ◽

Differentially Expressed ◽

Transformed Cells ◽

3T3 Cells ◽

Transformed Cell ◽

Nih 3T3 ◽

Nih 3T3 Cells

We constructed and screened a cDNA library made from simian virus 40 (SV40)-transformed NIH 3T3 cells, and we isolated cDNAs representing genes that are differentially expressed between the parental cell and its SV40-transformed derivative. We found only a small number of cDNAs representing such genes. Two isolated cDNA clones represented RNAs expressed at elevated levels in the transformed cell line in a manner relatively independent of growth conditions. The expression of two other cDNAs was growth specific because transformed cells and nonconfluent parental cells contained higher levels of the homologous RNAs than did confluent, contact-inhibited parental cells. Another cDNA was well expressed in confluent parental and confluent transformed cells, but not in nonconfluent cells. The expression of some of these cDNAs varied strikingly in different mouse cell lines. Thus the genotype or histories of different cell lines can also affect the expression of certain genes. Interestingly, the only cDNA isolated that was expressed exclusively in the transformed cell was from an SV40 message. We focused on a growth-specific cDNA which we show is derived from a mouse endogenous retrovirus-like family called VL30. We sequenced the 3' long terminal repeat (LTR) of this transcriptionally active VL30 gene. This LTR has good homology with other VL30 LTR sequences, but differences occur, particularly upstream of the VL30 promoter. We found that VL30 gene expression varied in different mouse cell lines such that C3H cell lines had very low levels of VL30 transcripts relative to NIH 3T3 cell lines. However, Southern analysis showed that both cell lines had about the same number of VL30 genes homologous to our probe and that the position of the majority of these genes was conserved. We discuss possible explanations for this difference in VL30 expression.

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B-raf, a new member of the raf family, is activated by DNA rearrangement.

Molecular and Cellular Biology ◽

10.1128/mcb.8.6.2651 ◽

1988 ◽

Vol 8 (6) ◽

pp. 2651-2654 ◽

Cited By ~ 89

Author(s):

S Ikawa ◽

M Fukui ◽

Y Ueyama ◽

N Tamaoki ◽

T Yamamoto ◽

...

Keyword(s):

Ewing Sarcoma ◽

Dna Rearrangement ◽

Terminal Portion ◽

3T3 Cells ◽

Complementary Dna ◽

Amino Terminal ◽

Transforming Activity ◽

Nih 3T3 ◽

Transforming Gene ◽

Nih 3T3 Cells

Complementary DNA clones of a putative transforming gene were isolated from NIH 3T3 cells transformed with human Ewing sarcoma DNA. The gene was termed B-raf because it is related to but distinct from c-raf and A-raf. It appears that substitution in the amino-terminal portion of the normal B-raf protein confers transforming activity to the gene.

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Mechanism of activation of the ret proto-oncogene by multiple endocrine neoplasia 2A mutations.

Molecular and Cellular Biology ◽

10.1128/mcb.15.3.1613 ◽

1995 ◽

Vol 15 (3) ◽

pp. 1613-1619 ◽

Cited By ~ 227

Author(s):

N Asai ◽

T Iwashita ◽

M Matsuyama ◽

M Takahashi

Keyword(s):

Cell Surface ◽

Multiple Endocrine Neoplasia ◽

Simian Virus 40 ◽

Simian Virus ◽

3T3 Cells ◽

Endocrine Neoplasia ◽

Transforming Activity ◽

Nih 3T3 ◽

Men 2A ◽

Nih 3T3 Cells

Transforming activity of the c-ret proto-oncogene with multiple endocrine neoplasia (MEN) 2A mutations was investigated by transfection of NIH 3T3 cells. Mutant c-ret genes driven by the simian virus 40 or cytomegalovirus promoter induced transformation with high efficiencies. The 170-kDa Ret protein present on the cell surface of transformed cells was highly phosphorylated on tyrosine and formed disulfide-linked homodimers. This result indicated that MEN 2A mutations induced ligand-independent dimerization of the c-Ret protein on the cell surface, leading to activation of its intrinsic tyrosine kinase. In addition to the MEN 2A mutations, we further introduced a mutation (lysine for asparaginic acid at codon 300 [D300K]) in a putative Ca(2+)-binding site of the cadherin-like domain. When c-ret cDNA with both MEN 2A and D300K mutations was transfected into NIH 3T3 cells, transforming activity drastically decreased. Western blot (immunoblot) analysis revealed that very little of the 170-kDa Ret protein with the D300K mutation was expressed in transfectants while expression of the 150-kDa Ret protein retained in the endoplasmic reticulum was not affected. This result also demonstrated that transport of the Ret protein to the plasma membrane is required for its transforming activity.

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