Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P04626 (
erbB-2
)
5,251
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The effect of alpha 2b-interferon administration on liver regeneration after partial hepatectomy in male Wistar rats was examined 24 hours after the operation. Tritium thymidine incorporation into liver DNA, liver mass restitution, mitotic index, and nuclear expression of proliferating cell nuclear antigen were determined as indexes of hepatic proliferation. Both early and late alpha 2b-interferon administration, 2 and 12 hours, respectively, after partial hepatectomy, at a dose of 3.3 x 10(4) IU per kg body weight, suppressed tritium thymidine incorporation and liver mass restitution (p < 0.001) when compared with that in untreated partially hepatectomized rats. The enzyme thymidine kinase (EC 2.7.1.21), a rate-determining enzyme of DNA biosynthesis, has been implicated in the suppression of proliferation in interferon-treated cell cultures. However, in the above-mentioned in vivo model of controlled cellular proliferation, thymidine kinase activity was not affected by alpha 2b-interferon administration, whereas DNA biosynthesis was inhibited. These findings, in contrast to previous observations in in vitro models, show that the inhibition of the in vivo liver regeneration by alpha 2b-interferon is not due to the inhibition of thymidine kinase activity. The expression of the cell cycle-related genes' products
c-myc
, p53, and c-
erbB-2
proteins--which increase during the prereplicative phase that precedes DNA synthesis--was affected by interferon administration, being in accordance with liver proliferative status.
...
PMID:Alpha 2b-interferon inhibits rat liver regeneration after partial hepatectomy without affecting thymidine kinase activity. 773 25
We recently proposed a quantitative PCR procedure for the absolute measurement of c-
erbB-2
oncogene amplification, based on the simultaneous polymerase chain reaction (PCR) amplification of the target gene and of a competitor DNA molecule acting as internal standard. To increase the number of assayable oncogenes and the accuracy of the quantitative comparison of gene amplification degree within the same tumor, we have now constructed a single synthetic competitor for int-2,
c-myc
, N-myc epidermal growth factor receptor, and c-
erbB-2
genes, and for the reference gene beta-globin. This competitor was constructed by a two-step recombinant PCR procedure and inserted as a 297-bp sequence in a plasmid. The order of primer insertion was designed to obtain competitors of comparable sizes to those of the respective genomic targets, but still easily recognizable from the latter ones by gel electrophoresis. The clone competitor was tested to evaluate the linearity range for each assay. The present application of quantitative PCR based on a multiple competitor represents the first approach for the achievement of a single reagent for the evaluation of a panel of genes potentially amplified in human tumors.
...
PMID:Gene amplification for c-erbB-2, c-myc, epidermal growth factor receptor, int-2, and N-myc measured by quantitative PCR with a multiple competitor template. 776
In order to get a better understanding of expressions of multiple oncogenes and their possible roles in human hepatocarcinogenesis, 379 cases of liver tissues were investigated immunohistochemically. EGF receptors were immunolocalized mainly in the sinusoidal endothelial cells. They might not take part in the development of hepatocellular carcinoma (HCC), c-myc protein was showed to be expressed in cancer cells and the hepatocytes in the so-called "large-cell dysplasia" and in ductular metaplasia (DM). Its expression was also observed in some zone II hepatocytes of hepatic accini in 21% of normal liver tissues, which indicated that
c-myc
expression might also be related to the proliferation of mature hepatocytes. The positivity rate of c-
erbB-2
product was shown to be highest among the oncogenic genes examined in this study. The positivity was observed in small polygonal liver cells (SPLCs) and the hepatocytes were observed in SCD and in DM. The expression level of c-
erbB-2
oncogene in HCC cells was higher significantly than in normal hepatocytes, but lower than in SPLCs, the hepatocytes in SCD and in DM. We suggest that c-
erbB-2
gene activation may play an important role not only in HCC genesis, but also in DM. Insulin-like growth factor II (IGF II), an oncofetal hepatocellular growth factor, was immunolocalized in the cancer cells, SPLCs and the hepatocytes in SCD, which indicated that activation and hyperexpression of IGF II gene might be responsible for the prominent proliferation of SPLCs and SCD, a crucial step in malignant transformation of hepatocytes.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:[Expression of c-myc, c-erbB-2, insulin-like growth factor II andepidermal growth factor receptor in hepatitis B, cirrhosis and hepatocellular carcinoma]. 778 Aug 18
A three-step immunoperoxidase staining technique was used in order to estimate the immunohistochemical expression of K-ras, c-fos,
c-myc
and c-
erbB-2
oncoproteins, in paraffin sections of 20 patients, with histologically proven adenocarcinoma of the pancreas. The two oncogenes that were found to be associated with pancreatic adenocarcinoma were K-ras and c-
erbB-2
. in 15 patients (75%) and four patients (20%), respectively. Positive immunostaining was intense, cytoplasmic and was noted in a great percentage of cancer cells. The same model of expression was observed in the examined cases of metastatic tissue from liver and lymph node metastases. The expression of myc and fos oncogenes was nuclear, weak and was observed in a small number of patients.
...
PMID:Oncogenes in cancer of the pancreas. 778 91
The prognostic significance of the three genes most frequently amplified in breast tumors was investigated by multivariate analysis in a retrospective study of 112 primary human breast cancers. These three genes,
c-myc
, int-2/FGF3 (a marker for the 11q13 amplicon), and c-
erbB-2
/neu, were amplified in 37%, 14%, and 10% of breast tumors studied, respectively. Amplification of the
c-myc
gene was not related to metastasis-free survival in the total population but was a discriminant prognostic indicator in premenopausal patients. Int-2/FGF3 gene amplications were good indicators of prognosis, especially in premenopausal patients, and also in lymph-node-positive and steroid-receptor-negative patients. Int-2/FGF3 amplification and progesterone receptor status together proved to be the only independent variable predictive of metastasis-free survival. The risk of relapse in the subgroup of progesterone-receptor-negative patients was 5 times greater for those with int-2/FGF3 amplification than for those without this alteration. Amplifications at the c-
erbB-2
/neu locus were not significantly associated with any standard prognostic indicator or with an increased risk of recurrence. These results suggest that the combined use of classical prognostic factors and molecular markers may improve prognostic value and be applicable to patients with specific tumor phenotypes.
...
PMID:Int-2/FGF3 amplification is a better independent predictor of relapse than c-myc and c-erbB-2/neu amplifications in primary human breast cancer. 789 57
Triplex-forming oligonucleotides (TFOs) have been shown to bind to target DNA sequences in several human gene promoters such as the
c-myc
oncogene, the epidermal growth factor receptor, and the dihydrofolate reductase genes. TFOs have been shown to inhibit transcription in vitro and gene expression in cell culture of the
c-myc
and other genes. The
HER-2/neu
oncogene, which is overexpressed in breast cancer and other human malignancies, contains a purine-rich sequence in its promoter, which is favorable for purine:purine:pyrimidine (R:R:Y) triplex formation. Although its function in the
HER-2/neu
promoter is unknown, this purine-rich site is homologous to a protein-binding sequence in the promoter of the epidermal growth factor receptor that is necessary for efficient transcription of this gene. We have shown that this sequence is a site for nuclear protein binding by incubation with a crude nuclear extract. We describe the formation of an interstrand triplex using a purine-rich oligonucleotide antiparallel to this purine-rich target sequence of the
HER-2/neu
promoter. Triplex formation by the oligonucleotide prevents protein binding to the target site in the
HER-2/neu
promoter in vitro. We have shown that this oligonucleotide is a potent and specific inhibitor of
HER-2/neu
transcription in an in vitro assay. The triplex target site contains a single pyrimidine base that does not conform to the R:R:Y triplex motif. In an attempt to abrogate the potentially destabilizing effects of this pyrimidine base on triplex formation, we have substituted an abasic linker for the pyrimidine residue in the triplex forming oligonucleotide. Triplex formation with the modified oligonucleotide appears to occur with approximately equivalent binding affinity. Triplex formation in the
HER-2/neu
oncogene promoter prevents transcription in vitro and may represent a future modality for specific inhibition of this gene in vivo.
...
PMID:Triplex formation inhibits HER-2/neu transcription in vitro. 790 Dec 37
Nineteen paraffin-embedded breast cancer tissue samples selected for long survival (more than 5 years) were analysed for detecting the amplification of the c-
erbB-2
(Her-2/neu) oncogene by Polymerase Chain Reaction (PCR). Strong correlation was elucidated between c-
erbB-2
amplification and survival; such correlation was also observed with histopathologic types and nuclear grading. Because of the similarity of the breast and ovarian cancer in the etiology of the diseases, amplification of c-
erbB-2
,
c-myc
and Ki-ras genes was examined in 32 ovarian carcinoma samples (stage I-IV). In ovarian carcinomas c-
erbB-2
amplification occurred in 34% (11/32) of the fresh tumour samples, and correlation between amplification and clinical staging at P < 0.05 significance level was observed. Amplification of
c-myc
was detected in 9% (3/32) and none of the tumours showed amplification of Ki-ras.
...
PMID:Oncogene patterns in breast and ovarian carcinomas. 790 45
To determine the frequency and clinicopathologic correlates of chromosome 11q13 amplification in breast carcinoma, DNA from 50 invasive tumors was analyzed by Southern blot hybridization using probes for the 11q13 loci bcl-1, PRAD1, hst1, EMS1, and GST-pi, as well as oncogenes c-
erbB-2
and
c-myc
. Sixteen tumors (32%) were amplified for one or more loci. Seven tumors (14%) showed amplification of 11q13 loci; six of these were coamplified with either c-
erbB-2
(three),
c-myc
(two), or both (one). Nine additional tumors (18%) were amplified for c-
erbB-2
, and three of these were coamplified with
c-myc
. None showed
c-myc
amplification alone. Tumors with 11q13 amplification showed equivalent degrees of bcl-1, PRAD1, hst1, and EMS1 amplification, delineating an approximately 800-kb amplicon. GST-pi was inconsistently amplified, evidence that it lies outside the amplicon defined by bcl-1 and EMS1. Amplification of 11q13 was unassociated with patient age, tumor size, axillary lymph node status, hormone receptors, DNA content, histologic grade, mitotic rate, nuclear pleomorphism, or tubule formation.
c-myc
amplification correlated with the lack of tubule formation (p = 0.04), whereas c-
erbB-2
amplification correlated with axillary lymph node positivity (p = 0.04), high histologic grade (p = 0.003), increased nuclear pleomorphism (p = 0.008), and a high mitotic rate (p = 0.02). The frequency of coamplification of 11q13 loci,
c-myc
, and c-
erbB-2
contradicts previous proposals that amplification of these genes occurs in independent subsets of breast carcinoma. Extended clinical followup will be necessary to determine whether 11q13 amplification has prognostic utility in invasive breast cancer.
...
PMID:Chromosome 11q13, c-erbB-2, and c-myc amplification in invasive breast carcinoma: clinicopathologic correlations. 790 28
Molecular biologic studies have shown that human papillomavirus (HPV), some oncogenes and tumor suppressor genes are associated with uterine cervical carcinogenesis. We examined HPV DNA typing and its gene expression, oncogenes (
c-myc
, EGF-R,
c-erb B2
) and p53 in cervical dysplasia and cancer with molecular biologic, immunohistochemical technique and binding assay to establish a gene diagnosis of uterine cervical cancer. The HPV study revealed that HPV DNA was detected at a high frequency at a higher grade of dysplasia and in the early stage of cervical cancer; especially HPV type 16 was associated with cervical carcinogenesis. In the oncogene study,
c-myc
gene overexpression was recognized in the advanced stage of cervical cancer. The other oncogene and p53 were found in a low frequency and were non-specific genes in cervical cancer. These findings indicated that HPV DNA diagnosis is a useful tool for screening the high risk group of cervical precancerous lesions and that oncogene detection might be useful in determining the biological behavior of a malignant tumor.
...
PMID:[Gene diagnosis of uterine cervical cancer]. 790 55
The expression of transforming growth factor-alpha (TGF-alpha), epidermal growth factor receptor (EGF-R) and oncogenes c-
erbB-2
, c-H-ras,
c-myc
, as well as estrogen (ER) and progesterone (PR) receptors were studied immunohistochemically in the tissue of 21 benign and 58 malignant human breast lesions. Twenty nine (50%) of 58 carcinomas were positive for EGF-R and c-
erbB-2
product, 55 (94.8%) for
c-myc
product, 9 (15.5%) for c-H-ras product and 17 (29%) for TGF-alpha. Eighteen of 58 (31%) carcinomas were estrogen receptor positive and 22 (38%) were positive for progesterone receptor. No correlation was found between expression of each investigated parameter and the clinical stage or degree of histological differentiation of the carcinomas. However, a significant positive correlation was observed between lymph node involvement and c-
erbB-2
and EGF-R/c-
erbB-2
positive tumors. A strong correlation was also observed between high levels of EGF-R and low levels of estrogen receptor. In 15 of 17 cases we found simultaneous expression of EGF-R and TGF-alpha. We also found interesting patterns in concomitant expression of the investigated parameters suggesting a possible cascade of events that occur in breast cancer cells.
...
PMID:Immunohistochemical detection of TGF-alpha, EGF-R, c-erbB-2, c-H-ras, c-myc, estrogen and progesterone in benign and malignant human breast lesions: a concomitant expression. 791 21
<< Previous
1
2
3
4
5
6
7
8
9
10
Next >>