Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
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Target Concepts:
Gene/Protein
Disease
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Query: UNIPROT:P04626 (
erbB-2
)
5,251
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Thirty-five patients with ovarian tumors operated on between December, 1989 and June, 1991 were studied to detect K-ras codon 12 point mutation (PM). (1) Five of 35 ovarian tumors (14.3%) disclosed K-ras PM at codon 12 and all the PM cases were in transition from
GGT
to GAT. On the other hand only one case (5.3%) with K-ras oncogene amplification was found and no C-myc or
erbB-2
amplification was detected. (2) The incidence of PM according to clinical stages was seen in 3 of 11 stage I cases (27.3%), in 1 of 3 stage II cases (33.3%), in 1 of 14 stage III cases (7.1%) and in neither of 2 stage IV cases. PM was therefore seen in relatively early stages. (3) The occurrence of PM according to the histologic type was found in 3 of 16 serous tumors (18.8%), in 2 of 5 mucinous tumors (40.0%) and in none of 7 clear cell carcinomas or 2 endometrioid carcinomas. (4) Concerning the relation of PM to the involvement of serosal surface of ovarian tumors and to the ascitic cytology, no particular correlation was observed in our study. (5) Regarding the cytologic findings in imprint smears of the tumors in reference to PM, such as nuclear size, shape, N/C ratio, chromatin pattern, nucleolar size and number, the cases with PM tended to have more multiple nucleoli than PM negative cases. No other findings seemed to indicate the clinical progress of cancer. In conclusion, our study indicated that PM in ovarian cancers was a relatively early event in carcinogenesis.
...
PMID:[Studies on the point mutation of ras oncogene in ovarian tumor]. 825 28
To directly compare the expression patterns of different proteins known to be altered during mouse skin carcinogenesis, serial sections of normal and hyperplastic skin and tumors from various stages of 7,12-dimethylbenz[a]anthracene-initiated, 12-O-tetradecanoylphorbol-13-acetate-promoted female SENCAR mice were examined by immunohistochemistry. In untreated, normal mouse skin, keratin 1 (K1) and transforming growth factor-beta1 (TGFbeta1) were strongly expressed in the suprabasal layers, whereas integrin alpha6beta4 was expressed only in basal cells and only moderate staining for transforming growth factor-alpha (TGFalpha) was seen. In hyperplastic skin, TGFalpha expression became stronger, whereas expression of another
epidermal growth factor (EGF) receptor
ligand, heparin-binding EGF-like growth factor (HB-EGF), was strongly induced in all epidermal layers from no expression in normal skin. Likewise, the gap-junctional protein connexin 26 (Cx26) became highly expressed in the differentiated granular layers of hyperplastic skin relative to undetectable expression in normal skin. Expression of cyclin D1 in the proliferative cell compartment was seen in all benign and malignant tumors but not in hyperplastic skin. Beginning with very early papillomas (after 10 wk of promotion), expression of alpha6beta4 in suprabasal cells and small, focal staining for keratin 13 (K13) were seen in some tumors. Later (after 20-30 wk), focal areas of
gamma-glutamyl transpeptidase
(
GGT
) activity appeared in a few papillomas, whereas TGFbeta1 expression began to decrease. Cx26 and TGFalpha staining became patchier in some late-stage papillomas (30-40 wk), whereas suprabasal alpha6beta4, K13, and
GGT
expression progressively increased and K1 expression decreased. Finally, in squamous cell carcinomas (SCCs), there was an almost complete loss of K1 and a further decline in TGFalpha, HB-EGF, TGFbeta1, and Cx26 expression. On the other hand, almost all SCCs showed suprabasal staining for alpha6beta4 and widespread cyclin D1 and K13 expression, whereas only about half showed positive focal staining for
GGT
activity.
...
PMID:Changes in protein expression during multistage mouse skin carcinogenesis. 932 43
The Kirsten-ras (onco)gene codes for a GTP-binding membrane protein that is involved in signal transduction. Activated ras triggers a cascade of protein-phosphorylations that ultimately lead to cell proliferation. Ras-mutations are the main cause for adenocarcinomas of the pancreas besides some mutations in the tumor suppressor gene p53 and the c-
erbB-2
oncogene. The site of ras mutations in pancreatic cancer is restricted to codon 12 that normally encodes a glycine. For analysis of codon-12 mutations, DNA is extracted from cells in pancreatic fluid and amplified by PCR. Because most of these cells originate from normal tissue with only a few tumor cells in the fluid, "enrichment PCR" must be utilized: In a first round of the PCR, ras sequences from all cells are amplified. By utilizing an appropriate restriction enzyme, wild-type sequences can be digested and the remaining fragments containing mutated sequences be amplified again. An artificial restriction site must be introduced by the 5'primer (...GGA CCT
GGT
...) for an enzyme (BstNI) (5'CC!WGG 3') to differentiate between wild-type sequence (...GGA GCT
GGT
...) (during amplification, the G is replaced by a C) and mutated sequences (_...GGA GCT (GTT), (CGT), (CCT), etc.). The necessary manipulations pose a considerable risk for contamination for the second round of the PCR procedure. Therefore, we considered whether it would be feasible to perform the restriction digest simultaneously with the first PCR reaction, and avoiding the second round altogether. The results of our experiments demonstrate that one tumor cell in 1000 normal cells can be determined readily, paralleling the results with the original two step-assay. The restriction enzyme used to enrich mutated sequences is stable long enough to be included into the PCR procedure. By this, wild-type sequence amplicons are digested while they are formed and mutated sequences can be enriched selectively.
...
PMID:Restriction digest PCR (RD-PCR) for the analysis of gene mutations. Application to Ki-ras. 980 67
A real-time PCR technique with automated computerized analysis (TaqMan ) was tested to detect K-ras mutations in 66 patients suffering from NSCLC. This technology is characterized by high reproducibility of data and a time-saving analysis procedure. In 11% (7/66) of the tumour specimens and 2% (1/58) of adjacent tumour-free lung specimens a K-ras codon 12 mutation was detected. In adenocarcinomas containing > or =40% tumour cells, however, K-ras mutations were seen in 25% of the cases. The point mutations detected in tumours were
GGT
right curved arrow TGT in five cases and
GGT
right curved arrow GTT in two cases. As compared with immunohistochemical parameters, the K-ras mutated group was characterized by a c-
erbB-2
negativity (p=0.04) and a smaller number of c-erbB-3 (p=0.02) positive cases. EGFR, bcl-2, p53, Ki-67 and p120 expression did not differ significantly. Determination of the K-ras point mutations by automated TaqMan PCR in NSCLC tumour specimens is feasable and highly specific. Due to its high throughput capacity this method represents a valuable tool for routine screening.
...
PMID:Automated real-time PCR to determine K-ras codon 12 mutations in non-small cell lung cancer: comparison with immunohistochemistry and clinico-pathological features. 1296 94