Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Receptor status, proliferative activity, loss of differentiation, inactivation of tumor suppressor genes, and overexpression of oncogenes are related events that may affect the prognosis of patients with breast cancer. Ninety-seven unselected breast carcinomas were immunostained for estrogen and progesterone receptors, Ki-67 proliferation-associated antigen, p53 tumor suppressor gene product (p53), and c-erbB-2 protein. Immunohistochemical results and clinical data were compared. Altered p53 expression (regarded as indirect indication of inactivating gene alterations) was found in 25.8% of cases and was associated with a high Ki-67 labeling index, high mitotic count, and high histologic grade, with c-erbB-2 overexpression, and with negative estrogen and progesterone receptor status. p53 immunostaining could be found also in cytologic samples and correlated with p53 immunoreactivity on frozen sections of the corresponding tumors. c-erbB-2 protein overexpression was seen in 24.7% of cases and was associated with p53 altered expression and negative receptor status. Double immunohistochemical staining showed p53 and c-erbB-2 immunoreactivity in the same cells. Median and mean +/- standard deviation Ki-67 labeling index values were 15 and 16.32 +/- 10.05, respectively. Ki-67 labeling index was correlated with high mitotic count and was positively associated with histologic grade, negative progesterone receptor status, and p53 expression. Estrogen receptor status was not associated with any histologic or clinical parameters, whereas progesterone receptor status was associated with grading. The direct relation of p53 protein alterations with c-erbB-2 overexpression may be interpreted in light of the multistep model of tumor progression. Cases with altered expression of both p53 and c-erbB-2 proteins could be interpreted as having lost one inhibitory control mechanism of cell proliferation and having gained one activator of the malignant potential. However, in comparing cases with the p53 + c-erbB-2 + phenotype with cases showing positivity for only one of these gene products, no association with higher stages was seen. Detection of p53 altered expression on cytologic samples of malignant tumors may have diagnostic relevance, and p53 immunostaining may prove to be an additional diagnostic criterion in cytologic diagnosis.
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PMID:p53 and c-erbB-2 protein expression in breast carcinomas. An immunohistochemical study including correlations with receptor status, proliferation markers, and clinical stage in human breast cancer. 135 56

Immunohistochemical staining for the p53 protein was performed in 107 snap frozen primary endometrial adenocarcinomas and 15 benign uterine tissues using monoclonal antibody PAb1801. No staining was seen in benign samples, whereas intense nuclear staining of cancer cells consistent with overexpression of the p53 protein was observed in 22 of 107 cancers (21%). p53 overexpression was more frequent in advanced (Stage III/IV) cancers (41%) than in early (Stage I/II) cancers (9%) (P less than 0.001), and also was associated with nonendometrioid histology (P = 0.008), positive peritoneal cytology (P = 0.01), extrauterine metastases (P = 0.003), and negative progesterone receptor status (P = 0.04). To confirm the relationship between p53 overexpression and mutation, p53 mRNA from 8 cancers was reverse transcribed and amplified using the polymerase chain reaction. DNA sequencing revealed point mutations in each of the 5 cancers that overexpressed p53, whereas the wild-type sequence was found in 3 cancers that did not overexpress the protein. Each of the 5 mutations resulted in an amino acid substitution in a highly conserved region of the p53 gene where mutations have been found in other cancers. Further studies are warranted to determine whether the association between p53 overexpression and advanced stage disease is due to accumulation of genetic lesions during tumor progression or whether p53 alterations confer a more virulent phenotype.
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PMID:Overexpression and mutation of p53 in endometrial carcinoma. 154 Sep 70

To study the importance of estrogen availability to growth pattern and other tumor characteristic such as estrogen receptor (ER) and progesterone receptor (PgR) content and histopathology, we have used a human tumor-nude mouse model, in which an ER- and PgR-positive and estradiol-sensitive (stimulated) human endometrial adenocarcinoma was heterotransplanted and serially passed in female (non-oophorectomized) nude mice over a period of one year. Pieces from this tumor were transplanted into oophorectomized nude mice, randomly divided into two groups, one with and one without estradiol treatment (preparation phase). After four weeks, pieces from both these groups were again transplanted into oophorectomized nude mice, each group being randomly allocated to two subgroups, one with and one without estradiol treatment (experimental phase). Tumor growth was measured during the experimental phase, whereas both ER and PgR content and histopathology were analyzed after the experimental phase. Our findings indicate that even short-term growth under estradiol-poor conditions can trigger such progressive changes as reduced steroid receptor content, development of a less differentiated tumor and tendency to enhanced tumor growth. On the other hand, estradiol-rich conditions enhanced ER activation, PgR induction and tumor differentiation in the same tumor line. The estrogenic conditions under which a tumor grows may thus be crucial determinants of tumor progression.
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PMID:Estradiol induced changes in tumor growth and steroid receptor content in a heterotransplanted human endometrial adenocarcinoma. 181 Apr 29

Amplification of HER-2 oncogene was analysed in DNAs obtained from 291 primary human mammary carcinomas. 52/291 (18%) were found to contain amplified HER-2 oncogene. Moderate amplification (2- to 5-fold) was noted in 36/291 (12%). Thirteen tumors (4.5%) had a copy number of 5 to 10. A 10- to 20-fold and greater than 20-fold amplification was observed in 2 and 1 patient, respectively. Sample sizes allowed the determination of estrogen receptor (ER) and progesterone receptor (PgR) levels in 253/291 primary breast cancers. HER-2 gene amplification was noted in 14% of ER+ patients and in 28% of ER- patients, respectively (P = 0.02). Similarly a significantly greater number of PgR- primary mammary carcinoma exhibited an amplification of the HER-2 gene compared to PgR+ cases (22% vs. 16%, P = 0.01). Although statistically not significant, tumors with HER-2 gene amplification were found to have lower levels of ER and PgR. No association of HER-2 amplification with the androgen receptor and EGF receptor was observed. Present data combine to suggest that tumor progression is more stringently controlled by the oncogene upon loss of hormone dependency. Differences found in HER-2 amplification between steroid receptor positive and negative tumors could be helpful to define a specific subset of women to whom adjuvant therapy should be directed.
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PMID:HER-2 amplification, steroid receptors and epidermal growth factor receptor in primary breast cancer. 291

Eleven women with advanced ovarian cancer were treated with a sequential and combined hormonal regimen designed to induce and bind tumor progesterone receptors. Two partial responses were seen, and two patients with a recent history of rapid tumor progression achieved disease stabilization. One patient experienced a transient ischemic cerebrovascular episode while on therapy, and a second patient discontinued therapy because of nausea. The regimen was able to induce progesterone receptors in vivo. One patient had no progesterone receptor in a pretreatment tumor biopsy, but did have a high titer of receptors after her first cycle of treatment.
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PMID:Estrogen and progestogen therapy in advanced ovarian cancer: preliminary report. 665 79

CD44 is a transmembrane glycoprotein occurring in several isoforms with different extracellular regions. The various transcripts are encoded by one gene locus containing 20 exons, of which at least 10 can be alternatively spliced in nascent RNA. Isoforms encoded by the variant exons (termed CD44v) are highly restricted in their distribution in nonmalignant tissue as opposed to the standard form of CD44 (CD44s) abundant in many tissues. Specific variant isoforms containing exon 6v have been shown to render nonmetastatic rat tumor cells metastatic. Based on the prominent role in rat metastasis formation, CD44v isoforms were suggested to be involved in human tumor progression. Correlations between prognosis and expression of CD44v have been reported for gastric and colon carcinoma, for non-Hodgkin's lymphoma, and recently for breast carcinoma. We evaluated the expression of CD44 isoforms in node-positive (n = 119) and node-negative (n = 108) cases of breast carcinoma by immunohistochemistry using CD44v exon-specific mAbs. In a subset of 43 cases of high-risk patients, reverse transcription-PCR was used to determine the exon composition of the transcripts. Protein and RNA expression data were probed statistically for their correlation to survival of the patients and clinical risk factors. In contrast to recently published data (M. Kaufmann et al., Lancet, 345: 615-619, 1995), in our cohort disease-free and overall survival data did not indicate significant correlations with the expression of the analyzed isoforms in univariate and multivariate analyses. Comparison of CD44 protein expression with established clinical risk factors for survival such as tumor size (pT1+pT2) and histological grading revealed correlations with the presence of CD44s (P = 0.02 and P = 0.03, respectively) and CD44-9v (P = 0.05 for histological grading). Carcinoma tissues with elevated estrogen and progesterone receptor levels showed positive correlation with CD44-6v (P = 0.001), while a trend for significant coexpression of CD44s and CD44-9v isoforms was observed in estrogen receptor-positive tissues (P = 0.08 and 0.06, respectively). In breast cancer, CD44s, CD44-9v, and CD44-6v are apparently markers for cellular differentiation but not for tumor progression. Our data suggest that steroid hormone receptors may be associated with the in vivo expression of CD44-6v-containing isoforms in human mammary carcinoma.
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PMID:CD44 isoforms correlate with cellular differentiation but not with prognosis in human breast cancer. 758 12

Estrogen (ER) and progesterone receptor (PgR) positive breast tumors often respond to tamoxifen, but ultimately progress as they become tamoxifen resistant. An accurate assessment of receptor status in specimens from tamoxifen-resistant patients could help to understand potential mechanisms of resistance and to predict response to second line hormonal therapies. However, since tamoxifen itself can affect ER and PgR determinations, assay results can be misleading. We measured ER and PgR by both ligand binding (LBA) and immunohistochemical (IHC) assays in 34 tumors from patients on tamoxifen, 30 of whom were displaying resistance to the drug. These tumors were classified into several receptor phenotypes. Eleven patients, 8 of whom were clearly progressing, expressed both receptors while on tamoxifen. ER was significantly less often negative when measured by IHC, suggesting that ER status by LBA was falsely negative in this group due to receptor occupancy by tamoxifen. Six patients had no detectable ER by LBA or IHC but still expressed PgR. The presence of PgR suggests that ER could still be functional, though undetectable, in these tumors, or that PgR is constitutively expressed by them. Finally, 12 patients were ER and PgR-negative by both assays, suggesting hormonal independence as the mechanism for resistance in this group. In a subset of patients with receptor assays both prior to tamoxifen and at the time of progression while taking the drug, we found that most ER-positive tumors converted to an apparent ER-negative status when assayed by LBA, while PgR status frequently remained unchanged. The continued expression of ER and/or PgR in many patients with tumor progression on tamoxifen indicates that mechanisms for resistance other than receptor loss are common in breast cancer.
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PMID:Measurement of steroid hormone receptors in breast cancer patients on tamoxifen. 825 48

Recent evidence suggests that the expression of estrogen receptor (ER) variants in breast cancer may interfere with wild-type (wt) ER function and be related to tumor progression and resistance to hormone treatment. One of these variants, ER delta E5, lacking that part of the hormone-binding domain encoded by exon 5, has previously been identified in breast tumors with the unusual estrogen receptor negative (ER-) and progesterone receptor positive (PgR+) phenotype and found to possess constitutive and hormone-independent transcriptional activity. Using a ribonuclease protection assay, we analyzed 27 breast tumors and 4 breast cell lines for the presence of this variant. We found the ER delta E5 variant to be expressed, not only in all of three ER-/PgR+ tumors but also in 19 of 20 ER+/PgR+ or ER+/PgR- tumors. Moreover, the variant was always coexpressed with and often in excess of wtER. ER delta E5 was also found in three breast cancer cell lines (MCF7, T47D, and ZR75-1), although to a lesser extent than wtER. A complete absence of both ER delta E5 and wtER was noted in four ER-/PgR- tumors and one normal breast cell line (HBL-100). Thus, our data suggest that the occurrence of ER delta E5 in breast cancer may represent a critical stage in tumor progression to autonomy.
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PMID:An exon 5 deletion variant of the estrogen receptor frequently coexpressed with wild-type estrogen receptor in human breast cancer. 826 97

We determined DNA content, S-phase fraction, and estrogen (ER) und progesterone receptor (PR) levels in 36 stage I endometrial adenocarcinomas and in 22 hyperplastic lesions to obtain information on the genesis and progression of endometrial malignancy. DNA aneuploidy was detected in 12/36 (33%) carcinomas and in none of the hyperplastic lesions. DNA aneuploidy was significantly more common in poorly and moderately differentiated carcinomas than in the well-differentiated ones. Similarly, the highest number of cells in S-phase were found in poorly and moderately differentiated carcinomas, whereas well-differentiated carcinomas and all hyperplasias had an equally small S-phase fraction. Mean ER and PR levels were highest in hyperplastic lesions, especially those with atypical features, whereas carcinomas of all grades had significantly lower values. Thus, it is likely that the loss or decreased expression of steroid receptors is an early event during carcinogenesis in human endometrium, whereas an increase in the cell proliferation rate and the formation of DNA aneuploidy occur later during tumor progression.
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PMID:DNA ploidy, cell proliferation and steroid hormone receptors in endometrial hyperplasia and early adenocarcinoma. 849 64

The whey acid protein (WAP) is a major mouse milk protein and its gene expression is induced by various lactotrophic hormones (eg, estrogen, progesterone). Transgenic animals harboring the early SV40 coding region (T/t-antigen) under the transcriptional control of the WAP promoter develop breast cancer after the first lactation period. The tumor cells synthesize the SV40 T-antigen with a high efficiency indicating that WAP-SV-T expression escapes down-regulation after the lactation period. However about 5-10% of the tumors became T-antigen negative during tumor progression and WAP-SV-T expression was only demonstrable by PCR analysis. Both T-antigen positive and negative tumor cells expressed the estrogen and progesterone receptor at a comparable rate, indicating that hormone receptor levels do not determine expression of the WAP-SV-T transgene. Furthermore, WAP and WAP-SV-T gene expression are not restricted to the pregnancy-lactation period. Virgin animals also express both genes with a low efficiency and about 70% of these animals also developed T-antigen positive breast tumors. The tumor rate however was strongly reduced in ovariectomized animals, indicating that the ovary hormones play a critical role in breast cancer formation.
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PMID:SV40 T-antigen induces breast cancer formation with a high efficiency in lactating and virgin WAP-SV-T transgenic animals but with a low efficiency in ovariectomized animals. 863 5


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