Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0677930 (primary tumor)
 20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The ether lipid 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (ET-18-OCH3; Edelfosine) has been shown to be a rapid inducer of apoptosis in human leukemic cells and has been considered as a promising drug in cancer treatment. Here we have found that ET-18-OCH3 induced apoptosis not only in human tumor cell lines but also in primary tumor cell cultures from cancer patients. Human leukemic cells were highly sensitive to ET-18-OCH3, whereas normal cells remained unaffected. Among the distinct modifications of the ET-18-OCH3 molecule assayed, we found that substitutions in positions sn-2 and sn-3 of the glycerol backbone resulted in a complete loss of its capacity to induce apoptosis, highlighting the importance of the molecular structure of ET-18-OCH3 in its apoptotic effect. Induction of apoptosis by ET-18-OCH3 was very well correlated with the uptake of this ether lipid. ET-18-OCH3-resistant 3T3 fibroblasts became sensitive and incorporated significant amounts of the ether lipid following transformation with the SV40 virus. ET-18-OCH3-induced apoptosis as well as ET-18-OCH3 uptake were not mediated through binding of the ether lipid to the platelet-activating factor receptor. Overexpression of bcl-2 or bcl-xL by gene transfer in the human erythroleukemic HEL cells abrogated apoptosis induced by ET-18-OCH3. ET-18-OCH3 did not affect the expression of bcl-2, bcl-xL, or bax in HEL and HL-60 human leukemic cells but induced expression of c-myc, an important effector of apoptosis in several systems. Thus, ET-18-OCH3 behaves as a potent and highly selective antitumor drug able to induce an apoptotic pathway of cell death in tumor cells but not in nonmalignant cells.
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PMID:Selective induction of apoptosis in cancer cells by the ether lipid ET-18-OCH3 (Edelfosine): molecular structure requirements, cellular uptake, and protection by Bcl-2 and Bcl-X(L). 910 20

We established and characterized a new human synovial sarcoma cell line, SN-SY-1, derived from a monophasic fibrous synovial sarcoma excised from the abdominal wall of a 21-year-old man. We maintained the cell line for over 35 passages in vitro. The SN-SY-1 cells in vitro exhibit spindle and polygonal shapes and join to form an epithelial plaque. SN-SY-1 maintained a consistent karyotype: 46,t(X;18)(p11.2;q11.2), Y, t(6;8) (q13-15;q11-13), the same as that of the primary tumor specimen. RT-PCR assay for chimeric SYT-SSX transcripts followed by digestion with restriction enzymes revealed SYT-SSX1 fusion protein. An immunohistochemical study revealed expression of bcl-2 protein in the SN-SY-1 cell line, in vitro and in vivo. However, DNA analysis showed no rearrangement of the bcl-2 gene, and expression of bcl-2 mRNA was low. Why bcl-2 protein was expressed in this synovial sarcoma was not clarified.
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PMID:Establishment and characterization of a new synovial sarcoma cell line, SN-SY-1: special reference to bcl-2 protein and SYT-SSX1 hybrid transcripts. 937 64

We unexpectedly observed strong nuclear overexpression of bcl-2 protein in advanced stomach cancer. As far as we know, such expression has not yet been reported. To investigate the significance of nuclear expression of bcl-2 protein in gastric carcinoma, we immunohistochemically analyzed bcl-2 overexpression in a gastric carcinogenic sequence, including 19 tubular adenomas (TA), 20 early carcinomas (EGC), and 20 advanced carcinomas (AGC). While TA displayed a specific granular and supranuclear cytoplasmic staining pattern, adenocarcinomas showed a strong nuclear staining pattern. Nuclear staining of bcl-2 was observed in 50% of AGC, 30% of EGC, and 10% of TA; cytoplasmic staining, on the other hand, was observed in all TA, 5% of EGC, and 10% of AGC. Nuclear bcl-2 overexpression differed according to the histologic type of AGC, occurring in 67% of the diffuse type and 25% of the moderately-to-well differentiated type. In the diffuse type, nuclear bcl-2 positive AGC predominated. In metastatic lesions, the pattern of bcl-2 immunostaining was almost identical to that seen in primary tumor. These results suggest that nuclear expression of bcl-2 may be related to malignant transformation in the stomach and is frequently associated with diffuse type advanced gastric adenocarcinomas.
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PMID:Nuclear overexpression of bcl-2 oncoprotein during the progression of human stomach cancer. 961 Jun 15

To study the genetic basis of tumor progression, we have screened 37 hormone-refractory prostate carcinomas for genetic changes by comparative genomic hybridization (CGH). All recurrent tumors showed genetic aberrations, with a mean total number of changes per tumor of 11.4 (range, 3 to 23). The most common genetic aberrations were losses of 8p (72.5%), 13q (50%), 1p (50%), 22 (45%), 19 (45%), 10q (42.5%), and 16q (42.5%) and gains of 8q (72.5%), 7q (40%), Xq (32.5%), and 18q (32.5%). The CGH results were further validated with fluorescence in situ hybridization (FISH) using probes for pericentromeric regions of chromosomes 7, 8, and 18 as well as probes for caveolin (7q31), c-myc (8q24), and bcl-2 (18q21.3). In addition, the samples had previously been analyzed for androgen receptor gene copy number. CGH and FISH results were concordant in 78% of cases. Seventeen of twenty-two tumors showed an increased copy number of c-myc by FISH. However, only 5 of 17 (29%) of the cases showed high-level (more than threefold) amplification. Both CGH and FISH findings suggested that in most of the cases 8q gain involves the whole q-arm of the chromosome. Four of seventeen (24%) cases showed increased copy number of bcl-2 by FISH; however, no high-level amplifications were found. To evaluate the clonal relationship of the primary and recurrent tumors, six primary-recurrent tumor pairs from the same patients were studied by CGH. In three of six cases (50%), the recurrent tumor had more than one-half of the aberrations found in the corresponding primary tumor, indicating a close clonal relationship. In the rest of the cases, such a linear clonal relationship was less evident. Altogether, these results suggest that recurrent prostate carcinomas are genetically unstable. The resulting heterogeneity may well underlie the poor responsiveness of hormone-refractory tumors to treatment.
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PMID:Genetic alterations in hormone-refractory recurrent prostate carcinomas. 966 74

Purpose of our study was to develop a reliable model to define clinical stage I nonseminomatous germ cell tumors (NSGCT) being at low risk and at high risk for occult retroperitoneal metastases based on pathohistological and immunohistochemical parameters in order to stratify the therapeutic approach. 3-5 paraffin-embedded formalin fixed tissue blocks of 149 clinical stage I NSGCT were available from all patients and were analyzed for histopathological features associated with pathological stage: presence/absence of vascular invasion, presence/absence of tunical invasion, percentage of each histological cell type present in the primary tumor. Immunohistochemical expression of MIB-1, p53, bcl-2, cathepsin D and e-cadherin was evaluated using a semiquantitative scoring ystem. Statistical analysis was performed by univariate and multivariate logistic regression models. Percentage of embryonal carcinoma [%EC (p < 0.001)] and presence of vascular invasion [VI (p < 0.0001)] were the most significant independent risk factors associated with pathological stage II disease. Combination of %EC and VI allowed correct prediction of final pathological stage in 88% of patients. Cut-off values including both variables identified correct pathological stage in 131/149 patients (88%). Less than 45% EC and absence of VI correctly identified pathological stage I disease in 91.5%; more than 80% EC and presence of VI correctly predicted pathological stage II in 88% of the patients. %EC and presence/absence of VI appear to be reliable prognosticators to identify both patients at high risk and at low risk for occult retroperitoneal disease. P53, bcl-2, MIB-1, cathepsin D and e-cadherin did not appear to be of prognostic value in clinical stage I NSGCT.
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PMID:[Histopathologic and biological prognostic factors of clinical stage I non-seminomatous germ cell tumors. Implications for risk-adjusted therapy]. 1023 39

Within the past 5 years, research has increasingly addressed molecular alterations in prostate cancer (CaP). Mutations of tumor suppressor gene p53 have been found in a variety of cancers, including urologic neoplasms. Several studies have been conducted on CaP specimens, citing frequencies of p53 alterations in localized cancers ranging from 4 to 60% and with more advanced hormone refractory disease, as high as 94%. The majority of studies have revealed a low percentage of p53 abnormalities in early-stage (clinically organ-confined) CaP. The overwhelming bulk of evidence suggests that the frequency of p53 abnormalities does increase with disease progression and is highest in tissues from patients with hormone-refractory prostate cancer. More recently, our group and others have found that focal p53 expression in the primary tumor by immunohistochemistry is predictive of cancer recurrence after radical prostatectomy. bcl-2 is an oncogene critically involved in the apoptosis, or programmed cell death. Overexpression of bcl-2 protein by immunohistochemistry has been commonly detected in advanced hormone refractory CaP. Our group recently has also shown that bcl-2 protein expression in primary CaP is a predictor of cancer recurrence after radical prostatectomy. Furthermore, the combination of p53 and bcl-2 protein expression were both independent predictors of recurrence after surgery. Most recently, we have shown that even though p53 and bcl-2 are predictive biomarkers when sampling the radical prostatectomy specimen, they are not useful to predict postoperative recurrence when sampling the pretreatment needle biopsy. Ki-67 is an antigen of cellular proliferation. Immunohistochemical staining for Ki-67 in archival material can be performed using the MIB-1 antibody. Unlike our results with p53 and bcl-2, Ki-67 protein expression by immunohistochemistry using MIB-1 was not an independent prognostic marker for cancer recurrence after radical prostatectomy although it may have clinical utility in subsets of patients. Assessment of MIB-1 staining in CaP needle biopsy samples is underway. Tumor neovascularity, or angiogenesis, is necessary for cancers to grow and metastasize. Angiogenesis in CaP as a prognostic marker has received recent attention. Most studies have used factor VIII immunohistochemical staining and increased angiogenesis has been suggested as a staging and prognostic marker. Our group has recently conducted a large study of radical prostatectomy patients and used CD34 antigen immunohistochemistry to assess neovascularity. We did not find that this biomarker assessment was an independent prognostic marker of cancer recurrence after radical prostatectomy. Further work is being conducted in needle biopsy samples. More research is needed to assess new biomarkers and, most importantly, to standardize the methodology for sampling and assaying biomarkers in heterogeneous and multifocal prostate cancer.
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PMID:Angiogenesis, p53, bcl-2 and Ki-67 in the progression of prostate cancer after radical prostatectomy. 1032 96

Drug resistance is a major problem in patients with small cell lung cancer; in fact, most die of resistant disease, despite an initial response. Several markers of drug resistance have been described in preclinical models, but the mechanism of drug resistance in lung cancer patients remains unknown. The objective of this study was to evaluate the role of the expression of a number of markers of drug resistance, proliferation, and apoptosis in relation to response to chemotherapy and survival in patients with small cell lung cancer. Tumor samples were derived from 93 previously untreated patients who were randomized in a Phase III study to receive cyclophosphamide, epirubicine, and etoposide or cyclophosphamide, epirubicine and vincristine alternating with carboplatin and etoposide. Paraffin-embedded samples, derived from the primary tumor site prior to chemotherapy, were analyzed by immunohistochemistry for expression of markers implicated in drug resistance [topoisomerase (topo) IIalpha, topo IIbeta, and multidrug resistance-associated protein], apoptosis (p53, p21, and bcl-2), or proliferation (Ki67). Response prediction was analyzed by chi2 test and logistic regression analysis; overall and disease-free survival curves were compared by log-rank test and Cox regression analysis. Shorter survival was observed in patients with extensive disease (P = 0.037) and poorer performance status (P = 0.028) and in patients whose tumors expressed high topo IIalpha levels (P = 0.01) and high Ki67 (P = 0.024). By multivariate analysis, the following factors were found to be predictive for worse survival: high expression levels of topo IIalpha, Ki67, and bcl-2; male sex; and extensive disease. High topo IIbeta expression was found to be predictive for lower overall and complete response rate. No relationship between apoptotic pathway markers or MRP and response to chemotherapy was observed. In conclusion, high expression of topo IIalpha was predictive of worse survival, and high expression of topo IIbeta was predictive of lower response rates. Furthermore, lower survival probability was observed in patients with bcl-2-positive tumors. Immunohistochemical assessment of these markers in diagnostic biopsies may give important prognostic information and may help selecting patients in the worse prognostic categories for new therapeutic strategies.
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PMID:Expression of DNA topoisomerase IIalpha and topoisomerase IIbeta genes predicts survival and response to chemotherapy in patients with small cell lung cancer. 1047 85

On the basis of a retrospective study of 327 patients with Hodgkin's disease (HD), the prognostic significance of several factors, accepted previously and recently proposed, has been analyzed with regard to response to treatment and the survival time. Multivariate regression analysis strongly decreased the number of potentially prognostic parameters. The only independent, pretreatment factors negatively influenced by either time of survival or response to treatment were the following: age at diagnosis of more than 45 years, advanced (IIIB/IV) clinical stage, poor clinical status according to Karnofsky's scale (score less than 70), presence of systemic symptoms, mixed cellularity/lymphocyte depletion histological type, multisite peripheral nodal localization of the disease, abdominal lymphadenopathy, and large primary tumor mass (bulky disease). Short time to achieve complete remission (during the first four courses of chemotherapy) has proven to be significantly positive predictive factor. Cumulative dose of cytostatics lower than programmed was a significantly negative prognostic factor that correlated with a shorter time of survival. Lack of or a too-low dose of radiotherapy had the same predictive value. High activity of serum lactate dehydrogenase correlated moderately with poor response to the first-line treatment but did not influence the survival time. Other clinical, morphological, and biochemical parameters influenced neither the prognosis nor the response to treatment. Additionally, immunohistochemical examinations for proliferating cell nuclear antigen and the protein products of the p53 and bcl-2 genes were performed on the lymph nodes obtained from the patients with HD. High expression of proliferating cell nuclear antigen, p53, and BCL-2 correlated with poor response to the treatment and/or short time of survival. Statistical analysis has led us to the conclusion that the pretreatment expression of these oncoproteins can be taken into consideration as a new prognostic factor in HD.
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PMID:Prognostic factors in Hodgkin's disease: multivariate analysis of 327 patients from a single institution. 1074 46

We report an aggressively behaving malignant trichogenic tumor arising in a trichoblastoma (TB) with widespread lymphatic and hematogenous metastases in a 55-year-old man with a concomitant B-cell chronic lymphocytic leukemia. The primary tumor had been present and unchanged for as long as 40 years before excision. Typical trichogenic TB with dystrophic calcification and even ossification was still present peripheral to the malignant transformation. The malignant neoplasm consisted of basaloid cells, spindle cells arranged in fascicles and densely packed rounded nests or "cell balls." The metastases consisted of immature basaloid cells and cell balls, and the recurrences became successively more undifferentiated. The residual TB reacted with antibodies to cytokeratin (CK) 6, 8, 14, and 17 and focally to S-100; the malignant primary tumor reacted uniformly with antibodies to vimentin and only focally with antibodies to CK and S-100. The metastatic tumor had lost epidermal CK expression but maintained expression of S-100 in paraffin-embedded tissues. Trichoblastic differentiation was confirmed in frozen tissues with antibodies to hair keratins. No expression of p53 or bcl-2 was identified, but p-glycoprotein (MDR-1 gene related) was expressed by primary and metastatic tumor cells. We believe that this neoplasm is best classified as a trichoblastic carcinoma arising in a TB in association with a B-cell chronic lymphocytic leukemia. This case illustrates that TBs have the potential for malignant transformation and aggressive behavior.
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PMID:Trichoblastic carcinoma ("malignant trichoblastoma") with lymphatic and hematogenous metastases. 1087 73

Tamoxifen is one of the most effective treatments for breast cancer. Standard practice is to select patients who are likely to respond to this therapy through the evaluation of estrogen receptor (ER) and progesterone receptor (PR) in the primary tumor tissue. Over the past 25 yr that physicians have been using ER determination to guide tamoxifen use, numerous studies have demonstrated that this molecular marker is useful in predicting benefit from tamoxifen. ER has been analyzed for many years using ligand-binding assays. However, current practice involves the use of immunohistochemical-based assays to detect ERalpha Immunohistochemistry (IHC) has several advantages. For example, IHC evaluates tumor cell heterogeneity, can be used to study small samples, is less expensive, and allows direct correlation with multiple histopathological tumor features and other molecular markers. PR, an estrogen-responsive protein, can also be useful in predicting response to tamoxifen in specific clinical situations. In recent years, several other markers of tamoxifen response have been examined, including: pS2 (another estrogen-regulated protein), heat-shock proteins 27 and 70, bcl-2 protein, c-erbB-2 (HER-2/neu) oncoprotein, and mutated p53 tumor suppressor protein. In this article, we present an analysis of the data on these new molecular markers. Overall, from numerous studies, the data indicate that in addition to ERalpha bcl-2 is a potential candidate to help further improve our ability to predict response to tamoxifen. ER and bcl-2 are the most useful molecular markers to better identify breast cancer patients who will respond to tamoxifen and who will have prolonged survival.
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PMID:Molecular markers for predicting response to tamoxifen in breast cancer patients. 1105 Oct 41


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