| 1. |
- Stanezai, S., et al.
(författare)
-
Higher intensity of Low Molecular Weight Protein Tyrosine Phosphatase/ ACP-1 in survivors of patients diagnosed with Diffuse Large B Cell Lymphoma (DLBCL) compared to non-survivors
- 2016
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Ingår i: Austin Biology. - : Austin Publishing. ; 1:2
-
Tidskriftsartikel (refereegranskat)abstract
- Adult Diffuse Large B Cell Lymphoma (DLBCL) is a heterogeneous form of hematopoietic cancer and difficult to treat. In order to find a better diagnostic indication for the disease, we analyzed Low Molecular Weight Protein Tyrosine Phosphatase (LMWPTP) that in humans is encoded by the ACP1 gene. LMWPTP is an enzyme shown to counteract Protein Tyrosine Kinases (PTK) and was suggested to be a negative growth factor regulator. However, the 18 kDa PTP can also have a positive effect on cell growth and proliferation, indicating a controversial role in the tumorigenic process. LMWPTP exists in different isoforms which are electrophoretically, kinetically and immunologically distinct. We have studied two subgroups of DLBCL consisting of a Germinal Center B cell like (GCB) and a non-Germinal Center B cell like (non-GCB) group. The two subgroups have been defined by gene-expressing profiling and are associated with differential outcome. The expression levels of LMWPTP protein was compared and showed significant differences between the GCB and non- GCB subgroups (p=0.012). Interestingly, when the samples were divided into survivors and non-survivors, and thereafter analyzed for LMWPTP expression, the samples from patients with a higher survival rate showed increased staining intensity, whereas the samples from patients with lower intensity of LMWPTP did not survive the disease (p=0.001). In conclusion, we have shown that DLBCL patients with worse outcome express LMWPTP with a lower intensity, suggesting a tumor suppressor role for this form of the enzyme.
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| 2. |
- Ekberg, Jenny, et al.
(författare)
-
Expression of cyclin A1 and cell cycle proteins in hematopoietic cells and acute myeloid leukemia and links to patient outcome
- 2005
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Ingår i: European Journal of Haematology. - : Wiley-Blackwell Publishing Inc.. - 0902-4441 .- 1600-0609. ; 75:2, s. 106-115
-
Tidskriftsartikel (refereegranskat)abstract
- Abnormal expression of several key regulators essential for G1/S transitions has been implicated in tumorigenesis. A critical role of cyclin A1 in the development of acute myeloid leukemia (AML) has previously been demonstrated in transgenic mice. Our present study focused on the expression and prognostic significance of cyclin A1 and a panel of cell cycle regulatory proteins including cyclin A2, cyclin B1, cyclin E, CDK1, CDK2, p21 and p27 in bone marrow samples from 40 patients with AML. Freshly isolated CD34+ hematopoietic cells and bone marrow samples from 10 healthy donors were also assessed for cell type- and subcellular-specific expression of the cell cycle regulatory proteins. The level of cyclin A1 expression was the only factor that showed a significant correlation with patient outcome. In log-rank test stratified by levels of cyclin A1 expression, patients with high levels of cyclin A1 had significantly worse overall survival (OS) (P = 0.012) compared to those with low levels. Further, patients with high levels of cyclin A1 had significantly lower disease-free survival (DFS) (P = 0.028). Multivariate analysis indicated that cyclin A1 protein expression was an independent prognostic factor for predicting DFS (P = 0.035) and OS (P = 0.045). No correlation between cyclin A1 expression and age was found. However, expression of cyclin A2, cyclin B1, cyclin E, CDK1, CDK2, p21 and p27 did not show prognostic significance in these AML patients.
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| 3. |
- Fridberg, Marie, et al.
(författare)
-
Immunohistochemical analyses of phosphatases in childhood B-cell lymphoma : lower expression of PTEN and HePTP and higher number of positive cells for nuclear SHP2 in B-cell lymphoma cases compared to controls
- 2008
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Ingår i: Pediatric Hematology & Oncology. - : Taylor & Francis. - 0888-0018 .- 1521-0669. ; 25, s. 528-540
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Tidskriftsartikel (refereegranskat)abstract
- Although many pediatric B-cell lymphoma patients are being cured today, much is still unknown about the pathogenesis of this disease. Protein tyrosine phosphatases are involved in the control of survival, growth, and differentiation of cells. The authors have analyzed 26 pediatric B-cell lymphoma cases for the expression of a panel of phosphatases and report a statistically significant lower expression intensity of PTEN and HePTP and higher nuclear SHP2 expression in B-cell lymphoma cases compared to lymphoid tissue. Knowledge about the expression of key regulatory proteins in pediatric B-cell lymphomas is necessary for revealing the complex molecular background of this disease.
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| 4. |
- Fridberg, Marie, et al.
(författare)
-
Protein expression and cellular localization in two prognostic subgroups of diffuse large B-cell lymphoma : higher expression of ZAP70 and PKC-beta II in the non-germinal center group and poor survival in patients deficient in nuclear PTEN
- 2007
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Ingår i: Leukemia and Lymphoma. - : Informa UK Limited. - 1042-8194 .- 1029-2403. ; 48:11, s. 2221-2232
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Tidskriftsartikel (refereegranskat)abstract
- Patients diagnosed with diffuse large B-cell lymphoma (DLBCL) show varying responses to conventional therapy, and this might be contributed to the differentiation stage of the tumor B-cells. The aim of the current study was to evaluate a panel of kinases (ZAP70, PKC-β I and II and phosphorylated PKB/Akt) and phosphatases (PTEN, SHP1 and SHP2) known to be frequently deregulated in lymphoid malignancies. De novo DLBCL cases were divided into two subgroups, the germinal center (GC) group (14/28) and the non-germinal center (non-GC) or activated B-cell (ABC) group (14/28). ZAP70 and PKC-β II were expressed in a significantly higher percentage of tumor cells in the clinically more aggressive non-GC group compared with the prognostically favourable GC group. Also, the subcellular localization of PKC-β I and II differed in DLBCL cells, with the PKC-β I isoform being expressed in both the cytoplasm and nucleus, while PKC-β II was found exclusively in the cytoplasm. Loss of nuclear PTEN correlated with poor survival in cases from both subgroups. In addition, five cell lines of DLBCL origin were analyzed for protein expression and for mRNA levels of PTEN and SHP1. For the first time, we show that ZAP70 is expressed in a higher percentage of tumor cells in the aggressive non-GC subgroup of DLBCL and that PKC-β I and II are differently distributed in the two prognostic subgroups of de novo DLBCL.
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| 5. |
- Hedblom, Andreas, et al.
(författare)
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CDK1 interacts with RARγ and plays an important role in treatment response of acute myeloid leukemia
- 2013
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Ingår i: Cell Cycle. - : Taylor & Francis. - 1538-4101 .- 1551-4005. ; 12:8, s. 1251-1266
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Tidskriftsartikel (refereegranskat)abstract
- Alterations in cell cycle pathways and retinoic acid signaling are implicated in leukemogenesis. However, little is known about the roles of cyclin-dependent kinases (CDKs) in treatment response of leukemia. In this study, we observed that CDK1 expression was significantly higher in bone marrow from 42 patients with acute myeloid leukemia (AML) at recurrence than that at first diagnosis (p = 0.04). AML patients had higher level of nuclear CDK1 in their leukemic blasts tended to have poorer clinical outcome compared with those with lower levels. We showed that CDK1 function is required for all-trans retinoic acid (ATRA) to achieve the optimal effect in U-937 human leukemic cells. CDK1 modulates the levels of P27(kip) and AKT phosphorylation in response to ATRA treatment. Further, we show, for the first time, that RARγ in concert with ATRA regulates protein levels of CDK1 and its subcellular localization. The regulation of the subcellular content of CDK1 and RARγ by ATRA is an important process for achieving an effective response in treatment of leukemia. RARγ and CDK1 form a reciprocal regulatory circuit in the nucleus and influence the function and protein stability of each other and the level of P27(kip) protein. In addition, expression of wee1 kinase and Cdc25A/C phosphatases also coincide with CDK1 expression and its subcellular localization in response to ATRA treatment. Our study reveals a novel mechanism by which CDK1 and RARγ coordinate with ATRA to influence cell cycle progression and cellular differentiation.
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| 6. |
- Holm, Caroline, et al.
(författare)
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Cyclin A1 expression and associations with disease characteristics in childhood acute lymphoblastic leukemia
- 2006
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Ingår i: Leukemia research. - : Elsevier. - 0145-2126 .- 1873-5835. ; 30:3, s. 254-261
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Tidskriftsartikel (refereegranskat)abstract
- A critical cell cycle regulatory protein, cyclin A1, has been implicated in the development of acute myeloid leukemia (AML). Here, we have examined the expression and clinical significance of cyclin A1 in childhood acute lymphoblastic leukemia (ALL). Cyclin A1 was highly expressed in lymphoblastic leukemic cell lines and in 22 of 30 ALL patients (73%). Cyclin A1 expression correlated with patient age (P=0.006), but not with cytogenetic abnormalities. Patients with high levels of cyclin A1 had poorer event-free survival (57.9%) compared to patients with lower levels (75%).
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| 7. |
- Kopparapu, Pradeep Kumar, et al.
(författare)
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Expression and localization of serotonin receptors in human breast cancer
- 2013
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Ingår i: Anticancer Research. - : International Institute of Anticancer Research. - 0250-7005 .- 1791-7530. ; 33:2, s. 363-370
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to examine the expression of serotonin receptors in patients with breast cancer and to explore their utility as diagnostic and prognostic markers. Immunohistochemical analysis was performed to examine the expression of serotonin (5-HT) receptor subtypes 1A, 1B, 2B and 4 in a tissue microarray containing tumor specimens from 102 patients. Statistical analysis was performed to correlate the expression of these proteins with regard to clinical parameters. We found that all four serotonin receptors (5-HTRs) exhibited different expression patterns in breast cancer specimens. In general strong staining for 5-HTR1A was observed on the membrane of cancer cells but it was detected only in the cytoplasm of non-malignant cells. 5-HTR1B and 5-HTR2B were predominantly expressed in the cytoplasm of breast cancer cells, while 5-HTR4 was exclusively found in the nucleus of malignant and non-malignant cells. Correlation analysis revealed a significant correlation of 5-HTR2B with estrogen receptor-α (ER-α) and 5-HTR4 with ER-α and progesterone (PR). In conclusion, the different expression patterns and subcellular localization of 5-HTRs in breast cancer may reflect their role in breast cancer progression.
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| 8. |
- Stanezai, Sanga, et al.
(författare)
-
Higher intensity of low molecular weight protein tyrosine phosphatase/ ACP-1 in survivors of patients diagnosed with diffuse large B cell lymphoma (DLBCL) compared to non-survivors
- 2016
-
Ingår i: Austin Biology. - : Austin Publishing. ; 1:2:2
-
Tidskriftsartikel (refereegranskat)abstract
- Adult diffuse large B cell lymphoma (DLBCL) is a heterogeneous form of hematopoietic cancer and difficult to treat. In order to find a better diagnostic indication for the disease, we analyzed low molecular weight protein tyrosine phosphatase (LMWPTP) that in humans is encoded by the ACP1 gene. LMWPTP is an enzyme shown to counteract protein tyrosine kinases (PTK) and was suggested to be a negative growth factor regulator. However, the 18 kDa PTP can also have a positive effect on cell growth and proliferation, indicating a controversial role in the tumorigenic process. LMWPTP exists in different isoforms which are electrophoretically, kinetically and immunologically distinct. We have studied two subgroups of DLBCL consisting of a germinal center B cell like (GCB) and a non-germinal center B cell like (non-GCB) group. The two subgroups have been defined by gene-expressing profiling and are associated with differential outcome. The expression levels of LMWPTP protein was compared and showed significant differences between the GCB and non-GCB subgroups (p=0.012). Interestingly, when the samples were divided into survivors and non-survivors, and thereafter analyzed for LMWPTP expression, the samples from patients with a higher survival rate showed increased staining intensity, whereas the samples from patients with lower intensity of LMWPTP did not survive the disease (p=0.001). In conclusion, we have shown that DLBCL patients with worse outcome express LMWPTP with a lower intensity, suggesting a tumor suppressor role for this form of the enzyme.
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| 9. |
- Syed Khaja, Azharuddin Sajid, et al.
(författare)
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Cyclin A1 modulates the expression of vascular endothelial growth factor and promotes hormone-dependent growth and angiogenesis of breast cancer.
- 2013
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:8
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Tidskriftsartikel (refereegranskat)abstract
- Alterations in cellular pathways related to both endocrine and vascular endothelial growth factors (VEGF) may contribute to breast cancer progression. Inhibition of the elevated levels of these pathways is associated with clinical benefits. However, molecular mechanisms by which endocrine-related pathways and VEGF signalling cooperatively promote breast cancer progression remain poorly understood. In the present study, we show that the A-type cyclin, cyclin A1, known for its important role in the initiation of leukemia and prostate cancer metastasis, is highly expressed in primary breast cancer specimens and metastatic lesions, in contrasting to its barely detectable expression in normal human breast tissues. There is a statistically significant correlation between cyclin A1 and VEGF expression in breast cancer specimens from two patient cohorts (p<0.01). Induction of cyclin A1 overexpression in breast cancer cell line MCF-7 results in an enhanced invasiveness and a concomitant increase in VEGF expression. In addition, there is a formation of protein-protein complexes between cyclin A1 and estrogen receptor ER-α cyclin A1 overexpression increases ER-α expression in MCF-7 and T47D cells. In mouse tumor xenograft models in which mice were implanted with MCF-7 cells that overexpressed cyclin A1 or control vector, cyclin A1 overexpression results in an increase in tumor growth and angiogenesis, which is coincident with an enhanced expression of VEGF, VEGFR1 and ER-α Our findings unravel a novel role for cyclin A1 in growth and progression of breast cancer, and suggest that multiple cellular pathways, including cell cycle regulators, angiogenesis and estrogen receptor signalling, may cooperatively contribute to breast cancer progression.
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