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ABSTRACT: Cancer biomarker studies using the combination of tissue microarray and automated quantitative assessment of immunofluorescence (TMA-AQUA) have been successfully performed for various types of human carcinoma, but its performance characteristics have yet to be evaluated in human lymphoma.
A pilot TMA was constructed containing duplicate 1.5 mm cores from 15 cases of mantle cell lymphoma (MCL), 3 cases of low-grade B-cell lymphoma, and 3 cases of benign lymphoid tissue. Protein expression of c-Myc, Cdc2, Cyclin D1, Ki-67, Mcm2, and p27 by immunofluorescence and chromagenic staining were evaluated by AQUA and visual scoring, respectively. Gene expression of cMYC, CDC2, and CCND1 was determined by quantitative nuclease protection assay.
Protein expression between duplicate cores determined by AQUA showed excellent correlation for all markers [correlation coefficient (R)=0.79 to 0.94] and Cyclin D1 expression was significantly higher in MCL cases compared with non-MCL cases (P=0.00019). Overall correlation of AQUA with scoring of chromagenic staining by 2 pathologists was good for all markers (R=0.56 to 0.90), except Cdc2 (R=0.25). Localization of expression to cytoplasmic and/or nuclear compartments was comparable with chromagenic staining patterns for all markers except Ki-67 and Mcm2, where a significant difference between nuclear and cytoplasmic expression could not be appreciated by AQUA, despite clear nuclear localization by chromagenic staining. Correlation of gene expression with protein expression was variable for CDC2, cMYC, and CCND1 (R=0.32, 0.35, and 0.69).
TMA-AQUA has the potential to be successfully used as a high-throughput protein biomarker screening platform for MCL; however, appropriate target protein selection and antibody performance validation are factors that need to be considered.
Applied immunohistochemistry & molecular morphology: AIMM / official publication of the Society for Applied Immunohistochemistry 09/2010; 19(1):62-9. · 1.63 Impact Factor
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Stephanie Markovina,
Natalie S Callander,
Shelby L O'Connor,
Guangwu Xu,
Yufang Shi, Catherine P Leith,
KyungMann Kim,
Parul Trivedi,
Jaehyup Kim,
Peiman Hematti,
Shigeki Miyamoto
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ABSTRACT: Components of the microenvironment such as bone marrow stromal cells (BMSCs) are well known to support multiple myeloma (MM) disease progression and resistance to chemotherapy including the proteasome inhibitor bortezomib. However, functional distinctions between BMSCs in MM patients and those in disease-free marrow are not completely understood. We and other investigators have recently reported that NF-kappaB activity in primary MM cells is largely resistant to the proteasome inhibitor bortezomib, and that further enhancement of NF-kappaB by BMSCs is similarly resistant to bortezomib and may mediate resistance to this therapy. The mediating factor(s) of this bortezomib-resistant NF-kappaB activity is induced by BMSCs is not currently understood.
Here we report that BMSCs specifically derived from MM patients are capable of further activating bortezomib-resistant NF-kappaB activity in MM cells. This induced activity is mediated by soluble proteinaceous factors secreted by MM BMSCs. Among the multiple factors evaluated, interleukin-8 was secreted by BMSCs from MM patients at significantly higher levels compared to those from non-MM sources, and we found that IL-8 contributes to BMSC-induced NF-kappaB activity.
BMSCs from MM patients uniquely enhance constitutive NF-kappaB activity in MM cells via a proteinaceous secreted factor in part in conjunction with IL-8. Since NF-kappaB is known to potentiate MM cell survival and confer resistance to drugs including bortezomib, further identification of the NF-kappaB activating factors produced specifically by MM-derived BMSCs may provide a novel biomarker and/or drug target for the treatment of this commonly fatal disease.
Molecular Cancer 01/2010; 9:176. · 3.99 Impact Factor
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ABSTRACT: Bortezomib (Velcade/PS341), a proteasome inhibitor used in the treatment of multiple myeloma (MM), can inhibit activation of nuclear factor-kappaB (NF-kappaB), a family of transcription factors often deregulated and constitutively activated in primary MM cells. NF-kappaB can be activated via several distinct mechanisms, including the proteasome inhibitor-resistant (PIR) pathway. It remains unknown what fraction of primary MM cells harbor constitutive NF-kappaB activity maintained by proteasome-dependent mechanisms. Here, we report an unexpected finding that constitutive NF-kappaB activity in 10 of 14 primary MM samples analyzed is refractory to inhibition by bortezomib. Moreover, when MM cells were cocultured with MM patient-derived bone marrow stromal cells (BMSC), microenvironment components critical for MM growth and survival, further increases in NF-kappaB activity were observed that were also refractory to bortezomib. Similarly, MM-BMSCs caused PIR NF-kappaB activation in the RPMI8226 MM cell line, leading to increased NF-kappaB-dependent transcription and resistance to bortezomib-induced apoptosis. Our findings show that primary MM cells frequently harbor PIR NF-kappaB activity that is further enhanced by the presence of patient-derived BMSCs. They also suggest that this activity is likely relevant to the drug resistance development in some patients. Further elucidation of the mechanism of PIR NF-kappaB regulation could lead to the identification of novel diagnostic biomarkers and/or therapeutic targets for MM treatment.
Molecular Cancer Research 09/2008; 6(8):1356-64. · 4.29 Impact Factor
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ABSTRACT: Protein kinase C (PKC)-epsilon, a Ca(2+)-independent, phospholipid-dependent serine/threonine kinase, is among the PKC isoforms expressed in mouse epidermis. We reported that FVB/N transgenic mouse lines that overexpress (8- or 18-fold) PKC-epsilon protein in basal epidermal cells and cells of the hair follicle develop papilloma-independent squamous cell carcinoma (SCC) elicited by 7,12-dimethylbenz(a)anthracene initiation and 12-O-tetradecanoylphorbol-13-acetate-promotion or by repeated ultraviolet radiation exposures. The susceptibility to the development of SCC was proportional to the level of expression of the PKC-epsilon transgene. We now report that PKC-epsilon FVB/N transgenic mice (line 215) that overexpress in epidermis approximately 18-fold PKC-epsilon protein more than their wild-type littermates spontaneously develop a myeloproliferative-like disease (MPD) in 100% of PKC-epsilon transgenic mice. The MPD was characterized by an excess of neutrophils and eosinophils, resulting in invasion of almost all vital organs of the mouse by 6 months of age. On gross examination these mice present with splenomegaly, hepatomegaly, and severe lymphadenopathy. Examination of the bone marrow revealed almost complete effacement by neutrophils, eosinophils, and their precursors. Furthermore, the spleen and lymph nodes were enlarged and exhibited marked extramedullary hematopoiesis. Complete pathological analysis of the second PKC-epsilon transgenic mouse (line 224) that expresses approximately eightfold PKC-epsilon protein more than their wild-type littermates revealed no remarkable findings in any of the affected organs as seen in line 215. However, peripheral blood analyses of PKC-epsilon transgenic mice indicated significant increases of neutrophils in the circulating blood in both PKC-epsilon transgenic lines. To determine whether there was an imbalance of cytokines in PKC-epsilon transgenic mice (line 215), resulting in aberrant myelopoiesis, we analyzed 17 cytokines in the peripheral blood. This analysis indicated that interleukin-5, interleukin-6, and granulocyte-colony stimulating factor were up-regulated as a function of age. The transgene PKC-epsilon was not detected in any of the affected organs (bone marrow, liver, spleen, lung) We suggest that overexpression of PKC-epsilon in the epidermis may lead to the induction of specific cytokines that may, in a paracrine mechanism, perturb normal hematopoiesis in bone marrow resulting in a granulocytic skew toward that of neutrophils and eosinophils. The susceptibility of PKC-epsilon transgenic mice to the induction of SCC and the spontaneous development of MPD are unrelated.
American Journal Of Pathology 02/2005; 166(1):117-26. · 4.89 Impact Factor