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Byline: Hyunsoo Kim, Jeff X. Zhou, Herbert C. Morse III, Haesun Park The identification of discriminative genes for categorical phenotypes in microarray gene expression data analysis has been extensively studied, especially for disease diagnosis. In recent biological experiments, continuous phenotypes have also been dealt with. For example, the extent of programmed cell death (apoptosis) can be measured by the level of caspase 3 enzyme. Thus, an effective gene selection method for continuous phenotypes is desirable. In this paper, we describe a three-stage framework for gene expression data analysis based on L1-norm support vector regression (L1-SVR). The first stage ranks genes by recursive multiple feature elimination based on L1-SVR. In the second stage, the minimal genes are determined by a kernel regression, which yields the lowest ten-fold cross-validation error. In the last stage, the final non-linear regression model is built with the minimal genes and optimal parameters found by leave-one-out cross-validation. The experimental results show a significant improvement over the current state-of-the-art approach, i.e., the two-stage process, which consists of the gene selection based on L1-SVR and the third stage of the proposed method.

INHBA (inhibin βA), a subunit of a ligand of the transforming growth factor-β superfamily, is known to play diverse roles in various solid tumors. However, its role in hematologic malignancies remains unexplored. Here, we investigated the function of INHBA in diffuse large B-cell lymphoma (DLBCL). Both mRNA and protein levels of INHBA were significantly downregulated in primary DLBCL tissues, irrespective of germinal center B-cell-like (GCB) or non-GCB subtype, compared to those in benign tonsils. The low level of INHBA in patients with de novo DLBCL was correlated with reduced overall and progression-free survival. Ectopic expression of INHBA in DLBCL cell lines (OCI-Ly01 and SUDHL-10) resulted in reduced cell proliferation, increased spontaneous apoptosis and arrested cell cycle in vitro and suppressed xenograft tumor growth in vivo. Moreover, INHBA enhanced the chemosensitivity of DLBCL cells. Thus, our results provide novel evidence that INHBA functions as a tumor suppressor in DLBCL. [ABSTRACT FROM AUTHOR]

Inhibin-β A (INHBA) is a ligand of the transforming growth factor β superfamily and associated with tumorigenesis and tumor progression in solid tumors. In this study, we investigated the expression levels and clinical significance ofINHBAin acute myeloid leukemia (AML). The results showed that high expression ofINHBAwas significantly correlated with elderly age (>60 years) (p = .038), adverse cytogenetic risks (p = .034), negativeNPM1mutation (p = .016), positiveFLT3internal tandem duplications (p = .011), and low hemoglobin levels (<60 g/dL) (p = .04). Patients with high levels ofINHBAhad poor responses to therapies as indicated by lower complete remission rate (p = .004), higher early death rate (p = .018), and shorter relapse-free survival (p = .04) and overall survival (p = .003). Moreover, multivariate analysis showed that high expression ofINHBAwas an independent adverse prognostic factor for AML. Taken together, our study suggested that high expression ofINHBAwas an adverse prognostic factor forde novoAML. [ABSTRACT FROM AUTHOR]

Background: Peritoneum metastasis of lung cancer is a rare event which, in addition to the peritoneum, usually involves multiple metastatic tissues. Here we report a case of a patient with lung adenosquamous cell carcinoma with the peritoneum as the sole distant metastatic site.Case Presentation: An 82-year-old Han Chinese man, in the teaching profession, was diagnosed with lung adenosquamous cell carcinoma in the upper lobe of his left lung with the involvement of ipsilateral hilar and mediastinal lymph nodes, and was initially staged as IIIa (cT2N2M0). Molecular testing identified a mutation at KRAS G12A. Due to his poor physical condition, our patient was given gamma knife radiotherapy with a total dose of 28.0 Gy. Two weeks later, our patient was diagnosed as peritoneal metastasis identified by using magnetic resonance imaging and confirmed with ascitic cytology and peritoneal histology. No other distant metastatic sites such as liver, brain, bone, paranephroi, and lungs were found. Subsequently, our patient received palliative intraperitoneal chemotherapy, and died within 2 months.Conclusions: Our patient represented a rare case of lung adenosquamous cell carcinoma harboring the KRAS G12A mutation, which metastasized distantly to the peritoneum only, and progressed rapidly. [ABSTRACT FROM AUTHOR]

Reactions of copper salts, zoledronic acid, and 2,2′-bipyridine/1,10-phenanthroline in aqueous ethanolic solutions afforded four phosphonate oxygen-bridged copper complexes, Cu(bipy)(H4zdn)(HSO4) (1), [Cu2(bipy)2(H2zdn)(H2O)(Cl)]·4H2O (2), [Cu2(phen)2(H2zdn)(H2O)(Cl)]·2.5H2O (3), and [Cu3(bipy)3(H4zdn)(H2zdn)(SO4)]·5H2O (4) (H5zdn = zoledronic acid, bipy = 2,2′-bipyridine, phen = 1,10-phenanthroline). The copper centers of1–4have square pyramidal coordination geometries. The Cu(II) ions are coordinated to bipy/phen, zoledronate, and HSO4−/Cl−forming mononuclear units for1, dinuclear for2and3, and trinuclear for4. These building units are further extended into 3-D supramolecular networks via multiple hydrogen bond interactions. Temperature-dependent magnetic properties of2and4suggest weak antiferromagnetic coupling (J = −4.53(8) cm−1for2,J = −1.69(4) cm−1for4). The antitumor activity of2was evaluated against the human lung cancer cell line and indicates effective time- and dose-dependent cytotoxic effects. [ABSTRACT FROM PUBLISHER]

Anaplastic lymphoma kinase (ALK) gene fusion is a driving mutation underlying the development of non-small cell lung cancer (NSCLC). Accurate detection of ALK fusion is critical for the use of ALK inhibitors in the treatment of NSCLC. Commonly utilized methods for ALK detection include fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). However, these methods are time-consuming and costly. In the present study, a method for assessing ALK gene fusion based on the differential expression levels of the ALK kinase and non-kinase domains was developed and evaluated, with the aim of providing a convenient and reliable method for the detection of ALK fusion. In addition, another method was established to determine the integrity of exons 19-20 and 20-21 of ALK, two genomic loci that are typically broken in ALK fusions. These novel methods were applied to detect ALK fusion in 100 NSCLC patients, and were compared with IHC and FISH methods. The novel methods developed in the present study successfully detected ALK fusions in 10 samples. The concordances between the novel methods and IHC and FISH were 100%. Furthermore, the differential expression method was able to detect ALK fusions in cell-free urine samples, which was advantageous over FISH and IHC. The novel methods developed in the present study are cost-effective and easy to perform, and may provide simple and convenient techniques for the clinical assessment of ALK fusions, facilitating the use of targeted therapy for NSCLC. [ABSTRACT FROM AUTHOR]

Interferon (IFN) consensus sequence-binding protein/IFN regulatory factor 8 (IRF8) is a transcription factor that regulates the differentiation and function of macrophages, granulocytes, and dendritic cells through activation or repression of target genes. Although IRF8 is also expressed in lymphocytes, its roles in B cell and T cell maturation or function are ill defined, and few transcriptional targets are known. Gene expression profiling of human tonsillar B cells and mouse B cell lymphomas showed that IRF8 transcripts were expressed at highest levels in centroblasts. either from secondary lymphoid tissue or transformed cells. In addition, staining for IRF8 was most intense in tonsillar germinal center (GC) dark-zone centroblasts. To discover B cell genes regulated by IRF8. we transfected purified primary tonsillar B cells with enhanced green fluorescent protein-tagged IRF8, generated small interfering RNA knockdowns of IRF8 expression in a mouse B cell lymphoma cell line, and examined the effects of a null mutation of IRF8 on B cells. Each approach identified activation-induced cytidine deaminase (AICDA] and BCL6 as targets of transcriptional activation. Chromatin immunoprecipitation studies demonstrated in vivo occupancy of 5′ sequences of both genes by IRF8 protein. These results suggest previously unappreciated roles for IRF8 in the transcriptional regulation of B cell GC reactions that include direct regulation of AICDA and BCL6. [ABSTRACT FROM AUTHOR]

Abstract: Mesenchymal stem cells (MSCs) are the first type of stem cells to be utilized in clinical regenerative medicine, mainly owing to their capacity for multipotent differentiation and the feasibility of autologous transplantation. More recently, the specific tumor-oriented migration and incorporation of MSCs have been demonstrated in various pre-clinical models, highlighting the potential for MSCs to be used as an ideal carrier for anticancer gene delivery. Engineered with specific anticancer genes, MSCs possess the ability of dual-targeting tumor cells. This contrasts with non-engineered native MSCs which have intrinsic pro- and anti-tumorigenic properties. Engineered MSCs are capable of producing specific anticancer agents locally and constantly. Astute investigation on engineered MSCs may lead to a new avenue toward an efficient therapy for patients with cancer. [Copyright &y& Elsevier]

INHBA (inhibin βA), a subunit of a ligand of the transforming growth factor-β superfamily, is known to play diverse roles in various solid tumors. However, its role in hematologic malignancies remains unexplored. Here, we investigated the function of INHBA in diffuse large B-cell lymphoma (DLBCL). Both mRNA and protein levels of INHBA were significantly downregulated in primary DLBCL tissues, irrespective of germinal center B-cell-like (GCB) or non-GCB subtype, compared to those in benign tonsils. The low level of INHBA in patients with de novo DLBCL was correlated with reduced overall and progression-free survival. Ectopic expression of INHBA in DLBCL cell lines (OCI-Ly01 and SUDHL-10) resulted in reduced cell proliferation, increased spontaneous apoptosis and arrested cell cycle in vitro and suppressed xenograft tumor growth in vivo. Moreover, INHBA enhanced the chemosensitivity of DLBCL cells. Thus, our results provide novel evidence that INHBA functions as a tumor suppressor in DLBCL.

Background: Peritoneum metastasis of lung cancer is a rare event which, in addition to the peritoneum, usually involves multiple metastatic tissues. Here we report a case of a patient with lung adenosquamous cell carcinoma with the peritoneum as the sole distant metastatic site., Case Presentation: An 82-year-old Han Chinese man, in the teaching profession, was diagnosed with lung adenosquamous cell carcinoma in the upper lobe of his left lung with the involvement of ipsilateral hilar and mediastinal lymph nodes, and was initially staged as IIIa (cT 2 N 2 M 0 ). Molecular testing identified a mutation at KRAS G12A. Due to his poor physical condition, our patient was given gamma knife radiotherapy with a total dose of 28.0 Gy. Two weeks later, our patient was diagnosed as peritoneal metastasis identified by using magnetic resonance imaging and confirmed with ascitic cytology and peritoneal histology. No other distant metastatic sites such as liver, brain, bone, paranephroi, and lungs were found. Subsequently, our patient received palliative intraperitoneal chemotherapy, and died within 2 months., Conclusions: Our patient represented a rare case of lung adenosquamous cell carcinoma harboring the KRAS G12A mutation, which metastasized distantly to the peritoneum only, and progressed rapidly.

Emerging evidence shows that the aberrantly expressed cyclic AMP responsive element-binding protein (CREB) is associated with tumor development and progression in several cancers. Spindle and kinetochore-associated protein 2 (SKA2) is essential for regulating the progress of mitosis. In this study, we evaluate in vitro and in vivo the functional relationship between CREB and SKA2 in renal cell carcinoma (RCC). Suppressing and replenishing CREB levels were used to manipulate SKA2 expression, observing the effects on RCC cell lines. Computational prediction and ChIP assay identified that CREB targeted ska2 by binding its CRE sequence in the human genome. Overexpression of CREB reversed the inhibited cell growth following siSKA2 treatment, and reduced the number of cells holding in mitosis. Decreased expression of CREB suppressed RCC cell growth and xenograft tumor formation, accompanied by reduced expression of SKA2. In RCC tumor samples from patients, mRNA for SKA2 were plotted near those of CREB in each sample, with significantly increased immunohistochemical staining of higher SKA2 and CREB in the higher TNM stages. The study adds evidence that CREB, a tumor oncogene, promotes RCC proliferation. It probably achieves this by increasing SKA2 expression.

Anaplastic lymphoma kinase (ALK) gene fusion is a driving mutation underlying the development of non-small cell lung cancer (NSCLC). Accurate detection of ALK fusion is critical for the use of ALK inhibitors in the treatment of NSCLC. Commonly utilized methods for ALK detection include fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). However, these methods are time-consuming and costly. In the present study, a method for assessing ALK gene fusion based on the differential expression levels of the ALK kinase and non-kinase domains was developed and evaluated, with the aim of providing a convenient and reliable method for the detection of ALK fusion. In addition, another method was established to determine the integrity of exons 19-20 and 20-21 of ALK, two genomic loci that are typically broken in ALK fusions. These novel methods were applied to detect ALK fusion in 100 NSCLC patients, and were compared with IHC and FISH methods. The novel methods developed in the present study successfully detected ALK fusions in 10 samples. The concordances between the novel methods and IHC and FISH were 100%. Furthermore, the differential expression method was able to detect ALK fusions in cell-free urine samples, which was advantageous over FISH and IHC. The novel methods developed in the present study are cost-effective and easy to perform, and may provide simple and convenient techniques for the clinical assessment of ALK fusions, facilitating the use of targeted therapy for NSCLC.

CD300A is a type I transmembrane receptor protein which has shown inhibitory effects on B-cell receptor-mediated signals. In an analysis of public dataset, we found that CD300A mRNA levels were inversely correlated with the overall survival time of patients with diffuse large B-cell lymphoma (DLBCL). To decipher the role of CD300A in DLBCL, we knocked down the expression levels of CD300A in DLBCL cells and found that decreasing levels of CD300A significantly inhibited cell proliferation of OCI-Ly01, Farage, and SUDHL-4 cells, but not of VAL, OCI-Ly10, or SUDHL-8 cells. Mechanistically, reduced expression of CD300A resulted in a marked attenuation of AKT phosphorylation, a key molecular event in tumorigenesis, in OCI-Ly01, Farage, and SUDHL-4 cells. Pharmacologic inhibition of PI3K displayed a similar inhibitory effect on cell proliferation. Furthermore, using a xenograft animal model, we found that decreasing levels of CD300A in OCI-Ly01 and Farage cells significantly inhibited tumor formation in vivo. Collectively, our results suggested an oncogenic role of CD300A in DLBCL which could serve as a potential biomarker and therapeutic target for this malignant disease.

Animal models are indispensable for the study of tumorigenesis and the development of anti-cancer drugs for human pancreatic cancer. In the present study, two orthotopic xenograft mouse models were developed. AsPC-1 human pancreatic cancer cells were stably labeled with red fluorescent protein (RFP) and injected subcutaneously into nude mice. For the orthotopic tumor mass model, the formed subcutaneous tumors were cut into blocks and implanted into the pancreas of nude mice via laparotomy. For the Matrigel™ tumor block model, solidified Matrigel containing RFP-labeled AsPC-1 cells was cut into blocks and implanted into the pancreas of nude mice. A subcutaneous tumor xenograft model was used as a control. Tumor growth and metastasis were assessed using an in vivo fluorescence imaging system. Thirty-six days after implantation, all mice from the two orthotopic xenograft models (n=20 per group) and 55% of the subcutaneous xenograft mice (n=20) developed tumors. The tumor growth rate was significantly higher in the orthotopic models than that in the subcutaneous model (P<0.01). Metastasis to organs such as the liver was observed in the orthotopic tumor models. Histological examination showed that the tumors were poorly differentiated adenocarcinomas. In conclusion, two orthotopic xenograft mouse models of human pancreatic cancer were established; these exhibited greater tumor growth and metastasis than the subcutaneous xenograft mouse model.

IRF8 is a transcription factor with a critical role in B lymphocyte development and functions. Its role in human diffuse large B-cell lymphoma (DLBCL), however, remained elusive. In this study, using shRNA-mediated knockdown of IRF8 expression, we found that the loss of IRF8 significantly reduced the proliferation of DLBCL cells (P<0.05). Mechanistically, decreasing the levels of IRF8 led to a suppression of the phosphorylation of p38 and ERK, molecules critical for B cell proliferation. Furthermore, using a xenograft lymphoma mouse model, we found that the loss of IRF8 significantly inhibited the growth of lymphomas in vivo (P<0.05). Immunohistochemical analysis of human DLBCL tissues revealed that the levels of IRF8 were significantly greater in non-germinal center B-cell-like (non-GCB) subtype than that in GCB subtype (P<0.05). Analysis of public available data also suggested that the expression levels of IRF8 mRNA in human DLBCL tissues were inversely correlated with patients' overall survival time. Taken together, this study suggested that IRF8 may play an oncogenic role in human DLBCL by promoting cell proliferation.

Our previous studies illustrated that a steady increase of intracellular calcium concentration ([Ca2+]i) was important for maintaining microtubules (MTs) rearrangement in apoptotic cells. However, little is known about the effect of calcium sensing receptor (CaSR)-mediated increase in [Ca2+]i on cytoskeleton gene expression. We examined the impact of taxol or CaSR agonist/antagonist on the regulation of [Ca2+]i concentration, cytoskeleton arrangement, phosphorylated CREB and cytoskeleton gene expressions in HeLa cells with dominant negative plasmid of CREB (PM). This study demonstrated that Gdcl3 (a specific CaSR agonist) evoked a rapid increase of [Ca2+]i, formed a rigid bundle of MTs which surrounded the nucleus and decreased the cytoskeleton gene expressions in HeLa cells. These effects were rescued by addition of NPS2390 (a specific CaSR antagonist). Moreover, CaSR activity affected cytoskeleton gene expression through transcription factor CREB. Histoscores of pCREB immunoreactivity in tissues of cervical adenocarcinoma, renal clear cell carcinoma, and diffuse large B-cell lymphoma were markedly increased compared with non malignant tissue. These data demonstrate, for the first time, that CaSR-mediated increase in [Ca2+]i probably modulate cytoskeleton organization and gene expression via transcription factor., (© 2014 Wiley Periodicals, Inc.)

Background: Excision repair cross complementation group 1 (ERCC1) is a nucleotide excision repair pathway gene which provides protection against platinum-based chemotherapy-induced DNA damage., Methods: ERCC1 mRNA expression was quantified by quantitative real-time reverse-transcription PCR in paraffin-embedded non-small cell lung cancer (NSCLC; n = 357), gastric cancer (n = 106), and breast cancer (n = 363) tissues. Survival curves were generated by Kaplan-Meier analysis; Cox proportional multivariate regression analysis was applied., Results: ERCC1 mRNA expression was significantly higher in breast cancer than gastric cancer or NSCLC (both P < 0.0001), but not significantly different in NSCLC and gastric cancer (P = 0.119). In NSCLC, the low ERCC1 group had significantly longer disease free survival (DFS) than the high ERCC1 group (29.1 vs. 21.0 months, P < 0.0001); in the surgery alone and postoperative platinum-containing chemotherapy subgroups, DFS was significantly longer for the low ERCC1 groups than high ERCC1 groups (30.2 vs. 25.1 months, P = 0.018; 27.0 vs. 19.4 months, P < 0.0001, respectively). In gastric cancer patients receiving surgery alone, the low ERCC1 group had significantly longer overall survival than the high ERCC1 group (47.54 vs. 27.47 months, P = 0.018)., Conclusions: High ERCC1 mRNA expression of the NSCLC tumor tissues was associated with poor disease-free survival (DFS), in both the surgery alone and postoperative platinum-containing chemotherapy subgroups. Meanwhile, low ERCC1 mRNA expression had significantly longer overall survival in gastric cancer patients receiving surgery alone. Therefore, ERCC1 expression was a prognostic factor and predictive marker in NSCLC, and gastric cancer after surgery alone, but was not a prognostic factor in breast cancer.

Mutations of the KRAS, BRAF, and PIK3CA genes have been reported in colorectal cancer (CRC), associated with resistance to epidermal growth factor receptor (EGFR)-targeted monoclonal antibody therapy. These reports have mainly emanated from Western countries, however, and little is known about the mutation frequencies of these genes and their prognostic value in Asian patients with CRC. In this study, we analyzed the mutation frequencies of these three genes together with EGFR, and their association with overall survival in 61 Chinese patients with metastatic CRC (mCRC). Gene mutations were examined using pyrosequencing. Kaplan-Meier survival analysis and multivariate Cox proportional hazard analysis were used to assess the prognostic significance of mutations of these four genes for patients' survival. We found that the mutations of KRAS, BRAF, PIK3CA, and EGFR were present in 12 (19.7%), 3 (4.9%), 3 (4.9%), and 0 patients, respectively. Kaplan-Meier survival analysis showed that none of these gene mutations correlated significantly with patients' overall survival. Multivariate Cox proportional hazard analysis showed only treatment regimens and age to be independent prognostic factors. Our findings indicate that EGFR signaling network genes are frequently mutated in Chinese mCRC patients, and these gene mutations do not seem to be associated with patients' overall survival., (2010. © 2010 Wiley-Liss, Inc.)

IFN regulatory factor 8 (IRF8) is a transcription factor that affects the differentiation and function of myeloid, dendritic, and B cells. Herein we report that IRF8 regulates the expression of Mdm2, a suppressor of p53-dependent and -independent apoptosis pathways, in germinal center (GC) B cells. In GC B cells of IRF8-deficient mice, Mdm2 transcripts were greatly down-regulated, and MDM2 protein was poorly expressed in GC of Irf8(-/-) mice. Small interfering RNA-induced repression of IRF8 in a GC-derived B cell line resulted in decreased expression of MDM2 at the protein level but increased expression of p53 and p21. We found that IRF8 binds to the Mdm2 P2 promoter, and that cotransfection of an IRF8 expression vector with an Mdm2 reporter construct stimulated significant increases in reporter activity. Additionally, transcripts of the p53 target Pmaip1 (Noxa) were significantly increased in IRF8-deficient GC B cells as well as in the IRF8 knockdown B cell line. Finally, cells deficient in IRF8 exhibited growth suppression and increased sensitivity to apoptosis induced by etoposide or IL-21. These results suggest that by regulating MDM2, IRF8 might allow GC B cells to tolerate physiological DNA breaks that otherwise would trigger apoptosis.

We have compared histologic features and gene expression profiles of newly identified plasmacytomas from NFS.V(+) congenic mice with plasmacytomas of IL6 transgenic, Fasl mutant, and SJL-beta2M(-/-) mice. NFS.V(+) tumors comprised an overlapping morphologic spectrum of high-grade/anaplastic, intermediate-grade/plasmablastic, and low-grade/plasmacytic cases with similarities to subsets of human multiple myeloma and plasmacytoma. Microarray and immunohistochemical analyses of genes expressed by the most prevalent tumors, plasmablastic plasmacytomas, showed them to be most closely related to immunoblastic lymphomas, less so to plasmacytomas of Fasl mutant and SJL mice, and least to plasmacytic plasmacytomas of IL6 transgenic mice. Plasmablastic tumors seemed to develop in an inflammatory environment associated with gene signatures of T cells, natural killer cells, and macrophages not seen with plasmacytic plasmacytomas. Plasmablastic plasmacytomas from NFS.V(+) and SJL-beta2M(-/-) mice did not have structural alterations in Myc or T(12;15) translocations and did not express Myc at high levels, regular features of transgenic and pristane-induced plasmacytomas. These findings imply that, as for human multiple myeloma, Myc-independent routes of transformation contribute to the pathogenesis of these tumors. These findings suggest that plasma cell neoplasms of mice and humans exhibit similar degrees of complexity. Mouse plasmacytomas, previously considered to be homogeneous, may thus be as diverse as their human counterparts with respect to oncogenic mechanisms of plasma cell transformation. Selecting specific types of mouse plasmacytomas that relate most closely to subtypes of human multiple myeloma may provide new opportunities for preclinical testing of drugs for treatment of the human disease.

Changes in the serum proteome were identified during early, fulminant, and recovery phases of liver injury from acetaminophen in the rat. Male F344 rats received a single, noninjury dose or a high, injury-producing dose of acetaminophen for evaluation at 6 to 120 h. Two-dimensional gel electrophoresis of immunodepleted serum separated approximately 800 stained proteins per sample from which differentially expressed proteins were identified by mass spectrometry. Serum alanine aminotransferase/aspartate aminotransferase levels and histopathology revealed the greatest liver damage at 24 and 48 h after high-dose acetaminophen corresponding to the time of greatest serum protein alterations. After 24 h, 68 serum proteins were significantly altered of which 23 proteins were increased by >5-fold and 20 proteins were newly present compared with controls. Only minimal changes in serum proteins were noted at the low dose without any histopathology. Of the 54 total protein isoforms identified by mass spectrometry, gene ontology processes for 38 unique serum proteins revealed involvement of acute phase response, coagulation, protein degradation, intermediary metabolism, and various carrier proteins. Elevated serum tumor necrosis factor-alpha from 24 to 48 h suggested a mild inflammatory response accompanied by increased antioxidant capability demonstrated by increased serum catalase activity. Antibody array and enzyme-linked immunosorbent assay analyses also showed elevation in the chemokine monocyte chemoattractant protein-1 and the metalloprotease inhibitor tissue inhibitor of metalloproteinases-1 during this same period of liver injury. This study demonstrates that serum proteome alterations probably reflect both liver damage and a concerted, complex response of the body for organ repair and recovery during acute hepatic injury.

Detection of serum markers for pancreatic cancer has been elusive. Although CA 19-9 is most commonly used, its sensitivity and specificity are modest. We used large-scale proteomics to identify potential serum markers for pancreatic cancer. Samples were analyzed using high-resolution two-dimensional gel electrophoresis to identify differentially expressed proteins in 32 normal and 30 pancreatic cancer patients. Up to 1,744 protein spots were resolved for each serum sample. Candidate proteins were identified using mass spectrometry. ANOVA was used to identify proteins that could discriminate cancer from normal sera. Serum fibrinogen level was also measured using enzymatic assay. Immunohistochemistry was used to detect fibrinogen in resected pancreatic cancers. One hundred fifty-four proteins were commonly overexpressed in all pancreatic cancers. Nine protein spots (four with identifications by mass spectrometry) could effectively separate cancer from normal controls using cross-validation. These proteins successfully discriminated all pancreatic cancer samples (30 of 30) and 94% of normal (30 of 32) samples. Prominent among these candidates was fibrinogen gamma, which was subsequently confirmed to be overexpressed in pancreatic cancer sera by enzymatic analysis (54.1 +/- 64.1 versus 0.0 +/- 0.0 mg/dL, P < 0.05) and tissue by immunohistochemistry (67% versus 29%, P < 0.05) relative to normal pancreas. Proteomic analysis combining two-dimensional gel electrophoresis and mass spectrometry successfully identified 154 potential serum markers for pancreatic cancer. Of these, fibrinogen gamma, a protein associated with the hypercoagulable state of pancreatic cancer, discriminated cancer from normal sera. Fibrinogen is a potential tumor marker in pancreatic cancer.

Interferon (IFN) consensus sequence-binding protein/IFN regulatory factor 8 (IRF8) is a transcription factor that regulates the differentiation and function of macrophages, granulocytes, and dendritic cells through activation or repression of target genes. Although IRF8 is also expressed in lymphocytes, its roles in B cell and T cell maturation or function are ill defined, and few transcriptional targets are known. Gene expression profiling of human tonsillar B cells and mouse B cell lymphomas showed that IRF8 transcripts were expressed at highest levels in centroblasts, either from secondary lymphoid tissue or transformed cells. In addition, staining for IRF8 was most intense in tonsillar germinal center (GC) dark-zone centroblasts. To discover B cell genes regulated by IRF8, we transfected purified primary tonsillar B cells with enhanced green fluorescent protein-tagged IRF8, generated small interfering RNA knockdowns of IRF8 expression in a mouse B cell lymphoma cell line, and examined the effects of a null mutation of IRF8 on B cells. Each approach identified activation-induced cytidine deaminase (AICDA) and BCL6 as targets of transcriptional activation. Chromatin immunoprecipitation studies demonstrated in vivo occupancy of 5' sequences of both genes by IRF8 protein. These results suggest previously unappreciated roles for IRF8 in the transcriptional regulation of B cell GC reactions that include direct regulation of AICDA and BCL6.

Germline mutations in Fas and Fasl induce nonmalignant T cell hyperplasia and systemic autoimmunity and also greatly increase the risk of B cell neoplasms. B lymphomas occurring in Fasl mutant (gld) mice usually are immunoglobulin (Ig) isotype switched, secrete Ig, and are plasmacytoid in appearance but lack Myc translocations characteristic of other plasma cell (PC) neoplasms. Here, we explore the relationship between B cell autoreactivity and transformation and use gene expression profiling to further classify gld plasmacytoid lymphomas (PLs) and to identify genes of potential importance in transformation. We found that the majority of PLs derive from antigen-experienced autoreactive B cells producing antinuclear antibody or rheumatoid factor and exhibit the skewed Ig V gene repertoire and Ig gene rearrangement patterns associated with these specificities. Gene expression profiling revealed that both primary and transplanted PLs share a transcriptional profile that places them at an early stage in PC differentiation and distinguishes them from other B cell neoplasms. In addition, genes were identified whose altered expression might be relevant in lymphomagenesis. Our findings provide a strong case for targeted transformation of autoreactive B cells in gld mice and establish a valuable model for understanding the relationship between systemic autoimmunity and B cell neoplasia.