Bcl10 is one of the apoptosis regulatory protein. It is located at 1p22,one site harbor tumor suppressor tumor gene. We screen Bcl10 expression in different tumor cell lines by reverse transcription-polymerase chain reaction(RT-PCR), western blot(WB) and immunohistochemistry(IHC). The results showed Bcl10 genomic expression was found in U87, Astrocytoma and no expression in glioma , glioblastoma. There were cell lines with expressions in Bcl10 protein and NF-£eB including hepatocellular carcinoma, glioblastoma, and breast cancer, but increased in lung cancer cell line. In immunohistochemistry,we found the Bcl10 protein has positive finding in glioma U373, U251; oral cancer CA922, SAS, clinical patient VGH283; Lung cancer PC14, PC13; Hepatoma Huh7; Colon cancer SW 480; Cervical cancer HeLa. The Bcl10 gene, unlike other tumor suppressor genes such as p53, may be selectively targeted by different human tumors. In our study, Bcl10 play a role in brain tumor, oral cancer and some tumor cell line had not been reported before.

Thesis (Ph.D.)--Kent State University, 2008. / Title from PDF t.p. (viewed Jan. 26, 2010). Advisor: Bansidhar Datta. Keywords: p67, ERK1, ERK2, oncogenic KRasV12, tumor suppressor. Includes bibliographical references (p. 143-160).

MOB (Mps One Binder) is a conserved gene family found in all major kingdoms. The MOB genes are essential components acting in mitotic exit and cytokinesis in both budding and fission yeasts. They are further identified as tumor suppressors in Drosophila (D.) melanogaster. Recently, they are found to be involved in the emerging Drosophila Hippo-LATS tumor suppressor pathway. Seven human homologs of yeast MOB (hMOB1A, 1B, 2A, 2B, 3, 4, 5) have been discovered. The hMOB1B is the gene that has been extensively studied and is reported to be required for the activation of LATS (Large Tumor Suppressor)/NDR (Nuclear Dbf2-related) protein kinase family, however, the functional significance of the gene remains unknown. This study is the first to elucidate the biological and biochemical functions of all seven human MOBs. By examining hMOB mRNA expression in various human tissues, we found that the hMOBs have exhibited different expression patterns. We also investigated the subcellular localization of hMOBs during interphase through immunofluorescent analysis. While hMOB2A is localized in the cytoplasm, hMOB4 is exclusively found in the nucleus. All of the other hMOBs are localized in both cytoplasm and nucleus. Furthermore, we identified hMOB1A and hMOB1B as the main binding partners of LATS and NDR in vitro. Additionally, we successfully identified a region on hMOB1B for the interaction with LATS or NDR and determined the crucial residue that is responsible for the binding of LATS2 with hMOB1B. Most significantly, we found that over-expression of hMOB1B in human cancer cells inhibits cell proliferation and induces cell death. Moreover, hMOB1B when targeted to the plasma membrane dramatically enhances the phenotype. Conversely, small interfering (si) RNA-mediated suppression of either endogenous hMOB1A or hMOB1B causes increased cell proliferation, whereas suppression of both hMOB1A and hMOB1B demonstrates a more significant enhancement in tumor cell growth. Moreover, co-expression of both LATS and hMOB1B targeted to the plasma membrane completely abolishes cell proliferation. Our findings provide convincing evidence that hMOB1A and hMOB1B function as negative regulators of cell proliferation and as pro-apoptotic proteins. Understanding hMOBs functions in the cell and their possible role in tumorigenesis can provide important information for the diagnosis and treatment of human cancers. / Thesis (Master, Pathology & Molecular Medicine) -- Queen's University, 2008-09-23 14:18:43.896

Thesis (M.S.)--Marshall University, 2008. / Title from document title page. Includes abstract. Document formatted into pages: contains vi, 69 p. : ill. Includes bibliographical references (p. 59-65).

Thesis (M.S.)--Marshall University, 2008. / Title from document title page. Includes abstract. Document formatted into pages: contains 59 p. Includes bibliographical references (p. 55-59.)

Deletion on the short arm of chromosome 3 is one of the most important genetic abnormalities in the tumorigenesis of nasopharyngeal carcinoma (NPC). Both physical mapping and functional studies have targeted an NPC-related tumor suppressor gene(s) to chromosome 3p21.3. Our group has previously reported that the Ras Association Domain Family 1A (RASSF1A) gene, located within a 120-kb minimal deleted region on 3p21.3, was frequently inactivated by promoter hypermethylation in NPC. These findings suggest that RASSF1A may be a critical tumor suppressor gene in NPC. In this study, the functions of RASSF1A in NPC was characterized with the following specific aims: (1) the role of RASSF1A as a tumor suppressor in NPC cells; (2) the identification of novel RASSF1A-modulated genes and pathways in NPC; (3) the effect of RASSF1A knockdown in immortalized nasopharyngeal epithelial cells; (4) the aberrant transcription and epigenetic changes of other RASSF family of genes ( RASSFS/NORE1 and RASSF4/AD037) in NPC. / In summary, RASSF1A is a major tumor suppressor gene from 3p21.3 in NPC. RASSF1A may exert its tumor suppressor function through various biochemical pathways. The novel findings from this study revealed the role of RASSF1A in the tumorigenesis of NPC. It also led to the better understanding of the molecular pathogenesis of this endemic cancer. (Abstract shortened by UMI.) / RASSF1A is a member of the RASSF family of proteins characterized by a consensus Ras-association domain at the C-terminus. The expression and methylation status of two other members of RASSF gene family, RASSF4/AD037 and RASSF5/NORE1, were investigated in NPC. The study showed that RASSF1A, but not other members of the RASSF family, is the target tumor suppressor in this particular cancer type. / Restoration of wild-type RASSF1A, by means of transfection, in a RASSF1A-deficient NPC cell line (C666-1) led to marked growth inhibition in the NPC cells. Isolated stable clones expressing RASSF1A demonstrated retarded cell proliferation in vitro . Soft-agar assay showed decreased number and sizes of colonies formed by these clones. The expression of RASSF1A in NPC cells also led to a dramatic reduction in tumorigenic potential in nude mice. The findings provide functional evidence that RASSF1A is a target tumor suppressor gene on 3p21.3 in NPC. / Chow Shuk Nga Lillian. / "May 2005." / Adviser: Kwok Wai Lo. / Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3588. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 112-124). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

published_or_final_version / abstract / Pathology / Master / Master of Philosophy

²Ä¤@³¡¥÷ Nasopharyngeal carcinoma¡]NPC¡^ is a malignant tumor which occurs at high incidence in southern China. Several risk factors have now been recognized, but the molecular mechanism of this disease is not well understood. To investigate the c-myc¡Bcyclin D1¡Bp16¡Bp27 and Rb gene expression in NPC at protein level, 46 cases of nasopharyngeal carcinoma in southern Taiwan were detected by immunohistochemistry. There was no detectable p16 in 31/45 cases¡]69¢M¡^¡F 34/46 cases¡]73.9¢M¡^had intense staining for the Rb protein¡F 29¡]70.7¢M¡^of 41 cases had c-myc protein expression¡Fcyclin D1 was not overexpression in nasopharyngeal carcinoma¡F 32¡]69.6¢M¡^of 46 cases had high level expression of p27, which was inverse correlation with other tumors. No expression of c-myc protein correlated with higher neck metastasis¡]P¡Õ0.05¡^. No correlation was found between other proteins and any of the clinicopathological parameters. ²Ä¤G³¡¥÷ To better understand nasopharyngeal carcinoma¡]NPC¡^, we have newly established two NPC cell lines. Biopsy specimens from NPC patients were collected, primary culture were set up. Two NPC cell lines were established¡GNPCGK 01 was derived from differentiated carcinoma and NPCGK 02 was derived from undifferentiated carcinoma. Two cell lines have been passaged for more than 25 times. Two cell lines had telomerase activity¡Fstrong expression of hTERT gene and keratin-19 gene were also observed. TGF£] RI protein expression of these NPC cell lines is higher than normal epithelial cell.The oncogenes, c-myc¡Bc-fos and cyclin D1 were overexpressed. The Rb protein was expressed stronger than normal epithelial cells. NPCGK 01 that was derived from differentiated carcinoma had p16 down-regulation and p27 gene not expression, but p21 protein had excess expression. In short, two cell lines had cancer cell characteristics, oncoproteins were overexpression and tumor suppressor proteins were abnormal expression. This result may lead to tumorigenesis of nasopharyngeal carcinoma.

NK cell lymphoma is one of the cellular malignancies that arise from lymphocytes. Due to its rarity and aggressiveness the detailed molecular pathogenesis of NK cell lymphoma remains to be discovered. There are recent studies showing that the master regulator of B-cell differentiation into plasma cells, the Positive Regulatory Domain containing 1, with ZNF domain(PRDM1) has tumor suppressive function not only in diffuse large B-cell lymphoma (DLBCL), but also in NK cell lymphoma. The PRDM1 has two isoforms, αand β, where the former one is a functional isoform and the latter is a defective isoform with shortened and disrupted positive regulatory domain formed from transcription of internal promoter. By semi -quantitative RT-PCR, PRDM1-αexpression was found to be absent in 80% (4/5) NK cell lines while present in the normal NK cells. Loss of PRDM1 expression suggests its role as tumor suppressor. In order to study the tumor suppressive role of the αisoform of PRDM1, short-hairpin RNA (shRNA) with isoform specific sequence is used to knockdown the expression of PRDM1-αin NK cell lines. Western blot result showed about 40% decrease of PRDM1-αprotein after knockdown. Retroviral infection of the NK cell lines, NKYS and YT which have endogenous α-isoforms of expression, for the delivery of the shRNA was done and were subsequently subjected to in vitro functional analyses including MTS assay, colony formation assay, cell viability test and cell cycle analysis to determine potential effect of the loss of PRDM1-αon the NK cell lines. The PRDM1-αprotein isoform is expected to be able to repress excessive growth of NK cell line. When this isoform is inactivated, the NK cell lines are expected to proliferate significantly than the negative control counterpart in functional analyses. However in this study only YTcell line showed significant proliferation advantage in MTS and colony formation assay after the knockdown of PRDM1-α by shRNA. Cell viability assays and cell cycle analyses failed to show significant changes in both NK cell lines and yet even showed inhibitory effect after the knockdown of the gene. Ectopic expression of PRDM1-αby retroviral infection was done in KHYG cell line to further evaluate its tumor suppressive function. Apoptotic assay on the KHYG cells with ectopic expression of PRDM1-αwas performed and percentage of cells with late apoptosis was found to be significantly higher in this cell line. This suggests that one of the mechanisms for PRDM1-αto act as tumor suppressor is via the apoptosis pathway which in turn promotes the cell death. Future studies will be made to further investigate the effects of knockdown of PRDM-1αby designing another shRNA sequence which knockdown the expression of gene by at least 50% and to further investigate the role of PRDM1-αinthe pathogenesis NK cell lymphomaby proliferation assays, colony formation assay and cell cycle analysis. / published_or_final_version / Pathology / Master / Master of Medical Sciences

Cutaneous melanoma is an increasingly common skin cancer characterized by aggressive metastatic growth and poor prognosis. The mechanisms behind melanoma progression are not fully understood, but emerging evidence suggests that a group of newly discovered small regulatory RNAs, named microRNAs (miRNAs), plays an important role. miRNAs are ~ 22 nucleotide single strand non-coding RNAs that post-transcriptionally regulate gene expression by binding to target messenger RNAs (mRNAs), leading to mRNA degradation and translation inhibition. Abnormal expression of miRNAs has been observed in human malignancies and is associated with tumorigenesis. The main goals of this thesis are to investigate miRNA dysregulation in melanoma and to identify potential miRNAs involved in melanoma pathogenesis. Initially, the expression of 470 miRNAs was profiled in 8 metastatic melanoma and 8 benign nevus tissue samples. We discovered unique miRNA expression profiles and identified differentially expressed miRNAs in melanomas as compared to nevi. miR-193b was one of the most significantly downregulated miRNAs in melanoma, and its function and regulatory targets were unknown. Subsequently, in vitro functional studies revealed that ectopic expression of miR-193b in melanoma cells drastically repressed cell proliferation and migration. Although it does not directly induce apoptosis in melanoma cells, miR-193b does sensitize these cells to ABT-737-mediated cell death. In concert with functional studies, gene expression analysis and in silico target prediction were performed to globally screen for mRNA targets of miR-193b. We identified eighteen genes as candidates in that they were downregulated by miR-193b and contained predicted miR-193b binding sites. Based on their known biological functions, three genes were particularly interesting: cyclin D1 (CCND1), myeloid cell leukemia sequence 1 (Mcl-1), and stathmin 1 (STMN1). CCND1 and Mcl-1 are two well-known melanoma oncogenes, and we validated their role in cell proliferation and apoptosis respectively. Furthermore, using similar approach, we were the first to identify STMN1 as a novel melanoma oncogene. We demonstrated that CCND1, Mcl-1, and STMN1 were directly regulated by miR-193b. During melanoma progression, reduced expression of miR-193b may promote cell proliferation, migration and survival. Taken together, this thesis describes the dysregulation of miRNAs in melanoma and demonstrates that miR-193b functions as a tumor suppressor. / Thesis (Ph.D, Pathology & Molecular Medicine) -- Queen's University, 2012-05-31 15:27:01.707