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1.
Opt Lett ; 47(3): 557-560, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35103670

RESUMO

A compact optical layout of a pulse shaper for strongly chirped laser pulses of nanosecond time scale exploiting a tilted chirped volume Bragg grating and a programmable spatial light modulator is proposed. The setup has a non-zero frequency dispersion; thus it may be used for stretching or compressing the pulse and controlling its shape simultaneously. The feasibility of spectral shaping with a resolution of 0.16 nm, corresponding to a time resolution of 150 ps, and a contrast ratio of 102 is demonstrated experimentally.

2.
J Cell Biochem ; 121(8-9): 3986-3999, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31803961

RESUMO

The intramural the National Cancer Institute (NCI) and more recently the University of Texas Southwestern Medical Center with many different collaborators comprised a complex, multi-disciplinary team that collaborated to generated large, comprehensively annotated, cell-line related research resources which includes associated clinical, and molecular characterization data. This material has been shared in an anonymized fashion to accelerate progress in overcoming lung cancer, the leading cause of cancer death across the world. However, this cell line collection also includes a range of other cancers derived from patient-donated specimens that have been remarkably valuable for other types of cancer and disease research. A comprehensive analysis conducted by the NCI Center for Research Strategy of the 278 cell lines reported in the original Journal of Cellular Biochemistry Supplement, documents that these cell lines and related products have since been used in more than 14 000 grants, and 33 207 published scientific reports. This has resulted in over 1.2 million citations using at least one cell line. Many publications involve the use of more than one cell line, to understand the value of the resource collectively rather than individually; this method has resulted in 2.9 million citations. In addition, these cell lines have been linked to 422 clinical trials and cited by 4700 patents through publications. For lung cancer alone, the cell lines have been used in the research cited in the development of over 70 National Comprehensive Cancer Network clinical guidelines. Finally, it must be underscored again, that patient altruism enabled the availability of this invaluable research resource.

3.
Life (Basel) ; 13(6)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37374129

RESUMO

Recent publications on gall formation induced on the leaves of dicotyledonous flowering plants by eriophyoid mites (Eriophyoidea) and representatives of four insect orders (Diptera, Hemiptera, Hymenoptera, Lepidoptera) are analyzed. Cellular and molecular level data on the stimuli that induce and sustain the development of both mite and insect galls, the expression of host plant genes during gallogenesis, and the effects of these galling arthropods on photosynthesis are considered. A hypothesis is proposed for the relationship between the size of galls and the volume of secretions injected by a parasite. Multistep, varying patterns of plant gene expression and accompanying histo-morphological changes in the transformed gall tissues are apparent. The main obstacle to better elucidating the nature of the induction of gallogenesis is the impossibility of collecting a sufficient amount of saliva for analysis, which is especially important in the case of microscopic eriophyoids. The use of modern omics technologies at the organismal level has revealed a spectrum of genetic mechanisms of gall formation at the molecular level but has not yet answered the questions regarding the nature of gall-inducing agents and the features of events occurring in plant cells at the very beginning of gall growth.

4.
Analyst ; 136(16): 3295-302, 2011 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-21743916

RESUMO

A novel laser electrodispersion (LE) technique was employed to deposit gold nanoparticles onto Si and SiO(x) surfaces. The LE technique combines laser ablation with cascade fission of liquid metal micro-drops, which results in the formation of nanoparticles upon rapid cooling. The shape and the size distribution of the Au nanoparticles prepared by LE depend on the nature of the support. Gold nanoparticles were also deposited in the channels of microreactors fabricated by wet etching of Si and used as SE(R)RS sensors. The influence of the nanoparticle surface density as well as of the nature of the substrate on the Raman response was studied. At an appropriate surface density of the deposited nanoparticles a significant enhancement of Raman signal was observed showing the possibility to create efficient SERS substrates. Application of microfluidic devices in surface enhanced Raman spectroscopy (SERS) in continuous-flow mode with sensor regeneration is described.

5.
Biodivers Data J ; 8: e59249, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33244292

RESUMO

BACKGROUND: The "Flora of Russia" project on iNaturalist brought together professional scientists and amateur naturalists from all over the country. Over 10,000 people were involved in the data collection. NEW INFORMATION: Within 20 months, the participants accumulated 750,143 photo observations of 6,857 species of the Russian flora. This constitutes the largest dataset of open spatial data on the country's biodiversity and a leading source of data on the current state of the national flora. About 87% of all project data, i.e. 652,285 observations, are available under free licences (CC0, CC-BY, CC-BY-NC) and can be freely used in scientific, educational and environmental activities.

6.
Cancer Lett ; 257(2): 199-205, 2007 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-17720308

RESUMO

Reduced expression or loss of tumor suppressor genes play a key role in many cancers. In this study, we investigated the role of RASSF1A in the pathogenesis of esophageal squamous cell carcinoma (ESCC) and nasopharyngeal carcinoma (NPC). We detected the down-regulated expression of both RASSF1A transcripts and protein in tumor tissues using RT-PCR and tissue microarray immunohistochemical staining analyses. Down-regulated expression of RASSF1A showed a significant association with WHO grade, tumor status, and lymph node metastasis, showing its possible utility as a biomarker for clinical specimens.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Nasofaríngeas/patologia , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Western Blotting , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise Serial de Tecidos , Proteínas Supressoras de Tumor/metabolismo
7.
J Mol Biol ; 346(2): 411-22, 2005 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-15670593

RESUMO

Immune responses to invading pathogens are mediated largely through a family of transmembrane Toll-like receptors and modulated by a number of downstream effectors. In particular, a family of four interleukin 1 receptor-associated kinases (IRAK) regulates responsiveness to bacterial endotoxins. Pharmacological targeting of particular IRAK components may be beneficial for treatment of bacterial infections. Here, we studied transcriptional regulation of the human IRAK2 gene. Analysis of the IRAK2 promoter region reveals putative binding sites for several transcriptional factors, including ZIP (EGR1 and SP1), CTCF and AP-2beta. Deletion of the ZIP or AP-2 sites did not significantly affect IRAK2 promoter activity in naive and endotoxin-treated mononuclear cells, in dormant and activated Jurkat T-cells, in lung and kidney cells. In contrast, we found that CTCF plays a major role in IRAK2 transcription. An electrophoretic mobility shift assay of the DNA fragments containing the IRAK2 CpG island, revealed a single high-affinity binding site for the transcriptional regulator and a chromatin insulator protein, CTCF. This assay revealed a CTCF-binding site within the mouse Irak2 promoter. The presence of the CTCF protein in human IRAK2 promoter was confirmed by chromatin immunoprecipitation assay. Specific residues that interacted with the CTCF protein, were identified by methylation interference assay. In all cell lines analyzed, including cells of lung, renal, monocytic and T-cell origin, the IRAK2 luciferase reporter construct, containing an intact CTCF-binding site, showed strong promoter activity. However, IRAK2 promoter activity was decreased dramatically for the constructs with a mutated CTCF-binding site.


Assuntos
Proteínas de Ligação a DNA/genética , Regiões Promotoras Genéticas , Proteínas Quinases/genética , Proteínas Repressoras/genética , Animais , Sequência de Bases , Sítios de Ligação , Fator de Ligação a CCCTC , Células Cultivadas , Ilhas de CpG , Metilação de DNA , Regulação da Expressão Gênica , Humanos , Quinases Associadas a Receptores de Interleucina-1 , Camundongos , Dados de Sequência Molecular , Fatores de Transcrição , Transcrição Gênica
8.
Cancer Res ; 63(8): 1888-93, 2003 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-12702579

RESUMO

Recently, we have identified a new putative tumor suppressor gene, RASSF1A (Ras association domain family 1A gene), located at human chromosome 3p21.3, the segment that is often lost in many types of human cancers. The RASSF1A promoter was shown to be frequently hypermethylated in various epithelial tumors, including small cell lung, breast, bladder, prostate, gastric, and renal cell carcinomas. In this study, we have analyzed the methylation status of the RASSF1A gene in primary human cervical cancers and in eight cervical cancer cell lines. The RASSF1A promoter is hypermethylated in 4 of 42 (= 10%) of squamous cell carcinomas, in 4 of 19 (= 21%) of adenosquamous carcinomas, and in 8 of 34 (= 24%) of cervical adenocarcinomas. Although in adenocarcinomas, methylation of RASSF1A and presence of human papillomavirus (HPV) type 16 or 18 sometimes coexisted, not a single case of HPV-16/18-positive squamous cell carcinomas had RASSF1A methylation. Similarly, in all eight analyzed cervical cell lines, RASSF1A inactivation and HPV infection were mutually exclusive (Fisher's exact test; P = 0.0357): two HPV-negative cervical cancer cell lines had a methylated and silenced RASSF1A promoter (C-33A and HT-3), whereas the other six HPV-positive lines expressed RASSF1A mRNA (ME 180, MS751, SiHa, C-4I, HeLa, and CaSki). For cervical tumors and cell lines combined, the Pearson's chi(2) test (chi(2) = 3.99; P

Assuntos
Inativação Gênica , Proteínas de Neoplasias/genética , Infecções por Papillomavirus/genética , Proteínas Supressoras de Tumor , Infecções Tumorais por Vírus/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia , Metilação de DNA , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Humanos , Proteínas de Neoplasias/biossíntese , Infecções por Papillomavirus/complicações , Regiões Promotoras Genéticas , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Infecções Tumorais por Vírus/complicações , Neoplasias do Colo do Útero/metabolismo
9.
Cancer Res ; 64(18): 6438-43, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15374952

RESUMO

Initial analysis identified the NPRL2/G21 gene located in 3p21.3C, the lung cancer region, as a strong candidate tumor suppressor gene. Here we provide additional evidence of the tumor suppressor function of NPRL2/G21. The gene has highly conserved homologs/orthologs ranging from yeast to humans. The yeast ortholog, NPR2, shows three highly conserved regions with 32 to 36% identity over the whole length. By sequence analysis, the main product of NPRL2/G21 encodes a soluble protein that has a bipartite nuclear localization signal, a protein-binding domain, similarity to the MutS core domain, and a newly identified nitrogen permease regulator 2 domain with unknown function. The gene is highly expressed in many tissues. We report inactivating mutations in a variety of tumors and cancer cell lines, growth suppression of tumor cells with tet-controlled NPRL2/G21 transgenes on plastic Petri dishes, and suppression of tumor formation in SCID mice. Screening of 7 renal, 5 lung, and 7 cervical carcinoma cell lines showed homozygous deletions in the 3' end of NPRL2 in 2 renal, 3 lung, and 1 cervical (HeLa) cell line. Deletions in the 3' part of NPRL2 could result in improper splicing, leading to the loss of the 1.8 kb functional NPRL2 mRNA. We speculate that the NPRL2/G21 nuclear protein may be involved in mismatch repair, cell cycle checkpoint signaling, and activation of apoptotic pathway(s). The yeast NPR2 was shown to be a target of cisplatin, suggesting that the human NPRL2/G21 may play a similar role. At least two homozygous deletions of NPRL2/G21 were detected in 6 tumor biopsies from various locations and with microsatellite instability. This study, together with previously obtained results, indicates that NPRL2 is a multiple tumor suppressor gene.


Assuntos
Cromossomos Humanos Par 3/genética , Genes Supressores de Tumor , Neoplasias/genética , Proteínas Supressoras de Tumor/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Pequenas/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , Neoplasias Renais/genética , Neoplasias Pulmonares/genética
10.
Cancer Res ; 62(12): 3498-502, 2002 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-12067994

RESUMO

We analyzed expression status of the recently identified tumor suppressor geneRASSF1A in primary prostate carcinomas and in prostate cell lines. We found complete methylation of the RASSF1A promoter in 63% of primary microdissected prostate carcinomas (7 of 11 samples). The remaining 4 samples (37%) were partially methylated, possibly because of contamination with normal cells. No promoter methylation was observed in matching normal prostate tissues. High levels of RASSF1A transcript and no methylation of RASSF1A promoter were found in explanted primary normal prostate epithelial and stromal cells. Complete silencing and methylation of RASSF1A promoter was observed in five widely used prostate carcinoma cell lines, which acquired the ability to grow in culture spontaneously, including LNCaP, PC-3, ND-1, DU-145, 22Rv1, and one primary prostate carcinoma immortalized by overexpression of the human telomerase catalytic subunit (RC-58T/hTERT). However, no silencing of RASSF1A was found in four other prostate carcinoma cell lines, which were adapted for cell culture after transformation with human papillomaviral DNA. Suppression of cell growth in vitro was demonstrated after the reintroduction of RASSF1A-expressing construct into LNCaP prostate carcinoma cells. Our data implicate the RASSF1A gene in human prostate tumorigenesis.


Assuntos
Inativação Gênica , Genes Supressores de Tumor , Proteínas de Neoplasias/genética , Neoplasias da Próstata/genética , Proteínas Supressoras de Tumor , Divisão Celular/genética , Transformação Celular Viral , Metilação de DNA , Proteínas de Ligação a DNA , Células Epiteliais/metabolismo , Células Epiteliais/fisiologia , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Proteínas de Neoplasias/biossíntese , Papillomaviridae/fisiologia , Regiões Promotoras Genéticas , Próstata/citologia , Próstata/metabolismo , Próstata/fisiologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Células Estromais/metabolismo , Células Estromais/fisiologia , Telomerase/genética , Células Tumorais Cultivadas
11.
Clin Cancer Res ; 9(10 Pt 1): 3635-40, 2003 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-14506151

RESUMO

PURPOSE: RASSF1A, a recently identified candidate tumor suppressor gene, was found to be inactivated in lung cancer and other tumor types. We sought to understand the role of RASSF1A in head and neck cancer. EXPERIMENTAL DESIGN: We analyzed the status of RASSF1A and presence of high-risk human papilloma virus (HPV) in head and neck cancer squamous cell carcinoma (HNSCC) cell lines and primary tumors. We used methylation-specific PCR to detect promoter hypermethylation and direct sequence analysis to detect point mutations in primary tumors and cell lines. 5-aza-2-deoxycytidine was used to demethylate the RASSF1A promoter in cell lines. RESULTS: Promoter methylation of RASSF1A was detected in 42.9% (3 of 7) cell lines and 15% (7 of 46) primary tumors but not in the normal control DNA. Direct sequence analysis revealed a point mutation in a cell line and another in a primary HNSCC. After treatment with 5-aza-2-deoxycytidine, re-expression and demethylation of RASSF1A gene were detected in cell lines with promoter hypermethylation. HPV DNA was detected in 34.7% (16 of 46) primary HNSCC. We found a significant inverse correlation between RASSF1A promoter methylation and HPV infection (P = 0.038). CONCLUSIONS: Our results suggest that RASSF1A is inactivated in a subset of HNSCC primary tumors. Moreover, an inverse correlation between RASSF1A and HPV supports a biological mechanism in which both RASSF1A promoter methylation and HPV infection abrogate the same pathway in tumorigenesis.


Assuntos
Azacitidina/análogos & derivados , Carcinoma/genética , Neoplasias de Cabeça e Pescoço/genética , Proteínas Supressoras de Tumor/genética , Azacitidina/farmacologia , Carcinoma/virologia , Linhagem Celular Tumoral , DNA/metabolismo , Metilação de DNA , Decitabina , Regulação para Baixo , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Repetições de Microssatélites , Papillomaviridae/metabolismo , Mutação Puntual , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Isoformas de Proteínas , RNA/metabolismo , Análise de Sequência de DNA , Sulfitos/farmacologia , Proteína Supressora de Tumor p53/metabolismo
12.
PLoS One ; 4(5): e5231, 2009 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-19478941

RESUMO

BACKGROUND: Many different genetic alterations are observed in cancer cells. Individual cancer genes display point mutations such as base changes, insertions and deletions that initiate and promote cancer growth and spread. Somatic hypermutation is a powerful mechanism for generation of different mutations. It was shown previously that somatic hypermutability of proto-oncogenes can induce development of lymphomas. METHODOLOGY/PRINCIPAL FINDINGS: We found an exceptionally high incidence of single-base mutations in the tumor suppressor genes RASSF1 and RBSP3 (CTDSPL) both located in 3p21.3 regions, LUCA and AP20 respectively. These regions contain clusters of tumor suppressor genes involved in multiple cancer types such as lung, kidney, breast, cervical, head and neck, nasopharyngeal, prostate and other carcinomas. Altogether in 144 sequenced RASSF1A clones (exons 1-2), 129 mutations were detected (mutation frequency, MF = 0.23 per 100 bp) and in 98 clones of exons 3-5 we found 146 mutations (MF = 0.29). In 85 sequenced RBSP3 clones, 89 mutations were found (MF = 0.10). The mutations were not cytidine-specific, as would be expected from alterations generated by AID/APOBEC family enzymes, and appeared de novo during cell proliferation. They diminished the ability of corresponding transgenes to suppress cell and tumor growth implying a loss of function. These high levels of somatic mutations were found both in cancer biopsies and cancer cell lines. CONCLUSIONS/SIGNIFICANCE: This is the first report of high frequencies of somatic mutations in RASSF1 and RBSP3 in different cancers suggesting it may underlay the mutator phenotype of cancer. Somatic hypermutations in tumor suppressor genes involved in major human malignancies offer a novel insight in cancer development, progression and spread.


Assuntos
Mutação/genética , Neoplasias/genética , Proteínas Supressoras de Tumor/genética , Desaminase APOBEC-1 , Animais , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Células Clonais , Biologia Computacional , Citidina Desaminase/metabolismo , DNA Bacteriano/genética , DNA Complementar/genética , Proteínas de Escherichia coli/genética , Etiquetas de Sequências Expressas , Efeito Fundador , Genoma/genética , Hematopoese/genética , Humanos , Neoplasias Renais/genética , Neoplasias Renais/patologia , Camundongos , Camundongos SCID , Reação em Cadeia da Polimerase
13.
J Biol Chem ; 277(42): 39887-98, 2002 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-12169691

RESUMO

The von Hippel-Lindau disease gene (VHL) is the causative gene for most adult renal cancers. However, the mechanism by which VHL protein functions as a renal tumor suppressor remains largely unknown. To identify low occupancy VHL protein partners with potential relevance to renal cancer, we screened a human kidney library against human VHL p30 using a yeast two-hybrid approach. Jade-1 (gene for Apoptosis and Differentiation in Epithelia) encodes a previously uncharacterized 64-kDa protein that interacts strongly with VHL protein and is most highly expressed in kidney. Jade-1 protein is short-lived and contains a candidate destabilizing (PEST) motif and plant homeodomains that are not required for the VHL interaction. Jade-1 is abundant in proximal tubule cells, which are clear-cell renal cancer precursors, and expression increases with differentiation. Jade-1 is expressed in cytoplasm and the nucleus diffusely and in speckles, where it partly colocalizes with VHL. VHL reintroduction into renal cancer cells increases endogenous Jade-1 protein abundance up to 10-fold. Furthermore, VHL increases Jade-1 protein half-life up to 3-fold. Thus, direct protein stabilization is identified as a new VHL function. Moreover, Jade-1 protein represents a novel candidate regulatory factor in VHL-mediated renal tumor suppression.


Assuntos
Proteínas de Homeodomínio/fisiologia , Ligases/fisiologia , Proteínas Supressoras de Tumor , Ubiquitina-Proteína Ligases , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Western Blotting , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Biblioteca Gênica , Proteínas de Homeodomínio/química , Humanos , Imuno-Histoquímica , Rim/metabolismo , Ligases/metabolismo , Microscopia de Fluorescência , Dados de Sequência Molecular , Plasmídeos/metabolismo , Testes de Precipitina , Ligação Proteica , Estrutura Terciária de Proteína , Fatores de Tempo , Distribuição Tecidual , Transfecção , Técnicas do Sistema de Duplo-Híbrido , Proteína Supressora de Tumor Von Hippel-Lindau
14.
Proc Natl Acad Sci U S A ; 100(8): 4580-5, 2003 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-12676986

RESUMO

The candidate tumor-suppressor gene hyaluronidase 2 (HYAL2) encodes a glycosylphosphatidylinositol-anchored cell-surface protein that serves as an entry receptor for jaagsiekte sheep retrovirus, a virus that causes contagious lung cancer in sheep that is morphologically similar to human bronchioloalveolar carcinoma. The viral envelope (Env) protein alone can transform cultured cells, and we hypothesized that Env could bind and sequester the HYAL2 receptor and thus liberate a potential oncogenic factor bound and negatively controlled by HYAL2. Here we show that the HYAL2 receptor protein is associated with the RON receptor tyrosine kinase (also called MST1R or Stk in the mouse), rendering it functionally silent. In human cells expressing a jaagsiekte sheep retrovirus Env transgene, the Env protein physically associates with HYAL2. RON liberated from the association with HYAL2 becomes functionally active and consequently activates the Akt and mitogen-activated protein kinase pathways leading to oncogenic transformation of immortalized human bronchial epithelial cells. We find activated RON in a subset of human bronchioloalveolar carcinoma tumors, suggesting RON involvement in this type of human lung cancer.


Assuntos
Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Hialuronoglucosaminidase/genética , Hialuronoglucosaminidase/metabolismo , Retrovirus Jaagsiekte de Ovinos/patogenicidade , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Linhagem Celular , Transformação Celular Viral , Cães , Regulação para Baixo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Proteínas Ligadas por GPI , Produtos do Gene env/metabolismo , Genes Supressores de Tumor , Genes env , Humanos , Retrovirus Jaagsiekte de Ovinos/genética , Retrovirus Jaagsiekte de Ovinos/metabolismo , Modelos Biológicos , Ovinos , Transdução de Sinais , Transfecção
15.
Proc Natl Acad Sci U S A ; 101(14): 4906-11, 2004 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-15051889

RESUMO

Chromosome 3p21.3 region is frequently (>90%) deleted in lung and other major human carcinomas. We subdivided 3p21.3 into LUCA and AP20 subregions and discovered frequent homozygous deletions (10-18%) in both subregions. This finding strongly implies that they harbor multiple tumor suppressor genes involved in the origin and/or development of major epithelial cancers. In this study, we performed an initial analysis of RBSP3/HYA22, a candidate tumor suppressor genes located in the AP20 region. Two sequence splice variants of RBSP3/HYA22 (A and B) were identified, and we provide evidence for their tumor suppressor function. By sequence analysis RBSP3/HYA22 belongs to a gene family of small C-terminal domain phosphatases that may control the RNA polymerase II transcription machinery. Expression of the gene was drastically (>20-fold) decreased in 11 of 12 analyzed carcinoma cell lines and in three of eight tumor biopsies. We report missense and nonsense mutations in tumors where RBSP3/HYA22 was expressed, growth suppression with regulated transgenes in culture, suppression of tumor formation in severe combined immunodeficient mice, and dephosphorylation of ppRB by RBSP3/HYA22, presumably leading to a block of the cell cycle at the G1/S boundary.


Assuntos
Genes Supressores de Tumor , Proteínas Supressoras de Tumor/genética , Sequência de Aminoácidos , Sequência de Bases , Divisão Celular/genética , Linhagem Celular Tumoral , Metilação de DNA , Primers do DNA , Sondas de DNA , Deleção de Genes , Humanos , Repetições de Microssatélites , Dados de Sequência Molecular , Fosforilação , Reação em Cadeia da Polimerase , Splicing de RNA , Homologia de Sequência de Aminoácidos , Sitios de Sequências Rotuladas , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/fisiologia
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