The influence of the total flavonoids of Hedysarum polybotry on the proliferation, cell cycle, and expressions of p21Ras and proliferating cell nuclear antigen gene in erythroleukemia cell line K562 / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of total flavonoids of Hedysarum polybotry on the proliferation, cell cycle, and expressions of p21(Ras) and proliferating cell nuclear antigen (PCNA) gene in erythroleukemia cell line K562.</p><p><b>METHODS</b>The effect of total flavonoids of Hedysarum polybotry on K562 cell line survival was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) reduction assay. The time- and dose-dependent manner was also observed. The cell cycle and apoptosis were analyzed with flow cytometry (FCM). The immunocytochemistry method was applied to quantitatively analyze the effects of flavonoids of Hedysarum polybotry on changes p21(Ras) and PCNA gene expressions.</p><p><b>RESULTS</b>Flavonoids of Hedysarum polybotry (20-100 μg/mL) significantly inhibited the proliferation of K562 cells in a time- and dose-dependent manner. After K562 cells were cultured for 48 h, total flavonoids of Hedysarum polybotry had no significant effect on the apoptosis of K562 cells but showed significantly inhibition (P<0.01), indicating that total flavonoids of Hedysarum polybotry could induce K562 cells arrested at G(0)/G(1) and G(2)/M phases. Compared with the control group, p21(Ras) and PCNA gene expressions were decreased significantly in K562 cells treated with total flavonoids of Hedysarum polybotry (40 and 80 μg/mL, respectively) for 48 h.</p><p><b>CONCLUSION</b>The inhibitory effect on proliferation of K562 cells was observed in the groups treated with flavonoids of Hedysarum polybotry, which might be related to cells arresting.</p>

Crystal structure and functional implication of the RUN domain of human NESCA

NESCA, a newly discovered signaling adapter protein in the NGF-pathway, contains a RUN domain at its N-terminus. Here we report the crystal structure of the NESCA RUN domain determined at 2.0-Å resolution. The overall fold of the NESCA RUN domain comprises nine helices, resembling the RUN domain of RPIPx and the RUN1 domain of Rab6IP1. However, compared to the other RUN domains, the RUN domain of NESCA has significantly different surface electrostatic distributions at the putative GTPase-interacting interface. We demonstrate that the RUN domain of NESCA can bind H-Ras, a downstream signaling molecule of TrkA, with high affinity. Moreover, NESCA RUN can directly interact with TrkA. These results provide new insights into how NESCA participates in the NGF-TrkA signaling pathway.

Effect of p21 gene transfection mediated by replication deficient adenovirus on the pulmonary hypertensive rat model / 中华儿科杂志

<p><b>OBJECTIVE</b>To investigate the feasibility of transferring p21 gene into lung tissue with recombinant adenovirus with full-length cDNA of p21 inserted in the Wistar rat model of pulmonary hypertension (PAH) induced by left-to-right shunt, study the expression of the desired gene in vivo, find if overexpression of desired gene can inhibit pulmonary hypertension.</p><p><b>METHODS</b>With full-length cDNA of p21 transfected HEK293 cells with clonfectin, and was packed, amplified in order to obtain the high-titer recombinant adenovirus (AdCMV-p21). The infection titer was determined by TCID50 method and was diluted into 1.67 x 10(8) pfu/L. Wistar rats were randomly allocated to control group (n = 10), model group (n = 15), test group (n = 10) and test control group (n = 10). In model group and test group left-to-right shunt pulmonary hypertension was developed by using cuff technique. AdCMV-p21 was transfected into test group and test control group using tracheal inhalation. The mPAP, mRVP and RVHI were measured and compared between every two groups. The left lung was immunohistochemically stained to observe the result of transfection. The right lung was HE stained to observe morphological changes in arteria pulmonalis and calculate WT%.</p><p><b>RESULTS</b>The mRVP, mPAP and WT% in model group and test group were significantly higher than those in control (P < 0.05), which suggested that the rat model of PAH was established successfully. Brown spots in the nucleus of VSMCs of pulmonary artery were seen in test group and test control group, which indicated that AdCMV-p21 was transfected successfully. The rate of transfected cells in test group was (42.8 +/- 11.6)%, which was equal to that of test control group (P > 0.05). In test group, the mPAP was (20.06 +/- 3.40) mm Hg (1 mm Hg = 0.133 kPa), mRVP was (22.53 +/- 2.53) mm Hg, WT% was (30.8 +/- 3.5)%, which were significantly lower than those in model group (P < 0.05), but higher than those in control group and test control group (P < 0.05).</p><p><b>CONCLUSION</b>The recombinant adenovirus could successfully carry p21 and transfect the lung tissue of PAH rat model, and full expression of p21. p21 gene could inhibit the development of PAH.</p>

Involvement of multiple signaling pathways in diallyl sulfide mediated apoptosis in mouse skin tumors.

Many chemopreventive agents appear to target signaling intermediates in apoptosis-inducing pathways. Inherently, the process of neoplastic conversion selects against apoptosis to initiate, promote, and perpetuate the malignant phenotype. Thus, targeting apoptosis pathways in pre-malignant cells, in which these pathways are still relatively intact, may be an effective module of cancer prevention. Diallyl sulfide (DAS), a naturally occurring organosulfide, present in garlic, is reported to have pleiotropic biological effects. DAS is known to inhibit chemically induced tumors in a number of in vivo and in vitro studies. The aberration of tumor suppressor gene, p53 and the ras oncogene have been linked to the induction of multiple signaling pathways and to the resistance offered by cancer cells to the apoptosis. Therefore, the present study was carried out to investigate the role of DAS on modulation of multiple p53 and ras-induced signaling pathways in 7,12-dimethylbenathacene (DMBA) induced skin carcinogenesis. The results showed that DAS up regulates expression of tumor suppressor protein p53 (wt p53) and its downstream target molecule p21/waf1. Proapoptotic protein, bax was upregulated by DAS supplementation. An opposite trend was observed in DMBA induced antiapoptotic proteins expressions, survivin and bcl-2, which were significantly downregulated by DAS supplementation. In the present study we also demonstrated that DAS supplementation significantly reduces the expression of ras oncoprotein and to modulate expression of its signaling molecules including PI3K/Akt and MAPKs. Western blot analysis demonstrated that DAS significantly reduced the DMBA induced protein expressions of PI3K/Akt and p38MAPK. However, DAS supplementation did not alter the expression JNK1 and ERK1/2. Thus, our results confirm that DAS can adopt a multi-prong strategy to target multiple signaling pathways leading to induction of apoptosis and inhibition of growth of DMBA induced skin tumors in Swiss albino mice. Although studies of single pathways have been helpful in guiding investigations, new tools to study the integration and multiplicity of signaling pathways hold the hope of improved understanding of the signaling pathway alterations in cancer chemoprevention by naturally occurring compounds.

The mouse ovarian surface epithelium cells (MOSE) transformation induced by c-myc/K-ras in / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the function of c-myc and K-ras in tumorigenesis of ovarian cancer.</p><p><b>METHODS</b>K-ras and/or c-myc cDNAs were introduced into mouse ovarian surface epithelium cells (MOSE) using recombinant Moloney retroviral vectors. The resulting MOSE cells were studied by cell proliferation assays, the ability to form colonies in soft agarose, matrigel invasion assays and tumorigenicity assays in nude mice.</p><p><b>RESULTS</b>K-ras and c-myc can be easily delivered to the normal MOSE cells by recombinant retroviruses. mRNA and protein of the target genes can be detected by RT-PCR and Western blot. Cell proliferation assays showed that MOSE-Ras cells and MOSE-RM cells (MOSE-Ras/Myc) grew more rapidly than parental cells (MOSE) and MOSE-Myc cells (P <0.01). In addtition, MOSE-RM cells grew more rapidly than MOSE-Ras cells (P <0. 05). Cell colony formation assays showed that while MOSE-Ras and MOSE-RM cells can form colonies in soft-agarose, the MOSE-Myc and MOSE cells did not. Matrigel invasion assays showed that MOSE-Ras and MOSE-RM cells have invasion ability, but not MOSE-Myc ascites and the control MOSE cells. Xenograft experiments showed that MOSE-Ras and MOSE-RM cells were able to form tumors in nude mice following intraperitoneal injection. Tumors were not observed in animals injected with either MOSE-Myc or MOSE cells.</p><p><b>CONCLUSION</b>The recombinant Moloney retroviral system is a highly efficient and convenient method for introducing and expressing foreign genes in murine surface epithelial cell cultures. In this model, expression of K-ras alone is sufficient to generate tumorigenic MOSE, however expression of c-myc in conjunction with K-ras results in cells with a higher index of malignancy. Based on the assays described in this report, expression of c-myc alone can not transform MOSE cultures although it does play a role in cooperation with K-ras.</p>

Current situation of researches on the molecule mechanism of hormone refractory prostate cancer / 中华男科学杂志

Most cases of prostate cancer become hormone refractory after 12 to 18 months of androgen deprivation therapy. The etiology of the disease is thought to be multifactorial, associated with genetic, dietary, and environmental factors. The article reviews the current situation of researches at home and abroad on the molecule mechanism of hormone refractory. It expounds the influence of the androgen receptor and its genetic mutation, apoptosis and the gene changes of p53, p21, EphB2 on prostate cancer. It is hoped to be of some directive value for the studies of prostate cancer.

Effect of mica granule on the expression of gene-protein associated with cancer in gastric mucosa tissue of chronic atrophic gastritis rats / 中国中药杂志

<p><b>OBJECTIVE</b>To research the regulative effect of mica monomer granule preparation on the expression of gene associated with cancer in gastric mucosa tissue of experimental chronic atrophic gastritis (CAG) rats.</p><p><b>METHOD</b>To treat experimental CAG rats using mica monomer granule preparation with three different dosage-high, moderate and low level respectively. To observe the expression changes of mutant antioncogene-p53 gene-protein, oncogene p21, antioncogene p16 and anti-apoptosis gene bcl-2 in gastric mucosa of CAG rats by two-step ways of EnVision system in immunohistochemical method.</p><p><b>RESULT</b>There was the tendency that mica monomer granule preparation with three different dosage could decrease the expression of p53 as well as p21, and mica had the obvious regulative effects on deletion of p16 and high-expression of bcl-2. It could also alleviate the inflammation of gastric mucosa and promote the regeneration of gland.</p><p><b>CONCLUSION</b>The treatment and reversion action of mica on chronic atrophic gastritis is probably related with the regulative effect on the expression of gene associated with cancer.</p>

Effect of buyang huanwu decoction drug serum on expression of p53 and p21 genes in cultured rat's cerebral cortical neuron after hypoxia in vitro / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the effect of Buyang Huanwu decoction (BHD) drug serum on rat's in vitro cultured cerebral cortical neuron apoptosis induced by hypoxia, and on the expression of p53 and p21 genes in hypoxia process.</p><p><b>METHODS</b>The model of hypoxia neuron apoptosis was established adopting Daniel method and treated with BHD drug serum. The neuron apoptosis rate was determined by flow cytometry with propidium iodide staining, the p53 and p21 gene expression was tested by immunohistochemical method with flow cytometry.</p><p><b>RESULTS</b>BHD could significantly inhibit the neuron apoptosis induced by hypoxia and down-regulate the expressions of p53 and p21 genes.</p><p><b>CONCLUSION</b>BHD shows inhibition on neuron hypoxia apoptosis and down-regulating of the p53 and p21 gene expression is one of its mechanisms.</p>

Canine biphasic synovial sarcoma: case report and immunohistochemical characterization

The clinical, radiological and pathologic features of a biphasic synovial sarcoma in the left elbow joint of a two-year-old male Rottweiler are presented. The tumor showed positive immunoreactivity for vimentin, Epithelial Membrane Antigen (EMA), p53 and PCNA, while it was negative for the cytokeratin used, S-100, Rb and p21. Immunohistochemistry for EMA allowed the identification of epithelioid components of synovial sarcoma, and may, therefore, contribute in establishing a diagnosis of biphasic synovial sarcoma. Intratumoral variation in PCNA immunoreactivity was minimal, indicating that the various tumor components proliferate at more or less similar rates. Overall, the characterized immunohistochemical profile for canine synovial sarcoma, not defined previously, may provide clues to the histogenesis of the phenotypically mesenchymal and epithelial elements of the tumor, and may be of value in the differential diagnosis of challenging cases, decreasing the risk of under- and mis-diagnosis. Although more cases need to be studied to determine whether there is a consistent pattern of immunostaining in canine synovial sarcoma, its potential significance is discussed in relation to the histogenesis, molecular pathology and differential diagnosis of canine synovial sarcoma.

Regresión de cáncer de mama después del tratamiento hormonal en un modelo murino / Mammary cancer regression after hormonal treatment in a murine model

Carcinomas mamarios murinos, originalmente inducidos por acetato de medroxiprogesterona, con crecimiento autónomo y receptores de estrógenos y progesterona regresionan con estradiol (E2) o con antiprogestágenos. Con el objeto de analizar los mecanismos de la regresión tumoral, estudiamos las características morfológicas y la participación de los reguladores del ciclo celular tales como p21, p27, p53 y MDM2 mediante inmunohistoquímica utilizando dos tumores sensibles al E2 o a los antiprogestágenos y uno sensible al E2 y antiprogestágenos resistente. La regresión se asocia a disminución del parénquima tumoral con aumento del estroma, a un efecto antiproliferativo y proapoptótico y a la inducción de proteínas inhibitorias del ciclo celular tales como p21 y p27. Sin embargo el patrón de expresión de los reguladores del ciclo celular varió. En los tumores sensibles a ambos tratamientos aumentó p21 y p27, los valores basales de p53 fueron altos y los de MDM2 bajos. En el tumor sensible sólo a E2 aumentó únicamente p27 y p21 permaneció en valores bajos acompañados por altos niveles basales de p53 y MDM2. Estos hallazgos sugieren que p21 podría ser esencial para la acción de los antiprogestágenos y que alteraciones en la vía p21/p53 podrían participar en la resistencia al tratamiento hormonal.

Research on expression and control of p16 and p21 by wild-type p53 gene in two lung adenocarcinoma cell lines / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To evaluate the potential of p53 gene therapy for lung cancer in nude mice.</p><p><b>METHODS</b>Two lung adenocarcinoma cell lines L-18 and 95D were infected with adenovirus encoding wild-type p53 gene pAdCMV -p53 (Ad-p53 ) in vitro and in vivo. The antitumor effect of wild type p53 gene was assessed by cell growth curve, reverse transcriptase polymerase chain reaction (RT-PCR) analysis and TUNEL staining methods.</p><p><b>RESULTS</b>The p53-specific growth inhibition and apoptosis of tumor cells were observed in both cell lines in vitro. By RT-PCR analysis, the increasing expression of p21 gene but not of p16 gene after p53 gene infection suggested that p21 gene played an important role in p53 gene induced cell apoptosis. The in vivo study revealed that celiac injection of p53 gene significantly inhibited the tumorigenesis in 95D and L-18 cells in nude mice. However, no obvious inhibition of tumorigenesis was observed after subcutaneous injection of p53 gene in L-18 cell line, compared with the inhibition noted in 95D cell line.</p><p><b>CONCLUSION</b>The results showed the adenovirus-mediated antitumor therapy by means of p53 gene infection might be a potential way to inhibit cancer growth and induce tumor cell apoptosis.</p>

Relevância clínica dos carcinomas de grande células pulmonares com relação às características neuroendócrinas, biomoleculares e estromais / Neuroendocrine and biologic features of primary tumors and tissue in pulmonary large cell carcinomas

Avaliou-se p21 e outros marcadores em espécimes cirúrgicos de 61 pacientes com carcinoma de grande células de pulmão. Utilizamos imunohistoquímica para avaliar a proteína p21 e a densidade de microvasos. A análise através do modelo multivariado de Cox mostrou que após o tratamento cirúrgico, o subtipo histológico foi significante com relação a sobrevida (p=0.02), mas a quantificação do tumor para o p21 e a densidade de microvasos adicionaram importante informação ao estudo do prognóstico e foram fatores mais fortemente relacionados com a sobrevida do que o subtipo histológico (P=0.00).We examined p21waf1/cip1 and other markers in tissue from 61 patients with surgically excised large cell carcinoma. We used immunohistochemistry and morphometry to evaluate the amount of tumor staining for p21waf1/cip1 and microvessel density. The study outcome was survival time until death from recurrent lung cancer. Multivariate Cox model analysis demonstrated that after surgical excision control, histologic subtypes were significantly related to survival time (P=0.02), but quantitative staining of the tumor for p21waf1/cip1 and microvessel density added prognostic information and were more strongly prognostic than histologic subtype (P=0.00)...

Importância de fatores celulares em associaçäo ao índice de prognóstico internacional na resposta ao tratamento inicial e na evoluçäo clínica de pacientes com linfoma difuso de grandes células B / Importance of cellular factors associated with international prognostic index on treatment response and clinical outcome in difuse large B-cell non-Hodgkin's lymphoma

Objetivos: O presente estudo teve os seguintes objetivos: 1) avaliar a aplicabilidade do índice de Prognóstico Internacional em uma população de pacientes com LDGCB; 2) correlacionar a expressão das proteínas P53, P21 e Mdm2 com a resposta ao tratamento inicial e evolução clínica de pacientes com LDGCB; 3) determinar a importância da expressão das proteínas Bcl-2 e Bcl-6 na resposta ao tratamento inicial e evolução clínica de pacientes com LDGCB; 4) detectar a presença de mutação nos exons 5 a 9 do gene p53 e correlacioná-la à resposta ao tratamento inicial e evolução clínica de pacientes com LDGCB; 5) detectar a presença do rearranjo bcl-2/IgH e correlacioná-la à resposta ao tratamento inicial e evolução clínica de pacientes com LDGCB. Métodos: Foram analisados, retrospectivamente, os 51 pacientes tratados no ambulatório de LNH do Hospital São Paulo (UNIFESP/EPM) com diagnóstico de LDGCB, no período de janeiro de 1990 a janeiro de 2002, e que apresentavam informações clínicas e blocos de parafina disponíveis para análise imunohistoquímica e molecular. A análise da expressão das proteínas P53, P21, Mdm2, Bcl-2 e Bcl-6 foi realizada por técnicas de imunohistoquímica. A pesquisa de mutação no gene p53 foi avaliada pelo método de PCR-SSCP, seguido de seqüenciamento automatizado das amostras contendo desvio de mobilidade (shift). A pesquisa do rearranjo bcl-2/IgH foi realizada pelo método de PCR para a detecção do rearranjo na região MBR do gene bcl-2. Resultados: O IPI pôde ser aplicado a esta população de pacientes com LDGCB, confimando seu valor como marcador prognóstico na sobrevida geral (p = 0,029) e como fator preditivo de resposta à terapia inicial (p= 0,003). A expressão das proteínas P53 e P21 se correlacionou com a sobrevida geral, havendo melhor evolução para o grupo de pacientes com expressão de P53 >=10 por cento e P21 >=10 por cento e pior evolução para P53 >=10 por cento e P21 <10 por cento (p= 0,031). A expressão de Mdm2 apresentou tendência à associação com a expressão de P53...(au)

Carcinoma de la vesícula biliar: expresión de productos de los oncogenes C-MYC y RAS-P-21 / Carcinoma of gallblader: expression of products of C-MYC and RAS-P-21 oncogene

The expression of c-myc and p-ras-21 oncogenes was studied using an immunohistochemical method with monoclonal antibodies in 126 samples of gallbladder carcinoma (103 primary tumors and 23 metastatic lesions). Twenty five gallbladder samples without tumor evidence were used as controls. C-myc oncoprotein was positive in one control sample and p-ras-21 oncoprotein was negative in all. Among primary carcinomas c-myc was positive in 9 (9 per cent) and 4 (4 per cent); among metastatic carcinomas c-myc was positive in 6 (26 per cent, p=0.03 vs primary carcinoma) and p-ras-21 in 11 (48 per cent, p <0.001 vs primary carcinoma). There was a non significant association between c-myc and p-ras-21 expression and degree of histological differentiation and levelñ of tumoral infiltration. It is concliuded that c-myc and p-ras-21 oncoprotein expression is observed in less than 10 per cent of primary gallbladder carcinomas and that this expression is significantly higher in metastatic cells