RESUMEN
The homeodomain-leucine zipper (HD-Zip) gene family plays a pivotal role in plant development and stress responses. Nevertheless, a comprehensive characterization of the HD-Zip gene family in kiwifruit has been lacking. In this study, we have systematically identified 70 HD-Zip genes in the Actinidia chinensis (Ac) genome and 55 in the Actinidia eriantha (Ae) genome. These genes have been categorized into four subfamilies (HD-Zip I, II, III, and IV) through rigorous phylogenetic analysis. Analysis of synteny patterns and selection pressures has provided insights into how whole-genome duplication (WGD) or segmental may have contributed to the divergence in gene numbers between these two kiwifruit species, with duplicated gene pairs undergoing purifying selection. Furthermore, our study has unveiled tissue-specific expression patterns among kiwifruit HD-Zip genes, with some genes identified as key regulators of kiwifruit responses to bacterial canker disease and postharvest processes. These findings not only offer valuable insights into the evolutionary and functional characteristics of kiwifruit HD-Zips but also shed light on their potential roles in plant growth and development.
Asunto(s)
Actinidia , Proteínas de Homeodominio , Proteínas de Homeodominio/genética , Genoma de Planta , Filogenia , Actinidia/genética , Leucina Zippers/genética , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Perfilación de la Expresión GénicaRESUMEN
BACKGROUND: Elucidation of the regulatory mechanism of kiwifruit response to gray mold disease caused by Botrytis cinerea can provide the basis for its molecular breeding to impart resistance against this disease. In this study, 'Hongyang' kiwifruit served as the experimental material; the TOPLESS/TOPLESS-RELATED (TPL/TPR) co-repressor gene AcTPR2 was cloned into a pTRV2 vector (AcTPR2-TRV) and the virus-induced gene silencing technique was used to establish the functions of the AcTPR2 gene in kiwifruit resistance to Botrytis cinerea. RESULTS: Virus-induced silencing of AcTPR2 enhanced the susceptibility of kiwifruit to Botrytis cinerea. Defensive enzymes such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and phenylalanine ammonia-lyase (PAL) and endogenous phytohormones such as indole acetic acid (IAA), gibberellin (GA3), abscisic acid (ABA), and salicylic acid (SA) were detected. Kiwifruit activated these enzymes and endogenous phytohormones in response to pathogen-induced stress and injury. The expression levels of the IAA signaling genes-AcNIT, AcARF1, and AcARF2-were higher in the AcTPR2-TRV treatment group than in the control. The IAA levels were higher and the rot phenotype was more severe in AcTPR2-TRV kiwifruits than that in the control. These results suggested that AcTPR2 downregulation promotes expression of IAA and IAA signaling genes and accelerates postharvest kiwifruit senescence. Further, Botrytis cinerea dramatically upregulated AcTPR2, indicating that AcTPR2 augments kiwifruit defense against pathogens by downregulating the IAA and IAA signaling genes. CONCLUSIONS: The results of the present study could help clarify the regulatory mechanisms of disease resistance in kiwifruit and furnish genetic resources for molecular breeding of kiwifruit disease resistance.
Asunto(s)
Actinidia/genética , Botrytis/genética , Resistencia a la Enfermedad/genética , Enfermedades de las Plantas/genética , Proteínas de Plantas/genética , Ácido Abscísico/metabolismo , Actinidia/metabolismo , Actinidia/microbiología , Botrytis/fisiología , Catalasa/metabolismo , Frutas/genética , Frutas/metabolismo , Frutas/microbiología , Regulación Fúngica de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Interacciones Huésped-Patógeno/genética , Ácidos Indolacéticos/metabolismo , Peroxidasa/metabolismo , Fenilanina Amoníaco-Liasa/metabolismo , Enfermedades de las Plantas/microbiología , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Superóxido Dismutasa/metabolismoRESUMEN
The fast estimation of leaf area index (LAI) is significant for learning the crops growth, monitoring the disease and insect, and assessing the yield of crops. This study used the hyperspectral compact airborne spectrographic imager (CASI) data of Zhangye city, in Heihe River basin, on July 7, 2012, and extracted the spectral reflectance accurately. The potential of broadband and red-edge vegetation index for estimating the LAI of crops was comparatively investigated by combined with the field measured data. On this basis, the sensitive wavebands for estimating the LAI of crops were selected and two new spectral indexes (NDSI and RSI) were constructed, subsequently, the spatial distribution of LAI in study area was analyzed. The result showed that broadband vegetation index NDVI had good effect for estimating the LAI when the vegetation coverage is relatively lower, the R2 and RMSE of estimation model were 0. 52, 0. 45 (p<0. 01) , respectively. For red-edge vegetation index, CIred edge took the different crop types into account fully, thus it gained the same estimation accuracy with NDVI. NDSI(569.00, 654.80) and RSI(597.60, 654.80) were constructed by using waveband combination algorithm, which has superior estimation results than NDVI and CIred edge. The R2 of estimation model used NDSI(569.00, 654.80) was 0. 77(p<0. 000 1), it mainly used the wavebands near the green peak and red valley of vegetation spectrum. The spatial distribution map of LAI was made according to the functional relationship between the NDSI(569.00, 654.80) and LAI. After analyzing this map, the LAI values were lower in the northwest of study area, this indicated that more fertilizer should be increased in this area. This study can provide technical support for the agricultural administrative department to learn the growth of crops quickly and make a suitable fertilization strategy.
Asunto(s)
Productos Agrícolas , Hojas de la Planta , Análisis Espectral , Modelos Teóricos , Análisis de RegresiónRESUMEN
OBJECTIVE: To explore the risk factors of contrast-induced nephropathy (CIN) in patients after coronary artery intervention. METHODS: A total of 637 patients undergoing diagnostic coronary angiography or percutaneous coronary intervention were enrolled. They were divided into the CIN and non-CIN groups according to the changes in serum creatinine levels within 48 hours after coronary artery intervention. Then the relevant risk factors of CIN were analyzed. RESULTS: Among them, CIN occurred in 49 patients with an incidence of 7.7%. The patients with diabetes and renal insufficiency had higher incidence of CIN at 15.5% and 22.5% respectively. Logistic regression analysis showed that the risk factors of CIN included advanced age, smoking, diabetes, renal insufficiency, hypercholesterolemia and hyperuricemia. CONCLUSION: For the patients of coronary artery intervention, the major risk factors of CIN are advanced age, diabetes and renal insufficiency.
Asunto(s)
Medios de Contraste/efectos adversos , Angiografía Coronaria/efectos adversos , Enfermedades Renales/inducido químicamente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de RiesgoRESUMEN
Akt, a downstream mediator of phosphatidylinositol 3-kinase (PI3K), is a signal transduction protein that plays a central role in tumorigenesis. The tumor suppressor gene PTEN negatively regulates the PI3K/Akt signaling pathway. However, the roles of Akt and PTEN function in patients with non-small cell lung cancer (NSCLC) is not well established. To clarify roles of expression of phosphorylated Akt (p-Akt) and loss of PTEN expression in biological behavior and prognosis of NSCLC. Immunohistochemical staining was used to determine the expression of p-Akt and PTEN in 20 cases of normal lung tissues and 102 cases patients with NSCLC. All patients with NSCLC were followed from 3 to 60 months. The positive incidence of p-Akt expression and loss incidence of PTEN expression in NSCLC were 41.2% (42/102) and 46.1% (47/102), while negative of p-Akt expression (0%, 0/20) and positive of PTEN expression (100%, 20/20) in normal lung tissues. Overexpression of p-Akt and loss of PTEN expression were correlated to poor differentiation, lymph node involvement, distant metastasis and late stages. A significant negative correlation was observed between expression of p-Akt and PTEN (r = -0.425, P < 0.001). Patients with p-Akt positive expression (42/102) and loss of PTEN expression (47/102) showed significantly worse 5 years survival rate and median survival time than relevant those with p-Akt negative expression (14.29% versus 33.33%, 14 months versus 32 months, Log-rank test X(2) = 14.24, P < 0.001) and PTEN positive expression (10.64% versus 38.18%, 15 months versus 40 months, Log-rank test X(2) = 21.06, P < 0.001). A univariate analysis revealed that smoking, tumor size, lymph node involvement, distant metastasis, stage, p-Akt and loss of PTEN expression were significant correlative factors with prognosis. The result of multivariate Cox analysis showed that smoking, stage and loss of PTEN expression were independent prognosticators. p-Akt is overexpressed and accompanied by the loss of PTEN in clinical specimens of NSCLC. Both p-Akt and PTEN are concerned with invasion and metastasis of NSCLC. Loss of PTEN expression is an independent poor prognostic factor for patients with NSCLC.
Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/química , Neoplasias Pulmonares/química , Fosfohidrolasa PTEN/análisis , Proteínas Proto-Oncogénicas c-akt/análisis , Adulto , Anciano , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Pulmón/química , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Fosfatidilinositol 3-Quinasas/fisiología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosforilación , Pronóstico , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Tasa de SupervivenciaRESUMEN
Cellular response to estrogen is mediated both by estrogen receptor (ER) binding to estrogen response element (ERE) and by non-nuclear actions like activation of signal transducing pathways. The main aims are to study if PI3K/Akt signaling pathway can be activated by 17beta-estradiol (E2) via non-nuclear action and to investigate the relationship of the action of E2 and ER in endometrial cancer cells expressing with different status of ER. The levels of phosphorylated Akt (Ser473) (P-Akt) and total Akt were examined by western blot and Akt kinase activity was measured in cells after stimulation with 1 microM E2 at different time points. Inhibitory role of LY294002 on activation of Akt induced by E2 and its estrogen antagonist, ICI182780 were also tested. P-Akt/Akt was used as a measure of activation of Akt. We found that maximum P-Akt/Akt and Akt kinase activity took place at 30 min in Ishikawa cells and 15 min in HEC-1A cells and the activation persisted for at least 2 h after stimulation with 1 microM E2. The activation of Akt elicited gradually with increasing doses of E2. PI3K inhibitor, LY294002, stopped the activating Akt in a dose-dependent manner and 50 microM LY294002 completely blocked the activation of Akt induced by E2. ICI182780 could block the activation of PI3K/Akt in ER-positive Ishikawa cells but not in HEC-1A cells with poor-expressed ER. This study demonstrated that E2 is able to promptly activate PI3K/Akt signal pathway in Ishikawa cells in an ER-dependent manner and ER-independent in HEC-1A cells. Blockage of PI3K/Akt cascade may become a potential and effective way to control endometrial carcinoma, especially in ER-negative cancers, which show no response to endocrinal therapy.
Asunto(s)
Neoplasias Endometriales/enzimología , Estradiol/fisiología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores de Estrógenos/fisiología , Transducción de Señal/fisiología , Línea Celular Tumoral , Cromonas/farmacología , Activación Enzimática/efectos de los fármacos , Femenino , Humanos , Morfolinas/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proteínas Proto-Oncogénicas c-akt/genética , ARN Mensajero/biosíntesis , Receptores de Estrógenos/biosíntesisRESUMEN
Chlorogenic acid (CGA), abundant in coffee and particular fruits, can modulate hypertension and vascular dysfunction. Hypoxia-induced pulmonary artery smooth muscle cells (PASMCs) proliferation has been tightly linked to vascular remodeling in pulmonary arterial hypertension (PAH). Thus, the present study was designed to investigate the effect of CGA on hypoxia-induced proliferation in cultured rat PASMCs. The data showed that CGA potently inhibited PASMCs proliferation and DNA synthesis induced by hypoxia. These inhibitory effects were associated with G1 cell cycle arrest and down-regulation of cell cycle proteins. Treatment with CGA reduced hypoxia-induced hypoxia inducible factor 1α (HIF-1α) expression and trans-activation. Furthermore, hypoxia-evoked c-Src phosphorylation was inhibited by CGA. In vitro ELISA-based tyrosine kinase assay indicated that CGA was a direct inhibitor of c-Src. Moreover, CGA attenuated physical co-association of c-Src/Shc/Grb2 and ERK2 phosphorylation in PASMCs. These results suggest that CGA inhibits hypoxia-induced proliferation in PASMCs via regulating c-Src-mediated signaling pathway. In vivo investigation showed that chronic CGA treatment inhibits monocrotaline-induced PAH in rats. These findings presented here highlight the possible therapeutic use of CGA in hypoxia-related PAH.
Asunto(s)
Ácido Clorogénico/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Músculo Liso Vascular/citología , Inhibidores de Proteínas Quinasas/farmacología , Arteria Pulmonar/citología , Animales , Proteína Tirosina Quinasa CSK , Proteínas de Ciclo Celular/genética , Hipoxia de la Célula/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Ácido Clorogénico/uso terapéutico , ADN/biosíntesis , Regulación hacia Abajo/efectos de los fármacos , Fase G1/efectos de los fármacos , Proteína Adaptadora GRB2/metabolismo , Hipertensión Pulmonar/inducido químicamente , Hipertensión Pulmonar/tratamiento farmacológico , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Masculino , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Monocrotalina/efectos adversos , Músculo Liso Vascular/metabolismo , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/uso terapéutico , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Transcripción Genética/efectos de los fármacos , Activación Transcripcional/efectos de los fármacos , Familia-src Quinasas/antagonistas & inhibidores , Familia-src Quinasas/metabolismoRESUMEN
OBJECTIVE: To detect RET (REarranged during Transfection) protein by immunohistochemistry (IHC) in gastric cancer. STUDY DESIGN: A total of 210 samples were employed, of which 197 specimens were from 91 surgical pieces of gastric adenocarcinoma, comprising 91 tumoral, 91 nontumoral, and 15 intramucosal dysplastic samples. Another 13 gastric mucosae were from cancer-free patients. Two RET antibodies (clones Ret01 and 3F8) were used separately for IHC. RESULTS: Of the nontumoral samples from gastric cancers, 28 were positive (31%) with either antibody Ret01 or 3F8. The positive stains were often located in deep pyloric glands and associated with chronic inflammation patterns (p = 0.045). RET positivity correlated with phosphorylated epidermal growth factor receptor, which had been previously tested (p = 0.021). In tumoral samples RET was positive in 7 cases with antibody Ret01 (8%) and 9 cases with 3F8 (10%). In 15 intramucosal dysplastic samples RET was detected in 6 cases with antibody Ret01 and 8 cases with 3F8. There was an accordance between the IHC using antibodies Ret01 and 3F8 in tumoral, nontumoral, and intramucosal dysplastic samples (p = 0.500, 1.000, and 0.500). The 13 samples from cancer-free patients were always negative. CONCLUSION: Activation of RET proto-oncogene may be one of the molecular pathogeneses in gastric inflammatory and tumoral diseases.
Asunto(s)
Inmunohistoquímica , Proteínas Proto-Oncogénicas c-ret/aislamiento & purificación , Neoplasias Gástricas/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patología , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-ret/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologíaRESUMEN
The purpose of this study was to analyze the clinical outcomes of simultaneous modulated accelerated radiotherapy (SMART) in patients with nasopharyngeal carcinoma (NPC). A total of 97 patients who underwent SMART for NPC between August 2005 and November 2011 were evaluated. The prescribed dose was 69.9 Gy/30 fractions at 2.33 Gy/fraction to the primary gross tumor volume (PGTV) including the nasopharynx gross target volume and the positive neck lymph nodes, and 60 Gy/30 fraction at 2.0 Gy/fraction to the PCTV1; 54 Gy/30 fractions at 1.8 Gy/fraction was given to the PCTV2. Among 59 patients with local advanced disease, 31 patients received concurrent chemoradiotherapy (chemo-RT) with a regimen consisting of 135 mg/m(2) paclitaxel on Day 1 and 25 mg/m(2) cisplatin on Days 1-3. The median follow-up period was 42 months. The local control rate (LCR), distant metastases-free survival (DMFS) and overall survival (OS) rates were 93.3%, 90.3% and 91.6% at 3 years, and 87.6%, 87.9% and 85.7% at 5 years, respectively. There was no significant difference in outcome with respect to these three indicators for Stage III and IV disease treated with/without concurrent chemoradiotherapy (P > 0.05). Acute toxicities included Grade 3 mucositis, skin desquamation, and leucopenia, which occurred in 78 (80.4%), 8 (8.2%), and 45 (46.4%) patients, respectively. No patient had a Grade 3-4 late toxicity. SMART was associated with a favorable outcome for NPC with acceptable toxicity. The local-regional control was excellent but distant metastasis remains the main risk. The combination of SMART and chemotherapy needs to be optimized through further studies to enhance outcomes for locally advanced diseases.
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Neoplasias Nasofaríngeas/radioterapia , Radioterapia de Intensidad Modulada/métodos , Adolescente , Adulto , Anciano , Carcinoma , Quimioradioterapia , Niño , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/tratamiento farmacológico , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada/efectos adversos , Adulto JovenRESUMEN
OBJECTIVE: To investigate the phosphorylation of epidermal growth factor receptor (EGFR) and its potentially associated chromosomal aberrations in gastric adenocarcinoma. METHODS: Phosphorylated EGFR (pEGFR) was detected by immunohistochemistry on 145 specimens including 60 tumoral, 60 non-tumoral, 12 tumor-adjacent intramucosal dysplasia from patients with gastric adenocarcinoma and 13 mucosae from cancer-free patients. EGFR gene amplification and chromosome 7 (Chr-7) polysomy were detected by fluorescence in situ hybridization. RESULTS: Positivity of pEGFR was found in 50 tumoral (83.3%) and 42 non-tumoral specimens (70.0%). There was an association between tumoral and non-tumoral zones on immunostains of pEGFR (r = 0.353, P = 0.006). Nuclear pEGFR usually presented in mucosae with Helicobacter pylori infection, stromal reaction or vascular invasion. Cytoplasmic pEGFR was correlated with local cancer extension (r = 0.337, P = 0.014) and inversely related with gastrokine 2, which had been previously detected in the same specimens. Eleven intramucosal dysplastic specimens were also positive for pEGFR while 13 mucosae from cancer-free patients were all negative. No EGFR gene amplification was observed. However, seven tumor specimens showed Chr-7 polysomy (11.7%) in which 5 were strongly positive for pEGFR. CONCLUSIONS: EGFR phosphorylation may be one of the mechanisms that promote tumor initiation and expansion in gastric adenocarcinoma. Detection of pEGFR with analysis of its nuclear or cytoplasmic patterns could be clinicopathologically valuable. Chr-7 polysomy may partially contribute to EGFR activation in gastric adenocarcinoma, although its role does not predominate.
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Adenocarcinoma/metabolismo , Aberraciones Cromosómicas , Cromosomas Humanos Par 7/genética , Receptores ErbB/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patología , Anciano , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Proteínas Portadoras/metabolismo , Receptores ErbB/genética , Femenino , Amplificación de Genes , Humanos , Técnicas para Inmunoenzimas , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fosforilación , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologíaAsunto(s)
Inhibidor p27 de las Quinasas Dependientes de la Ciclina/antagonistas & inhibidores , Neoplasias Endometriales/tratamiento farmacológico , Estradiol/farmacología , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cromonas/farmacología , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/fisiología , Neoplasias Endometriales/patología , Femenino , Fase G1/efectos de los fármacos , Humanos , Péptidos y Proteínas de Señalización Intracelular/fisiología , Morfolinas/farmacología , Fosfatidilinositol 3-Quinasas/fisiología , Proteínas Proto-Oncogénicas c-akt/fisiología , Transducción de Señal/fisiologíaRESUMEN
UNLABELLED: ERas activation and GKN2 reduction in gastric cancer has raised some notices in recent years, while nuclear beta-catenin positivity is considered as a tumoral marker. In this study, we compared immunohistochemistry of beta-catenin, GKN2 and ERas on tumoral and non-tumoral mucosae of 50 gastric carcinomas and 13 gastric samples of cancer-free patients. Nuclear positivity of beta-catenin was strong in 31 non-tumoral mucosae (62%) and 29 tumoral mucosae (58%). It was absent in samples of cancer-free patients. There was a correlation between non-tumoral and tumoral zones for nuclear beta-catenin positivity (P=0.013). ERas was positive in 35 non-tumoral tissues (70%) and 31 tumoral tissues (62%) but negatvie in samples of cancer-free patients. It was weak and spotty in non-tumoral mucosae but strong and diffuse in tumors. Positivity of ERas was age-related (P=0.028). However it had background staining effect. GKN2 was expressed in 33 non-tumoral mucosae (66%) and 35 tumoral mucosae (70%). Though GKN2 staining was moderate to strong in non-tumoral tissues and was comparatively weaker in tumors, their difference was minimal and difficult to discern. CONCLUSIONS: Beta-catenin nuclear location could be considered as a paraneoplastic pattern which is considerably tumor-related. ERas may be a potential biomarker for gastric cancer, but advanced studies are wanted. GKN2 reduction is indiscernible by immunostaining.
Asunto(s)
Adenocarcinoma/metabolismo , Proteínas Portadoras/metabolismo , Células Madre Embrionarias/metabolismo , Proteína Oncogénica p21(ras)/metabolismo , Neoplasias Gástricas/metabolismo , beta Catenina/metabolismo , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Núcleo Celular/metabolismo , Núcleo Celular/patología , Células Madre Embrionarias/patología , Femenino , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patología , Humanos , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/patología , Análisis de Matrices TisularesRESUMEN
BACKGROUND: Many colorectal carcinomas are resistant to the growth inhibitory response of transforming growth factor-beta (TGF-beta) due to alterations of components along the TGF-beta signaling pathway. The aim of this study was to examine the expression of TGF-beta1, TbetaRII and Smad4 in human colorectal carcinoma and their relationships with cancer growth. METHODS: Immunohistochemistry and in situ hybridization were performed in 38 cases of colorectal carcinoma. RESULTS: Intense signal for TGF-beta1 protein and TGF-beta1 mRNA were found in 71.1% (27/38) and 77.8% (21/27) of colorectal carcinoma, respectively. Intensive TbetaRII mRNA were detected only in 40% (11/27) cancer tissues (p<0.05). 65.8% (25/38) of colorectal carcinoma displayed decreased expression in TbetaRII immunoreactivity staining (p<0.05). Smad4 protein and Smad4 mRNA were reduced in 63.2% (24/38) and 63% (17/27) of tumors, respectively. Smad4 expression was related to tumor differentiation and Duke's stage (p<0.05). Furthermore, TGF-beta1-positive tumors with lymph node metastasis preferentially had significant reduced Smad4 expression (p<0.05). CONCLUSIONS: Down-regulation of TbetaRII as well as the over-expression of TGF-beta1 play a possible role for the escape of colorectal carcinoma from TGF-beta-mediated growth inhibition. Reduced Smad4 is associated with malignancy and progression of colorectal carcinoma.