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1.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(1): 139-142, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38433644

RESUMO

Type Ⅳ hiatal hernia with a high risk usually presents sudden or suddenly worsening epigastric pain,vomiting,and dysphagia.It is not conducive to early diagnosis and treatment when symptoms are atypical.Type Ⅳ hiatal hernia with severe anemia is rare.This article reports an atypical case of type Ⅳ hiatal hernia with melena and severe anemia as the main manifestations,aiming to improve clinicians' identification of the atypical clinical presentations of type Ⅳ hiatal hernia.


Assuntos
Anemia , Hérnia Hiatal , Humanos , Hérnia Hiatal/complicações
3.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(1): 167-170, 2023 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-36861172

RESUMO

POEMS syndrome is a rare disease caused by monoclonal plasma cell proliferative disorder.The typical signs include peripheral neuropathy,organ enlargement,endocrine disease,M proteinemia,and skin changes.In clinical practice,the atypical,complex,and changeable clinical manifestations of this syndrome can easily lead to misdiagnosis and missed diagnosis.A case of POEMS syndrome with peripheral edema and ascites as the main manifestations is reported in this paper.


Assuntos
Ascite , Síndrome POEMS , Humanos , Ascite/diagnóstico , Ascite/etiologia , Síndrome POEMS/diagnóstico , Edema/diagnóstico , Pele
4.
J Gastroenterol Hepatol ; 37(11): 2060-2066, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36068945

RESUMO

BACKGROUND AND AIM: Considering the limitation of varying acid suppression of proton pump inhibitors, this study was aimed to assess the efficacy, safety, and dose-effect relationship of keverprazan, a novel potassium-competitive acid blocker, in the treatment of duodenal ulcer (DU) compared with lansoprazole. METHODS: A randomized, double-blind, double-dummy, multicenter, low-dose, high-dose, and positive-drug parallel-controlled study was conducted to verify the non-inferiority of keverprazan (20 or 30 mg) to lansoprazole of 30 mg once daily for 4 to 6 weeks and dose-effect relationship of keverprazan in the treatment of patients with active DU confirmed by endoscopy. RESULTS: Of the 180 subjects randomized, including 55 cases in the keverprazan_20 mg group, 61 cases in the keverprazan_30 mg group, and 64 cases in the lansoprazole_30 mg group, 168 subjects (93.33%) completed the study. The proportions of healed DU subjects in the keverprazan_20 mg, keverprazan_30 mg, and lansoprazole_30 mg groups were respectively 87.27%, 90.16%, and 79.69% at week 4 (P = 0.4595) and were respectively 96.36%, 98.36%, and 92.19% at week 6 (P = 0.2577). The incidence of adverse events in the keverprazan_20 mg group was lower than that in the lansoprazole_30 mg (P = 0.0285) and keverprazan_30 mg groups (P = 0.0398). CONCLUSIONS: Keverprazan was effective and non-inferior to lansoprazole in healing DU. Based on the comparable efficacy and safety data, keverprazan of 20 mg once daily is recommended for the follow-up study of acid-related disorders. (Trial registration number: ChiCTR2100043455.).


Assuntos
Antiulcerosos , Úlcera Duodenal , Humanos , Úlcera Duodenal/tratamento farmacológico , Úlcera Duodenal/induzido quimicamente , Antiulcerosos/uso terapêutico , Seguimentos , Lansoprazol/efeitos adversos , Inibidores da Bomba de Prótons/efeitos adversos , Método Duplo-Cego , 2-Piridinilmetilsulfinilbenzimidazóis/efeitos adversos
6.
Genes Dis ; 8(6): 814-826, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34522710

RESUMO

Intestinal cancers are developed from intestinal epithelial stem cells (ISCs) in intestinal crypts through a multi-step process involved in genetic mutations of oncogenes and tumor suppressor genes. ISCs play a key role in maintaining the homeostasis of gut epithelium. In 2009, Sato et al established a three-dimensional culture system, which mimicked the niche microenvironment by employing the niche factors, and successfully grew crypt ISCs into organoids or Mini-guts in vitro. Since then, the intestinal organoid technology has been used to delineate cellular signaling in ISC biology. However, the cultured organoids consist of heterogeneous cell populations, and it was technically challenging to introduce genomic changes into three-dimensional organoids. Thus, there was a technical necessity to develop a two-dimensional ISC culture system for effective genomic manipulations. In this study, we established a conditionally immortalized mouse intestinal crypt (ciMIC) cell line by using a piggyBac transposon-based SV40 T antigen expression system. We showed that the ciMICs maintained long-term proliferative activity under two-dimensional niche factor-containing culture condition, retained the biological characteristics of intestinal epithelial stem cells, and could form intestinal organoids in three-dimensional culture. While in vivo cell implantation tests indicated that the ciMICs were non-tumorigenic, the ciMICs overexpressing oncogenic ß-catenin and/or KRAS exhibited high proliferative activity and developed intestinal adenoma-like pathological features in vivo. Collectively, these findings strongly suggested that the engineered ciMICs should be used as a valuable tool cell line to dissect the genetic and/or epigenetic underpinnings of intestinal tumorigenesis.

7.
Sheng Li Xue Bao ; 69(4): 509-514, 2017 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-28825110

RESUMO

Potassium channels have multitudinous subtypes, which are widely distributed on cell membranes. They affect various cellular physiological functions through participating in processes such as resting potential formation, substance transportation, enzyme activity and cellular communication. Autophagy is a significant mechanism to maintain intracellular metabolic homeostasis. The abnormity of autophagy may lead to the occurrence and development of multiple diseases. Recently, it has been reported that K+ channels and cell autophagy are closely related. Here, we reviewed the recent research progresses on regulation of autophagy signaling, autophagy flux or autophagolysosome formation by K+ channel, and discussed the physiological significance of autophagy regulation by K+ channel.


Assuntos
Autofagia , Canais de Potássio/fisiologia , Transdução de Sinais , Animais , Homeostase , Humanos , Fagossomos
8.
Sheng Li Xue Bao ; 69(3): 252-260, 2017 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-28638916

RESUMO

To study the correlation between the spatial cognitive impairment and different subtypes of estrogen receptor α (ERα) of hippocampus in diabetic mice, we used alloxan (intraperitoneal injection) to induce type 1 diabetes in male Kunming mice and compared the spatial cognitive ability of the model mice with that of control mice through Morris water maze test. Meanwhile, using Western blot, we detected the protein expressions of ER-α36, ER-α66, caveolin-1, PKCα, cAMP-response element binding protein 2 (CREB2), and synaptophysin (Syn) in the hippocampus of the mice. The results showed that on the 3rd and 5th days of training, the ability of spatial learning and memory in the diabetic mice was significantly inferior to that of the control mice (P < 0.05). In the diabetic mice, the protein expressions of caveolin-1 and PKCα were decreased (P < 0.05), but ER-α66 expression was unaffected, while ER-α36 and CREB2 expressions were significantly increased (P < 0.05) compared with those of the control mice. The results suggest that abnormal expression of ER-α36 and related signal molecules may be important factors for diabetes-induced spatial cognitive impairment.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus Experimental/fisiopatologia , Receptor alfa de Estrogênio/metabolismo , Hipocampo/fisiopatologia , Memória , Animais , Caveolina 1/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Hipocampo/metabolismo , Masculino , Aprendizagem em Labirinto , Camundongos , Proteína Quinase C-alfa/metabolismo , Sinaptofisina/metabolismo
9.
Microsc Res Tech ; 78(8): 688-96, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26031767

RESUMO

INTRODUCTION: Here we co-cultured hepatic progenitor cells (HPCs) and mesenchymal stem cells (MSCs) to investigate whether the co-culture environments could increase hepatocytes form. METHODS: Three-dimensional (3D) co-culture model of HPCs and MSCs was developed and morphological features of cells were continuously observed. Hepatocyte specific markers Pou5f1/Oct4, AFP, CK-18 and Alb were analyzed to confirm the differentiation of HPCs. The mRNA expression of CK-18 and Alb was analyzed by RT-PCR to investigate the influence of co-culture model to the terminal differentiation process of mature hepatocytes. The functional properties of hepatocyte-like cells were detected by continuously monitoring the albumin secretion using Gaussia luciferase assays. Scaffolds with HPCs and MSCs were implanted into nude mouse subcutaneously to set up the in vivo co-culture model. RESULTS: Although two groups formed smooth spheroids and high expressed of CK-18 and Alb, hybrid spheroids had more regular structures and higher cell density. CK-18 and Alb mRNA were at a relatively higher expression level in co-culture system during the whole cultivation time (P < 0.05). Albumin secretion rates in the hybrid spheroids had been consistently higher than that in the mono-culture spheroids (P < 0.05). In vivo, the hepatocyte-like cells were consistent with the morphological features of mature hepatocytes and more well-differentiated hepatocyte-like cells were observed in the co-culture group. CONCLUSIONS: HPCs and MSCs co-culture system is an efficient way to form well-differentiated hepatocyte-like cells, hence, may be helpful to the cell therapy of hepatic tissues and alleviate the problem of hepatocytes shortage.


Assuntos
Técnicas de Cocultura/métodos , Hepatócitos/citologia , Células-Tronco Mesenquimais/citologia , Animais , Materiais Biocompatíveis , Diferenciação Celular , Linhagem Celular , Hepatócitos/transplante , Imuno-Histoquímica , Transplante de Células-Tronco Mesenquimais , Camundongos , Camundongos Nus , Tecidos Suporte
10.
Cell Physiol Biochem ; 34(4): 1318-38, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25301359

RESUMO

BACKGROUND/AIMS: Liver is a vital organ and retains its regeneration capability throughout adulthood, which requires contributions from different cell populations, including liver precursors and intrahepatic stem cells. To overcome the mortality of hepatic progenitors (iHPs) in vitro, we aim to establish reversibly immortalized hepatic progenitor cells from mouse embryonic liver. METHODS AND RESULTS: Using retroviral system to stably express SV40 T antigen flanked with Cre/LoxP sites, we establish a repertoire of iHP clones with varied differentiation potential. The iHP cells maintain long-term proliferative activity and express varied levels of progenitor markers (Pou5f1/Oct4 and Dlk) and hepatocyte markers (AFP, Alb and ApoB). Five representative iHP clones express hepatic/pancreatic transcription factors HNF3α/Foxa1, HNF3ß/Foxa2, and HNF4α/MODY1. Dexamethasone is shown to promote the expression of hepatocyte markers AFP and TAT, along with ICG-uptake and glycogen storage functions in the iHP clones. Cre-mediated removal of SV40 T antigen reverses the proliferative activity of iHP cells. When iHP cells are subcutaneously implanted in athymic nude mice, no tumor formation is observed for up to 8 weeks. CONCLUSIONS: We demonstrate that the established iHP cells are stable, reversible, and non-tumorigenic hepatic progenitor-like cells, which should be valuable for studying liver organogenesis, metabolic regulations, and hepatic lineage-specific differentiation.


Assuntos
Células-Tronco Embrionárias/fisiologia , Hepatócitos/fisiologia , Fígado/fisiologia , Células-Tronco/citologia , Animais , Biomarcadores/metabolismo , Diferenciação Celular/fisiologia , Linhagem Celular , Proliferação de Células/fisiologia , Células-Tronco Embrionárias/metabolismo , Feminino , Glicogênio/metabolismo , Células HEK293 , Humanos , Fígado/metabolismo , Camundongos , Camundongos Nus , Células-Tronco/metabolismo
11.
Oncol Rep ; 32(3): 1013-20, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24993644

RESUMO

Colorectal cancer (CRC) is one of the most deadly cancers worldwide. Significant progress has been made in understanding the molecular pathogenesis of CRC, which has led to successful early diagnosis, surgical intervention and combination chemotherapy. However, limited therapeutic options are available for metastatic and/or drug-resistant CRC. While the aberrantly activated Wnt/ß-catenin pathway plays a critical initiating role in CRC development, disruption of the bone morphogenetic protein (BMP) pathway causes juvenile polyposis syndrome, suggesting that BMP signaling may play a role in CRC development. However, conflicting results have been reported concerning the possible roles of BMP signaling in sporadic colon cancer. Here, we investigated the effect of BMP2 on the proliferation, migration, invasiveness and tumor growth capability of human CRC cells. Using an adenovirus vector that overexpresses BMP2 and the piggyBac transposon-mediated stable BMP2 overexpression CRC line, we found that exogenous BMP2 effectively inhibited HCT116 cell proliferation and colony formation. BMP2 was shown to suppress colon cancer cell migration and invasiveness. Under a low serum culture condition, forced expression of BMP2 induced a significantly increased level of apoptosis in HCT116 cells. Using a xenograft tumor model, we found that forced expression of BMP2 in HCT116 cells suppressed tumor growth, accompanied by decreased cell proliferation activity. Taken together, our results strongly suggest that BMP2 plays an important inhibitory role in governing the proliferation and aggressive features of human CRC cells.


Assuntos
Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 2/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Vetores Genéticos/administração & dosagem , Animais , Apoptose , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/metabolismo , Dependovirus/genética , Terapia Genética , Células HCT116 , Células HEK293 , Humanos , Camundongos , Camundongos Nus , Invasividade Neoplásica , Transplante de Neoplasias
12.
Clin Endosc ; 47(3): 266-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24944993

RESUMO

A patient with acute obscure gastrointestinal bleeding was found to have a large amount of food retention in the stomach after fasting for >12 hours. We tried to adjust the patient's body position to facilitate capsule endoscopic examination. The patient laid on the bed on his right side, which is the position required for a normal procedure, and then his hip was raised while his upper body was lowered gradually until the pylorus appeared at the center of the screen of the real-time monitor. It took 15 minutes of body position adjustment to make the pylorus appear at the center of the monitor and another 5 minutes for the capsule endoscope to enter the duodenum. The lesion was ultimately found at the terminal small intestine.

13.
PLoS One ; 9(4): e93608, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24695466

RESUMO

Three-dimensional organoids have been recently established from various tissue-specific progenitors (such as intestinal stem cells), induced pluripotent stem cells, or embryonic stem cells. These cultured self-sustaining stem cell-based organoids may become valuable systems to study the roles of tissue-specific stem cells in tissue genesis and disease development. It is thus conceivable that effective genetic manipulations in such organoids may allow us to reconstruct disease processes and/or develop novel therapeutics. Recombinant adenoviruses are one of the most commonly used viral vectors for in vitro and in vivo gene deliveries. In this study, we investigate if adenoviruses can be used to effectively deliver transgenes into the cultured "mini-gut" organoids derived from intestinal stem cells. Using adenoviral vectors that express fluorescent proteins, we demonstrate that adenoviruses can effectively deliver transgenes into the cultured 3-D "mini-gut" organoids. The transgene expression can last at least 10 days in the cultured organoids. As a proof-of-principle experiment, we demonstrate that adenovirus-mediated noggin expression effectively support the survival and self-renewal of mini-gut organoids, while adenovirus-mediated expression of BMP4 inhibits the self-sustainability and proliferation of the organoids. Thus, our results strongly suggest that adenovirus vectors can be explored as effective gene delivery vehicles to introduce genetic manipulations in 3-D organoids.


Assuntos
Adenoviridae/genética , Técnicas de Transferência de Genes , Vetores Genéticos , Intestinos/citologia , Animais , Meios de Cultivo Condicionados , Células HEK293 , Humanos , Camundongos
14.
J Biomed Mater Res A ; 102(4): 1017-25, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23625886

RESUMO

Decellularized whole organs represent ideal scaffolds for engineering new organs and/or cell transplantation. Here, we investigate whether decellularized liver scaffolds provide cell-friendly biocompatible three-dimensional (3-D) environment to support the proliferation and differentiation of hepatic progenitor cells. Mouse liver tissues are efficiently decellularized through portal vein perfusion. Using the reversibly immortalized mouse fetal hepatic progenitor cells (iHPCs), we are able to effectively recellularize the decellularized liver scaffolds. The perfused iHPCs survive and proliferate in the 3-D scaffolds in vitro for 2 weeks. When the recellularized scaffolds are implanted into the kidney capsule of athymic nude mice, cell survival and proliferation of the implanted scaffolds are readily detected by whole body imaging for 10 days. Furthermore, epidermal growth factor (EGF) is shown to significantly promote the proliferation and differentiation of the implanted iHPCs. Histologic and immunochemical analyzes indicate that iHPCs are able to proliferate and differentiate to mature hepatocytes upon EGF stimulation in the scaffolds. The recellularization of the biomaterial scaffolds is accompanied with vascularization. Taken together, these results indicate that decullarized liver scaffolds effectively support the proliferation and differentiation of iHPCs, suggesting that decellularized liver matrix may be used as ideal biocompatible scaffolds for hepatocyte transplantation.


Assuntos
Diferenciação Celular , Feto/citologia , Hepatócitos/citologia , Fígado/citologia , Células-Tronco/citologia , Tecidos Suporte/química , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Transformada , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Células HEK293 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Perfusão , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Ensaio de Cápsula Sub-Renal
15.
Oncol Rep ; 30(1): 292-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23633038

RESUMO

Plant-derived active constituents and their semi-synthetic or synthetic analogs have served as major sources of anticancer drugs. 20(S)-protopanaxadiol (PPD) is a metabolite of ginseng saponin of both American ginseng (Panax quinquefolius L.) and Asian ginseng (Panax ginseng C.A. Meyer). We previously demonstrated that ginsenoside Rg3, a glucoside precursor of PPD, exhibits anti-proliferative effects on HCT116 cells and reduces tumor size in a xenograft model. Our subsequent study indicated that PPD has more potent antitumor activity than that of Rg3 in vitro although the mechanism underlying the anticancer activity of PPD remains to be defined. Here, we investigated the mechanism underlying the anticancer activity of PPD in human cancer cells in vitro and in vivo. PPD was shown to inhibit growth and induce cell cycle arrest in HCT116 cells. The in vivo studies indicate that PPD inhibits xenograft tumor growth in athymic nude mice bearing HCT116 cells. The xenograft tumor size was significantly reduced when the animals were treated with PPD (30 mg/kg body weight) for 3 weeks. When the expression of previously identified Rg3 targets, A kinase (PRKA) anchor protein 8 (AKAP8L) and phosphatidylinositol transfer protein α (PITPNA), was analyzed, PPD was shown to inhibit the expression of PITPNA while upregulating AKAP8L expression in HCT116 cells. Pathway-specific reporter assays indicated that PPD effectively suppressed the NF-κB, JNK and MAPK/ERK signaling pathways. Taken together, our results suggest that the anticancer activity of PPD in colon cancer cells may be mediated through targeting NF-κB, JNK and MAPK/ERK signaling pathways, although the detailed mechanisms underlying the anticancer mode of PPD action need to be fully elucidated.


Assuntos
Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Sapogeninas/farmacologia , Sapogeninas/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteínas de Ligação a DNA/biossíntese , MAP Quinases Reguladas por Sinal Extracelular/biossíntese , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Xenoenxertos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Proteínas Quinases JNK Ativadas por Mitógeno/biossíntese , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Camundongos Nus , NF-kappa B/biossíntese , NF-kappa B/metabolismo , Transplante de Neoplasias , Proteínas Nucleares/biossíntese , Panax , Proteínas de Transferência de Fosfolipídeos/biossíntese , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Transdução de Sinais/efeitos dos fármacos
16.
Int J Oncol ; 38(2): 437-45, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21152855

RESUMO

Colorectal cancer (CRC) is one of the most common and deadly malignancies in the world. Most CRCs are initiated by aberrant activation of the Wnt/ß-catenin signaling pathway. Despite the advances in its early diagnosis, optimized surgical approaches, and chemotherapies, the clinical management of advanced CRC requires effective adjuvant agents. Ginsenoside Rg3 is a single compound isolated from American ginseng (Panax quinquefolius L., Araliaceae) and Asian ginseng (Panax ginseng C. A. Meyer). We investigated the anticancer activity of Rg3 on colon cancer cells and its potential molecular mechanism behind Rg3's anticancer activity. We found that Rg3 inhibits cell proliferation and viability of cancer cells in vitro. This inhibitory effect of Rg3 is, at least in part, mediated by blocking nuclear translocation of the ß-catenin protein and hence inhibiting ß-catenin/Tcf transcriptional activity. Allelic deletion of the oncogenic ß-catenin in HCT116 cells renders the cells more sensitive to Rg3-induced growth inhibition. Using the xenograft tumor model of human colon cancer, we have demonstrated that Rg3 effectively inhibits the growth of tumors derived from the human colon cancer cell line HCT116. Histologic examination revealed that Rg3 inhibits cancer cell proliferation, decreases PNCA expression and diminishes nuclear staining intensity of ß-catenin. Taken together, our results strongly suggest that the anticancer activity of Rg3 may be in part caused by blocking the nuclear translocation of ß-catenin in colon cancer cells. This line of investigation may lead to the development of novel therapies in which Rg3 can be used as an effective adjuvant agent for the clinical management of colorectal cancers.


Assuntos
Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ginsenosídeos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Western Blotting , Ensaio de Unidades Formadoras de Colônias , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Regulação para Baixo , Feminino , Imunofluorescência , Humanos , Técnicas Imunoenzimáticas , Luciferases/metabolismo , Camundongos , Camundongos Nus , Panax , Células Tumorais Cultivadas
17.
Mol Pharmacol ; 79(2): 211-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20978119

RESUMO

As one of the most common malignancies, colon cancer is initiated by abnormal activation of the Wnt/ß-catenin pathway. Although the treatment options have increased for some patients, overall progress has been modest. Thus, there is a great need to develop new treatments. We have found that bisbenzylisoquinoline alkaloid tetrandrine (TET) exhibits anticancer activity. TET is used as a calcium channel blocker to treat hypertensive and arrhythmic conditions in Chinese medicine. Here, we investigate the molecular basis underlying TET's anticancer activity. We compare TET with six chemotherapy drugs in eight cancer lines and find that TET exhibits comparable anticancer activities with camptothecin, vincristine, paclitaxel, and doxorubicin, and better than that of 5-fluorouracil (5-FU) and carboplatin. TET IC50 is ≤5 µM in most of the tested cancer lines. TET exhibits synergistic anticancer activity with 5-FU and reduces migration and invasion capabilities of HCT116 cells. Furthermore, TET induces apoptosis and inhibits xenograft tumor growth of colon cancer. TET treatment leads to a decrease in ß-catenin protein level in xenograft tumors, which is confirmed by T-cell factor/lymphocyte enhancer factor and c-Myc reporter assays. It is noteworthy that HCT116 cells with allelic oncogenic ß-catenin deleted are less sensitive to TET-mediated inhibition of proliferation, viability, and xenograft tumor growth. Thus, our findings strongly suggest that the anticancer effect of TET in colon cancer may be at least in part mediated by targeting ß-catenin activity. Therefore, TET may be used alone or in combination as an effective anticancer agent.


Assuntos
Benzilisoquinolinas/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/patologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Wnt/antagonistas & inibidores , beta Catenina/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Camundongos , Transplante Heterólogo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
18.
Curr Mol Pharmacol ; 4(1): 14-25, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20825362

RESUMO

The Wnt pathway plays a critical role in development and differentiation of many tissues, such as the gut, hair follicles, and bone. Increasing evidence indicates that Wnts may function as key regulators in osteogenic differentiation of mesenchymal stem cells and bone formation. Conversely, aberrant Wnt signaling is associated with many osteogenic pathologies. For example, genetic alterations in the Wnt signaling pathway lead to osteoporosis and osteopenia, while inactivating mutations of Wnt inhibitors result in a hyperostotic skeleton with increased bone mineral density. Hyperparathyroidism causes osteopenia via induction of the Wnt signaling pathway. Lithium, often used to treat bipolar disorder, blocks a Wnt antagonist, decreasing the patient's risk of fractures. Thus, manipulating the Wnt pathway may offer plenty therapeutic opportunities in treating bone disorders. In fact, induction of the Wnt signaling pathway or inhibition of Wnt antagonists has shown promise in treating bone metabolic disorders, including osteoporosis. For example, antibodies targeting the Wnt inhibitor Sclerostin lead to increased bone mineral density in post-menopausal women. However, such therapies targeting the Wnt pathway are not without risk, as genetic alternations may lead to over-activation of Wnt/ß-catenin and its association with many tumors. It is conceivable that targeting Wnt inhibitors may predispose the individuals to tumorigenic phenotypes, at least in bone. Here, we review the roles of Wnt signaling in bone metabolic and pathologic processes, as well as the therapeutic potential for targeting Wnt pathway and its associated risks in bone diseases.


Assuntos
Doenças Ósseas/terapia , Proteínas Wnt/antagonistas & inibidores , Doenças Ósseas/patologia , Humanos , Células-Tronco Mesenquimais/citologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Wnt/metabolismo , Proteínas Wnt/fisiologia
19.
PLoS One ; 5(7): e11917, 2010 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-20689834

RESUMO

BACKGROUND: As one of the least studied bone morphogenetic proteins (BMPs), BMP9 is one of the most osteogenic BMPs. Retinoic acid (RA) signaling is known to play an important role in development, differentiation and bone metabolism. In this study, we investigate the effect of RA signaling on BMP9-induced osteogenic differentiation of mesenchymal progenitor cells (MPCs). METHODOLOGY/PRINCIPAL FINDINGS: Both primary MPCs and MPC line are used for BMP9 and RA stimulation. Recombinant adenoviruses are used to deliver BMP9, RARalpha and RXRalpha into MPCs. The in vitro osteogenic differentiation is monitored by determining the early and late osteogenic markers and matrix mineralization. Mouse perinatal limb explants and in vivo MPC implantation experiments are carried out to assess bone formation. We find that both 9CRA and ATRA effectively induce early osteogenic marker, such as alkaline phosphatase (ALP), and late osteogenic markers, such as osteopontin (OPN) and osteocalcin (OC). BMP9-induced osteogenic differentiation and mineralization is synergistically enhanced by 9CRA and ATRA in vitro. 9CRA and ATRA are shown to induce BMP9 expression and activate BMPR Smad-mediated transcription activity. Using mouse perinatal limb explants, we find that BMP9 and RAs act together to promote the expansion of hypertrophic chondrocyte zone at growth plate. Progenitor cell implantation studies reveal that co-expression of BMP9 and RXRalpha or RARalpha significantly increases trabecular bone and osteoid matrix formation. CONCLUSION/SIGNIFICANCE: Our results strongly suggest that retinoid signaling may synergize with BMP9 activity in promoting osteogenic differentiation of MPCs. This knowledge should expand our understanding about how BMP9 cross-talks with other signaling pathways. Furthermore, a combination of BMP9 and retinoic acid (or its agonists) may be explored as effective bone regeneration therapeutics to treat large segmental bony defects, non-union fracture, and/or osteoporotic fracture.


Assuntos
Fator 2 de Diferenciação de Crescimento/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Tretinoína/farmacologia , Animais , Western Blotting , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular , Células Cultivadas , Fator 2 de Diferenciação de Crescimento/genética , Humanos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Técnicas de Cultura de Órgãos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , Receptor alfa de Ácido Retinoico , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
J Biol Chem ; 285(38): 29588-98, 2010 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-20628059

RESUMO

Mesenchymal stem cells (MSCs) are bone marrow stromal cells that can differentiate into multiple lineages. We previously demonstrated that BMP9 is one of the most potent BMPs to induce osteogenic differentiation of MSCs. BMP9 is one of the least studied BMPs. Whereas ALK1, ALK5, and/or endoglin have recently been reported as potential BMP9 type I receptors in endothelial cells, little is known about type I receptor involvement in BMP9-induced osteogenic differentiation in MSCs. Here, we conduct a comprehensive analysis of the functional role of seven type I receptors in BMP9-induced osteogenic signaling in MSCs. We have found that most of the seven type I receptors are expressed in MSCs. However, using dominant-negative mutants for the seven type I receptors, we demonstrate that only ALK1 and ALK2 mutants effectively inhibit BMP9-induced osteogenic differentiation in vitro and ectopic ossification in MSC implantation assays. Protein fragment complementation assays demonstrate that ALK1 and ALK2 directly interact with BMP9. Likewise, RNAi silencing of ALK1 and ALK2 expression inhibits BMP9-induced BMPR-Smad activity and osteogenic differentiation in MSCs both in vitro and in vivo. Therefore, our results strongly suggest that ALK1 and ALK2 may play an important role in mediating BMP9-induced osteogenic differentiation. These findings should further aid us in understanding the molecular mechanism through which BMP9 regulates osteogenic differentiation of MSCs.


Assuntos
Receptores de Ativinas Tipo I/metabolismo , Fator 2 de Diferenciação de Crescimento/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteogênese/efeitos dos fármacos , Receptores de Ativinas Tipo I/genética , Receptores de Activinas Tipo II , Fosfatase Alcalina/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Ativação Enzimática/efeitos dos fármacos , Fator 2 de Diferenciação de Crescimento/genética , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Osteogênese/genética , Ligação Proteica , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Microtomografia por Raio-X
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