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Li M, Chan C, Chan C, Chan H, Hui L, Ziea E. P04.78. Development of an integrative service model for dysthymia patients with body-mind-spirit approach in Chinese medicine clinics in Hong Kong. Altern Ther Health Med 2012. [PMCID: PMC3373952 DOI: 10.1186/1472-6882-12-s1-p348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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102
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Mu W, Hui L. Establishing a cancer cell in the inflammatory tissue: an epigenetic circuit. Acta Biochim Biophys Sin (Shanghai) 2012; 44:279-80. [PMID: 22467139 DOI: 10.1093/abbs/gms021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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103
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Chau PH, Woo J, Lee CH, Cheung WL, Chen J, Chan WM, Hui L, McGhee SM. Older people with diabetes have higher risk of depression, cognitive and functional impairments: implications for diabetes services. J Nutr Health Aging 2011; 15:751-5. [PMID: 22089223 DOI: 10.1007/s12603-011-0071-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVES To examine the relationship between diabetes and impairments in functional and cognitive status as well as depression in older people. DESIGN Cross-sectional study. SETTING Elderly Health Centres (EHC) in Hong Kong. PARTICIPANTS 66,813 older people receiving baseline assessment at EHC in 1998 to 2001. MEASUREMENTS Diabetes status was defined by self-report and blood glucose tests. Functional status was assessed by 5 items of instrumental activities of daily living (IADL) and 7 items of activities of daily living (ADL). Cognitive status was screened by the Abbreviated Mental Test-Hong Kong version (AMT). Depressive symptoms were screened by the Geriatric Depression Scale-Chinese version (GDS). RESULTS Among the subjects, 10.4% reported having regular treatment for diabetes, 3.4% had diabetes but were not receiving regular treatment, and 86.2% did not have diabetes. After controlling for age, sex and education level, those having regular treatment for diabetes were 1.7 times more likely (OR=1.65, 95% CI: 1.51-1.80) to have functional impairment, 1.3 times more likely (OR=1.28, 95% CI: 1.11-1.48) to have cognitive impairment and 1.3 times more likely (OR=1.35, 95% CI: 1.25-1.46) to have depression, than older people without diabetes. CONCLUSION Older people with diabetes may be less capable of managing the disease than the younger ones as a result of increased risk of both physical and cognitive impairment. This study provided further evidence for the need of an international consensus statement regarding care of diabetes in older people.
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Hui L, Xiaomei G, Wei J, Chunxue B, Zhaochong Z. EGFR-TKI Therapy Prolongs Survival In Non-small Cell Lung Cancer Patients With Brain Metastases or Bone Metastases. Int J Radiat Oncol Biol Phys 2011. [DOI: 10.1016/j.ijrobp.2011.06.1853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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105
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Horak C, Hui L, Delmonte T, Han X, Ledeine J, Gustafson N, Lynch T, Khambata-Ford S. 9089 POSTER Exploratory Predictive Biomarker Assessment in the BMS099 Study of Cetuximab in NSCLC. Eur J Cancer 2011. [DOI: 10.1016/s0959-8049(11)72401-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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106
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Huang P, He Z, Ji S, Sun H, Xiang D, Liu C, Hu Y, Wang X, Hui L. Induction of functional hepatocyte-like cells from mouse fibroblasts by defined factors. Nature 2011; 475:386-9. [PMID: 21562492 DOI: 10.1038/nature10116] [Citation(s) in RCA: 631] [Impact Index Per Article: 48.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2010] [Accepted: 04/15/2011] [Indexed: 02/07/2023]
Abstract
The generation of functional hepatocytes independent of donor liver organs is of great therapeutic interest with regard to regenerative medicine and possible cures for liver disease. Induced hepatic differentiation has been achieved previously using embryonic stem cells or induced pluripotent stem cells. Particularly, hepatocytes generated from a patient's own induced pluripotent stem cells could theoretically avoid immunological rejection. However, the induction of hepatocytes from induced pluripotent stem cells is a complicated process that would probably be replaced with the arrival of improved technology. Overexpression of lineage-specific transcription factors directly converts terminally differentiated cells into some other lineages, including neurons, cardiomyocytes and blood progenitors; however, it remains unclear whether these lineage-converted cells could repair damaged tissues in vivo. Here we demonstrate the direct induction of functional hepatocyte-like (iHep) cells from mouse tail-tip fibroblasts by transduction of Gata4, Hnf1α and Foxa3, and inactivation of p19(Arf). iHep cells show typical epithelial morphology, express hepatic genes and acquire hepatocyte functions. Notably, transplanted iHep cells repopulate the livers of fumarylacetoacetate-hydrolase-deficient (Fah(-/-)) mice and rescue almost half of recipients from death by restoring liver functions. Our study provides a novel strategy to generate functional hepatocyte-like cells for the purpose of liver engineering and regenerative medicine.
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107
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Li F, Liu P, Liu C, Xiang D, Deng L, Li W, Wangensteen K, Song J, Ma Y, Hui L, Wei L, Li L, Ding X, Hu Y, He Z, Wang X. Hepatoblast-like progenitor cells derived from embryonic stem cells can repopulate livers of mice. Gastroenterology 2010; 139:2158-2169.e8. [PMID: 20801124 DOI: 10.1053/j.gastro.2010.08.042] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Revised: 08/10/2010] [Accepted: 08/19/2010] [Indexed: 12/02/2022]
Abstract
BACKGROUND & AIMS Hepatocyte-like cells can be derived from pluripotent stem cells such as embryonic stem (ES) cells, but ES cell-derived hepatic cells with extensive capacity to repopulate liver have not been identified. We aimed to identify and purify ES cell-derived hepatoblast-like progenitor cells and to explore their capacity for liver repopulation in mice after in vitro expansion. METHODS Unmanipulated mouse ES cells were cultured under defined conditions and allowed to undergo stepwise hepatic differentiation. The derived hepatic cells were examined by morphologic, fluorescence-activated cell sorting, gene expression, and clonal expansion analyses. The capacities of ES cell-derived hepatic progenitor cells to repopulate liver were investigated in mice that were deficient in fumarylacetoacetate hydrolase (Fah) (a model of liver injury). RESULTS Mouse ES cells were induced to differentiate into a population that contained hepatic progenitor cells; this population included cells that expressed epithelial cell adhesion molecule (EpCAM) but did not express c-Kit. Clonal hepatic progenitors that arose from single c-Kit(-)EpCAM(+) cells could undergo long-term expansion and maintain hepatoblast-like characteristics. Enriched c-Kit(-)EpCAM(+) cells and clonally expanded hepatic progenitor cells repopulated the livers of Fah-deficient mice without inducing tumorigenesis. CONCLUSIONS ES cell-derived c-Kit(-)EpCAM(+) cells contain a population of hepatoblast-like progenitor cells that can repopulate livers of mice.
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Abstract
BACKGROUND Research into cell-free fetal (cff) nucleic acids has primarily focused on maternal plasma; however, cff DNA and RNA are also detectable in other body fluids such as amniotic fluid (AF). In AF, cff DNA is present in much greater concentrations than in maternal plasma and represents a pure fetal sample uncontaminated by maternal- and trophoblast-derived nucleic acids. The aim of this review was to summarize the current knowledge on cff nucleic acids in AF and to outline future research directions. METHODS MEDLINE and PREMEDLINE were searched up to August 2010 for original investigations of cell-free RNA or DNA in AF. Sixteen studies were included in the review. RESULTS AF cff DNA represents a physiologically separate pool from cff DNA in maternal plasma. The placenta is not a major source of nucleic acids in AF. It is feasible to isolate cff nucleic acids from small volumes of discarded AF supernatant in sufficient quality and quantity to perform microarray studies and downstream applications such as pathway analysis. This 'discovery-driven approach' has resulted in new information on the pathogenesis of Down syndrome and polyhydramnios. There is otherwise a paucity of information relating to the basic biology and clinical applications of cff nucleic acids in AF. CONCLUSIONS AF supernatant is a valuable and widely available but under-utilized biological resource. Further studies of cff nucleic acids in AF may lead to new insights into human fetal development and ultimately new approaches to antenatal treatment of human disease.
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Xiaoli J, Dongping W, Hui L, Yan X, Hong Z, Xin L. e0666 Vasopressin and epinephrine versus epinephrine alone in management of patients with out of hospital cardiac arrest a metaanalysis. BRITISH HEART JOURNAL 2010. [DOI: 10.1136/hrt.2010.208967.666] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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110
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Hui L, Huanzhen C. e0213 Comparison of olmesartan medoxomil and candesartan cilexetil on anti-inflammatory effect in atherosclerotic rats. BRITISH HEART JOURNAL 2010. [DOI: 10.1136/hrt.2010.208967.213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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111
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Hongmei W, Nanfang L, Junli H, Hui L. e0166 Variation of ADRB2 is associated with common risk factors for cardiovascular. BRITISH HEART JOURNAL 2010. [DOI: 10.1136/hrt.2010.208967.166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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112
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Xiao-Xing L, Ji-Yan L, Hong-Yan W, Hui L, Xin L, Rong L, Chun-Lin H, Guo-Qing H, Gang D. e0004 Hydrogen sulfide inhabits neurons apoptosis in rats after cardiopulmonary resuscitation. BRITISH HEART JOURNAL 2010. [DOI: 10.1136/hrt.2010.208967.4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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113
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Ji-yan L, Xin L, Hui L, Hong-yan W, Rong L, Chun-lin H, Gang D, Xiao-xing L. e0224 Model of cardiac arrest in rats by transcutaneous electrical epicardium stimulation. BRITISH HEART JOURNAL 2010. [DOI: 10.1136/hrt.2010.208967.224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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114
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Ji-Yan L, Xin L, Hui L, Hong-Yan W, Rong L, Chun-Lin H, Gang D, Xiao-Xing L. e0005 Model of cardiac arrest in rats by transcutaneous electrical epicardium stimulation. BRITISH HEART JOURNAL 2010. [DOI: 10.1136/hrt.2010.208967.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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115
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He Z, Zhang H, Zhang X, Xie D, Chen Y, Wangensteen KJ, Ekker SC, Firpo M, Liu C, Xiang D, Zi X, Hui L, Yang G, Ding X, Hu Y, Wang X. Liver xeno-repopulation with human hepatocytes in Fah-/-Rag2-/- mice after pharmacological immunosuppression. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:1311-9. [PMID: 20651238 DOI: 10.2353/ajpath.2010.091154] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Functional human hepatocytes xeno-engrafted in mouse liver can be used as a model system to study hepatitis virus infection and vaccine efficacy. Significant liver xeno-repopulation has been reported in two kinds of genetically modified mice that have both immune deficiency and liver injury-induced donor hepatocyte selection: the uPA/SCID mice and Fah(-/-) Rag2(-/-)Il2rg(-/-) mice. The lack of hardy breeding and the overly elaborated technique in these two models may hinder the potential future application of these models to hepatitis virus infection and vaccination studies. Improving the transplantation protocol for liver xeno-repopulation from human hepatocytes will increase the model efficiency and application. In this study, we successfully apply immunosuppressive drug treatments of anti-asialo GM1 and FK506 in Fah(-/-)Rag2(-/-) mice, resulting in significant liver xeno-repopulation from human hepatocytes and human fetal liver cells. This methodology decreases the risk of animal mortality during breeding and surgery. When infected with hepatitis B virus (HBV) sera, Fah(-/-)Rag2(-/-) mice with liver xeno-repopulation from human hepatocytes accumulate significant levels of HBV DNA and HBV proteins. Our new protocol for humanized liver could be applied in the study of human hepatitis virus infection in vivo, as well as the pharmacokinetics and efficacy of potential vaccines.
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116
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Huang P, Han J, Hui L. MAPK signaling in inflammation-associated cancer development. Protein Cell 2010; 1:218-26. [PMID: 21203968 DOI: 10.1007/s13238-010-0019-9] [Citation(s) in RCA: 174] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Accepted: 12/09/2009] [Indexed: 12/19/2022] Open
Abstract
Mitogen-activated protein (MAP) kinases comprise a family of protein-serine/threonine kinases, which are highly conserved in protein structures from unicellular eukaryotic organisms to multicellular organisms, including mammals. These kinases, including ERKs, JNKs and p38s, are regulated by a phosphorelay cascade, with a prototype of three protein kinases that sequentially phosphorylate one another. MAPKs transduce extracellular signals into a variety of cellular processes, such as cell proliferation, survival, death, and differentiation. Consistent with their essential cellular functions, MAPKs have been shown to play critical roles in embryonic development, adult tissue homeostasis and various pathologies. In this review, we discuss recent findings that reveal the profound impact of these pathways on chronic inflammation and, particularly, inflammation-associated cancer development.
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117
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Tu X, Wen D, Yun Z, Wei W, Liang Z, Hui L, You Z. UP-3.056: Lithotripsy by Outer Sheath of Resectoscope Combined with TURP in the Treatment of Benign Prostatic Hyperplasia Complicated with Bladder Stones. Urology 2009. [DOI: 10.1016/j.urology.2009.07.059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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118
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Hui L, Zatloukal K, Scheuch H, Stepniak E, Wagner EF. Proliferation of human HCC cells and chemically induced mouse liver cancers requires JNK1-dependent p21 downregulation. J Clin Invest 2008; 118:3943-53. [PMID: 19033664 PMCID: PMC2579707 DOI: 10.1172/jci37156] [Citation(s) in RCA: 254] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Accepted: 10/01/2008] [Indexed: 12/11/2022] Open
Abstract
JNK proteins have been shown to be involved in liver carcinogenesis in mice, but the extent of their involvement in the development of human liver cancers is unknown. Here, we show that activation of JNK1 but not JNK2 was increased in human primary hepatocellular carcinomas (HCCs). Further, JNK1 was required for human HCC cell proliferation in vitro and tumorigenesis after xenotransplantation. Importantly, mice lacking JNK1 displayed decreased tumor cell proliferation in a mouse model of liver carcinogenesis and decreased hepatocyte proliferation in a mouse model of liver regeneration. In both cases, impaired proliferation was caused by increased expression of p21, a cell-cycle inhibitor, and reduced expression of c-Myc, a negative regulator of p21. Genetic inactivation of p21 in JNK1-/- mice restored hepatocyte proliferation in models of both liver carcinogenesis and liver regeneration, and overexpression of c-Myc increased proliferation of JNK1-/- liver cells. Similarly, JNK1 was found to control the proliferation of human HCC cells by affecting p21 and c-Myc expression. Pharmacologic inhibition of JNK reduced the growth of both xenografted human HCC cells and chemically induced mouse liver cancers. These findings provide a mechanistic link between JNK activity and liver cell proliferation via p21 and c-Myc and suggest JNK targeting can be considered as a new therapeutic approach for HCC treatment.
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MESH Headings
- Animals
- Carcinoma, Hepatocellular/chemically induced
- Carcinoma, Hepatocellular/genetics
- Carcinoma, Hepatocellular/metabolism
- Carcinoma, Hepatocellular/therapy
- Cell Line, Tumor
- Cell Proliferation
- Cyclin-Dependent Kinase Inhibitor p21/genetics
- Cyclin-Dependent Kinase Inhibitor p21/metabolism
- Female
- Hepatocytes/metabolism
- Humans
- Liver Neoplasms/chemically induced
- Liver Neoplasms/genetics
- Liver Neoplasms/metabolism
- Liver Neoplasms/therapy
- Liver Regeneration/drug effects
- Liver Regeneration/genetics
- Male
- Mice
- Mice, Knockout
- Mice, Nude
- Mitogen-Activated Protein Kinase 8/genetics
- Mitogen-Activated Protein Kinase 8/metabolism
- Neoplasms, Experimental/chemically induced
- Neoplasms, Experimental/genetics
- Neoplasms, Experimental/metabolism
- Neoplasms, Experimental/therapy
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119
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Hu K, Hui F, Hui L. PP-011 An undamaged bulge of ɛ is essential for initiating priming of DHBV reverse transcriptase. Int J Infect Dis 2008. [DOI: 10.1016/s1201-9712(09)60162-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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120
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Pemberton J, Jerosch-Herold M, Li X, Hui L, Silberbach M, Woodward W, Thiele K, Kenny A, Sahn DJ. Accuracy of real-time, three-dimensional Doppler echocardiography for stroke volume estimation compared with phase-encoded MRI: an in vivo study. Heart 2008; 94:1212-3. [DOI: 10.1136/hrt.2008.147751] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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121
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Hui L, Vaughan JI, Nelson M. Effect of labor on postpartum clearance of cell-free fetal DNA from the maternal circulation. Prenat Diagn 2008; 28:304-8. [PMID: 18324618 DOI: 10.1002/pd.1975] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE The aim of this study was to compare the effect of mode of delivery on the postpartum clearance of cell-free fetal (cff) DNA. METHODS Women who gave birth to a single-term male infant by any mode of delivery had blood collected on three occasions: within 3 h of birth, on day 1-2 postpartum and at 2 weeks postpartum. The SRY sequence was used as a marker of cff DNA, and was detected using conventional PCR. RESULTS Eighty-seven women were included in the study. There were 28 women in the elective caesarean section group and 59 in the labor group. Cell-free fetal DNA was detected in 38/87 (44%) of women within 3 h of birth. There was a significant difference between the group that labored and the group that did not (54 vs 21%, p = 0.003). Twelve percent of women who labored had persistent cff DNA on day 1-2 postpartum, compared with none of the women who delivered without labor. No woman had DNA that persisted up to 2 weeks postpartum. CONCLUSION The presence of labor increases the rate of detectable DNA in women within 3 h of birth and on day 1-2 postpartum. Postpartum clearance was completed by 2 weeks in all women tested regardless of mode of delivery.
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122
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Hui L, Bakiri L, Stepniak E, Wagner EF. p38alpha: a suppressor of cell proliferation and tumorigenesis. Cell Cycle 2007; 6:2429-33. [PMID: 17957136 DOI: 10.4161/cc.6.20.4774] [Citation(s) in RCA: 149] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The mitogen-activated protein kinase (MAPK) p38alpha is involved in numerous biological processes and is a drug target for inflammation-associated diseases. Genetic analysis in mice demonstrated that fetuses lacking p38alpha are embryonic lethal owing to impaired placental development. The function of p38alpha in mice after birth remained unclear until conditional alleles of p38alpha were used. It was found that p38alpha is essential for lung function in both neonatal and adult mice. Increased proliferation and impaired differentiation are the hallmarks of p38alpha-deficient cells. Moreover, mice deficient in p38alpha are prone to cancer development using carcinogen or oncogene-induced cancer models. p38alpha can suppress cell proliferation by antagonizing the JNK/c-Jun pathway, which is an important regulator of proliferation and apoptosis. These findings suggest that therapeutic inhibition of p38 might lead to unwanted proliferation. Therefore, a combined inhibition of p38 and other pathways, such as the JNK pathway, should be considered for targeting cancer inflammation.
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123
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Wada T, Stepniak E, Hui L, Leibbrandt A, Katada T, Nishina H, Wagner EF, Penninger JM. Antagonistic control of cell fates by JNK and p38-MAPK signaling. Cell Death Differ 2007; 15:89-93. [PMID: 17762881 DOI: 10.1038/sj.cdd.4402222] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
During the development and organogenesis of all multicellular organisms, cell fate decisions determine whether cells undergo proliferation, differentiation, or aging. Two independent stress kinase signaling pathways, p38-MAPK, and JNKs, have evolved that relay developmental and environmental cues to determine cell responses. Although multiple stimuli can activate these two stress kinase pathways, the functional interactions and molecular cross-talks between these common second signaling cascades are poorly elucidated. Here we report that JNK and p38-MAPK pathways antagonistically control cellular senescence, oncogenic transformation, and proliferation in primary mouse embryonic fibroblasts (MEFs). Similarly, genetic inactivation of the JNK pathway results in impaired proliferation of fetal hepatoblasts in vitro and defective adult liver regeneration in vivo, which is rescued by inhibition of the p38-MAPK pathway. Thus, the balance between the two stress-signaling pathways, MKK7-JNK and MKK3/6-p38-MAPK, determines cell fate and links environmental and developmental stress to cell cycle arrest, senescence, oncogenic transformation, and adult tissue regeneration.
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124
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Hui L, Bakiri L, Mairhorfer A, Schweifer N, Haslinger C, Kenner L, Komnenovic V, Scheuch H, Beug H, Wagner EF. p38alpha suppresses normal and cancer cell proliferation by antagonizing the JNK-c-Jun pathway. Nat Genet 2007; 39:741-9. [PMID: 17468757 DOI: 10.1038/ng2033] [Citation(s) in RCA: 296] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Accepted: 03/26/2007] [Indexed: 02/07/2023]
Abstract
The mitogen-activated protein kinase (MAPK) p38alpha controls inflammatory responses and cell proliferation. Using mice carrying conditional Mapk14 (also known as p38alpha) alleles, we investigated its function in postnatal development and tumorigenesis. When we specifically deleted Mapk14 in the mouse embryo, fetuses developed to term but died shortly after birth, probably owing to lung dysfunction. Fetal hematopoietic cells and embryonic fibroblasts deficient in p38alpha showed increased proliferation resulting from sustained activation of the c-Jun N-terminal kinase (JNK)-c-Jun pathway. Notably, in chemical-induced liver cancer development, mice with liver-specific deletion of Mapk14 showed enhanced hepatocyte proliferation and tumor development that correlated with upregulation of the JNK-c-Jun pathway. Furthermore, inactivation of JNK or c-Jun suppressed the increased proliferation of Mapk14-deficient hepatocytes and tumor cells. These results demonstrate a new mechanism whereby p38alpha negatively regulates cell proliferation by antagonizing the JNK-c-Jun pathway in multiple cell types and in liver cancer development.
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125
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Perdiguero E, Ruiz-Bonilla V, Gresh L, Hui L, Ballestar E, Sousa-Victor P, Baeza-Raja B, Jardí M, Bosch-Comas A, Esteller M, Caelles C, Serrano AL, Wagner EF, Muñoz-Cánoves P. Genetic analysis of p38 MAP kinases in myogenesis: fundamental role of p38alpha in abrogating myoblast proliferation. EMBO J 2007; 26:1245-56. [PMID: 17304211 PMCID: PMC1817635 DOI: 10.1038/sj.emboj.7601587] [Citation(s) in RCA: 193] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2006] [Accepted: 01/10/2007] [Indexed: 02/06/2023] Open
Abstract
The p38 mitogen-activated protein kinase (MAPK) pathway plays a critical role in skeletal muscle differentiation. However, the relative contribution of the four p38 MAPKs (p38alpha, p38beta, p38gamma and p38delta) to this process is unknown. Here we show that myoblasts lacking p38alpha, but not those lacking p38beta or p38delta, are unable to differentiate and form multinucleated myotubes, whereas p38gamma-deficient myoblasts exhibit an attenuated fusion capacity. The defective myogenesis in the absence of p38alpha is caused by delayed cell-cycle exit and continuous proliferation in differentiation-promoting conditions. Indeed, activation of JNK/cJun was enhanced in p38alpha-deficient myoblasts leading to increased cyclin D1 transcription, whereas inhibition of JNK activity rescued the proliferation phenotype. Thus, p38alpha controls myogenesis by antagonizing the activation of the JNK proliferation-promoting pathway, before its direct effect on muscle differentiation-specific gene transcription. More importantly, in agreement with the defective myogenesis of cultured p38alpha(Delta/Delta) myoblasts, neonatal muscle deficient in p38alpha shows cellular hyperproliferation and delayed maturation. This study provides novel evidence of a fundamental role of p38alpha in muscle formation in vitro and in vivo.
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