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2508 citation(s) found for "Xu, Yang".

Elevated Serum IL-12 Levels Attenuate Tumor Immunity Via the TIM-3/Gal-9 Axis and Worsen Patient Prognosis in Follicular B-Cell Non-Hodgkin Lymphoma (NHL).
Ziesmer, Steven C., Novak, Anne J. , Niki, Toshiro , Hirashima, Mitsuomi , Ansell, Stephen M. , Yang, Zhi-Zhang , Witzig, Thomas E.

Blood | October 9, 2019 | Volume: 114 | Issue: 22 | Pages: 2668-2668

10.1182/blood.v114.22.2668.2668 Get It

Abstract Abstract 2668 Poster Board II-644 Interleukin-12 (IL-12) has been demonstrated to induce IFN-g production by T and NK cells and thereby contribute to anti-tumor immunity. However, the administration of IL-12 to boost anti-tumor immunity in B-cell lymphoma has shown no clinical benefit. In fact, clinical trials of IL-12 in combination with rituximab in follicular B-cell lymphoma (FL) showed a lower response rate in patients treated with the combination than in patients treated with rituximab alone (Clin Cancer Res. 2006 15; 12:6056-63). The goal of this study was therefore to determine the role of IL-12 in the antitumor response in B-cell NHL. First, we measured serum levels of IL-12 in patients with untreated FL before treatment with rituximab and normal healthy controls. We found that serum IL-12 levels were elevated in FL patients compared to healthy individuals (median: 0.50 ng/ml, n=30 vs 0.32 ng/ml, n=22; p= 0.03) and that elevated serum IL-12 levels were associated with a poor outcome in these patients when treated with rituximab alone as initial therapy. Using 0.56 ng/ml as a cutoff, patients with serum IL-12 levels of greater than 0.56 ng/ml had a significantly shorter time to progression than patients with IL-12 levels less than 0.56 ng/ml (12 months versus 40 months; p=0.001). To determine the mechanism by which IL-12 may contribute to a poor prognosis, we investigated the role of IL-12 on induction of immune tolerance. First, we found that TIM-3, a member of the T cell immunoglobulin and mucin domain-containing protein (TIM) family that functions to terminate TH1-mediated immunity and promote tolerance, was constitutively expressed on a subset of intratumoral T cells accounting for approximately 15% and 25% of the intratumoral CD4+ and CD8+ T cells, respectively. In contrast, less than 2% of T cells from peripheral blood of normal individuals expressed TIM-3. TIM-3-expressing T cells were distinct from regulatory T cells since CD25+ and Foxp3+ T cells lacked TIM-3 expression. Secondly, we found that TIM-3-expressing CD4+ cells were unable to produce cytokines such as IL-2, IFN-g or IL-17 and that TIM-3-expressing CD8+ T cells failed to produce Granzyme B, IFN-g or IL-2. We also observed that TIM-3-expressing T cells lost the capacity to proliferate in response to TCR activation. These results suggest that TIM-3 expressing CD4+ and CD8+ T cells are functionally exhausted. Thirdly, we observed that TIM-3 expression on T cells could be induced by activation and that IL-12 was the strongest stimulus to induce TIM-3 expression on CD4+ and CD8+ T cells. Finally, we found by immunohistochemistry (IHC) that Galectin-9 (Gal-9), a ligand for TIM-3, was abundantly expressed on lymphoma B cells. In vitro incubation with a stable form of Gal-9 induced apoptosis of CD4+ and CD8+ T cells in a dose dependent fashion. Gal-9-mediated apoptosis of T cells was attenuated by a TIM-3 Fc protein and isolated TIM-3+ T cells exhibited a significantly higher apoptosis rate than TIM-3− T cells in response to Gal-9. These results indicate that, in contrast to the observations in vitro or in vivo in mice, IL-12 actually plays a detrimental role in lymphoma patients. Given the findings that IL-12 strongly induces TIM-3 expression on effector T cells and that the TIM-3/Gal-9 pathway impairs the immune response, we conclude that increased serum levels of IL-12 suppress anti-tumor immunity in follicular lymphoma patients and is associated with a poor prognosis. Disclosures: Witzig: Novartis: Research Funding.
A Novel IL-12-TIM-3 Pathway Induces T Cell Exhaustion and Predicts Reduced Survival In Patients with Follicular B-Cell Non-Hodgkin Lymphoma
Grote, Deanna M., Ziesmer, Steven C., Niki, Toshiro , Hirashima, Mitsuomi , Novak, Anne J. , Ansell, Stephen M. , Yang, Zhi-Zhang , Witzig, Thomas E.

Blood | October 9, 2019 | Volume: 116 | Issue: 21 | Pages: 143-143

10.1182/blood.v116.21.143.143 Get It

Abstract Abstract 143 IL-12 induces IFN-g production and contributes to anti-tumor immunity. However, administration of IL-12 in cancer patients has resulted in a limited clinical benefit. In follicular B-cell lymphoma (FL), a clinical trial of IL-12 in combination with rituximab showed a lower response rate in patients treated with the combination than in patients treated with rituximab alone (Clin Cancer Res 2006), suggesting that, in contrast to the observations in vitro or in vivo in mice, IL-12 actually plays a detrimental role in FL patients. Recently, a type of immune response, termed “ T cell exhaustion” describing a condition in which T cells exhibit reduced differentiation, proliferation, and effector function, has been shown to impair anti-tumor immunity and result in disease progression. TIM-3, a family member of T-cell immunoglobulin and mucin domian-containing proteins, inhibits TH1-mediated immune response and promotes immunological tolerance. A recent study has suggested that TIM-3 may play an important role in mediating T cell exhaustion. However, the biological and clinical relevance of TIM-3 in cancers remains completely unknown. In this study, we determined whether T cell exhaustion exists in the tumor microenvironment, whether IL-12 contributes to T cell exhaustion, and whether TIM-3-mediated T cell exhaustion impacts patient outcome in FL. We found that serum IL-12 levels were elevated in FL patients compared to healthy individuals (median: 0.50 ng/ml, n=30 vs 0.32 ng/ml, n=22; p= 0.03) and that elevated serum IL-12 levels were associated with a poor outcome in these patients when treated with rituximab alone as initial therapy. Using 0.56 ng/ml as a cutoff, patients with serum IL-12 levels of greater than 0.56 ng/ml had a significantly shorter time to progression than patients with IL-12 levels less than 0.56 ng/ml (12 months versus 40 months; p=0.001). Both lymphoma B cells and monocytes were able to produce IL-12 and contributed to elevated serum levels of IL-12 in FL. Importantly, we found that IL-12 strongly induced TIM-3 expression in a dose-dependent manner. Endogenous production of IL-12 by lymphoma B cells and monocytes was capable of regulating TIM-3 expression on T cells from FL. As a consequence, TIM-3 was highly expressed on a subset of T cells from PBMCs or lymph nodes from FL patients while its expression was negligible or moderate on T cells from normal PBMCs or benign lymph nodes, respectively. The number of TIM-3-expressing T cells accounted for approximately 32% and 39% of CD4+ or CD8+ T cells in biopsy specimens and 6.2% and 6.7% in peripheral blood of FL patients. TIM-3+ T cells, co-expressed with PD-1, exhibited a reduced ability to proliferate and decreased cytokine production compared to TIM-3- T cells. Similarly, IL-12-induced TIM-3+ T cells gradually lost the capacity to produce cytokines over a period of time. These results suggest that TIM-3-expressing T cells are functionally exhausted. In addition, TIM-3+ T cells were prone to apoptotic induction by its ligand galectin (Gal) -9. The phosphorylation of p38 was higher in TIM-3+ T cells compared to TIM-3- T cells when exposed to Gal-9, suggesting MAPK pathway was involved in Gal-9-mediated apoptosis of TIM-3+ T cells. Finally, increased numbers of intratumoral TIM-3-expressing cells were associated with a higher histological grade, higher LDH levels and a poor survival in FL patients. Taken together, these results indicate that IL-12, in contrast to its role in augmenting immune response through IFN-g, induces T cell exhaustion by upregulating TIM-3 expression. We further demonstrated that lymphoma B cells produce IL-12 thereby contributing to T cell exhaustion by promoting TIM-3 expression on intratumoral T cells. Impairment of anti-tumor immunity due to T cell exhaustion induced by the IL-12-TIM-3 pathway may account for the observation that high levels of serum IL-12 and increased number of TIM-3+CD4+ T cells correlate with a worse outcome in FL patients. These findings not only reveal a novel IL-12-TIM-3 pathway that plays an important role in impairing tumor immunity and detrimentally affecting prognosis in FL patients, but may have therapeutic potential for cancer patients. Disclosures: No relevant conflicts of interest to declare.
The duration of acupuncture effects and its associated factors in chronic severe functional constipation: secondary analysis of a randomized controlled trial
Wang, Yang , Zhou, Kehua , Bauer, Brent A. , Su, Tongsheng, Mo, Qian , Liu, Yan , Liu, Baoyan , Liu, Zhishun

Therapeutic Advances in Gastroenterology | October 9, 2019 | Volume: 12 | Issue: No issue available | Pages: No page available

10.1177/1756284819881859 | PMID 31636713 Get It

Background: Electroacupuncture (EA) has been shown to improve complete spontaneous bowel movements (CSBMs), but the duration of its effects remains unknown. The objective of this study was to explore the duration of acupuncture effects after treatment and its associated factors for chronic severe functional constipation (CSFC). Methods: This was a secondary analysis of a multicenter, randomized, sham-acupuncture (SA) controlled trial that included 1075 participants with CSFC. The primary outcome, the duration of acupuncture effects after treatment, was the number of weeks during the 12-week follow-up period that participants were to meet the weekly CSBM responder criteria. A weekly CSBM responder was defined as a participant who had at least three CSBMs for a given week and an increase from baseline of at least one CSBM for that same week. We performed a retrospective multivariate analysis to explore potential factors associated with sustained acupuncture effects. Results: The duration of acupuncture effects in the EA group (5.5 weeks) was significantly higher than the duration of SA effects in the SA group (2.2 weeks) with a between-group difference of 3.2 weeks (95% CI, 2.77–3.78; p < 0.001). A younger age and higher baseline CSBMs per week [regression coefficient (RC) –0.06, 95% confidence interval (CI) (−0.06 to −0.04); RC 2.43, 95% CI 1.78–3.60; respectively] were associated with longer durations of acupuncture effects. Conclusions: EA had sustained post-treatment effects for CFSC. A significant association among a younger age, higher baseline CSBMs and sustained acupuncture effects was observed. Further research is needed to confirm the association. Trial registration: ClinicalTrials.gov (NCT01726504). Registered on 26 August 2012.
Deep-learning approach to identifying cancer subtypes using high-dimensional genomic data
Chen, Runpu , Goodison, Steve , Yang, Le , Sun, Yijun

Bioinformatics | October 8, 2019 | Volume: 36 | Issue: 5 | Pages: 1476-1483

10.1093/bioinformatics/btz769 | PMID 31603461 Get It

Abstract Motivation Cancer subtype classification has the potential to significantly improve disease prognosis and develop individualized patient management. Existing methods are limited by their ability to handle extremely high-dimensional data and by the influence of misleading, irrelevant factors, resulting in ambiguous and overlapping subtypes. Results To address the above issues, we proposed a novel approach to disentangling and eliminating irrelevant factors by leveraging the power of deep learning. Specifically, we designed a deep-learning framework, referred to as DeepType, that performs joint supervised classification, unsupervised clustering and dimensionality reduction to learn cancer-relevant data representation with cluster structure. We applied DeepType to the METABRIC breast cancer dataset and compared its performance to state-of-the-art methods. DeepType significantly outperformed the existing methods, identifying more robust subtypes while using fewer genes. The new approach provides a framework for the derivation of more accurate and robust molecular cancer subtypes by using increasingly complex, multi-source data. Availability and implementation An open-source software package for the proposed method is freely available at http://www.acsu.buffalo.edu/~yijunsun/lab/DeepType.html. Supplementary information Supplementary data are available at Bioinformatics online.
991 BALAD and BALAD-2 Predict Survival of Hepatocellular Carcinoma Patients: A North American Cohort Study
Negron, Gabriela, Ahn, Keun Soo , Yang, Ju Dong , Giama, Nasra H., Harmsen, William S. , Therneau, Terry M. , Wongjarupong, Nicha , Yang, Ju Dong , Mara, Kristin C. , Roberts, Lewis R.

American Journal of Gastroenterology | October 8, 2019 | Volume: 114 | Issue: 1 | Pages: S576-S576

10.14309/01.ajg.0000593500.58446.21 Get It

INTRODUCTION: The discontinuous BALAD and continuous BALAD-2 scores derived from bilirubin, albumin, alpha-fetoprotein (AFP), Lens culinaris agglutinin-reactive AFP (AFP-L3), and des-gamma-carboxyprothrombin (DCP) are effective in predicting HCC patient mortality, but have not been validated in North America. We validated the BALAD and BALAD-2 scores in North America. METHODS: Data from 148 HCC patients seen from 2000–2015 with results for all five biomarkers at diagnosis were abstracted. Hazard ratios (HR) and C-statistics were calculated. RESULTS: 75 of the 148 patients died during a median follow-up of 33 months (0.3-145 months),. The 1-year and 3-year survival rates were 70.8% and 47.6%, respectively. 114 (77%) patients had cirrhosis with a median MELD of 9.5 (range 6.4-29.5). HCC etiologies were HCV (34%), NASH (34%), alcohol (14%), and HBV (10%). Primary treatments were liver transplant, 21 (14%), surgical resection, 32 (22%), local ablation, 10 (7%), transarterial chemoembolization or radioembolization, 47 (32%), chemotherapy, 11 (7%), best supportive care, 9 (6%), and unknown treatment, 18 (12%). MELD, tumor size (cm), ≥2 tumors, tumor number, and neutrophil-lymphocyte ratio >4 significantly increased mortality with HR (95%CI) of 1.12 (1.06–1.18) per unit increase in MELD, 1.06 (1.0004–1.12) per cm increase in size, 1.21 (1.03–1.43) per number of tumor, and 1.93 (1.16–3.24). For the BALAD score analysis, 12, 49, 40, 31, 16 and 0 patients had BALAD scores of 0–5 respectively. The HR (95%CI) for death were 1.24 (0.42–3.67), 1.79 (0.61–5.26), 2.83 (0.95–8.38), and 7.19 (2.26–22.91) for BALAD scores 1, 2, 3, and 4 vs. BALAD 0. For the BALAD-2 analysis, 58, 35, 33, and 22 patients were BALAD-2 classes 1, 2, 3, and 4. The HR (95%CI) for death were 1.25 (0.65–2.40), 1.75 (0.94–3.23), and 6.20 (3.29–11.68) for BALAD-2 classes 2, 3, and 4 vs. BALAD-2 class 1. A multivariate model incorporating maximal tumor diameter, tumor number, neutrophil-lymphocyte ratio and BALAD had HR of 1.43 (1.14–1.81) per increase of 1 BALAD score. A similar multivariate model with BALAD-2 had HR of 1.50 (1.18–1.90) per increase of 1 BALAD-2 class. BALAD, BALAD-2 and BCLC had similar C-statistics of 0.69, 0.68, and 0.67. CONCLUSION: The BALAD score and BALAD-2 class at HCC diagnosis can predict survival of HCC patients in North America. AFP, AFP-L3, and DCP in the BALAD models incorporate HCC tumor biology and make the BALAD model distinguish from other previous predictive models.
Tai Chi for patients with mild cognitive impairment
Yang, Juan , Chon, Tony Y. , Li, Guangxi , Mallory, Molly J., Bublitz, Sara E. , Do, Alexander , Xiao, Lizu, Xiong, Donglin, Bauer, Brent A. , Li, Guangxi

Medicine | October 2, 2019 | Volume: 98 | Issue: 40 | Pages: e17118

10.1097/md.0000000000017118 | PMID 31577701 Get It

Abstract Background: Mild cognitive impairment (MCI) is an intermediate stage between the cognitive changes of normal aging and early dementia. Tai Chi (TC) may be particularly beneficial to patients with MCI due to its whole-body coordination characteristics. This systematic review protocol aims to outline the methods that will be used to assess the comparative effectiveness and safety of TC for MCI through a systematic review and meta-analysis. Methods: A systematic review will identify and evaluate randomized controlled trials (RCTs) that examined the effects and safety of TC compared to a placebo, conventional treatment, and no treatment on cognitive function in individuals with MCI. Studies from databases of MEDLINE, PubMed, Embase, Global Health, Cochrane Library, and Scopus from January 1990 to March 2019 reported in English will be searched. Two independent reviewers will screen the studies for inclusion with the eligibility criteria and extract data. Risk of bias of individual studies will be assessed in line with Cochrane risk of bias tool. The overall quality of cumulative evidence will be assessed using selected Grading of Recommendations, Assessment, Development, and Evaluations criteria. Statistics will be used for heterogeneity assessment, sensitivity analysis, data synthesis, generating funnel plots, and subgroup analysis. Meta-analysis will be performed, if sufficiently homogeneous studies are found. A narrative synthesis will be conducted, grouping studies by exposure and outcome definitions, and describing any differences by subgroups. Results: This study will provide practical and targeted evidence in investigating the impact of TC exercise for individuals with MCI. Conclusion: The findings of our study will provide updated evidence to determine whether TC is an effective intervention to patients with MCI. Trial registration number: International Prospective Register for Systematic Reviews (PROSPERO) number CRD42019125104.
A Transcriptionally Definable Subgroup of Triple-Negative Breast and Ovarian Cancer Samples Shows Sensitivity to HSP90 Inhibition
Shee, Kevin , Wells, Jason D. , Ung, Matthew , Hampsch, Riley A. , Traphagen, Nicole A. , Liu, Stephanie C., Zeldenrust, Megan A., Wang, Liewei , Yu, Jia , Demidenko, Eugene , Kettenbach, Arminja N. , Miller, Todd W. , Cheng, Chao , Yang, Wei , Kalari, Krishna R. , Boughey, Judy C. , Cheng, Chao , Goetz, Matthew P.

Clinical Cancer Research | September 26, 2019 | Volume: 26 | Issue: 1 | Pages: 159-170

10.1158/1078-0432.ccr-18-2213 | PMID 31558472 Get It

Abstract Purpose: We hypothesized that integrated analysis of cancer types from different lineages would reveal novel molecularly defined subgroups with unique therapeutic vulnerabilities. On the basis of the molecular similarities between subgroups of breast and ovarian cancers, we analyzed these cancers as a single cohort to test our hypothesis. Experimental Design: Identification of transcriptional subgroups of cancers and drug sensitivity analyses were performed using mined data. Cell line sensitivity to Hsp90 inhibitors (Hsp90i) was tested in vitro. The ability of a transcriptional signature to predict Hsp90i sensitivity was validated using cell lines, and cell line- and patient-derived xenograft (PDX) models. Mechanisms of Hsp90i sensitivity were uncovered using immunoblot and RNAi. Results: Transcriptomic analyses of breast and ovarian cancer cell lines uncovered two mixed subgroups comprised primarily of triple-negative breast and multiple ovarian cancer subtypes. Drug sensitivity analyses revealed that cells of one mixed subgroup are significantly more sensitive to Hsp90i compared with cells from all other cancer lineages evaluated. A gene expression classifier was generated that predicted Hsp90i sensitivity in vitro, and in cell line- and PDXs. Cells from the Hsp90i-sensitive subgroup underwent apoptosis mediated by Hsp90i-induced upregulation of the proapoptotic proteins Bim and PUMA. Conclusions: Our findings identify Hsp90i as a potential therapeutic strategy for a transcriptionally defined subgroup of ovarian and breast cancers. This study demonstrates that gene expression profiles may be useful to identify therapeutic vulnerabilities in tumor types with limited targetable genetic alterations, and to identify molecularly definable cancer subgroups that transcend lineage.
The Miami International Evidence-based Guidelines on Minimally Invasive Pancreas Resection
Asbun, Horacio J. , Moekotte, Alma , Vissers, Frederique L., Kunzler, F. , Cipriani, Federica , D’Angelica, Michael I. , Balduzzi, Alberto , Bassi, Claudio , Björnsson, Bergþór , Boggi, Ugo , Callery, Mark P., Chiaro, Marco Del , Coimbra, Felipe José Fernández , Conrad, Claudius , Cook, Andrew , Coppola, Alessandro , Dervenis, Christos, Dokmak, Safi , Edil, Barish H. , Giulianotti, Pier Cristoforo , Hansen, Paul D., Heijde, Nicky van der , Hilst, Jony van , Hester, Caitlin A. , Hogg, Melissa E. , Jarufe, Nicolás , Jeyarajah, D. Rohan, Kim, Song Cheol, Khatkov, Igor , Kokudo, Norihiro , Kooby, David A. , Korrel, Maarten , Leon, Francisco J. de, Lluís, Núria , Lof, Sanne , Demartines, Nicolas , Merchant, Nipun B. , Molenaar, I. Quintus, Moravek, Cassadie, Mou, Yiping , Nealon, William H. , Palanivelu, Chinnusamy, Pessaux, Patrick , Pitt, Henry A. , Primrose, John N., Rawashdeh, Arab , Sanford, Dominic E. , Senthilnathan, Palanisamy, Shrikhande, Shailesh V. , Stauffer, John , Takaori, Kyoichi , Tang, Chung Ngai, Vollmer, Charles M., Wakabayashi, Go , Walsh, R. Matthew , Wang, Shin-E, Zinner, Michael J. , Wolfgang, Christopher L. , Zureikat, Amer H. , Zwart, M. , Conlon, Kevin C. , Kendrick, Michael L., Zeh, Herbert J. , Hilal, Mohammad Abu, Besselink, Marc G. , Primrose, John , Hilal, Mohammad Abu , Demartines, N , A Stauffer, John , Alseidi, Adnan A. , Edwin, Bjørn , Han, Ho-Seong , Jeyarajah, D. Rohan , Keck, Tobias , Machado, Marcel Autran C. , Martinie, John B. , Moravek, Cassadie, Nakamura, Masafumi , Palanivelu, Chinnusamy , Polanco, Patricio Marcelo , Talamonti, Marina , Wang, Shin‐E , Kendrick, Michael L. , Besselink, Marc G , Cipriani, Federica

Annals of Surgery | September 22, 2019 | Volume: 271 | Issue: 1 | Pages: 1-14

10.1097/sla.0000000000003590 | PMID 31567509 Get It

Objective: The aim of this study was to develop and externally validate the first evidence-based guidelines on minimally invasive pancreas resection (MIPR) before and during the International Evidence-based Guidelines on Minimally Invasive Pancreas Resection (IG-MIPR) meeting in Miami (March 2019). Summary Background Data: MIPR has seen rapid development in the past decade. Promising outcomes have been reported by early adopters from high-volume centers. Subsequently, multicenter series as well as randomized controlled trials were reported; however, guidelines for clinical practice were lacking. Methods: The Scottisch Intercollegiate Guidelines Network (SIGN) methodology was used, incorporating these 4 items: systematic reviews using PubMed, Embase, and Cochrane databases to answer clinical questions, whenever possible in PICO style, the GRADE approach for assessment of the quality of evidence, the Delphi method for establishing consensus on the developed recommendations, and the AGREE-II instrument for the assessment of guideline quality and external validation. The current guidelines are cosponsored by the International Hepato-Pancreato-Biliary Association, the Americas Hepato-Pancreato-Biliary Association, the Asian-Pacific Hepato-Pancreato-Biliary Association, the European-African Hepato-Pancreato-Biliary Association, the European Association for Endoscopic Surgery, Pancreas Club, the Society of American Gastrointestinal and Endoscopic Surgery, the Society for Surgery of the Alimentary Tract, and the Society of Surgical Oncology. Results: After screening 16,069 titles, 694 studies were reviewed, and 291 were included. The final 28 recommendations covered 6 topics; laparoscopic and robotic distal pancreatectomy, central pancreatectomy, pancreatoduodenectomy, as well as patient selection, training, learning curve, and minimal annual center volume required to obtain optimal outcomes and patient safety. Conclusion: The IG-MIPR using SIGN methodology give guidance to surgeons, hospital administrators, patients, and medical societies on the use and outcome of MIPR as well as the approach to be taken regarding this challenging type of surgery.
Immune Thrombocytopenia—A Neglected Adverse Event of PD-1 and PD-L1 Inhibitors in Clinical Trials—In Reply
Yang, Fang , Wang, Michael , Wang, Yucai

JAMA Oncology | September 19, 2019 | Volume: 5 | Issue: 11 | Pages: 1641

10.1001/jamaoncol.2019.3608 | PMID 31536125 Get It

Disruption of Robo2-Baiap2 integrated signaling drives cystic disease
Li, Qinggang, Cui, Shaoyuan , Ma, Qian , Liu, Ying , Geng, Guangrui , Agborbesong, Ewud , Ren, Chongyu, Wei, Kai , Yang, Jurong , Bai, Xueyuan , Xie, Yuansheng, Yu, Hongyu, Wei, Kai, Zhang, Yingjie , Cai, Guangyan , Li, Xiaogang , Chen, Xiangmei

JCI Insight | September 18, 2019 | Volume: 4 | Issue: 18 | Pages: No page available

10.1172/jci.insight.127602 | PMID 31534052 Get It

Hereditary renal cystic diseases are characterized by defects in primary cilia of renal tubular epithelial cells and abnormality of tubular epithelium, which ultimately result in the development of renal cysts. However, the mechanism leading from abnormality of the tubular epithelium to cystogenesis is not well understood. In this report, we demonstrate a critical role for Robo2 in regulating epithelial development, including ciliogenesis, polarization, and differentiation. We found that Robo2 deficiency results in cystic kidneys, and the cyst cells showed defective cilia and polarity defects in tubular epithelium. The cyst cells, less than terminally differentiated, continue to proliferate. We further established that Robo2 works with p53 as well as polarity and ciliary proteins (Par3, PKCς, ZO-2, and Claudin-2) to regulate these processes. Robo2 binds to Baiap2 (also known as IRSp53) through the IRSp53/MIM homology domain in renal epithelial cells. This binding allows Robo2 to phosphorylate MDM2 at Ser166 via Baiap2 and maintain p53 homeostasis. Disruption of the Robo2-Baiap2 complex causes MDM2 to be subjected to dephosphorylation, leading to a high level of active p53, and initiated p53-mediated cellular senescence via p21 and decreased the expression of ZO-1, ZO-2, PKCς, Par3, and Claudin-2 proteins, resulting in defects in epithelial development, including ciliogenesis, polarization, and differentiation. Importantly, double knockout of Robo2 and p53 rescued all the epithelial defects in kidneys compared with those in Robo2 -knockout kidneys. Taken together, the present results demonstrate that Robo2 deficiency causes renal cystic disease, which is largely dependent on defective Robo2-Baiap2 integrated signaling in kidneys.