Am J Physiol Gastrointest Liver Physiol.
Soini T, Pihlajoki M, Andersson N, Lohi J, Huppert KA, Rudnick DA, Huppert SS, Wilson DB, Pakarinen MP, Heikinheimo M.
PMID: 29388792 | DOI: 10.1152/ajpgi.00362.2017
Biliary atresia (BA), a neonatal liver disease, is characterized by obstruction of extrahepatic bile ducts with subsequent cholestasis, inflammation, and progressive liver fibrosis. To gain insights into the pathophysiology of BA, we focused attention on GATA6, a transcription factor implicated in biliary development. Early in fetal development GATA6 expression is evident in cholangiocytes and hepatocytes, but by late gestation it is extinguished in hepatocytes. Utilizing a unique set of BA liver samples collected before and after successful portoenterostomy (PE), we found that GATA6 expression is markedly upregulated in hepatocytes of patients with BA compared to healthy and cholestatic disease controls. This upregulation is recapitulated in two murine models simulating bile duct obstruction and intrahepatic bile ductule expansion. GATA6 expression in BA livers correlates with two established negative prognostic indicators (age at PE, degree of intrahepatic bile ductule expansion) and decreases after normalization of serum bilirubin by PE. GATA6 expression in BA livers correlates with expression of known regulators of cholangiocyte differentiation ( JAGGED1, HNF1β, and HNF6). These same genes are upregulated after enforced expression of GATA6 in human hepatocyte cell models. In conclusion, GATA6 is a novel marker and a putative driver of hepatocyte-cholangiocyte metaplasia in BA and its expression in hepatocytes is downregulated after successful PE.
Journal of immunology (Baltimore, Md. : 1950)
Lai, CW;Bagadia, P;Barisas, DAG;Jarjour, NN;Wong, R;Ohara, T;Muegge, BD;Lu, Q;Xiong, S;Edelson, BT;Murphy, KM;Stappenbeck, TS;
PMID: 35868637 | DOI: 10.4049/jimmunol.2200278
The local microenvironment shapes macrophage differentiation in each tissue. We hypothesized that in the peritoneum, local factors in addition to retinoic acid can support GATA6-driven differentiation and function of peritoneal large cavity macrophages (LCMs). We found that soluble proteins produced by mesothelial cells lining the peritoneal cavity maintained GATA6 expression in cultured LCMs. Analysis of global gene expression of isolated mesothelial cells highlighted mesothelin (Msln) and its binding partner mucin 16 (Muc16) as candidate secreted ligands that potentially regulate GATA6 expression in peritoneal LCMs. Mice deficient for either of these molecules showed diminished GATA6 expression in peritoneal and pleural LCMs that was most prominent in aged mice. The more robust phenotype in older mice suggested that monocyte-derived macrophages were the target of Msln and Muc16. Cell transfer and bone marrow chimera experiments supported this hypothesis. We found that lethally irradiated Msln-/- and Muc16-/- mice reconstituted with wild-type bone marrow had lower levels of GATA6 expression in peritoneal and pleural LCMs. Similarly, during the resolution of zymosan-induced inflammation, repopulated peritoneal LCMs lacking expression of Msln or Muc16 expressed diminished GATA6. These data support a role for mesothelial cell-produced Msln and Muc16 in local macrophage differentiation within large cavity spaces such as the peritoneum. The effect appears to be most prominent on monocyte-derived macrophages that enter into this location as the host ages and also in response to infection.
Yoshida T, Takizawa N, Matsuda T, Yamada H, Kitada M, Tanaka S
PMID: 31949236 | DOI: 10.1038/s41598-019-57351-5
Adrenal cortex autotransplantation with ACTH stimulation may be an alternative therapy for patients with bilateral adrenalectomy to avoid adrenal crisis, but its underlying mechanism has not been elucidated. Previously, we detected Dhh upregulation in rat adrenocortical autografts after transplantation. Here, we investigated potential regulators such as Gata4, Gata6, Sry and Sox9 which affect Dhh transcription in adrenocortical autografts with or without ACTH stimulation. In ACTH-stimulated autografts, Gata4 and Gata6 were downregulated compared to control autografts. This response was linked to rDhh repression. A reporter assay using the upstream region of rDhh and a GATA binding motif revealed that rDhh promoters were significantly upregulated by co-transfection with Gata4 or Gata6 or both. Sry and Sox9 expression in autografts with or without ACTH stimulation were verified by PCR and RNAscope analyses. The ovarian differentiation factors Foxl2 and Rspo1 were also upregulated in the autografts. Gata4 and Gata6 were found to be significant factors in the regulation of rDhh expression and could be associated with adrenocortical autograft maintenance. Gonadal primordia with bipotential testicular and ovarian functions may also be present in these autografts.
Kokumai, T;Omori, Y;Ishida, M;Ohtsuka, H;Mizuma, M;Nakagawa, K;Chiho, M;Ono, Y;Mizukami, Y;Miura, S;Kume, K;Masamune, A;Morikawa, T;Unno, M;Furukawa, T;
| DOI: 10.1016/j.modpat.2023.100102
Relevant protein expression of GATA6, CK5, vimentin, and mucins using immunohistochemistry was assessed for predicting the prognosis and chemotherapy efficacy in pancreatic cancer (PC). The protein expression was examined in 159 PCs resected after neoadjuvant chemotherapy (NAC-PCs) with 120 matched biopsy specimens taken before NAC. KRAS mutations were assessed by digital PCR. NAC-PCs were classified by GATA6 expression initially and CK5 expression subsequently into four types, i.e., classical type (n = 22) showing GATA6-high (≧ 50%)/CK5-low (< 10%), hybrid type (n = 45) showing GATA6-high/CK5-high (≧ 10%), basal-like type (n = 53) showing GATA6-low (< 50%)/CK5-high (≧ 30%), and null type (n = 39) showing GATA6-low/CK5-low (< 30%), which resulted in a well-stratification of the patients’ prognosis. The classical type showed the most favorable prognosis, while the null type showed the worst prognosis (multivariate hazard ratio 3.56, 95% confidence interval (CI) 1.63−7.77, p = 0.0015). The hybrid and basal-like types were in between. The risk for hepatic recurrence was lower in the classical type than null (multivariate odds ratio (mOR) 0.18, CI 0.04−0.96, p = 0.0449) and basal-like (mOR 0.24, CI 0.05−1.16, p = 0.0750) types. In contrast, the risk for loco-regional recurrence was higher in classical type than the basal-like type (mOR 5.03, CI 1.20−21.1, p = 0.0272). The hybrid type was subclassified into transition and co-expression patterns with different gastric mucin expression. Vimentin-high (≧ 10%, n = 30) in pre-NAC-PC tissues was associated with poor prognosis (p = 0.0256). Phenotypic transitions between pre- and post-NAC were common (73/120; 61%). PCs with NAC regression grades 2 and 3 showed a transition to poorer prognostic phenotypes (p = 0.0497). KRAS mutations were not associated with these phenotypes. In conclusion, GATA6 and CK5 immunohistochemical expression phenotypes may stratify the survival of NAC-PCs and reflect post-NAC phenotypic transitions associated with poor prognosis. Prompt evaluation of immunohistochemical phenotypes may contribute to designing a precision therapeutic strategy for PC patients.
CDK7 and MITF repress a transcription program involved in survival and drug tolerance in melanoma
Berico, P;Cigrang, M;Davidson, G;Braun, C;Sandoz, J;Legras, S;Vokshi, BH;Slovic, N;Peyresaubes, F;Gene Robles, CM;Egly, JM;Compe, E;Davidson, I;Coin, F;
PMID: 34296805 | DOI: 10.15252/embr.202051683
Melanoma cell phenotype switching between differentiated melanocytic and undifferentiated mesenchymal-like states drives metastasis and drug resistance. CDK7 is the serine/threonine kinase of the basal transcription factor TFIIH. We show that dedifferentiation of melanocytic-type melanoma cells into mesenchymal-like cells and acquisition of tolerance to targeted therapies is achieved through chronic inhibition of CDK7. In addition to emergence of a mesenchymal-type signature, we identify a GATA6-dependent gene expression program comprising genes such as AMIGO2 or ABCG2 involved in melanoma survival or targeted drug tolerance, respectively. Mechanistically, we show that CDK7 drives expression of the melanocyte lineage transcription factor MITF that in turn binds to an intronic region of GATA6 to repress its expression in melanocytic-type cells. We show that GATA6 expression is activated in MITF-low melanoma cells of patient-derived xenografts. Taken together, our data show how the poorly characterized repressive function of MITF in melanoma participates in a molecular cascade regulating activation of a transcriptional program involved in survival and drug resistance in melanoma.
Eroglu, E;Yen, CYT;Tsoi, YL;Witman, N;Elewa, A;Joven Araus, A;Wang, H;Szattler, T;Umeano, CH;Sohlmér, J;Goedel, A;Simon, A;Chien, KR;
PMID: 35550612 | DOI: 10.1038/s41556-022-00902-2
The contribution of the epicardium, the outermost layer of the heart, to cardiac regeneration has remained controversial due to a lack of suitable analytical tools. By combining genetic marker-independent lineage-tracing strategies with transcriptional profiling and loss-of-function methods, we report here that the epicardium of the highly regenerative salamander species Pleurodeles waltl has an intrinsic capacity to differentiate into cardiomyocytes. Following cryoinjury, CLDN6+ epicardium-derived cells appear at the lesion site, organize into honeycomb-like structures connected via focal tight junctions and undergo transcriptional reprogramming that results in concomitant differentiation into de novo cardiomyocytes. Ablation of CLDN6+ differentiation intermediates as well as disruption of their tight junctions impairs cardiac regeneration. Salamanders constitute the evolutionarily closest species to mammals with an extensive ability to regenerate heart muscle and our results highlight the epicardium and tight junctions as key targets in efforts to promote cardiac regeneration.
Aung KL, Fischer SE, Denroche RE, Jang GH, Dodd A, Creighton S, Southwood B, Liang SB, Chadwick D, Zhang A, O'Kane GM, Albaba H, Moura S, Grant RC, Miller JK, Mbabaali F, Pasternack D, Lungu IM, Bartlett JMS, Ghai S, Lemire M, Holter S, Connor AA, Moffitt
PMID: 29288237 | DOI: 10.1158/1078-0432.CCR-17-2994
Abstract
Purpose: To perform real-time whole genome sequencing (WGS) and RNA sequencing (RNASeq) of advanced pancreatic ductal adenocarcinoma (PDAC) to identify predictive mutational and transcriptional features for better treatment selection.Experimental Design:Patients with advanced PDAC were prospectively recruited prior to first-line combination chemotherapy. Fresh tumor tissue was acquired by image-guided percutaneous core biopsy for WGS and RNASeq. Laser capture microdissection was performed for all cases. Primary endpoint was feasibility to report WGS results prior to first disease assessment CT scan at 8 weeks. The main secondary endpoint was discovery of patient subsets with predictive mutational and transcriptional signatures.Results: Sixty-three patients underwent a tumor biopsy between December 2015 and June 2017. WGS and RNASeq were successful in 62 (98%) and 60 (95%), respectively. Genomic results were reported at a median of 35 days (range, 19-52 days) from biopsy, meeting the primary feasibility endpoint. Objective responses to first-line chemotherapy were significantly better in patients with the classical PDAC RNA subtype compared with those with the basal-like subtype (P = 0.004). The best progression-free survival was observed in those with classical subtype treated with m-FOLFIRINOX. GATA6 expression in tumor measured by RNA in situ hybridization was found to be a robust surrogate biomarker for differentiating classical and basal-like PDAC subtypes. Potentially actionable genetic alterations were found in 30% of patients.Conclusions: Prospective genomic profiling of advanced PDAC is feasible, and our early data indicate that chemotherapy response differs among patients with different genomic/transcriptomic subtypes.
Schiffmann LM, Loeser H, Jacob AS, Maus M, Fuchs H, Zhao Y, Tharun L, Essakly A, Iannos Damanakis A, Zander T, B�ttner R, Schr�der W, Bruns C, Quaas A, Gebauer F
PMID: 32075129 | DOI: 10.3390/cancers12020451
Dickkopf-2 (DKK2) has been described as Wnt/beta-catenin pathway antagonist and its expression is mediated by micro RNA-221 (miRNA-221). So far, there is only limited data characterizing the role of DKK2 expression in esophageal cancer. A tissue micro array of 192 patients with esophageal adenocarcinoma was analyzed immunohistochemically for DKK2, miRNA-221 expression by RNA scope, and GATA6 amplification by fluorescence in-situ hybridization. The data was correlated with clinical, pathological and molecular data (TP53, HER2, c-myc, GATA6, PIK3CA, and KRAS amplifications). DKK2 expression was detectable in 21.7% and miRNA-221 expression in 33.5% of the patients. We observed no correlation between DKK2 or miRNA-221 expression and clinico-pathological data DKK2 expression was correlated with TP53 mutations and amplification of GATA6. We did not detect a survival difference in dependence of DKK2 for the total cohort, however, in patients without neoadjuvant treatment DKK2 expression correlated with a prolonged survival (median overall-survival 202 vs. 55 months, p = 0.012) which turned opposite in patients that underwent neoadjuvant treatment. High amounts of miRNA-221 were in trend associated with a prolonged overall-survival (p = 0.070). DKK2 as a Wnt antagonist is associated with prolonged survival in patients without neoadjuvant treatment and changes its prognostic value to the contrary in patients after neoadjuvant therapy. The modulatory effects of neoadjuvant treatment in connection with DKK2 expression are not fully understood, but when considering DKK2 as a tumor marker, it is necessary to see it in the context of neoadjuvant therapy
Tu, M;Klein, L;Espinet, E;Georgomanolis, T;Wegwitz, F;Li, X;Urbach, L;Danieli-Mackay, A;Küffer, S;Bojarczuk, K;Mizi, A;Günesdogan, U;Chapuy, B;Gu, Z;Neesse, A;Kishore, U;Ströbel, P;Hessmann, E;Hahn, S;Trumpp, A;Papantonis, A;Ellenrieder, V;Singh, S;
| DOI: 10.1038/s43018-021-00258-w
A,B, Expression correlation analysis in 78 PDAC patient tumors12 [/articles/s43018-021-00258-w#ref-CR12] (E-MTAB-6134 [http://www.ebi.ac.uk/arrayexpress/experiments/E-MTAB-6134/]) with high tumor cellularity between cJUN and VIM (A) as well as GATA6 and VIM (B). RMA-normalized probe intensity values were plotted. A linear regression with 95% CI is shown in orange. Pearson’s correlation (_R_) and corresponding two-tailed _P_ value are indicated. C, Representative bright-field images of GCDX62 cells transduced with empty vector (EV) or cJUN overexpression (cJUN-OE) constructs. Morphology was monitored over several passages. D-F, RNA-seq analysis was performed on GCDX62 cells transduced with EV or cJUN-OE. n = 3 independent cultures. D, PCA plot. E,F, Enrichment plots for gene set enrichment analysis between cJUN-OE and EV samples for ‘classical’ and ‘quasi-mesenchymal’ PDAC13 [/articles/s43018-021-00258-w#ref-CR13] (E), as well as the top genes up- and downregulated following TNFα treatment in CLA (CAPAN1) cells (F). G, WB for indicated targets in CAPAN1 cells transduced with EV or cJUN-OE. Representative of n = 3 independent experiments. H, Representative bright-field images of CAPAN1 cells transduced with EV or cJUN-OE. Morphology was monitored over several passages. C,H, Scale bar: 200 µm. I,J, Trans-well invasion assay of CAPAN1 cells transduced with EV or cJUN-OE, showing representative DAPI staining of invaded cells (I) as well as quantification thereof (J). I, Scale bar: 100 µm. J, Data given as average counts per F.o.V., with means ± s.d. Unpaired, two-tailed Student’s t-test. n = 3 independent experiments. K-M, Mean cell viability ± s.d. at different concentrations of gemcitabine (K), oxaliplatin (L) and SN38 (M) in CAPAN1 cells transduced with EV or cJUN-OE. IC50 values for each drug are indicated. n = 3 independent experiments.
