Identification of novel SHOX target genes in the developing limb using a transgenic mouse model

Deficiency of the human short stature homeobox-containing gene (SHOX) has been identified in several disorders characterized by reduced height and skeletal anomalies such as Turner syndrome, Léri-Weill dyschondrosteosis and Langer mesomelic dysplasia as well as isolated short stature. SHOX acts as a transcription factor during limb development and is expressed in chondrocytes of the growth plates. Although highly conserved in vertebrates, rodents lack a SHOX orthologue. This offers the unique opportunity to analyze the effects of human SHOX expression in transgenic mice. We have generated a mouse expressing the human SHOXa cDNA under the control of a murine Col2a1 promoter and enhancer (Tg(Col2a1-SHOX)). SHOX and marker gene expression as well as skeletal phenotypes were characterized in two transgenic lines. No significant skeletal anomalies were found in transgenic compared to wildtype mice. Quantitative and in situ hybridization analyses revealed that Tg(Col2a1-SHOX), however, affected extracellular matrix gene expression during early limb development, suggesting a role for SHOX in growth plate assembly and extracellular matrix composition during long bone development. For instance, we could show that the connective tissue growth factor gene Ctgf, a gene involved in chondrogenic and angiogenic differentiation, is transcriptionally regulated by SHOX in transgenic mice. This finding was confirmed in human NHDF and U2OS cells and chicken micromass culture, demonstrating the value of the SHOX-transgenic mouse for the characterization of SHOX-dependent genes and pathways in early limb development

Evaluation of a program for routine implementation of shared decision-making in cancer care: study protocol of a stepped wedge cluster randomized trial

Abstract Background Shared decision-making (SDM) has become increasingly important in health care. However, despite scientific evidence, effective implementation strategies, and a prominent position on the health policy agenda, SDM is not widely implemented in routine practice so far. Therefore, we developed a program for routine implementation of SDM in oncology by conducting an analysis of the current state and a needs assessment in a pilot study based on the Consolidated Framework for Implementation Research (CFIR). Based on these results, the main aim of our current study is to evaluate the process and outcome of this theoretically and empirically grounded multicomponent implementation program designed to foster SDM in routine cancer care. Methods We use a stepped wedge design, a variant of the cluster randomized controlled trial. The intervention to be implemented is SDM. Three participating clinics of one comprehensive cancer center will be randomized and receive the multicomponent SDM implementation program in a time-delayed sequence. The program consists of the following strategies: (a) SDM training for health care professionals, (b) individual coaching for physicians, (c) patient activation strategy, (d) provision of patient information material and decision aids, (e) revision of the clinics’ quality management documents, and (f) critical reflection of current organization of multidisciplinary team meetings. We will conduct a mixed methods outcome and process evaluation. The outcome evaluation will consist of four measurement points. The primary outcome is adoption of SDM, measured by the 9-item Shared Decision Making Questionnaire. A range of other implementation outcomes will be assessed (i.e., acceptability, readiness for implementing change, appropriateness, penetration). The implementation process will be evaluated using stakeholder interviews and field notes. This will allow adapting interventions if necessary. Discussion This study is the first large study on routine implementation of SDM conducted in German cancer care. We expect to foster implementation of SDM at the enrolled clinics. Insights gained from this study, using a theoretically and empirically grounded approach, can inform other SDM implementation studies and health policy developments, both nationally and internationally. Trial registration clinicaltrials.gov, NCT03393351. Registered 8 January 2018

Evaluation of a program for routine implementation of shared decision-making in cancer care: results of a stepped wedge cluster randomized trial

Background!#!Shared decision-making (SDM) is preferred by many patients in cancer care. However, despite scientific evidence and promotion by health policy makers, SDM implementation in routine health care lags behind. This study aimed to evaluate an empirically and theoretically grounded implementation program for SDM in cancer care.!##!Methods!#!In a stepped wedge design, three departments of a comprehensive cancer center sequentially received the implementation program in a randomized order. It included six components: training for health care professionals (HCPs), individual coaching for physicians, patient activation intervention, patient information material/decision aids, revision of quality management documents, and reflection on multidisciplinary team meetings (MDTMs). Outcome evaluation comprised four measurement waves. The primary endpoint was patient-reported SDM uptake using the 9-item Shared Decision Making Questionnaire. Several secondary implementation outcomes were assessed. A mixed-methods process evaluation was conducted to evaluate reach and fidelity. Data were analyzed using mixed linear models, qualitative content analysis, and descriptive statistics.!##!Results!#!A total of 2,128 patient questionnaires, 559 questionnaires from 408 HCPs, 132 audio recordings of clinical encounters, and 842 case discussions from 66 MDTMs were evaluated. There was no statistically significant improvement in the primary endpoint SDM uptake. Patients in the intervention condition were more likely to experience shared or patient-lead decision-making than in the control condition (d=0.24). HCPs in the intervention condition reported more knowledge about SDM than in the control condition (d = 0.50). In MDTMs the quality of psycho-social information was lower in the intervention than in the control condition (d = - 0.48). Further secondary outcomes did not differ statistically significantly between conditions. All components were implemented in all departments, but reach was limited (e.g., training of 44% of eligible HCPs) and several adaptations occurred (e.g., reduced dose of coaching).!##!Conclusions!#!The process evaluation provides possible explanations for the lack of statistically significant effects in the primary and most of the secondary outcomes. Low reach and adaptations, particularly in dose, may explain the results. Other or more intensive approaches are needed for successful department-wide implementation of SDM in routine cancer care. Further research is needed to understand factors influencing implementation of SDM in cancer care.!##!Trial registration!#!clinicaltrials.gov, NCT03393351 , registered 8 January 2018

Regulated genes in transgenic mice and validation of <i>Ctgf</i> as a target.

<p>(A): qRT-PCR using limb RNA (E12.5-E14.5) from wildtype (Wt) and transgenic littermates (Tg) (N = 8–10 for each stage). Measurements were carried out individually, in duplicates, and normalized to <i>Adam9</i> and <i>Sdha</i>. Relative normalized values are presented on the y-axis. Significances are indicated in each diagram by asterisks (*: <i>p</i>≤0.05, **: <i>p</i>≤0.01, ***: <i>p</i>≤0.001). Variations are indicated by the standard deviation (SD). In 7/8 candidates an upregulation was confirmed as significant in at least one embryonic stage. (B): nCounter analysis of <i>CTGF</i> and <i>SHOX</i> expression in NHDF and U2OS cells after transient transfections of <i>SHOX</i> and <i>p.Y141D</i>. <i>CTGF</i> is significantly downregulated in NHDF cells, whereas it is significantly upregulated in U2OS cells. Values on y-axis represent absolute counts of mRNA, normalized to <i>ADAM9</i>, <i>HPRT1</i> and <i>SDHA</i>. Significancies are indicated by asterisks. (C): <i>In situ</i> hybridization using a <i>Ctgf</i> antisense riboprobe on embryonic limbs from wildtype and <i>SHOX</i>-transgenic littermates (N = 8) at stage E12.5. In transgenic embryos, enhanced and distalized expression of <i>Ctgf</i> was detected in the middle part of the developing limbs.</p

Analysis of postnatal bone parameters of <i>Col2a1-SHOX</i>-transgenic mice.

<p>(A): Alcian Blue/Alizarin Red S staining at different developmental (E14.5, E18.5) and postnatal (P28) stages does not reveal apparent differences between transgenic and wildtype skeletal elements. (B): Postnatal <i>in vivo</i> time-course analysis of bone growth in 65 animals of two transgenic lines by μ-CT analysis. Tibiae and femora of wildtype and <i>Tg(Col2a1-SHOX)</i> littermates at the age of 4, 12 and 24 weeks were scanned, female and male individuals were evaluated separately. Total bone length, cortical bone thickness and bone volume do not show significant differences between wildtype and transgenic females or males. Some transgenic animals presented longer bones and weaker structures of the cortical bone in the subcartilaginous region (indicated in the μ-CT images). Other micromorphological parameters (bone mineral density (BMD), trabecular volume and thickness) showed no significant differences. Statistical analyses were performed using student's t-test. (C): hematoxilin and eosin (H&E) stainings of the growth plate in wildtype and transgenic tibiae. Consistent differences between wildtype and <i>Tg(Col2a1-SHOX)</i> adult growth plates (24 weeks of age) did not exist (N = 8), but some transgenic tibiae showed a buckling, and the columns of chondrocytes became shorter and were not strictly oriented in a parallel assembly compared to the wildtype (right image).</p

Analysis of <i>CTGF</i> as a direct transcriptional target of SHOX.

<p>(A): Genomic structure of the human <i>CTGF</i> region. ChIP-Seq analysis in ChMM cultures revealed an accumulation of Shox binding in the <i>Ctgf</i> promoter region (grey peaks), especially in a region 3–4 kb from the transcriptional start site (TSS) where an evolutionary conserved sequence (ECR) of 597 bp (human chr6:132317086-132318077) was identified (green bar). (B): Location of the pGL3 ECR and pGL3 ECR+ reporter constructs (grey bars) within the <i>CTGF</i> upstream region. The ECR+ construct encompasses the ECR and an upstream region including ATTA/TAAT motifs and palindromes. SHOX binding motifs (ATTA/TAAT sites and palindromes) in the <i>CTGF</i> 5′ region around the ECR are indicated by asterisks. Red bars represent the location of the generated oligonucleotides for EMSA. (C): Luciferase reporter gene assays in NHDF and U2OS cells. pcDNA4/TO <i>SHOX</i> was cotransfected with a luciferase reporter vector harbouring either the ECR or the ECR+ sequence. Transfections and measurements were carried out in triplicates. A significant activation in the luciferase activity was observed 24 h after <i>SHOX</i> transfection in NHDF cells using both reporter constructs (1.7-fold/2.5-fold with <i>p</i> = 0.02/0.007 for ECR/ECR+). In U2OS cells, an alteration was not observed for the ECR reporter, but a significant reduction was demonstrated for the ECR+ reporter construct (1.0-fold/2.8-fold with <i>p</i> = 0.1/0.003 for ECR/ECR+). (D): EMSA. The SHOX wildtype (Wt) and the mutant p.R153L proteins bind to oligonucleotides 1 and 2, whereas the defective proteins p.Y141D and p.A170P cannot. All fragments of oligonucleotides 1 and 2 containing an ATTA/TAAT site are sensitive to SHOX binding (1a–c, 2a–b). The fragment lacking this motif does not bind (oligonucleotide 2c). Using the SHOX-3 antibody (Ab), we demonstrate that the binding is SHOX-specific. (E): Immunohistochemistry performed on pubertal tibial growth plates. Staining was performed using preimmune serum as a negative control, SHOX antibody <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0098543#pone.0098543-Marchini1" target="_blank">[19]</a> and a CTGF-specific antibody. Both the SHOX and CTGF proteins were detected in growth plate chondrocytes.</p

Generation and expression analysis of <i>SHOX</i>-transgenic mice.

<p>(A): The <i>SHOXa</i> cDNA was tagged with a Lumio and SV40 Poly(A) sequence and cloned under the control of a murine <i>Col2a1</i> promotor/enhancer expression cassette. (B): Genotyping was performed using specific primers spanning the first 409 nucleotides of the <i>SHOXa</i> cDNA. No PCR product was detected in wildtype animals. (C):-Southern Blot analysis of the two transgenic lines (1 and 2) used for our investigations. Genomic DNA was digested with <i>BamHI</i>, <i>EcoRV</i> and <i>Hind III</i>. <i>BamHI</i> digestion results in a 1.3 kb fragment that corresponds to the Lumio/SV40-tagged <i>SHOX</i> cDNA, which was flanked by <i>BamHI</i> sites. The presence of only one signal per lane indicates a single integration site of the transgene. (D): Relative quantitative expression of <i>Col2a1</i> and <i>SHOXa</i> transcripts in limbs of wildtype and transgenic littermates (N = 5–8 per litter) at E12.5, E13.5 and E14.5. The expression of the transgene corresponds to the expression dynamics of <i>Col2a1</i>. <i>SHOX</i> levels are generally low with highest expression at E12.5. Values are variable among individual animals as indicated by the standard deviation (SD). (E): WISH of wildtype (Wt) and transgenic (Tg) embryonic limbs from E11.5-E14.5 (N = 20 for each stage). The transgene is weakly expressed in the developing limb at E11.5 and becomes defined around the cartilaginous anlagen at E12.5. From E13.5 onwards, the expression is mainly seen in the mesenchyme around the developing cartilage and in the perichondrium and decreases during later stages.</p