Issue: Calls to change medical education have been frequent, persistent, and generally limited to alterations in content or structural re-organization. Self-imposed barriers have prevented adoption of more radical pedagogical approaches, so recent predictions of the 'inevitability' of medical education transitioning to online delivery seemed unlikely. Then in March 2020 the COVID-19 pandemic forced medical schools to overcome established barriers overnight and make the most rapid curricular shift in medical education's history. We share the collated reports of nine medical schools and postulate how recent responses may influence future medical education. Evidence: While extraneous pandemic-related factors make it impossible to scientifically distinguish the impact of the curricular changes, some themes emerged. The rapid transition to online delivery was made possible by all schools having learning management systems and key electronic resources already blended into their curricula; we were closer to online delivery than anticipated. Student engagement with online delivery varied with different pedagogies used and the importance of social learning and interaction along with autonomy in learning were apparent. These are factors known to enhance online learning, and the student-centered modalities (e.g. problem-based learning) that included them appeared to be more engaging. Assumptions that the new online environment would be easily adopted and embraced by 'technophilic' students did not always hold true. Achieving true distance medical education will take longer than this 'overnight' response, but adhering to best practices for online education may open a new realm of possibilities. Implications: While this experience did not confirm that online medical education is really 'inevitable,' it revealed that it is possible. Thoughtfully blending more online components into a medical curriculum will allow us to take advantage of this environment's strengths such as efficiency and the ability to support asynchronous and autonomous learning that engage and foster intrinsic learning in our students. While maintaining aspects of social interaction, online learning could enhance pre-clinical medical education by allowing integration and collaboration among classes of medical students, other health professionals, and even between medical schools. What remains to be seen is whether COVID-19 provided the experience, vision and courage for medical education to change, or whether the old barriers will rise again when the pandemic is over.

Medical Education Program Highlights Geisinger Commonwealth School of Medicine (GCSOM) was founded as The Commonwealth Medical College (TCMC) in 2009. Established by the community, without a parent university or sponsoring hospital system, the school collaborated with volunteer community faculty and local health care institutions to deliver the curriculum. From the beginning, the school has embraced a mission to serve the community and to replenish its physician workforce. It has been innovative in significant ways: The first medical school to use the longitudinal integrated clerkship (LIC) for the entire class Using active learning and the flipped classroom extensively, with lectures representing less than 23% of classroom time in the preclinical years Integrating community experiences, community health, and community service fully into the curriculum On January 1, 2017, the school integrated with Geisinger, a highly functioning, integrated health care delivery system, which immediately provided robust and stable clinical learning venues; access to over 1,600 clinician–educators to serve as faculty; and exposure to cutting-edge research and clinical innovation in informatics, data science, precision health, genomics, implementation science, and outcomes research. Geisinger’s existing graduate medical educational programs include over 450 learners in 48 accredited residency programs, providing enhanced learning for GCSOM students in an environment of cutting-edge innovations in education, research, and patient care. The Family-Centered Experience (FCE) is an integral part of GCSOM’s patient-centered approach to medical education. This program matches a pair of first-year medical students with a volunteer family from the community to teach them about the impact of illness on family life. Students follow their volunteer family for 2 years and participate in scheduled debriefing sessions with peer students and faculty regarding their experiences, observations, and lessons learned in an effort to foster student compassion and understanding. All first-year medical students complete longitudinal community health intervention projects (L-CHIPs) in collaboration with community partners to learn about community health research. The L-CHIP experience, anchored in the Physician and Society course, includes presentations on community-based participatory research, scientific method, research design, clinical and epidemiological research methods, research ethics, and biostatistics. Students work in small groups, to perform a literature review, interact with community partners, help develop and/or investigate a researchable question and proposal for community health intervention, and present a poster at a spring symposium. All third-year medical students are required to complete quality improvement community collaboratives to introduce the core competency of systems-based practice. Under the mentorship of QI staff in GCSOM teaching hospitals, students apply the principles of performance improvement, identify and analyze a health care delivery problem, and help develop and carry out a quality intervention in small groups. Through these projects, students learn to engage stakeholders to make changes in their routines that improve health care delivery and patient safety. A professional identity formation curriculum was developed to address explicitly the professionalism competency. It maps longitudinal identity growth with an ultimate goal of becoming a reflective practitioner by providing a system of academic coaching for students. This includes a referral process to the GCSOM Center of Learning Excellence focused on early identification of academic and professionalism issues. The process documents each student’s professional identity formation growth throughout medical school through the use of an ePortfolio. Curriculum Curriculum description See Supplemental Digital Appendix 1—Curriculum Schematic—at https://links.lww.com/ACADMED/A929. Curriculum changes since 2010 Initially, the third year was a 12-month LIC with brief “bursts” of inpatient experiences. Based on feedback from students and preceptors, the third year was redesigned in 2017 into a hybrid LIC/block curriculum that consists of 6 months of inpatient experience and 6 months of outpatient LIC experience. This redesign eliminated interruptions in the continuity experience and provided a more robust inpatient experience, which facilitates full student engagement on clinical teams for a total of 23 weeks as compared with the previous 10 burst weeks. In 2019, the Longitudinal Continuity Experience (LCE), with 1 half day per month in year 2, was launched as part of the Art and Practice of Medicine course. The LCE pairs students to outpatient clinic sites where they are expected to practice their clinical skills and learn to navigate the day-to-day operations of an outpatient practice, under the guidance of a GCSOM faculty physician preceptor. In 2017, a new 4-year interprofessional education (IPE) core curricular element was established. The IPE component introduces foundational concepts of IPE in the first 2 years through IPE exercises with nursing and pharmacy students, using a Team STEPPS model. Third-year IPE sessions include multiple health care learners and simulated patient scenarios. In the fourth year, all students complete a required 2-week IPE rotation on a highly functioning interprofessional team to learn about roles, responsibilities, and factors that enhance or hinder team function. All IPE sessions are aligned with Interprofessional Education Collaborative core competencies. In 2017, TCMC became GCSOM. This resulted in the realignment of the clinical campus structure around 3 Geisinger sites: North (Scranton), South (Wilkes-Barre), and Central (Danville). A fourth campus site had been established earlier in Sayre, Pennsylvania, in affiliation with the Guthrie Health System. In 2019, a fifth campus was established within AtlantiCare in Atlantic City, New Jersey. All sites follow a similar clinical training curriculum. Assessment The ACGME core competencies inform GCSOM’s MD program objectives. Each of the 6 competencies has subcompetencies that are measured using formative and summative feedback, objective structured clinical examinations (OSCEs), team-based learning, exams, essays, peer evaluations, and performance on national exams. See Supplemental Digital Appendix 2—Medical Education Program Objectives—at https://links.lww.com/ACADMED/A929. Pedagogy See Figure 1—Pedagogical approaches.Figure 1: Pedagogical approaches.Clinical experiences The sites used for the required rotations are primarily Geisinger or Guthrie network locations; however, students also rotate with GCSOM faculty at the Wilkes-Barre VA Medical Centers and at community-based sites for some clinical experiences. All GCSOM third-year learners complete a yearlong clerkship comprising a 6-month longitudinal integrated experience and discipline-specific block rotations in 6 core specialties. Half of the class begins the third year with longitudinal experience and half begins with block rotations, switching at midyear. GCSOM students spend a considerable amount of time at community sites during their clinical training, beginning with their first-year L-CHIP project and FCE, and continuing with their second-year LCE longitudinal outpatient experience. During the third-year LIC, students in the outpatient curriculum spend at least 1 half day weekly with an assigned physician in an ambulatory setting in each of the 6 core specialties, followed by intervals of 1–4 weeks in block inpatient rotations. Additional community experience is found in the 100 hours of required community service completed by each GCSOM student. GCSOM faced significant challenges in maintaining the original clinical campus structure as the health care environment in northeast Pennsylvania underwent structural change. Since the integration with Geisinger, we have established stable campuses and are in the process of renewing our medical education program and governance to match better the integrated health system. This integration has helped GCSOM establish early clinical exposure, enhancements in our required third- and fourth-year required rotations, and expansion of our elective rotation catalog. We are beginning a period of curriculum renewal in which we will further optimize our clinical education program by leveraging the strengths of the Geisinger and Guthrie health care systems. Curriculum Governance See Figure 2—Curricular governance committees.Figure 2: Curricular governance committees.Education Staff The Office of Academic Affairs, led by the vice dean for medical education, comprises 16 staff who support planning, implementation, evaluation, and oversight of the curriculum. The chair of the Department of Medical Education (DME) reports to the vice dean. The DME, with 43 faculty, is responsible for curriculum development and delivery in years 1 and 2. In addition, the department has 6 assistant chairs in core clinical disciplines (family medicine, internal medicine, obstetrics–gynecology, pediatrics, psychiatry, surgery) who are responsible for curriculum development, assessment, and comparability in the required clinical curriculum. Five regional associate campus deans lead the clinical campuses. Each campus associate dean is responsible for delivery of required clinical curriculum in years 3 and 4. Every campus has an assistant dean for student affairs and core clerkship directors, a regional education specialist (master’s-level educator responsible for monitoring student progress and implementing the curriculum), and support staff. See Figure 3—Medical education leadership.Figure 3: Medical education leadership.Each campus has a robust GME program that is administered by separate staff. Likewise, education for other learners outside of UME is administered through separate individuals. The UME mission at each campus has its own staff, as described above. In 2018, GCSOM combined its 2 medical school departments (basic and clinical science) into the single DME that represents all clinical and basic science disciplines at the medical school. Faculty Development and Support in Education The school has a robust faculty development program that is administered by the associate dean for faculty development. This includes a quarterly workshop in education topics at each campus, a yearlong medical education certificate program, and additional faculty development programs. Other campus-specific development activities include NBME-style question-writing workshops, narrative composition workshops, facilitator development, professional identity workshops, implicit bias training, and well-being/resiliency workshops. All faculty at GCSOM are evaluated based on teaching excellence (quantity and quality) and use of a scholarly approach in education and their level of scholarship (engagement). All faculty submit educational portfolios that include evidence of excellence and documentation of engagement (abstracts, workshops, presentations, seminars, posters, etc.) based on the AAMC’s Group on Educational Affairs criteria, including teaching, learner assessment, curriculum development, mentoring/advising, and educational leadership/administration. Regional Medical Campuses See Table 1—Regional Medical Campuses.Table 1: Regional Medical CampusesEducational experiences across sites Consistency of educational experiences across sites is monitored at quarterly intervals. Regional campus leadership and the assistant chairs for the 6 core disciplines are sent aggregated data that include shelf exam performance, preceptor assessments of student performance, OSCE scores, and clinical encounters and skills. This allows student progress and campus comparability to be evaluated and discussed in real time. The regional deans are also responsible for meeting with the hospital and clinical leadership within their campuses to ensure that the learning environment is appropriate for students. This is also monitored using a learning environment survey that is delivered annually to first- and third-year students. An online event-triggered learning environment form can also be submitted by students at any time during their education. Initiatives in Progress The Abigail Geisinger Scholars Program awards up to 10 students per class up to 4 years of tuition and fees in the form of a loan, which is forgiven upon completion of a service commitment as a Geisinger physician. The award recipient is obligated to practice as a Geisinger-employed physician upon completion of residency training. One year of service is required for each year of support, with a 2-year minimum commitment. Thus, participants who complete their obligation will have no tuition debt. This initiative was launched in the spring of 2019. The Geisinger Primary Care Scholars Program, launching in the spring of 2020, supports up to 40 students per class with full tuition and fees and a $2,000-per-month stipend in the form of a forgivable loan. Upon completion of residency training, the student will become a Geisinger-employed primary care physician (family medicine, medicine, medicine–pediatrics), providing 1 year of service for each year of support. The objective of this program is to create new regional primary care physicians who have no educational debt from pursuit of their MD degree. A 2020 curriculum renewal effort is currently gathering the talent of all stakeholders across our 2 health systems to create a curriculum that will produce practitioners who are ideally suited to practice medicine in a changing health care environment. Thus, the renewed curriculum will include themes that reflect strengths evident in our health care systems based on the following principles and foundational elements: Integration of basic and clinical sciences throughout the curriculum Establishment of signature, evidence-based pedagogies Creation of meaningful roles for students in the clinical environment with progressively increased levels of responsibility throughout training Explicit inclusion of professional development formation Service to the community Leveraging system and regional strengths to ensure curricular excellence Ensuring that graduates are prepared to become excellent residents

Goodman and Gilman’s The Pharmacological Basis of Therapeutics (GGPBT) has been a cornerstone in the education of pharmacists, physicians, and pharmacologists for decades. The objectives of this study were to describe and evaluate the 13th edition of GGPBT on bases including: (1) author characteristics; (2) recency of citations; (3) conflict of interest (CoI) disclosure; (4) expert evaluation of chapters. Contributors’ (N = 115) sex, professional degrees, and presence of undisclosed potential CoI—as reported by the Center for Medicare and Medicaid’s Open Payments (2013–2017)—were examined. The year of publication of citations was extracted relative to Katzung’s Basic and Clinical Pharmacology (KatBCP), and DiPiro’s Pharmacotherapy: A Pathophysiologic Approach (DiPPAPA). Content experts provided thorough chapter reviews. The percent of GGPBT contributors that were female (20.9%) was equivalent to those in KatBCP (17.0%). Citations in GGPBT (11.5 ± 0.2 years) were significantly older than those in KatBCP (10.4 ± 0.2) and DiPPAPA (9.1 ± 0.1, p < 0.0001). Contributors to GGPBT received USD 3 million in undisclosed remuneration (Maximum author = USD 743,718). In contrast, DiPPAPA made CoI information available. Reviewers noted several strengths but also some areas for improvement. GGPBT will continue to be an important component of the biomedical curriculum. Areas of improvement include a more diverse authorship, improved conflict of interest transparency, and a greater inclusion of more recent citations.

The active learning approach has been suggested to promote increased learning in science classes when compared to the traditional lecture‐based approach. The flipped classroom approach is one method that has recently gained popularity to implement active learning approaches within the classroom by encouraging student‐centered group learning and problem solving activities. While some studies report that flipped classroom experiences can improve student performance and produce favorable student perceptions, others report that these gains in performance are not consistent and that the positive effects from flipped pedagogy are short lived. In this study we compared learning outcomes and student perceptions between two, randomized, study arms that were exposed to either active learning or lecture style pedagogy before and after they were crossed over between the pedagogy styles. To ensure continuity of experience, demographics and GPA were similar in each group and they received the exact same material with the only difference being the pedagogy employed. Group A received flipped classroom pedagogy, while group B received traditional lecture pedagogy for four consecutive sessions at which time the groups were crossed over. After the cross over group A received traditional lecture pedagogy and group B received the flipped classroom pedagogy for four additional consecutive sessions. At the end of each session a five‐question evaluation quiz was given and no significant difference in quiz performance was observed between the flipped or lecture groups except that group B outperformed group A during the traditional arm of the study. No differences were observed when exam performance was compared. To assess students' attitudes about the flipped vs. lecture pedagogy, a previously validated Motivated Strategies for Learning Questionnaire (MSLQ) was utilized. A pre‐course survey, a midway‐survey and a post‐course survey was given. Findings suggest that while student confidence in their abilities was reduced initially, this recovered toward the end of the study. Taken together, flipped classroom approaches in this study did not have a significant difference on student performance or perception.

The extracellular matrix is the intricate scaffolding which surrounds and supports cells and helps to organize them into tissues and organs. The CCN family of matricellular proteins helps to regulate and modulate production, degradation, and remodeling of the extracellular matrix. In this chapter, we review the extracellular matrix of cartilage and bone, including an overview of chondrogenesis and skeletogenesis, and summarize the importance of the CCN proteins in establishment of the skeletal system. CCN proteins have both positive and negative regulatory roles in skeletal development, and their abnormal expression is related to the pathogenesis of several diseases observed in cartilage and bone that arise when inflammation or tissue injury becomes chronic, including fibrosis, arthritis, and cancer. Understanding the biological functions of the CCN proteins within this context offers opportunities for developing therapeutics by targeting CCN functions.

BACKGROUND:CCN2 acts as an anabolic growth factor to regulate osteoblast differentiation and function. CCN2 is induced by TGF-β1 and acts as a mediator of TGF-β1 induced matrix production in osteoblasts and Src is required for CCN2 induction by TGF-β1; however, the molecular mechanisms that control CCN2 induction in osteoblasts are poorly understood. AFAP1 binds activated forms of Src and can direct the activation of Src in certain cell types, however a role for AFAP1 downstream of TGF-β1 or in osteoblats is undefined. In this study, we investigated the role of AFAP1 for CCN2 induction by TGF-β1 in primary osteoblasts.RESULTS:We demonstrated that AFAP1 expression in osteoblasts occurs in a biphasic pattern with maximal expression levels occurring during osteoblast proliferation (~day 3), reduced expression during matrix production/maturation (~day 14-21), an a further increase in expression during mineralization (~day 21). AFAP1 expression is induced by TGF-β1 treatment in osteoblasts during days 7, 14 and 21. In osteoblasts, AFAP1 binds to Src and is required for Src activation by TGF-β1 and CCN2 promoter activity and protein induction by TGF-β1 treatment was impaired using AFAP1 siRNA, indicating the requirement of AFAP1 for CCN2 induction by TGF-β1. We also demonstrated that TGF-β1 induction of extracellular matrix protein collagen XIIa occurs in an AFAP1 dependent fashion.CONCLUSIONS:This study demonstrates that AFAP1 is an essential downstream signaling component of TGF-β1 for Src activation, CCN2 induction and collagen XIIa in osteoblasts.

Introduction: Palmitoylation describes the enzymatic attachment of the 16-carbon fatty acid, palmitate, to specific cysteines of proteins via a labile thioester bond. This post-translational modification increases the lipophilicity of the modified protein, thus regulating its subcellular distribution and function. The transfer of palmitate to a substrate is mediated by palmitoyl acyltransferases (PATs), while depalmitoylation is catalyzed by acyl protein thioesterases (APTs). Nearly one-third of the 23 genes that encode PATs are linked to human diseases, representing important targets for drug development. Areas covered: In this review, the authors summarize the recent technical advances in the field of palmitoylation and how they will affect our ability to understand palmitoylation and its relevance to human disease. They also review the current literature describing existing palmitoylation inhibitors. The aim of this article is to increase the awareness of the importance of palmitoylation in disease by reviewing the recent progress made in identifying pharmacological modulators of PATs/APTs. It also aims to provide suggestions for general considerations in the development of selective and potent PAT inhibitors. Expert opinion: Developing therapeutically useful pharmacological modulators of palmitoylation will require that they be developed within the context of well-characterized PAT/APT-related signaling systems. The successful development of potent, specific drugs in similarly complex systems suggests that development of useful drugs targeting PATs is feasible.

Connective tissue growth factor (CCN2; formerly CTGF) is a 38kDa, cysteine rich, extracellular matrix protein that belongs to the CCN family of proteins. CCN2 acts as an anabolic growth factor to regulate osteoblast differentiation and function. CCN2 is induced by TGF‐B1 and acts as a mediator of TGF‐B1 induced matrix production in osteoblasts; however, the molecular mechanisms that control CCN2 induction are poorly understood. In this study, we investigated the role of CCN2 promoter motifs involved in CCN2 induction by TGF‐B1 in primary osteoblasts. We used a combination of luciferase promoter reporter assays and gel shift studies to demonstrate the novel requirement of both the TGF‐B1 response element (TRE) and Smad binding element (SBE) for CCN2 promoter trans‐activation in osteoblasts. We propose that the TRE and SBE function as cognate motifs for CCN2 induction by TGF‐B1 in an osteoblast specific manner.Grant Funding Source: Supported by NIAMS

Selective estrogen receptor modulators (SERMs) are a diverse group of nonsteroidal compounds that function as agonists or antagonists for estrogen receptors (ERs) in a target gene-specific and tissue-specific fashion. SERM specificity involves tissue-specific expression of ER subtypes, differential expression of co-regulatory proteins in various tissues, and varying ER conformational changes induced by ligand binding. To date, the major clinical applications of SERMs are their use in the prevention and treatment of breast cancer, the prevention of osteoporosis, and the maintenance of beneficial serum lipid profiles in postmenopausal women. However, SERMs have also been found to promote adverse effects, including thromboembolic events and, in some cases, carcinogenesis, that have proven to be obstacles in their clinical utility. In this review, we discuss the mechanisms of SERM tissue specificity and highlight the therapeutic application of well-known and emergent SERMs.

Transcription factors (TFs) orchestrate multiple cellular processes through tight regulation via post-translational modifications (PTMs). Thus, decoding the combinations of PTMs should provide critical layer of information that can be integrated into highly specific cellular outputs to reveal a network of genes and their target-specific regulation. Protein modifications play a decisive role in various drug responses and eventually in prognosis for many life-threatening diseases, and recent studies demonstrate that TF-based drug designing must consider structural and functional changes due to PTMs, yet we are just beginning to grasp this enormity and the impact on normal development and disease pathophysiology.

Most of the biological effects of estrogens are mediated via the estrogen receptors (ERs) at the level of gene regulation. Recently, new information regarding the role of ERs in physiology, pathology and the mechanisms through which estrogens bring about these functions has emerged. The physiological effects of estrogen are manifested through two ER isoforms - ERα and ERβ - which display distinct regions of sequence homology. The crystal structures of these receptors bound to their specific ligands (e.g. agonists or antagonists) have revealed much about how ligand binding alters receptor structure/conformation and the interaction with coactivators or corepressors as well as how it determines the cellular response to a ligand. ERs are involved in the variety of physiological and pathological activities and different cells and tissues have shown divergent responses to these two receptor isoforms. The discovery of sub-isoforms of ER alpha and beta has further complicated our understanding of how the interaction between ERs and its ligands contribute to the development of disease. Nevertheless, continuing efforts in the study of ERs have helped us to more clearly define their role in disease and to develop novel, ER-targeted therapeutics.

Antiproliferative factor (APF) is a sialoglycopeptide elevated in the urine of patients with interstitial cystitis—a chronic, painful bladder disease. APF inhibits the proliferation of normal bladder epithelial and T24 bladder carcinoma cells in vitro by binding to cytoskeleton associated protein 4 (CKAP4) and altering the transcription of genes involved in proliferation, adhesion, and tumorigenesis; however, specific molecular mechanisms and effector genes that control APF's antiproliferative effects are unknown. In this study, we found that there was a 7.5‐fold upregulation of connective tissue growth factor (CTGF/CCN2) expression in T24 bladder carcinoma cells treated with APF, and Western blot revealed a dose‐dependent increase in CCN2 protein levels with secretion into the culture medium following APF treatment. CCN2 overexpression enhanced APF's antiproliferative activity while CCN2 knockdown by siRNA diminished it. Using a luciferase reporter construct, we found that APF treatment resulted in a 5‐fold activation of the CCN2 proximal promoter and that siRNA‐mediated knockdown of CKAP4 inhibited CCN2 upregulation. Additionally, we show that CKAP4 translocates to the nucleus and binds to the CCN2 proximal promoter in an APF‐dependent manner, providing evidence that CCN2 regulation by APF involves CKAP4 nuclear translocation and binding to the CCN2 promoter. NIH 1R03AR057193‐01; KIZ grant

Erythroblastosis virus E26 oncogene homologue 1 (Ets‐1) is the founding member of the Ets family of transcription factors that control cell proliferation, differentiation and ECM regulation. Ets‐1 participates in osteoblast differentiation; however, its mechanism of action remains largely undetermined. CTGF acts as an anabolic growth factor to regulate osteoblast differentiation and function. CTGF is induced by TGF‐β1 and mediates TGF‐β1 induced matrix production in osteoblasts, but the mechanisms that control CTGF induction by TGF‐β1 are not understood. This study investigates the role of Ets‐1 in CTGF induction by TGF‐β1 in osteoblasts. We demonstrate that: Ets‐1 expression is induced by TGF‐β1 treatment, that overexpression of Ets‐1 induces CTGF protein, and promoter activity similar to TGF‐β1 treatment alone and that Ets‐1 expression synergizes with TGF‐β1 to induce CTGF promoter activation and that Ets‐1 siRNA impaires CTGF expression. Bioinformatic analysis identified eight putative Ets‐1 binding motifs in the CTGF promoter. Using site‐directed mutagenesis, we found that mutation of EBE sites, especially in close proximity to the Smad binding element (SBE), had a more severe impact on CTGF expression suggesting that the Ets‐1 sites may cooperate with Smads to achieve CTGF expression following TGF‐β1 treatment in osteoblasts. This study was funded by NIAMS.

Background Ets-1 controls osteoblast differentiation and bone development; however, its downstream mechanism of action in osteoblasts remains largely undetermined. CCN2 acts as an anabolic growth factor to regulate osteoblast differentiation and function. CCN2 is induced by TGF-β1 and acts as a mediator of TGF-β1 induced matrix production in osteoblasts; however, the molecular mechanisms that control CCN2 induction are poorly understood. In this study, we investigated the role of Ets-1 for CCN2 induction by TGF-β1 in primary osteoblasts. Results We demonstrated that Ets-1 is expressed and induced by TGF-β1 treatment in osteoblasts, and that Ets-1 over-expression induces CCN2 protein expression and promoter activity at a level similar to TGF-β1 treatment alone. Additionally, we found that simultaneous Ets-1 over-expression and TGF-β1 treatment synergize to enhance CCN2 induction, and that CCN2 induction by TGF-β1 treatment was impaired using Ets-1 siRNA, demonstrating the requirement of Ets-1 for CCN2 induction by TGF-β1. Site-directed mutagenesis of eight putative Ets-1 motifs (EBE) in the CCN2 promoter demonstrated that specific EBE sites are required for CCN2 induction, and that mutation of EBE sites in closer proximity to TRE or SBE (two sites previously shown to regulate CCN2 induction by TGF-β1) had a greater effect on CCN2 induction, suggesting potential synergetic interaction among these sites for CCN2 induction. In addition, mutation of EBE sites prevented protein complex binding, and this protein complex formation was also inhibited by addition of Ets-1 antibody or Smad 3 antibody, demonstrating that protein binding to EBE motifs as a result of TGF-β1 treatment require synergy between Ets-1 and Smad 3. Conclusions This study demonstrates that Ets-1 is an essential downstream signaling component for CCN2 induction by TGF-β1 in osteoblasts, and that specific EBE sites in the CCN2 promoter are required for CCN2 promoter transactivation in osteoblasts.

Introduction: The role of lipophilicity in drug discovery and design is a critical one. Lipophilicity is a key physicochemical property that plays a crucial role in determining ADMET (absorption, distribution, metabolism, excretion, and toxicity) properties and the overall suitability of drug candidates. There is increasing evidence to suggest that control of physicochemical properties such as lipophilicity, within a defined optimal range, can improve compound quality and the likelihood of therapeutic success.Areas covered: This review focuses on understanding lipophilicity, techniques used to measure lipophilicity, and summarizes the importance of lipophilicity in drug discovery and development, including a discussion of its impact on individual ADMET parameters as well as its overall influence on the drug discovery and design process, specifically within the past 15 years.Expert opinion: A current review of the literature reveals a continued reliance on the synthesis of novel structures with increased potency, rather than a focus on maintaining optimal physicochemical properties associated with ADMET throughout drug optimization. Particular attention to the optimum region of lipophilicity, as well as monitoring of lipophilic efficiency indices, may contribute significantly to the overall quality of candidate drugs at different stages of discovery.

Connective tissue growth factor (CTGF) is a 38 kDa, cysteine rich, extracellular matrix protein composed of 4 domains or modules. CTGF has been shown to regulate a diverse array of cellular functions and has been implicated in more complex biological processes such as angiogenesis, chondrogenesis, and osteogenesis. A role for CTGF in the development and maintenance of skeletal tissues first came to light in studies demonstrating its expression in cartilage and bone cells, which was dramatically increased during skeletal repair or regeneration. The physiological significance of CTGF in skeletogenesis was confirmed in CTGF-null mice, which exhibited multiple skeletal dysmorphisms as a result of impaired growth plate chondrogenesis, angiogenesis, and bone formation/mineralization. Given the emerging importance of CTGF in osteogenesis and chondrogenesis, this review will focus on its expression in skeletal tissues, its effects on osteoblast and chondrocyte differentiation and function, and the skeletal implications of ablation or over-expression of CTGF in knockout or transgenic mouse models, respectively. In addition, this review will examine the role of integrin-mediated signaling and the regulation of CTGF expression as it relates to skeletogenesis. We will emphasize CTGF studies in bone or bone cells, and will identify opportunities for future investigations concerning CTGF and chondrogenesis/osteogenesis.

Abstract Due to the ability of glucocorticoids to prevent the growth and to cause apoptotic death of malignant cells, they are a mainstay of therapy for many lymphomas and leukemias. Glucocorticoid receptor (GR) mediates the biological effects of glucocorticoids at the level of gene regulation. To initiate transcription of target gene(s), GR interacts with its response element DNA, and/or with various coregulatory proteins. However, specific interaction surfaces of GR with its coregulators are not well understood. Consequently, precisely how transcription is regulated by GR is largely unknown. This is due, in part, to the lack of information about GR's major transactivation function region, AF1 located in the N-terminal domain. The major obstacle in determining the structure of AF1 has been due to its intrinsically disordered (ID) conformation, frequently found in the activation domains of many transcription factors, and it is believed that ID nature of these activation domains promote molecular recognition by creating large interaction surfaces suitable for interactions with their specific protein binding partners, which is a critical component of gene regulation by transcription factors. It has been hypothesized that conditional folding of these activation domains may be a prerequisite for their efficient interaction with specific coregulatory proteins, and subsequent transcriptional activity leading to the regulation of target gene(s). In this study, we tested whether a naturally occurring osmolyte, trehalose can promote functionally ordered conformation in the GR's major activation function domain, AF1, which is found to exist as an ID protein, and requires an efficient interaction with coregulatory proteins for optimal activity. Our data show that trehalose induces an ordered conformation in AF1 such that its interaction with steroid receptor coactivator-1 (SRC-1), a critical coregulator of glucocorticoid receptor's activity, is greatly enhanced. Our results may provide a mechanism for cell-type specificity of the effects of GR in gene regulation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4552. doi:10.1158/1538-7445.AM2011-4552