Myofibroblasts and the Pathogenesis of Dupuytren’s Disease

Dupuytren’s disease is defined in Green’s Operative Hand Surgery as a condition of the hand characterised by the development of new tissue in the form of nodules and cords. Hand function can be significantly impaired and whilst the mainstay of treatment is surgery, recurrence has been reported in approximately 40-50% of patients. Myofibroblasts are central to the pathogenesis of Dupuytren’s disease although what regulates the myofibroblast phenotype during Dupuytren’s disease remains unclear. This thesis set out to test the hypothesis that the myofibroblast phenotype in Dupuytren’s disease is regulated by dermal fibroblasts and inflammatory mediators, specifically advanced glycation end products (AGEs) and TNF-α. I aimed to (1) systematically characterise the distribution of myofibroblasts (α-smooth muscle actin positive cells (α-SMA)) throughout excised Dupuytren’s tissue in relation to clinical disease activity (fixed flexion deformity and recurrence); (2) establish an in vitro contraction model to examine Dupuytren’s myofibroblasts and (3) use this model to examine how myofibroblast phenotype may be regulated by dermal fibroblasts and inflammatory mediators. I examined 103 Dupuytren’s cords and correlated the histological findings with the patient’s clinical flexion contracture and disease severity. Histological nodules, defined as a focal condensation of α-SMA positive cells, were seen in two-thirds of excised digital cord samples. These nodules were found in the vicinity of the proximal interphalangeal joints of the fingers. Nodules were more frequently observed in digits with less severe contractures and more active disease, whereas non-nodular cords were significantly associated with advanced digital contracture, reflecting end stage disease. Based on our current understanding of how myofibroblasts thrive on tension and contract against resistance, a mechanism for digital contraction has been proposed: nodules containing highly contractile myofibroblasts are present in active Dupuytren’s disease where digital flexion and extension of the interphalangeal joints is still possible and these nodules involute in end-stage disease, where severe contractures limit digital movement. In order to further study Dupuytren’s myofibroblasts, I also compared cell contraction in stress-released collagen gels with that in restrained gels using a culture force monitor (CFM). With the latter I was able to reliably measure cell-generated forces within restrained collagen gels. By using genetically matched sets of cells from patients, I also correlated cell contractility with α-SMA expression. Unlike control skin cells that initially contract and then plateau, Dupuytren’s myofibroblasts show continually increasing contractile force. Furthermore, increased contractility of Dupuytren’s myofibroblasts was reflected by higher α-SMA protein content and alignment of the α-SMA to stress fibres. Interestingly mRNA levels of α-SMA were similar in all matched cells, reflecting post-translational regulation of protein levels in myofibroblasts. Based on the observation that recurrence is significantly reduced following dermofasciectomy, I also tested whether dermal fibroblasts down-regulate the contractile Dupuytren’s myofibroblast. I co-cultured Dupuytren’s myofibroblasts and dermal fibroblasts and found that contractility of Dupuytren’s cells is not influenced by dermal cells. Therefore, reduced recurrence rate following dermofasciectomy may be due to other factors, such as more complete excision of affected tissue combined with reduced tension following application of full thickness skin grafts. Finally, recent studies have suggested that inflammatory mediators and AGE-RAGE interaction play a role in the development of the myofibroblast phenotype. I therefore used the CFM to examine the effect of AGEs and TNF-α on myofibroblast contractility. No difference in contractility of dermal fibroblasts was observed with AGEs, although a two-fold increase was seen with TNF-α. Overall, I have characterised the distribution of myofibroblasts in Dupuytren’s tissue and these data have led to interesting insights into disease pathogenesis. I have also established a reliable in vitro model for assessing Dupuytren’s myofibroblast phenotype and used this to demonstrate that whilst dermal fibroblasts do not downregulate myofibroblast activity, pro-inflammatory mediators may play a key role in modulating myofibroblast phenotype in this disease

Systematic review of non-surgical treatments for early Dupuytren’s disease

BACKGROUND: Dupuytren’s disease is a common fibrotic disorder of the palm characterized by the development of progressive flexion deformities in the digits, leading to significant functional impairment. Surgical excision remains the most common treatment. However, this is only indicated in patients with established contractures rather than those with early disease. Early disease is generally characterized by the presence of palmar nodules with limited or no contracture of the fingers. The ideal treatment would be directed at patients with early progressive disease to prevent future deterioration. Various non-surgical treatment modalities have been described but there is currently no systematic assessment of the role and efficacy of these treatments in patients with early disease. METHODS: Using a PICOS analysis we reviewed publications of studies of patients with early disease who had received physical therapies, pharmacological treatment, or radiotherapy. Following PRISMA guidelines titles and abstract were screened using predefined criteria to identify those reporting outcomes specifically relating to the treatment of early disease. In the absence of a definition of early disease studies were included if early DD was described clinically, with digital contractures not exceeding 30°, Tubiana grades N to 1, and which reported identifiable data. Studies were excluded if data for early DD patients could not be extracted for analysis. RESULTS: In this systematic review, 26 studies were identified and analyzed to evaluate the effect of pharmacological therapy (n = 11), physical therapy (n = 5) and radiotherapy (n = 10) on early Dupuytren’s disease. The studies comprised 20 case series, 1 cohort study with the remainder reporting case studies. All publications were graded level of evidence 4 or 5 assessed using the Oxford Centre for Evidence Based Medicine grading. Narrative descriptions of the data are presented. CONCLUSIONS: Physical therapies were the most robustly assessed, using objective measures but the studies were under powered, providing insufficient evidence of efficacy. Intralesional steroid injection and radiotherapy appeared to lead to softening of nodules and to retard disease progression but lacked rigorous evaluation and studies were poorly designed. There is an urgent need for adequately powered double blinded randomized trials for this common disorder which affects 4 % of the population. TRIAL REGISTRATION: The protocol was registered (CRD42015008986 16 November 2015) with the PROSPERO international prospective register of systematic reviews. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12891-016-1200-y) contains supplementary material, which is available to authorized users

The impact of immediate breast reconstruction on the time to delivery of adjuvant therapy: the iBRA-2 study

Background: Immediate breast reconstruction (IBR) is routinely offered to improve quality-of-life for women requiring mastectomy, but there are concerns that more complex surgery may delay adjuvant oncological treatments and compromise long-term outcomes. High-quality evidence is lacking. The iBRA-2 study aimed to investigate the impact of IBR on time to adjuvant therapy. Methods: Consecutive women undergoing mastectomy ± IBR for breast cancer July–December, 2016 were included. Patient demographics, operative, oncological and complication data were collected. Time from last definitive cancer surgery to first adjuvant treatment for patients undergoing mastectomy ± IBR were compared and risk factors associated with delays explored. Results: A total of 2540 patients were recruited from 76 centres; 1008 (39.7%) underwent IBR (implant-only [n = 675, 26.6%]; pedicled flaps [n = 105,4.1%] and free-flaps [n = 228, 8.9%]). Complications requiring re-admission or re-operation were significantly more common in patients undergoing IBR than those receiving mastectomy. Adjuvant chemotherapy or radiotherapy was required by 1235 (48.6%) patients. No clinically significant differences were seen in time to adjuvant therapy between patient groups but major complications irrespective of surgery received were significantly associated with treatment delays. Conclusions: IBR does not result in clinically significant delays to adjuvant therapy, but post-operative complications are associated with treatment delays. Strategies to minimise complications, including careful patient selection, are required to improve outcomes for patients

Additional file 1: of Systematic review of non-surgical treatments for early Dupuytren’s disease

Search strategy and Search terms using PICOS analysis. (DOC 31 kb

Additional file 3: of Systematic review of non-surgical treatments for early Dupuytren’s disease

Study eligibility screening sheet. (DOC 26 kb

ERRATUM Open Access Erratum to: Thrombospondin 1 is a key mediator

of transforming growth factor b-mediated cell contractility in systemic sclerosis via a mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK)-dependent mechanis