Worldwide, approximately 405 000 cases of oral cancer (OSCC) are diagnosed each year, with a rising incidence in many countries. Despite advances in surgery and radiotherapy, which remain the standard treatment options, the mortality rate has remained largely unchanged for decades, with a 5-year survival rate of around 50%. OSCC is a heterogeneous disease, staged currently using the TNM classification, supplemented with pathological information from the primary tumour and loco-regional lymph nodes. Although patients with advanced disease show reduced survival, there is no single pathological or molecular feature that identifies aggressive, early-stage tumours. We retrospectively analysed 282 OSCC patients for disease mortality, related to clinical, pathological, and molecular features based on our previous functional studies [EGFR, αvβ6 integrin, smooth muscle actin (SMA), p53, p16, EP4]. We found that the strongest independent risk factor of early OSCC death was a feature of stroma rather than tumour cells. After adjusting for all factors, high stromal SMA expression, indicating myofibroblast transdifferentiation, produced the highest hazard ratio (3.06, 95% CI 1.65-5.66) and likelihood ratio (3.6; detection rate: false positive rate) of any feature examined, and was strongly associated with mortality, regardless of disease stage. Functional assays showed that OSCC cells can modulate myofibroblast transdifferentiation through αvβ6-dependent TGF-β1 activation and that myofibroblasts promote OSCC invasion. Finally, we developed a prognostic model using Cox regression with backward elimination; only SMA expression, metastasis, cohesion, and age were significant. This model was independently validated on a patient subset (detection rate 70%; false positive rate 20%; ROC analysis 77%, p < 0.001). Our study highlights the limited prognostic value of TNM staging and suggests that an SMA-positive, myofibroblastic stroma is the strongest predictor of OSCC mortality. Whether used independently or as part of a prognostic model, SMA identifies a significant group of patients with aggressive tumours, regardless of disease stage.
Oral submucous fibrosis (OSF) is a premalignant, fibrosing disorder of the mouth, pharynx, and oesophagus, with a malignant transformation rate of 7-13%. OSF is strongly associated with areca (betel) nut chewing and worldwide, over 5 million people are affected. As αvβ6 integrin is capable of promoting both tissue fibrosis and carcinoma invasion, we examined its expression in fibroepithelial hyperplasia and OSF. αvβ6 was markedly up-regulated in OSF, with high expression detected in 22 of 41 cases (p < 0.001). We investigated the functional role of αvβ6 using oral keratinocyte-derived cells genetically modified to express high αvβ6 (VB6), and also NTERT-immortalized oral keratinocytes, which express low αvβ6 (OKF6/TERT-1). VB6 cells showed significant αvβ6-dependent activation of TGF-β1, which induced transdifferentiation of oral fibroblasts into myofibroblasts and resulted in up-regulation of genes associated with tissue fibrosis. These experimental in vitro findings were confirmed using human clinical samples, where we showed that the stroma of OSF contained myofibroblasts and that TGF-β1-dependent Smad signalling was detectable both in keratinocytes and in myofibroblasts. We also found that arecoline, the major alkaloid of areca nuts, up-regulated keratinocyte αvβ6 expression. This was modulated through the M(4) muscarinic acetylcholine receptor and was suppressed by the M(4) antagonist, tropicamide. Arecoline-dependent αvβ6 up-regulation promoted keratinocyte migration and induced invasion, raising the possibility that this mechanism may support malignant transformation. Over 80% of OSF-related oral cancers examined had moderate/high αvβ6 expression. These data suggest that the pathogenesis of OSF may be epithelial-driven and involve arecoline-dependent up-regulation of αvβ6 integrin.
When Colles first described his familiar fracture in 1814, he claimed that the injured limb would eventually regain â€oeperfect freedom in all its motions―. Though some would agree with such an observation (Smaill 1965), many would not (Grasby and Trick 1929;Mayer 1940; Bacorn and Kurtzke 1953; Golden 1963;Cole and Obletz 1966). Frequent attempts have therefore been made to identify, as early as possible, the factors which may lead to a poor result.A number of radiographic features have been regarded as important for prognosis, notably intra articular involvement (Eelma and McElfresh 1983), volar tilt (Rubinovich and Rennie 1983), dorsal tilt,
Basal cell carcinoma (BCC) is the most prevalent cancer in the Western world and its incidence is increasing. The pathogenesis of BCC involves deregulated Sonic hedgehog signaling, leading to activation of the Gli transcription factors. Most BCCs have a nodular growth pattern, and are indolent, slowgrowing, and considered ''low-risk'' lesions. In contrast, the ''high-risk'' morphoeic variant, which causes significant morbidity, has an infiltrative growth pattern, and is so-called because of its densely fibrous stroma. As AvB6 is capable of promoting both carcinoma invasion and fibrosis, we examined the expression of this integrin in BCCs and found that the morphoeic type showed significantly higher AvB6 expression than the nodular type (P = 0.0009). In order to examine the function of AvB6, we transfected the transcription factors Gli1 or Gli2 into NTERT, human keratinocytes to generate a BCC model. These cells expressed AvB6 and were invasive, although inhibition of AvB6 had no direct effect on cell invasion. However, the cells showed AvB6-dependent activation of transforming growth factor-B1, which induced transdifferentiation of human fibroblasts into myofibroblasts. Paracrine secretion of hepatocyte growth factor/scatter factor by these myofibroblasts promoted c-Met-dependent tumor invasion in both Transwell and three-dimensional organotypic assays. These experimental in vitro findings were confirmed using human clinical samples in which we showed that the stroma of morphoeic BCC is myofibroblast-rich compared with nodular BCC (P = 0.0036), that myofibroblasts express hepatocyte growth factor/scatter factor, and that morphoeic BCCs are strongly c-Met-positive. These data suggest that AvB6-dependent transforming growth factor-B1 activation induces both the infiltrative growth pattern and fibrotic stroma so characteristic of morphoeic BCC. [Cancer Res 2008;68(9):3295-303]
Vertebral compression fractures (VCFs) are the most prevalent fractures in osteoporotic patients. The classical conservative management of these fractures is through rest, pain medication, bracing and muscle relaxants. The aim of this paper is to review prospective controlled studies comparing the efficacy and safety of minimally invasive techniques for vertebral augmentation, vertebroplasty (VP) and balloon kyphoplasty (BKP), versus non-surgical management (NSM). The Fracture Working Group of the International Osteoporosis Foundation conducted a literature search and developed a review paper on VP and BKP. The results presented for the direct management of osteoporotic VCFs focused on clinical outcomes of these three different procedures, including reduction in pain, improvement of function and mobility, vertebral height restoration and decrease in spinal curvature (kyphosis). Overall, VP and BKP are generally safe procedures that provide quicker pain relief, mobility recovery and in some cases vertebral height restoration than conventional conservative medical treatment, at least in the short term. However, the long-term benefits and safety in terms of risk of subsequent vertebral fractures have not been clearly demonstrated and further prospective randomized studies are needed with standards for reporting. Referral physicians should be aware of VP/BKP and their potential to reduce the health impairment of patients with VCFs. However, VP and BKP are not substitutes for appropriate evaluation and treatment of osteoporosis to reduce the risk of future fractures.
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