Laboratory of Translational Myology of the Interdepartmental Research Center of Myology, c/o Department of Biomedical Science, University of Padova, Italy.
Autoimmun Rev. 2010 Apr;9(6):449-53. doi: 10.1016/j.autrev.2009.12.005. Epub 2009 Dec 22.
The association between malignancy and autoimmune myositis has been largely described and confirmed by numerous epidemiological studies. The temporal relationship between the two pathologic conditions can vary: malignancy may occur before, at the same time or following the diagnosis of myositis. Beside these observations, the molecular mechanisms underlying this association are still unknown, even though it has been demonstrated a possible antigenic similarity between regenerating myoblasts and some cancer cell populations. To better identify peculiar histopathologic features common to cancer and myositis, we screened muscle biopsies from patients affected with polymyositis, dermatomyositis, myositis in association to cancer, and from patients affected with newly diagnosed cancer, but without myositis. Similarly to the histopatologic features that were observed in the muscle from myositis patients, especially in those with cancer associated myositis, in patients affected with malignancy at the clinical onset of disease we observed early sign of myopathy, characterized by internally nucleated and regenerating myofibers, most of them expressing the neural cell adhesion molecule. The hypothesis that in a particular subset of individuals genetically predisposed to autoimmunity, an initial subclinical tumor-induced myopathy may result in an autoimmune myositis, represents a further intriguing link behind the association of these two conditions.
恶性肿瘤与自身免疫性肌炎之间的关联已被大量的流行病学研究广泛描述和证实。这两种病理状况之间的时间关系可以不同:恶性肿瘤可能发生在肌炎之前、同时或之后。除了这些观察结果外,这种关联的分子机制仍不清楚,尽管已经证明再生肌细胞与某些癌细胞群之间可能存在抗原相似性。为了更好地识别癌症和肌炎共有的特殊组织病理学特征,我们筛选了患有多发性肌炎、皮肌炎、癌症相关肌炎的患者以及新诊断为癌症但无肌炎的患者的肌肉活检。与肌炎患者肌肉中观察到的组织病理学特征相似,尤其是在癌症相关肌炎患者中,在疾病发病时就患有恶性肿瘤的患者中,我们观察到早期肌病的迹象,其特征为肌纤维内有核和再生,其中大多数表达神经细胞黏附分子。在某些遗传易患自身免疫的个体亚群中,最初的亚临床肿瘤诱导的肌病可能导致自身免疫性肌炎,这是这两种情况关联背后的另一个有趣的联系。