Smitha Gowdara Prakash, Shenoy Sadhana, Narayan Thondikulam Venakataraman, Jayaram Ranjita
Senior Lecturer, Department of Oral Pathology, Rajarajeswari Dental College and Hospital , Bangalore, India .
Reader, Department of Oral Pathology, The Oxford Dental College, Hospital and Research centre , Bangalore, India .
J Clin Diagn Res. 2016 May;10(5):ZC52-7. doi: 10.7860/JCDR/2016/14380.7778. Epub 2016 May 1.
Microenvironment is crucial for the maintenance of cellular functions and tissue integrity suggesting that cancer-induced changes in the stroma may contribute to cancer invasion and its biological behaviour. One of the major constituent of the tumour stroma is myofibroblasts. Myofibroblasts are differentiated host fibroblasts that express α-Sma as cytoplasmic microfilaments. They are considered as one of the modified stromal component which in recent years have been thought to have a role in the invasion and aggressive behaviour of odontogenic tumours too.
To detect immunohistochemically the presence of myofibroblasts in solid/multicystic ameloblastoma and in unicystic ameloblastoma and to see if a relationship exists between the frequency and pattern of distribution of myofibroblasts and the behaviour of ameloblastomas.
Ten cases each of solid/multicystic ameloblastoma and unicystic ameloblastoma were stained immunohistochemically for vimentin, α-SMA and desmin. The frequency and pattern of distribution of myofibroblasts in the two study groups were analysed and then compared with clinical and radiographic features of pain and cortical perforation respectively.
Immunohistochemical reaction for α-SMA (alpha Smooth Muscle Actin) showed positive cells in the stroma of both solid/multicystic and unicystic ameloblastomas. The mean number of myofibroblasts was more in unicystic ameloblastoma (UA) compared to Solid/Multicystic Ameloblastoma (SMA). Myofibroblasts expression was dense and arranged in the form of fascicles with indistinct cell borders in one case of follicular ameloblastoma, two cases of plexiform ameloblastoma and in a focal area of one case of type 1UA. In all other cases where the expression was noted, the myofibroblasts were spindle in shape with distinct cell boundaries.
The results of the study indicate that myofibroblasts alone may not play a role in the behaviour of ameloblastomas. This calls for determining the role of various other stromal components in the biological behaviour of ameloblastomas. Our study could not establish a correlation between pattern of distribution of myofibroblasts and the behaviour of ameloblastomas.
微环境对于维持细胞功能和组织完整性至关重要，这表明癌症诱导的基质变化可能有助于癌症侵袭及其生物学行为。肿瘤基质的主要成分之一是肌成纤维细胞。肌成纤维细胞是分化的宿主成纤维细胞，其表达α-Sma作为细胞质微丝。它们被认为是一种经过修饰的基质成分，近年来也被认为在牙源性肿瘤的侵袭和侵袭性行为中起作用。
通过免疫组织化学检测实性/多囊性成釉细胞瘤和单囊性成釉细胞瘤中肌成纤维细胞的存在，并观察肌成纤维细胞的频率和分布模式与成釉细胞瘤行为之间是否存在关系。
对10例实性/多囊性成釉细胞瘤和10例单囊性成釉细胞瘤分别进行波形蛋白、α-SMA和结蛋白的免疫组织化学染色。分析两个研究组中肌成纤维细胞的频率和分布模式，然后分别与疼痛和皮质穿孔的临床及影像学特征进行比较。
α-SMA（α平滑肌肌动蛋白）的免疫组织化学反应显示实性/多囊性和单囊性成釉细胞瘤的基质中均有阳性细胞。与实性/多囊性成釉细胞瘤（SMA）相比，单囊性成釉细胞瘤（UA）中肌成纤维细胞的平均数量更多。在1例滤泡性成釉细胞瘤、2例丛状成釉细胞瘤和1例1型UA的一个局灶区域中，肌成纤维细胞表达密集，呈束状排列，细胞边界不清晰。在所有其他有表达的病例中，肌成纤维细胞呈纺锤形，细胞边界清晰。
研究结果表明，仅肌成纤维细胞可能在成釉细胞瘤的行为中不起作用。这就需要确定其他各种基质成分在成釉细胞瘤生物学行为中的作用。我们的研究未能建立肌成纤维细胞分布模式与成釉细胞瘤行为之间的相关性。
