Table 2: Characteristics of studies included in investigating prevalence of myofibroblasts in oral cancer

References		Year of publication		Journal of publication		Details of the study
Zidar et al17		2002		Oncology		Sample - n1 = 42 (resected larynx) n2 = 40 (laryngeal biopsies of epithelial hyperplastic lesions and squamous carcinoma-myofibroblast found exclusively in squamous carcinoma)
Barth et al18		2004		Virchows Arch		Sample - n = 39 (OSCC and tumor-free oral mucosa) 31 carcinomas showed increased stromal a SMA positive myofibroblast
Lewis et al19		2004		Br J Cancer		Sample - n = 25 (15 OSCC and 10 fibro epithelial hyperplasia) Myofibroblasts differentiation is commonly seen in the stroma of OSCC (11), particularly at the invasive front of the tumor, no a SMA positive myofibroblast in the connective tissue of fibroepithelial hyperplasia
Vered et al20		2005		Oral Oncol		Sample - n = 53, high frequency of stromal myofibroblast in known aggressive odontogenic lesion, such as odontogenic keratocyst parakeratinized type and solid ameloblastoma implies that myofibroblast can contribute to the biological behavior of these odontogenic lesions
Kellermann et al21		2007		Histopathology		Sample - n = 117, myofibroblast in the stroma of the oral carcinoma are associated with poor prognosis
Kellermann et al22		2008		Oral Oncol		60% of the OSCC contain myofibroblast in the stroma of the tumor During tumor invasion OSCC-derived TGF-p 1 promote fibroblast myofibroblast transdifferentiation and tumor cell proliferation can be induced by factors released from myofibroblast favoring tumor growth
Verad et al23		2009		Cancer Microenviron		Sample - n = 19 (pair matched-oral tongue SCC and metastatic tumor to regional lymph node), expression of cancer-associated fibroblast is common to both primary and metastatic SCC
Franz et al24		2009		Histochem Cell Biol		Sample - n = 152, Snail-positive cell in the stroma of OSCC invasive front without statistically significant correlation, histological grade, or nodal metastasis.
Kawashiri et al25		2009		Head Neck		Sample - n = 84, high level of stromal collagen fibers in invasive tumors, myofibroblast appearance increased with increasing tumor invasiveness with frequent lymph node metastasis
Etemad-Moghadam et al26		2009		J Oral Pathol Med		Sample - n = 70, presence of myofibroblast in the stroma of OSCC but not in dysplasia and normal mucosa
Franz et al27		2010		J Oral Pathol Med		Sample - n = 5, mediated by myofibroblast OSCC development is associated with a stromal upregulation of laminin isoform possibly contributing to a migration promoting microenvironment
Seifi et al28		2010		Asian Pac J Cancer Pre		v Sample - n = 54, increase in the number of myofibroblast and change in the distribution pattern occur during carcinogenesis signifying their role in tumor invasion characteristics
Sobral et al29		2011		Oral Oncol		Sample - n = 30, myofibroblast in the stroma of OSCC may influence proliferation and invasion
Salgueiredo-Giudice et al30		2011		Oral Surg Oral Med Oral Pathol Oral Radiol Endod		Sample - n = 3, demonstration of IHC profile of oral inflammatory myofibroblastic tumor along with morphological analysis reveals positive for calponin, vimentin, a-SMA, fibronectin
Angadi et al13		2011		J Oral Pathol Med		Sample - n = 85, statistically significant increase in the myofibroblast between early and advance stages was observed
Sridhara et al31		2013		J Oral Maxillofac Pathol		Sample - n = 10, a-SMA cases were more in the metastatic group than in the nonmetastatic tumor
Lucio et al32		2013		Braz J Otorhinolaryngol		Myofibroblasts are important components of the stroma for SCC
Angadi et al33		2014		Ada Odontol Scand		Sample - n = 65, (50-OSCC and histologically normal mucosa adjacent to OSCC, 15-control) significant co-relation was established for the presence of myofibroblast in the stroma of OSCC and HNMAOSCC. Myofibroblasts are early stromal change in the HNMAOSCC that highlights the possible role of myofibroblast as likely mediator for field cancerization
Routray et al34		2014		Oral Dis		Myofibroblast can arise locally from endothelial mesenchymal transformation at the invasive edge of the cancer leading to development of high-grade malignancies and poor prognosis
Pinisetti et al35		2014		J Oral Maxillofac Pathol		Myofibroblast in focal epithelial dysplasia and SCC revealed a higher number of myofibroblast in OSCC
Rao et al36		2014		J Clin Diagn Res		Sample n = 62 (41 - OSMF, 10 - OSMF with dysplasia and 11 - OSCC). Presence of myofibroblasts was significantly higher in OSCC
Luksic et al49		2015		Int J Oral Maxillofac Surg		Sample n = 152, myofibroblast proliferation was suggested to facilitate tumor invasion and distant metastasis
Guan et al50		2015		Histopathology		Immunohistochemically, significant difference was observed in a-SMA expression in between normal controls and adenoid cystic carcinoma. This study demonstrated presence of myofibroblasts in adenoid cystic carcinoma.
Jensen et al51		2015		J Oral Pathol Med		In this study, budding tumor cells had decreased expression of E-cadherin. Thus, it is suggested that budding tumor cells in OSCC is not dependent upon either myofibroblast or complete epithelial― mesenchymal transition.

OSCC: Oral squamous cell carcinoma; HNMAOSCC: Histologically normal mucosa adjacent to oral squamous cell carcinoma; IHC: Immunohistochemistry; SMA: Smooth muscle actin; OSMF: Oral submucous fibrosis