Andrew J Dalley1, Ahmad A Abdul Majeed1, Luke P Pitty2, Aidan G Major2, Camile S Farah3. 1. The University of Queensland, UQ Centre for Clinical Research, Brisbane, Queensland, Australia. 2. The University of Queensland, UQ Centre for Clinical Research, Brisbane, Queensland, Australia; The University of Queensland, School of Dentistry, Brisbane, Queensland, Australia. 3. The University of Queensland, UQ Centre for Clinical Research, Brisbane, Queensland, Australia; The University of Queensland, School of Dentistry, Brisbane, Queensland, Australia; The Australian Centre for Oral Oncology Research & Education, Brisbane, Queensland, Australia. Electronic address: camile@oralmedpath.com.au.
Abstract
OBJECTIVE: LGR5 is pivotal to oral cavity development and is implicated in epithelial malignancy whereby stimulation of LGR5 potentiates canonical Wnt signaling. This investigation tested our hypothesis of a correlation between LGR5 expression and the severity of oral epithelial dysplasia (OED) and oral squamous cell carcinoma (OSCC). STUDY DESIGN: Immunoreactive LGR5 protein expression was quantified in 342 tissue samples ranging in disease severity from normal through mild and moderate or severe OED to OSCC. RESULTS: LGR5 was restricted to the basal layers for normal tissues, projected to the stratum granulosum in severe dysplasia, intense in carcinoma nests of well-differentiated OSCC, but uniformly diffuse throughout poorly differentiated OSCC. Median LGR5 immunoreactivity index scores increased with disease severity: mild dysplasia = 1 < moderate or severe dysplasia = 2.5 < OSCC = 6. CONCLUSIONS: Inclusion of LGR5 in a panel of immunohistochemical biomarkers may improve identification of increased potential for malignancy in OED.
OBJECTIVE:LGR5 is pivotal to oral cavity development and is implicated in epithelial malignancy whereby stimulation of LGR5 potentiates canonical Wnt signaling. This investigation tested our hypothesis of a correlation between LGR5 expression and the severity of oral epithelial dysplasia (OED) and oral squamous cell carcinoma (OSCC). STUDY DESIGN: Immunoreactive LGR5 protein expression was quantified in 342 tissue samples ranging in disease severity from normal through mild and moderate or severe OED to OSCC. RESULTS:LGR5 was restricted to the basal layers for normal tissues, projected to the stratum granulosum in severe dysplasia, intense in carcinoma nests of well-differentiated OSCC, but uniformly diffuse throughout poorly differentiated OSCC. Median LGR5 immunoreactivity index scores increased with disease severity: mild dysplasia = 1 < moderate or severe dysplasia = 2.5 < OSCC = 6. CONCLUSIONS: Inclusion of LGR5 in a panel of immunohistochemical biomarkers may improve identification of increased potential for malignancy in OED.