Document Type : Research Articles
Department of Oral Pathology and Microbiology, Manipal College of Dental Sciences Mangalore, Manipal Academy of Higher Education, India.
Department of Oral and Maxillofacial Surgery, Manipal College of Dental sciences, Mangalore, Manipal Academy of Higher Education, India.
Background and objectives: Laminin is a significant basement membrane (BM) glycoprotein, the expression of
which reflects BM integrity more precisely than do other ECM proteins. The present study aimed to evaluate laminin
expression in oral squamous cell carcinomas OSCC and to determine any associations with clinico-pathological
parameters (surgical margin status, lymph node involvement, survival and recurrence). Methods: Laminin expression was
evaluated in 31 cases of biopsy-proven OSCC by immunohistochemical staining and its association with prognosticators
and the Brynes grading system was determined by appropriate statistical analysis. Results: We observed a significant
increase in linear staining pattern (p<0.001) at the tumour-host interface in well-differentiated OSCC cases, in contrast
to poorly differentiated lesions which exhibited intense cytoplasmic expression within tumour cells. Higher cytoplasmic
laminin expression was seen in 33.3% of cases with involved surgical margins and 69.2% of cases with lymph node
metastasis (along with weak/absent staining of laminin around the tumour-host interface – Basement membrane around
tumour islands). Similarly, in 60% of the cases who died and in 81.8% of cases with tumour recurrence, moderately
intense cytoplasmic laminin expression was seen within tumour cells. On comparing variables of the Brynes grading
system, significant cytoplasmic expression of laminin was linked with mild inflammation (p<0.0016) and increased
mitotic activity (p<0.008). Conclusion: Based on these observations, immunohistochemical expression of laminin
might be useful to evaluate histological differentiation and aggressiveness of OSCCs.