"Loss of polarity of basal cells" - The term revisited in the light of genomics.

The concept of polarity in development, homeostasis and pathological alteration of tissues has emerged as an interesting aspect of the concerned biology. The epithelial cells exhibit apicobasal polarity which is maintained by Crumbs complex located at apical region of tight junction, 'PAR' complex at sub-apical region of tight junction and Scribble complex at adherens junction. Any functional perturbation of these proteins cause alteration of normal epithelial physiology en-route to epithelial pathology. In this maiden scientific exercise, we have tried to explore the association of expression of cell polarity proteins in OPMD and OSCC. Here, we have chosen DLG1 as a representative of polarity protein. RNA was isolated from the tissue samples. Then cDNA was prepared by RTPCR technique. qPCR was performed on cDNA samples. Expression data was analysed on the basis of Ct values. Paired t-test was performed with normalized Ct values of disease and normal tissue to determine whether there was any significant difference in expression between them. The statistical tests were done using SPSS software. Results of this study reflected increase in DLG1 expression in high grade dysplasia. There was no significant alteration in expression of DLG1 in WDSCC where there is formation of cluster of neoplastic cells ultimately producing epithelial islands and keratin pearls. But, in case of MDSCC, when the same neoplastic cells keep on invading with minimal keratin pearl formation, they again gain the mesenchymal character in full potential. And this phenomenon supports the upregulation of DLG1 in MDSCC in our study.

First case report of tongue squamous cell carcinoma in a neurofibromatosis type 1 patient and review of pathogenesis of carcinoma in neurofibromatosis type 1.

Neurofibromatosis type 1 (NF1), also known as von Recklinghausen's disease, is a type of genodermatoses having an autosomal dominant inheritance pattern and is recently considered as a RASopathy. Such patients are very much prone to develop mesenchymal tumors. However, carcinomas are quite rare in NF1 patients. This case study is the first case of oral squamous cell carcinoma (SCC) in tongue of an NF1 patient. A 35-year-old male reported to the Department of Oral Pathology in a tertiary care center with a chief complain of a painful ulcer on tongue for last 1 month. For confirmation of diagnosis of NF1, the "Diagnostic Criteria for Neurofibromatosis Type 1" was followed. Biopsied specimen of the tongue lesion was examined under microscope and histopathological features were suggestive of infiltrating SCC. Immunohistochemistry with Pan CK and beta-catenin was positive. RASopathy, WNT-beta-catenin pathway alteration, heat shock factor 1 production, and miRNA activity are investigated to explain the pathogenesis of malignancies in NF1 patients. In this first case of tongue SCC, we have found out the altered WNT-beta-catenin pathway.

Study of Caspase 8 mutation in oral cancer and adjacent precancer tissues and implication in progression.

It is hypothesized that same driver gene mutations should be present in both oral leukoplakia and cancer tissues. So, we attempted to find out mutations at one of the driver genes, CASP8, in cancer and adjacent leukoplakia tissues. Patients (n = 27), affected by both of cancer and adjacent leukoplakia, were recruited for the study. Blood and tissue DNA samples were used to identify somatic mutations at CASP8 by next generation sequencing method. In total, 56% (15 out of 27) cancer and 30% (8 out of 27) leukoplakia tissues had CASP8 somatic mutations. In 8 patients, both cancer and adjacent leukoplakia tissues, located within 2-5 cm of tumor sites, had identical somatic mutations. But, in 7 patients, cancer samples had somatic mutations but none of the leukoplakia tissues, located beyond 5cm of tumor sites, had somatic mutations. Mutated allele frequencies at CASP8 were found to be more in cancer compared to adjacent leukoplakia tissues. This study provides mutational evidence that oral cancer might have progressed from previously grown leukoplakia lesion. Leukoplakia tissues, located beyond 5cm of cancer sites, were free from mutation. The study implies that CASP8 mutation could be one of the signatures for some of the leukoplakia to progress to oral cancer.

A novel mutation at ANTXR1 in an Indian patient with growth retardation-alopecia-pseudoanodontia-optic atrophy syndrome.

OBJECTIVE: Growth retardation-alopecia-pseudoanodontia-optic atrophy (GAPO) syndrome (Online Mendelian Inheritance in Man [OMIM] ID 230740) is one of the rarest autosomal recessive syndromes. It is characterized by many phenotypes, including wide anterior fontanel, frontal bossing of the face, depressed nasal bridge, along with the 4 classic phenotypes contained in the name of the syndrome. Recent reports identified nonsense, missense, and splicing mutations at different exons of ANTXR1 responsible for GAPO syndrome in patients from different ethnic populations. Here, we are reporting a mutation at ANTXR1 in an Indian patient with GAPO syndrome. STUDY DESIGN: We describe an inherited mutation at ANTXR1 in a 6-year-old Indian boy with GAPO syndrome. RESULTS: Genomic DNA from the patient with the GAPO syndrome and his family members were screened for previously reported mutations at ANTXR1 by sequencing. Novel homozygous and heterozygous mutations in exon-3 of ANTXR1 (c.265 G > A, p.Gly89 Arg) were identified in the patient and in other members of the family, respectively. However, no mutated allele was identified in genomic DNA from unrelated healthy individuals. Bioinformatic analysis by different tools predicted the deleterious, damaging, or aberrant splicing effect of mutation on the protein. CONCLUSIONS: Functional inefficiency of ANTXR1 as a result of mutation might have led to GAPO syndrome.

A retrospective study of oral lichen planus in paediatric population.

AIM: Well documented cases of oral lichen planus, a cell mediated immune condition is infrequently reported in paediatric population. This study was undertaken to obtain epidemiological data retrospectively and also to explore the possibility of any association that might exist among the clinical and histopathological features in paediatric patients suffering from oral lichen planus. SUBJECTS AND METHODS: A retrospective study was carried out on 22 patients, younger than 18 years with clinical and histopathological diagnosis of oral lichen planus over a period of 14 years. The clinical characteristics and histopathological features were observed. The statistical analysis of the data was performed using Statistical Analysis Software (SAS), Version 9.1. RESULTS: Analysis of data of 22 patients revealed that the average age of patient is 15.18 years with equal male and female predilection. The most common site is buccal mucosa (50%) and most frequent clinical form is erosive (63.64%). Focusing on the histopathological findings, parakeratosis was found in 86.36% of the cases, acanthosis in 63.64% of cases, moderate basal cell degeneration was identified in 63.64% of cases and dense lymphocytic infiltration at juxtaepithelial connective tissue region was found in 59.09% of cases. CONCLUSIONS: Oral lichen planus in paediatric population is rare and appeared between 8 to 18 years of age. There is no significant gender predominance. The most common clinical form is erosive, manifesting mainly in buccal mucosa. Histopathological findings characteristic of oral lichen planus in paediatric patients include parakeratosis, acanthosis, liquefaction degeneration of basal cells and lymphocytic infiltration in the subepithelial layer.