ABSTRACT
Background: Oral squamous cell carcinoma (OSCC) is the most common oral malignancy, representing up to 80-90% of all malignant neoplasms of the oral cavity. It results from the multistep accumulation of heterogeneous genetic changes. Important risk factors for OSCC include the use of tobacco or betel quid chewing, alcohol consumption, human papillomavirus and poor nutrition. E-Cadherin as a tumour suppressor gene sets a threshold for Wnt/ß-catenin signalling. When expression of E-Cadherin is lost, potentiation of Wnt signalling pathway occurs leading to loss of cell-cell adhesion. The cyclin D1 gene (CCND1) located on chromosome 11q13 encodes a nuclear protein that is the regulatory subunit of Cdk-4 and Cdk-6. Cyclin D1 plays a major role in cell cycle transition from G1 to S phase by contributing to inactivation of the retinoblastoma gene product, and overexpression of CCND1 has been reported in 35-40% cases of OSCC. Aim: Considering this, we decided to evaluate and compare the expression of CE-Cadherin and Cyclin D1 in different grades of OSCC. Materials and Methods: A retrospective study was carried out on 60 formalin-fixed paraffin embedded tissue blocks comprising of 20 cases of well-differentiated OSCC, 20 cases of moderately differentiated OSCC and 20 cases of poorly differentiated OSCC. Diagnosed (using H and E), with oral mucosa taken as control. Results: There was downregulation of E-Cadherin and overexpression of Cyclin D1 in increasing grades of OSCC and the difference was statistically significant. E-Cadherin was localised to membranous and shifted to cytoplasm as the grade worsened. Cyclin D1 was localised to nuclei of cells and the expression was seen more at the peripheral portions of tumour islands depicting the proliferative activity of tumour front. Conclusion: The study revealed a good prognostic role of both E-Cadherin and Cyclin D1 in OSCC. The markers can be used for prognostic as well as therapeutic purposes.
ABSTRACT
Trichoderma is the most commonly used fungal biocontrol agent throughout the world. In the present study, various Trichoderma isolates were isolated from different vegetable fields. In the isolated microflora, the colony edges varied from wavy to smooth. The mycelial forms were predominantly floccose with hyaline color and conidiophores among all the strains were highly branched. Based on morphological attributes, all the isolates were identified as Trichoderma harzianum. The molecular identification using multilocus sequencing ITS, rpb2 and tef1α, genes further confirmed the morphological identification. The average chitinase activity varied from 1.13 units/mL to 3.38 units/mL among the various isolates, which increased linearly with temperature from 15 to 30 °C. There was an amplified production in the chitinase production in the presence of Mg+ and Ca2+ and Na+ metal ions, but the presence of certain ions was found to cause the down-regulated chitinase activity, i.e., Zn2+, Hg2+, Fe2+, Ag+ and K+. All the chitinase producing Trichoderma isolates inhibited the growth of tested pathogens viz., Dematophora necatrix, Fusarium solani, Fusarium oxysporum and Pythium aphanidermatum at 25% culture-free filtrate concentration under in vitro conditions. Also, under in vivo conditions, the lowest wilt incidence and highest disease control on Fusarium oxysporum was observed in isolate BT4 with mean wilt incidence and disease control of 21% and 48%, respectively. The Trichoderma harzianum identified in this study will be further used in formulation development for the management of diseases under field conditions.
