OBJECTIVE: To investigate the role of S100A4 expression as an important component of the epithelial mesenchymal transition (EMT) program in oral squamous cell carcinoma (OSCC).
MATERIAL AND METHODS: S100A4 protein expression was assessed semi-quantitatively by immunohistochemistry in 47 histologically confirmed cases of oral squamous cell carcinoma (OSCC) and 10 normal oral mucosal biopsies. The association between the S100A4 overexpression and the aggressive features of OSCC were analyzed by X2 test.
RESULTS: Moderate to strong cytoplasmic expression of S100A4 was observed in 30 out of 47 specimens of OSCC (64%). Overexpression of S100A4 was significantly associated with the clinical stage, lymph node involvement, metastases, pattern of invasion and recurrence (p<0.05).
CONCLUSION: S100A4 expression represents an important biomarker of prognostic significance that may be used to identify a subset of patients at high risk of invasion and metast.
MATERIALS AND METHODS: Immunohistochemical analysis of 60 thyroidectomy specimens (10 hyperplastic nodules, 14 follicular adenomas and 36 malignant thyroid neoplasms) was carried out. The extent and intensity of HBME-1, CK19, and S100 immunoreactivity was assessed in each case.
RESULTS: HBME-1 positivity was noted in 86.1% of malignant cases while the majority of the benign lesions were negative. Diffuse strong CK19 positivity was documented in 27/31 papillary carcinoma whereas all cases of follicular carcinoma and medullary carcinoma were negative. Most of the hyperplastic nodules and follicular adenomas were also CK19 negative, although focal weak staining was noted in a few cases. S100 was positive only in medullary carcinoma. HBME-1 was most sensitive (86.1%) and specific (87.5%) in distinguishing between benign and malignant thyroid lesions. The diagnostic accuracy was further increased when HBME-1 was used simultaneously with CK19/S100/CK19+S100. The sequential use of HBME-1 and CK19 also proved beneficial in discriminating between the various follicular-patterned thyroid lesions.
CONCLUSION: HBME-1 immunolabeling suggests malignancy, whereas strong diffuse CK19 positivity substantiates papillary differentiation. The utilization of these markers (alone or in combination) along with histomorphological evaluation is helpful in the differential diagnosis. S100 has minimal utility in this regard.
MATERIALS AND METHODS: Sciatic nerve gap of 15 mm was created in six adult female Sprague-Dawley rats and implanted with PLGA seeded with OECs. The nerve regeneration was assessed electrophysiologically at 2, 4 and 6 weeks following implantation. Histopathological examination, scanning electron microscopic (SEM) examination and immunohistochemical analysis were performed at the end of the study.
RESULTS: Nerve conduction studies revealed a significant improvement of nerve conduction velocities whereby the mean nerve conduction velocity increases from 4.2 0.4 m/s at week 2 to 27.3 5.7 m/s at week 6 post-implantation (P < 0.0001). Histological analysis revealed presence of spindle-shaped cells. Immunohistochemical analysis further demonstrated the expression of S100 protein in both cell nucleus and the cytoplasm in these cells, hence confirming their Schwann-cell-like property. Under SEM, these cells were found to be actively secreting extracellular matrix.
CONCLUSION: Tissue-engineered PLGA conduit seeded with OECs provided a permissive environment to facilitate nerve regeneration in a small animal model.