ABSTRACT
BACKGROUND: Cyclin D1 is derived from PRAD1 or CCND1 gene located on chromosome 11q13 and it acts as a positive regulator of the cell cycle. In normal cells, cyclin D1 promotes progression through the G1 phase of the cell cycle. Over expression of cyclin D1 may lead to shortening of G1 phase, increased cell proliferation and reduced dependency on growth factors. Over expression of cyclin D1 has been reported in various tumors like esophageal carcinoma, hepatocellular carcinoma, lung carcinoma, and head and neck carcinoma. AIMS AND OBJECTIVES: The study was carried out to evaluate and compare the expression of Cyclin D1 in premalignant lesion and different grades of oral squamous cell carcinoma. MATERIALS AND METHODS: A total 75 histopathologically diagnosed cases of oral squamous cell carcinoma and oral premalignant lesions cases were evaluated immunohistochemically for cyclin D1 expression. RESULTS: We found that cyclin D1 protein expression was significantly altered from epithelial dysplasia to oral squamous cell carcinomas. CONCLUSION: Thus we can conclude that cyclin D1 may be a useful marker in the cases of oral precancer and cancer. It can also act as a potential target for molecular intervention studies in future.
ABSTRACT
Cancer stem cells (CSCs) have the ability to self-renew and are present in most tissues including breast, brain, lung, head and neck, prostates, testis, ovary, esophagus, colon and liver. Their origin is yet to be discovered though a series of hypotheses have been proposed in this regard. CSCs play a role in not only the creation of cancer but also its evolution, metastasis and recurrence. CSCs have an important role in cancer therapy and the resistance toward chemotherapeutic agents. This article reviews the characteristics of CSCs in terms of origin, methods of isolation and cancer therapy.
ABSTRACT
BACKGROUND: In large scale disasters associated with fire the damage caused by heat can make medico legal identification of human remains difficult. Teeth, restorations, and prostheses all of which are resistant to quite high temperatures and can be used as aids in identification process. AIM: Aim of the study was to investigate the macroscopic and microscopic changes of teeth and several dental filling materials exposed to a range of high temperature (200-800°C). Dental restorations include filling materials, crown, and bridges. MATERIALS AND METHODS: Restored and unrestored teeth were placed in a furnace and heated at a rate of 30°C/min and the effects of the predetermined temperatures 200, 400, 600, and 800°C were observed. Macroscopic and stereo microscope findings were observed. RESULTS: Our results showed that teeth and restorative materials resist higher temperatures than theoretically predicted and that even when a restoration is lost because of detachment or change of state, its ante-mortem presence can be confirmed and detected by stereo microscopic examination of the residual cavity. CONCLUSION: We further conclude that a reasonably reliable estimation of the temperature of exposure can be made from an analysis of the teeth and restorative materials.
