Effect of dietary and topical Celecoxib on expression of bcl-2, bax, c-erb-B2 and Ki67 in carcinogen-induced tongue carcinoma in rat

The efficacy of photodynamic therapy in rat tongue dysplasia

Background

Photodynamic therapy (PDT) using 5-aminolevulinic acid (ALA) has previously shown promising results in cancerous cell destruction. The present study was conducted to evaluate the efficacy of this treatment option on oral epithelial dysplasia in Wistar rats. Furthermore, microscopic effects of systemic versus topical administration of ALA before laser illumination was assessed.

Material and Methods

Thirty male Wistar rats (200- 250 grams) were used in the present study. Tongue dysplasia was induced by a daily delivery of a 20 ppm solution of 4-nitroquinoline -1- oxide (4NQO) for 3 months. Then, rats were divided into 3 groups of 10 including, group 1 that was received systemic ALA-based PDT (30 mg/kg ALA), group 2 that was received topical ALA-based PDT (20% ALA solution) and group 3 (control) which was left untreated. Tongue specimens were fixed for histopathological evaluation and dysplasia was graded at microscopic level. Data was compared between various treatment groups using Mann Whitney test (p<0.05).

Results

The rate of atypical dysplastic cells was decreased significantly in both topical (p= 0.006) and systemic (p= 0.001) treatment groups compared to control group. Furthermore, systemic use of ALA resulted in a remarkable destruction of dysplastic cells compared to its topical application (p=0.045). Nevertheless, some evidence of muscle destruction was documented in systemic ALA group.

Conclusions

It seems that ALA mediated PDT is an effective treatment option for the destruction of dysplastic cells. However, the extent of this effect depends on the mode of ALA administration before light illumination.

Key words:Photodynamic therapy, 5-aminolevulinic acid, Dysplasia, Potentially malignant disorders.

Histological changes caused by meclofenamic acid in androgen-independent prostate cancer tumors: evaluation in a mouse model

Meclofenamic acid is a nonsteroidal anti-inflammatory drug that has shown therapeutic potential for different types of cancers, including androgen-independent prostate neoplasms. The antitumor effect of diverse nonsteroidal anti-inflammatory drugs has been shown to be accompanied by histological and molecular changes that are responsible for this beneficial effect. The objective of the present work was to analyze the histological changes caused by meclofenamic acid in androgen-independent prostate cancer. Tumors were created in a nude mouse model using PC3 cancerous human cells. Meclofenamic acid (10 mg/kg/day; experimental group, n=5) or saline solution (control group, n=5) was administered intraperitoneally for twenty days. Histological analysis was then carried out on the tumors, describing changes in the cellular architecture, fibrosis, and quantification of cellular proliferation and tumor vasculature. Meclofenamic acid causes histological changes that indicate less tumor aggression (less hypercellularity, fewer atypical mitoses, and fewer nuclear polymorphisms), an increase in fibrosis, and reduced cellular proliferation and tumor vascularity. Further studies are needed to evaluate the molecular changes that cause the beneficial and therapeutic effects of meclofenamic acid in androgen-independent prostate cancer.

Status of Ki-67, estrogen and progesterone receptors in various subtypes of intracranial meningiomas

Meningiomas are the most prevalent intracranial tumors in human being. Although, majority of these cases are of benign nature, malignant behavior might be seen in a number of patients. This study aimed to investigate the status of estrogen receptor, progesterone receptor and Ki-67 labeling index in different grades of surgical intracranial meningiomas. In this prospective study, 50 patients with intracranial meningiomas were operated at the department of neurosurgery, Tabriz Teaching Imam Reza Hospital; from February 2010 through January 2012. Tumor grade was determined histopathologically according to the World Health Organization (WHO) subtyping system. Status of estrogen and progesterone receptor, as well as the Ki-67 labeling index was determined by immunohistochemical approach and graded as 0 (absent), 1 (weak), 2 (moderate) and 3 (strong). The group of patients comprised 15 males (30%) and 35 females (70%) with a mean age of 71.76 +/- 10.20 (range: 49-87) years. WHO grades I, II and III tumors were reported in 68, 22 and 10% of the cases, respectively. Estrogen receptor, progesterone receptor and Ki-67 labeling index were detected in 20% (all grade 1), 98% (grade 1: 2%, grade 2: 22%, grade 3: 74%) and 38% (grade 1: 6%, grade 2: 22% and grade 3: 10%) of the cases, respectively. The rate of grade 1 estrogen receptor was significantly higher in WHO grade I tumors (29%) than in WHO grades II and III (zero for both, p = 0.02). Grade 2 progesterone receptor was significantly higher in WHO grade II tumors (72.7%) vs. WHO grades I (8.8%) or III (0%). On the other hand, the rate of grade 3 progesterone receptor was significantly higher in WHO grades I (85.3%) and III (100%) tumors than in WHO grade II (27.3%) (p = 0.01). The rate of grade 3 Ki-67 labeling index was significantly higher in WHO grade III tumors (100%) than in WHO grades I and II (zero for both, p < 0.001). This study showed that firstly, estrogen receptor is seldom expressed in patients with meningioma; however, its presence means a good prognosis. Secondly, Ki-67 labeling index is a marker of poor prognosis in these patients. Thirdly, although, progesterone receptors are frequently expressed in meningioma, their prognostic role varies greatly and needs to be determined in further studies.