Differentiation of melanoma from non-cancerous tissue in an animal model using elastic light single-scattering spectroscopy.

Cutaneous melanoma is the most serious form of skin cancer and is curable only if it is detected early. The most effective treatment for the melanoma is surgical excision of the lesion. Traditionally, wide margins of excision have been used for effective treatment, but are not always desirable due to increased risk of infection and esthetic reasons. Besides, safe surgical margins of the lesion are not always correlated well with the size of the lesions. We have previously developed a system using elastic light single-scattering spectroscopy to differentiate cancerous tissue from non-cancerous tissue and tested it in vitro. The goal of this study was, therefore, to determine the effectiveness of this system ex vivo by using a mouse model of melanoma. First, a melanoma cell line; B16F10 were injected subcutaneously at right mid flank region of C57BL6 mice (n=5) and allowed to develop for two weeks. Tumors were dissected and spectra were taken on tumor tissue and on normal looking skin tissue that was 10 mm distant from the incision. Since these tumors become markedly necrotic in the middle, spectra of necrotic area was also taken. Slopes of the spectra were positive taken on non-cancerous skin tissues that were later verified by histological examination. On the other hand, it gave negative slopes on melanomas. Increased sizes of the nuclei correlated with the negative slope while smaller nuclei found in non-cancerous tissue gave positive slope. Spectrum taken from necrotic area differed from both cancerous and non-cancerous tissue such that it gave a U-shaped spectrum. These results demonstrate that elastic light single-scattering spectroscopy system can differentiate cancerous tissue from non-cancerous and has potential to be used intraoperatively to determine the surgical margins.

Nitrotyrosine formation and apoptosis in rat models of ocular injury.

This study was performed to examine inducible nitric oxide synthase (NOS-2) expression, nitrotyrosine formation and apoptosis in rats with elevated intraocular pressure (IOP) and/or ocular inflammation. Ocular inflammation was induced via injection of intra-vitreal lipopolysaccharide (LPS) while IOP was elevated by episcleral vessel cauterization. Animals were randomized to one of the following conditions: elevated IOP, LPS, elevated IOP+LPS, and control. Immunohistochemical staining and western blot analysis of retinal lysates revealed NOS-2 and nitrotyrosine immunoreactivity in all disease groups. NOS-2 expression and protein nitration was significantly greater in rats with elevated IOP+LPS compared to elevated IOP, LPS, and control groups. Nitrite levels in the retina affirmed significantly increased levels of nitric oxide generation in LPS-treated rats with elevated IOP (346+/-23.8 microM) vs LPS-treated, elevated IOP and control groups (195.6+/-12.6, 130+/-2.5 and 76.6+/-15.6 microM, respectively). Retinal TUNEL staining showed apoptosis in all diseased groups. Percent of apoptotic cells was significantly greater in the elevated IOP+LPS group compared to LPS-treated or elevated IOP groups. Presented data illustrates that both elevated IOP and ocular inflammation augment NOS-2 expression, retinal protein nitration and apoptosis in rats.

Effect of hypercholesterolemia on inducible nitric oxide synthase expression in a rat model of elevated intraocular pressure.

PURPOSE: This study was performed to examine the effect of hypercholesterolemia on inducible nitric oxide synthase (NOS-2) expression and oxidative tissue injury in an experimental rat model of elevated IOP. METHODS: Wistar rats were maintained on either regular chow or a high-cholesterol diet for 24 weeks. Intraocular pressure (IOP) was elevated in hypercholesterolemic rats by unilaterally cauterizing three episcleral vessels. Rats were divided into four experimental groups as follows; hypercholesterolemia, hypercholesterolemia+elevated IOP, elevated IOP and control. NOS-2 distribution, lipid peroxidation and retinal nerve fiber layer (RNFL) thickness was evaluated in all experimental groups at the end of 24 weeks. RESULTS: Light microscopic evaluation of retinas in hypercholesterolemic rats revealed breaks and discontinuation in focal areas in the outer nuclear layer (ONL). NOS-2 positive staining was observed throughout the outer plexiform layer (OPL), inner plexiform layer (IPL) and ganglion cell layer (GCL) in rats with elevated IOP and/or hypercholesterolemia. Calculated values of RNFL thickness in hypercholesterolemic rats were significantly higher than those in the control and elevated IOP group. Vitreous malondialdehyde (MDA) levels detected in elevated IOP (3.51+/-0.31 nmol/mg protein) and hypercholesterolemia+elevated IOP (5.14+/-1.28 nmol/mg protein) groups were significantly higher than those detected in hypercholesterolemic (1.92+/-1.43 nmol/mg protein) and control (1.89+/-0.24 nmol/mg protein) groups. CONCLUSION: The presented data confirms hypercholesterolemia as a risk factor in the development of glaucomatous optic neuropathy (GON) and suggests that increased circulating cholesterol may exacerbate disease progression by inducing NOS-2 expression and elevating oxidant tissue injury.

Apoptotic and proliferative index after Alpha-1-adrenoceptor antagonist and/or finasteride treatment in benign prostatic hyperplasia.

INTRODUCTION: The induction of apoptosis has emerged as a potential target for optimization of the medical management of benign prostatic hyperplasia (BPH), recently. The influence of alpha1-adrenoceptor antagonist (alpha1-ARA), 5-alpha reductase inhibitor and their combination on prostatic cell apoptotic and proliferative indices of benign hyperplastic prostate gland were investigated. MATERIALS AND METHODS: A total of 49 male patients with BPH (mean age: 66.5 years) treated with alpha1-ARA and/or finasteride were retrospectively evaluated. Patients treated with alpha1-ARA (doxazosin n = 12 and terazosin n = 10), finasteride (n = 9) and combination of finasteride and alpha1-ARA (n = 9) were enrolled in the study. Primary antibodies were Ki-67 and proliferating cell nuclear antigen for the evaluation of proliferation in prostate stromal and epithelial cells. In situ apoptotic DNA fragmentation was evaluated using TUNEL assay. RESULTS: All treatment groups had no significant changes in the rate of prostate stromal and epithelial cell proliferation. Epithelial apoptotic index (AI) was not statistically significant for finasteride vs. alpha1- ARA, alpha1-ARA vs. finasteride + alpha1-ARA and finasteride + alpha1-ARA vs. finasteride groups. While alpha1-ARA was more effective than finasteride on stromal apoptosis, alpha1-ARA-induced stromal apoptosis was not significantly different from alpha1-ARA plus finasteirde treatment. CONCLUSION: Not only androgen variabilities but also alterations in sympathetic neurotransmission with age could have important implications for pathophysiological prostate growth. The combination of finasteride and alpha1-ARA is not superior to alpha1-ARA therapy with their similar epithelial and stromal apoptotic effects with unaffected cell proliferation.