Browsing by Subject "Chemoprevention"

Now showing 1 - 4 of 4
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    A COX-2 inhibitor, nimesulide, inhibits chemically-induced rat tongue carcinogenesis through suppression of cell proliferation activity and COX-2 and iNOS expression
    (Murcia : F. Hernández, 2003) Yoshida, K.; Tanaka, T.; Kohno, H.; Sakata, K.; Kawamori, T.; Mori, H.; Wakabayashi, K.
    The modifying effects of a cyclooxygenase (cox)-2 selective inhibitor nimesulide on tongue carcinogenesis were investigated in male F344 rats initiated with 4-nitroquinoline-1-oxide (4-NQO). The cell proliferation activity measured by proliferating cell nuclear antigen (PCNA)-positive index and apoptotic index, and the immunohistochemical expression of COX-2, and inducible nitric oxide synthase (iNOS) in the tongue mucosa or neoplasms were also examined for mechanistic analysis of modifying effects of nimesulide on tongue carcinogenesis. All animals except those treated with nimesulide alone and untreated rats were given 20 ppm 4-NQO in drinking water for 8 weeks to induce tongue neoplasms. Starting 1 week after the cessation of 4-NQO exposure, rats given 4-NQO were fed the experimental diets containing nimesulide (100 and 400 ppm) for 22 weeks. At week 32, the incidence of tongue squamous cell carcinoma was significantly reduced by feeding of the diet containing 400 ppm nimesulide. Feeding of nimesulide significantly decreased polyamine content and PCNA-labeling index in tongue carcinoma. Apoptotic index in tongue carcinoma was increased by feeding of nimesulide. In addition, nimesulide feeding reduced COX-2 and iNOS expression in the tongue dysplasia and neoplasms. These results suggest that 400 ppm nimesulide in diet, when given during the promotion phase, exerts chemopreventive ability against 4-NQO-induced tongue tumorigenesis through inhibition of cell proliferation activity in conjunction with modification of COX-2 and iNOS expression of the target lesions.
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    An update on the pathobiological relevance of nuclear receptors for cancers of the head and neck
    (Murcia : F. Hernández, 2010) Stauber, Roland H.; Wünsch, Desiree; Knauer, Shirley K.; Fetz, Verena
    Cancers of the head and neck are among the most common neoplasms worldwide, characterized by local tumor aggressiveness, high rate of early recurrence, development of metastasis and second primary tumors. Although disease management of head and neck cancer has improved significantly, overall survival-rates remained largely unchanged over the last decades. Thus, in addition to modern chemo-radiation treatment strategies combined with sophisticated surgery, there is still a need for molecular markers and key regulatory factors exploitable for chemoprevention and targeted therapies. A critical event in carcinogenesis is the uncontrolled modulation of genetic programs, mediated by deregulated signaling cascades, together with downstream transcriptional modulators. Hence, nuclear receptors, belonging to a superfamily of transcription factors implicated in a broad spectrum of physiological and pathophysiological processes, have also been associated with HNC. Enhanced expression of several nuclear receptors has been shown in head and neck cancer cells, and strategies targeting these molecules have been developed and tested in the clinics. In particular, the effects of retinoids targeting nuclear receptors of the thyroid hormone receptor-like receptor subfamily have been vigorously examined in large clinical chemoprevention trials. This review seeks to provide a general overview of nuclear receptors’ molecular functions and summarizes their prognostic/therapeutic relevance, as well as the (pre)clinical studies targeting nuclear receptors in HNC.
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    Anticancer properties of carotenoids in prostate cancer. A review
    (F. Hernández y Juan F. Madrid. Universidad de Murcia: Departamento de Biología Celular e Histología, 2015) da Costa Pereira Soares, Nathalia; Junger Teodoro, Anderson; Falagan Lotsch, Priscila; Mauro Granjeiro, José; Borojevic, Radovan
    Prostate cancer is the most common noncutaneous cancer of men in the world. Several epidemiological studies have linked increased carotenoids consumption with decreased prostate cancer risk. These findings are supported by in vitro and in vivo experiments showing that carotenoids not only enhance the antioxidant response of prostate cells, but that they are able to inhibit proliferation, induce apoptosis and decrease the metastatic capacity of prostate cancer cells. However, clear clinical evidence supporting the use of carotenoids in prevention or treatment of prostate cancer is not available, due to the limited number of published randomized clinical trials, and the varying protocols used in the existing studies. The scope of the present review is to discuss the potential impact of carotenoids on prostate cancer by giving an overview of the molecular mechanisms and in vitro / in vivo effects.
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    Histopathological effect of pterostilbene as chemoprevention in N-nitroso-tri-chloroethylurea (NTCU)-induced lung squamous cell carcinoma (SCC) mouse model
    (Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2020) Surien, Omchit; Ghazali, Ahmad Rohi; Masre, Siti Fathiah
    ackground. Lung cancer is the leading cause of cancer-related deaths, and squamous cell carcinoma (SCC) is one of the most common types of lung cancer. Chemoprevention of lung cancer has gained increasing popularity as an alternative to treatment in reducing the burden of lung cancer. Pterostilbene (PS) may be developed as a chemopreventive agent due to its pharmacological activities, such as anti-proliferative, anti-inflammatory and antioxidant properties. This study aimed to investigate the effect of PS on the development of lung SCC in the mouse model. Methods. A total of 24 seven-week-old female Balb/C mice were randomly categorised into four groups, including two control groups comprising the N-nitroso-trischloroethylurea (NTCU)-induced lung SCC and vehicle control (VC) groups and two treatment groups comprising the 10 mg/kg PS (PS10) and 50 mg/kg PS (PS50) groups. All lung organs were harvested at week 26 for histopathological analysis. Results. All PS treatment groups showed chemopreventive activity by inhibiting the progression of lung SCC formation with PS10, resulting in mild hyperplasia, and PS50 was completely reversed in the normal bronchial epithelium layer compared with the VC group. PS treatment also reduced the expression of cytokeratin 5/6 in the bronchial epithelium layer. Both PS10 and PS50 significantly reduced the epithelium thickness compared to the NTCU group (p<0.05). PS is a potential chemopreventive agent against lung SCC growth by suppressing the progression of pre-malignant lesions and reducing the thickness of the bronchial epithelium. Conclusions. The underlying molecular mechanisms of PS in lung SCC should be further studied