Models of carcinogenesis

The simplest experimental model of carcinogenesis is the three-stage model (Pitot and Dragan, 1994) consisting of  

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JAVED s, MEHROTRA N K and SHUKLA Y (1998) Chemopreventive effects of black tea polyphenols in mouse skin model of carcinogenesis , Biomed Environ Sci, 11 (4), 307-13. 

In preclinical models of carcinogenesis, which include colorectal, breast, and prostate cancer, a remarkable efficacy of some phytochemicals has been found. Some of these are epigallocatechin from tea quercetin and genistein from onion and soy,... 

M. Pater, and A. Pater. Malignant trans formation of human ectocervical cells immortalized by HPV 18 in vitro model of carcinogenesis by cigarette smoke. Carcinogenesis 1996 17(3) 577-83. 

Trosko JE, Chang C-C, Madhukar BV, et al. 1995. Intercellular communication A paradigm for the interpretation of the initiation/promotion/progression model of carcinogenesis. In Chemical induction of cancer Modulation and combustion effects. 205-225. 

Additional tests may either be short or medium-term in vivo rodent test systems, usually using the mouse. These models of carcinogenesis may use transgenic or neonatal rodents. The guideline also includes models... 

Figure 2.13 A simple 2-stage model of carcinogenesis. Within the framework, the possibility of two initiated populations for adequately describing the kinetics of liver GST-P foci growth was evaluated. The cell division and death rates of normal hepatocytes are denoted by a and p, respectively. The probability of mutation per cell division to A or B initiated cells per day are donoted by pa and pb. The division and death rates of A, B cells are denoted by < a> Pa- < b> Pb. respectively.

Taningher M, Perrotta A, Malacame D, et al. 1995. Lack of significant promoting activity by benzene in the rat liver model of carcinogenesis. J Toxicol Environ Health 45 481-488. 

Peto J, Seidman H, Selikoff IJ. 1982. Mesothelioma mortality in asbestos workers Implications for models of carcinogenesis and risk assessment. Br J Cancer 45 124-135. 

Resveratrol has been reported to have chemo-preventive activity in a mouse model of carcinogenesis, but there is a concentration-dependent effect, and at the concentrations used in vitro the effect is predominantly antiproliferative. It has also been reported to have mitochondrial-dependent apoptotic activity against a variety of cell lines. Resveratrol has been reported to inhibit the constitutive COX-1, but it is not clear whether it inhibits the inducible COX-2. These cyclo-oxygenases stimulate tumor growth by acting on cell proliferation, angiogenesis, and immuno-suppression.f °° ... 

Portier CJ, Kopp-Schneider A, Sherman CD. Calculating tumor incidence rates in stochastic models of carcinogenesis. Math Biosci 1996 135 129 16. 

Herein, we examine a variety of models of carcinogenesis. Our review is not intended to be exhaustive. Instead, we focus on models that have received considerable attention and in doing so have contributed much to our understanding. Likewise, we also highlight fish model systems that offer the potential to provide unique insights upon further study. 

Laboratory fish models of carcinogenesis complement and attempt to provide an explanation for observations made in the field. Historically, the fish species selected for such studies differ in the lab, small domestic freshwater fish are opted for in the held, estuarine species living in close association with contaminated sediments are selected. Extrapolating across species has its limits, though it has nevertheless been possible to determine much of the universal mechanisms relating to the carcinogenesis process in fish species. 

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