Carcinogenicity, mechanisms

Yan, L.S. 1985. Study of the carcinogenic mechanism for polycyclic aromatic hydrocarbons — extended bay region theory and its quantitative model. Carcinogenesis 6 1-6. 

Looked at another way, the four major carcinogenic mechanisms are DNA damage, cell toxicity, cell proliferation and oncogene activation. Any effective program to identify those drags which have the potential to cause or increase the incidence of neoplasia in humans must effectively screen for these mechanisms (Kitchin, 1999). 

Lehman-McKeeman, L.D. Gamsky, E.A. (2000) Choline supplementation inhibits diethanolamine-induced morphological transformation in Syrian hamster embiyo cells evidence for a carcinogenic mechanism. Toxicol. Sci., 55, 303-310 Levin, J.O., Andersson, K. Hallgren, C. (1994) Exposure to low molecular polyamines during road paving. Ann. occup. Hyg., 38, 257-264 Lide, D.R. Milne, GW. A. (1996) Properties of Organic Compounds, Version 5.0 [CD-ROM], Boca Raton, FL, CRC Press... 

TABLE 27.2 Carcinogenic mechanisms for the neoplasms relevant to IMBPs... 

Williams, G.M. latropoulos, M.J. Weisburger, J.H. Chemical carcinogen mechanisms of action and implications for testing methodology. Exp. Toxic. Pathol. 1996, 48, 101-111. 

Various mathematical models have been developed to explore the implications for dose-response relations of what is known about carcinogenicity mechanisms. Under some sets of assumptions consistent with these mechanisms, the risk of neoplastic transformation at low doses is directly proportional to the target site dose. This is the so-called straight-line, or linear, model of dose-response a picture of it is presented in the next chapter. 

Scheme 8.2 Summary of potential carcinogenic mechanisms for estrogens using equilenin as an example. mER, membrane-associated estrogen receptor ERE, estrogen...

Another problem concerns the identiflability of carcinogenic mechanism using tumor incidence data. Using a simpler model than that shown in Figure 3, Fortier (1987) examined the ability of tumor incidence data to accurately differentiate between a low-dose linear chemically induced increase in the rate of mutations from normal cells to initiated cells and a low-dose nonlinear chemically induced increase in the birth rate of initiated cells. It was shown that the probability of incorrectly classifying one mechanism as the other was quite high, exceeding 50% in some cases. 

Sagtii M, Lim BH, Ichinose T (2000) Lung carcinogenesis by diesel exhaust particles and the carcinogenic mechanism via active oxygen. Inhalation Toxicol 12 215-223 Salma I, Balashazy I, Winkler-Heif R, Hofmann W, Zaray G (2002) Effect of particle mass size distribution on the deposition of aerosols in the human respiratray system. Aerosol Sd 33 119-132... 

In the case of melamine, such considerations on carcinogenic mechanisms are appropriate. The material has been associated with an increased incidence of bladder carcinomas in male rats. 

Screening of non-alternants (NAH s) is much less extensive than for alternants tested parents are listed in Table 4.6. Knowledge of the carcinogenesis of NAH s could be valuable since, unlike molecules containing heteroatoms, NAH s are likely to have a similar carcinogenic mechanism to that of AH s consequently, only physico-chemical correlations which can readily include NAH s are accept-... 

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