Paclitaxel damage

The answer is c. (Hardman7 pp 1269—1271.) Cisplatin causes acoustic nerve damage. Paclitaxel causes peripheral neuritis. Dose-... 

Paclitaxel (Taxol, Bristol-Myers Squibb) is a chemotherapy drug for ovarian cancer, breast cancer, and certain lung cancers. It was discovered by the US National Cancer Institute in the 1960s. Originally, it was extracted from the bark of the North American yew tree (Taxus brevifo-lia). Clinical tests had necessitated the harvesting of the bark, and this method damaged the trees irreversibly. 

In most studies where a supraadditive interaction was seen, cells were incubated with the drug prior to irradiation (38). In general the use of moderate concentrations (5-100 nmol/L) of paclitaxel in the culture medium for over 24 h lead to maximum sensitization. Most studies used actively proliferating cells in order to conduct their experiments and most investigators reached the conclusion that maximal radiosensitization occurred when cells were arrested in G2 and M, as this part of the cell cycle is the most sensitive to radiation damage. This assumption does, however, presuppose that the majority of the G2/M arrested cells will not die unless they are exposed to ionizing XRT. Plateau phase, i.e., nonproliferating, cells were found to be sensitized to radiation... 

Other suggested mechanisms for the increased radiosensitization seen with both paclitaxel and docetaxel include an increased alpha component of DNA damage and the fact that docetaxel is toxic for S-phase cells that are maximally radiation resistant (41,42). 

Most anticancer drugs damage hair follicles and produce partial or complete alopecia. Patients should be warned of this reaction, especially if paclitaxel, cyclophosphamide, doxorubicin, vincristine, methotrexate, or dactinomycin is used. Hair usually regrows normally after completion of chemotherapy. 

Figure 5.1 Examples of terpenoids that are of commercial importance or whose functional role in plants has recently been investigated. Isoprene may stabilize membranes at high temperatures. Camphor, artemisinin and paclitaxel (taxol) are valuable pharmaceuticals. The other three compounds appear to be involved in plant defence pulegone is toxic to herbivores polygodial is a herbivore feeding deterrent and (3 )-4,8-dimethyl-1,3,7-nonatriene, a Cn homoterpene, functions to attract herbivore enemies to herbivore-damaged plants.

Bone marrow suppression is a dose-limiting adverse effect often encountered with paclitaxel. Neutropenia occurs most commonly 8-10 days after treatment, and recovery usually occurs on days 15-21. Paclitaxel is relatively platelet-sparing, and thrombocytopenia and anemia are rare (26). There is no evidence that neutropenia is cumulative, suggesting that paclitaxel may not irreversibly damage hemopoietic stem cells (1). 

Cardiovascular Heart failure (New York Heart Association classes II-IV) has been observed in patients receiving trastuzumab, alone or in combination with paclitaxel or docetaxel, particularly after chemotherapy containing an anthracycline (doxorubicin or epirubicin) [303, 304, 305, 306. It can be moderate or severe and can be fatal. The results of many randomized trials have shown that the degree of cardiotoxicity is generally acceptable the incidence of cardiac damage caused by trastuzumab was 0.4-4.1% [307 ]. Older age, lower left ventricular ejection fraction, and antihypertensive medications are associated with an increased risk of cardiac dysfunction in patients receiving trastuzumab [308 "]. The cardiac dysfunction associated with trastuzumab is usually reversible on withdrawal and standard medical therapy [309 ]. In one case, trastuzumab-associated cardiomyopathy presented with complete left bundle-branch block mimicking acute coronary syndrome [310" ]. 

Mitotic inhibtors paclitaxel, docetaxel, ixabepilone, vinblastine Side effect cause peripheral nerve damage... 

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