Tea is the second only to water as the most consumed beverage in the world. Both green and black teas have been studied for their health benefits for a variety of diseases, particularly cancer. Lung cancer is the predominant cause of cancer mortality in developed countries. Smokers' risk of lung cancer is 20 times that of persons who have never smoked. Epidemiological studies on the cancer-preventive effects of tea produce inconsistent results, which could in part be attributed to the lack of a universal standard for tea preparations. However, most animal studies indicate that tea has strong chemopreventive effects against lung tumorigenesis. The reported mechanisms for chemopreventive activity of green tea are antioxidation, induction of phase II enzymes, inhibition of TNFalpha expression and release, inhibition of cell proliferation, and induction of apoptosis. Cell cycle arrest and apoptosis induced by green tea are probably the two most significant factors. Future studies are needed to determine how green tea affects the genes associated with cell cycle regulation and apoptosis during the mouse lung carcinogenesis process.

Ki-67 expression in ductal cells obtained by random periareolar fine needle aspiration (RPFNA) is currently being used as a response biomarker in phase II breast cancer chemoprevention trials; however, Ki-67 in RPFNA has not been well studied as a risk predictor for cancer, which would support its use as a response indicator. We examined the expression of Ki-67 in RPFNA specimens with hyperplasia F atypia obtained from 147 women at high risk for development of breast cancer. Median Ki-67 was 1.4% (range 0-24%). Ki-67 was higher in specimens from women <50 versus those z50 (median 2% versus 0.6%; P = 0.006) and from premenopausal women versus postmenopausal women (P = 0.037); however, hormone replacement therapy (predominately low-dose estrogen without progestins) had no effect. By univariate analysis, Ki-67 was positively correlated with ductal cell number (P = 0.001) and hyperplasia with atypia (P = 0.007). By multivariable analysis, the proportion of ductal cells expressing Ki-67 was again predicted by cell number, which, in turn, was predicted by cytologic atypia. The association of Ki-67 expression with cytologic atypia, a known risk factor for development of breast cancer, provides preliminary justification for its use as a response biomarker in phase II chemoprevention trials. (Cancer Epidemiol Biomarkers Prev 2005;14(4):786 -9)

Drug discovery and development efforts critically rely on cell-based assays for high-throughput screening. These assay systems mostly utilize immortalized cell lines, such as human embryonic kidney cells, and can provide information on cytotoxicity and cell viability, permeability and uptake of compounds as well as receptor pharmacology. While this approach has proven extremely useful for single-target pharmacology, there is an urgent need for neuropharmacological studies to screen novel drug candidates in a cellular environment resembles neurons in vivo more closely, in order to gain insight into the involvement of multiple signaling pathways. Primary cultured neuronal cells, such as cortical neurons, have long been used for basic research and low-throughput screening and assay development, and may thus be suitable candidates for the development of neuropharmacological high-throughput screening approaches. We here developed and optimized protocols for the use of primary cortical neuronal cells in high-throughput assays for neuropharmacology and neuroprotection, including calcium mobilization, cytotoxicity and viability as well as ion channel pharmacology. Our data show low inter-experimental variability and similar reproducibility as conventional cell line assays. We conclude that primary neuronal cultures provide a viable alternative to cell lines in high-throughput assay systems by providing a cellular environment more closely resembling physiological conditions in the central nervous system.

Ductal lavage (DL) and random periareolar fine needle aspiration (RPFNA) are both being used to harvest epithelial cells for risk assessment as well as response evaluation in chemoprevention trials. The magnitude of increase in relative risk has been defined in a prospective study for RPFNA but not for DL atypia. We attempted both procedures in 26 women at high risk for development of breast cancer. Median age was 43 (range 32-57); 15 women were premenopausal, with 6 of the postmenopausal women on HRT. Collection of nipple aspirate fluid (NAF) was attempted and, if successful, was followed by DL; RPFNA was then performed on all women. Both procedures were attempted the same day (follicular phase of menstrual cycle if premenopausal) in 24 subjects and within three months for two subjects. Twenty-three subjects produced NAF, 17 of the 23 (74%) had a successful duct cannulation as part of the DL procedure, with 16 yielding sufficient (10) ductal cells for morphologic assessment. Twenty-five of 26 (96%) subjects had a successful RPFNA procedure with adequate cellularity for morphology. There was concordance between DL and RPFNA specimens for traditional cytologic category assessment in 10/16 (63%), Masood index score in 13/16 (82%), and Consensus Panel assessment in 12/16 (75%) of specimens. We conclude that same day DL and RPFNA is feasible, with 62% and 96% of high-risk women having a successful procedure with evaluable cytomorphology. RPFNA was more likely to yield an evaluable specimen, but if a cellular DL specimen was obtained, morphology was generally similar.

Immunostaining of estrogen receptor alpha (ER) in samples of benign breast tissue obtained by random periareolar fine-needle aspiration (RPFNA) is a practical tool for breast cancer chemoprevention trials. The authors report an optimized method of ER immunostaining for use with thin-layer preparations of modified Cytolyt-fixed benign breast tissue acquired by RPFNA. Samples of benign breast tissue and MCF-7 controls processed as thin-layer preparations were tested for the effects of antibody titer, antigen retrieval temperature (90 degrees or 115 degrees C), buffer (20% nuclear decloaker, pH 9.3; 10 mM citrate buffer, pH 6), and blocking solution (0.01% glucose oxidase or 0.3% H2O2) on ER immunostaining. The prevalence of positively stained breast epithelial cells, mean intensity of ER staining, and composite immunostaining score were evaluated for effect of immunostaining protocol. RPFNA samples and MCF-7 cells processed using nuclear decloaker and low-temperature antigen retrieval had more ER-positive cells (P<0.0001) and increased mean staining intensity and weighted staining indices (P<0.05) compared with samples prepared with citrate buffer and high-temperature antigen retrieval. Glucose oxidase increased ER-positive cells in comparison to hydrogen peroxide (P<0.04) when combined with low-temperature antigen retrieval and the use of nuclear decloaker. Staining was negative for all non-immune controls regardless of protocol. The combination of low-temperature antigen retrieval, diluted commercial nuclear decloaker solution, and a glucose oxidase blocking step yielded optimal ER immunostaining for thin-layer preparations of benign breast tissue harvested by RPFNA.