Screening of new cell cycle suppressive compounds from marine-derived microorganisms in Chinese hamster ovary cells.

Monoclonal antibodies (mAbs) are active pharmaceutical ingredients in antibody drugs, produced mainly using recombinant Chinese hamster ovary (CHO) cells. The regulation of recombinant CHO cell proliferation can improve the productivity of heterologous proteins. Chemical compound approaches for cell cycle regulation have the advantages of simplicity and ease of use in industrial processes. However, CHO cells have genetic and phenotypic diversity, and the effects of such compounds might depend on cell line and culture conditions. Increasing the variety of cell cycle inhibitors is a promising strategy to overcome the dependency. Marine microorganisms are a vast and largely undeveloped source of secondary metabolites with physiological activity. In this study, we focused on secondary metabolites of marine microorganisms and evaluated their effectiveness as cell cycle inhibitory compounds. Of 720 extracts from microorganisms (400 actinomycetes and 320 filamentous fungi) collected from the Okinawan Sea, we identified nine extracts that decreased the specific growth rate and increased the specific production rate without reducing cell viability. After fractionating the extracts, the components of active fractions were estimated using time-of-flight mass spectrometry analysis. Then, four compounds, including staurosporine and undecylprodigiosin were deduced to be active compounds. These compounds have been reported to exert a cell cycle inhibitory effect on mammalian cells. These compounds might serve as additives to improve mAb production in CHO cells. This study indicates that secondary metabolites of marine microorganisms are a useful source for new cell cycle inhibitory compounds that can increase mAb production in CHO cells.

[Evaluation of liaison-clinical pathway for patients with breast cancer undergoing adjuvant therapy after curative operation--data from questionnaire survey of 56 clinics and 105 patients].

To evaluate the liaison-clinical pathway for patients with breast cancer introduced since May 2008, the data from a questionnaires survey of 56 clinics and 105 patients were reviewed. Half of the clinics specialized in internal medicine. 93% of physicians recognized the utility of the pathway while 24% made the most of the pathway. About 40% of the clinics wished to enlarge both the patient number and treatment materials. Half of the patients were employed. 55% of patients valued the pathway as helpful. And 29% of patients used the patient booklet at all times. 8% of patients replied they had complaints went to clinics. There has been no serious problem in using the pathway. Countermeasures to electronic health records in clinics, and responses to requests from each patient will be needed.