Human cancers have been found to include transformed stem cells that may drive cancer progression to metastasis. Here, we report that metastatic colon cancer contains clonally derived tumor cells with all of the critical properties expected of stem cells, including self-renewal and the ability to differentiate into mature colon cells. Additionally, when injected into mice, these cells initiated tumors that closely resemble human cancer. Karyotype analyses of parental and clonally derived tumor cells expressed many consistent (clonal) along with unique chromosomal aberrations, suggesting the presence of chromosomal instability in the cancer stem cells. Thus, this new model for cancer origin and metastatic progression includes features of both the hierarchical model for cancerous stem cells and the stochastic model, driven by the observation of chromosomal instability. [Cancer Res 2008;68(17):6932-41]

Dendritic cells (DCs) are nature's best antigen-presenting cells. They possess attributes that allow them to effectively fulfill the requirements for priming/activating T cells and mediating tumor-specific immune responses. In this review, emphasis is placed on those aspects of DC biology that best illustrate their usefulness in immunotherapy of cancer. Culture, maturation, and polarization conditions for human DC are discussed, as are strategies for antigen-loading of DCs and for their delivery to patients with cancer. A concise recommendation for monitoring of DC-based vaccination trails is provided.

Paclitaxel induces apoptosis in lung cancer cell lines, as assessed by a consistent increase in caspase-3 activity, DNA laddering, and characteristic morphologic changes. Paclitaxel-induced apoptosis in human lung cancer cells is associated with caspase-3 activation but is not Fas dependent.