Circumvention of Biologic Diversity of Cancer Metastasis
The major challenge facing the oncologist is how to treat cancer that has disseminated to and is growing in multiple organs throughout the body. Despite major advances in general patient care, surgical techniques, and adjuvant therapies, most deaths from cancer are caused by the growth of metastases that are resistant to chemotherapy or radiotherapy. A major factor which prevents treatment of metastases is the fact that cancer cells populating both primary and secondary neoplasms are biologically heterogeneous (1, 2). By the time of diagnosis, and certainly in clinically advanced lesions, malignant neoplasms contain multiple cell populations exhibiting a wide range of biological characteristics such as cell surface structures, growth rate, sensitivity to various cytotoxic drugs, and the ability to further invade and metastasize. The implication of the heterogeneous responses of tumor cells to conventional anticancer drugs is that the successful therapy of disseminated metastases must circumvent the problems of biologic heterogeneity and be a treatment modality to which resistance is unlikely to develop.
KeywordsAlveolar Macrophage Spontaneous Metastasis Muramyl Dipeptide Human Blood Monocyte Conventional Anticancer Drug
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