Table 1.
In model systems, therapeutics and environmental conditions can differentially affect primary tumors and metastases.
| Histology | Findings | Reference |
|---|---|---|
| Breast | Systemic administration of a TGF-βRI-I inhibitor reduced the number of lung metastases and the incidence and burden of bone metastases with no effect on the orthotopic primary tumor | Bandyopadhyay et al. (2006)95 |
| Integrin-based peptidomimetics reduced lung metastasis by 44–68%, with no effect on primary tumor growth and only a minor difference in the number of circulating tumor cells | Shannon et al. (2004)51 | |
| The topoisomerase II inhibitor salvicine reduced lung metastasis by 33–68%, with no diminution of primary tumor growth, via a RhoC pathway | Lang et al. (2005)96 | |
| Osteosarcoma | Parthenolide, a NF-κB directed agent, inhibited lung metastasis fourfold in a prevention model with no significant effect on the growth of primary tumors. A similar trend was reported for mutant IκBα expression | Kishida et al. (2007)50 |
| Prostate | Norepinephrine increased, and propranolol decreased the lumbar lymph-node metastases of PC-3 cancer cells; growth of the primary tumor was not affected | Palm et al. (2006)97 |
| Prostate and melanoma | PC3M prostate and B16 melanoma cells were treated ex vivo with C90, a Grb-2 inhibitor, and injected. The compound inhibited lung metastasis by 50%, with no significant effect on primary tumor size | Giubellino et al. (200798 |
| Cervical | Acute hypoxia significantly decreased primary tumor size but increased the number of positive lymph nodes and the size of the lesions | Cairns and Hill (2004)99 |
| Pancreatic | Cyclopamine reduced the incidence of distant metastases to the spleen, liver, lymph nodes and peritoneum, with no significant effect on primary tumor volume | Feldmann et al. (2007)9 |
| Lung | RPI-1, a c-Met inhibitor, did not inhibit subcutaneous tumors produced by H460 lung cancer cells at 100 mg/kg, but reduced metastases by 57% | Cassinelli et al. (2006)100 |