Table 1.
Effects of stress and stress-associated hormones on cancer
| Experimental manipulation | Animal | Biological effect | Tumour type | Effect on tumour growth | References |
|---|---|---|---|---|---|
| Confrontation | Rats | NA | Breast | Increased metastasis of tumour cells to the lung | 25 |
| Restraint stress | Rats | Decreased numbers of T cells | Mammary | Increased growth during stress | 144 |
| Forced swim | Rats | Decreased natural-killer-cell activity | Leukaemia | Increased mortality | 22 |
| Abdominal surgery | Rats | Decreased natural-killer-cell activity | Mammary | Increased metastasis of tumour cells to the lung | 22 |
| High versus low dopaminergic reactivity | Rats | Decreased angiogenesis with high dopaminergic reactivity | Mammary | Fewer lung metastasis with increased dopaminergic reactivity | 145 |
| Dopamine administration | Mice | Decreased angiogenesis; decreased VEGF– VEGFR2 binding and phosphorylation | Ovarian | Decreased ascites formation | 56 |
| Dopamine administration | Mice | Decreased angiogenesis | Gastric | Decreased growth | 55 |
| Social isolation | Mice | Decreased macrophage activity | Ehrlich | Increased growth | 146 |
| Immobilization stress | Mice | Increased angiogenesis | Ovarian | Increased growth | 30 |
| Restraint stress | Mice | Decreased IL-12, IFNγ, CCL27 (also known as CTACK) and numbers of infiltrating T cells; increased numbers of suppressor cells | Skin and squamous cell carcinoma | Increased incidence, number, size and density | 110 |
CTACK, cutaneous T-cell attracting chemokine; IL-12, interleukin-12; IFNγ, interferon-γ; NA, not available; VEGF, vascular endothelial growth factor; VEGFR2, VEGF receptor 2.