CCL2 and cancer: Furthermore, hypothalamic expression of inflammatory genes <i>Ccl2</i> and <i>Il6</i> was tightly correlated with each other in all groups, while <i>Ccl2</i> was negatively correlated with <i>Hcrt</i> and <i>Pomc</i> in TB<sub>low</sub> mice, suggesting a role for CCL2 in regulating neuropeptide expression.<h4>Discussion</h4>The metabolic profile and hypothalamic gene expression can vary with differential initial tumor load, suggesting that the relationship between systemic energy balance and cancer progression is complex and not strictly linear.