TLR4 and neoplasm: As an innate immune response, activation of TLR4 on myocytes and immune cells can increase their synthesis and secretion of inflammatory cytokines31 such as TNFα, IL-6 and IL-1β that promote muscle wasting, it is possible that tumor-released extracellular Hsp70 and Hsp90 cause the increase of circulating cytokines in tumor milieu.