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Background:Melanoma is one of the most aggressive cancers, and it is estimated that 76,250 men and women will be diagnosed with melanoma of the skin in the USA in 2012. Over the last few decades many drugs have been developed but only in 2011 have new drugs demonstrated an impact on survival in metastatic melanoma.Methods:A systematic search of literature was conducted, and studies providing data on the effectiveness of current and/or future drugs used in the treatment of metastatic melanoma were selected for review. This review discusses the advantages and limitations of these agents, evaluating past, current and future clinical trials designed to overcome such limitations.Results:To date, there are four drugs approved by the Food and Drug Administration for melanoma (dacarbazine, interleukin-2, ipilimumab and vemurafenib). Despite efforts to develop new drugs, few of them have demonstrated any clinical benefits. Approved in 1975, dacarbazine remains the gold standard in chemotherapy, although ipilimumab and vemurafenib have raised many hopes in the last few years. Combining dacarbazine or other chemotherapy agents with new pharmacological agents may be a new way to achieve better clinical responses in patients with metastatic melanoma.Discussion:Advances in the molecular knowledge of melanoma have led to major improvements in the treatment of patients with metastatic melanoma, providing new targets and insights. However, heterogeneity amongst study populations, different approaches to treatment and the different melanoma types and localisations included in the trials makes their comparison difficult. New studies focusing on drugs developed in recent decades are warranted.

Sepsis is a life-threatening organ dysfunction condition caused by a dysregulated host response to an infection. Here we report that the circulating levels of growth and differentiation factor-15 (GDF15) are strongly increased in septic shock patients and correlate with mortality. In mice, we find that peptidoglycan is a potent ligand that signals through the TLR2-Myd88 axis for the secretion of GDF15, and thatGdf15-deficient mice are protected against abdominal sepsis due to increased chemokine CXC ligand 5 (CXCL5)-mediated recruitment of neutrophils into the peritoneum, leading to better local bacterial control. Our results identify GDF15 as a potential target to improve sepsis treatment. Its inhibition should increase neutrophil recruitment to the site of infection and consequently lead to better pathogen control and clearance.

Summary Several classes of antibiotics have long been known to have beneficial effects that cannot be explained strictly on the basis of their capacity to control the infectious agent. Here, we report that tetracycline antibiotics, which target the mitoribosome, protected against sepsis without affecting the pathogen load. Mechanistically, we found that mitochondrial inhibition of protein synthesis perturbed the electron transport chain (ETC) decreasing tissue damage in the lung and increasing fatty acid oxidation and glucocorticoid sensitivity in the liver. Using a liver-specific partial and acute deletion of Crif1 , a critical mitoribosomal component for protein synthesis, we found that mice were protected against sepsis, an observation that was phenocopied by the transient inhibition of complex I of the ETC by phenformin. Together, we demonstrate that mitoribosome-targeting antibiotics are beneficial beyond their antibacterial activity and that mitochondrial protein synthesis inhibition leading to ETC perturbation is a mechanism for the induction of disease tolerance.

Sepsis is a life-threatening organ dysfunction condition caused by a dysregulated host response to an infection. Here we report that the circulating levels of growthdifferentiation factor-15 (GDF15) are strongly increased in septic shock patients and correlate with mortality. In mice, we find that peptidoglycan is a potent ligand that signals through the TLR2-Myd88 axis for the secretion of GDF15 and that Gdf15deficient animals are protected against abdominal sepsis due to increased chemokine CXC ligand 5 (CXCL5)-mediated recruitment of neutrophils into the peritoneum leading to better local bacterial control. Our results identify GDF15 as a potential target to improve sepsis treatment. Its inhibition should increase neutrophil recruitment to the site of infection and consequently lead to better pathogen control and clearance.Anorexia and weight loss are key features of the wasting syndrome that often accompanies late-stages of cancer and where GDF15 is known to play a critical role (12). These signs, including long-lasting loss of muscle mass, are also observed in sepsis (13). The common pathological features of both conditions led us to investigate whether GDF15 is increased in sepsis and if it plays a role in its pathophysiology.

Synergy of resistance and disease tolerance mechanisms is necessary for an effectiveimmune response leading to survival and return to homeostasis when an organism is challenged by infection. Antibiotics are used for their resistance enhancement capabilities by decreasing pathogen load, but several classes have long been known to have beneficial effects that cannot be explained strictly on the basis of their capacity to control the infectious agent. Here we report that tetracycline antibiotics, a class of ribosome-targeting drugs, robustly protects against sepsis by inducing disease tolerance, independently from their direct antibiotic properties. Mechanistically, we find that mitochondrial inhibition of protein synthesis perturbs the electron transfer chain and leads to improved damage repair in the lung and fatty acid oxidation and glucocorticoid sensitivity in the liver. Using a partial and acute deletion of CRIF1 in the liver, a critical mitoribosomal component for protein synthesis, we find that mice are protected against bacterial sepsis, an observation which is phenocopied by the transient inhibition of complex I of ETC by phenformin. Together, we demonstrate that ribosome-targeting antibiotics are beneficial beyond their antibacterial activity and that mitochondrial protein synthesis inhibition leading to ETC perturbation is a novel mechanism for the induction of disease tolerance.

The cytokine TNF drives inflammatory diseases, e.g., Crohn's disease. In a mouse model of TNF ‐induced systemic inflammatory response syndrome ( SIRS ), severe impact on intestinal epithelial cells ( IEC s) is observed. Zinc confers complete protection in this model. We found that zinc no longer protects in animals which lack glucocorticoids ( GC s), or express mutant versions of their receptor GR in IEC s, nor in mice which lack gut microbiota. RNA ‐seq studies in IEC s showed that zinc caused reduction in expression of constitutive ( STAT 1‐induced) interferon‐stimulated response ( ISRE ) genes and interferon regulatory factor ( IRF ) genes. Since some of these genes are involved in TNF ‐induced cell death in intestinal crypt Paneth cells, and since zinc has direct effects on the composition of the gut microbiota (such as several Staphylococcus species) and on TNF ‐induced Paneth cell death, we postulate a new zinc‐related anti‐inflammatory mechanism. Zinc modulates the gut microbiota, causing less induction of ISRE / IRF genes in crypt cells, less TNF ‐induced necroptosis in Paneth cells, and less fatal evasion of gut bacteria into the system.