Protracted Inhibition of Vascular Endothelial Growth Factor Signaling Improves Survival in Metastatic Colorectal Cancer: A Systematic Review.

Clinical data suggest that beyond-progression, the blockade of angiogenesis is associated with improved survivals in colorectal cancer. We conducted a systematic review to investigate the therapeutic effects of antiangiogenic drugs administered as later lines of treatment in patients already progressed to a previous anti-VEGF based treatment. An extensive literature search was conducted. Hazard ratios (HR) for progression (PFS) and death (OS) were extracted. An inverse-variance meta-analysis model was implemented. 6 randomized controlled trials were retrieved, including 3407 patients, treated with different antiangiogenic drugs. All of them had progressed during or after a previous line of treatment with bevacizumab. Overall, both PFS (HR=0.63, P <0.001) and OS (HR=0.81, P < 0.001) were significantly increased with the use of antiangiogenic drug. No heterogeneity was observed despite different drugs. Protracted inhibition of the VEGF pathway is associated with a significant improvement of both PFS and OS, independently from the antiangiogenic agent used.

Progression-free Survival as a Surrogate End-point in Advanced Colorectal Cancer Treated with Antiangiogenic Therapies.

BACKGROUND: It is not clear if progression-free survival (PFS) is a good surrogate end-point for overall survival (OS) for metastatic colorectal cancer if antiangiogenic therapies are used. MATERIALS AND METHODS: We investigated randomized controlled trials testing antiangiogenic agents against chemotherapy. Log hazard ratios (HR) for PFS and OS were used to construct linear regression models. The surrogate threshold effect (STE) was calculated. RESULTS: Thirteen studies and 24 comparison arms were available, including 7,179 patients. This model returned a significant correlation between PFS and OS (R(2)=0.68, p<0.001) with an STE of 0.83. Analysis restricted to first-line gave similar results (R(2)=0.68, p<0.001, STE=0.75). CONCLUSION: There is a significant correlation between the effect of treatment on PFS and OS. PFS remains a good surrogate end-point for OS even if anti-angiogenic agents are used.

Appetite and gastrointestinal motility: role of ghrelin-family peptides.

Eating disorders, obesity and cachexia endanger the lives of millions of people worldwide. Fortunately, in last decade, there has been a rapid and substantial progress toward uncovering the molecular and neural mechanisms by which energy imbalance develops. In 1999, ghrelin was identified as the first orexigenic gut-derived peptide. It stimulates appetite and controls the gastric motility and the acid secretion through the activation of the growth hormone secretagogue-receptor. After the discovery of ghrelin, other forms of ghrelin-related proteins were isolated from the rat stomach. The unmodified des-n-octanoyl form (des-acyl ghrelin) and the recent obestatin act through distinct receptors and contrarily to acyl ghrelin, show an anorexigenic activity. The finding that these three peptide hormones derive from the same precursor exert opposing physiological actions, highlights the importance of post-translational regulatory mechanisms. Further investigations are required to highlight the complexity of ghrelin physiology in order to better understand the mechanisms regulating the energy balance and provide a successful treatment of eating disorders, obesity and cachexia.

Growth hormone releasing peptide 2 reverses anorexia associated with chemotherapy with 5-fluoruracil in colon cancer cell-bearing mice.

The cancer-associated anorexia-cachexia syndrome is observed in 80% of patients with advanced-stage cancer, and is one of the major obstacles in chemotherapy. Ghrelin is a orexigenic hormone that has been proposed to prevent anorexia. Aim of the study was to determine whether the addition of the ghrelin agonist growth hormone releasing peptide 2 (GHRP-2) to cytotoxic therapy with 5-fluoruracil (5-FU) prevents the anorexia associated with chemotherapy in cancer cachectic mice. Thirty-three BALB/c female tumour-bearing mice were randomized to receive a solution containing: (a) placebo; (b) GHRP-2; (c) 5-FU; or (d) 5-FU+GHRP-2. Ten BALB/c no tumour-bearing mice received placebo solution. Food intake and survival were checked. Six hours after the drug injection the cumulative food intake was significantly increased in mice treated with the combination of 5-FU+GHRP-2 versus the 5-FU alone (P=0.0096). On day 3, the cumulative food intake of mice treated with GHRP-2, 5-FU and 5-FU+GHRP-2 significantly increased compared with naive and vehicle groups (P=0.0007, P=0.0038 and P=0.0166, respectively). The median survival time was longer in 5-FU+GHRP-2 treated mice than in those with 5-FU, although it was not significant (18 d versus 15.5 d, P=0.7). For the first time, we demonstrated that the addition of GHRP-2 to cytotoxic therapy with 5-FU improved appetite in tumour-bearing mice with anorexia/cachexia syndrome in early stage. These data suggest that GHRP-2 may improve the efficacy of therapy and the quality of life of cancer patients thank to the amelioration of their nutritional state.

Anorexia in cancer: role of feeding-regulatory peptides.

Anorexia is one of the most common symptoms in advanced cancer and is a frequent cause of discomfort for cancer patients and their families. The pathogenesis of cancer anorexia is multi-factorial and involves most of the hypothalamic neuronal signalling pathways modulating energy homeostasis. It is considered to be the result of a failure of usual appetite and satiety signals. Loss of appetite can arise from decreased taste and smell of food, as well as from dysfunctional hypothalamic signalling pathways and cytokine production. Cytokines in particular, appear to play a key role in energy balance through persistent activation of the melanocortin system and inhibition of the neuropeptide Y pathway. The imbalance between anorexigenic and orexigenic peptides leads to suppression of appetite, and increased satiety and satiation associated with marked weight loss and decline in physical performance. High levels of serotonin also appear to contribute to these effects and recent findings implicate corticotropin-releasing factor in the pathogenesis of cancer anorexia as well. Despite significant advances in our understanding of the regulation of food intake and energy expenditure, few effective therapies are available. A better appreciation of the molecular and neuronal mechanisms that control body weight homeostasis may lead to the development of new therapies for improving the survival and quality of life of these patients.

Phase II clinical trial of local use of GM-CSF for prevention and treatment of chemotherapy- and concomitant chemoradiotherapy-induced severe oral mucositis in advanced head and neck cancer patients: an evaluation of effectiveness, safety and costs.

In the present open non-randomized phase II study we looked for effectiveness, safety, tolerability and costs of locally applied GM-CSF in preventing or treating mucositis in patients receiving chemotherapy or chemoradiotherapy for head and neck cancer. In addition to clinical mucositis scoring system, the effects of treatment with GM-CSF were evaluated by its impact on patient quality of life and by laboratory immunological assays such as serum proinflammatory cytokines, IL-2 and leptin. The trial was designed to assess the effectiveness of local GM-CSF treatment in two different settings: i) prophylaxis of mucositis; ii) treatment of mucositis. Prophylaxis was chosen for chemoradiotherapy treatments of high mucosatoxic potential, while curative treatment was reserved for chemotherapy or chemoradiotherapy treatments of lesser potential of inducing mucositis. From January 1998 to December 2001, 68 patients entered the study. The great majority of patients of both groups had head and neck cancer, were stage IV, PS ECOG 0-1, were habitual smokers and were treated with chemotherapy and concomitant (or sequential) chemoradiotherapy. Forty-six patients were included in the 'prophylactic' setting and 22 patients in the 'curative' setting. The main findings of our study are: only 50% of patients included in the 'prophylactic' setting developed mucositis; the duration of oral mucositis from appearance until complete remission was significantly shorter in the 'prophylactic' than in the 'curative' setting; the mean grade of oral mucositis at baseline, on day 3 of therapy and on day 6 of therapy was significantly lower in the 'prophylactic' than in the 'curative' setting; 24 (55.82%) patients in the 'prophylactic' setting had grade 3/4 oral mucositis at baseline compared to 25 (80.60%) patients in the 'curative' setting (p=0.048). Thirteen (30.23%) patients in the 'prophylactic' setting had grade 3/4 oral mucositis on day 3 of therapy compared to 19 (61.29%) patients in the 'curative' setting (p=0.015); 'prophylactic' setting was able to shorten grade 3/4 oral mucositis to grade 0/1 more effectively than the 'curative' one on day 6 of therapy (p=0.05). The present clinical trial is to date by far the largest study assessing the effectiveness of topical GM-CSF and it is the first study comparing the efficacy of topical GM-CSF in the 'prophylactic' setting, i.e., with the aim to prevent the chemoradiotherapy-induced oral mucositis, with that in the 'curative' treatment, i.e., the therapy for established oral mucositis. The topical application of GM-CSF was demonstrated to be effective for oral mucositis induced by chemotherapy and chemoradiotherapy regimens. Moreover, the 'prophylactic' setting was demonstrated to be more effective than the 'curative' one.