Impact of Metformin Use and Diabetic Status During Adjuvant Fluoropyrimidine-Oxaliplatin Chemotherapy on the Outcome of Patients with Resected Colon Cancer: A TOSCA Study Subanalysis.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is associated with increased risk of colon cancer (CC), whereas metformin use seems to be protective. However, the impact of metformin use on the risk of death or disease recurrence after radical surgery for CC remains uncertain. MATERIALS AND METHODS: This is a substudy conducted in patients with high-risk stage II or stage III CC randomized in the TOSCA trial, which compared 3 versus 6 months of fluoropyrimidine-oxaliplatin adjuvant chemotherapy. Objective of the study was to investigate the impact of metformin exposure during adjuvant chemotherapy on overall survival (OS) and relapse-free survival (RFS). We also evaluated the impact of T2DM or metformin dosage on clinical outcomes. RESULTS: Out of 3,759 patients enrolled in the TOSCA trial, 133 patients with diabetes (9.2%) and 1,319 without diabetes (90.8%) were recruited in this study. After excluding 13 patients with diabetes without information on metformin exposure, 76 patients with T2DM (63.3%) were defined as metformin users and 44 (36.7%) as metformin nonusers. After a median follow-up of 60.4 months, 26 (21.7%) patients relapsed and 16 (13.3%) died. Metformin use was neither associated with OS (adjusted hazard ratio [HR], 1.51; 95% confidence interval [CI], 0.48-4.77; p = .4781) nor with RFS (HR, 1.56; 95% CI, 0.69-3.54; p = .2881). Similarly, we found no association between T2DM or metformin dosage and OS or RFS. CONCLUSIONS: Metformin use and T2DM did not impact on OS or RFS in patients with resected CC treated with adjuvant fluoropyrimidine-oxaliplatin chemotherapy. Larger studies and longer follow-up are required to clarify the potential efficacy of metformin in improving the prognosis of patients with CC. IMPLICATIONS FOR PRACTICE: The role of the antidiabetic drug metformin in colon cancer prevention and treatment is highly debated. While low-dose metformin reduced the incidence of colorectal adenomas in two prospective studies, its effect in patients with already established colon cancer remains unclear. In this study, the potential impact of metformin on the survival of resected colon cancer patients who received adjuvant chemotherapy was investigated in the context of the TOSCA study. We did not find any association between metformin use or dosages and patient survival. Prospective studies are required to draw definitive conclusions about metformin impact on colon cancer recurrence and survival.

Fluoropyrimidine-induced cardiotoxicity.

Fluoropyrimidines (5-fluorouracil and capecitabine) are antimetabolite drugs, widely used for the treatment of a variety of cancers, both in adjuvant and in metastatic setting. Although the most common toxicities of these drugs have been extensively studied, robust data and comprehensive characterization still lack concerning fluoropyrimidine-induced cardiotoxicity (FIC), an infrequent but potentially life-threatening toxicity. This review summarizes the current state of knowledge of FIC with special regard to proposed pathogenetic models (coronary vasospasm, endothelium and cardiomyocytes damage, toxic metabolites, dihydropyrimidine dehydrogenase deficiency); risk and predictive factors; efficacy and usefulness in detection of laboratory markers, electrocardiographic changes and cardiac imaging; and specific treatment, including a novel agent, uridine triacetate. The role of alternative chemotherapeutic options, namely raltitrexed and TAS-102, is discussed, and, lastly, we overview the most promising future directions in the research on FIC and development of diagnostic tools, including microRNA technology.

Synergy of molecular targeted approaches and immunotherapy in melanoma: preclinical basis and clinical perspectives.

INTRODUCTION: Targeted therapy and immunotherapies are the novel pharmacologic treatment strategies for metastatic melanoma. BRAF and MEK inhibitors effectively block the hyperactivation of the MAPK pathway in BRAF mutant melanomas and also have several other effects on melanoma cells and on the immune response. The aim of this work is to discuss the rationale, evidence and perspectives of approaches combining target and immunotherapy against melanoma. AREAS COVERED: We first review the effects of BRAF and MEK inhibitors on melanoma cells and on the different components of the immune system. Afterwards, we summarize the results of the preclinical and clinical studies that have combined targeted therapy and immunotherapy for the treatment of melanoma. EXPERT OPINION: Clinical applications of immunotherapy strategies have recently changed the therapeutic mainstay for metastatic melanoma. Biologic and initial preclinical data support their integration with innovative molecular targeted therapies, opening enormous perspectives for researchers in the effort of finding a definitive cure. Main open challenges are the definition of reliable research models, assessment of effective schedules, safety issues and designing of personalized approaches.

Sorafenib and everolimus for patients with unresectable high-grade osteosarcoma progressing after standard treatment: a non-randomised phase 2 clinical trial.

BACKGROUND: Results of previous study showed promising but short-lived activity of sorafenib in the treatment of patients with unresectable advanced and metastatic osteosarcoma. This treatment failure has been attributed to the mTOR pathway and might therefore be overcome with the addition of mTOR inhibitors. We aimed to investigate the activity of sorafenib in combination with everolimus in patients with inoperable high-grade osteosarcoma progressing after standard treatment. METHODS: We did this non-randomised phase 2 trial in three Italian Sarcoma Group centres. We enrolled adults (≥18 years) with relapsed or unresectable osteosarcoma progressing after standard treatment (methotrexate, cisplatin, and doxorubicin, with or without ifosfamide). Patients received 800 mg sorafenib plus 5 mg everolimus once a day until disease progression or unacceptable toxic effects. The primary endpoint was 6 month progression-free survival (PFS). All analyses were intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT01804374. FINDINGS: We enrolled 38 patients between June 16, 2011, and June 4, 2013. 17 (45%; 95% CI 28-61) of 38 patients were progression free at 6 months. Toxic effects led to dose reductions, or short interruptions, or both in 25 (66%) of 38 patients and permanent discontinuation for two (5%) patients. The most common grade 3-4 adverse events were lymphopenia and hypophosphataemia each in six (16%) patients, hand and foot syndrome in five (13%), thrombocytopenia in four (11%), and fatigue, oral mucositis, diarrhoea, and anaemia each in two (5%). One patient (3%) had a grade 3 pneumothorax that required trans-thoracic drainage, and that recurred at the time of disease progression. This was reported as a serious adverse event related to the study drugs in both instances. No other serious adverse events were reported during the trial. There were no treatment-related deaths. INTERPRETATION: Although the combination of sorafenib and everolimus showed activity as a further-line treatment for patients with advanced or unresectable osteosarcoma, it did not attain the prespecified target of 6 month PFS of 50% or greater. FUNDING: Italian Sarcoma Group.

Prospective phase II trial of neoadjuvant chemo-radiotherapy with Oxaliplatin and Capecitabine in locally advanced rectal cancer (XELOXART).

Neo-adjuvant chemo-radiotherapy (CT-RT) has been shown to decrease local recurrence rate in locally advanced rectal cancer. This multicenter phase II trial was conducted to evaluate the feasibility, safety and effectiveness of a combination of pre-operative radiotherapy and concurrent Capecitabine plus Oxaliplatin (XELOXART Trial). From October 2008 to May 2011, fifty consecutive patients affected with T3/T4 and/or N+ rectal cancer were enrolled. Treatment protocol consisted of 50.4 Gy in 28 fractions, Oxaliplatin 60 mg/m(2) once a week for 6 weeks and oral Capecitabine 825 mg/m(2) twice daily from day 1 to 14 and from day 22 to 35. Surgery was planned 6-8 weeks after. Main endpoints were pathological complete response rate (pCR) and the type of surgery performed compared to the planned one at diagnosis. 50 patients were included; pCR (ypT0N0M0) was achieved in 6 patients (12 %). Tumour downstaging was observed in 27 patients (54 %), and nodal downstaging in 32 patients (64 %). A total of 32 patients had lower rectal cancer, with 24 candidate for abdominal-perineal resection. At the end of CT-RT, a total of 12/24 (50 %) underwent conservative surgery. Grade 3 toxicity (fatigue and diarrhoea) occurred in 4 % of patients; grade 4 sensory neuropathy occurred in 2 % of patients. Perioperative complications of any grade occurred in 10 % of patients. Pre-operative CT-RT with Capecitabine-Oxaliplatin was well tolerated and resulted in an encouraging sphincter preservation and tumour downstaging rate. No improvements in terms of pathological complete response rate were shown.

The Combination of Sorafenib and Everolimus Abrogates mTORC1 and mTORC2 upregulation in osteosarcoma preclinical models.

PURPOSE: The multikinase inhibitor sorafenib displays antitumor activity in preclinical models of osteosarcoma. However, in sorafenib-treated patients with metastatic-relapsed osteosarcoma, disease stabilization and tumor shrinkage were short-lived and drug resistance occurred. We explored the sorafenib treatment escape mechanisms to overcome their drawbacks. EXPERIMENTAL DESIGN: Immunoprecipitation, Western blotting, and immunohistochemistry were used to analyze the mTOR pathway [mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2)]. Cell viability, colony growth, and cell migration were evaluated in different osteosarcoma cell lines (MNNG-HOS, HOS, KHOS/NP, MG63, U-2OS, SJSA-1, and SAOS-2) after scalar dose treatment with sorafenib (10-0.625 µmol/L), rapamycin-analog everolimus (100-6.25 nmol/L), and combinations of the two. Cell cycle, reactive oxygen species (ROS) production, and apoptosis were assessed by flow cytometry. Nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice injected with MNNG-HOS cells were used to determine antitumor and antimetastatic effects. Angiogenesis and vascularization were evaluated in vitro by exploiting endothelial branching morphogenesis assays and in vivo in xenografted mice and chorioallantoic membranes. RESULTS: After sorafenib treatment, mTORC1 signaling was reduced (downstream target P-S6), whereas mTORC2 was increased (phospho-mTOR Ser2481) in MNNG-HOS xenografts compared with vehicle-treated mice. Combining sorafenib with everolimus resulted in complete abrogation of both mTORC1 [through ROS-mediated AMP-activated kinase (AMPK) activation] and mTORC2 (through complex disassembly). The sorafenib/everolimus combination yielded: (i) enhanced antiproliferative and proapoptotic effects, (ii) impaired tumor growth, (iii) potentiated antiangiogenesis, and (iv) reduced migratory and metastatic potential. CONCLUSION: mTORC2 activation is an escape mechanism from sorafenib treatment. When sorafenib is combined with everolimus, its antitumor activity is increased by complete inhibition of the mTOR pathway in the preclinical setting.

Third-line sorafenib after sequential therapy with sunitinib and mTOR inhibitors in metastatic renal cell carcinoma.

BACKGROUND: Sunitinib and everolimus have been approved for first- and second-line treatment, respectively, in metastatic renal cell carcinoma (mRCC). The role of sorafenib, which is approved for second-line treatment after cytokines failure, is presently to be defined. OBJECTIVE: To determine whether third-line sorafenib after sequential use of sunitinib and mammalian target of rapamycin inhibitors (everolimus or temsirolimus) is feasible and effective. DESIGN, SETTING, AND PARTICIPANTS: One hundred fifty medical records of patients with mRCC treated with first-line sunitinib between January 2006 and January 2010 were reviewed at four participating centers. Data regarding patients treated with the sequence sunitinib-everolimus or temsirolimus-sorafenib were extracted. Central analysis of radiographic images was performed using RECIST criteria to determine progression-free survival (PFS) and overall response rate (oRR) to sorafenib treatment. MEASUREMENTS: PFS and oRR to sorafenib were the primary end points. Secondary outcomes were safety and overall survival (OS). RESULTS AND LIMITATIONS: Thirty-four patients were eligible for the study. A median PFS of 4 mo (range: 3-6 mo) and a median OS of 7 mo since sorafenib treatment (range: 6-10 mo) were reported. Of the patients, 23.5% showed response to sorafenib, with an overall disease control rate (complete responses plus partial responses plus stable disease) of 44%. Selection bias, data incompleteness, and absence of study design are inevitable limitations of the study, although central review can strengthen the quality of presented data. CONCLUSIONS: Third-line sorafenib appears to be active and well tolerated in mRCC after first-line sunitinib and second-line everolimus or temsirolimus, with no patients interrupting sorafenib because of toxicity or lack of compliance. Prospective, placebo-controlled trials are completely lacking and are required in this setting.

Sorafenib blocks tumour growth, angiogenesis and metastatic potential in preclinical models of osteosarcoma through a mechanism potentially involving the inhibition of ERK1/2, MCL-1 and ezrin pathways.

BACKGROUND: Osteosarcoma (OS) is the most common primary bone tumour in children and young adults. Despite improved prognosis, metastatic or relapsed OS remains largely incurable and no significant improvement has been observed in the last 20 years. Therefore, the search for alternative agents in OS is mandatory. RESULTS: We investigated phospho-ERK 1/2, MCL-1, and phospho-Ezrin/Radixin/Moesin (P-ERM) as potential therapeutic targets in OS. Activation of these pathways was shown by immunohistochemistry in about 70% of cases and in all OS cell lines analyzed. Mutational analysis revealed no activating mutations in KRAS whereas BRAF gene was found to be mutated in 4/30 OS samples from patients. Based on these results we tested the multi-kinase inhibitor sorafenib (BAY 43-9006) in preclinical models of OS. Sorafenib inhibited OS cell line proliferation, induced apoptosis and downregulated P-ERK1/2, MCL-1, and P-ERM in a dose-dependent manner. The dephosphorylation of ERM was not due to ERK inhibition. The downregulation of MCL-1 led to an increase in apoptosis in OS cell lines. In chick embryo chorioallantoic membranes, OS supernatants induced angiogenesis, which was blocked by sorafenib and it was also shown that sorafenib reduced VEGF and MMP2 production. In addition, sorafenib treatment dramatically reduced tumour volume of OS xenografts and lung metastasis in SCID mice. CONCLUSION: In conclusion, ERK1/2, MCL-1 and ERM pathways are shown to be active in OS. Sorafenib is able to inhibit their signal transduction, both in vitro and in vivo, displaying anti-tumoural activity, anti-angiogenic effects, and reducing metastatic colony formation in lungs. These data support the testing of sorafenib as a potential therapeutic option in metastatic or relapsed OS patients unresponsive to standard treatments.