Farsighted Stable Sets

A coalition is usually called stable if nobody has an immediate incentive to leave or to enter the coalition since he does not improve his payoff. This myopic behaviour does not consider further deviations which can take place after the first move. Chwe (1994) incorporated the idea of a farsighted behaviour in his definition of large consistent set (LCS). In some respects, we propose a different idea of dominance relation based on indirect dominance and on a different concept of belief on moving coalitions' behavior. A notion of stability for a coalitional game is introduced by taking into account the different degree of risk/safety of any player participating in a move. Some results about uncovered sets, internal stability are investigated. By exploiting our dominance and stability concepts, the prisoner's dilemma in coalitional form and its Nash equilibrium are studied. Some examples illustrating the differences between the largest consistent set, our stable set and stable set due to von Neumann and Morgenstern (1947) are presented.

The peculiar structural features of kiwi fruit pectin methylesterase: amino acid sequence, oligosaccharides structure, and modeling of the interaction with its natural proteinaceous inhibitor

Pectin methylesterase (PME) from kiwi fruit (Actinidia deliciosa) is a glycoprotein, showing an apparent molecular mass of 50 kDa upon size exclusion chromatography and SDS-PAGE. The primary structure, elucidated by direct sequencing of the protein, comprises 321 amino acid residues providing a molecular mass of 35 kDa. The protein has an acetylated Thr residue at the amino terminus and five N-glycosylation consensus sequences, four of which are actually glycosylated. A careful investigation of the oligosaccharide structures demonstrated that PME glycans belong to complex type oligosaccharides essentially consisting of xylosylated polyfucosylated biantennary structures. Alignment with known mature plant PME sequences indicates that the postulated active site residues are conserved. Kiwi PME activity is inhibited following the interaction with the proteinaceous inhibitor PMEI, isolated from the same source. Gel-filtration experiments show that kiwi PME/PMEI complex is stable in a large pH range and dissociates only at pH 10.0. Modeling of the interaction with the inhibitor was performed by using the crystal structure of the complex between kiwi PMEI and tomato PME as a template. The model shows that the binding site is the same reported for tomato PME. However, additional salt link interactions are found to connect the external loops of kiwi PME to PMEI. This finding may explain the higher pH stability of the complex formed by the two kiwi proteins respect to that formed by PMEI and tomato PME

Have There Been any Changes in the Epidemiology and Etiology of Maxillofacial Trauma During the COVID-19 Pandemic? An Italian Multicenter Study

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had a significant impact on people's behavior. The aim of this study has been to evaluate how the SARS-CoV-2 pandemic has impacted the incidence and the features of maxillofacial fractures presented at 6 Italian tertiary centers. Clinical records of all the patients diagnosed for facial fractures between February 23 and May 23, 2019 and 2020 were retrospectively reviewed. Any differences in patient number and characteristics and fracture etiology and site between the 2 groups were then statistically analyzed.There has been a 69.1% decrease in the number of incoming patients during the pandemic. The number of foreign patients has decreased significantly (23.3% versus 9.6%, P\u200a=\u200a0.011) while the average age has increased (38.6 versus 45.6 years old, P\u200a=\u200a0.01). Specific statistical significant differences for accidental falls (31.8% versus 50.1%, P\u200a=\u200a0.005) and sports injuries (16.9% versus 1.4%, P\u200a<\u200a0.001) were found. Concerning fracture sites, significant differences have been found in relation to nasal (22.5% versus 11.4%, P\u200a=\u200a0.009) and frontal sinus (0.9% versus 4.4%, P\u200a=\u200a0.037) fractures. In conclusion, SARS-CoV-2 pandemic has significantly changed the epidemiology and the etiology of facial traumas

Phase II Randomized Study of Vandetanib Plus Gemcitabine or Gemcitabine Plus Placebo as First-Line Treatment of Advanced Non–Small-Cell Lung Cancer in Elderly Patients

Introduction:The aim of the present study was to evaluate the efficacy and tolerability of vandetanib plus gemcitabine (V/G) compared with gemcitabine alone in elderly patients with untreated advanced non–small-cell lung cancer.Methods:This was a phase II, randomized, double-blind study. A total of 124 elderly patients (mean age, 75 yr; age range, 70–84 yr; 73% men) received V/G (n = 61) or placebo plus gemcitabine (n = 63). Progression-free survival (PFS) was the primary endpoint. Secondary endpoints were overall survival, objective response rate, duration of response, disease control rate, time to deterioration of performance status, and safety outcomes.Results:PFS was significantly prolonged with V/G (median, 183 days; 95% confidence interval, 116–214) compared with placebo plus gemcitabine (median, 169 days; 95% confidence interval, 95–194; p = 0.047). No statistically significant differences between arms were observed in all secondary endpoints, including overall survival. The addition of vandetanib to gemcitabine was well tolerated. The rate of patients with ≥1 treatment-related adverse event was comparable in the two arms, pyrexia, dyspnea, and neutropenia being the most common adverse events.Conclusions:V/G combination was associated with a statistically significant prolongation of PFS compared with gemcitabine alone in untreated elderly patients with advanced non–small-cell lung cancer, with an acceptable safety profile

Valproic Acid Synergizes With Cisplatin and Cetuximab in vitro and in vivo in Head and Neck Cancer by Targeting the Mechanisms of Resistance

Recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC) is a devastating malignancy with a poor prognosis. The combination of cisplatin (CDDP) plus cetuximab (CX) is one of the standard first-line treatments in this disease. However, this therapeutic regimen is often associated with high toxicity and resistance, suggesting that new combinatorial strategies are needed to improve its therapeutic index. In our study, we evaluated the antitumor effects of valproic acid (VPA), a well-known antiepileptic agent with histone deacetylase inhibitory activity, in combination with CDDP/CX doublet in head and neck squamous cell carcinoma (HNSCC) models. We demonstrated, in HNSCC cell lines, but not in normal human fibroblasts, that simultaneous exposure to equitoxic doses of VPA plus CDDP/CX resulted in a clear synergistic antiproliferative and pro-apoptotic effects. The synergistic antitumor effect was confirmed in four different 3D-self-assembled spheroid models, suggesting the ability of the combined approach to affect also the cancer stem cells compartment. Mechanistically, VPA enhanced DNA damage in combination treatment by reducing the mRNA expression of ERCC Excision Repair 1, a critical player in DNA repair, and by increasing CDDP intracellular concentration via upregulation at transcriptional level of CDDP influx channel copper transporter 1 and downregulation of the ATPAse ATP7B involved in CDDP-export. Valproic acid also induced a dose-dependent downregulation of epidermal growth factor receptor (EGFR) expression and of MAPK and AKT downstream signaling pathways and prevent CDDP- and/or CX-induced EGFR nuclear translocation, a well-known mechanism of resistance to chemotherapy. Indeed, VPA impaired the transcription of genes induced by non-canonical activity of nuclear EGFR, such as cyclin D1 and thymidylate synthase. Finally, we confirmed the synergistic antitumor effect also in vivo in both heterotopic and orthotopic models, demonstrating that the combined treatment completely blocked HNSCC xenograft tumors growth in nude mice. Overall, the introduction of a safe and generic drug such as VPA into the conventional treatment for R/M HNSCC represents an innovative and feasible antitumor strategy that warrants further clinical evaluation. A phase II clinical trial exploring the combination of VPA and CDDP/CX in R/M HNSCC patients is currently ongoing in our institute

Establishment of patient-derived tumor organoids to functionally inform treatment decisions in metastatic colorectal cancer

Colorectal cancer; Personalized medicine; ResistanceCáncer colorrectal; Medicina personalizada; ResistenciaCàncer colorectal; Medicina personalitzada; ResistènciaBackground Metastatic colorectal cancer (mCRC) patients tend to have modest benefits from molecularly driven therapeutics. Patient-derived tumor organoids (PDTOs) represent an unmatched model to elucidate tumor resistance to therapy, due to their high capacity to resemble tumor characteristics. Materials and methods We used viable tumor tissue from two cohorts of patients with mCRC, naïve or refractory to treatment, respectively, for generating PDTOs. The derived models were subjected to a 6-day drug screening assay (DSA) with a comprehensive pipeline of chemotherapy and targeted drugs against almost all the actionable mCRC molecular drivers. For the second cohort DSA data were matched with those from PDTO genotyping. Results A total of 40 PDTOs included in the two cohorts were derived from mCRC primary tumors or metastases. The first cohort included 31 PDTOs derived from patients treated in front line. For this cohort, DSA results were matched with patient responses. Moreover, RAS/BRAF mutational status was matched with DSA cetuximab response. Ten out of 12 (83.3%) RAS wild-type PDTOs responded to cetuximab, while all the mutant PDTOs, 8 out of 8 (100%), were resistant. For the second cohort (chemorefractory patients), we used part of tumor tissue for genotyping. Four out of nine DSA/genotyping data resulted applicable in the clinic. Two RAS-mutant mCRC patients have been treated with FOLFOX–bevacizumab and mitomycin–capecitabine in third line, respectively, based on DSA results, obtaining disease control. One patient was treated with nivolumab–second mitochondrial-derived activator of caspases mimetic (phase I trial) due to high tumor mutational burden at genotyping, experiencing stable disease. In one case, the presence of BRCA2 mutation correlated with DSA sensitivity to olaparib; however, the patient could not receive the therapy. Conclusions Using CRC as a model, we have designed and validated a clinically applicable methodology to potentially inform clinical decisions with functional data. Undoubtedly, further larger analyses are needed to improve methodology success rates and propose suitable treatment strategies for mCRC patients.This Translational Research Fellowship Project was supported by the ESMO with the aid of a grant from Amgen, by the Accelerator (ACRCelerator) [grant number A26825] and Ayuda a médicos jóvenes investigadores from Fundacion Científica—Asociacion Española Contra el Cancer (FC-AECC)/Associazione Italiana per la Ricerca sul Cancro (AIRC)/Cancer Research United Kingdom (CRUK) and by Familia Armangué. Any views, opinions, findings, conclusions or recommendations expressed in this material are those solely of the author(s) and do not necessarily reflect those of ESMO or Amgen. We thank Regione Campania (I-Cure Research Project) [grant number: Cup 21C17000030007], ESMO Translational Research Fellowship Program

BAD: a good therapeutic target?

The major goal in cancer treatment is the eradication of tumor cells. Under stress conditions, normal cells undergo apoptosis; this property is fortunately conserved in some tumor cells, leading to their death as a result of chemotherapeutic and/or radiation-induced stress. Many malignant cells, however, have developed ways to subvert apoptosis, a characteristic that constitutes a major clinical problem. Gilmore et al. recently described the ability of ZD1839, a small-molecule inhibitor of the epidermal growth factor receptor (EGFR), to induce apoptosis of mammary cells that are dependent upon growth factors for survival. Furthermore, they showed that the major effector of the EGFR-targeted therapy is BAD, a widely expressed BCL-2 family member. These results are promising in light of the role of the EGFR in breast cancer development

Chromogenic in situ hybridization to detect EGFR gene copy number in cell blocks from fine-needle aspirates of non small cell lung carcinomas and lung metastases from colo-rectal cancer

<p>Abstract</p> <p>Background</p> <p>Several studies demonstrated that epidermal growth factor receptor (EGFR) gene copy number (GCN) correlates to the response to tyrosine kinase inhibitors in non small cell lung cancer (NSCLC) and to anti-EGFR monoclonal antibodies (MoAbs) in metastatic colorectal cancer (CRC). In the presence of lung nodules, cytology is often the only possible diagnostic approach. Chromogenic <it>in situ </it>hybridization (CISH) is an alternative technique to fluorescence <it>in situ </it>hybridization (FISH), but its feasibility in detecting EGFR GCN in cell blocks from fine-needle aspiration cytology (FNAC) of lung nodules has not yet been established.</p> <p>Methods</p> <p>We evaluated the feasibility of CISH on 33 FNAC from 20 primary NSCLC (5 squamous carcinomas, 8 large cell carcinomas and 7 adenocarcinomas) and 13 lung metastases from CRC.</p> <p>Results</p> <p>Of the 33 FNAC analyzed by CISH, 27 (82%) presented a balanced increase in EGFR gene and chromosome 7 number: 10 cases (30%) showed a low polysomy, 15 (45%) a high polysomy and 2 (6%) NSCLC were amplified. No significant differences between NSCLC and CRC lung metastases were found in relation to disomic or polysomic status. In addition, no correlation between EGFR GCN and EGFR immunohistochemical overexpression was found. Furthermore, we compared CISH results with those obtained by FISH on the same samples and we found 97% overall agreement between the two assays (k = 0.78, p < 0.0001). Two cases were amplified with both assays, whereas 1 case of NSCLC was amplified by FISH only. CISH sensitivity was 67%, the specificity and positive predictive value (PPV) was 100%, and the negative predictive value (NPV) was 97%.</p> <p>Conclusions</p> <p>Our study shows that CISH is a valid method to detect EGFR GCN in cell blocks from FNAC of primary NSCLC or metastatic CRC to the lung.</p

Biomarkers Predicting Clinical Outcome of Epidermal Growth Factor Receptor–Targeted Therapy in Metastatic Colorectal Cancer

The monoclonal antibodies panitumumab and cetuximab that target the epidermal growth factor receptor (EGFR) have expanded the range of treatment options for metastatic colorectal cancer. Initial evaluation of these agents as monotherapy in patients with EGFR-expressing chemotherapy-refractory tumors yielded response rates of approximately 10%. The realization that detection of positive EGFR expression by immunostaining does not reliably predict clinical outcome of EGFR-targeted treatment has led to an intense search for alternative predictive biomarkers. Oncogenic activation of signaling pathways downstream of the EGFR, such as mutation of KRAS, BRAF, or PIK3CA oncogenes, or inactivation of the PTEN tumor suppressor gene is central to the progression of colorectal cancer. Tumor KRAS mutations, which may be present in 35%–45% of patients with colorectal cancer, have emerged as an important predictive marker of resistance to panitumumab or cetuximab treatment. In addition, among colorectal tumors carrying wild-type KRAS, mutation of BRAF or PIK3CA or loss of PTEN expression may be associated with resistance to EGFR-targeted monoclonal antibody treatment, although these additional biomarkers require further validation before incorporation into clinical practice. Additional knowledge of the molecular basis for sensitivity or resistance to EGFR-targeted monoclonal antibodies will allow the development of new treatment algorithms to identify patients who are most likely to respond to treatment and could also provide rationale for combining therapies to overcome primary resistance. The use of KRAS mutations as a selection biomarker for anti-EGFR monoclonal antibody (eg, panitumumab or cetuximab) treatment is the first major step toward individualized treatment for patients with metastatic colorectal cancer

Cetuximab continuation after first progression in metastatic colorectal cancer (CAPRI-GOIM): A randomized phase II trial of FOLFOX plus cetuximab versus FOLFOX

Background: Cetuximab plus chemotherapy is a first-line treatment option in metastatic KRAS and NRAS wild-type colorectal cancer (CRC) patients. No data are currently available on continuing anti-epidermal growth factor receptor (EGFR) therapy beyond progression. Patients and methods: We did this open-label, 1:1 randomized phase II trial at 25 hospitals in Italy to evaluate the efficacy of cetuximab plus 5-fluorouracil, folinic acid and oxaliplatin (FOLFOX) as second-line treatment of KRAS exon 2 wild-type metastatic CRC patients treated in first line with 5-fluorouracil, folinic acid and irinotecan (FOLFIRI) plus cetuximab. Patients received FOLFOX plus cetuximab (arm A) or FOLFOX (arm B). Primary end point was progressionfree survival (PFS). Tumour tissues were assessed by next-generation sequencing (NGS). This report is the final analysis. Results: Between 1 February 2010 and 28 September 2014, 153 patients were randomized (74 in arm A and 79 in arm B). Median PFS was 6.4 [95% confidence interval (CI) 4.7-8.0] versus 4.5 months (95% CI 3.3-5.7); [hazard ratio (HR), 0.81; 95% CI 0.58-1.12; P = 0.19], respectively. NGS was performed in 117/153 (76.5%) cases; 66/117 patients (34 in arm A and 32 in arm B) had KRAS, NRAS, BRAF and PIK3CA wild-type tumours. For these patients, PFS was longer in the FOLFOX plus cetuximab arm [median 6.9 (95% CI 5.5-8.2) versus 5.3 months (95% CI 3.7-6.9); HR, 0.56 (95% CI 0.33-0.94); P = 0.025]. There was a trend in better overall survival: median 23.7 [(95% CI 19.4-28.0) versus 19.8 months (95% CI 14.9-24.7); HR, 0.57 (95% CI 0.32-1.02); P = 0.056]. Conclusions: Continuing cetuximab treatment in combination with chemotherapy is of potential therapeutic efficacy in molecularly selected patients and should be validated in randomized phase III trials