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Exosomes mediate cell-to-cell crosstalk involving a variety of biomolecules through an intricate signaling network. In recent years, the pivotal role of exosomes and their non-coding RNAs cargo in the development and progression of several cancer types clearly emerged. In particular, tumor bulk and its microenvironment co-evolve through cellular communications where these nanosized extracellular vesicles are among the most relevant actors. Knowledge about the cellular, and molecular mechanisms involved in these communications will pave the way for novel exosome-based delivery of therapeutic RNAs as well as innovative prognostic/diagnostic tools. Despite the valuable therapeutic potential and clinical relevance of exosomes, their role on sarcoma has been vaguely reported because the rarity and high heterogeneity of this type of cancer. Here, we dissected the scientific literature to unravel the multifaceted role of exosomal non-coding RNAs as mediator of cell-to-cell communications in the sarcoma subtypes.
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Comunicación Celular , Exosomas , ARN no Traducido , Sarcoma , Humanos , Exosomas/metabolismo , Exosomas/genética , Sarcoma/genética , Sarcoma/patología , Sarcoma/terapia , Sarcoma/metabolismo , ARN no Traducido/genética , Animales , Microambiente Tumoral/genética , Regulación Neoplásica de la Expresión Génica , Transducción de Señal , Biomarcadores de Tumor/genética , Investigación Biomédica TraslacionalRESUMEN
The present case report is aimed to highlight the difficulty and the reason for the delayed diagnosis of phosphaturic mesenchymal tumors, emphasizing the need of standardized protocols for diagnosis, surgery and follow-up in high-volume hospitals. The clinical signs and symptoms, diagnostic and therapeutic procedures, immunohistological features were analyzed. Delayed diagnosis of phosphaturic mesenchymal tumor was primarily due to non-specific clinical symptoms such as fatigue, muscular and bone pain, and multiple fractures. This cryptic clinical picture made the diagnosis tricky that led to treatment of patient for non-specific pain and stress fractures before to consider the tumor-induced osteomalacia syndrome. Some well-documented studies were found in the literature in which the history of trauma is a critical trigger of glomus tumors. Extra-subungual tumors most frequently occur in the knee and ankle regions, particularly among young adults, and the diagnosis is typically made approximately 7.2 years after initial symptom onset. The difficult tumor localization represented an additional obstacle to the prompt treatment, leading to delayed curative surgery.
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The correlation between cancer and venous thromboembolism (VTE) is solid, whereas the knowledge about cancer-related arterial thromboembolism (ATE) still needs a deeper investigation to clarify its pathogenesis. We describe two cases that represent useful hints for a comprehensive review of the thrombotic issue. A 75-year-old man with advanced rectal cancer treated with fluoropyrimidines suffered two catheter-related VTE events managed according to current guidelines. There was no indication for "extended" anticoagulant therapy for him, but during antithrombotic wash-out and fluoropyrimidines plus panitumumab regimen, he suffered a massive right coronary artery (RCA) thrombosis. Another patient with no cardiovascular (CV) risk factors and affected by advanced bladder cancer was treated with a platinum-containing regimen and suffered an acute inferior myocardial infarction 2 days after chemotherapy administration. He was successfully treated with primary Percutaneous Transluminal Coronary Angioplasty of RCA, discontinuing platinum-based therapy. Our observations raise the issue of cancer-associated thrombosis (CAT) complexity and the potential correlation between arterial and venous thrombotic events. Moreover, physicians should be aware of the thrombotic risk associated with anticancer therapies, suggesting that an appropriate prophylaxis should be considered.
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Background and objective: The oncogenic effect of ionizing radiation is widely known. Sarcomas developing after radiation therapy (RT), termed "iatrogenic disease of success", represent a growing problem, since the advancements in cancer management and screening programs have increased the number of long-term cancer survivors. Although many patients have been treated with radiation therapy, only few data are available on radiation-induced sarcomas (RIS). Methods: We examined the medical and radiological records of 186 patients with histologically proven soft tissue and bone sarcomas, which referred to IRCCS CROB Centro di Riferimento Oncologico della Basilicata from January 2009 to May 2022. Among them, seven patients received a histological diagnosis of secondary RIS, according to Cahan's criteria. Clinicopathological features and treatment follow-up data of RIS patients were retrospectively analyzed. Results: Among these secondary RIS, five arose in irradiated breast cancer (5/2,570, 0.19%) and two in irradiated head and neck cancer (2/1,986, 0.10%) patients, with a mean onset latency time of 7.3 years. The histology of RIS was one desmoid tumor, two angiosarcomas, one chondrosarcoma, two leiomyosarcomas, and one undifferentiated pleomorphic sarcoma. Out of the seven RIS, one received radiotherapy, one received electrochemotherapy (ECT), one received a second-line chemotherapy, three were subjected to three lines of chemotherapy, and one underwent radiofrequency ablation, chemotherapy, and ECT. Median survival time is 36 months. No significant survival differences were found stratifying patients for age at RT, latency time, and age at RIS diagnosis. Conclusions: RIS represents a possible complication for long-survivor cancer patients. Therefore, adherence to a strict follow-up after the radiation treatment is recommended to allow early diagnosis and optimal management of RIS patients. After the planned follow-up period, considering the long-term risk to develop a RIS, a specific multispecialty survivorship care plan could be of benefit for patients.
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Epithelioid sarcoma (ES) is a rare disease representing <1% of soft tissue sarcomas. Current therapies are based on anthracycline alone or in combination with ifosfamide or other cytotoxic drugs. ES is still characterized by a poor prognosis with high rates of recurrence. Indeed, for years, ES survival rates have remained stagnant, suggesting that conventional treatments should be revised and improved. New therapeutic approaches are focused to target the key regulators of signaling pathways, the causative markers of tumor pathophysiology. To this end, we selected, among the drugs to which an ES cell line is highly sensitive, those that target signaling pathways known to be dysregulated in ES. In particular, we found a key role for GSK-3ß, which results in up-regulation in tumor versus normal tissue samples and associated to poor prognosis in sarcoma patients. Following this evidence, we evaluated CHIR99021, a GSK-3 inhibitor, as a potential drug for use in ES therapy. Our data highlight that, in ES cells, CHIR99021 induces cell cycle arrest, mitotic catastrophe (MC) and autophagic response, resulting in reduced cell proliferation. Our results support the potential efficacy of CHIR99021 in ES treatment and encourage further preclinical and clinical studies.
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Autofagia/efectos de los fármacos , Mitosis/efectos de los fármacos , Piridinas/farmacología , Pirimidinas/farmacología , Sarcoma/patología , Neoplasias de los Tejidos Blandos/patología , Adulto , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Glucógeno Sintasa Quinasa 3 beta/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3 beta/fisiología , Humanos , Moduladores de la Mitosis/farmacología , Sarcoma/mortalidad , Neoplasias de los Tejidos Blandos/mortalidad , Análisis de SupervivenciaRESUMEN
BACKGROUND: Previous studies on oxaliplatin and fluoropyrimidines as adjuvant therapy in older patients with stage III colon cancer (CC) produced conflicting results. PATIENTS AND METHODS: We assessed the impact of age on time to tumour recurrence (TTR), disease-free survival (DFS), cancer-specific survival (CSS), and overall survival (OS) in 2360 patients with stage III CC (1667 aged <70 years and 693 ≥ 70 years) randomised to receive 3 or 6 months of FOLFOX or CAPOX within the frame of the phase III, TOSCA study. RESULTS: Older patients compared with younger ones presented more frequently an Eastern Cooperative Oncology Group performance status equal to 1 (10.5% vs 3.3%, p < 0.001), a greater number of right-sided tumours (40.9% vs 26.6%, p < 0.001), and were at higher clinical risk (37.2% vs 33.2%, p = 0.062). The treatments were almost identical in the two cohorts (p = 0.965). We found a greater proportion of dose reductions (46.7% vs 41.4%, p = 0.018), treatment interruptions (26.1% vs 19.3%, p < 0.001) and a higher proportion of recurrences (24.2% vs 20.3%, p = 0.033) in the older patients. The multivariable analysis of the TTR did not indicate a statistically significant effect of age (hazard ratio [HR]: 1.19; 95% confidence interval [CI]: 0.98-1.44; p = 0.082). The HR comparing older with younger patients was 1.34 (95% CI: 1.12-1.59; p = 0.001) for DFS, 1.58 (95% CI: 1.26-1.99; p < 0.001) for OS, and 1.28 (95% CI: 0.96-1.70; p = 0.089) for CSS. CONCLUSIONS: Worse prognostic factors and reduced treatment compliance have a negative impact on the efficacy of oxaliplatin-based adjuvant therapy in older patients.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante/mortalidad , Neoplasias del Colon/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Capecitabina/administración & dosificación , Neoplasias del Colon/patología , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Oxaliplatino/administración & dosificación , Pronóstico , Tasa de SupervivenciaRESUMEN
Detailed knowledge on the formation of biomembrane domains, their structure, composition, and physical characteristics is scarce. Despite its frequently discussed importance in signaling, e.g., in obtaining localized non-homogeneous receptor compositions in the plasma membrane, the nanometer size as well as the dynamic and transient nature of domains impede their experimental characterization. In turn, atomistic molecular dynamics (MD) simulations combine both, high spatial and high temporal resolution. Here, using microsecond atomistic MD simulations, we characterize the spontaneous and unbiased formation of nano-domains in a plasma membrane model containing phosphatidylcholine (POPC), palmitoyl-sphingomyelin (PSM), and cholesterol (Chol) in the presence or absence of the neurotransmitter serotonin at different temperatures. In the ternary mixture, highly ordered and highly disordered domains of similar composition coexist at 303 K. The distinction of domains by lipid acyl chain order gets lost at lower temperatures of 298 and 294 K, suggesting a phase transition at ambient temperature. By comparison of domain ordering and composition, we demonstrate how the domain-specific binding of the neurotransmitter serotonin results in a modified domain lipid composition and a substantial downward shift of the phase transition temperature. Our simulations thus suggest a novel mode of action of neurotransmitters possibly of importance in neuronal signal transmission.
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Unsaturated and saturated phospholipids tend to laterally segregate, especially in the presence of cholesterol. Small molecules such as neurotransmitters, toxins, drugs etc. possibly modulate this lateral segregation. The small aromatic neurotransmitter serotonin (5-HT) has been found to bind to membranes. We studied the lipid structure and packing of a ternary membrane mixture consisting of palmitoyl-oleoyl-phosphatidylcholine, palmitoyl-sphingomyelin, and cholesterol at a molar ratio of 4/4/2 in the absence and in the presence of 5-HT, using a combination of solid-state 2H NMR, atomic force microscopy, and atomistic molecular dynamics (MD) simulations. Both NMR and MD report formation of a liquid ordered (L o ) and a liquid disordered (L d ) phase coexistence with small domains. Lipid exchange between the domains was fast such that single component 2H NMR spectra are detected over a wide temperature range. A drastic restructuring of the domains was induced when 5-HT is added to the membranes at a 9 mol% concentration relative to the lipids. 2H NMR spectra of all components of the mixture showed two prominent contributions indicative of molecules of the same kind residing both in the disordered and the ordered phase. Compared to the data in the absence of 5-HT, the lipid chain order in the disordered phase was further decreased in the presence of 5-HT. Likewise, addition of serotonin increased lipid chain order within the ordered phase. These characteristic lipid chain order changes were confirmed by MD simulations. The 5-HT-induced larger difference in lipid chain order results in more pronounced differences in the hydrophobic thickness of the individual membrane domains. The correspondingly enlarged hydrophobic mismatch between ordered and disordered phases is assumed to increase the line tension at the domain boundary, which drives the system into formation of larger size domains. These results not only demonstrate that small membrane binding molecules such as neurotransmitters have a profound impact on essential membrane properties. It also suggests a mechanism by which the interaction of small molecules with membranes can influence the function of membrane proteins and non-cognate receptors. Altered membrane properties may modify lateral sorting of membrane protein, membrane protein conformation, and thus influence their function as suspected for neurotransmitters, local anesthetics, and other small drug molecules.
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Store-operated calcium entry (SOCE) through STIM-gated ORAI channels governs vital cellular functions. In this context, SOCE controls cellular redox signaling and is itself regulated by redox modifications. However, the molecular mechanisms underlying this calcium-redox interplay and the functional outcomes are not fully understood. Here, we examine the role of STIM2 in SOCE redox regulation. Redox proteomics identify cysteine 313 as the main redox sensor of STIM2 in vitro and in vivo. Oxidative stress suppresses SOCE and calcium currents in cells overexpressing STIM2 and ORAI1, an effect that is abolished by mutation of cysteine 313. FLIM and FRET microscopy, together with MD simulations, indicate that oxidative modifications of cysteine 313 alter STIM2 activation dynamics and thereby hinder STIM2-mediated gating of ORAI1. In summary, this study establishes STIM2-controlled redox regulation of SOCE as a mechanism that affects several calcium-regulated physiological processes, as well as stress-induced pathologies.
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Calcio/metabolismo , Molécula de Interacción Estromal 2/metabolismo , Canales de Calcio/metabolismo , Señalización del Calcio , Línea Celular Tumoral , Cisteína/metabolismo , Humanos , Proteínas Sensoras del Calcio Intracelular/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteína ORAI1/metabolismo , Oxidación-Reducción , Estrés Oxidativo/fisiología , Molécula de Interacción Estromal 1/genética , Molécula de Interacción Estromal 1/metabolismo , Molécula de Interacción Estromal 2/genética , Molécula de Interacción Estromal 2/fisiologíaRESUMEN
BACKGROUND: Although American Society of Clinical Oncology and European Society for Medical Oncology guidelines have identified the negative prognostic factors that clinicians have to consider when treating their patients with stage II colon cancer (CC), the role of histological subtype is controversial. SUBJECTS, MATERIALS, AND METHODS: The randomized, multicenter, phase III TOSCA trial compared 3 versus 6 months of fluoropyrimidine-oxaliplatin adjuvant chemotherapy in 3,759 patients with high-risk stage II or stage III CC. The objective of this substudy was to evaluate the influence of histological subtypes on the impact of the treatment duration of adjuvant chemotherapy in terms of relapse-free survival (RFS) and overall survival (OS) in 85 mucinous adenocarcinoma (MUC) and 389 nonmucinous adenocarcinoma (NMUC) patients with high-risk stage II, grade 3 CC. RESULTS: A significant interaction between treatment duration and histology was observed in both RFS (p = .027) and OS (p = .017). In the subgroup of patients with MUC, worse RFS (adjusted hazard ratio [HR], 3.95; 95% confidence interval [CI], 1.03-15.17; p = .045) and OS (HR, 9.56; 95% CI, 1.14-79.98; p = .037) were detected for patients treated in the 3-month arm. No statistically significant differences were found in the subgroup of patients with NMUC. CONCLUSION: Patients with MUC, grade 3, stage II CC require special attention and may need 6 months of oxaliplatin-based chemotherapy. Larger studies are required to assess the combined use of histology and other prognostic/predictive factors to define the administration of chemotherapy in patients with stage II CC and to improve their prognosis. IMPLICATIONS FOR PRACTICE: Although ASCO and ESMO guidelines define the prognostic factors for patients with stage II colon cancer to establish the use of adjuvant chemotherapy, the influence of histological subtypes is controversial in this population. This study underscores that patients with grade 3 mucinous adenocarcinomas may need adjuvant chemotherapy with oxaliplatin and fluoropyrimidines for a duration of 6 months rather than 3 months.
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Adenocarcinoma , Neoplasias del Colon , Adenocarcinoma/patología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Fluorouracilo/uso terapéutico , Humanos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Oxaliplatino/uso terapéutico , PronósticoRESUMEN
BACKGROUND: In our surgical daily activity, we report the observation of rare tumour as Gastrointestinal Stromal Tumours (GIST). We report the incidence and behaviour of new cases of GIST operated in our Center during the last decade, from 2008 to 2018 and here we also describe the concomitant observation of a second gastroenteric tumor. METHOD: We have examined all the case files and histological examinations of patients with CD 117-positive GISTs treated in our Institute from 2008 to 2018. We have gathered data regarding clinical symptoms at the time of diagnosis, tumour site, type of surgery performed, tumour size, histopathological data and follow up data. RESULTS: We have analysed 950 cases of patients who underwent surgery for gastrointestinal neoplasia in our department from 2008 to 2018. We have found 12 cases affected by GIST and in 4 cases it was also a second tumour. In two cases GIST were incidentalomas and in the others two patients a second tumour was incidentally observed in primary GIST. CONCLUSION: Patients with GIST run the risk of developing a second neoplasm, nearly twice as high as the general population with a negative impact on survival; also, incidental GIST is often observed requiring a better molecular characterization for the high risk of developing second neoplasms with the aim of achieving an early diagnosis. KEY WORDS: Gist, Second neoplasm, Surgery.
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Neoplasias Gastrointestinales , Tumores del Estroma Gastrointestinal , Neoplasias Primarias Secundarias , Neoplasias Gastrointestinales/diagnóstico , Neoplasias Gastrointestinales/epidemiología , Neoplasias Gastrointestinales/cirugía , Tumores del Estroma Gastrointestinal/diagnóstico , Tumores del Estroma Gastrointestinal/epidemiología , Tumores del Estroma Gastrointestinal/cirugía , Humanos , Neoplasias Primarias Secundarias/epidemiología , Neoplasias Primarias Secundarias/cirugíaRESUMEN
Predicting the complete free energy landscape associated with protein-ligand unbinding may greatly help designing drugs with highly optimized pharmacokinetics. Here we investigate the unbinding of the iperoxo agonist to its target human neuroreceptor M2, embedded in a neuronal membrane. By feeding out-of-equilibrium molecular simulations data in a classification analysis, we identify the few essential reaction coordinates of the process. The full landscape is then reconstructed using an exact enhanced sampling method, well-tempered metadynamics in its funnel variant. The calculations reproduce well the measured affinity, provide a rationale for mutagenesis data, and show that the ligand can escape via two different routes. The allosteric modulator LY2119620 turns out to hamper both escapes routes, thus slowing down the unbinding process, as experimentally observed. This computationally affordable protocol is totally general, and it can be easily applied to determine the full free energy landscape of membrane receptors/drug interactions.
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Isoxazoles/farmacología , Simulación de Dinámica Molecular , Compuestos de Amonio Cuaternario/farmacología , Receptor Muscarínico M2/agonistas , Termodinámica , Humanos , Isoxazoles/química , Ligandos , Compuestos de Amonio Cuaternario/química , Receptor Muscarínico M2/químicaRESUMEN
The RNA recognition motif (RRM) is the most common RNA binding domain across eukaryotic proteins. It is therefore of great value to engineer its specificity to target RNAs of arbitrary sequence. This was recently achieved for the RRM in Rbfox protein, where four mutations R118D, E147R, N151S, and E152T were designed to target the precursor to the oncogenic miRNA 21. Here, we used a variety of molecular dynamics-based approaches to predict specific interactions at the binding interface. Overall, we have run approximately 50 microseconds of enhanced sampling and plain molecular dynamics simulations on the engineered complex as well as on the wild-type Rbfox·pre-miRNA 20b from which the mutated systems were designed. Comparison with the available NMR data on the wild type molecules (protein, RNA, and their complex) served to establish the accuracy of the calculations. Free energy calculations suggest that further improvements in affinity and selectivity are achieved by the S151T replacement.
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Motivo de Reconocimiento de ARN , Proteínas de Unión al ARN/química , ARN/química , Secuencia de Aminoácidos , Sitios de Unión/genética , Biología Computacional , Humanos , MicroARNs/química , MicroARNs/genética , MicroARNs/metabolismo , Modelos Moleculares , Simulación de Dinámica Molecular , Resonancia Magnética Nuclear Biomolecular , Conformación de Ácido Nucleico , Unión Proteica , Ingeniería de Proteínas , ARN/metabolismo , Motivo de Reconocimiento de ARN/genética , Estabilidad del ARN , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismoRESUMEN
Expanded CAG trinucleotide repeats in Huntington's disease (HD) are causative for neurotoxicity. The mutant CAG repeat RNA encodes neurotoxic polyglutamine proteins and can lead to a toxic gain of function by aberrantly recruiting RNA-binding proteins. One of these is the MID1 protein, which induces aberrant Huntingtin (HTT) protein translation upon binding. Here we have identified a set of CAG repeat binder candidates by in silico methods. One of those, furamidine, reduces the level of binding of HTT mRNA to MID1 and other target proteins in vitro. Metadynamics calculations, fairly consistent with experimental data measured here, provide hints about the binding mode of the ligand. Importantly, furamidine also decreases the protein level of HTT in a HD cell line model. This shows that small molecules masking RNA-MID1 interactions may be active against mutant HTT protein in living cells.
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Proteína Huntingtina/metabolismo , Enfermedad de Huntington/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Expansión de Repetición de Trinucleótido/efectos de los fármacos , Línea Celular/efectos de los fármacos , Humanos , Proteína Huntingtina/genética , Enfermedad de Huntington/tratamiento farmacológico , Proteínas del Tejido Nervioso/genética , Proteínas Nucleares/efectos de los fármacos , Proteínas Nucleares/metabolismo , Péptidos/farmacología , ARN Mensajero/metabolismo , Expansión de Repetición de Trinucleótido/genéticaRESUMEN
BACKGROUND: TAS-102 improves overall survival (OS) in patients with metastatic colorectal cancer (mCRC) refractory to standard treatments. However, predictive biomarkers of efficacy are currently lacking. PATIENTS AND METHODS: We treated a cohort of 43 chemorefractory mCRC patients treated with TAS-102, in a single institution expanded access, compassionate use programme. We stratified patients in two groups according to number of cycles received (<6 cycles and ≥6 cycles). OS, progression-free survival (PFS) and safety were evaluated. RESULTS: Thirteen out of 43 patients (30%) obtained a clinically relevant disease control with TAS-102 therapy. Eleven of them were treated for ≥6 cycles with TAS-102, reaching a median PFS of 7.5 months (95% CI 5.8 to 9.2 months) and a median OS of 11.2 months (95% CI range not reached yet). A trend towards significance (p=0.08) between a good performance status and response to TAS-102 was observed. Further, 7 out of the 11 TAS-102 long-treated patients achieved a clinical benefit from a previous treatment with regorafenib. A significant correlation between regorafenib and TAS-102 clinical efficacy was observed (p=0.008). Six out 13 regorafenib-naïve patients were treated with regorafenib after progression from TAS-102. All these patients achieved SD with a median duration of treatment with regorafenib of 6.1 months (range, 1.6-6.7). CONCLUSION: Patients with mCRC in good clinical conditions, even though having been heavily pretreated with all the available treatment options, could obtain a significant clinical benefit from treatment with TAS-102. Moreover, a previous clinical benefit obtained with regorafenib is potentially predictive of clinical efficacy of subsequent TAS-102 treatment.
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Targeted human cytolytic fusion proteins (hCFPs) are humanized immunotoxins for selective treatment of different diseases including cancer. They are composed of a ligand specifically binding to target cells genetically linked to a human apoptosis-inducing enzyme. hCFPs target cancer cells via an antibody or derivative (scFv) specifically binding to e.g., tumor associated antigens (TAAs). After internalization and translocation of the enzyme from endocytosed endosomes, the human enzymes introduced into the cytosol are efficiently inducing apoptosis. Under in vivo conditions such enzymes are subject to tight regulation by native inhibitors in order to prevent inappropriate induction of cell death in healthy cells. Tumor cells are known to upregulate these inhibitors as a survival mechanism resulting in escape of malignant cells from elimination by immune effector cells. Cytosolic inhibitors of Granzyme B and Angiogenin (Serpin P9 and RNH1, respectively), reduce the efficacy of hCFPs with these enzymes as effector domains, requiring detrimentally high doses in order to saturate inhibitor binding and rescue cytolytic activity. Variants of Granzyme B and Angiogenin might feature reduced affinity for their respective inhibitors, while retaining or even enhancing their catalytic activity. A powerful tool to design hCFPs mutants with improved potency is given by in silico methods. These include molecular dynamics (MD) simulations and enhanced sampling methods (ESM). MD and ESM allow predicting the enzyme-protein inhibitor binding stability and the associated conformational changes, provided that structural information is available. Such "high-resolution" detailed description enables the elucidation of interaction domains and the identification of sites where particular point mutations may modify those interactions. This review discusses recent advances in the use of MD and ESM for hCFP development from the viewpoints of scientists involved in both fields.
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Huntington's disease is a fatal and devastating neurodegenerative genetic disorder for which there is currently no cure. It is characterized by Huntingtin protein's mRNA transcripts with 36 or more CAG repeats. Inhibiting the formation of pathological complexes between these expanded transcripts and target proteins may be a valuable strategy against the disease. Yet, the rational design of molecules specifically targeting the expanded CAG repeats is limited by the lack of structural information. Here, we use well-tempered metadynamics-based free energy calculations to investigate pose and affinity of two ligands targeting CAG repeats for which affinities have been previously measured. The first consists of two 4-guanidinophenyl rings linked by an ester group. It is the most potent ligand identified so far, with Kd = 60(30) nM. The second consists of a 4-phenyl dihydroimidazole and 4-1H-indole dihydroimidazole connected by a C-C bond (Kd = 700(80) nM). Our calculations reproduce the experimental affinities and uncover the recognition pattern between ligands' and their RNA target. They also provide a molecular basis for the markedly different affinity of the two ligands for CAG repeats as observed experimentally. These findings may pave the way for a structure-based hit-to-lead optimization to further improve ligand selectivity toward CAG repeat-containing mRNAs.
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Enfermedad de Huntington/tratamiento farmacológico , Enfermedad de Huntington/genética , Imidazoles/química , Imidazoles/farmacología , ARN Mensajero/química , ARN Mensajero/genética , Repeticiones de Trinucleótidos/genética , Humanos , Ligandos , Simulación de Dinámica Molecular , Estructura Molecular , TermodinámicaRESUMEN
Sunitinib is a multi-targeted tyrosine kinase inhibitor widely used in clear cell renal carcinoma and in imatinib-resistant gastrointestinal stromal tumors. Sunitinib-associated cardiotoxicity has been recognized and includes hypertension, left ventricular dysfunction and congestive heart failure; nevertheless, few data exist in the literature regarding the role of preeclampsia-related angiogenic factors in sunitinib cardiotoxicity. We report a case of sunitinib-induced severe left ventricular dysfunction that occurred in a hypertensive woman with metastatic renal carcinoma and a history of preeclampsia, and a case of sunitinib-induced preeclampsia-like syndrome in a normotensive patient with an imatinib-resistant gastrointestinal stromal tumor. Our experience confirms that inhibition of angiogenic factors to treat cancer is a novel challenge for the oncologist and requires the cardiologist's support.
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Inductores de la Angiogénesis/metabolismo , Inhibidores de la Angiogénesis/efectos adversos , Antineoplásicos/efectos adversos , Indoles/efectos adversos , Preeclampsia/inducido químicamente , Preeclampsia/metabolismo , Pirroles/efectos adversos , Disfunción Ventricular Izquierda/inducido químicamente , Adulto , Inhibidores de la Angiogénesis/administración & dosificación , Inhibidores de la Angiogénesis/uso terapéutico , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Resultado Fatal , Femenino , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Humanos , Indoles/administración & dosificación , Indoles/uso terapéutico , Persona de Mediana Edad , Preeclampsia/diagnóstico , Preeclampsia/tratamiento farmacológico , Embarazo , Pirroles/administración & dosificación , Pirroles/uso terapéutico , Sunitinib , Disfunción Ventricular Izquierda/diagnóstico , Disfunción Ventricular Izquierda/tratamiento farmacológicoRESUMEN
PURPOSE: To investigate oxaliplatin combined with fluorouracil-based chemoradiotherapy as preoperative treatment for locally advanced rectal cancer. PATIENTS AND METHODS: Seven hundred forty-seven patients with resectable, locally advanced (cT3-4 and/or cN1-2) adenocarcinoma of the mid-low rectum were randomly assigned to receive pelvic radiation (50.4 Gy in 28 daily fractions) and concomitant infused fluorouracil (225 mg/m(2)/d) either alone (arm A, n = 379) or combined with oxaliplatin (60 mg/m(2) weekly × 6; arm B, n = 368). Overall survival is the primary end point. A protocol-planned analysis of response to preoperative treatment is reported here. RESULTS: Grade 3 to 4 adverse events during preoperative treatment were more frequent with oxaliplatin plus fluorouracil and radiation than with radiation and fluorouracil alone (24% v 8% of treated patients; P < .001). In arm B, 83% of the patients treated with oxaliplatin had five or more weekly administrations. Ninety-one percent, compared with 97% in the control arm, received ≥ 45 Gy (P < .001). Ninety-six percent versus 95% of patients underwent surgery with similar rates of abdominoperineal resections (20% v 18%, arm A v arm B). The rate of pathologic complete responses was 16% in both arms (odds ratio = 0.98; 95% CI, 0.66 to 1.44; P = .904). Twenty-six percent versus 29% of patients had pathologically positive lymph nodes (arm A v arm B; P = .447), 46% versus 44% had tumor infiltration beyond the muscularis propria (P = .701), and 7% versus 4% had positive circumferential resection margins (P = .239). Intra-abdominal metastases were found at surgery in 2.9% versus 0.5% of patients (arm A v arm B; P = .014). CONCLUSION: Adding oxaliplatin to fluorouracil-based preoperative chemoradiotherapy significantly increases toxicity without affecting primary tumor response. Longer follow-up is needed to assess the impact on efficacy end points.
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Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/radioterapia , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Fraccionamiento de la Dosis de Radiación , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Humanos , Italia , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Terapia Neoadyuvante , Compuestos Organoplatinos/administración & dosificación , Compuestos Organoplatinos/efectos adversos , Oxaliplatino , Neoplasias del Recto/patología , Neoplasias del Recto/cirugía , Análisis de SupervivenciaRESUMEN
BACKGROUND: Docetaxel (DTX) and zoledronic acid (ZOL) are effective in patients with hormone resistant prostate cancer (HRPC) with bone metastases. A phase I clinical trial of metronomic administration of Zoledronic Acid AN d TaxoterE combination (ZANTE trial) in 2 different sequences was conducted in HRPC. RESULTS: The maximum tolerated dose was not achieved with sequence A. Two patients at third level of sequence B developed dose limiting toxicity. A disease control was obtained in six out of nine patients treated with sequence A, where a decrease of biological markers and PSA were also observed. No evidence of anti-tumor activity was observed in patients treated with sequence B. PATIENTS AND METHODS: Twenty-two patients enrolled into the study (median age: 73 years; range: 43-80) received one of three escalated doses of DTX (30, 40 and 50 mg/m(2)) in combination with a fixed dose of ZOL (2 mg), both administered every 14 days in two different sequences: DTX at the day 1 followed by ZOL at the day 2 (sequence A) or the reverse (sequence B). Patients were evaluated for adverse events and serum IL-8, MMP-2 and MMP-9 were evaluated prior and after therapy with the two sequences of administration of DTX and ZOL. CONCLUSIONS: The bi-weekly combination of DTX (50 mg/m(2)) followed by ZOL was feasible and show promising anti-tumor activity.