The miR-17-92 cluster counteracts quiescence and chemoresistance of pancreatic cancer stem cells

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 18-06-2014Pancreatic ductal adenocarcinoma is the fourth most frequent cause for cancer-related deaths due to late diagnosis and limited response to chemotherapy. As one of the identified drug resistance mechanism, a distinct subpopulation of cancer stem cells (CSCs) has not only been shown to promote tumor progression and metastasis, but has also been implicated in tumor relapse based on intrinsic drug-resistance. Therefore, advancing our understanding on the mechanism of drug resistance in CSCs versus non-CSCs could lead to more effective therapeutic strategies. Since CSCs and non-CSCs share an identical genetic background, we studied the epigenetic regulation of CSCs as the defining regulatory machinery of CSCs. Using high-throughput miRNA expression analysis; we identified a panel of common miRNAs to be consistently underrepresented in Gemcitabine-treated tumors compared to untreated tumors. Subsequent gain-of-function and loss-of-function experiments demonstrated that the miR-17-92 cluster encoding six related microRNAs as the most strikingly suppressed miRNA family in chemoresistant CSCs is of crucial relevance for CSC function. Specifically, lentivirus-mediated over-expression of the miR cluster in CSCs significantly reduced their self-renewal, in vivo tumorigenicity, and resistance to Gemcitabine by down-regulation of multiple key genes belonging to the Nodal/TGF-β1 signaling cascade such as ALK4, TGFBR2, SMAD2, SMAD4 as well as direct inhibition of Nodal/TGF-β1- responsive genes p21, p57 and TBX3. MiR-overexpression in CSCs also resulted in their enhanced proliferation, which eventually resulted in CSC exhaustion during serial transplantation via down-regulation of p21 and p57. Thus, our study identifies the miR-17- 92 cluster as an important family of miRNAs that play a crucial role in CSC biology including chemoresistance. Our findings indicate potential for developing modulators of this cluster to overcome drug resistance in pancreatic CSCs and eventually improve the miserable outcome of patients with pancreatic ductal adenocarcinomaEl adenocarcinoma pancreático es la cuarta causa principal de muerte relacionada con el cáncer debido a su diagnostico tardío y su mala respuesta a la quimioterapia. Uno de los posibles mecanismos de quimioresistencia que ha sido descrito se basa en la existencia de un subconjunto de células tumorales con propiedades troncales, denominadas células troncales de cáncer (CSC), las cuales impulsan el crecimiento del tumor de páncreas, metástasis y quimioresistencia. Por lo tanto, si podemos progresar en el conocimiento del mecanismo de resistencia a la quimioterapa en las células troncales de cáncer, probablemente nos ayudaría a desarrollar terapias más eficientes. Debido a que las células troncales de cáncer y las células cancerígenas comparten un perfil genético idéntico, hemos estudiado la regulación epigenética de las CSCs para definir el mecanismo de regulación. Utilizando el análisis de expresión de los genes de miRNA, hemos identificado un grupo de miRNAs comunes que de manera consistente se encontraban poco expresados en aquellos tumores que habían sido tratados con Gemcitabina comparándolo con los tumores sin tratar. Los experimentos posteriores de ganancia y perdida de funcionalidad, demostraron que el miR-17-92 cluster codificaba seis microRNAs que se encontraban suprimidos en las CSCs quimioresistentes, lo cual era de crucial relevancia en la funcionalidad de las CSCs. Por consiguiente, al sobrexpresar el miR cluster mediante el uso de un lentivirus en las CSCs, observamos que se reducía de manera significativa la capacidad de auto-replicación, tumorigenicidad in vivo y se reducía la resistencia a la Gemcitabina via inhibición de la expresión de genes clave que pertenecen a la vía de señalizaciónn de Nodal/ TGF-β1 como ALK4, TGFBR2, SMAD2, SMAD4, así como también otros genes que responden a la inhibición tales como p21, p57 y TBX3. La sobreexpresión de miR en las CSCs también resultó en un aumento de la proliferación, lo cual eventualmente resultó en una disminución de la capacidad de auto-replicació en pases seriados debido a la reducción de la expresión de los genes p21 y p57. En resumen, nuestro estudio identifica el miR-17-92 cluster como una familia de miRNAs muy importante que juega un rol crucial en la biología de las CSC incluida la quimioresistencia. Nuestros hallazgos muestran un fuerte potencial para el posible desarrollo de modulaodores de este cluster para poder suprimir la resistencia de las CSCs, y así finalmente, poder mejorar el pronóstico tan miserable de los pacientes con adenocarcinoma pancreático

The miR-17-92 cluster counteracts quiescence and chemoresistance of pancreatic cancer stem cells

Tesis doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 18-06-2014Pancreatic ductal adenocarcinoma is the fourth most frequent cause for cancer-related deaths due to late diagnosis and limited response to chemotherapy. As one of the identified drug resistance mechanism, a distinct subpopulation of cancer stem cells (CSCs) has not only been shown to promote tumor progression and metastasis, but has also been implicated in tumor relapse based on intrinsic drug-resistance. Therefore, advancing our understanding on the mechanism of drug resistance in CSCs versus non-CSCs could lead to more effective therapeutic strategies. Since CSCs and non-CSCs share an identical genetic background, we studied the epigenetic regulation of CSCs as the defining regulatory machinery of CSCs. Using high-throughput miRNA expression analysis; we identified a panel of common miRNAs to be consistently underrepresented in Gemcitabine-treated tumors compared to untreated tumors. Subsequent gain-of-function and loss-of-function experiments demonstrated that the miR-17-92 cluster encoding six related microRNAs as the most strikingly suppressed miRNA family in chemoresistant CSCs is of crucial relevance for CSC function. Specifically, lentivirus-mediated over-expression of the miR cluster in CSCs significantly reduced their self-renewal, in vivo tumorigenicity, and resistance to Gemcitabine by down-regulation of multiple key genes belonging to the Nodal/TGF-β1 signaling cascade such as ALK4, TGFBR2, SMAD2, SMAD4 as well as direct inhibition of Nodal/TGF-β1- responsive genes p21, p57 and TBX3. MiR-overexpression in CSCs also resulted in their enhanced proliferation, which eventually resulted in CSC exhaustion during serial transplantation via down-regulation of p21 and p57. Thus, our study identifies the miR-17- 92 cluster as an important family of miRNAs that play a crucial role in CSC biology including chemoresistance. Our findings indicate potential for developing modulators of this cluster to overcome drug resistance in pancreatic CSCs and eventually improve the miserable outcome of patients with pancreatic ductal adenocarcinomaEl adenocarcinoma pancreático es la cuarta causa principal de muerte relacionada con el cáncer debido a su diagnostico tardío y su mala respuesta a la quimioterapia. Uno de los posibles mecanismos de quimioresistencia que ha sido descrito se basa en la existencia de un subconjunto de células tumorales con propiedades troncales, denominadas células troncales de cáncer (CSC), las cuales impulsan el crecimiento del tumor de páncreas, metástasis y quimioresistencia. Por lo tanto, si podemos progresar en el conocimiento del mecanismo de resistencia a la quimioterapa en las células troncales de cáncer, probablemente nos ayudaría a desarrollar terapias más eficientes. Debido a que las células troncales de cáncer y las células cancerígenas comparten un perfil genético idéntico, hemos estudiado la regulación epigenética de las CSCs para definir el mecanismo de regulación. Utilizando el análisis de expresión de los genes de miRNA, hemos identificado un grupo de miRNAs comunes que de manera consistente se encontraban poco expresados en aquellos tumores que habían sido tratados con Gemcitabina comparándolo con los tumores sin tratar. Los experimentos posteriores de ganancia y perdida de funcionalidad, demostraron que el miR-17-92 cluster codificaba seis microRNAs que se encontraban suprimidos en las CSCs quimioresistentes, lo cual era de crucial relevancia en la funcionalidad de las CSCs. Por consiguiente, al sobrexpresar el miR cluster mediante el uso de un lentivirus en las CSCs, observamos que se reducía de manera significativa la capacidad de auto-replicación, tumorigenicidad in vivo y se reducía la resistencia a la Gemcitabina via inhibición de la expresión de genes clave que pertenecen a la vía de señalizaciónn de Nodal/ TGF-β1 como ALK4, TGFBR2, SMAD2, SMAD4, así como también otros genes que responden a la inhibición tales como p21, p57 y TBX3. La sobreexpresión de miR en las CSCs también resultó en un aumento de la proliferación, lo cual eventualmente resultó en una disminución de la capacidad de auto-replicació en pases seriados debido a la reducción de la expresión de los genes p21 y p57. En resumen, nuestro estudio identifica el miR-17-92 cluster como una familia de miRNAs muy importante que juega un rol crucial en la biología de las CSC incluida la quimioresistencia. Nuestros hallazgos muestran un fuerte potencial para el posible desarrollo de modulaodores de este cluster para poder suprimir la resistencia de las CSCs, y así finalmente, poder mejorar el pronóstico tan miserable de los pacientes con adenocarcinoma pancreático

Heavy-Vehicle Response to Crosswind: Evaluation of Driver Reactions Using a Dynamic Driving Simulator

Heavy vehicles exiting (or entering) a tunnel at high speed under a strong crosswind is a particularly critical condition since the aerodynamic load changes drastically, greatly affecting the lateral stability of the vehicle. Often, active control systems (active suspensions, active front steering, etc.) and infrastructure elements (e.g., wind fences) are proposed to reduce the induced risks. To help the design of these devices, the present paper investigates the response of the vehicle–driver system in the case of a high-sided lorry exiting a tunnel under crosswind, by using Driver-In-the-Loop simulations. The study was performed using the dynamic driving simulator of Politecnico di Milano and 28 test drivers. Vehicle and aerodynamic models have been developed to reproduce the phenomenon in a highly immersive environment. During the tests, several combinations of vehicle and wind speed were considered. The effect of vehicle loading condition (Empty and Laden) was also investigated. The performed tests allowed us to gain information about the sequence of the driver’s actions and associated delays, which may induce lane deviation or, in the worst case, rollover. It was found that lane invasion may happen for ratios of lateral aerodynamic force over vehicle weight force bigger than 0.1, while rollover could happen for ratios bigger than 0.3. Moreover, it was found that the driver’s response typically happens with a delay of ∼0.25 s with respect to the onset of the crosswind stimulus

The 'healthy side' of anosognosia for hemiplegia: Increased sense of agency for the unimpaired limb or motor compensation?

Anosognosic patients show a lack of awareness for their hemiplegia coupled with a distorted sense of agency for the actions performed by the plegic limbs. Since anosognosia is often associated with right brain damage, this hemisphere seems to play a dominant role in monitoring awareness for motor actions. Therefore, we would expect that anosognosic patients show distorted awareness and sense of agency also for actions performed with the unimpaired limb

[Organizational and financial aspects of the introduction of Botox® in the clinical diagnostic therapeutic process of chronic migraine at a Local Health Unit in Italy]

BACKGROUND: Existing literature shows that the use of Botox®/onabotulinumtoxinA (BT) in chronic migraine (CM) is promising from a cost-effectiveness standpoint and the use of a clinical diagnostic therapeutic process (CDTP) dedicated to CM allows a reduction of pathology costs. The inclusion of BT in chronic migraine therapy at a Roman ASL involves the need to investigate the real treatment costs of a CDTP and to measure how a targeted organizational CDTP strategy for CM allows insuring treatment accessibility, sustainability, and appropriateness.OBJECTIVE: To conduct a cost-effectiveness analysis of providing administration of BT in patients with CM using real world data from an ASL in Rome.METHODS: The real world cost data for approximately 215 anonymous patients were summarized. The cost data were extrapolated from the database of the ASL and they populated a Markov decision model developed by Allergan. The analysis is based on a decision model populated with real drug and service cost data, for the years 2010-2012. The financial assessment was conducted from the viewpoint of the Italian National Health Service.RESULTS: Over a 2 year temporal horizon, incremental BT costs, compared to a placebo, are equal to € 261 against an incremental gain of 0.0655 QALY in favor of BT. The ratio between costs and incremental QALY generates an ICER of 3,983 €/QALY, favorable and below the acceptability threshold used by many countries for reimbursement decisions (25,000-40,000 € per QALY gained).CONCLUSIONS: The inclusion of BT in the CDTP dedicated to CM of an Italian ASL improves both clinical outcomes of the patients and the allocation of the SSN available resources.[Article in Italian

Mast cells impair melanoma cell homing and metastasis by inhibiting HMGA1 secretion

Mast cells; Melanoma; MetastasisMastòcits; Melanoma; MetàstasiMastocitos; Melanoma; MetástasisMetastatic disease is the major cause of death from cancer. From the primary tumour, cells remotely prepare the environment of the future metastatic sites by secreted factors and extracellular vesicles. During this process, known as pre-metastatic niche formation, immune cells play a crucial role. Mast cells are haematopoietic bone marrow-derived innate immune cells whose function in lung immune response to invading tumours remains to be defined. We found reduced melanoma lung metastasis in mast cell-deficient mouse models (Wsh and MCTP5-Cre-RDTR), supporting a pro-metastatic role for mast cells in vivo. However, due to evidence pointing to their antitumorigenic role, we studied the impact of mast cells in melanoma cell function in vitro. Surprisingly, in vitro co-culture of bone-marrow-derived mast cells with melanoma cells showed that they have an intrinsic anti-metastatic activity. Mass spectrometry analysis of melanoma-mast cell co-cultures secretome showed that HMGA1 secretion by melanoma cells was significantly impaired. Consistently, HMGA1 knockdown in B16-F10 cells reduced their metastatic capacity in vivo. Importantly, analysis of HMGA1 expression in human melanoma tumours showed that metastatic tumours with high HMGA1 expression are associated with reduced overall and disease-free survival. Moreover, we show that HMGA1 is reduced in the nuclei and enriched in the cytoplasm of melanoma metastatic lesions when compared to primary tumours. These data suggest that high HMGA1 expression and secretion from melanoma cells promote metastatic behaviour. Targeting HMGA1 expression intrinsically or extrinsically by mast cells actions reduce melanoma metastasis. Our results pave the way to the use of HMGA1 as anti-metastatic target in melanoma as previously suggested in other cancer types.US NIH (R01-CA169416); Children's Cancer and Blood Foundation; Feldestein Foundation; Melanoma Research Alliance; Nancy C. and Daniel P. Paduano Foundation; Starr Foundation; Translational NeTwork for the CLinical application of Extracellular Vesicle

Solitary fibrous tumor of the pleura presenting with syncope episodes when coughing

<p>Abstract</p> <p>Background</p> <p>Solitary fibrous tumor of the pleura is a rarely encountered clinical entity which may have different clinical pictures. Although the majority of these neoplasms have a benign course, the malignant form has also been reported.</p> <p>Case presentation</p> <p>We herein describe a case of 72 year-old man with head, facial, and thoracic traumas caused by neurally-mediated situational syncope when coughing. The diagnostic work-up including chest x-ray, CT and PET, revealed a large solitary mass of the left hemithorax. Radical surgical resection of the mass was performed through a left lateral thoracotomy and completed with a wedge resection of the lingula. Hystological examination of the surgical specimen showed an encapsulated mass measuring 12 × 11.5 × 6 cm consistent with a solitary fibrous tumor of the pleura. It's surgical removal definitively resolved the neurologic manifestations. The patient had no postoperative complications. At two years follow-up the patient is free from recurrence and without clinical manifestations.</p> <p>Conclusion</p> <p>In our case its resection definitively resolved the episodes of situational syncope due, in our opinion, to the large thoracic mass compressing the phrenic nerve</p

Adiposity Predicts Cognitive Decline in Older Persons with Diabetes: A 2-Year Follow-Up

BACKGROUND: The mechanisms related to cognitive impairment in older persons with Type 2 diabetes (DM) remains unclear. We tested if adiposity parameters and body fat distribution could predict cognitive decline in older persons with DM vs. normal glucose tolerance (NGT). METHODOLOGY: 693 older persons with no dementia were enrolled: 253 with DM in good metabolic control; 440 with NGT (age range:65-85 years). Longitudinal study comparing DM and NGT individuals according to the association of baseline adiposity parameters (body mass index (BMI), waist-hip-ratio (WHR), waist circumference (WC) and total body fat mass) to cognitive change (Mini Mental State Examination (MMSE), a composite score of executive and attention functioning (CCS) over time. FINDINGS: At baseline, in DM participants, MMSE correlated with WHR (beta = -0.240; p = 0.043), WC (beta = -0.264; p = 0.041) while CCS correlated with WHR (beta = -0.238; p = 0.041), WC (beta = -0.326; p = 0.013) after adjusting for confounders. In NGT subjects, no significant correlations were found among any adiposity parameters and MMSE, while CCS was associated with WHR (beta = -0.194; p = 0.036) and WC (beta = -0.210; p = 0.024). Participants with DM in the 3(rd) tertile of total fat mass showed the greatest decline in cognitive performance compared to those in 1(st) tertile (tests for trend: MMSE(p = 0.007), CCS(p = 0.003)). Logistic regression models showed that 3(rd) vs. 1(st) tertile of total fat mass, WHR, and WC predicted an almost two-fold decline in cognitive function in DM subjects at 2(nd) yr (OR 1.68, 95%IC 1.08-3.52). CONCLUSIONS: Total fat mass and central adiposity predict an increased risk for cognitive decline in older person with DM