Análisis retrospectivo de supervivencia y toxicidad en pacientes con adenocarcinoma gástrico avanzado tratados con el esquema DCF: Experiencia de un centro

Analizamos retrospectivamente una serie de 52 pacientes con adenocarcinoma gástrico avanzado y tratados con el esquema DCF (docetaxel, cisplatino, 5-¬‐fluorouracilo) entre los años 2005 y 2011. La mediana de supervivencia ha sido de 6’53 meses y el tiempo hasta la progresión de 4’33 meses. Como factores pronósticos independientes hemos obtenido el Performance Status basal (PS) y el sexo. Los pacientes con un PS2‐3 presentan un riesgo de muerte de 2’68 veces mayor respecto al PS0-1, con una mediana de supervivencia de 4’33 meses, frente a la de 9’73 meses de los pacientes con un PS0-1. El esquema DCF en carcinoma gástrico avanzado debe reservarse para los pacientes con un buen estado general basal.

Different fatty acid metabolism effects of (−)-epigallocatechin-3-gallate and C75 in adenocarcinoma lung cancer

Background Fatty acid synthase (FASN) is overexpressed and hyperactivated in several human carcinomas, including lung cancer. We characterize and compare the anti-cancer effects of the FASN inhibitors C75 and (−)-epigallocatechin-3-gallate (EGCG) in a lung cancer model. Methods We evaluated in vitro the effects of C75 and EGCG on fatty acid metabolism (FASN and CPT enzymes), cellular proliferation, apoptosis and cell signaling (EGFR, ERK1/2, AKT and mTOR) in human A549 lung carcinoma cells. In vivo, we evaluated their anti-tumour activity and their effect on body weight in a mice model of human adenocarcinoma xenograft. Results C75 and EGCG had comparable effects in blocking FASN activity (96,9% and 89,3% of inhibition, respectively). In contrast, EGCG had either no significant effect in CPT activity, the rate-limiting enzyme of fatty acid β-oxidation, while C75 stimulated CPT up to 130%. Treating lung cancer cells with EGCG or C75 induced apoptosis and affected EGFR-signaling. While EGCG abolished p-EGFR, p-AKT, p-ERK1/2 and p-mTOR, C75 was less active in decreasing the levels of EGFR and p-AKT. In vivo, EGCG and C75 blocked the growth of lung cancer xenografts but C75 treatment, not EGCG, caused a marked animal weight loss. Conclusions In lung cancer, inhibition of FASN using EGCG can be achieved without parallel stimulation of fatty acid oxidation and this effect is related mainly to EGFR signaling pathway. EGCG reduce the growth of adenocarcinoma human lung cancer xenografts without inducing body weight loss. Taken together, EGCG may be a candidate for future pre-clinical development.

Manejo del carcinoma de páncreas avanzado con el doblete de gemcitabina y erlotinib: Experiencia del Hospital Universitario La Fe

El tratamiento del carcinoma de páncreas continúa siendo uno de los grandes retos de la Oncología Médica. Un mejor conocimiento de las vías moleculares que intervienen en su desarrollo ha contribuido al uso de nuevos agentes terapéuticos dirigidos frente a las mismas. Una de esas vías es la del EGFR. Moore et al llevaron a cabo en 2007 un ensayo fase III aleatorizado en el que compararon gemcitabina frente a gemcitabina y erlotinib (un inhibidor de EGFR) y en el que demostraron de forma estadísticamente significativa por primera vez una mejoría en supervivencia global al asociar un agente a la gemcitabina en el tratamiento del adenocarcinoma pancreático avanzado. Hemos adoptado el esquema empleado en el ensayo fase III de Moore como primera línea de tratamiento del carcinoma pancreático localmente avanzado e irresecable y metastático en nuestro centro y creo necesario analizar la toxicidad y la supervivencia observada en nuestro medio. Para ello presento los resultados de eficacia, toxicidad y supervivencia global en la serie de 55 pacientes tratados con dicho esquema entre octubre de 2007 y octubre de 2010 en nuestro centro.

Estudi del paper de la JMJD3 en la progressió tumoral induïda per TGFB

La demetilasa d’histones JMJD3 (Jumonji domain containing protein 3), és un enzim capaç de de demetilar específicament la lisina 27 a la histona 3 (H3K27), eliminant així una marca epigenètica relacionada amb la repressió transcripcional. Recentment s’ha descrit que està implicada en el manteniment de la pluripotència de les cèl•lules mare embrionàries (ESCs). A més, també s’ha demostrat el seu paper en la regulació de processos fisiològics d’inflamació, de reprogramació epigenètica i de diferenciació, així com en la progressió del càncer de colon. En aquesta línia, resultats previs del grup han demostrat que l’expressió de JMJD3 està regulada per TGFB, en línies cel•lulars derivades de glioma. Tenint en compte aquests antecedents, l’objectiu principal d’aquest projecte ha estat estudiar el paper principal de la JMJD3 en la regulació epigenètica de la progressió tumoral induïda per TGFB. Els nostres resultats demostren que l’expressió de JMD3 en cèl•lules A549, derivades d’un adenocarcinoma de pulmó, es veu fortament induïda després d’un tractament amb TGFB. Aquest augment es produeix ràpidament i es manté almenys 48 hores, temps en el que té lloc la transició epitelio-mesenquimal (EMT). Per tal d’estudiar el paper de la JMD3 en aquest procés de transdiferenciació, vam generar línies cel•lulars estables mitjançant la infecció amb vectors lentivirals que expressaven shRNAs específics contra la seva seqüència. El knockdown de JMJD3 va bloquejar significativament l’expressió de marcadors mesenquimals, tant a nivell RNA com de proteïna en presència de TGFB. Aquests resultats suggereixen que la demetilasa d’histones JMJD3 té un paper clau en la regulació de la EMT induïda per TGFB.

Characterization of human pancreatic orthotopic tumor xenografts suitable for drug screening

Background Efforts to identify novel therapeutic options for human pancreatic ductal adenocarcinoma (PDAC) have failed to result in a clear improvement in patient survival to date. Pancreatic cancer requires efficient therapies that must be designed and assayed in preclinical models with improved predictor ability. Among the available preclinical models, the orthotopic approach fits with this expectation, but its use is still occasional. Methods An in vivo platform of 11 orthotopic tumor xenografts has been generated by direct implantation of fresh surgical material. In addition, a frozen tumorgraft bank has been created, ensuring future model recovery and tumor tissue availability. Results Tissue microarray studies allow showing a high degree of original histology preservation and maintenance of protein expression patterns through passages. The models display stable growth kinetics and characteristic metastatic behavior. Moreover, the molecular diversity may facilitate the identification of tumor subtypes and comparison of drug responses that complement or confirm information obtained with other preclinical models. Conclusions This panel represents a useful preclinical tool for testing new agents and treatment protocols and for further exploration of the biological basis of drug responses.

Characterization of human pancreatic orthotopic tumor xenografts suitable for drug screening

Background Efforts to identify novel therapeutic options for human pancreatic ductal adenocarcinoma (PDAC) have failed to result in a clear improvement in patient survival to date. Pancreatic cancer requires efficient therapies that must be designed and assayed in preclinical models with improved predictor ability. Among the available preclinical models, the orthotopic approach fits with this expectation, but its use is still occasional. Methods An in vivo platform of 11 orthotopic tumor xenografts has been generated by direct implantation of fresh surgical material. In addition, a frozen tumorgraft bank has been created, ensuring future model recovery and tumor tissue availability. Results Tissue microarray studies allow showing a high degree of original histology preservation and maintenance of protein expression patterns through passages. The models display stable growth kinetics and characteristic metastatic behavior. Moreover, the molecular diversity may facilitate the identification of tumor subtypes and comparison of drug responses that complement or confirm information obtained with other preclinical models. Conclusions This panel represents a useful preclinical tool for testing new agents and treatment protocols and for further exploration of the biological basis of drug responses.

Minor salivary gland tumors: a clinicopathological study of 18 cases

Introduction: Minor salivary gland tumors (MSGTs) are infrequent, representing 10-15% of all salivary neoplasms. Despite this low frequency, MSGTs conform a heterogeneous group of neoplasms characterized by a broad range of histological types. Patients and method: We identified cases of MSGT in a retrospective study of the biopsies made in the period 1997-2007 in the Service of Oral Surgery (Dental Clinic of the University of Barcelona, Spain). The data collected comprised patient age and sex, the clinical characteristics and location of the tumor, the duration of the lesion, its size, the treatment provided, and the histopathological findings. Results: Of the 18 cases of MSGT studied, 12 corresponded to women (66.7%) and 6 to men (33.3%). The great majority (94.4%) were benign tumors. The preferential location was the posterior third of the hard palate (33.2%), followed by the soft palate (16.7%) and the mucosa of the upper lip (16.7%). The histopathological diagnoses of our MSGTs comprised 10 pleomorphic adenomas (55.3%), 2 cystadenomas (11.1%), 1 myoepithelioma (5.6%), 1 sialadenoma papilliferum (5.6%), 1 basal cell adenoma (5.6%), 1 Warthin"s tumor (5.6%), 1 canalicular adenoma (5.6%), and 1 low-grade polymorphic adenocarcinoma (5.6%). Discussion and conclusions: Coinciding with our own results, the literature describes a high recurrence rate for MSGTs (5-30%) when surgical removal is incomplete. Six percent of all benign minor salivary gland tumors are considered to relapse, versus 65% of all malignant lesions. Periodic clinical controls are required, since the possibility of malignant transformation must be taken into account

Kinesin-5/Eg5 is important for transport of CARTS from the trans-Golgi network to the cell surface

Here we report that the kinesin-5 motor Klp61F, which is known for its role in bipolar spindle formation in mitosis, is required for protein transport from the Golgi complex to the cell surface in Drosophila S2 cells. Disrupting the function of its mammalian orthologue, Eg5, in HeLa cells inhibited secretion of a protein called pancreatic adenocarcinoma up-regulated factor (PAUF) but, surprisingly, not the trafficking of vesicular stomatitis virus G protein (VSV-G) to the cell surface. We have previously reported that PAUF is transported from the trans-Golgi network (TGN) to the cell surface in specific carriers called CARTS that exclude VSV-G. Inhibition of Eg5 function did not affect the biogenesis of CARTS; however, their migration was delayed and they accumulated near the Golgi complex. Altogether, our findings reveal a surprising new role of Eg5 in nonmitotic cells in the facilitation of the transport of specific carriers, CARTS, from the TGN to the cell surface.

Characterization of human pancreatic orthotopic tumor xenografts suitable for drug screening

Background Efforts to identify novel therapeutic options for human pancreatic ductal adenocarcinoma (PDAC) have failed to result in a clear improvement in patient survival to date. Pancreatic cancer requires efficient therapies that must be designed and assayed in preclinical models with improved predictor ability. Among the available preclinical models, the orthotopic approach fits with this expectation, but its use is still occasional. Methods An in vivo platform of 11 orthotopic tumor xenografts has been generated by direct implantation of fresh surgical material. In addition, a frozen tumorgraft bank has been created, ensuring future model recovery and tumor tissue availability. Results Tissue microarray studies allow showing a high degree of original histology preservation and maintenance of protein expression patterns through passages. The models display stable growth kinetics and characteristic metastatic behavior. Moreover, the molecular diversity may facilitate the identification of tumor subtypes and comparison of drug responses that complement or confirm information obtained with other preclinical models. Conclusions This panel represents a useful preclinical tool for testing new agents and treatment protocols and for further exploration of the biological basis of drug responses.

Characterization of human pancreatic orthotopic tumor xenografts suitable for drug screening

Background Efforts to identify novel therapeutic options for human pancreatic ductal adenocarcinoma (PDAC) have failed to result in a clear improvement in patient survival to date. Pancreatic cancer requires efficient therapies that must be designed and assayed in preclinical models with improved predictor ability. Among the available preclinical models, the orthotopic approach fits with this expectation, but its use is still occasional. Methods An in vivo platform of 11 orthotopic tumor xenografts has been generated by direct implantation of fresh surgical material. In addition, a frozen tumorgraft bank has been created, ensuring future model recovery and tumor tissue availability. Results Tissue microarray studies allow showing a high degree of original histology preservation and maintenance of protein expression patterns through passages. The models display stable growth kinetics and characteristic metastatic behavior. Moreover, the molecular diversity may facilitate the identification of tumor subtypes and comparison of drug responses that complement or confirm information obtained with other preclinical models. Conclusions This panel represents a useful preclinical tool for testing new agents and treatment protocols and for further exploration of the biological basis of drug responses.

Aquaporin 3 (AQP3) participates in the cytotoxic response to nucleoside-derived drugs

Background: Nucleoside analogs used in the chemotherapy of solid tumors, such as the capecitabine catabolite50-deoxy-5-fluorouridine (50-DFUR) trigger a transcriptomic response that involves the aquaglyceroporin aquaporin 3 along with other p53-dependent genes. Here, we examined whether up-regulation of aquaporin 3 (AQP3) mRNA incancer cells treated with 50-DFUR represents a collateral transcriptomic effect of the drug, or conversely, AQP3participates in the activity of genotoxic agents. Methods: The role of AQP3 in cell volume increase, cytotoxicity and cell cycle arrest was analyzed using loss-of-function approaches. Results: 50-DFUR and gemcitabine, but not cisplatin, stimulated AQP3 expression and cell volume, which was partially and significantly blocked by knockdown of AQP3. Moreover, AQP3 siRNA significantly blocked other effects of nucleoside analogs, including G1/S cell cycle arrest, p21 and FAS up-regulation, and cell growth inhibition. Short incubations with 5-fluorouracil (5-FU) also induced AQP3 expression and increased cell volume, and the inhibition of AQP3 expression significantly blocked growth inhibition triggered by this drug. To further establish whether AQP3 induction is related to cell cycle arrest and apoptosis, cells were exposed to long incubations with escalating doses of 5-FU. AQP3 was highly up-regulated at doses associated with cell cycle arrest, whereas at doses promoting apoptosis induction of AQP3 mRNA expression was reduced. Conclusions: Based on the results, we propose that the aquaglyceroporin AQP3 is required for cytotoxic activity of 5’-DFUR and gemcitabine in the breast cancer cell line MCF7 and the colon adenocarcinoma cell line HT29, and is implicated in cell volume increase and cell cycle arrest.

Aquaporin 3 (AQP3) participates in the cytotoxic response to nucleoside-derived drugs

Background: Nucleoside analogs used in the chemotherapy of solid tumors, such as the capecitabine catabolite50-deoxy-5-fluorouridine (50-DFUR) trigger a transcriptomic response that involves the aquaglyceroporin aquaporin 3 along with other p53-dependent genes. Here, we examined whether up-regulation of aquaporin 3 (AQP3) mRNA incancer cells treated with 50-DFUR represents a collateral transcriptomic effect of the drug, or conversely, AQP3participates in the activity of genotoxic agents. Methods: The role of AQP3 in cell volume increase, cytotoxicity and cell cycle arrest was analyzed using loss-of-function approaches. Results: 50-DFUR and gemcitabine, but not cisplatin, stimulated AQP3 expression and cell volume, which was partially and significantly blocked by knockdown of AQP3. Moreover, AQP3 siRNA significantly blocked other effects of nucleoside analogs, including G1/S cell cycle arrest, p21 and FAS up-regulation, and cell growth inhibition. Short incubations with 5-fluorouracil (5-FU) also induced AQP3 expression and increased cell volume, and the inhibition of AQP3 expression significantly blocked growth inhibition triggered by this drug. To further establish whether AQP3 induction is related to cell cycle arrest and apoptosis, cells were exposed to long incubations with escalating doses of 5-FU. AQP3 was highly up-regulated at doses associated with cell cycle arrest, whereas at doses promoting apoptosis induction of AQP3 mRNA expression was reduced. Conclusions: Based on the results, we propose that the aquaglyceroporin AQP3 is required for cytotoxic activity of 5’-DFUR and gemcitabine in the breast cancer cell line MCF7 and the colon adenocarcinoma cell line HT29, and is implicated in cell volume increase and cell cycle arrest.

Cyclin-dependent kinases 4 and 6 control tumor progression and direct glucose oxidation in the pentose cycle

Cyclin-dependent kinases CDK4 and CDK6 are essential for the control of the cell cycle through the G1 phase. Aberrant expression of CDK4 and CDK6 is a hall- mark of cancer, which would suggest that CDK4 and CDK6 are attractive targets for cancer therapy. Herein, we report that calcein AM is a potent specific inhibitor of CDK4 and CDK6 in HCT116 human colon adenocarcinoma cells, inhibiting retinoblastoma protein (pRb) phosphorylation and inducing cell cycle arrest in the G1 phase. The metabolic effects of calcein AM (the calcein acetoxymethyl-ester) on HCT116 cells were also evaluated and the flux between the oxidative and non-oxidative branches of the pentose phos-phate pathway was significantly altered. To elucidate whe-ther these metabolic changes were due to the inhibition of CDK4 and CDK6, we also characterized the metabolic profile of a CDK4, CDK6 and CDK2 triple knockout of mouse embryonic fibroblasts. The results show that the metabolic profile associated with the depletion of CDK4, CDK6 and CDK2 coincides with the metabolic changes induced by calcein AM on HCT116 cells, thus confirming that the inhibition of CDK4 and CDK6 disrupts the balance between the oxidative and non-oxidative branches of the pentose phosphate pathway. Taken together, these results indicate that low doses of calcein can halt cell division and kill tumor cells. Thus, selective inhibition of CDK4 and CDK6 may be of greater pharmacological interest, since inhibitors of these kinases affect both cell cycle progression and the robust metabolic profile of tumors.

Pancreatic Cancer Cell Glycosylation Regulates Cell Adhesion and Invasion through the Modulation of a2b1 Integrin and E-Cadherin Function

In our previous studies we have described that ST3Gal III transfected pancreatic adenocarcinoma Capan-1 and MDAPanc-28 cells show increased membrane expression levels of sialyl-Lewis x (SLex) along with a concomitant decrease in α2,6-sialic acid compared to control cells. Here we have addressed the role of this glycosylation pattern in the functional properties of two glycoproteins involved in the processes of cancer cell invasion and migration, α2β1 integrin, the main receptor for type 1 collagen, and E-cadherin, responsible for cell-cell contacts and whose deregulation determines cell invasive capabilities. Our results demonstrate that ST3Gal III transfectants showed reduced cell-cell aggregation and increased invasive capacities. ST3Gal III transfected Capan-1 cells exhibited higher SLex and lower α2,6-sialic acid content on the glycans of their α2β1 integrin molecules. As a consequence, higher phosphorylation of focal adhesion kinase tyrosine 397, which is recognized as one of the first steps of integrin-derived signaling pathways, was observed in these cells upon adhesion to type 1 collagen. This molecular mechanism underlies the increased migration through collagen of these cells. In addition, the pancreatic adenocarcinoma cell lines as well as human pancreatic tumor tissues showed colocalization of SLex and E-cadherin, which was higher in the ST3Gal III transfectants. In conclusion, changes in the sialylation pattern of α2β1 integrin and E-cadherin appear to influence the functional role of these two glycoproteins supporting the role of these glycans as an underlying mechanism regulating pancreatic cancer cell adhesion and invasion