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// Chloe M. Falvey 1 , Tracey R. O’Donovan 1 , Shereen El-Mashed 1 , Michelle J. Nyhan 1 , Seamus O’Reilly 2 , Sharon L. McKenna 1 1 Cork Cancer Research Centre, University College Cork, Cork, Ireland 2 Department of Oncology, Cork University Hospital, Cork, Ireland Correspondence to: Sharon L. McKenna, email: s.mckenna@ucc.ie Keywords: esophageal, autophagy, apoptosis, ISG15, UBE2L6 Received: February 05, 2016 Accepted: January 16, 2017 Published: February 08, 2017 ABSTRACT Esophageal cancer remains a poor prognosis cancer due to advanced stage of presentation and drug resistant disease. To understand the molecular mechanisms influencing response to chemotherapy, we examined genes that are differentially expressed between drug sensitive, apoptosis competent esophageal cancer cells (OE21, OE33, FLO-1) and those which are more resistant and do not exhibit apoptosis (KYSE450 and OE19). Members of the ISG15 (ubiquitin-like) protein modification pathway, including UBE2L6 and ISG15, were found to be more highly expressed in the drug sensitive cell lines. In this study, we evaluated the contribution of these proteins to the response of drug sensitive cells. Depletion of UBE2L6 or ISG15 with siRNA did not influence caspase-3 activation or nuclear fragmentation following treatment with 5-fluorouracil (5-FU). We assessed autophagy by analysis of LC3II expression and Cyto-ID staining. Depletion of either ISG15 or UBE2L6 resulted in enhanced endogenous autophagic flux. An increase in autophagic flux was also observed following treatment with cytotoxic drugs (5-FU, rapamycin). In ISG15 depleted cells, this increase in autophagy was associated with improved recovery of drug treated cells. In contrast, UBE2L6 depleted cells, did not show enhanced recovery. UBE2L6 may therefore influence additional targets that limit the pro-survival effect of ISG15 depletion. These data identify UBE2L6 and ISG15 as novel inhibitors of autophagy, with the potential to influence chemosensitivity in esophageal cancer cells.

Esophageal cancer remains a poor prognosis cancer due to advanced stage of presentation and drug resistant disease. To understand the molecular mechanisms influencing response to chemotherapy, we examined genes that are differentially expressed between drug sensitive, apoptosis competent esophageal cancer cells (OE21, OE33, FLO-1) and those which are more resistant and do not exhibit apoptosis (KYSE450 and OE19). Members of the ISG15 (ubiquitin-like) protein modification pathway, including UBE2L6 and ISG15, were found to be more highly expressed in the drug sensitive cell lines. In this study, we evaluated the contribution of these proteins to the response of drug sensitive cells. Depletion of UBE2L6 or ISG15 with siRNA did not influence caspase-3 activation or nuclear fragmentation following treatment with 5-fluorouracil (5-FU). We assessed autophagy by analysis of LC3II expression and Cyto-ID staining. Depletion of either ISG15 or UBE2L6 resulted in enhanced endogenous autophagic flux. An increase in autophagic flux was also observed following treatment with cytotoxic drugs (5-FU, rapamycin). In ISG15 depleted cells, this increase in autophagy was associated with improved recovery of drug treated cells. In contrast, UBE2L6 depleted cells, did not show enhanced recovery. UBE2L6 may therefore influence additional targets that limit the pro-survival effect of ISG15 depletion. These data identify UBE2L6 and ISG15 as novel inhibitors of autophagy, with the potential to influence chemosensitivity in esophageal cancer cells.

International audience; The use of Synthetic Aperture Radar interferometry (InSAR) in northern Chile, one of the most seismically active regions in the world, is of great importance. InSAR enables geodesists not only to accurately measure Earth's motions but also to improve fault slip map resolution and our knowledge of the time evolution of the earthquake cycle processes. Fault slip mapping is critical to better understand the mechanical behavior of seismogenic zones and has fundamental implications for assessing hazards associated with megathrust earthquakes. However, numerous sources of errors can significantly affect the accuracy of the geophysical parameters deduced by InSAR. Among them, atmospheric phase delays caused by changes in the distribution of water vapor can lead to biased model parameter estimates and/or to difficulties in interpreting deformation events captured with InSAR. The hyper-arid climate of northern Chile might suggest that differential delays are of a minor importance for the application of InSAR techniques. Based on GPS, Moderate Resolution Imaging Spectroradiometer (MODIS) data our analysis shows that differential phase delays have typical amplitudes of about 20 mm and may exceptionally exceed 100 mm and then may impact the inferences of fault slip for even a Mw 8 earthquakes at 10% level. In this work, procedures for mitigating atmospheric effects in InSAR data using simultaneous MODIS time series are evaluated. We show that atmospheric filtering combined with stacking methods are particularly well suited to minimize atmospheric contamination in InSAR imaging and significantly reduce the impact of atmospheric delay on the determination of fundamental earthquake parameters.

L-phenylalanine mustard (L-PAM) is one of the most active agents for multiple myeloma (MM). The maximum tolerable dose of L-PAM is 240 mg/m 2 and less is used in combinations with busulfan or total body irradiation. The usual dose is 200 mg/m 2 followed by a stem cell (SC) infusion. We have performed a feasibility study to determine if 3 cycles of L-PAM (followed by autologous SC on the next day) could be delivered at 100 mg/m 2 at 3-week intervals on an outpatient basis. Three patients (pts) with chemoresponsive, stage III MM had peripheral blood SC mobilized with cyclophosphamide, prednisone and G-CSF. After CD34+ cell selection, SC were frozen in 3 aliquots. A backup SC collection was also cryopreserved. G-CSF was started day +1 and trovafloxacin and fluconazole were started day +5 after SC infusion. Of the 9 cycles, 1 cycle was delayed 1 week because of a central venous access line infection and there were 5 admissions: 3 for neutropenic fever and 1 each for mild enteritis and disseminated Herpes zoster. For pt 3, delayed ANC recoveries were seen despite acceptable numbers of CD34+ cells infused; for course 3, back-up SC were given when recovery appeared to be late and prompt engraftment ensued. All 3 pts showed reduction in their M-proteins. Next, pt 1 received alpha-interferon and pt 2 received thalidomide but pt 3 is TE. These 3 patients demonstrate that 300 mg/m 2 L-PAM can be delivered with ANC recovery in a space of 9 weeks with acceptable non-marrow toxicities.

Industrial societies have evolved under the influence of a political-economic reward system and a technological revolution that literally views the environment as infinite in its waste absorbing capabilities, if not in resource producing capability as well. As such they are not ecologically feasible in the long term. It is precisely their inconsistencies with the laws of material and energy balance under the pressures of an expanding human population that are generating the environmental crisis. The thesis of this paper is that man, as a dominating species on the surface of the earth, must learn to engineer the developments of industry, agriculture, and human habitats, giving explicit consideration to the effects of these developments on the environment. Environmental components are viewed as conceptually similar to industrial production processes, having many possible alternative uses. Since alternative uses are often mutually exclusive, the choice of use is critical. Some of the ecological and sociological considerations implicit in the problems of choice are demonstrated herein along with some of the problems of economic regulation.