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// Charlotte Taylor 1, 2 , David Mannion 1, 2 , Fabrizio Miranda 1, 2 , Mohammad Karaminejadranjbar 1, 2 , Sandra Herrero-Gonzalez 1, 2 , Karin Hellner 1, 2 , Yiyan Zheng 1, 2 , Geoffrey Bartholomeusz 3 , Robert C. Bast Jr 3 , Ahmed Ashour Ahmed 1, 2 1 Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK 2 Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Women’s Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK 3 Department of Experimental Therapeutics, M.D. Anderson Cancer Center, University of Texas, Houston, TX 77030, USA Correspondence to: Ahmed Ashour Ahmed, email: ahmed.ahmed@obs-gyn.ox.ac.uk Keywords: ovarian cancer, paclitaxel, mitotic arrest, PFKFB4, PFKFB3 Received: July 26, 2016 Accepted: December 15, 2016 Published: January 31, 2017 ABSTRACT Taxanes represent some of the most commonly used chemotherapeutic agents for ovarian cancer treatment. However, they are only effective in approximately 40% of patients. Novel therapeutic strategies are required to potentiate their effect and improve patient outcome. A hallmark of many cancers is the constitutive activation of the PI3K/AKT pathway, which drives cell survival and metabolism. We discovered a striking decrease in AKT activity coupled with a significant reduction in glucose 6-phosphate and ATP levels during mitotic arrest in the majority of ovarian cancer cell lines tested, indicating a potential metabolic vulnerability. A high-content siRNA screen to detect novel metabolic targets in mitotically arrested ovarian cancer cells identified the glycolytic enzyme PFKFB4. PFKFB4 depletion increased caspase 3/7 activity, and levels of reactive oxygen species only in mitotically arrested cells, and significantly enhanced mitotic cell death after paclitaxel treatment. Depletion of PFKFB3 demonstrated a similar phenotype. The observation that some ovarian cancer cells lose AKT activity during mitotic arrest and become vulnerable to metabolic targeting is a new concept in cancer therapy. Thus, combining mitotic-targeted therapies with glycolytic inhibitors may act to potentiate the effects of antimitotics in ovarian cancer through mitosis-specific cell death.

Summary A 15 month old boy with a ventricular septal defect (VSD) underwent percutaneous device closure of the VSD. Five days later he collapsed; on arrival to hospital he was asystolic and received prolonged cardio-pulmonary resuscitation (CPR) with intermittent return of spontaneous circulation (ROSC). He had recurrent episodic complete heart block with no ventricular escape rhythm, associated with loss of cardiac output, unresponsive to transcutaneous pacing. He was transferred to theatre, while receiving CPR, for urgent removal of the VSD device. Estimated total ‘down time’ was 70 min. The device was removed and patch closure of the VSD was performed. He made a full neurological recovery. Device closure of septal defects has become widespread. We discuss the incidence and type of arrythmias associated with their use. This case highlights an uncommon but life threatening complication of a VSD device. It also highlights that good quality CPR may lead to positive outcomes following pediatric cardiac arrest.

The adipocyte-rich microenvironment forms a niche for ovarian cancer metastasis, but the mechanisms driving this process are incompletely understood. Here we show that salt-inducible kinase 2 (SIK2) is overexpressed in adipocyte-rich metastatic deposits compared with ovarian primary lesions. Overexpression of SIK2 in ovarian cancer cells promotes abdominal metastasis while SIK2 depletion prevents metastasis in vivo. Importantly, adipocytes induce calcium-dependent activation and autophosphorylation of SIK2. Activated SIK2 plays a dual role in augmenting AMPK-induced phosphorylation of acetyl-CoA carboxylase and in activating the PI3K/AKT pathway through p85α-S154 phosphorylation. These findings identify SIK2 at the apex of the adipocyte-induced signaling cascades in cancer cells and make a compelling case for targeting SIK2 for therapy in ovarian cancer.

Patients undergoing surgery for idiopathic scoliosis were studied to determine the incidence and aetiology of oliguria during the perioperative period and to evaluate the efficacy of low dose dopamine in preventing its occurrence. Thirty patients, aged 6-18 years undergoing elective surgery were studied. Anaesthesia was standardized. Patients were randomized to receive either dopamine infusion (3 micrograms.kg-1.min-1) (Group A) (n = 15) or dextrose infusion (control) (Group B) (n = 15). Serum and urinary electrolytes and osmolalities and serum antidiuretic hormone (ADH) concentrations were measured. Urine output and haemodynamic parameters were recorded. Intraoperative oliguria occurred in 7% of patients in Group A and 47% in Group B (P 0.05). Urine and serum biochemical analysis revealed a statistically significant decrease in serum sodium and osmolality (P < 0.005) and an increase in urinary sodium and osmolality in both groups. Serum ADH concentrations were increased in both groups (P < 0.05), returning to baseline 18 h postoperatively. We conclude that oliguria during corrective spinal surgery occurs in association with excess ADH secretion as opposed to perioperative hypovolaemia. Dopamine increases urine output in the perioperative period but does not prevent the release of ADH and its subsequent biochemical effects.

Background: High Grade Serous Ovarian Cancer (HGSOC) metastatic disease is strongly dependent on the adipocyte-rich microenvironment of the omentum. Altough previous work has shown that adipocytes are required for driving cancer metastasis to fat-rich environments, the mechanisms involved in the process of linking metabolism to cancer cell survival at this niche have remained poorly understood and this has, therefore, hindered therapeutic exploitation. We have previously shown that the expression of the Salt Inducible Kinase 2 (SIK2) is important for ovarian cancer cell survival and that it correlates with poor patient survival (Ahmed et al., Cancer Cell, 2010). In this work we present a previously unrecognised role for SIK2 in driving cancer cell metabolism and proliferation at the omental metastatic niche. Methods: We established a system for the co-culture of cancer cells with adipocytes obtained from freshly excised normal omentum from women undergoing surgical staging. This system was used in combination with a chemical biology approach utilizing cells expressing gate-keeper mutants of SIK2 and a type I kinase inhibitor to test the specificity of observed phenotypic effects. Our results were validated using immunohistochemistry of a panel of ovarian cancers and a xenograft model of ovarian cancer metastasis. Results: SIK2 was significantly overexpressed in omental metastases of ovarian tumours compared to paired ovarian cancer primary lesions from the same patients. In a xenograft model of ovarian cancer metastasis SIK2-overexpressing cells implanted orthotopically at the ovarian bursa formed significantly larger omental metastases compared to cells with endogenous levels of SIK2. We first observed that co-culture of ovarian cancer cells with adipocytes resulted in an increased SIK2 autophosphorylation and activation which, in turn stimulated cancer cell proliferation. Next, we showed that PLC-dependent activation of calcium release was required for adipocyte-induced SIK2 autophosphorylation in ovarian cancer cells. Surprisingly, we identified a role for adipocyte-activated SIK2 in stimulating cancer cell metabolism throught augmenting AMPK-induced phosphorylation of ACC and activation of carnitine palmitoyltransferase 1 (CPT1) transcription. Concurrently, SIK2 was required to activate the PI3K complex through direct p85α-S154 phosphorylation. This was confirmed using rapamycin as a known robust paradoxical PI3K activator showing that SIK2 siRNA-mediated depletion or its chemical inhibition abolished rapamycin-induced AKT phosphorylation and sensitized ovarian cancer cells to its cytotoxic effect. Conclusion: Our results suggested that SIK2 phosphorylation and activation were required to establish ovarian cancer lesions at the adipocyte-rich omental environment. Therefore we suggest a therapeutic role for targeting SIK2 in preventing ovarian cancer metastases. Citation Format: Fabrizio Miranda, Shujuan Liu, Sandra Herrero-Gonzalez, David Mannion, Stefan Knapp, Ahmed A. Ahmed. The salt inducible kinase 2 (SIK2) links lipid metabolism to survival of ovarian cancer metastasis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4111. doi:10.1158/1538-7445.AM2015-4111

Inhalation induction using isoflurane is associated with airway irritability, coughing, breath-holding and laryngospasm. These complications are more common in children. This study was designed to determine if humidification of isoflurane in oxygen/nitrous oxide would reduce respiratory complications and hypoxic episodes at induction.Fifty-nine unpremedicated children, aged three months to 12 yr, were enrolled in the study and randomised to receive either humidified isoflurane (n = 27, Group A), or non-humidified isoflurane (n = 32, Group B). All inductions of anaesthesia were with isoflurane 4% in 50% oxygen/nitrous oxide. Subjects were observed for the occurrence of breath-holding, coughing, laryngospasm, bronchospasm, secretions, and hiccoughs. The severity of each complication was graded on a scale of 0-3. The need to administer 100% oxygen and/or succinylcholine was also identified.Coughing (33% vs 53%) was more frequent in Group B (P0.05). Coughing severity scores (13 vs 36) and breath-holding severity scores (8 vs 19) were also greater in Group B (P0.05). A change in FIO2 was required more frequently in Group B (4% vs 16%). Although there was a high incidence of laryngospasm in both groups (52% vs 59%), no other differences were identified, breath-holding (26% vs 31%), secretions (30% vs 31%), hiccough (11% vs 12.5%) (P0.05).Humidification of inspired isoflurane reduces the frequency and severity of coughing, the severity of breath-holding, and the need to increase supplemental inspired oxygen concentration, when isoflurane is used for inhalation induction of anaesthesia in children. Humidification has no effect, however, on the frequency and severity of laryngospasm, or on the frequency of occurrence of arterial oxygen desaturation.

Background Spinal cord perfusion pressure may be reduced when sodium nitroprusside is used to control proximal aortic hypertension during thoracic aortic clamping. The effect of esmolol infusion on spinal cord perfusion pressure during thoracic aortic clamping is unknown. This study compares spinal cord perfusion pressure following control of proximal hypertension with either sodium nitroprusside or esmolol during thoracic aortic clamping. Methods The thoracic aorta was cross-clamped for 30 min in 18 dogs anesthetized with halothane. A control group (n = 6) received no treatment of proximal hypertension during cross-clamping. In two other groups, proximal arterial pressure was controlled (100 mmHg) by infusion of either sodium nitroprusside (n = 6) or esmolol (n = 6). Brachial and femoral arterial pressures, spinal cord perfusion pressure, pulmonary artery occlusion, central venous pressures, and cardiac output were monitored. Neurologic assessment was performed 24 h following surgery. Results Femoral arterial pressure was lower with nitroprusside (14 +/- 3 mmHg) compared to esmolol (24 +/- 4 mmHg) after 15 min of aortic cross-clamping. Cerebrospinal fluid pressure increased during aortic cross-clamping in the sodium nitroprusside group (from 7 +/- 5 to 16 +/- 6 mmHg) but not in esmolol or control groups. Spinal cord perfusion pressure was lower with nitroprusside at 15 min of aortic cross-clamping (2 +/- 4 mmHg) compared to control (15 +/- 7 mmHg) and esmolol groups (17 +/- 11 mmHg). Esmolol infusion reduced cardiac output and increased ventricular filling pressures compared to control and nitroprusside groups. Conclusions Esmolol was associated with greater spinal cord perfusion pressure, but adverse hemodynamic effects, when compared with nitroprusside during thoracic aortic cross-clamping. When only surviving dogs (4 control, 5 esmolol, 6 nitroprusside) are considered, the incidence of neurologic deficit was greater in nitroprusside-treated dogs than in either control or esmolol-treated dogs. No difference in outcome was present when all dogs are considered.