Treatment Adherence and Adherence Patterns of Tofacitinib and Self-Injectable TNFi Use in People with Rheumatoid Arthritis

OBJECTIVE

To assess tofacitinib and self-injectable tumor necrosis factor inhibitor (TNFi) adherence using the Medication Event Monitoring System (MEMS) and characterize association with adherence in patients with rheumatoid arthritis (RA).

METHODS

Eligible patients were enrolled from the Forward Databank within 6 months of initiating tofacitinib or injectable TNFi or from participating clinics where these were first prescribed. MEMS caps and patient diaries were used to compile dosing over 9 months. Demographics and disease characteristics were collected every 6 months, and the Beliefs about Medicines Questionnaire only at baseline. Adherence along with its components, initiation, implementation, and persistence, were calculated.

RESULTS

Of the 112 consented to participate, 82 (73%) remained in the final analysis with recruitment from clinics 47 (57%) and Forward 35 (43%). Sixty-two (76%) initiated tofacitinib with 87% taking it quaque die and twenty (24%) TNFi. At 9 months, 77% of tofacitinib were persistent versus 70% for TNFi (P = 0.65), and implementation was similar (0.84 vs. 0.82; P = 0.57). In multivariable models, increased baseline patient global assessment was consistently associated with discontinuation (hazard ratio 1.31 [1.07-1.61]). There was increased adherence to methotrexate (MTX) when taking tofacitinib that led to higher combined adherence for tofacitinib than TNFi (0.81 vs. 0.69; P = 0.03), but no significant differences remained in multivariable models. In sensitivity analysis, consistent morning intake for tofacitinib and evening intake for MTX was associated with improved adherence.

CONCLUSION

We found no statistical differences in adherence between patients with RA initiating tofacitinib and self-injectable TNFi, although 15% to 30% were nonadherent. Concomitant MTX, patient global assessment, and a consistent time of day intake were associated with adherence.

PARKIN UBIQUITINATION OF KINDLIN-2 ENABLES MITOCHONDRIA-ASSOCIATED METASTASIS SUPPRESSION

Mitochondria are signaling organelles implicated in cancer, but the mechanisms are elusive. Here, we show that Parkin, an E3 ubiquitin ligase altered in Parkinson's Disease (PD), forms a complex with the regulator of cell motility, Kindlin-2 (K2) at mitochondria of tumor cells. In turn, Parkin ubiquitinates Lys581 and Lys582 using Lys48 linkages, resulting in proteasomal degradation of K2 and shortened half-life from ∼5 h to ∼1.5 h. Loss of K2 inhibits focal adhesion turnover and β1 integrin activation, impairs membrane lamellipodia size and frequency, and inhibits mitochondrial dynamics, altogether suppressing tumor cell-ECM interactions, migration, and invasion. Conversely, Parkin does not affect tumor cell proliferation, cell cycle transitions or apoptosis. Expression of a Parkin ubiquitination-resistant K2 Lys581Ala/Lys582Ala double mutant is sufficient to restore membrane lamellipodia dynamics, correct mitochondrial fusion/fission, and preserve single-cell migration and invasion. In a 3D model of mammary gland developmental morphogenesis, impaired K2 ubiquitination drives multiple oncogenic traits of EMT, increased cell proliferation, reduced apoptosis and disrupted basal-apical polarity. Therefore, deregulated K2 is a potent oncogene and its ubiquitination by Parkin enables mitochondria-associated metastasis suppression.

Clinical and Electrophysiological Factors Predicting Prolonged Recovery in Children with Guillain-Barré Syndrome

OBJECTIVE

To compare clinical and nerve conduction studies (NCS) parameters predictive of outcome in children with acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN).

METHODS

In this prospective observational study, NCS was done on all children at admission and repeated before discharge. Functional status of patients was graded as per Hughes Disability score. These children were followed up till they achieved independent walking. Clinical and NCS criteria were compared between (a) AMAN and AIDP and (b) two subgroups of children with AMAN-those who achieved early (within 60 d) versus delayed (i.e., after 60 d) walking.

RESULTS

Fifty-seven children were initially enrolled, first NCS showed inexcitable nerves in 10, AMAN in 29, acute motor-sensory axonal neuropathy (AMSAN) in 3, AIDP in 13, and 2 were normal. Subsequent NCS showed AMAN in 37, AIDP in 15, AMSAN in 3 patients. There were no deaths, 16 required ventilation. Follow-up till independent walking, was available for 40 patients. AMAN was associated with faster progression, greater peak disability, prolonged hospital stay, and delayed walking (p < 0.05). Asymmetrical nerve involvement predicted prolonged hospital stay as well as delayed walking. In the AMAN group, prolonged ulnar F-wave latencies were significantly associated with delayed walking (p = 0.02).

CONCLUSION

Long term prognosis of pediatric GBS is generally satisfactory. AMAN, asymmetric involvement and prolonged ulnar F-wave latencies in children with AMAN were associated with delayed walking.

Real-world evaluation of rapid and laboratory-free COVID-19 triage for emergency care: external validation and pilot deployment of artificial intelligence driven screening

Background

Uncertainty in patients' COVID-19 status contributes to treatment delays, nosocomial transmission, and operational pressures in hospitals. However, the typical turnaround time for laboratory PCR remains 12–24 h and lateral flow devices (LFDs) have limited sensitivity. Previously, we have shown that artificial intelligence-driven triage (CURIAL-1.0) can provide rapid COVID-19 screening using clinical data routinely available within 1 h of arrival to hospital. Here, we aimed to improve the time from arrival to the emergency department to the availability of a result, do external and prospective validation, and deploy a novel laboratory-free screening tool in a UK emergency department.

Methods

We optimised our previous model, removing less informative predictors to improve generalisability and speed, developing the CURIAL-Lab model with vital signs and readily available blood tests (full blood count [FBC]; urea, creatinine, and electrolytes; liver function tests; and C-reactive protein) and the CURIAL-Rapide model with vital signs and FBC alone. Models were validated externally for emergency admissions to University Hospitals Birmingham, Bedfordshire Hospitals, and Portsmouth Hospitals University National Health Service (NHS) trusts, and prospectively at Oxford University Hospitals, by comparison with PCR testing. Next, we compared model performance directly against LFDs and evaluated a combined pathway that triaged patients who had either a positive CURIAL model result or a positive LFD to a COVID-19-suspected clinical area. Lastly, we deployed CURIAL-Rapide alongside an approved point-of-care FBC analyser to provide laboratory-free COVID-19 screening at the John Radcliffe Hospital (Oxford, UK). Our primary improvement outcome was time-to-result, and our performance measures were sensitivity, specificity, positive and negative predictive values, and area under receiver operating characteristic curve (AUROC).

Findings

72 223 patients met eligibility criteria across the four validating hospital groups, in a total validation period spanning Dec 1, 2019, to March 31, 2021. CURIAL-Lab and CURIAL-Rapide performed consistently across trusts (AUROC range 0·858–0·881, 95% CI 0·838–0·912, for CURIAL-Lab and 0·836–0·854, 0·814–0·889, for CURIAL-Rapide), achieving highest sensitivity at Portsmouth Hospitals (84·1%, Wilson's 95% CI 82·5–85·7, for CURIAL-Lab and 83·5%, 81·8–85·1, for CURIAL-Rapide) at specificities of 71·3% (70·9–71·8) for CURIAL-Lab and 63·6% (63·1–64·1) for CURIAL-Rapide. When combined with LFDs, model predictions improved triage sensitivity from 56·9% (51·7–62·0) for LFDs alone to 85·6% with CURIAL-Lab (81·6–88·9; AUROC 0·925) and 88·2% with CURIAL-Rapide (84·4–91·1; AUROC 0·919), thereby reducing missed COVID-19 cases by 65% with CURIAL-Lab and 72% with CURIAL-Rapide. For the prospective deployment of CURIAL-Rapide, 520 patients were enrolled for point-of-care FBC analysis between Feb 18 and May 10, 2021, of whom 436 received confirmatory PCR testing and ten (2·3%) tested positive. Median time from arrival to a CURIAL-Rapide result was 45 min (IQR 32–64), 16 min (26·3%) sooner than with LFDs (61 min, 37–99; log-rank p<0·0001), and 6 h 52 min (90·2%) sooner than with PCR (7 h 37 min, 6 h 5 min to 15 h 39 min; p<0·0001). Classification performance was high, with sensitivity of 87·5% (95% CI 52·9–97·8), specificity of 85·4% (81·3–88·7), and negative predictive value of 99·7% (98·2–99·9). CURIAL-Rapide correctly excluded infection for 31 (58·5%) of 53 patients who were triaged by a physician to a COVID-19-suspected area but went on to test negative by PCR.

Interpretation

Our findings show the generalisability, performance, and real-world operational benefits of artificial intelligence-driven screening for COVID-19 over standard-of-care in emergency departments. CURIAL-Rapide provided rapid, laboratory-free screening when used with near-patient FBC analysis, and was able to reduce the number of patients who tested negative for COVID-19 but were triaged to COVID-19-suspected areas.

Funding

The Wellcome Trust, University of Oxford Medical and Life Sciences Translational Fund.

Ghost mitochondria drive metastasis through adaptive GCN2/Akt therapeutic vulnerability

Cancer metabolism, including in mitochondria, is a disease hallmark and therapeutic target, but its regulation is poorly understood. Here, we show that many human tumors have heterogeneous and often reduced levels of Mic60, or Mitofilin, an essential scaffold of mitochondrial structure. Despite a catastrophic collapse of mitochondrial integrity, loss of bioenergetics, and oxidative damage, tumors with Mic60 depletion slow down cell proliferation, evade cell death, and activate a nuclear gene expression program of innate immunity and cytokine/chemokine signaling. In turn, this induces epithelial-mesenchymal transition (EMT), activates tumor cell movements through exaggerated mitochondrial dynamics, and promotes metastatic dissemination in vivo. In a small-molecule drug screen, compensatory activation of stress response (GCN2) and survival (Akt) signaling maintains the viability of Mic60-low tumors and provides a selective therapeutic vulnerability. These data demonstrate that acutely damaged, "ghost" mitochondria drive tumor progression and expose an actionable therapeutic target in metastasis-prone cancers.

A Clinical Study to Evaluate the Association Between Metabolic Syndrome and Sensorineural Hearing Loss

Metabolic syndrome is considered to be a triggering factor for deterioration of health related quality of life. In present study we assessed hearing loss consequent to metabolic syndrome. A total of 100 patients diagnosed for metabolic syndrome (IDF criteria) were included in the study. All the patients underwent pure tone audiometry and impedance audiometry. All the patients underwent anthropometric measurements, lipid profile, blood sugar and blood pressure assessments. Data was analyzed using SPSS 21.0 software. A total of 62% patients had sensorineural hearing loss. Maximum (35%) had mild hearing loss, followed by moderate hearing loss (23%). Only 4 (4%) cases had severe hearing loss. Older age, wider waist circumference, higher fasting blood glucose levels and lower blood pressure were found to be significantly associated with sensorineural hearing loss and its severity on univariate analysis. However, on multivariate assessment only age and waist circumference showed a significant association with hearing loss.

Changes in Disease-Modifying Antirheumatic Drug Treatment for Patients With Rheumatoid Arthritis in the US During the COVID-19 Pandemic: A Three-Month Observational Study

Objective

To understand medication, lifestyle, and clinical care changes of persons with rheumatoid arthritis (RA) during the first months (March 2020 through May 2020) of the COVID‐19 pandemic in the US.

Methods

Data were collected from adults with RA participating in FORWARD, The National Databank for Rheumatic Diseases observational registry, who answered COVID‐19 web‐based surveys in May 2020 and previously provided baseline characteristics and medication use prior to the US COVID‐19 pandemic. We compared medication changes by disease‐modifying antirheumatic drug (DMARD) exposure in logistic models that were adjusted for age, sex, comorbidities including pulmonary and cardiovascular diseases, education level, health insurance status, RA disease activity, fatigue, and polysymptomatic distress.

Results

Of 734 respondents, 221 (30%) reported medication changes. Among respondents who experienced a medication change, i.e., “medication changers/changers,” glucocorticoids (GCs) were more commonly used compared to respondents who did not experience a medication change (“non‐changers”) (33% versus 18%). Non‐hydroxychloroquine conventional DMARDs were less commonly used in changers compared to non‐changers pre–COVID‐19 (49% versus 62%), and changers reported more economic hardship during the COVID‐19 pandemic compared to non‐changers (23% versus 15%). While JAK inhibitor use was associated with the likelihood of a medication change, with an odds ratio (OR) of 1.9 (95% confidence interval [95% CI] 1.0, 3.4), only pre‐COVID GC use remained a strong predictor for medication change in multivariable models (OR 3.0 [95% CI 1.9, 4.9]). Change in care was observed to have a significant association with pulmonary disease (OR 2.9 [95% CI 1.3, 6.5]), worse RA disease activity (OR 1.1 [95% CI 1.0, 1.1]), and GC use (OR 1.6 [95% CI 1.0, 2.5]). While the incidence of medication changes was the same before and after the American College of Rheumatology (ACR) guidance for the management of rheumatic disease in adult patients during the COVID‐19 pandemic were first published in April 2020, self‐imposed changes in medication were approximately twice as likely before publication of the guidelines, and physician‐guided changes were more likely after publication.

Conclusion

Persons with RA in the US made substantial medication changes during the first three months of the COVID‐19 pandemic, and changes among persons with RA after publication of the ACR guidance in April 2020 were made with increased physician guidance.

A cancer ubiquitome landscape identifies metabolic reprogramming as target of Parkin tumor suppression

Changes in metabolism that affect mitochondrial and glycolytic networks are hallmarks of cancer, but their impact in disease is still elusive. Using global proteomics and ubiquitome screens, we now show that Parkin, an E3 ubiquitin ligase and key effector of mitophagy altered in Parkinson's disease, shuts off mitochondrial dynamics and inhibits the non-oxidative phase of the pentose phosphate pathway. This blocks tumor cell movements, creates metabolic and oxidative stress, and inhibits primary and metastatic tumor growth. Uniformly down-regulated in cancer patients, Parkin tumor suppression requires its E3 ligase function, is reversed by antioxidants, and is independent of mitophagy. These data demonstrate that cancer metabolic networks are potent oncogenes directly targeted by endogenous tumor suppression.

Significant treatment gap and co-morbidities identified in an epidemiological survey of pediatric epilepsy in rural suburbs of India

PURPOSE

A cross-sectional epidemiological survey of children was conducted in two rural clusters to estimate the point prevalence and study various aspects of childhood epilepsy.

MATERIAL AND METHODS

In the first stage, a house-to-house survey was conducted by health workers using a screening questionnaire, which was pre-validated in a pilot study. All screen positive houses were visited by pediatric neurologist for detailed evaluation. Children with a clinical diagnosis of epilepsy underwent EEG and were evaluated for type of seizure, epilepsy syndrome, etiology, co-morbidities and treatment gap. Knowledge, attitude and practice regarding epilepsy was assessed amongst caregivers of the affected children.

RESULTS

A total population of 75,455 population was screened, 19,181 children aged 2 months to 18 years were identified. Out of 355 screen positive children, 66 were diagnosed with epilepsy. The point prevalence of pediatric epilepsy was 3.44 per 1000 children. 53% had focal epilepsy, 31.8% had an identifiable epilepsy syndrome, 44% had at least one comorbidity. The etiology was identified in 68%, the commonest being perinatal brain insult. The magnitude of treatment gap was 45.45%, with significant deficits in knowledge.

CONCLUSION

There are significant deficits in diagnosis and treatment of pediatric epilepsy among the rural population of India. The existing rural health care facilities need to be augmented to facilitate the timely diagnosis and optimum care of these children, including care of associated co-morbidities.

Resurgence of Subacute Sclerosing Panencephalitis: Case Series and Global Epidemiological Trends

Resurgence of subacute sclerosing panencephalitis (SSPE)—case series and global epidemiological trends. We noted a recent increase in cases of SSPE admitted in our institute, even though they had received measles vaccination. We did a detailed study of our cases and compared with global epidemiological trends of SSPE in preimmunization and era of developed immunity. Out of total 23 cases of SSPE, 12 presented in the year 2017 alone, reflecting a steep rise in incidence. Sixteen patients had received measles vaccine and never had prior measles infection. Mean age of onset was 8.2 years and average time of progression to advanced stage of disease was 65 days. Global data showed similar trends, that is, earlier age of onset with a faster rate of progression in the postvaccination era as compared with prevaccine era. Possible mechanisms to account for this trend include an early wild measles infection in the critical age of 6 to 9 months, before vaccination. There is a changing epidemiological trend of SSPE in terms of lower age of onset and faster rate of progression, also reflected in global data. There is a need for multicenter studies to verify the findings and explore possible measures like lowering the age of measles vaccination to halt this alarming trend.

Ward-based nutrition care practices and a snapshot of patient care: Results from nutritionDay in the ICU

BACKGROUND

Poor adherence to intensive care unit (ICU) guidelines is common, leading to suboptimal nutritional care. This study determined current ward-based nutrition care practices in the Indian ICU setting, comparing them to international best-practice guidelines and provided patient demographic, clinical and nutritional information to serve as baseline data for future benchmarking.

METHODS

This multi-site cross-sectional retrospective study analysed data collected from nutritionDay worldwide audits (2012-2016) across ICUs from a chain of urban private hospitals in India. Additional guideline-specific data were collected through questionnaires and phone interviews with the Head of Dietetics Departments in the participating hospitals.

RESULTS

Overall, 10 ICUs and 457 participants were included. It was common practice to use modified versions of the Mini Nutritional Assessment-Short Form (MNA-SF) and Subjective Global Assessment (SGA) for nutrition screening and assessment. Nearly half the participants (n = 222, 49%) received nutrition orally. A majority of the remaining participants received enteral nutrition (n = 163, 36%) or no nutrition (n = 60, 13%) at the time of data collection. The calories prescribed for most participants were between 1500 and 1999 kilocalories per day (n = 207, 45%), with no nutrition planned for 115 (25%) participants. Three-quarters (n = 129, 74%) of participants on EN received the planned calories, while 24% (n = 42) were given less than planned.

CONCLUSION

Overall, most participants received the calories planned for enteral nutrition. The use of modified screening and assessment tools and suboptimal delivery of EN remains a global problem for critical care, possibly requiring a more pragmatic approach to nutritional therapy.

Abstract 1457: Akt phosphorylation of mitochondrial Lonp1 protease enables oxidative metabolism and advanced tumor traits

Introduction: The control of protein homeostasis, or proteostasis is essential for cellular adaptation to disparate environmental cues and relies on protein (re)folding or proteolytic removal of aggregated or misfolded proteins. Defective proteostasis can irreversibly impair organelle functions and activate cell death through an unfolded protein response. Tumor mitochondria have heightened protein folding quality control, but the regulators of this process and how they impact cancer traits are not completely understood. In this study, we investigated the mechanisms of stress-regulated LonP1 (ATP-dependent protease) in tumor mitochondria and their implications for advanced cancer traits.

Experimental procedures: We monitored kinase activity in immunoprecipitation, protein expression by immunoblotting, mitochondrial ROS quantification in live cells, mitochondrial electron transport chain (ETC) activity, mitochondria time-lapse video microscopy, protein folding, proteomics analysis, mitochondrial bioenergetics, mitochondrial trafficking and tumor cell motility, and tumor growth and metastasis. A xenograft prostate cancer model was used to study antitumor activity in vivo.

Results: We showed that the ATP-directed mitochondrial protease, LonP1 is upregulated by stress conditions, including hypoxia, in tumor, but not normal cells. In mitochondria, LonP1 is phosphorylated by Akt on Ser173 and Ser181, enhancing its protease activity. Interference with this pathway induces accumulation of misfolded subunits of electron transport chain complex II and complex V, resulting in impaired oxidative bioenergetics and heightened ROS production. Functionally, this suppresses mitochondrial trafficking to the cortical cytoskeleton, shuts off tumor cell migration and invasion, and inhibits primary and metastatic tumor growth, in vivo.

Conclusion: These data identify LonP1 as a key effector of mitochondrial reprogramming in cancer and potential therapeutic target.

Citation Format: Jagadish C. ghosh, Jae Ho Seo, Ekta Agarwal, Yuan Wang, Andrew V. Kossenkov, Hsin-Yao Tang, David W. Speicher, Dario C. Altieri. Akt phosphorylation of mitochondrial Lonp1 protease enables oxidative metabolism and advanced tumor traits [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1457.

The mitophagy effector FUNDC1 controls mitochondrial reprogramming and cellular plasticity in cancer cells

Mitochondria are signaling hubs in eukaryotic cells. Here, we showed that the mitochondrial FUN14 domain-containing protein-1 (FUNDC1), an effector of Parkin-independent mitophagy, also participates in cellular plasticity by sustaining oxidative bioenergetics, buffering ROS production, and supporting cell proliferation. Targeting this pathway in cancer cells suppressed tumor growth but rendered transformed cells more motile and invasive in a manner dependent on ROS-mediated mitochondrial dynamics and mitochondrial repositioning to the cortical cytoskeleton. Global metabolomics and proteomics profiling identified a FUNDC1 interactome at the mitochondrial inner membrane, comprising the AAA+ protease, LonP1, and subunits of oxidative phosphorylation, complex V (ATP synthase). Independently of its previously identified role in mitophagy, FUNDC1 enabled LonP1 proteostasis, which in turn preserved complex V function and decreased ROS generation. Therefore, mitochondrial reprogramming by a FUNDC1-LonP1 axis controls tumor cell plasticity by switching between proliferative and invasive states in cancer.

The αvβ6 integrin in cancer cell-derived small extracellular vesicles enhances angiogenesis

Prostate cancer (PrCa) cells crosstalk with the tumour microenvironment by releasing small extracellular vesicles (sEVs). sEVs, as well as large extracellular vesicles (LEVs), isolated via iodixanol density gradients from PrCa cell culture media, express the epithelial-specific αvβ6 integrin, which is known to be induced in cancer. In this study, we show sEV-mediated protein transfer of αvβ6 integrin to microvascular endothelial cells (human microvascular endothelial cells 1 - HMEC1) and demonstrate that de novo αvβ6 integrin expression is not caused by increased mRNA levels. Incubation of HMEC1 with sEVs isolated from PrCa PC3 cells that express the αvβ6 integrin results in a highly significant increase in the number of nodes, junctions and tubules. In contrast, incubation of HMEC1 with sEVs isolated from β6 negative PC3 cells, generated by shRNA against β6, results in a reduction in the number of nodes, junctions and tubules, a decrease in survivin levels and an increase in a negative regulator of angiogenesis, pSTAT1. Furthermore, treatment of HMEC1 with sEVs generated by CRISPR/Cas9-mediated down-regulation of β6, causes up-regulation of pSTAT1. Overall, our findings suggest that αvβ6 integrin in cancer sEVs regulates angiogenesis during PrCa progression.

Feasibility of using the "modified NUTrition Risk In the Critically ill" nutritional risk screening tool to identify nutritionally at-risk patients in an Australian intensive care unit

BACKGROUND

The modified NUTrition Risk In the Critically ill (mNUTRIC) score has been demonstrated to accurately quantify the risk of negative patient outcomes and discriminate which patients will benefit the most from nutrition intervention in an intensive care unit (ICU) setting. Calculation of an mNUTRIC score, however, may be time-intensive and unable to be performed within available resources. This may prevent high-risk patients from being identified and reviewed by a dietitian.

OBJECTIVES

The purpose of this study was to assess the feasibility of using the mNUTRIC tool to screen for patients at increased nutrition risk and to determine the proportion of those high-risk patients who were reviewed by a dietitian.

SUBJECTS/METHODS

A retrospective observational study of 260 critically ill patients was conducted between 01/01/2017 and 30/05/2017 in a 20-bed Australian tertiary ICU. Participants included all adults admitted to the ICU for more than 72 h. Feasible implementation was defined as calculating an mNUTRIC score in <5 min per patient where all data were available for >90% of patients.

RESULTS

A median time of 4 min and 54 s (interquartile range: 4.3-5.6 min) was required to calculate each mNUTRIC score, with 96% of scores calculated in <10 min. Data were available to calculate mNUTRIC scores for 93% (241/260) of patients. The mNUTRIC tool identified 81 patients at high nutrition risk, 44% (36/81) of whom were not reviewed by a dietitian. There were 21 high-risk patients who were purposefully excluded from dietetic review for various clinical reasons, leaving 15 high-risk patients (19%) who were not reviewed by a dietitian.

CONCLUSIONS

Implementation of the mNUTRIC tool was not feasible in our ICU, given the set dietetic resources (0.6 full-time equivalent). Shared responsibility of nutrition screening or automating the calculation may be possible solutions to increase feasibility of mNUTRIC screening.

MFF Regulation of Mitochondrial Cell Death Is a Therapeutic Target in Cancer

The regulators of mitochondrial cell death in cancer have remained elusive, hampering the development of new therapies. Here, we showed that protein isoforms of mitochondrial fission factor (MFF1 and MFF2), a molecule that controls mitochondrial size and shape, that is, mitochondrial dynamics, were overexpressed in patients with non-small cell lung cancer and formed homo- and heterodimeric complexes with the voltage-dependent anion channel-1 (VDAC1), a key regulator of mitochondrial outer membrane permeability. MFF inserted into the interior hole of the VDAC1 ring using Arg225, Arg236, and Gln241 as key contact sites. A cell-permeable MFF Ser223-Leu243 d-enantiomeric peptidomimetic disrupted the MFF-VDAC1 complex, acutely depolarized mitochondria, and triggered cell death in heterogeneous tumor types, including drug-resistant melanoma, but had no effect on normal cells. In preclinical models, treatment with the MFF peptidomimetic was well-tolerated and demonstrated anticancer activity in patient-derived xenografts, primary breast and lung adenocarcinoma 3D organoids, and glioblastoma neurospheres. These data identify the MFF-VDAC1 complex as a novel regulator of mitochondrial cell death and an actionable therapeutic target in cancer. SIGNIFICANCE: These findings describe mitochondrial fission regulation using a peptidomimetic agent that disturbs the MFF-VDAC complex and displays anticancer activity in multiple tumor models.See related commentary by Rao, p. 6074.

Mitochondrial fission factor is a novel Myc-dependent regulator of mitochondrial permeability in cancer

Background

Mitochondrial functions are exploited in cancer and provide a validated therapeutic target. However, how this process is regulated has remained mostly elusive and the identification of new pathways that control mitochondrial integrity in cancer is an urgent priority.

Methods

We studied clinically-annotated patient series of primary and metastatic prostate cancer, representative cases of multiple myeloma (MM) and publicly available genetic databases. Gene regulation studies involved chromatin immunoprecipitation, PCR amplification and Western blotting of conditional Myc-expressing cell lines. Transient or stable gene silencing was used to quantify mitochondrial functions in bioenergetics, outer membrane permeability, Ca²⁺ homeostasis, redox balance and cell death. Tumorigenicity was assessed by cell proliferation, colony formation and xenograft tumour growth.

Findings

We identified Mitochondrial Fission Factor (MFF) as a novel transcriptional target of oncogenic Myc overexpressed in primary and metastatic cancer, compared to normal tissues. Biochemically, MFF isoforms, MFF1 and MFF2 associate with the Voltage-Dependent Anion Channel-1 (VDAC1) at the mitochondrial outer membrane, in vivo. Disruption of this complex by MFF silencing induces general collapse of mitochondrial functions with increased outer membrane permeability, loss of inner membrane potential, Ca²⁺ unbalance, bioenergetics defects and activation of cell death pathways. In turn, this inhibits tumour cell proliferation, suppresses colony formation and reduces xenograft tumour growth in mice.

Interpretation

An MFF-VDAC1 complex is a novel regulator of mitochondrial integrity and actionable therapeutic target in cancer.

IDH2 reprograms mitochondrial dynamics in cancer through a HIF-1α-regulated pseudohypoxic state

The role of mitochondria in cancer continues to be debated and paradoxically implicated in opposing functions in tumor growth and tumor suppression. To understand this dichotomy, we explored the function of mitochondrial isocitrate dehydrogenase (IDH)2, a tricarboxylic acid cycle enzyme mutated in subsets of acute leukemias and gliomas, in cancer. Silencing of IDH2 in prostate cancer cells impaired oxidative bioenergetics, elevated reactive oxygen species (ROS) production, and promoted exaggerated mitochondrial dynamics. This was associated with increased subcellular mitochondrial trafficking, turnover of membrane focal adhesion complexes, and enhanced tumor cell migration and invasion, without changes in cell cycle progression. Mechanistically, loss of IDH2 caused ROS-dependent stabilization of hypoxia-inducible factor-1α in normoxia, which was required for increased mitochondrial trafficking and tumor cell movements. Therefore, IDH2 is a dual regulator of cancer bioenergetics and tumor cell motility. This pathway may reprogram mitochondrial dynamics to differentially adjust energy production or promote tumor cell invasion in response to microenvironment conditions.-Wang, Y., Agarwal, E., Bertolini, I., Ghosh, J. C., Seo, J. H., Altieri, D. C. IDH2 reprograms mitochondrial dynamics in cancer through a HIF-1α-regulated pseudohypoxic state.

Real-World Adherence to Oral Methotrexate Measured Electronically in Patients With Established Rheumatoid Arthritis

Objective

To assess methotrexate (MTX) adherence using the Medication Event Monitoring System (MEMS) and characterize associations with adherence in patients with rheumatoid arthritis (RA).

Methods

Eligible patients participated in Forward, the National Databank for Rheumatic Diseases, and recently (12 months or sooner) initiated oral MTX. MEMS was used to compile MTX weekly dosing over 24 weeks. The Beliefs about Medicines Questionnaire (BMQ) was completed, and baseline demographics and disease characteristics obtained. MTX adherence (percentage of weeks dose taken correctly), implementation (percentage of weeks dose taken correctly from initiation until last dose), and persistence (duration from initiation to last dose) were calculated. Analyses measured associations between patient characteristics and adherence, modeled using logistic generalized estimating equations and censored Poisson regression, and persistence modeled using Cox regression.

Results

Overall, 60 of 119 eligible patients were included in the analysis. MTX adherence, implementation, and persistence were 75%, 80%, and 83%, respectively, at 24 weeks. Demographics and disease characteristics were generally similar between patients with 1 week or less and 2 weeks or more of missed MTX. Unemployment, less disability, higher Patient Global scores, and no prior disease‐modifying antirheumatic drug (DMARD) use were associated with correct dosing. No significant differences in adherence were observed between patients receiving concomitant MTX versus MTX monotherapy, and biologic DMARD‐experienced versus biologic DMARD‐naïve patients. Higher scores in BMQ Specific Necessity (indicating a greater belief in the necessity of the medication) was associated with a decreased likelihood of dosing at an interval shorter than prescribed (odds ratio 0.89).

Conclusion

Even in a participatory group over a short period, MTX adherence was suboptimal and associated with certain demographics, medication experience, and beliefs about medicines. This suggests a need for screening and alternative treatment opportunities in nonadherent MTX patients with RA.

Akt phosphorylation of mitochondrial Lonp1 protease enables oxidative metabolism and advanced tumor traits

Tumor mitochondria have heightened protein folding quality control, but the regulators of this process and how they impact cancer traits are not completely understood. Here we show that the ATP-directed mitochondrial protease, LonP1 is upregulated by stress conditions, including hypoxia, in tumor, but not normal cells. In mitochondria, LonP1 is phosphorylated by Akt on Ser173 and Ser181, enhancing its protease activity. Interference with this pathway induces accumulation of misfolded subunits of electron transport chain complex II and complex V, resulting in impaired oxidative bioenergetics and heightened ROS production. Functionally, this suppresses mitochondrial trafficking to the cortical cytoskeleton, shuts off tumor cell migration and invasion, and inhibits primary and metastatic tumor growth, in vivo. These data identify LonP1 as a key effector of mitochondrial reprogramming in cancer and potential therapeutic target.

Myc-mediated transcriptional regulation of the mitochondrial chaperone TRAP1 controls primary and metastatic tumor growth

The role of mitochondria in cancer continues to be debated, and whether exploitation of mitochondrial functions is a general hallmark of malignancy or a tumor- or context-specific response is still unknown. Using a variety of cancer cell lines and several technical approaches, including siRNA-mediated gene silencing, ChIP assays, global metabolomics and focused metabolite analyses, bioenergetics, and cell viability assays, we show that two oncogenic Myc proteins, c-Myc and N-Myc, transcriptionally control the expression of the mitochondrial chaperone TNFR-associated protein-1 (TRAP1) in cancer. In turn, this Myc-mediated regulation preserved the folding and function of mitochondrial oxidative phosphorylation (OXPHOS) complex II and IV subunits, dampened reactive oxygen species production, and enabled oxidative bioenergetics in tumor cells. Of note, we found that genetic or pharmacological targeting of this pathway shuts off tumor cell motility and invasion, kills Myc-expressing cells in a TRAP1-dependent manner, and suppresses primary and metastatic tumor growth in vivo We conclude that exploitation of mitochondrial functions is a general trait of tumorigenesis and that this reliance of cancer cells on mitochondrial OXPHOS pathways could offer an actionable therapeutic target in the clinic.

Nutrition risk and mortality in older oncology patients: An exploratory study

AIM

The primary aim of this analysis was to identify if two standard measures incorporated into the comprehensive geriatric assessment; specifically, malnutrition risk and body mass index (BMI), could predict 12-month mortality in older patients with solid tumours. The secondary aim was to evaluate if malnutrition risk and BMI were associated with chemotherapy outcomes (discontinuation/modification of treatment) in older patients with solid tumours.

METHODS

Older patients (aged ≥70 years) with solid cancers were recruited from the outpatient oncology clinic of a tertiary hospital in Brisbane, Australia. Participants' nutritional parameters, BMI, and malnutrition risk (determined using the Malnutrition Screening Tool (MST)) were recorded at baseline. Mortality data and chemotherapy outcomes were recorded for 12 months.

RESULTS

Seventy-four participants (67% males, median age 77 (±4.4) years) were recruited. Nearly half the cohort was at-risk of malnutrition at baseline (n = 39, 46%). Chemotherapy was prescribed to 39% (n = 29) of the cohort. For patients receiving chemotherapy neither being underweight nor having a low or medium risk of malnutrition was associated with adverse chemotherapy outcomes or 12-month mortality. At a bivariate level, malnutrition risk was significantly associated with 12-month mortality in patients who did not receive chemotherapy (P = 0.018), but not BMI.

CONCLUSIONS

This analysis indicates that malnutrition risk was a potential indicator of 12-month mortality in cases where chemotherapy was considered unfeasible. However, this was not an independent risk factor. Further investigation using a larger sample is required to determine the association between malnutrition risk, quality of life and mortality in patients who are not considered to be fit for chemotherapy.

Syntaphilin Ubiquitination Regulates Mitochondrial Dynamics and Tumor Cell Movements

Syntaphilin (SNPH) inhibits the movement of mitochondria in tumor cells, preventing their accumulation at the cortical cytoskeleton and limiting the bioenergetics of cell motility and invasion. Although this may suppress metastasis, the regulation of the SNPH pathway is not well understood. Using a global proteomics screen, we show that SNPH associates with multiple regulators of ubiquitin-dependent responses and is ubiquitinated by the E3 ligase CHIP (or STUB1) on Lys111 and Lys153 in the microtubule-binding domain. SNPH ubiquitination did not result in protein degradation, but instead anchored SNPH on tubulin to inhibit mitochondrial motility and cycles of organelle fusion and fission, that is dynamics. Expression of ubiquitination-defective SNPH mutant Lys111→Arg or Lys153→Arg increased the speed and distance traveled by mitochondria, repositioned mitochondria to the cortical cytoskeleton, and supported heightened tumor chemotaxis, invasion, and metastasis in vivo Interference with SNPH ubiquitination activated mitochondrial dynamics, resulting in increased recruitment of the fission regulator dynamin-related protein-1 (Drp1) to mitochondria and Drp1-dependent tumor cell motility. These data uncover nondegradative ubiquitination of SNPH as a key regulator of mitochondrial trafficking and tumor cell motility and invasion. In this way, SNPH may function as a unique, ubiquitination-regulated suppressor of metastasis.Significance: These findings reveal a new mechanism of metastasis suppression by establishing the role of SNPH ubiquitination in inhibiting mitochondrial dynamics, chemotaxis, and metastasis. Cancer Res; 78(15); 4215-28. ©2018 AACR.

Malnutrition, poor food intake, and adverse healthcare outcomes in non-critically ill obese acute care hospital patients

BACKGROUND & AIMS

Obesity, defined as a BMI ≥ 30 kg/m², has demonstrated protective associations with mortality in some diseases. However, recent evidence demonstrates that poor nutritional status in critically ill obese patients confounds this relationship. The purpose of this paper is to evaluate if poor nutritional status, poor food intake and adverse health-related outcomes have a demonstrated association in non-critically ill obese acute care hospital patients.

METHODS

This is a secondary analysis of the Australasian Nutrition Care Day Survey dataset (N = 3122), a prospective cohort study conducted in hospitals from Australia and New Zealand in 2010. At baseline, hospital dietitians recorded participants' BMI, evaluated nutritional status using Subjective Global Assessment (SGA), and recorded 24-h food intake (as 0%, 25%, 50%, 75%, and 100% of the offered food). Post-three months, participants' length of stay (LOS), readmissions, and in-hospital mortality data were collected. Bivariate and regression analyses were conducted to investigate if there were an association between BMI, nutritional status, poor food intake, and health-related outcomes.

RESULTS

Of the 3122 participants, 2889 (93%) had eligible data. Obesity was prevalent in 26% of the cohort (n = 750; 75% females; 61 ± 15 years; 37 ± 7 kg/m²). Fourteen percent (n = 105) of the obese patients were malnourished. Over a quarter of the malnourished obese patients (N = 30/105, 28%) consumed ≤25% of the offered meals. Most malnourished obese patients (74/105, 70%) received standard diets without additional nutritional support. After controlling for confounders (age, disease type and severity), malnutrition and intake ≤25% of the offered meals independently trebled the odds of in-hospital mortality within 90 days of hospital admission in obese patients.

CONCLUSION

Although malnourished obese experienced significantly adverse health-related outcomes they were least likely to receive additional nutritional support. This study demonstrates that BMI alone cannot be used as a surrogate measure for nutritional status and warrants routine nutritional screening for all hospital patients, and subsequent nutritional assessment and support for malnourished patients.

An investigation into the nutritional status of patients receiving an Enhanced Recovery After Surgery (ERAS) protocol versus standard care following Oesophagectomy

PURPOSE

Enhanced Recovery After Surgery (ERAS) protocols have been effectively expanded to various surgical specialities including oesophagectomy. Despite nutrition being a key component, actual nutrition outcomes and specific guidelines are lacking. This cohort comparison study aims to compare nutritional status and adherence during implementation of a standardised post-operative nutritional support protocol, as part of ERAS, compared to those who received usual care.

METHODS

Two groups of patients undergoing resection of oesophageal cancer were studied. Group 1 (n = 17) underwent oesophagectomy between Oct 2014 and Nov 2016 during implementation of an ERAS protocol. Patients in group 2 (n = 16) underwent oesophagectomy between Jan 2011 and Dec 2012 prior to the implementation of ERAS. Demographic, nutritional status, dietary intake and adherence data were collected. Ordinal data was analysed using independent t tests, and categorical data using chi-square tests.

RESULTS

There was no significant difference in nutrition status, dietary intake or length of stay following implementation of an ERAS protocol. Malnutrition remained prevalent in both groups at day 42 post surgery (n = 10, 83% usual care; and n = 9, 60% ERAS). A significant difference was demonstrated in adherence with earlier initiation of oral free fluids (p <0.008), transition to soft diet (p <0.004) and continuation of jejunostomy feeds on discharge (p <0.000) for the ERAS group.

CONCLUSION

A standardised post-operative nutrition protocol, within an ERAS framework, results in earlier transition to oral intake; however, malnutrition remains prevalent post surgery. Further large-scale studies are warranted to examine individualised decision-making regarding nutrition support within an ERAS protocol.

Characterization of CDK(5) inhibitor, 20-223 (aka CP668863) for colorectal cancer therapy

Colorectal cancer (CRC) remains one of the leading causes of cancer related deaths in the United States. Currently, there are limited therapeutic options for patients suffering from CRC, none of which focus on the cell signaling mechanisms controlled by the popular kinase family, cyclin dependent kinases (CDKs). Here we evaluate a Pfizer developed compound, CP668863, that inhibits cyclin-dependent kinase 5 (CDK5) in neurodegenerative disorders. CDK5 has been implicated in a number of cancers, most recently as an oncogene in colorectal cancers. Our lab synthesized and characterized CP668863 - now called 20-223. In our established colorectal cancer xenograft model, 20-223 reduced tumor growth and tumor weight indicating its value as a potential anti-CRC agent. We subjected 20-223 to a series of cell-free and cell-based studies to understand the mechanism of its anti-tumor effects. In our hands, in vitro 20-223 is most potent against CDK2 and CDK5. The clinically used CDK inhibitor AT7519 and 20-223 share the aminopyrazole core and we used it to benchmark the 20-223 potency. In CDK5 and CDK2 kinase assays, 20-223 was ∼3.5-fold and ∼65.3-fold more potent than known clinically used CDK inhibitor, AT7519, respectively. Cell-based studies examining phosphorylation of downstream substrates revealed 20-223 inhibits the kinase activity of CDK5 and CDK2 in multiple CRC cell lines. Consistent with CDK5 inhibition, 20-223 inhibited migration of CRC cells in a wound-healing assay. Profiling a panel of CRC cell lines for growth inhibitory effects showed that 20-223 has nanomolar potency across multiple CRC cell lines and was on an average >2-fold more potent than AT7519. Cell cycle analyses in CRC cells revealed that 20-223 phenocopied the effects associated with AT7519. Collectively, these findings suggest that 20-223 exerts anti-tumor effects against CRC by targeting CDK 2/5 and inducing cell cycle arrest. Our studies also indicate that 20-223 is a suitable lead compound for colorectal cancer therapy.

Clinical spectrum and surgical outcomes in spherophakia: a prospective interventional study

PurposeTo study the varied clinical presentations of patients with spherophakia, their management using surgical methods, and the clinical outcomes.Patients and methodsA prospective interventional study of 13 patients of spherophakia who presented to us from January 2014 and were followed up over the course of their treatment, and the data were documented for analysis.ResultsIn all, 26 eyes of 13 patients were reviewed and the median age of presentation was 12±12.05 years. All patients had a bilateral presentation with 22 eyes having lenticular myopia with a mean refractive error of -11.5±12.945 DS. Ten eyes presented with glaucoma of which six had raised intraocular pressure (IOP) >21 mm Hg. A total of 23 eyes underwent lens extraction for dislocation/subluxation. Lens extraction helped lower overall IOP. Refractive rehabilitation was done with ACIOL, posterior chamber intraocular lens (PCIOL) with capsular tension ring, and scleral-fixated intraocular lens (SFIOL) in respective cases with ACIOLs being the most commonly used option.ConclusionsSpherophakia is a rare condition, which exhibits a varying degree of lenticular myopia, glaucoma, and subluxation of the crystalline lens. Lensectomy with proper rehabilitation using ACIOL, PCIOL, or SFIOL is a method of managing subluxation and unacceptable myopia. Lensectomy may also be a viable option of controlling glaucoma alongside medications and glaucoma surgery for the management of glaucoma in such cases.

Modified technique of endocapsular lens aspiration for severely subluxated lenses

PurposeSeverely subluxated crystalline lenses pose a difficult situation to anterior segment surgeons and can only be managed surgically by removal of the lens as well as the capsular bag. Several techniques have been described in literature for the management of such cases. We describe a modified technique of endocapsular lens aspiration by the limbal route for lens extraction through small incisions on the cornea.Patients and methodsThirty-two eyes of 16 consecutive patients with severely subluxated crystalline lenses were recruited in the study. All eyes underwent a modified technique of lens aspiration within the capsular bag using a single instrument, vitrectomy cutter, and irrigation cannula, followed by sacrificing of the capsular bag. The patients were either left aphakic or implanted with an open loop anterior chamber intraocular lens (ACIOL Kelman Multiflex) and prospectively followed up for a period of 3 months.ResultsThe mean age of the patients was 9 years 3 months±3 years (range 5-15 yrs). All eyes underwent complete lens aspiration within the capsular bag with no dislocation of the lens matter. ACIOL was inserted in 22 eyes (68.7%) and 10 eyes (31.2%) were left aphakic. All the surgeries were uneventful. The mean best corrected visual acuity (BCVA) at 3 months post surgery was 0.47±0.11 logMAR which was significantly better than pre-operative BCVA (P=0.001). The percentage endothelial cell loss at 3 months was 7.1%. There was no evidence of glaucoma, corneal decompensation, or retinal detachment. The astigmatism which increased from 1.45D±086 preoperatively to 3.76D±2.02 1 week post-operatively due to sutures reduced to 1.97D±0.81 post suture removal at 3 months.ConclusionThe modified technique of endocapsular lens aspiration proves to be a simple and effective method of removal of the lens-capsular bag complex in severely subluxated lenses.

Dengue Fever Triggering Kawasaki Disease

BACKGROUND

Several bacterial and viral infections are listed as triggering factors for Kawasaki disease; association with dengue fever is rare.

CASE CHARACTERISTICS

A 5-year-old girl who presented with fever that was confirmed to be dengue fever, and subsequently improved, except that the fever persisted. She fulfilled diagnostic criteria for Kawasaki disease on day 7 of fever.

OUTCOME

Child responded satisfactorily to intravenous immunoglobulin administration.

MESSAGE

Kawasaki disease should be kept as one of the probabilities in a case of dengue if fever persists beyond the expected duration.

TGFβ/Smad3 regulates proliferation and apoptosis through IRS-1 inhibition in colon cancer cells

In this study, we have uncovered a novel crosstalk between TGFβ and IGF-1R signaling pathways. We show for the first time that expression and activation of IRS-1, an IGF-1R adaptor protein, is decreased by TGFβ/Smad3 signaling. Loss or attenuation of TGFβ activation leads to elevated expression and phosphorylation of IRS-1 in colon cancer cells, resulting in enhanced cell proliferation, decreased apoptosis and increased tumor growth in vitro and in vivo. Downregulation of IRS-1 expression reversed Smad3 knockdown-mediated oncogenic phenotypes, indicating that TGFβ/Smad3 signaling inhibits cell proliferation and increases apoptosis at least partially through the inhibition of IRS-1 expression and activation. Additionally, the TGFβ/Smad3/IRS-1 signaling axis regulates expression of cyclin D1 and XIAP, which may contribute to TGFβ/Smad3/IRS-1-mediated cell cycle progression and survival. Given that loss of TGFβ signaling occurs frequently in colon cancer, an important implication of our study is that IRS-1 could be a potential therapeutic target for colon cancer treatment.

Abstract 4139: Role of Akt2 in cell survival and metastasis of colorectal cancer (CRC) cells

Background: Colorectal Cancer (CRC) is the second highest cause of cancer related deaths in United States. Metastatic dissemination of CRC cells to distant organs (primarily to the liver and lungs) makes the disease more lethal and incurable. Inappropriate cell survival signaling mechanisms contribute to successful colonization of cells at metastatic sites. Akt is a major cell survival-signaling node, which undergoes aberrant activation in various types of cancer. The Akt family has three members: Akt1, Akt2 and Akt3 which share structural homology and have similar mechanism of activation; however, differences in the phenotype of Akt1, Akt2 and Akt3 knock out mice suggest that they have non-redundant functional characteristics. Recently Akt2 has been identified as a significant contributor to colon cancer malignancy in addition to Akt1. Earlier reports have shown that knockdown of Akt2 results in reduced liver metastasis of CRC cells, however there are no studies related to the mechanism responsible for the reduction in metastasis.

We observed a significant increase in the expression of Akt2 (microarray analysis) in liver metastatic samples formed by highly metastatic IGF1R-dependent CRC cells in comparison to the primary tumor. This was further confirmed by western blot and immunohistochemistry (IHC) analysis. Additionally, correlative studies using human primary colon carcinoma and corresponding liver metastatic samples showed a significant (p&lt;0.001) increase in the expression of Akt2. These preliminary data led us to hypothesize that Akt2 may be playing a role in regulating cell survival and metastasis of CRC cells.

Materials and Methods: IGF1R-dependent CRC cells (GEO and CBS) were used for the study. Two doxycycline inducible shRNAs for Akt2 were introduced by lentiviral transfection. Non-Targeting shRNA was used as control.

Results: shRNA-mediated knockdown of Akt2 led to reduction in the expression of XIAP and survivin. We and others have shown that these IAPs (XIAP and survivin) are implicated to play an important role in cancer cell survival and metastasis. Furthermore, loss of Akt2 resulted in loss of pBad (S136), which is an essential cell survival marker. Loss of pBad results in increased cell death by PARP activation. Akt2 knockdown also affects cell survival by increasing p21 and decreasing the expression of cyclin E. PCR array analysis for metastatic genes revealed that a metastatic suppressor gene MTSS1 was 9 fold increased on knockdown of Akt2. It has been shown that MTSS1 inhibits metastasis by affecting cell junction assembly and stability.

Conclusion: We have shown that loss of Akt2 promotes cell death and inhibits cell proliferation. This is the first study, which suggests the mechanism of Akt2 mediated cell death by XIAP and survivin downregulation. These results suggest that Akt2 inhibits metastasis by increasing the expression of MTSS1.

Citation Format: Ekta Agarwal. Role of Akt2 in cell survival and metastasis of colorectal cancer (CRC) cells. [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 4139. doi:10.1158/1538-7445.AM2015-4139

Ezrin expression and cell survival regulation in colorectal cancer

Colorectal cancer (CRC) is the second largest cause of cancer deaths in the United States. A key barrier that prevents better outcomes for this type of cancer as well as other solid tumors is the lack of effective therapies against the metastatic disease. Thus there is an urgent need to fill this gap in cancer therapy. We utilized a 2D-DIGE proteomics approach to identify and characterize proteins that are differentially regulated between primary colon tumor and liver metastatic deposits of the IGF1R-dependent GEO human CRC xenograft, orthotopically implanted in athymic nude mice that may serve as potential therapeutic targets against CRC metastasis. We observed increased expression of ezrin in liver metastasis in comparison to the primary colonic tumor. Increased ezrin expression was further confirmed by western blot and microarray analyses. Ezrin, a cytoskeletal protein belonging to Ezrin-Radixin-Moesin (ERM) family plays important roles in cell motility, invasion and metastasis. However, its exact function in colorectal cancer is not well characterized. Establishment of advanced GEO cell lines with enhanced liver-metastasizing ability showed a significant increase in ezrin expression in liver metastasis. Increased phosphorylation of ezrin at the T567 site (termed here as p-ezrin T567) was observed in liver metastasis. IHC studies of human CRC patient specimens showed an increased expression of p-ezrin T567 in liver metastasis compared to the primary tumors of the same patient. Ezrin modulation by siRNA, inhibitors and T567A/D point mutations significantly downregulated inhibitors of apoptosis (IAP) proteins XIAP and survivin that have been linked to increased aberrant cell survival and metastasis and increased cell death. Inhibition of the IGF1R signaling pathway by humanized recombinant IGF1R monoclonal antibody MK-0646 in athymic mouse subcutaneous xenografts resulted in inhibition of p-ezrin T567 indicating ezrin signaling is downstream of the IGF1R signaling pathway. We identified increased expression of p-ezrin T567 in CRC liver metastasis in both orthotopically implanted GEO tumors as well as human patient specimens. We report for the first time that p-ezrin T567 is downstream of the IGF1R signaling and demonstrate that ezrin regulates cell survival through survivin/XIAP modulation.

Akt inhibitor MK-2206 promotes anti-tumor activity and cell death by modulation of AIF and Ezrin in colorectal cancer

BACKGROUND

There is extensive evidence for the role of aberrant cell survival signaling mechanisms in cancer progression and metastasis. Akt is a major component of cell survival-signaling mechanisms in several types of cancer. It has been shown that activated Akt stabilizes XIAP by S87 phosphorylation leading to survivin/XIAP complex formation, caspase inhibition and cytoprotection of cancer cells. We have reported that TGFβ/PKA/PP2A-mediated tumor suppressor signaling regulates Akt phosphorylation in association with the dissociation of survivin/XIAP complexes leading to inhibition of stress-dependent induction of cell survival.

METHODS

IGF1R-dependent colon cancer cells (GEO and CBS) were used for the study. Effects on cell proliferation and cell death were determined in the presence of MK-2206. Xenograft studies were performed to determine the effect of MK-2206 on tumor volume. The effect on various cell death markers such as XIAP, survivin, AIF, Ezrin, pEzrin was determined by western blot analysis. Graph pad 5.0 was used for statistical analysis. P < 0.05 was considered significant.

RESULTS

We characterized the mechanisms by which a novel Akt kinase inhibitor MK-2206 induced cell death in IGF1R-dependent colorectal cancer (CRC) cells with upregulated PI3K/Akt signaling in response to IGF1R activation. MK-2206 treatment generated a significant reduction in tumor growth in vivo and promoted cell death through two mechanisms. This is the first report demonstrating that Akt inactivation by MK-2206 leads to induction of and mitochondria-to-nuclear localization of the Apoptosis Inducing Factor (AIF), which is involved in caspase-independent cell death. We also observed that exposure to MK-2206 dephosphorylated Ezrin at the T567 site leading to the disruption of Akt-pEzrin-XIAP cell survival signaling. Ezrin phosphorylation at this site has been associated with malignant progression in solid tumors.

CONCLUSION

The identification of these 2 novel mechanisms leading to induction of cell death indicates MK-2206 might be a potential clinical candidate for therapeutic targeting of the subset of IGF1R-dependent cancers in CRC.

In vivo analysis of insulin-like growth factor type 1 receptor humanized monoclonal antibody MK-0646 and small molecule kinase inhibitor OSI-906 in colorectal cancer

The development and characterization of effective anticancer drugs against colorectal cancer (CRC) is of urgent need since it is the second most common cause of cancer death. The study was designed to evaluate the effects of two IGF-1R antagonists, MK-0646, a recombinant fully humanized monoclonal antibody and OSI-906, a small molecule tyrosine kinase inhibitor on CRC cells. Xenograft study was performed on IGF-1R-dependent CRC cell lines for analyzing the antitumor activity of MK-0646 and OSI-906. Tumor proliferation and apoptosis were assessed using Ki67 and TUNEL assays, respectively. We also performed in vitro characterization of MK-0646 and OSI-906 treatment on CRC cells to identify mechanisms associated with drug-induced cell death. Exposure of the GEO and CBS tumor xenografts to MK-0646 or OSI-906 led to a decrease in tumor growth. TUNEL analysis showed an increase of approximately 45-55% in apoptotic cells in both MK-0646 and OSI-906 treated tumor samples. We report the novel finding that treatment with IGF-1R antagonists led to downregulation of X-linked inhibitor of apoptosis (XIAP) protein involved in cell survival and inhibition of cell death. In conclusion, IGF-1R antagonists (MK-0646 and OSI-906) demonstrated single agent inhibition of subcutaneous CRC xenograft growth. This was coupled to pro-apoptotic effects resulting in downregulation of XIAP and inhibition of cell survival. We report a novel mechanism by which MK-0646 and OSI-906 elicits cell death in vivo and in vitro. Moreover, these results indicate that MK-0646 and OSI-906 may be potential anticancer candidates for the treatment of patients with IGF-1R-dependent CRC.

An exploratory study to evaluate whether medical nutrition therapy can improve dietary intake in hospital patients who eat poorly

BACKGROUND

The Australasian Nutrition Care Day Survey (ANCDS) reported that two-fifths of patients consume ≤50% of the offered food in Australian and New Zealand hospitals. After controlling for confounders (nutritional status, age, disease type and severity), the ANCDS also established an independent association between poor food intake and increased in-hospital mortality. The present study aimed to evaluate whether medical nutrition therapy (MNT) could improve dietary intake in hospital patients eating poorly.

METHODS

An exploratory pilot study was conducted in the respiratory, neurology and orthopaedic wards of an Australian hospital. At baseline, percentage food intake (0%, 25%, 50%, 75% and 100%) was evaluated for each main meal and snack for a 24-h period in patients hospitalised for ≥2 days and not under dietetic review. Patients consuming ≤50% of offered meals as a result of nutrition-impact symptoms were referred to ward dietitians for MNT. Food intake was re-evaluated on the seventh day after recruitment (post-MNT).

RESULTS

One hundred and eighty-four patients were observed over 4 weeks; 32 patients were referred for MNT. Although baseline and post-MNT data for 20 participants [mean (SD) age 68 (17) years, 65% females] indicated a significant increase in median energy and protein intake post-MNT (3600 kJ day(-1) ; 40 g day(-1) ) versus baseline (2250 kJ day(-1) ; 25 g day(-1) ) (P < 0.05), the increased intake met only 50% of dietary requirements. Persistent nutrition impact symptoms affected intake.

CONCLUSIONS

In the present pilot study, although dietary intake improved, it remained inadequate to meet participants' estimated requirements as a result of ongoing nutrition-impact symptoms. Appropriate medical management and early enteral feeding could be a possible solution for such patients.

Differential PKA activation and AKAP association determines cell fate in cancer cells

BACKGROUND

The dependence of malignant properties of colorectal cancer (CRC) cells on IGF1R signaling has been demonstrated and several IGF1R antagonists are currently in clinical trials. Recently, we identified a novel pathway in which cAMP independent PKA activation by TGFβ signaling resulted in the destabilization of survivin/XIAP complex leading to increased cell death. In this study, we evaluated the effect of IGF1R inhibition or activation on PKA activation and its downstream cell survival signaling mechanisms.

METHODS

Small molecule IGF1R kinase inhibitor OSI-906 was used to test the effect of IGF1R inhibition on PKA activation, AKAP association and its downstream cell survival signaling. In a complementary approach, ligand mediated activation of IGF1R was performed and AKAP/PKA signaling was analyzed for their downstream survival effects.

RESULTS

We demonstrate that the inhibition of IGF1R in the IGF1R-dependent CRC subset generates cell death through a novel mechanism involving TGFβ stimulated cAMP independent PKA activity that leads to disruption of cell survival by survivin/XIAP mediated inhibition of caspase activity. Importantly, ligand mediated activation of the IGF1R in CRC cells results in the generation of cAMP dependent PKA activity that functions in cell survival by inhibiting caspase activity. Therefore, this subset of CRC demonstrates 2 opposing pathways organized by 2 different AKAPs in the cytoplasm that both utilize activation of PKA in a manner that leads to different outcomes with respect to life and death. The cAMP independent PKA activation pathway is dependent upon mitochondrial AKAP149 for its apoptotic functions. In contrast, Praja2 (Pja2), an AKAP-like E3 ligase protein was identified as a key element in controlling cAMP dependent PKA activity and pro-survival signaling. Genetic manipulation of AKAP149 and Praja2 using siRNA KD had opposing effects on PKA activity and survivin/XIAP regulation.

CONCLUSIONS

We had identified 2 cytoplasmic pathways dependent upon the same enzymatic activity with opposite effects on cell fate in terms of life and death. Understanding the specific mechanistic functions of IGF1R with respect to determining the PKA survival functions would have potential for impact upon the development of new therapeutic strategies by exploiting the IGF1R/cAMP-PKA survival signaling in cancer.

Cell survival and metastasis regulation by Akt signaling in colorectal cancer

Dissemination of cancer cells to distant organ sites is the leading cause of death due to treatment failure in different types of cancer. Mehlen and Puisieux have reviewed the importance of the development of inappropriate cell survival signaling for various steps in the metastatic process and have noted the particular importance of aberrant cell survival to successful colonization at the metastatic site. Therefore, the understanding of mechanisms that govern cell survival fate of these metastatic cells could lead to the understanding of a new paradigm for the control of metastatic potential and could provide the basis for developing novel strategies for the treatment of metastases. Numerous studies have documented the widespread role of Akt in cell survival and metastasis in colorectal cancer, as well as many other types of cancer. Akt acts as a key signaling node that bridges the link between oncogenic receptors to many essential pro-survival cellular functions, and is perhaps the most commonly activated signaling pathway in human cancer. In recent years, Akt2 and Akt3 have emerged as significant contributors to malignancy alongside the well-characterized Akt1 isoform, with distinct non-overlapping functions. This review is aimed at gaining a better understanding of the Akt-driven cell survival mechanisms that contribute to cancer progression and metastasis and the pharmacological inhibitors in clinical trials designed to counter the Akt-driven cell survival responses in cancer.

Abstract 594: Dual regulation of cell death by Akt kinase inhibitor Mk-2206 in colorectal cancer

Background: Colorectal cancer (CRC) is the second highest cause of cancer related deaths in the United States. Dissemination of CRC cells to distant organs (liver and lungs) often leads to treatment failure. Thus, the identification of novel strategies for the treatment of metastases is a pressing need in this type of cancer. Several reports have suggested the development of inappropriate cell survival signaling for various steps in the metastatic process and have noted the particular importance of aberrant cell survival to successful colonization at metastatic sites. We have earlier reported that Akt inactivation is associated with survivin and XIAP downregulation and increased cell death. Given the widespread role of Akt in cell survival and association of survivin and XIAP with CRC progression and metastasis, as well as other types of cancer, we hypothesize that Akt phosphorylation may be key to the aberrant survival mechanism permitting metastatic growth at distal organ sites. Thus, inactivation of Akt activity might be an important therapeutic target in CRC metastasis.

Methods: Mk-2206 is a potent allosteric kinase inhibitor of Akt (provided by Merck). It inhibits the translocation of Akt to plasma membrane to prevent its phosphorylation and activation. IGF1R dependent CRC cell lines were treated with MK-2206 to study its anti-tumor effects in vitro and in vivo.

Results: Mk-2206 promotes anti-tumor activity in the IGF1R dependent CRC cell lines and increases cell death both in vitro and in vivo. Mk-2206 inhibits Akt phosphorylation at S473 and T308 leading to decreased protein expression of XIAP and Survivin. Interestingly, Mk-2206 treatment upregulated apoptosis inducing factor (AIF) and its translocation from mitochondria to the nucleus and a concomitant inactivation of phospho-Ezrin at Y354 and T567.Ezrin is a cytoskeleton organizing protein implicated in the metastatic process of several other types of cancer in addition to CRC. RNAi studies were performed to confirm the role of AIF and Ezrin in Mk-2206 mediated cell death. We are currently analyzing the anti-metastatic effects of MK-2206 in an orthotopic mouse model of human CRC cells.

Conclusion: In this work we have demonstrated the effectiveness of Mk-2206 as a pharmacological agent for targeting CRC cells. We have identified dual mechanisms by which Mk-2206-mediated Akt inactivation promotes cell death.The first mechanism involved caspase-independent AIF mediated DNA fragmentation; while the second involved caspase-dependent Akt-Ezrin-XIAP mediated cell death.

Citation Format: Ekta Agarwal, Anathbandhu Chaudhuri, Michael G. Brattain, Sanjib Chowdhury. Dual regulation of cell death by Akt kinase inhibitor Mk-2206 in colorectal cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 594. doi:10.1158/1538-7445.AM2013-594

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.

Clinical and microbiologic effects of commercially available gel and powder containing Acacia arabica on gingivitis

BACKGROUND

There is a need for an anti-plaque agent that can be used on a daily basis without the side effects of antibacterial chemicals such as chlorhexidine. The present study was designed to evaluate the clinical and microbiologic effects of commercially available gel and powder containing Acacia arabica in subjects with gingivitis.

METHODS

One hundred and twenty subjects with chronic generalized gingivitis were selected and randomly divided into four groups: Group 1 - placebo group; Group 2 -Acacia arabica gel group; Group 3 -Acacia arabica powder group; and Group 4 - 1% chlorhexidine gel group. Microbial counts of plaque samples, the gingival index of Loe and Silness and the plaque index were evaluated at baseline, 6 weeks, 12 weeks and 24 weeks. Microbial counts of plaque samples were evaluated at all visits.

RESULTS

Acacia arabica gel and powder showed significant clinical improvement in gingival and plaque index scores as compared to a placebo. This improvement was comparable to 1% chlorhexidine gel. The difference between gel and powder with regard to clinical and microbiological parameters was not found to be significant at any time interval.

CONCLUSIONS

Both Acacia arabica gel and powder may be useful herbal formulations for chemical plaque control in subjects with gingivitis.