The PP4R1 sub-unit of protein phosphatase PP4 is essential for inhibition of NF-κB by merkel polyomavirus small tumour antigen

Merkel cell carcinoma (MCC) is a highly aggressive skin cancer with a high metastatic potential. The majority of MCC cases are caused by the Merkel cell polyomavirus (MCPyV), through expression of the virus-encoded tumour antigens. Whilst mechanisms attributing tumour antigen expression to transformation are being uncovered, little is known of the mechanisms by which MCPyV persists in the host. We previously identified the MCPyV small T antigen (tAg) as a novel inhibitor of nuclear factor kappa B (NF-kB) signalling and a modulator of the host anti-viral response. Here we demonstrate that regulation of NF-kB activation involves a previously undocumented interaction between tAg and regulatory sub-unit 1 of protein phosphatase 4 (PP4R1). Formation of a complex with PP4R1 and PP4c is required to bridge MCPyV tAg to the NEMO adaptor protein, allowing deactivation of the NF-kB pathway. Mutations in MCPyV tAg that fail to interact with components of this complex, or siRNA depletion of PP4R1, prevents tAg-mediated inhibition of NF-kB and pro-inflammatory cytokine production. Comparison of tAg binding partners from other human polyomavirus demonstrates that interactions with NEMO and PP4R1 are unique to MCPyV. Collectively, these data identify PP4R1 as a novel target for virus subversion of the host anti-viral response.

Transarterial Chemoembolization within First 3 Months of Sorafenib Initiation Improves Overall Survival in Hepatocellular Carcinoma: A Retrospective, Multi-Institutional Study with Propensity Matching

PURPOSE

The impact of transarterial chemoembolization after initiation of sorafenib (SOR) has not been prospectively compared with SOR alone in unresectable hepatocellular carcinoma (HCC). The objective of this study was to assess whether SOR + transarterial chemoembolization provides benefit over SOR alone in this setting.

MATERIALS AND METHODS

A retrospective cohort study with propensity matching using data from patients prescribed SOR for HCC at Veterans Health Administration hospitals from 2007 to 2015. The primary outcome was overall survival from the time of SOR prescription and stratified by receipt of transarterial chemoembolization within 90 days of SOR initiation.

RESULTS

A total of 4,896 patients received SOR for HCC, of whom 232 (4.7%) underwent transarterial chemoembolization within 90 days. Patients receiving transarterial chemoembolization + SOR were highly selected, being younger and with less significant hepatic dysfunction, earlier Barcelona Clinic Liver Cancer stage (P < .0001), and fewer tumors with lower rates of macrovascular invasion (MVI) and metastases (all P < .0001) than SOR-alone patients. In unadjusted analysis, SOR + transarterial chemoembolization was associated with reduced mortality (hazard ratio [HR] 0.61, 95% confidence interval [CI] 0.53-0.71; P < .0001). After propensity matching, SOR + transarterial chemoembolization continued to show significant associations with reduced mortality with HR 0.75 (95% CI 0.62-0.92; P = .0005). Subgroup analysis suggests that the addition of transarterial chemoembolization to SOR improves outcomes in most patients, particularly those with Model for End-Stage Liver Disease score <15, platelets >50,000/μL, and >3 tumors with or without macrovascular invasion, without local invasion or metastases.

CONCLUSIONS

Patients with unresectable HCC started on systemic therapy with SOR appear to benefit from adjuvant transarterial chemoembolization. Optimal application of multimodal therapy in this setting should be prospectively investigated.

Abstract P4-10-14: Pilot data from the development of the Senior Women's Breast Cancer Clinic at Sunnybrook Odette Cancer Centre

Introduction: Women over 70 are a growing demographic of breast cancer patients with specific needs requiring individualized care plans. We developed the interdisciplinary Senior Women's Breast Cancer Clinic (SWBCC) to improve access to a comprehensive geriatric assessment (CGA) and allied health services such as social work, occupational therapy, and pharmacy assistance. After initiation of the SWBCC, we conducted a pilot study using the VES-13 (vulnerable elders survey-13) tool to screen all patients over 70 with the goal of focusing referrals for patients who may benefit most from a CGA. The VES-13 was developed for community-dwelling elders and is validated in oncology patients. The objective of this study is to examine the outcomes of VES-13 screening, determine the medical issues identified by the CGA, and describe the development of this clinic.

Methods: A retrospective review of the clinic from May 2015 - May 2017 was performed using the electronic medical records and paper screening forms. We separately describe the impact of the VES-13 to manage CGA referrals. A score of 3 or greater is a positive screen, and indicates the patient is at risk for death or decline. Non-parametric descriptive statistics were used for statistical analyses.

Results: A total of 25 patients have been seen in the SWBCC for CGA to date. Median age was 83, (range 67-97). A median of two (range 1-4) new medical issues were identified from the CGA for each patient. The most common new diagnoses or issues identified were cognitive impairment (15/25), falls (6/25), neuropathy (4/25), and pain (4/25). The geriatric day program and falls prevention program were common referrals. After the introduction of VES-13 screening, a total of 54 patients were screened. Median age in that group was 78.5 years (range 70-95). The median VES-13 score was 1 (range 0-10). Of the 21 patients screened positive on VES-13, 7 went on to have a CGA. Of the remaining screen-positive patients, 3/21 patients declined SWBCC referral, and the others were not referred at the discretion of the physician. None of the patients with negative VES-13 were referred for CGA. The SWBCC structure was developed to utilize breast cancer-specific resources, whereby geriatricians provide consultation within the oncology space, and the allied health providers were affiliated with the breast centre. Oncology and geriatric administrative staff organized bookings to better coordinate schedules between the two disciplines. The geriatricians supervised trainees for the CGA, and follow-ups took place at SWBCC or in the geriatric outpatient clinic. Clinic coordinators affixed the VES-13 tool to all new patient charts for those aged ≥70. Nursing resources were dedicated to assist patients with VES-13 if needed, and document scores in the electronic medical record.

Conclusions: A dedicated clinic for seniors with breast cancer providing geriatric assessment can identify important undiagnosed medical issues that warrant intervention or monitoring during breast cancer treatment. The VES-13 screening tool provides useful information to help manage resources for geriatrics referral. A prospective trial examining the role of CGA in decision-making for adjuvant chemotherapy is underway in this clinic.

Citation Format: Menjak IB, Trudeau ME, Mehta R, McCullock F, Bristow B, Wright F, Rice K, Gibson L, Pasetka M, Szumacher EF. Pilot data from the development of the Senior Women's Breast Cancer Clinic at Sunnybrook Odette Cancer Centre [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-10-14.

Healthcare Costs Related to Treatment of Hepatocellular Carcinoma Among Veterans With Cirrhosis in the United States

BACKGROUND & AIMS

It is important to quantify medical costs associated with hepatocellular carcinoma (HCC), the incidence of which is rapidly increasing in the United States, for development of rational healthcare policies related to liver cancer surveillance and treatment of chronic liver disease. We aimed to comprehensively quantify healthcare costs for HCC among patients with cirrhosis in an integrated health system and develop a model for predicting costs that is based on clinically relevant variables.

METHODS

Three years subsequent to liver cancer diagnosis, costs accrued by patients included in the Veteran's Outcome and Cost Associated with Liver disease cohort were compiled by using the Department of Veterans Affairs Corporate Data Warehouse. The cohort includes all patients with HCC diagnosed in 2008-2010 within the VA with 100% chart confirmation as well as chart abstraction of tumor and clinical characteristics. Cancer cases were matched 1:4 with non-cancer cirrhosis controls on the basis of severity of liver disease, age, and comorbidities to estimate background cirrhosis-related costs. Univariable and multivariable generalized linear models were developed and used to predict cancer-related overall cost.

RESULTS

Our analysis included 3188 cases of HCC and 12,722 controls. The mean 3-year total cost of care in HCC patients was $154,688 (standard error, $150,953-$158,422) compared with $69,010 (standard error, $67,344-$70,675) in matched cirrhotic controls, yielding an incremental cost of $85,679; 64.9% of this value reflected increased inpatient costs. In univariable analyses, receipt of transplantation, Barcelona Clinic Liver Cancer (BCLC) stage, liver disease etiology, hospital academic affiliation, use of multidisciplinary tumor board, and identification through surveillance were associated with cancer-related costs. Multivariable generalized linear models incorporating transplantation status, BCLC stage, and multidisciplinary tumor board presentation accurately predicted liver cancer-related costs (Hosmer-Lemeshow goodness of fit; P value ≅ 1.0).

CONCLUSIONS

In a model developed to comprehensively quantify healthcare costs for HCC among patients with cirrhosis in an integrated health system, we associated receipt of liver transplantation, BCLC stage, and multidisciplinary tumor board with higher costs. Models that predict total costs on the basis of receipt of liver transplantation were constructed and can be used to model cost-effectiveness of therapies focused on HCC prevention.

Sorafenib prescribed by gastroenterologists and hepatologists for hepatocellular carcinoma: A retrospective, multi-institutional cohort study

Sorafenib is the only Food and Drug Administration (FDA)-approved first-line therapy shown to have survival benefit for patients with advanced hepatocellular carcinoma (HCC). Patients with advanced HCC are often but not exclusively transferred from non-oncologists to oncologists to initiate systemic therapy. The objective of this study was to assess whether sorafenib prescribing by non-oncologists has any impact on utilization, adverse effects, cost or outcome.This was a retrospective cohort study utilizing data from patients prescribed sorafenib for HCC within Veterans Health Administration hospitals with 100% chart abstraction to confirm HCC diagnosis, identify prescribing provider specialty (oncology versus gastroenterology/hepatology), and obtain data required for cancer staging by the Barcelona Clinic Liver Cancer (BCLC) system. The primary outcome was overall survival from the time of sorafenib prescription.A total of 4903 patients who prescribed sorafenib for HCC were identified, for whom 340 patients (6.9%) were prescribed drug by a non-oncologist (Onc). BCLC Stage, age, Child-Turcotte-Pugh score, and comorbidity indices were similar between patients prescribed sorafenib by oncologists and non-oncologists. Oncologists more often discontinued sorafenib due to progression, whereas non-oncologists were more likely to continue sorafenib until death resulting in greater pill utilization and cost. Overall survival in both unadjusted and multivariable models showed no significant impact of prescriber type on survival (222 vs 217 days, P = .96), confirmed with propensity-matched subcohorts.Similar survival outcomes were observed for patients with HCC prescribed sorafenib by non-oncologists and oncologists, suggesting that non-oncologists with expertise in the management of HCC can safely and effectively administer sorafenib.

Mexican consensus on lysosomal acid lipase deficiency diagnosis

INTRODUCTION

Lysosomal acid lipase deficiency (LAL-D) causes progressive cholesteryl ester and triglyceride accumulation in the lysosomes of hepatocytes and monocyte-macrophage system cells, resulting in a systemic disease with various manifestations that may go unnoticed. It is indispensable to recognize the deficiency, which can present in patients at any age, so that specific treatment can be given. The aim of the present review was to offer a guide for physicians in understanding the fundamental diagnostic aspects of LAL-D, to successfully aid in its identification.

METHODS

The review was designed by a group of Mexican experts and is presented as an orienting algorithm for the pediatrician, internist, gastroenterologist, endocrinologist, geneticist, pathologist, radiologist, and other specialists that could come across this disease in their patients. An up-to-date review of the literature in relation to the clinical manifestations of LAL-D and its diagnosis was performed. The statements were formulated based on said review and were then voted upon. The structured quantitative method employed for reaching consensus was the nominal group technique.

RESULTS

A practical algorithm of the diagnostic process in LAL-D patients was proposed, based on clinical and laboratory data indicative of the disease and in accordance with the consensus established for each recommendation.

CONCLUSION

The algorithm provides a sequence of clinical actions from different studies for optimizing the diagnostic process of patients suspected of having LAL-D.

Racial and Ethnic Disparities in Oncotype DX Test Receipt in a Statewide Population-Based Study

Background: Racial disparities have been reported in breast cancer care, yet little is known about disparities in access to gene expression profiling (GEP) tests. Given the impact of GEP test results, such as those of Oncotype DX (ODx), on treatment decision-making for hormone receptor-positive (HR+) breast cancer, it is particularly important to assess disparities in its use. Methods: We conducted a retrospective population-based study of 8,784 patients diagnosed with breast cancer in Connecticut during 2011 through 2013. We assessed the association between race, ethnicity, and ODx receipt among women with HR+ breast cancer for whom NCCN does and does not recommend ODx testing, using bivariate and multivariate logistic analyses. Results: We identified 5,294 women who met study inclusion criteria: 83.8% were white, 6.3% black, and 7.4% Hispanic. Overall, 50.9% (n=4,131) of women in the guideline-recommended group received ODx testing compared with 18.5% (n=1,163) in the nonrecommended group. More white women received the ODx test compared with black and Hispanic women in the recommended and nonrecommended groups (51.4% vs 44.6% and 47.7%; and 21.2% vs 9.0% and 9.7%, respectively). After adjusting for tumor and clinical characteristics, we observed significantly lower ODx use among black (odds ratio [OR], 0.64; 95% CI, 0.47-0.88) and Hispanic women (OR, 0.59; 95% CI, 0.45-0.77) compared with white women in the recommended group and in the guideline-discordant group (blacks: OR, 0.39; 95% CI, 0.20-0.78, and Hispanics: OR, 0.44; 95% CI, 0.23-0.85). Conclusions: In this population-based study, we identified racial disparities in ODx testing. Disparities in access to innovative cancer care technologies may further exacerbate existing disparities in breast cancer outcomes.

Starting Dose of Sorafenib for the Treatment of Hepatocellular Carcinoma: A Retrospective, Multi-Institutional Study

Purpose Sorafenib is currently the only Food and Drug Administration-approved first-line therapy for patients with advanced hepatocellular carcinoma. There are few data examining how sorafenib starting dose may influence patient outcomes and costs. Patients and Methods We retrospectively evaluated 4,903 patients from 128 Veterans Health Administration hospitals who were prescribed sorafenib for hepatocellular carcinoma between January 2006 and April 2015. After 1:1 propensity score matching to account for potential treatment bias, hazard ratios (HRs) were calculated using Cox regression and were tested against a noninferiority margin of HR = 1.1. A matched multivariate logistic regression was performed to adjust for potential confounders. The primary end point was overall survival (OS) of patients who were prescribed standard starting dosage sorafenib (800 mg/d per os) versus that of patients who were prescribed reduced starting dose sorafenib (< 800 mg/d per os). Results There were 3,094 standard dose sorafenib patients (63%) and 1,809 reduced starting dose sorafenib patients (37%). Reduced starting dose sorafenib patients had more Barcelona Clinic Liver Cancer stage D ( P < .001), higher Model for End-Stage Liver Disease Sodium scores ( P < .001), higher Child-Turcotte-Pugh scores ( P < .001), and higher Cirrhosis Comorbidity Index scores ( P = .01). Consequently, reduced starting dose sorafenib patients had lower OS (median, 200 v 233 days, HR = 1.10). After propensity score matching and adjusting for potential confounders, there was no longer a significant OS difference (adjusted hazard ratio [HR_adj], 0.92; 95% CI, 0.83 to 1.01), and this fell significantly below the noninferiority margin ( P < .001). Reduced starting dose sorafenib patients experienced significantly lower total cumulative sorafenib cost and were less likely to discontinue sorafenib because of gastrointestinal adverse effects (8.7% v 10.8%; P = .047). Conclusion The initiation of sorafenib therapy at reduced dosages was associated with reduced pill burden, reduced treatment costs, and a trend toward a decreased rate of discontinuing sorafenib because of adverse events. Reduced dosing was not associated with inferior OS relative to standard dosing.

Association of Provider Specialty and Multidisciplinary Care With Hepatocellular Carcinoma Treatment and Mortality

BACKGROUND & AIMS

Little is known about provider and health system factors that affect receipt of active therapy and outcomes of patients with hepatocellular carcinoma (HCC). We investigated patient, provider, and health system factors associated with receipt of active HCC therapy and overall survival.

METHODS

We performed a national, retrospective cohort study of all patients diagnosed with HCC from January 1, 2008 through December 31, 2010 (n = 3988) and followed through December 31 2014 who received care through the Veterans Administration (128 centers). Outcomes were receipt of active HCC therapy (liver transplantation, resection, local ablation, transarterial therapy, or sorafenib) and overall survival.

RESULTS

In adjusted analyses, receiving care at an academically affiliated Veterans Administration hospital (odds ratio [OR], 1.97; 95% confidence interval [CI], 1.60-2.41) or a multi-specialist evaluation (OR, 1.60; 95% CI, 1.15-2.21), but not review by a multidisciplinary tumor board (OR, 1.19; 95% CI, 0.98-1.46), was associated with a higher likelihood of receiving active HCC therapy. In time-varying Cox proportional hazards models, liver transplantation (hazard ratio [HR], 0.22; 95% CI, 0.16-0.31), liver resection (HR, 0.38; 95% CI, 0.28-0.52), ablative therapy (HR, 0.63; 95% CI, 0.52-0.76), and transarterial therapy (HR, 0.83; 95% CI, 0.74-0.92) were associated with reduced mortality. Subspecialist care by hepatologists (HR, 0.70; 95% CI, 0.63-0.78), medical oncologists (HR, 0.82; 95% CI, 0.74-0.91), or surgeons (HR, 0.79; 95% CI, 0.71-0.89) within 30 days of HCC diagnosis, and review by a multidisciplinary tumor board (HR, 0.83; 95% CI, 0.77-0.90), were associated with reduced mortality.

CONCLUSIONS

In a retrospective cohort study of almost 4000 patients with HCC cared for at VA centers, geographic, provider, and system differences in receipt of active HCC therapy are associated with patient survival. Multidisciplinary methods of care delivery for HCC should be prospectively evaluated and standardized to improve access to HCC therapy and optimize outcomes.

Sofosbuvir plus ribavirin in treatment-naïve patients with chronic hepatitis C virus genotype 1 or 3 infection in India

Until 2014, pegylated interferon plus ribavirin was the recommended standard of care for the treatment of chronic hepatitis C virus (HCV) infection in India. This open-label phase 3b study, conducted across 14 sites in India between 31 March 2014 and 30 November 2015, evaluated the efficacy and safety of sofosbuvir plus ribavirin therapy among treatment-naïve patients with chronic genotype 1 or 3 HCV infection. A total of 117 patients with genotype 1 or 3 HCV infection were randomized 1:1 to receive sofosbuvir 400 mg and weight-based ribavirin (1000 or 1200 mg) daily for 16 or 24 weeks. Among those with genotype 1 infection, the primary efficacy endpoint of sustained virologic response at 12 weeks post-treatment (SVR12) was reported in 90% (95% confidence intervals [CI], 73-98) and 96% (95% CI, 82-100) of patients following 16 and 24 weeks of treatment, respectively. For patients with genotype 3 infection, SVR12 rates were 100% (95% CI, 88-100) and 93% (95% CI, 78-99) after 16 and 24 weeks of therapy, respectively. Adverse events, most of which were mild or moderate in severity, occurred in 69% and 57% of patients receiving 16 and 24 weeks of treatment, respectively. The most common treatment-emergent adverse events were asthenia, headache and cough. Only one patient in the 24-week group discontinued treatment with sofosbuvir during this study. Overall, sofosbuvir plus ribavirin therapy achieved SVR12 rates ≥90% and was well tolerated among treatment-naïve patients with chronic genotype 1 or 3 HCV infection in India.

Identifying barriers to hepatocellular carcinoma surveillance in a national sample of patients with cirrhosis

Hepatocellular carcinoma (HCC) is a leading cause of morbidity and mortality in cirrhosis patients. This provides an opportunity to target the highest-risk population, yet surveillance rates in the United States and Europe range from 10% to 40%. The goal of this study was to identify barriers to HCC surveillance, using data from the Veterans Health Administration, the largest provider of liver-related health care in the United States. We included all patients 75 years of age or younger who were diagnosed with cirrhosis from January 1, 2008, until December 31, 2010. The primary outcome was a continuous measure of the percentage of time up-to-date with HCC surveillance (PTUDS) based on abdominal ultrasound (secondary outcomes included computed tomography and magnetic resonance imaging). Among 26,577 patients with cirrhosis (median follow-up = 4.7 years), the mean PTUDS was 17.8 ± 21.5% (ultrasounds) and 23.3 ± 24.1% when any liver imaging modality was included. The strongest predictor of increased PTUDS was the number of visits to a specialist (gastroenterologist/hepatologist and/or infectious diseases) in the first year after cirrhosis diagnosis; the association between visits to a primary care physician and increasing surveillance was very small. Increasing distance to the closest Veterans Administration center was associated with decreased PTUDS. There was an inverse association between ultrasound lead time (difference between the date an ultrasound was ordered and requested exam date) and the odds of it being performed: odds ratio = 0.77, 95% confidence interval 0.72-0.82 when ordered > 180 days ahead of time; odds ratio = 0.90, 95% confidence interval 0.85-0.94 if lead time 91-180 days.

CONCLUSIONS

The responsibility for suboptimal surveillance rests with patients, providers, and the overall health care system; several measures can be implemented to potentially increase HCC surveillance, including increasing patient-specialist visits and minimizing appointment lead time. (Hepatology 2017;65:864-874).

The effect of surgical experience on the amount of radiation exposure from fluoroscopy during dynamic hip screw fixation

INTRODUCTION Dynamic hip screw (DHS) fixation for proximal femur fractures is one of the most common procedures in trauma that requires the use of fluoroscopy. Emphasis is often placed on producing the 'perfect picture', which may lead to excessive use of fluoroscopy, without added patient benefit. This study, the largest of its kind, aimed to determine the effect of surgical experience on the amount of radiation exposure from fluoroscopy during DHS fixation. METHODS All hospital admissions for extracapsular proximal femur fractures to our institution between 2007 and 2012 were analysed. Patient demographics, fracture configuration, grade of surgeon and the total radiation dose after fixation were recorded. Analysis of variance was performed to assess differences in radiation levels between different grades of surgeon. RESULTS A total of 1,203 patients with a mean age of 81.3 years (range: 21-105 years) were included in the study. The majority of the fractures were three-part (33.3%), followed by two-part (32.2%), four-part (25.7%) and basicervical (8.9%). Registrars (ST3-ST8) used a significantly higher radiation dose than consultants for all fracture types (p=0.009). When analysed separately by trainee group, the most junior registrars (ST3-ST4) and the most senior registrars (ST7-ST8) were found to use significantly higher radiation levels than consultants (p=0.037 and p<0.001 respectively). CONCLUSIONS The level of surgical experience does influence the amount of radiation exposure from fluoroscopy during DHS fixation. Surgical trainees should not ignore the potential harmful effects of radiation and should be equipped with the knowledge of how to keep the radiation exposure as low as possible.

Abstract P6-11-10: Preclinical efficacy of the novel PIM2 kinase inhibitor, JP11646 in triple negative breast cancer models

Background: Triple negative breast cancer (TNBC) patients have poorer prognosis and there remains a lack of novel targeted therapies for their treatment. PIM2 (Proviral Integrations of Moloney virus 2) belongs to a family of three kinases that have been implicated in the survival and progression of hematologic malignancies and solid tumors. PIM2 has been linked to epithelial to mesenchymal transition in TNBC, which can lead to metastasis and chemotherapeutic resistance. We hypothesized that PIM2 may present as a therapeutic target in TNBC.

Materials and Methods: The study involved both in vitro and in vivo studies involving a novel PIM2 inhibitor JP11646 (obtained from Jasco Pharmaceuticals). TNBC cell lines MDA-MB-231 and BT-549 were obtained for our in vitro studies. Cell viability was evaluated using MTT assay. Western Blot assay was used to evaluate relative protein expression. For in vivo studies, female SCID mice were inoculated in the mammary fat pads with 1 × 106 MDA-MB-231 cells. When tumor volumes reached 100 mm3, the mice were treated with JP11646 at the dosage 15mg/kg intraperitoneally for 2 consecutive days weekly for total of 4 weeks as determined from previous experiments. Control animals received vehicle only. The mice were euthanized once tumors reached ∼1,700 mm3.

Results: BT-549 cells treated in vitro with 3 different available PIM kinase inhibitors AZD 1208, LGB321 and JP12641 showed only modest reduction in cell viability. However, treatment of both MDA-MB-231 and BT-549 with JP 11646 demonstrated significant reduction in cell viability with IC50 ranging from 40 to 71.6 nM. Treatment with JP11646 demonstrated a novel mechanism of action resulting in downregulation of PIM2 in both cell lines. Treatment with JP11646, but not other PIM kinase inhibitors, resulted in activation of apoptosis as measured by cleaved PARP (cPARP) levels. Anti-PIM2 siRNA treatment but not treatment with non-specific PIM kinase inhibitor AZD1208 resulted in cPARP induction. Inhibition of proteolysis by bortezomib resulted in preservation of PIM2 and inhibition of apoptosis as demonstrated by decreased cPARP levels after treatment with JP11646. PIM2 over-expressing clone of MDA-MB-231 cells showed enhanced proliferation and migration properties both in vitro and in vivo.Treatment of mice with orthotopically implanted MDA-MB-231 tumors with JP 11646 resulted in significant reduction in the tumor growth (p=0.0019) and increased overall survival (p=0.018) as compared to control mice.

Conclusions: PIM2 upregulation in TNBC cell line resulted in more aggressive phenotype. JP11646, through novel mechanism of action resulting in degradation of PIM2, showed robust activity in TNBC cell lines both in vitro and in vivo. Further correlative studies in tumors harvested from in vivo experiments are ongoing. These results encourage further exploration of use of JP11646 as a targeted agent in treatment of TNBC.

Citation Format: Mehta R, Kothai Guruswamy Sangameswaran D, Bezbatchenko K, Moore J, Gil M, Khoury T, Baldino C, Caserta J, Fetterly, Jr. G, Lee K, Adjei A, Opyrchal M. Preclinical efficacy of the novel PIM2 kinase inhibitor, JP11646 in triple negative breast cancer models [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-11-10.

Abstract P6-12-13: Single domain antibody (SBT-100) inhibits growth of human HER2+ and triple negative breast cancers (TNBC) in xenografts by binding STAT3 and P-STAT3

SBT-100 is a single domain antibody (sdAb), developed by Singh Biotechnology, that binds unphosphorylated signal transducer and activator of transcription 3 (STAT3) and phosphorylated STAT3 (P-STAT3). SBT-100 is approximately 13 kD or less than 1/10th the size of a human IgG molecule, and is able to cross the cell membrane to bind intracellular STAT3 and P-STAT3. This in turn inhibits its effects on genes that promote malignant behavior of cancer cells. SBT-100 has a short serum half-life but a long biological half-life. Since certain types of human breast cancers express P-STAT3, we wanted to determine if SBT-100 could inhibit the growth of human breast cancers in vitro and in vivo by studying its effects on MCF-7 (ER+/PR+), BT474 (HER2+), and MDA-MB-231 (TNBC) cells.

BACKGROUND: Many different types of human cancers (solid tumors, leukemias, and lymphomas) are dependent on constitutive expression of (P-STAT3) for their malignant phenotype. Growth factors, tyrosine kinase receptors, cytokines (IL-6, IL-11, IL-12, IL-23), BCR-ABL, and Src are some ways that STAT3 can be activated. In turn P-STAT3 turns on genes such as Cyclin D1 & D3, MMPs, Bcl-xL, Mcl-1, survivin, VEGF, and HIF-1 alpha. Constitutive expression of P-STAT3 has been shown to promote cancer cell proliferation, survival, angiogenesis, immune suppression, and metastasis. Additionally there is increasing evidence suggesting that unphosphorylated STAT3 contributes to malignant phenotype of cancers. STAT3 is also important for the survival of cancer stem cells as well as for some human breast cancers.

METHODS: Immunoprecipitation and Western blot analyses were carried out to test whether SBT-100 binds cytoplasmic STAT3 and P-STAT3 in various malignant cell lines (e.g., MDA-MB-231, PANC-1, DU145, and HeLa). MTT assays were done to determine if SBT-100 could suppress the growth of different types of human breast cancers in vitro. Xenograft cancer models using ER+/PR+ (MCF-7), HER2+ (BT474), and TNBC (MDA-MB-231) cancer cells were used to evaluate treatment with SBT-100 1mg/kg/BID (IV and/or IP route).

RESULTS: Immunoprecipitation and Western blot studies demonstrated that SBT-100 binds to both STAT3 and P-STAT3 in human cancers cells (MDA-MB-231, PANC-1, DU145, and HeLa). In a three day MTT assay, at least 90% growth suppression was achieved for all three subtypes of human breast cancer, which is highly significant. In the xenograft cancer models, SBT-100 (1mg/kg/BID) treatment for 28 days, yield growth suppression as follows: MDA-MB-231 44.8% (p&lt;0.05) versus its control group and BT474 52% (p&lt;0.07). While the MCF-7 xenograft cancer model showed no suppression.

CONCLUSION: Singh Biotechnology's novel sdAb, SBT-100 suppresses growth of TNBC and HER2+ human breast cancers in vivo and suppresses growth of ER+/PR+, HER2+, and TNBC cells in vitro. The most significant anti-cancer effects of SBT-100 is observed against human TNBC.

Citation Format: Singh S, Murillo G, Chen D, Singh A, Singh S, Singh A, Mehta R, Parihar A. Single domain antibody (SBT-100) inhibits growth of human HER2+ and triple negative breast cancers (TNBC) in xenografts by binding STAT3 and P-STAT3 [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-12-13.

Transfer-free multi-layer graphene as a diffusion barrier

Graphene is a promising ultra-thin barrier against undesired mass transport, however, the high deposition temperatures or the defect inducing post-deposition transfer processes limit its widespread applicability. Herein we report on the successful blocking of copper (Cu) ion diffusion by large area multi-layer graphene (MLG) membranes deposited directly on silicon oxide (SiO₂) via low temperature plasma-enhanced chemical vapor deposition. The barrier strength of MLG is compared to evaporated tantalum (Ta) by applying positive bias-temperature stress (BTS) to Cu/barrier/SiO₂/Si test structures. After constant BTS of 4 × 10⁶ V cm^-1 at 400 K for 50 min, the MLG barrier device exhibits a negligible flat band voltage shift in capacitance-voltage measurements and no discernible current peak in triangular voltage scans, whereas the Ta barrier allows significant Cu ion transport. Highly limited Cu ion diffusion through MLG suggests that lower energy diffusion paths, like grain boundaries and defects of individual graphene layers, do not align in the direction of an applied stress field. In general, the presented low-temperature direct growth MLG membranes can block undesirable diffusion in many applications, and are especially suitable as Cu diffusion barriers in integrated circuit chips, photovoltaic cells and flexible electronic devices.

Premenopausal abnormal uterine bleeding and risk of endometrial cancer

BACKGROUND

Endometrial biopsies are undertaken in premenopausal women with abnormal uterine bleeding but the risk of endometrial cancer or atypical hyperplasia is unclear.

OBJECTIVES

To conduct a systematic literature review to establish the risk of endometrial cancer and atypical hyperplasia in premenopausal women with abnormal uterine bleeding.

SEARCH STRATEGY

Search of PubMed, Embase and the Cochrane Library from database inception to August 2015.

SELECTION CRITERIA

Studies reporting rates of endometrial cancer and/or atypical hyperplasia in women with premenopausal abnormal uterine bleeding.

DATA COLLECTION AND ANALYSIS

Data were independently extracted by two reviewers and cross-checked. For each outcome, the risk and a 95% CI were estimated using logistic regression with robust standard errors to account for clustering by study.

MAIN RESULTS

Sixty-five articles contributed to the analysis. Risk of endometrial cancer was 0.33% (95% CI 0.23-0.48%, n = 29 059; 97 cases) and risk of endometrial cancer or atypical hyperplasia was 1.31% (95% CI 0.96-1.80, n = 15 772; 207 cases). Risk of endometrial cancer was lower in women with heavy menstrual bleeding (HMB) (0.11%, 95% CI 0.04-0.32%, n = 8352; 9 cases) compared with inter-menstrual bleeding (IMB) (0.52%, 95% CI 0.23-1.16%, n = 3109; 14 cases). Of five studies reporting the rate of atypical hyperplasia in women with HMB, none identified any cases.

CONCLUSIONS

The risk of endometrial cancer or atypical hyperplasia in premenopausal women with abnormal uterine bleeding is low. Premenopausal women with abnormal uterine bleeding should first undergo conventional medical management. Where this fails, the presence of IMB and older age may be indicators for further investigation. Further research into the risks associated with age and the cumulative risk of co-morbidities is needed.

TWEETABLE ABSTRACT

Contrary to practice, premenopausal women with heavy periods or inter-menstrual bleeding rarely require biopsy.

Up-titration of sorafenib for hepatocellular carcinoma: Impact on duration of exposure and cost

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Background: Few data exist how sorafenib starting dose impacts duration of exposure and cost of sorafenib therapy for patients with HCC. Methods: HCC patients exposed to sorafenib, initial doses, number of sorafenib fills, and medication exposure days were identified from the VA CDW using ICD9 codes and pharmacy records. ICD9 codes, CPT codes, AUDIT-C surveys and laboratory tests were utilized to characterize underlying liver disease, calculate Child-Turcotte-Pugh (CTP) and MELD scores. Two abstractors achieved 100% chart verification of tumor number, size, MVI/EHS on imaging proximate to sorafenib to quantify Barcelona Clinic Liver Cancer (BCLC) stage and to determine the provider specialty initiating sorafenib. Results: 2292 patients with BCLC B-C HCC, CTP A cirrhosis with ECOG PS ≤ 2 prescribed sorafenib for HCC between 2007 and 2015 were included in this interim analysis. Median age was 62; 98.8% were male, 61.8% white/26.0% black; Pre-sorafenib BCLC B-43%/C-57%. Prescription at full-dose became less common over 2007-2015, dropping from 80% to 48%. First-dose up-titration was more commonly done by hepatologists (21% vs. 4.5%, p < 0.0001), but oncologists were more likely to up-titrate at the second prescription (8.9% vs. 3.8%, p < 0.001). Overall, 38% of first sorafenib prescriptions were initiated at doses below 800mg/day; 43% were up-titrated whereas 57% never up-titrated. Patients starting at < 800 mg/d received fewer total pills (median 284 vs. 360, p = 0.008) but a greater number of prescription fills (median 4 vs. 3, p < 0.0001) and longer exposure duration (median 120 vs 90 days, p = 0.0012) at lower total cost (median $8,143 vs $9,685, p < 0.0001). Median overall survival for those starting < 800mg/d was not significantly different from full dose initiators (median 284 vs. 292 days, p = 0.33). Conclusions: Initiation of sorafenib < 800mg/d was associated with lower pill utilization, but longer exposure duration and equivalent survival at lower cost. Starting at a lower dose with uptitration may select patients with a higher likelihood of sustained benefit and improve cost-effective utilization of resources. This approach should be tested prospectively.

Sorafenib for hepatocellular carcinoma managed by non-oncologists: Impact on drug exposure and survival

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Background: Few data exist on practitioner type, initial dosing regimens, and survival for patients with HCC treated with sorafenib in a real-world setting. Methods: HCC patients exposed to sorafenib were identified from the VA CDW using ICD9 codes and pharmacy records. ICD9 codes, CPT codes, AUDIT-C surveys and laboratory tests were utilized to characterize underlying liver disease, calculate Child-Turcotte-Pugh (CTP) and MELD scores. Two abstractors achieved 100% chart verification of tumor number, size, macrovascular invasion and extrahepatic spread on imaging immediately proximate to sorafenib initiation to quantify Barcelona Clinic Liver Cancer (BCLC) stage and to determine the provider specialty initiating sorafenib. Results: 4838 patients prescribed sorafenib for HCC between 2008 and 2015 were included in this interim analysis. Median age was 62; 98.8% were male, 61.8% white/26.0% black; 44% EtOH/54% HCV/5% HBV/29% other; CTP A 58%/B 37%/C 4%; median MELD 11; 96% ECOG < 2; and pre-sorafenib BCLC 0-0%/A-5%/B-37%/C-49%/D-8%. Sorafenib was prescribed by oncologists (92%), GI/hepatologists (7.6%) and other practitioners (0.4%). Patients treated by GI/hepatologists rather than oncologists had similar BCLC distributions, similar treatment durations (median 90 vs. 90 days), received more pills (median 360 vs. 240, p = 0.0016), but had identical survival (median 234 vs. 239 days, p = NS). Hepatologists were more likely than oncologists to uptitrate during the first month (25% vs. 14%, p < 0.0001) whereas oncologists were more likely to uptitrate later (8.9% vs. 3.8%, p < 0.001). Oncologists were more likely to stop sorafenib due to progression (29 vs. 18%), while hepatologists were more likely to continue sorafenib until death (28 v. 18%) with no difference in discontinuation for AEs or functional decline. In multivariable models including CTP, BCLC, and ECOG PS, prescriber specialty had no impact on OS. Conclusions: In the VA, 8% of sorafenib is prescribed by GI/hepatologists. Despite modest differences in prescribing practices, hepatologists and oncologists achieve similar sorafenib exposure and overall median survival rates of 7.8 months in real-world practices.

Investigation into the Effect of Ethylcellulose Viscosity Variation on the Drug Release of Metoprolol Tartrate and Acetaminophen Extended Release Multiparticulates-Part I

Ethylcellulose is one of the most commonly used polymers to develop reservoir type extended release multiparticulate dosage forms. For multiparticulate extended release dosage forms, the drug release is typically governed by the properties of the barrier membrane coating. The ICH Pharmaceutical Development Guideline (ICH Q8) requires an understanding of the influence of critical material attributes and critical process parameters on the drug release of a pharmaceutical product. Using this understanding, it is possible to develop robust formulations with consistent drug release characteristics. Critical material attributes for ethylcellulose were evaluated, and polymer molecular weight variation (viscosity) was considered to be the most critical attribute that can impact drug release. To investigate the effect of viscosity variation within the manufacturer's specifications of ethylcellulose, extended release multiparticulate formulations of two model drugs, metoprolol tartrate and acetaminophen, were developed using ETHOCEL™ as the rate controlling polymer. Quality by Design (QbD) samples of ETHOCEL Std. 10, 20, and 100 Premium grades representing the low, medium, and high molecular weight (viscosity) material were organically coated onto drug layered multiparticulates to a 15% weight gain (WG). The drug release was found to be similar (f ₂ > 50) for both metoprolol tartrate and acetaminophen multiparticulates at different coating weight gains of ethylcellulose, highlighting consistent and robust drug release performance. The use of ETHOCEL QbD samples also serves as a means to develop multiparticulate dosage formulations according to regulatory guidelines.