Martin Goros

Limited value of plasma cytokeratin-18 as a biomarker for NASH and fibrosis in patients with non-alcoholic fatty liver disease

BACKGROUND & AIMS Liver biopsy is the only reliable way of diagnosing and staging NASH but its invasive nature limits its use. Plasma caspase-generated cytokeratin-18 fragments (CK-18) have been proposed as a non-invasive alternative. We studied its clinical value in a large multiethnic NAFLD population and examined its relationship to clinical/metabolic/histological parameters. METHODS 424 middle-aged subjects in whom we measured adipose tissue, liver and muscle insulin resistance (IR), liver fat by MRS (n=275) and histology (n=318). RESULTS Median CK-18 were elevated in patients with vs. without NAFLD by MRS (209 [IQR: 137-329] vs. 122 [IQR: 98-155]U/L) or with vs. without NASH (232 [IQR: 151-387] vs. 170 [IQR: 135-234]U/L, both p<0.001). Plasma CK-18 raised significantly with any increase in steatosis, inflammation and fibrosis, but there was a significant overlap across disease severity. The CK-18 AUROC to predict NAFLD, NASH or fibrosis were 0.77 (95% CI=0.71-0.84), 0.65 (95% CI=0.59-0.71) and 0.68 (95% CI=0.61-0.75), respectively. The overall sensitivity/specificity for NAFLD, NASH and fibrosis were 63% (57-70%)/83% (69-92%), 58% (51-65%)/68% (59-76%) and 54% (44-63%)/85% (75-92%), respectively. CK-18 correlated most strongly with ALT (r=0.57, p<0.0001) and adipose tissue IR (insulin-suppression of FFA: r=-0.43; p<0.001), less with steatosis, lobular inflammation and fibrosis (r=0.28-0.34, all p<0.001), but not with ballooning, BMI, metabolic syndrome or T2DM. CONCLUSIONS Plasma CK-18 has a high specificity for NAFLD and fibrosis, but its limited sensitivity makes it inadequate as a screening test for staging NASH. Whether combined as a diagnostic panel with other biomarkers or clinical/laboratory tests may prove useful requires further study.

Lineage of origin in rhabdomyosarcoma informs pharmacological response

Lineage or cell of origin of cancers is often unknown and thus is not a consideration in therapeutic approaches. Alveolar rhabdomyosarcoma (aRMS) is an aggressive childhood cancer for which the cell of origin remains debated. We used conditional genetic mouse models of aRMS to activate the pathognomonic Pax3:Foxo1 fusion oncogene and inactivate p53 in several stages of prenatal and postnatal muscle development. We reveal that lineage of origin significantly influences tumor histomorphology and sensitivity to targeted therapeutics. Furthermore, we uncovered differential transcriptional regulation of the Pax3:Foxo1 locus by tumor lineage of origin, which led us to identify the histone deacetylase inhibitor entinostat as a pharmacological agent for the potential conversion of Pax3:Foxo1-positive aRMS to a state akin to fusion-negative RMS through direct transcriptional suppression of Pax3:Foxo1.

Dynamic and Nuclear Expression of PDGFRα and IGF-1R in Alveolar Rhabdomyosarcoma

Since the advent of tyrosine kinase inhibitors as targeted therapies in cancer, several receptor tyrosine kinases (RTK) have been identified as operationally important for disease progression. Rhabdomyosarcoma (RMS) is a malignancy in need of new treatment options; therefore, better understanding of the heterogeneity of RTKs would advance this goal. Here, alveolar RMS (aRMS) tumor cells derived from a transgenic mouse model expressing two such RTKs, platelet-derived growth factor (PDGFR)α and insulin-like growth factor (IGF)-1R, were investigated by fluorescence-activated cell sorting (FACS). Sorted subpopulations that were positive or negative for PDGFRα and IGF-1R dynamically altered their cell surface RTK expression profiles as early as the first cell division. Interestingly, a difference in total PDGFRα expression and nuclear IGF-1R expression was conserved in populations. Nuclear IGF-1R expression was greater than cytoplasmic IGF-1R in cells with initially high cell surface IGF-1R, and cells with high nuclear IGF-1R established tumors more efficiently in vivo. RNA interference–mediated silencing of IGF-1R in the subpopulation of cells initially harboring higher cell surface and total IGF-1R resulted in significantly reduced anchorage-independent colony formation as compared with cells with initially lower cell surface and total IGF-1R expression. Finally, in accordance with the findings observed in murine aRMS, human aRMS also had robust expression of nuclear IGF-1R. Implications: RTK expression status and subcellular localization dynamics are important considerations for personalized medicine. Mol Cancer Res; 11(11); 1303–13. ©2013 AACR.

Vorinostat and hydroxychloroquine improve immunity and inhibit autophagy in metastatic colorectal cancer

Hydroxychloroquine (HCQ) enhances the anti-cancer activity of the histone deacetylase inhibitor, vorinostat (VOR), in pre-clinical models and early phase clinical studies of metastatic colorectal cancer (mCRC). Mechanisms could include autophagy inhibition, accumulation of ubiquitinated proteins, and subsequent tumor cell apoptosis. There is growing evidence that autophagy inhibition could lead to improved anti-cancer immunity. To date, effects of autophagy on immunity have not been reported in cancer patients. To address this, we expanded an ongoing clinical study to include patients with advanced, refractory mCRC to evaluate further the clinical efficacy and immune effects of VOR plus HCQ. Refractory mCRC patients received VOR 400 milligrams orally with HCQ 600 milligrams orally daily, in a 3-week cycle. The primary endpoint was median progression-free survival (mPFS). Secondary endpoints include median overall survival (mOS), adverse events (AE), pharmacodynamic of inhibition of autophagy in primary tumors, immune cell analyses, and cytokine levels. Twenty patients were enrolled (19 evaluable for survival) with a mPFS of 2.8 months and mOS of 6.7 months. Treatment-related grade 3–4 AEs occurred in 8 patients (40%), with fatigue, nausea/vomiting, and anemia being the most common. Treatment significantly reduced CD4+CD25hiFoxp3+ regulatory and PD-1+ (exhausted) CD4+ and CD8+ T cells and decreased CD45RO-CD62L+ (naive) T cells, consistent with improved anti-tumor immunity. On-study tumor biopsies showed increases in lysosomal protease cathepsin D and p62 accumulation, consistent with autophagy inhibition. Taken together, VOR plus HCQ is active, safe and well tolerated in refractory CRC patients, resulting in potentially improved anti-tumor immunity and inhibition of autophagy.

An evaluation of elderly patients (≥ 70 years old) enrolled in Phase I clinical trials at University of Texas Health Science Center at San Antonio-Cancer Therapy Research Center from 2009 to 2011

OBJECTIVE Elderly patients with cancer are under-represented in clinical trials, and there is especially scant data on their participation in early-phase trials. In an effort to provide more data, we reviewed our Phase I experience. METHODS We conducted a retrospective analysis of 461 patients enrolled in Phase I clinical trials at the Cancer Therapy Research Center (CTRC) from 2009 to 2011 to determine the rate of completion of at least 12 weeks of treatment, incidence of adverse events, prevalence of co-morbidities, functional status, and survival. Elderly (E) was defined as ≥70 years; non-elderly (NE) was defined as ≤69 years. RESULTS The elderly represented 15% (69/461) of enrolled patients. The most common malignancies were colon (20%), hematologic (18%), lung (15%), and breast (8%). The median age of E was 72 years (range 70-85, SD 3.15), and 49% of the E was female. Co-morbidities (E vs. NE) include diabetes (28% vs. 23%), hypertension (65% vs. 44%), and chronic kidney disease (91% vs. 48%). Thirty-two percent of E vs. 37% of NE completed at least 12 weeks of treatment. Reasons for not completing in E vs. NE respectively were progression of disease (43% vs. 61%), toxicity (28% vs. 9%), and self-withdrawal (11% vs. 7%). Reasons for not completing the protocol was significantly associated with being elderly (p = 0.005). There were non-significant differences in toxicity in E vs. NE CONCLUSION Elderly patients have a higher likelihood of not completing trials for reasons including toxicity. This highlights the need for better Phase I trial-designs incorporating ideal geriatric assessment tools.

p53‐Based strategy to reduce hematological toxicity of chemotherapy: A proof of principle study

p53 activation is a primary mechanism underlying pathological responses to DNA damaging agents such as chemotherapy and radiotherapy. Our recent animal studies showed that low dose arsenic (LDA)‐induced transient p53 inhibition selectively protected normal tissues from chemotherapy‐induced toxicity.

Older Stroke Patients with High Stroke Scores Have Delayed Door-To-Needle Times

INTRODUCTION The timely administration of intravenous (IV) tissue plasminogen activator (t-PA) to acute ischemic stroke patients from the period of symptom presentation to treatment, door-to-needle (DTN) time, is an important focus for quality improvement and best clinical practice. METHODS A retrospective review of our Get With The Guidelines database was performed for a 5-hospital telestroke network for the period between January 2010 and January 2015. All acute ischemic stroke patients who were triaged in the emergency departments connected to the telestroke network and received IV t-PA were included. Optimal DTN time was defined as less than 60 minutes. Logistic regression was performed with clinical variables associated with DTN time. Age and National Institutes of Health Stroke Scale (NIHSS) score were categorized based on clinically significant cutoffs. RESULTS Six-hundred and fifty-two patients (51% women, 46% White, 45% Hispanic, and 8% Black) were included in this study. The mean age was 70 years (range 29-98). Of the variables analyzed, only arrival mode, initial NIHSS score, and the interaction between age and initial NIHSS score were significant. DTN time more than or equal to 60 minutes was most common in patients aged more than 80 years with NIHSS score higher than 10. CONCLUSIONS The cause of DTN time delay for older patients with higher NIHSS score is unclear but was not related to presenting blood pressure or arrival mode. Further study of this subgroup is important to reduce overall DTN times.

Metabolic Biosynthesis Pathways Identified from Fecal Microbiome Associated with Prostate Cancer

BACKGROUND The fecal microbiome is associated with prostate cancer risk factors (obesity, inflammation) and can metabolize and produce various products that may influence cancer but have yet to be defined in prostate cancer. OBJECTIVE To investigate gut bacterial diversity, identify specific metabolic pathways associated with disease, and develop a microbiome risk profile for prostate cancer. DESIGN, SETTING, AND PARTICIPANTS After prospective collection of 133 rectal swab samples 2 wk before the transrectal prostate biopsy, we perform 16S rRNA amplicon sequencing on 105 samples (64 with cancer, 41 without cancer). Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was applied to infer functional categories associated with taxonomic composition. The p values were adjusted using the false discovery rate. The α- and β-diversity analyses were performed using QIIME. The Mann-Whitney U test was employed to evaluate the statistical significance of β-diversity distances within and between groups of interest, and least absolute shrinkage and selection operator (LASSO) regression analysis was used to determine pathway significance. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The detection of prostate cancer on transrectal prostate needle biopsy and 16s microbiome profile. RESULTS AND LIMITATIONS We identified significant associations between total community composition and cancer/non-cancer status (Bray-Curtis distance metric, p<0.01). We identified significant differences in enrichments of Bacteroides and Streptococcus species in cancer (all p<0.04). Folate (LDA 3.8) and arginine (LDA 4.1) were the most significantly altered pathways. We formed a novel microbiome-derived risk factor for prostate cancer based on 10 aberrant metabolic pathways (area under curve=0.64, p=0.02). CONCLUSIONS Microbiome analyses on men undergoing prostate biopsy noted mostly similar bacterial species diversity among men diagnosed with and without prostate cancer. The microbiome may have subtle influences on prostate cancer but are likely patient-specific and would require paired analysis and precise manipulation, such as improvement of natural bacterial folate production. PATIENT SUMMARY Microbiome evaluation may provide patients with personalized data regarding the presence or absence of particular bacteria that have metabolic functions and implications regarding prostate cancer risk. The study provides a basis to investigate the manipulation of aberrant microbiomes to reduce prostate cancer risk.

The Effect of Trabeculae Carneae on Left Ventricular Diastolic Compliance: Improvement in Compliance With Trabecular Cutting

The role of trabeculae carneae in modulating left ventricular (LV) diastolic compliance remains unclear. The objective of this study was to determine the contribution of trabeculae carneae to the LV diastolic compliance. LV pressure-volume compliance curves were measured in six human heart explants from patients with LV hypertrophy at baseline and following trabecular cutting. The effect of trabecular cutting was also analyzed with finite-element model (FEM) simulations. Our results demonstrated that LV compliance improved after trabecular cutting (p < 0.001). Finite-element simulations further demonstrated that stiffer trabeculae reduce LV compliance further, and that the presence of trabeculae reduced the wall stress in the apex. In conclusion, we demonstrate that integrity of the LV and trabeculae is important to maintain LV stiffness and loss in trabeculae leads to more LV compliance.

Improving Initiation and Tracking of Research Projects at an Academic Health Center: A Case Study.

Research service cores at academic health centers are important in driving translational advancements. Specifically, biostatistics and research design units provide services and training in data analytics, biostatistics, and study design. However, the increasing demand and complexity of assigning appropriate personnel to time-sensitive projects strains existing resources, potentially decreasing productivity and increasing costs. Improving processes for project initiation, assigning appropriate personnel, and tracking time-sensitive projects can eliminate bottlenecks and utilize resources more efficiently. In this case study, we describe our application of lean six sigma principles to our biostatistics unit to establish a systematic continual process improvement cycle for intake, allocation, and tracking of research design and data analysis projects. The define, measure, analyze, improve, and control methodology was used to guide the process improvement. Our goal was to assess and improve the efficiency and effectiveness of operations by objectively measuring outcomes, automating processes, and reducing bottlenecks. As a result, we developed a web-based dashboard application to capture, track, categorize, streamline, and automate project flow. Our workflow system resulted in improved transparency, efficiency, and workload allocation. Using the dashboard application, we reduced the average study intake time from 18 to 6 days, a 66.7% reduction over 12 months (January to December 2015).