Herbert Pang

The University of Hong Kong, Hong Kong, Hong Kong

Are you Herbert Pang?

Claim your profile

Publications (49)240.87 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Inhibition of tumor angiogenesis is an effective mechanism to limit tumor growth; dual inhibition may result in additional benefit. Bevacizumab is a monoclonal antibody directed against vascular endothelial growth factor (VEGF), and intetumumab is a fully humanized monoclonal antibody that blocks αv integrins when complexed with β integrins. We evaluated the safety, tolerability, and efficacy of the combination of bevacizumab plus intetumumab in patients with refractory solid tumors. We also explored the effects of these agents on plasma-based biomarkers and wound angiogenesis. Patients with refractory solid tumors, Karnofsky performance status ≥70 %, and adequate organ function were eligible. Plasma samples and wound biopsies were obtained at baseline and on-treatment. Twelve patients were enrolled and received study drug. No tumor responses were noted. Observed toxicities included three cases of transient uveitis likely related to intetumumab and one case of reversible posterior leukoencephalopathy syndrome likely related to bevacizumab. Biomarker analysis revealed changes in soluble endoglin, soluble E-cadherin, and soluble E-selectin as well as PlGF and VEGF-D while on treatment. There was no observed impact of bevacizumab plus intetumumab on the phosphorylated or total levels of paxillin in wound tissue; however, an increase in the ratio of phospho/total paxillin levels was noted. Bevacizumab and intetumumab can be administered safely in combination. Bevacizumab plus intetumumab treatment resulted in changes in the plasma levels of several extracellular matrix interacting proteins and angiogenic factors.
    Cancer Chemotherapy and Pharmacology 12/2014; · 2.80 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Thyroid hormone (TH) is important for tissue repair because it regulates cellular differentiation. Intrahepatic TH activity is controlled by both serum TH levels and hepatic deiodinases. TH substrate (thyroxine, T4) is converted into active hormone (triidothyronine, T3) by deiodinase 1 (D1), but into inactive hormone (reverse T3, rT3) by deiodinase 3 (D3). Although the relative expressions of D1 and D3 are known to change during liver injury, the cell types and signaling mechanisms involved are unclear. We evaluated the hypothesis that changes in hepatic deiodinases result from repairrelated activation of the Hedgehog pathway in stromal cells. We localized deiodinase expression, assessed changes during injury, and determined how targeted manipulation of Hedgehog signaling in stromal cells impacted hepatic deiodinase expression, TH content, and TH action in rodents. Humans with chronic liver disease were also studied. In healthy liver, hepatocytes strongly expressed D1 and stromal cells weakly expressed D3. During injury, hepatocyte expression of D1 decreased, while stromal expression of D3 increased, particularly in myofibroblasts. Conditionally disrupting Hedgehog signaling in myofibroblasts normalized deiodinase expression. Repairrelated changes in deiodinases were accompanied by reduced hepatic TH content and TH-regulated gene expression. In patients, this was reflected by increased serum rT3. Moreover, decreases in fT3/rT3 and fT4/rT3 distinguished advanced from mild fibrosis, even in individuals with similar serum levels of TSH and fT4. Conclusion: Hedgehog-dependent changes in liver stromal cells drive repair-related changes in hepatic deiodinase expression that promote intrahepatic hypothyroidism, thereby limiting exposure to T3, an important factor for cellular differentiation.
    Endocrinology 08/2014; · 4.72 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose To define maximum tolerated dose (MTD), toxicities, and pharmacodynamics of capecitabine, oxaliplatin, bevacizumab, and everolimus in advanced solid tumor patients. Design This was a standard "3 + 3" dose-escalation trial. All subjects received bevacizumab 7.5 mg/kg on day 1 of each cycle. Doses for capecitabine, oxaliplatin and everolimus were modified per dose limiting toxicity (DLT). Baseline and on-treatment plasma biomarkers were analyzed. Archived tumor mRNA levels were evaluated for NRP1, NRP2 and VEGF-A isoforms. Results Twenty-nine patients were evaluable for toxicity and 30 for efficacy. Two DLTs were observed in cohort 1 and one DLT each was observed in cohort -1 and -1b. Grade ≥3 toxicities included neutropenia, hypertension, perforation/fistula/hemorrhage, hypertriglyceridemia, diarrhea, and thromboembolism. Twelve subjects experienced partial response (PR); 12 had stable disease as best response. Three of seven chemorefractory metastatic colorectal cancer (mCRC) subjects experienced PR; 8 of 15 chemonaive mCRC subjects experienced PR. Plasma TβRIII and IL-6 increased on treatment but without correlation to outcome. Increased VEGF165 levels significantly correlated with longer progression free survival. Conclusions Everolimus with full dose capecitabine, oxaliplatin, and bevacizumab had unacceptable toxicity. MTD was: everolimus 5 mg daily; capecitabine 680 mg/m(2) BID days 1-14; oxaliplatin 100 mg/m(2) and bevacizumab 7.5 mg/kg, day 1. Activity was noted in mCRC.
    Investigational New Drugs 04/2014; · 3.50 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: TRC105 is an endoglin-targeting drug that possesses anti-angiogenic and antitumor potential. Analysis of the initial phase I trial of TRC105 demonstrated good tolerability and efficacy in cancer patients. In this report, we analyzed multiple circulating biomarkers at baseline, cycle 2 day 1 (C2D1), and end of study (EOS) for each patient. The baseline level and the fold change from baseline to both C2D1 and EOS for each marker were statistically analyzed. At C2D1, seven markers were significantly downregulated (angiopoietin-2 [Ang-2], insulin-like growth factor-binding protein-3 [IGFBP-3], plasminogen activator inhibitor-1 [PAI-1] total, platelet-derived growth factor [PDGF]-AA, PDGF-BB, thrombospondin-1 [TSP-1], and vascular endothelial growth factor [VEGF]-D). Meanwhile, seven markers were upregulated by C2D1 (E-Cadherin, soluble Endoglin [sEnd], E-Selectin, interleukin-6 [IL-6], osteopontin [OPN], TSP-2, and von Willebrand factor [vWF]). At EOS, seven markers were upregulated including Ang-2, C-reactive protein (CRP), intercellular adhesion molecule-1 (ICAM-1), IGFBP-1, IL-6, TSP-2, and vascular cell adhesion molecule-1 (VCAM-1). A statistical trend was also seen for increases of VEGF-A and placenta growth factor (PlGF) at EOS. Throughout treatment, sEnd levels significantly increased, an observation that was recapitulated in cultured endothelial cells. This is the first report of plasma-based biomarkers in patients receiving TRC105. TRC105 treatment by C2D1 was associated with decreases in several angiogenic factors, including Ang-2, PDGF isoforms, and VEGF isoforms, offering insight into the mechanisms underlying TRC105's anti-angiogenic, antitumor function. Increases in sEnd were the most significant of all observed biomarker changes and may reflect direct drug effects. Additionally, biomarker changes in response to TRC105 are distinct from those seen in patients treated with VEGF-targeting drugs, suggesting the possible utility of combining these two classes of angiogenesis inhibitors in patients.
    Cancer Medicine 02/2014;
  • Article: Reply.
    Hepatology 02/2014; · 12.00 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Recent method development has included multi-dimensional genomic data algorithms because such methods have more accurately predicted clinical phenotypes related to disease. This study is the first to conduct an integrative genomic pathway-based analysis with a graph-based learning algorithm. The methodology of this analysis, graph-based semi-supervised learning, detects pathways that improve prediction of a dichotomous variable, which in this study is cancer stage. This analysis integrates genome-level gene expression, methylation, and single nucleotide polymorphism (SNP) data in serous cystadenocarcinoma (OV) and colon adenocarcinoma (COAD). The top 10 ranked predictive pathways in COAD and OV were biologically relevant to their respective cancer stages and significantly enhanced prediction accuracy and area under the ROC curve (AUC) when compared to single data-type analyses. This method is an effective way to simultaneously predict binary clinical phenotypes and discover their biological mechanisms.
    Cancer informatics 01/2014; 13(Suppl 4):1-9.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Standard therapy for limited stage small cell lung cancer (L-SCLC) is concurrent chemotherapy and radiotherapy followed by prophylactic cranial radiotherapy. Predictors of post chemoradiotherapy pulmonary toxicity in limited stage (LS) small cell lung cancer (SCLC) patients are not well defined. Current guidelines are derived from non-small cell lung cancer regimens, and do not account for the unique biology of this disease. Therefore, we analyzed patients on three consecutive CALGB LS-SCLC trials treated with concurrent chemotherapy and daily high dose radiotherapy (70 Gy) to determine patient and treatment related factors predicting for post-treatment pulmonary toxicity. Patients treated on CALGB protocols 39808, 30002, 30206 investigating two cycles of chemotherapy followed by concurrent chemotherapy and 70 Gy daily thoracic radiation therapy were pooled. Patient, tumor, and treatment related factors were evaluated to determine predictors of grade 3–5 pulmonary toxicities after concurrent chemoradiotherapy. 100 patients were included. No patient experienced grade 4–5 post-treatment pulmonary toxicity. Patients who experienced post-treatment pulmonary toxicity were more likely to be older (median age 69 vs 60, p = 0.09) and have smaller total lung volumes (2565 cc vs 3530 cc, p = 0.05).). Furthermore,exposure of larger volumes of lung to lower (median V5 = 70%, p = 0.09, median V10 = 63%, p = 0.07), inter-mediate (median V20 = 50, p = 0.04) and high (median V60 = 25%, p = 0.01) doses of radiation were all associated with post-treatment grade 3 pulmonary toxicity, as was a larger mean lung radiation dose(median 31 Gy) p = 0.019. Post-treatment pulmonary toxicity following the completion of 2 cycles of chemotherapy followed by concurrent chemotherapy and high dose daily radiation therapy was uncommon. Care should be taken to minimize mean lung radiation exposure, as well as volumes of low, intermediate and high doses of radiation.
    Lung cancer (Amsterdam, Netherlands) 12/2013; 82(3):436-40. · 3.14 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Purpose Dasatinib inhibits src family kinases and has anti-angiogenic properties. We conducted a phase I study of dasatinib, capecitabine, oxaliplatin, and bevacizumab (CapeOx/bevacizumab), with an expansion cohort in metastatic colorectal cancer (CRC). Methods Patients were enrolled in a dose escalation cohort to establish the maximum tolerated dose (MTD) and the recommended phase II dose (RP2D). Using a "3 + 3" design, twelve patients with advanced solid tumors received dasatinib (50 mg twice daily or 70 mg daily), capecitabine (850 mg/m(2) twice daily, days 1-14), oxaliplatin (130 mg/m(2) on day 1) and bevacizumab (7.5 mg/kg on day1), every 3 weeks. Ten patients with previously untreated metastatic CRC were then enrolled in an expansion cohort. Activated src (srcact) expression was measured by immunohistochemistry, using an antibody that selectively recognizes the active conformation of src (clone 28). Results Twenty-two patients were enrolled between June 2009 and May 2011. Two DLTs were observed in the 50 mg bid dasatinib cohort, and one DLT was observed in the 70 mg daily dasatinib cohort. The MTD and RP2D for dasatinib was 70 mg daily. The most common treatment-related adverse events were fatigue (20; 91 %) and diarrhea (18; 82 %). Biomarker analysis of srcact expression demonstrated that the overall response rate (ORR) was 75 % (6/8) for patients with high srcact expression (IHC ≥ 2), compared to 0 % (0/8) for patients with low srcact expression (IHC 0 or 1); (p = 0.007). Conclusions The RP2D of dasatinib is 70 mg daily in combination with CapeOx/bevacizumab. High levels of srcact expression may predict those patients most likely to benefit from dasatinib.
    Investigational New Drugs 11/2013; · 3.50 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: CALGB80303 was a phase III trial of 602 patients with locally advanced or metastatic pancreatic cancer comparing gemcitabine/bevacizumab vs. gemcitabine/placebo. The study found no benefit in any outcome from the addition of bevacizumab to gemcitabine. Blood samples were collected and multiple angiogenic factors were evaluated and then correlated with clinical outcome in general (prognostic markers) and with benefit specifically from bevacizumab treatment (predictive markers). Plasma samples were analyzed via a novel multiplex ELISA platform for 31 factors related to tumor growth, angiogenesis, and inflammation. Baseline values for these factors were correlated with overall survival using univariate Cox proportional hazard regression models and multivariable Cox regression models with leave-one-out cross validation. Predictive markers were identified using a treatment by marker interaction term in the Cox model. Baseline plasma was available from 328 patients. Univariate prognostic markers for OS were identified including: Ang2, CRP, ICAM-1, IGFBP-1, TSP-2 (all p<0.001). These prognostic factors were found to be highly significant, even after adjustment for known clinical factors. Additional modeling approaches yielded prognostic signatures from multivariable Cox regression. The gemcitabine/bevacizumab signature consisted of IGFBP-1, IL-6, PDGF-AA, PDGF-BB, TSP-2; while the gemcitabine/placebo signature consisted of CRP, IGFBP-1, PAI-1, PDGF-AA, P-selectin (both p<0.0001). Lastly, three potential predictive markers of bevacizumab efficacy were identified: VEGF-D (p<0.01), SDF1 (p<0.05), and Ang2 (p<0.05). This study identified strong prognostic markers for pancreatic cancer patients. Predictive marker analysis indicated that plasma levels of VEGF-D, Ang2, and SDF1 significantly predicted for benefit or lack of benefit from bevacizumab in this population.
    Clinical Cancer Research 10/2013; · 7.84 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Estrogens inhibit stellate cell activation and fibrogenesis. Thus, gender and reproductive states may influence the degree of fibrosis in patients with nonalcoholic steatohepatitis (NASH). To investigate the association between gender, menopause, and the severity of liver fibrosis in patients with NASH, we analyzed 541 adult patients enrolled from our Duke Liver Clinics (n=338) and the Duke Metabolic and Weight Loss Surgery Program (n=203) who had a histologic diagnosis of NASH. Multiple ordinal logistic regression models were used to assess the association between gender, menopause and severity of liver fibrosis. Overall, men, pre-menopausal and post-menopausal women composed 35.1%, 28.4%, and 36.5% of the population, respectively. The mean age was 48 years and 22% had advanced fibrosis. After adjusting for covariates (enrolling site, grades of portal inflammation, and hepatocyte ballooning) and potential confounders (race, body mass index, diabetes/prediabetes, hypertension), adjusted cumulative odd ratio (ACOR) and 95% confidence interval (CI) for greater fibrosis severity was 1.4 [0.9, 2.1] (p=0.17) for post-menopausal women and 1.6 [1.0, 2.5] (p=0.03) for men, having pre-menopausal women as a reference. There was borderline interaction between gender and age group divided by age 50, the average age at menopause in the US (p=0.08): ACOR and 95% CI of having greater fibrosis severity in men compared to women was 1.8 [1.1, 2.9] for patients with age <50 years (p=0.02) and 1.2 [0.7, 2.1] for patients with age ≥ 50 years (p=0.59). Conclusion: Men are at a higher risk of having more severe fibrosis compared to women before menopause, while post-menopausal women have a similar severity of liver fibrosis compared to men. These findings may be explained by the protective effects of estrogen against fibrogenesis. (Hepatology 2013;).
    Hepatology 10/2013; · 12.00 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Clinicians rely upon the severity of liver fibrosis to segregate patients with well-compensated nonalcoholic fatty liver disease (NAFLD) into sub-populations at high versus low-risk for eventual liver-related morbidity and mortality. We compared hepatic gene expression profiles in high- and low-risk NAFLD patients to identify processes that distinguish the two groups and hence, might be novel biomarkers or treatment targets. Microarray analysis was used to characterize gene expression in percutaneous liver biopsies from low-risk, "mild" NAFLD patients (fibrosis stage 0-1, n=40) and high risk, "severe" NAFLD patients (fibrosis stage 3-4, n=32). Findings were validated in a second, independent cohort and confirmed by real time PCR and immunohistochemistry. As a group, patients at risk for bad NAFLD outcomes had significantly worse liver injury and more advanced fibrosis (severe NAFLD) than clinically-indistinguishable NAFLD patients with a good prognosis (mild NAFLD). A 64 gene profile reproducibly differentiated severe NAFLD from mild NAFLD, and a 20 gene subset within this profile correlated with NAFLD severity, independent of other factors known to influence NAFLD progression. Multiple genes involved with tissue repair/regeneration and certain metabolism-related genes were induced in severe NAFLD. Ingenuity Pathway Analysis and immunohistochemistry confirmed deregulation of metabolic and regenerative pathways in severe NAFLD, and revealed overlap among the gene expression patterns of severe NAFLD, cardiovascular disease, and cancer. Conclusion: By demonstrating specific metabolic and repair pathways that are differentially activated in livers with severe NAFLD, gene profiling identified novel targets that can be exploited to improve diagnosis and treatment of patients who are at greatest risk for NAFLD-related morbidity and mortality. (Hepatology 2013;).
    Hepatology 08/2013; · 12.00 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Cirrhosis and liver cancer are potential outcomes of advanced nonalcoholic fatty liver disease (NAFLD). It is not clear what factors determine whether patients will develop advanced or mild NAFLD, limiting non-invasive diagnosis and treatment before clinical sequelae emerge. We investigated whether DNA methylation profiles can distinguish patients with mild disease from those with advanced NAFLD, and how these patterns are functionally related to hepatic gene expression. We collected frozen liver biopsies and clinical data from patients with biopsy-proven NAFLD (56 in the discovery cohort and 34 in the replication cohort). Samples were divided into groups based on histologic severity of fibrosis: F0-1 (mild) and F3-4 (advanced). DNA methylation profiles were determined and coupled with gene expression data from the same biopsies; differential methylation was validated in subsets of the discovery and replication cohorts. We then analyzed interactions between the methylome and transcriptome. Clinical features did not differ between patients known to have mild or advanced fibrosis based on biopsy analysis. There were 69,247 differentially methylated CpG sites (76% hypomethylated, 24% hypermethylated) in patients with advanced vs mild NAFLD (P<.05). Methylation at FGFR2, MAT1A, and CASP1 was validated by bisulfite pyrosequencing and the findings were reproduced in the replication cohort. Methylation correlated with gene transcript levels for 7% of differentially methylated CpG sites, indicating that differential methylation contributes to differences in expression. In samples with advanced NAFLD, many tissue repair genes were hypomethylated and overexpressed, whereas genes in certain metabolic pathways, including 1-carbon metabolism, were hypermethylated and under-expressed. Functionally relevant differences in methylation can distinguish patients with advanced vs mild NAFLD. Altered methylation of genes that regulate processes such as steatohepatitis, fibrosis, and carcinogenesis indicate the role of DNA methylation in progression of NAFLD.
    Gastroenterology 07/2013; · 12.82 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Targeting multiple regulators of tumor angiogenesis have the potential to improve treatment efficacy. Bevacizumab is a monoclonal antibody directed against vascular endothelial growth factor and ABT-510 is a synthetic analog of thrombospondin, an endogenous angiogenesis inhibitor. Dual inhibition may result in additional benefit. We evaluated the safety, tolerability, and efficacy of the combination of bevacizumab plus ABT-510 in patients with refractory solid tumors. We also explored the effects of these agents on plasma-based biomarkers and wound angiogenesis. Thirty-four evaluable subjects were enrolled and received study drug. Therapy was well tolerated; minimal treatment-related grade 3/4 toxicity was observed. One patient treated at dose level 1 had a partial response and five other patients treated at the recommended phase II dose had prolonged stable disease for more than 1 year. Biomarker evaluation revealed increased levels of D-dimer, von Willebrand factor, placental growth factor, and stromal-derived factor 1 in response to treatment with the combination of bevacizumab and ABT-510. Data suggest that continued evaluation of combination antiangiogenesis therapies may be clinically useful.
    Cancer Medicine 06/2013; 2(3):316-24.
  • Herbert Pang, Tiejun Tong, Michael Ng
    [Show abstract] [Hide abstract]
    ABSTRACT: Abstract High-throughput expression profiling allows simultaneous measure of tens of thousands of genes at once. These data have motivated the development of reliable biomarkers for disease subtypes identification and diagnosis. Many methods have been developed in the literature for analyzing these data, such as diagonal discriminant analysis, support vector machines, and k-nearest neighbor methods. The diagonal discriminant methods have been shown to perform well for high-dimensional data with small sample sizes. Despite its popularity, the independence assumption is unlikely to be true in practice. Recently, a gene module based linear discriminant analysis strategy has been proposed by utilizing the correlation among genes in discriminant analysis. However, the approach can be underpowered when the samples of the two classes are unbalanced. In this paper, we propose to correct the biases in the discriminant scores of block-diagonal discriminant analysis. In simulation studies, our proposed method outperforms other approaches in various settings. We also illustrate our proposed discriminant analysis method for analyzing microarray data studies.
    Statistical Applications in Genetics and Molecular Biology 05/2013; · 1.52 Impact Factor
  • Inyoung Kim, Herbert Pang, Hongyu Zhao
    [Show abstract] [Hide abstract]
    ABSTRACT: Most statistical methods for microarray data analysis consider one gene at a time, and they may miss subtle changes at the single gene level. This limitation may be overcome by considering a set of genes simultaneously where the gene sets are derived from prior biological knowledge. We call a pathway as a predefined set of genes that serve a particular cellular or physiological function. Limited work has been done in the regression settings to study the effects of clinical covariates and expression levels of genes in a pathway on a continuous clinical outcome. A semiparametric regression approach for identifying pathways related to a continuous outcome was proposed by Liu et al. (2007), who demonstrated the connection between a least squares kernel machine for nonparametric pathway effect and a restricted maximum likelihood (REML) for variance components. However, the asymptotic properties on a semiparametric regression for identifying pathway have never been studied. In this paper, we study the asymptotic properties of the parameter estimates on semiparametric regression and compare Liu et al.'s REML with our REML obtained from a profile likelihood. We prove that both approaches provide consistent estimators, have [Formula: see text] convergence rate under regularity conditions, and have either an asymptotically normal distribution or a mixture of normal distributions. However, the estimators based on our REML obtained from a profile likelihood have a theoretically smaller mean squared error than those of Liu et al.'s REML. Simulation study supports this theoretical result. A profile restricted likelihood ratio test is also provided for the non-standard testing problem. We apply our approach to a type II diabetes data set (Mootha et al., 2003).
    Journal of Statistical Planning and Inference 04/2013; 143(4):745-763. · 0.71 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A novel combination of capecitabine, oxaliplatin, and bevacizumab was evaluated in colorectal cancer patients enrolled in a phase II clinical trial. In this retrospective analysis, plasma samples from patients receiving capecitabine, oxaliplatin, and bevacizumab were analyzed to investigate biomarkers of clinical benefit. Forty-one protein biomarkers were tested in 38 patients at baseline and after two cycles of drug administration. Correlations among analytes were evaluated by Spearman analysis. Analyte levels at baseline and changes on-treatment were correlated with progression-free survival (PFS) and overall survival (OS) by univariate analysis. Multivariate analyses were determined using the Cox proportional hazard model. Time to event analyses were evaluated by Kaplan-Meier analysis and compared by log-rank test. Baseline levels of vWF and Ang-2 significantly correlated with PFS, while levels of VCAM-1, vWF, TSP-2, IL-8, MMP-2, and Ang-2 correlated with OS (P < 0.05). The fold change of IGF-1 levels from baseline to the end of cycle 2 was correlated with PFS, while fold changes of Ang-2, TSP-2, and TGF-β2 correlated with OS. A baseline signature of Ang-2, IGFBP-3, IL-6, and VCAM-1 identified a low-risk and high-risk group of patients (OS: 33.9 months vs. 18.1 months, respectively, P = 0.016). For treatment-related changes, a signature consisting of Ang-2, E-Cadherin, IL-6, MCP-1, OPN, and TGF-β1 was able to stratify patients into high- and low-risk groups (PFS: 7.7 months vs. 15.5 months, P = 0.004). Multiplex analysis of patient plasma in this trial identified several baseline- and treatment-related biomarkers associated with clinical outcome. These findings merit further exploration in larger, controlled clinical trials.
    Cancer Medicine 04/2013; 2(2):234-42.
  • [Show abstract] [Hide abstract]
    ABSTRACT: BACKGROUND: Esophageal and gastric cancers often present at an advanced stage. Systemic chemotherapy is the mainstay of treatment, but survival with current regimens remains poor. We evaluated the safety, tolerability, and efficacy of the combination capecitabine, oxaliplatin, and bevacizumab in the treatment of metastatic esophagogastric adenocarcinomas. METHODS: Thirty-seven patients with metastatic or unresectable gastric/gastroesophageal junction tumors were enrolled and treated with capecitabine 850 mg/m(2) BID on days @-14, and oxaliplatin 130mg/m(2) with bevacizumab 15 mg/kg on day 1 of a 21-day cycle. The primary endpoint was progression-free survival (PFS). Secondary endpoints included response rate (RR) and overall survival (OS). Neuropilin-1 (NRP1) and -2 (NRP2)mRNAexpression was evaluated in archived tumor. RESULTS: Thirty-five patientswereevaluable for efficacy.MedianPFS was 7.2 months; median OS was 10.8 months. RR was estimated at 51.4%. The regimen was tolerable with expected drug class-related toxicities. NRP2 mRNA levels significantly correlated with PFS (p= 0.042) and showed a trend toward significance with OS (p=0.051). NonsignificanttrendsforNRP1werenotedforhigherexpressionlevels and worse outcome. CONCLUSIONS: Bevacizumab can be given safely with chemotherapy in patients with metastatic esophagogastric adenocarcinomas. The combinationofcapecitabine, oxaliplatin,plusbevacizumabhasactivitycomparable to other bevacizumab-containing regimens in metastatic gastroesophagealcancer.
    The Oncologist 03/2013; · 4.10 Impact Factor
  • Source
    Andrew Dellinger, Herbert Pang
    J Biomet Biostat. 01/2013;
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Introduction Standard therapy for limited stage small cell lung cancer (L-SCLC) is concurrent chemotherapy and radiotherapy followed by prophylactic cranial radiotherapy. Predictors of post chemoradiotherapy pulmonary toxicity in limited stage (LS) small cell lung cancer (SCLC) patients are not well defined. Current guidelines are derived from non-small cell lung cancer regimens, and do not account for the unique biology of this disease. Therefore, we analyzed patients on three consecutive CALGB LS-SCLC trials treated with concurrent chemotherapy and daily high dose radiotherapy (70 Gy) to determine patient and treatment related factors predicting for post-treatment pulmonary toxicity. Methods Patients treated on CALGB protocols 39808, 30002, 30206 investigating two cycles of chemotherapy followed by concurrent chemotherapy and 70 Gy daily thoracic radiation therapy were pooled. Patient, tumor, and treatment related factors were evaluated to determine predictors of grade 3–5 pulmonary toxicities after concurrent chemoradiotherapy. Results 100 patients were included. No patient experienced grade 4–5 post-treatment pulmonary toxicity. Patients who experienced post-treatment pulmonary toxicity were more likely to be older (median age 69 vs 60, p = 0.09) and have smaller total lung volumes (2565 cc vs 3530 cc, p = 0.05).). Furthermore, exposure of larger volumes of lung to lower (median V5 = 70%, p = 0.09, median V10 = 63%, p = 0.07), intermediate (median V20 = 50, p = 0.04) and high (median V60 = 25%, p = 0.01) doses of radiation were all associated with post-treatment grade 3 pulmonary toxicity, as was a larger mean lung radiation dose (median 31 Gy) p = 0.019. Conclusion Post-treatment pulmonary toxicity following the completion of 2 cycles of chemotherapy followed by concurrent chemotherapy and high dose daily radiation therapy was uncommon. Care should be taken to minimize mean lung radiation exposure, as well as volumes of low, intermediate and high doses of radiation.
    Lung Cancer. 01/2013; 82(3):436–440.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Introduction: Standard therapy for limited-stage small-cell lung cancer (L-SCLC) is concurrent chemotherapy and radiotherapy (RT) followed by prophylactic cranial radiotherapy. Although many consider the standard RT regimen to be 45 Gy in 1.5 Gy twice-daily fractions, this has failed to gain widespread acceptance. We pooled data of patients assigned to receive daily RT of 70 Gy from three, consecutive prospective Cancer and Leukemia Group B L-SCLC cancer trials and report the results here. Methods: All patients from consecutive Cancer and Leukemia Group B L-SCLC trials (39808, 30002, and 30206) using high-dosage daily RT with concurrent chemotherapy were included, and analyzed for toxicity, disease control, and survival. Overall survival (OS) and progression-free survival (PFS) were modeled using Cox proportional hazards models. Prognostic variables for OS-rate and PFS-rate were assessed using logistic regression model. Results: Two hundred patients were included. The median follow-up was 78 months. Grade 3 or greater esophagitis was 23%. The median OS for pooled population was 19.9 months (95% confidence interval [CI]: 16.7–22.3), and 5-year OS rate was 20% (95% CI: 16–27%). The 2-year PFS was 26% (95% CI: 21–32%). Multivariate analysis found younger age (p = 0.02; hazard ratio [HR]: 1.023; 95% CI: 21-32), and female sex (p = 0.02; HR:0.69; 95% CI: 0.50-0.94) independently associated with improved overall survival. Conclusion: Two-Gy daily RT to a total dosage of 70 Gy was well tolerated with similar survival to 45 Gy (1.5 Gy twice-daily). This experience may aid practitioners decide whether high-dosage daily RT with platinum-based chemotherapy is appropriate outside of a clinical trial.
    Journal of Thoracic Oncology 01/2013; 8(8):1043-1049. · 4.47 Impact Factor

Publication Stats

328 Citations
240.87 Total Impact Points

Institutions

  • 2014
    • The University of Hong Kong
      Hong Kong, Hong Kong
  • 2009–2014
    • Duke University Medical Center
      • • Department of Medicine
      • • Department of Biostatistics and Bioinformatics
      Durham, North Carolina, United States
  • 2012–2013
    • Duke University
      • Department of Medicine
      Durham, North Carolina, United States
    • Virginia Polytechnic Institute and State University
      • Department of Statistics
      Blacksburg, VA, United States
  • 2010
    • The Ohio State University
      Columbus, Ohio, United States
  • 2008
    • Stowers Institute for Medical Research
      Kansas City, Kansas, United States
    • Yale University
      • Department of Biostatistics
      New Haven, CT, United States
  • 2006–2008
    • Yale-New Haven Hospital
      New Haven, Connecticut, United States