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1.  Identification of Predictive Markers of Response to the MEK1/2 Inhibitor Selumetinib (AZD6244) in K-ras–Mutated Colorectal Cancer 
Molecular cancer therapeutics  2010;9(12):3351-3362.
Mutant K-ras activity leads to the activation of the RAS/RAF/MEK/ERK pathway in approximately 44% of colorectal cancer (CRC) tumors. Accordingly, several inhibitors of the MEK pathway are under clinical evaluation in several malignancies including CRC. The aim of this study was to develop and characterize predictive biomarkers of response to the MEK1/2 inhibitor AZD6244 in CRC in order to maximize the clinical utility of this agent. Twenty-seven human CRC cell lines were exposed to AZD6244 and classified according to the IC50 value as sensitive (≤0.1 µmol/L) or resistant (>1 µmol/L). All cell lines were subjected to immunoblotting for effector proteins, K-ras/BRAF mutation status, and baseline gene array analysis. Further testing was done in cell line xenografts and K-ras mutant CRC human explants models to develop a predictive genomic classifier for AZD6244. The most sensitive and resistant cell lines were subjected to differential gene array and pathway analyses. Members of the Wnt signaling pathway were highly overexpressed in cell lines resistant to AZD6244 and seem to be functionally involved in mediating resistance by shRNA knockdown studies. Baseline gene array data from CRC cell lines and xenografts were used to develop a k-top scoring pair (k-TSP) classifier, which predicted with 71% accuracy which of a test set of patient-derived K-ras mutant CRC explants would respond to AZD6244, providing the basis for a patient-selective clinical trial. These results also indicate that resistance to AZD6244 may be mediated, in part, by the upregulation of the Wnt pathway, suggesting potential rational combination partners for AZD6244 in CRC.
doi:10.1158/1535-7163.MCT-10-0376
PMCID: PMC3931013  PMID: 20923857
2.  Patient-derived tumour xenografts as models for oncology drug development 
Progress in oncology drug development has been hampered by a lack of preclinical models that reliably predict clinical activity of novel compounds in cancer patients. In an effort to address these shortcomings, there has been a recent increase in the use of patient-derived tumour xenografts (PDTX) engrafted into immune-compromised rodents such as athymic nude or NOD/SCID mice for preclinical modelling. Numerous tumour-specific PDTX models have been established and, importantly, they are biologically stable when passaged in mice in terms of global gene-expression patterns, mutational status, metastatic potential, drug responsiveness and tumour architecture. These characteristics might provide significant improvements over standard cell-line xenograft models. This Review will discuss specific PDTX disease examples illustrating an overview of the opportunities and limitations of these models in cancer drug development, and describe concepts regarding predictive biomarker development and future applications.
doi:10.1038/nrclinonc.2012.61
PMCID: PMC3928688  PMID: 22508028
3.  A phase 1, open-label, dose-escalation study of BIIB022 (anti-IGF-1R monoclonal antibody) in subjects with relapsed or refractory solid tumors 
Investigational New Drugs  2014;32:518-525.
Summary
Purpose The IGF-1R signaling pathway has been implicated in multiple cancers as important for cell survival, proliferation, invasion and metastasis. BIIB022 is a non-glycosylated human IgG4 monoclonal antibody (mAb) with specificity for IGF-1R. Unlike other anti-IGF1R antibodies, BIIB022 has no effector functions. Additionally, inhibition is via an allosteric rather than competitive mechanism, which further differentiates this antibody from others. We sought to determine the safety and tolerability of BIIB022 and determine the pharmacokinetic (PK) and pharmacodynamic (PD) profile of this antibody. Methods A multi-institutional phase I study evaluated the safety of escalating doses of BIIB022 given IV q3wk until progression or unacceptable toxicity in patients with advanced solid tumors. Five sequential BIIB022 dose cohorts were evaluated using a standard 3 + 3 dose-escalation design (1.5, 5. 10, 20, 30 mg/kg); 10 additional patients were treated at the recommended phase 2 dose. Results 34 patients were treated. Toxicities were manageable and mostly low grade; grade 3–4 hyperglycemia was not observed. No RECIST responses were observed, although three patients had metabolic responses associated with prolonged stable disease. The PK of BIIB022 was nearly linear in the dose range from 10 to 30 mg/kg, with some nonlinearity at lower doses (1.5–5.0 mg/kg), likely due to target-mediated drug disposition of BIIB022 at low serum concentrations. PD analyses showed decrease in IGF-1R levels on leucocytes, with stable serum values of IGF-1 and IGF-2. Conclusions BIIB022 can be safely given at 30 mg/kg IV every 3 weeks with preliminary evidence of biological activity in selected patients.
doi:10.1007/s10637-014-0064-y
PMCID: PMC4045341  PMID: 24458261
IGF-1R; Antibody; Phase I; Sarcoma; FDG-PET
4.  From Bench to Bedside: Lessons Learned in Translating Preclinical Studies in Cancer Drug Development 
The development of targeted agents in oncology has rapidly expanded over the past 2 decades and has led to clinically significant improvements in the treatment of numerous cancers. Unfortunately, not all success at the bench in preclinical experiments has translated to success at the bedside. As preclinical studies shift toward defining proof of mechanism, patient selection, and rational drug combinations, it is critical to understand the lessons learned from prior translational studies to gain an understanding of prior drug development successes and failures. By learning from prior drug development, future translational studies will provide more clinically relevant data, and the underlying hope is that the clinical success rate will improve and the treatment of patients with ineffective targeted therapy will be limited.
doi:10.1093/jnci/djt209
PMCID: PMC3787906  PMID: 24052618
5.  Elevated Gene Expression in Chalcone Synthase Enzyme Suggests an Increased Production of Flavonoids in Skin and Synchronized Red Cell Cultures of North American Native Grape Berries 
DNA and Cell Biology  2012;31(6):939-945.
Anthocyanins are antioxidants and are among the natural products synthesized via the flavonoid biosynthesis pathway. Anthocyanins have been recommended for dietary intake in the prevention of cardiovascular diseases, cancer, and age-related conditions such as Alzheimer's disease or dementia. With an increasingly aging population in many parts of the world, strategies for the commercial production of in vitro synchronized red cell cultures as natural antioxidants will be a significant contribution to human medicine. Red pigmented fruits such as grapes (Vitis sp.) are a major source of bioavailable anthocyanins and other polyphenols. Since the level of antioxidants varies among cultivars, this study is the first one that phytochemically and genetically characterizes native grape cultivars of North America to determine the optimal cultivar and berry cells for the production of anthocyanins as antioxidants. Using real-time PCR and bioinformatics approaches, we tested for the transcript expression of the chalcone synthase (CHS) gene, an enzyme involved in the flavonoid and anthocyanin biosynthesis pathway, in different parts of physiologically mature grape berries and in vitro synchronized red cells. A low level of expression was recorded in berry flesh, compared with an elevated expression in berry skins and in vitro synchronized red cells, suggesting increased production of flavonoids in skin and cell cultures. This preliminary study demonstrates the potential of functional genomics in natural products research as well as in systematic studies of North American native grapes, specifically in muscadine (Vitis rotundifolia).
doi:10.1089/dna.2011.1589
PMCID: PMC3378974  PMID: 22364203
6.  Impacts of Horticultural Mineral Oils and Two Insecticide Practices on Population Fluctuation of Diaphorina citri and Spread of Huanglongbing in a Citrus Orchard in Sarawak 
The Scientific World Journal  2012;2012:651416.
Aspects of the incidence and spread of the citrus disease huanglongbing (HLB) in relation to the vector Diaphorina citri population fluctuation were studied from January 1999 to December 2001 seasons in a 0.8 ha citrus orchard at Jemukan (1° 33′N, 110° 41′E), Southwest Sarawak in Malaysia. In relation to insecticide and horticultural mineral oils (HMOs) use, levels of HLB infection rose quite rapidly over the next 3 years in the unsprayed control and less rapidly in the other treatments such as imidacloprid, nC24HMO, and triazophos/cypermethrin/chlorpyrifos. Levels of HLB as determined by Polymerase Chain Reaction (PCR) were 42.2%, 9.4%, 11.4%, and 22.7%, respectively. The effects of nC24HMO and conventional pesticides on the citrus psyllid population and parasitoids in citrus orchard were also determined.
doi:10.1100/2012/651416
PMCID: PMC3354681  PMID: 22629178
7.  Seasonal Abundance and Suppression of Fruit-Piercing Moth Eudocima phalonia (L.) in a Citrus Orchard in Sarawak 
TheScientificWorldJournal  2011;11:2330-2338.
Seasonal population of the fruit-piercing moths Eudocima spp. was monitored throughout the citrus growing seasons in a citrus orchard and in site adjacent to secondary forest from July 2007 to June 2009. The moth was detected practically throughout the year with activity lowest during the wet months (September-February) when fruits are still available and while highest during the dry months (May-June) which also coincided with the main fruiting season. The effects of an nC24 horticultural mineral oil (HMO) on the citrus fruit damage caused by fruit-piecing moths was also determined. The percent fruit damage was significantly lowest (P≤0.05) in HMO-treated plots (8.4), followed by Dimethoate-treated plots (11.6) and untreated plots (22.5). However, there was no significant difference between HMO and Dimethoate treated plots indicating HMO is effective in reducing percent fruit damage.
doi:10.1100/2011/753484
PMCID: PMC3236462  PMID: 22203789
Fruit-piercing moth; seasonal population; citrus fruit damage; nC24 horticultural mineral oil; conventional pesticide.
8.  The IGF-1R/IR Tyrosine Kinase Inhibitor, PQIP, Exhibits Enhanced Anti-Tumor Effects in Combination with Chemotherapy Against Colorectal Cancer Models 
Purpose
There is growing evidence implicating the importance of the insulin-like growth factor (IGF) pathway in colorectal cancer (CRC) based upon the results of population studies, and preclinical experiments. However, the combination of an IGF-1 receptor (IGF-1R) inhibitor with standard CRC chemotherapies has not yet been evaluated. In this study, we investigated the interaction between the dual IGF-1R/IR tyrosine kinase inhibitor (TKI), PQIP, and standard chemotherapies in CRC cell line models.
Experimental Design
The antiproliferative effects of PQIP, as a single agent and in combination with 5-fluorouracil, oxaliplatin, or SN38 were analyzed against four CRC cell lines. Downstream effector proteins, apoptosis and cell cycle were also assessed in the combination of PQIP and SN-38. Lastly, the efficacy of OSI-906 (a derivative of PQIP) combined with irinotecan was further tested using a human CRC xenograft model.
Results
Treatment with the combination of PQIP and each of three chemotherapies resulted in an enhanced decrease in proliferation of all four colorectal cancer cell lines compared to single agent treatment. This inhibition was not associated with a significant induction of apoptosis, but was accompanied by cell cycle arrest and changes in phosphorylation of Akt. Interestingly, antitumor activity between PQIP and SN-38 in vitro was also reflected in the human CRC xenograft model.
Conclusions
Combination treatment with the dual IGF-1R/IR TKI, PQIP, and standard CRC chemotherapy resulted in enhanced antiproliferative effects against CRC cell line models providing a scientific rationale for the testing of OSI-906 and standard CRC treatment regimens.
doi:10.1158/1078-0432.CCR-10-2054
PMCID: PMC3119523  PMID: 20943761
9.  Development of an Integrated Genomic Classifier for a Novel Agent in Colorectal Cancer: Approach to Individualized Therapy in Early Development 
Background
A plethora of agents are in early stages of development for colorectal cancer, including those that target the insulin-like growth factor receptor (IGF1R) pathway. In the current environment of numerous cancer targets, it is imperative that patient selection strategies be developed with the intent of preliminary testing in the latter stages of phase I trials. The goal of this study was to develop and characterize predictive biomarkers for an IGF1R tyrosine kinase inhibitor, OSI-906, that could be applied in colorectal cancer (CRC)-specific studies of this agent.
Methods
Twenty-seven CRC cell lines were exposed to OSI-906 and classified according to IC50 value as sensitive (< 1.5μM), or resistant (>5μM). Cell lines were subjected to immunoblotting and immunohistochemistry for effector proteins, IGFIR copy number by FISH, KRAS/BRAF/PI3K mutation status, and baseline gene array analysis. The most sensitive and resistant cell lines were utilized for gene array and pathway analyses, along with shRNA knockdown of highly ranked genes. The resulting integrated genomic classifier was then tested against 8 human CRC explants in vivo.
Results
Baseline gene array data from cell lines and xenografts was used to develop a k-Top Scoring Pair (k-TSP) classifier, which in combination with IGFIR FISH and KRAS mutational status, was able to predict with 100% accuracy a test set of patient-derived CRC xenografts.
Conclusions
These results indicate that an integrated approach to the development of individualized therapy is feasible and should be applied early in the development of novel agents, ideally in conjunction with late-stage phase I trials.
doi:10.1158/1078-0432.CCR-09-3191
PMCID: PMC2889230  PMID: 20530704
10.  Phase I Pharmacologic and Biologic Study of Ramucirumab (IMC-1121B), a Fully Human Immunoglobulin G1 Monoclonal Antibody Targeting the Vascular Endothelial Growth Factor Receptor-2 
Journal of Clinical Oncology  2010;28(5):780-787.
Purpose
To evaluate the safety, maximum-tolerated dose (MTD), pharmacokinetics (PKs), pharmacodynamics, and preliminary anticancer activity of ramucirumab (IMC-1121B), a fully human immunoglobulin G1 monoclonal antibody targeting the vascular endothelial growth factor receptor (VEGFR)-2.
Patients and Methods
Patients with advanced solid malignancies were treated once weekly with escalating doses of ramucirumab. Blood was sampled for PK studies throughout treatment. The effects of ramucirumab on circulating vascular endothelial growth factor-A (VEGF-A), soluble VEGFR-1 and VEGFR-2, tumor perfusion, and vascularity using dynamic contrast-enhanced magnetic resonance imaging were assessed.
Results
Thirty-seven patients were treated with 2 to 16 mg/kg of ramucirumab. After one patient each developed dose-limiting hypertension and deep venous thrombosis at 16 mg/kg, the next lower dose (13 mg/kg) was considered the MTD. Nausea, vomiting, headache, fatigue, and proteinuria were also noted. Four (15%) of 27 patients with measurable disease had a partial response (PR), and 11 (30%) of 37 patients had either a PR or stable disease lasting at least 6 months. PKs were characterized by dose-dependent elimination and nonlinear exposure consistent with saturable clearance. Mean trough concentrations exceeded biologically relevant target levels throughout treatment at all dose levels. Serum VEGF-A increased 1.5 to 3.5 times above pretreatment values and remained in this range throughout treatment at all dose levels. Tumor perfusion and vascularity decreased in 69% of evaluable patients.
Conclusion
Objective antitumor activity and antiangiogenic effects were observed over a wide range of dose levels, suggesting that ramucirumab may have a favorable therapeutic index in treating malignancies amenable to VEGFR-2 inhibition.
doi:10.1200/JCO.2009.23.7537
PMCID: PMC2834394  PMID: 20048182
11.  Phase I Pharmacokinetic and Pharmacodynamic Study of the Oral, Small-Molecule Mitogen-Activated Protein Kinase Kinase 1/2 Inhibitor AZD6244 (ARRY-142886) in Patients With Advanced Cancers 
Purpose
To assess the tolerability, pharmacokinetics (PKs), and pharmacodynamics (PDs) of the mitogen-activated protein kinase kinase (MEK) 1/2 inhibitor AZD6244 (ARRY-142886) in patients with advanced cancer.
Patients and Methods
In part A, patients received escalating doses to determine the maximum-tolerated dose (MTD). In both parts, blood samples were collected to assess PK and PD parameters. In part B, patients were stratified by cancer type (melanoma v other) and randomly assigned to receive the MTD or 50% MTD. Biopsies were collected to determine inhibition of ERK phosphorylation, Ki-67 expression, and BRAF, KRAS, and NRAS mutations.
Results
Fifty-seven patients were enrolled. MTD in part A was 200 mg bid, but this dose was discontinued in part B because of toxicity. The 50% MTD (100 mg bid) was well tolerated. Rash was the most frequent and dose-limiting toxicity. Most other adverse events were grade 1 or 2. The PKs were less than dose proportional, with a median half-life of approximately 8 hours and inhibition of ERK phosphorylation in peripheral-blood mononuclear cells at all dose levels. Paired tumor biopsies demonstrated reduced ERK phosphorylation (geometric mean, 79%). Five of 20 patients demonstrated ≥ 50% inhibition of Ki-67 expression, and RAF or RAS mutations were detected in 10 of 26 assessable tumor samples. Nine patients had stable disease (SD) for ≥ 5 months, including two patients with SD for 19 (thyroid cancer) and 22 (uveal melanoma plus renal cancer) 28-day cycles.
Conclusion
AZD6244 was well tolerated with target inhibition demonstrated at the recommended phase II dose. PK analyses supported twice-daily dosing. Prolonged SD was seen in a variety of advanced cancers. Phase II studies are ongoing.
doi:10.1200/JCO.2007.14.4956
PMCID: PMC2718422  PMID: 18390968

Results 1-11 (11)