Publications by authors named "Harry A Drabkin"

Objective: Innate and acquired resistance is the principle factor limiting the efficacy of tyrosine kinase inhibitors in lung cancer. We have observed a dramatic upregulation of the cell surface co-receptor neuropilin-2b in lung cancers clinically treated with tyrosine kinase inhibitors correlating with acquired resistance. We hypothesize that neuropilin-2b plays a functional role in acquired tyrosine kinase inhibitor resistance.

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Lung cancer is the leading cause of cancer deaths worldwide. It is an aggressive and devastating cancer because of metastasis triggered by enhanced migration and invasion, and resistance to cytotoxic chemotherapy. The epithelial to mesenchymal transition (EMT) is a fundamental developmental process that is reactivated in wound healing and a variety of diseases including cancer where it promotes migration/invasion and metastasis, resistance to treatment, and generation and maintenance of cancer stem cells.

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Neuropilins (NRP1 and NRP2) are co-receptors for heparin-binding growth factors and class 3 semaphorins. Different isoforms of NRP1 and NRP2 are produced by alternative splicing. We found that in non-small cell lung cancer (NSCLC) cell lines, transforming growth factor-β (TGFβ) signaling preferentially increased the abundance of NRP2b.

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Background: Malignancy after transplantation is an uncommon multifactorial occurrence. Immunosuppression to prevent graft rejection is described as a major risk factor in malignancy development in the post-transplant state. Donor-derived malignancy is a rare reported complication.

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Background: Upregulation of sphingosine-1-phosphate (S1P) may mediate resistance to vascular endothelial growth factor (VEGF)-directed therapies and inhibit antitumor immunity. Antagonism of S1P in preclinical models appears to overcome this resistance. In this phase 2 study, the authors assessed the activity of sonepcizumab, a first-in-class inhibitor of S1P, in patients with metastatic renal cell carcinoma (mRCC) with a history of prior VEGF-directed therapy.

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Epithelial-mesenchymal transition (EMT) is one mechanism of acquired resistance to inhibitors of the epidermal growth factor receptor-tyrosine kinases (EGFR-TKIs) in non-small cell lung cancer (NSCLC). The precise mechanisms of EMT-related acquired resistance to EGFR-TKIs in NSCLC remain unclear. We generated erlotinib-resistant HCC4006 cells (HCC4006ER) by chronic exposure of EGFR-mutant HCC4006 cells to increasing concentrations of erlotinib.

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Introduction: Immune-based therapies (e.g., IL-2, IFN) have been used for some time in advanced clear cell renal cell carcinoma (RCC) with overall modest success.

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Background: Although distinct patterns of homeobox (HOX) gene expression have been described in defined cytogenetic and molecular subsets of patients with acute myeloid leukemia (AML), it is unknown whether these patterns are the direct result of transcriptional alterations or rather represent the differentiation stage of the leukemic cell.

Method: To address this question, we used qPCR to analyze mRNA expression of HOXA and HOXB genes in bone marrow (BM) samples of 46 patients with AML and sorted subpopulations of healthy BM cells. These various stages of myeloid differentiation represent matched counterparts of morphological subgroups of AML.

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Purpose: Nivolumab is a fully human immunoglobulin G4 programmed death-1 immune checkpoint inhibitor antibody that restores T-cell immune activity. This phase II trial assessed the antitumor activity, dose-response relationship, and safety of nivolumab in patients with metastatic renal cell carcinoma (mRCC).

Patients And Methods: Patients with clear-cell mRCC previously treated with agents targeting the vascular endothelial growth factor pathway were randomly assigned (blinded ratio of 1:1:1) to nivolumab 0.

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The semaphorins, discovered over 20 years ago, are a large family of secreted or transmembrane and glycophosphatidylinositol -anchored proteins initially identified as axon guidance molecules crucial for the development of the nervous system. It has now been established that they also play important roles in organ development and function, especially involving the immune, respiratory, and cardiovascular systems, and in pathological disorders, including cancer. During tumor progression, semaphorins can have both pro- and anti-tumor functions, and this has created complexities in our understanding of these systems.

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It has emerged that palindrome-mediated genomic instability generates DNA-based rearrangements. The presence of palindromic AT-rich repeats (PATRRs) at the translocation breakpoints suggested a palindrome-mediated mechanism in the generation of several recurrent constitutional rearrangements: the t(11;22), t(17;22), and t(8;22). To date, all reported PATRR-mediated translocations include the PATRR on chromosome 22 (PATRR22) as a translocation partner.

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Background: DNA aptamers represent a novel strategy in anti-cancer medicine. AS1411, a DNA aptamer targeting nucleolin (a protein which is overexpressed in many tumor types), was evaluated in patients with metastatic, clear-cell, renal cell carcinoma (RCC) who had failed treatment with ≥1 prior tyrosine kinase inhibitor.

Methods: In this phase II, single-arm study, AS1411 was administered at 40 mg/kg/day by continuous intravenous infusion on days 1-4 of a 28-day cycle, for two cycles.

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The epithelial-mesenchymal transition (EMT) and its reversal, mesenchymal-epithelial transition (MET), are fundamental processes involved in tumor cell invasion and metastasis. SEMA3F is a secreted semaphorin and tumor suppressor downregulated by TGF-β1 and ZEB1-induced EMT. Here, we report that neuropilin (NRP)-2, the high-affinity receptor for SEMA3F and a coreceptor for certain growth factors, is upregulated during TGF-β1-driven EMT in lung cancer cells.

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We experimentally demonstrate label-free photonic crystal (PC) microcavity biosensors in silicon-on-insulator (SOI) to detect the epithelial-mesenchymal transition (EMT) transcription factor, ZEB1, in minute volumes of sample. Multiplexed specific detection of ZEB1 in lysates from NCI-H358 lung cancer cells down to an estimated concentration of 2 cells per micro-liter is demonstrated. L13 photonic crystal microcavities, coupled to W1 photonic crystal waveguides, are employed in which resonances show high Q in the bio-ambient phosphate buffered saline (PBS).

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The majority of kidney cancers are clear-cell carcinomas (ccRCC), characterized by the accumulation of cholesterol, cholesterol esters, other neutral lipids and glycogen. Rather than being a passive bystander, the clear-cell phenotype is suggested to be a biomarker of deregulated cholesterol and lipid biosynthesis, which plays an important role in development of the disease. One clue to this relationship has come from the elucidation of the hereditary kidney cancer gene, TRC8, which functions partly to degrade key regulators of endogenous cholesterol and lipid biosynthesis.

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Purpose: Combining proteasome and histone deacetylase (HDAC) inhibition has been seen to provide synergistic anti-tumor activity, with complementary effects on a number of signaling pathways. The novel bi-cyclic structure of marizomib with its unique proteasome inhibition, toxicology and efficacy profiles, suggested utility in combining it with an HDAC inhibitor such as vorinostat. Thus, in this study in vitro studies assessed the potential utility of combining marizomib and vorinostat, followed by a clinical trial with the objectives of assessing the recommended phase 2 dose (RP2D), pharmacokinetics (PK), pharmacodynamics (PD), safety and preliminary anti-tumor activity of the combination in patients.

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Background: The nucleoporin gene NUP98 is rearranged in more than 27 chromosomal abnormalities observed in childhood and adult, de novo and therapy-related acute leukemias of myeloid and T-lymphoid origins, resulting in the creation of fusion genes and the expression of chimeric proteins. We report here the functional analysis of the NUP98-coiled-coil domain-containing protein 28A (NUP98-CCDC28A) fusion protein, expressed as the consequence of a recurrent t(6;11)(q24.1;p15.

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Background: Activating mutations in fms-like tyrosine kinase-3 (FLT3) are frequent in acute myeloid leukemia and represent both a poor prognostic feature and a therapeutic target. We have identified a previously unrecognized downstream effect of FLT3 activation, namely up-regulation of the homeodomain genes, DLX1 and DLX2.

Design And Methods: MV4;11 cells with FLT3-internal tandem duplication mutation, RS4;11 cells with wild-type FLT3 and blasts from patients with acute myeloid leukemia were used to pursue the relation between FLT3, DLX1/2 and transforming growth factor-β (TGFβ).

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The epithelial to mesenchymal transition (EMT) is a developmental process enabling epithelial cells to gain a migratory mesenchymal phenotype. In cancer, this process contributes to metastases; however the regulatory signals and mechanistic details are not fully elucidated. Here, we sought to identify the subset of genes regulated in lung cancer by ZEB1, an E-box transcriptional repressor known to induce EMT.

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Objective: In this retrospective analysis of the Advanced Renal Cell Carcinoma Sorafenib (ARCCS) program in North America, we compared the safety and efficacy of sorafenib in patients aged ≥70 with those aged <70 years.

Methods: Patients were treated with oral sorafenib twice daily until the occurrence of disease progression or treatment intolerance. The primary objective of the ARCCS program was making sorafenib available to patients with advanced renal cell carcinoma (RCC) in the USA and Canada before marketing approval was obtained; the secondary objective was the evaluation of its safety and efficacy.

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Palindrome-mediated genomic instability has been associated with chromosomal translocations, including the recurrent t(11;22)(q23;q11). We report a syndrome characterized by extremity anomalies, mild dysmorphia, and intellectual impairment caused by 3:1 meiotic segregation of a previously unrecognized recurrent palindrome-mediated rearrangement, the t(8;22)(q24.13;q11.

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Background: HOX genes play an important role in both normal lymphopoiesis and leukemogenesis. However, HOX expression patterns in leukemia cells compared to normal lymphoid progenitors have not been systematically studied in acute lymphoblastic leukemia (ALL) subtypes.

Procedure: The RNA expression levels of HOXA, HOXB, and CDX1/2 genes were analyzed by qRT-PCR in a cohort of 61 diagnostic pediatric ALL samples and FACS-sorted subpopulations of normal lymphoid progenitors.

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Multiple epidemiologic studies have linked the development of renal cancer to obesity. In this chapter, we begin with a review of selected population studies, followed by recent mechanistic discoveries that further link lipid deregulation to the RCC development. The upregulation of leptin and downregulation of adiponectin pathways in obesity fit well with our molecular understanding of RCC pathogenesis.

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Background: The Advanced Renal Cell Carcinoma Sorafenib (ARCCS) program made sorafenib available to patients with advanced renal cell carcinoma (RCC) before regulatory approval.

Methods: In this nonrandomized, open-label expanded access program, 2504 patients from the United States and Canada were treated with oral sorafenib 400 mg twice daily. Safety and efficacy were explored overall and in subgroups of patients including those with no prior therapy, nonclear cell (nonclear cell) RCC, brain metastases, prior bevacizumab treatment, and elderly patients.

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