Publications by authors named "Paul N M Cheng"

Diabetic retinopathy (DR) is a serious complication of diabetes that results from sustained hyperglycemia, hyperlipidemia, and oxidative stress. Under these conditions, inducible nitric oxide synthase (iNOS) expression is upregulated in the macrophages (MΦ) and microglia, resulting in increased production of reactive oxygen species (ROS) and inflammatory cytokines, which contribute to disease progression. Arginase 1 (Arg1) is a ureohydrolase that competes with iNOS for their common substrate, L-arginine.

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Introduction: We investigated the safety and efficacy of a pegylated arginase (PEG-BCT-100) in combination with chemotherapy (oxaliplatin and capecitabine) [PACOX] in advanced HCC patients.

Methods: This was a single centre phase 1 trial to assess the safety and tolerability of PACOX. All the enrolled subjects received treatment in 3-weekly cycles: intravenous PEG-BCT-100 2.

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Background The study determined the safety, pharmacokinetics/pharmacodynamics (PK/PD), and recommended Phase II dose of BCT-100 for arginine auxotrophic tumours in a non-Chinese population. Methods This is a Phase I, 3 + 3 dose-escalation, open-label, multi-centre study in two arginine auxotrophic cancers-Malignant Melanoma (MM) and Castration Resistant Prostate Cancer (CRPC). Patients were enrolled to receive weekly intravenous BCT-100.

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Background: Pegylated recombinant human arginase (PEG-BCT-100) is an arginine depleting drug. Preclinical studies showed that HCC is reliant on exogenous arginine for growth due to the under-expression of the arginine regenerating enzymes argininosuccinate synthetase (ASS) and ornithine transcarbamylase (OTC).

Methods: This is a single arm open-label Phase II trial to assess the potential clinical efficacy of PEG-BCT-100 in chemo naïve sorafenib-failure HCC patients.

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Hepatocellular carcinoma (HCC) is considered as auxotrophic for arginine and BCT-100, a new recombinant human arginase, has been synthesized for arginine deprivation to inhibit arginine-dependent tumor growth. The aim of the present study was to evaluate the effects of BCT-100 on the inhibition of in vitro cell proliferation of HCC cell lines and in vivo tumor growth. The molecular mechanism involved was also studied.

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Melanoma has been shown to require arginine for growth, thus providing a potential Achilles' heel for therapeutic exploitation. Our investigations show that arginine depletion, using a recombinant form of human arginase I (rhArg), efficiently inhibits the growth of mammalian melanoma cell lines in vitro. These cell lines are consistently deficient in ornithine transcarbamylase (OTC) expression, correlating with their sensitivity to rhArg.

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We describe a 75-year-old Chinese man who presented with three separate tumors in three different lobes of the lung, without evidence of mediastinal or systemic involvement. All three tumors were surgically resected by minimal invasive approach. Based on a differing epidermal growth factor receptor (EGFR) mutation status, the tumors were characterized as synchronous triple primary rather than intrapulmonary metastases.

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