Publications by authors named "Leo W K Cheung"

Purpose: Mutations in BTK, PLCG2, and BCL2 have been reported in patients with progressive disease (PD) on continuous single-agent BTK or BCL2 inhibitor treatment. We tested for these mutations in samples from patients with PD after completion of first-line treatment with fixed-duration ibrutinib plus venetoclax for chronic lymphocytic leukemia (CLL) in the phase II CAPTIVATE study.

Patients And Methods: A total of 191 patients completed fixed-duration ibrutinib plus venetoclax (three cycles of ibrutinib then 12-13 cycles of ibrutinib plus venetoclax).

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Purpose: Acquired mutations in Bruton's tyrosine kinase (BTK) or phospholipase C-γ2 (PLCG2) genes are associated with clinical progressive disease (PD) in patients with chronic lymphocytic leukemia (CLL) treated with BTK inhibitors. Data on mutation rates in patients without PD on ibrutinib treatment are limited.

Experimental Design: We evaluated frequency and time to detection of BTK and PLCG2 mutations in peripheral blood samples from 388 patients with previously untreated (n = 238) or relapsed/refractory (n = 150) CLL across five clinical trials.

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The Bruton's tyrosine kinase (BTK) inhibitor ibrutinib irreversibly binds BTK at Cys, inhibiting its kinase activity and thus blocking transduction of B cell receptor (BCR) signaling. Although ibrutinib is durably effective in patients with B cell malignancies, many patients still develop ibrutinib-resistant disease. Resistance can arise because of mutations at the ibrutinib-binding site in BTK.

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Genomic abnormalities, including del(17p)/ mutation, del(11q), unmutated IGHV, and mutations in , , , and predict poor outcomes with chemoimmunotherapy in chronic lymphocytic leukemia. To better understand the impact of these high-risk genomic features on outcomes with first-line ibrutinib-based therapy, we performed pooled analysis of two phase 3 studies with 498 patients randomized to receive ibrutinib- or chlorambucil-based therapy with median follow-up of 49.1 months.

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Anti-CD20 antibody treatments, such as obinutuzumab, have been associated with infusion-related reactions (IRRs). In the phase 3 iLLUMINATE study of ibrutinib-obinutuzumab versus chlorambucil-obinutuzumab in first-line chronic lymphocytic leukemia/small lymphocytic lymphoma, IRRs were substantially reduced with ibrutinib-obinutuzumab versus chlorambucil-obinutuzumab. We prospectively analyzed inflammatory cytokines to evaluate the impact of ibrutinib on circulating cytokine levels following obinutuzumab infusion.

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Advanced marginal zone lymphoma (MZL) is an incurable B-cell malignancy dependent on B-cell receptor signaling. The phase 2 PCYC-1121 study demonstrated the safety and efficacy of single-agent ibrutinib 560 mg/d in 63 patients with relapsed/refractory MZL treated with prior rituximab (RTX) or rituximab-based chemoimmunotherapy (RTX-CIT). We report the final analysis of PCYC-1121 with median follow-up of 33.

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Diffuse large B-cell lymphoma (DLBCL) and follicular lymphoma are the most prevalent B-lymphocyte neoplasms in which abnormal activation of the Bruton tyrosine kinase (BTK)-mediated B-cell receptor signaling pathway contributes to pathogenesis. Ibrutinib is an oral covalent BTK inhibitor that has shown some efficacy in both indications. To improve ibrutinib efficacy through combination therapy, we first investigated differential gene expression in parental and ibrutinib-resistant cell lines to better understand the mechanisms of resistance.

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Diet-related chronic diseases are at epidemic levels in low-income ethnic minority populations. The purpose of this study is to decrease risk for obesity in children by modifying the food environment and conducting point-of-purchase promotions that will lead to changes in psychosocial factors and behaviors associated with healthier food choices among low-income communities with a preponderance of Native Hawaiians and Pacific Islanders. We implemented an intervention trial over a 9-11-month period in five food stores in two low-income multiethnic communities in Hawaii, targeting both children and their adult caregivers.

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Progestogens appear to influence breast density more than estrogens in postmenopausal women taking hormone replacement therapy (HRT), but little is known about the effect of circulating hormones on mammographic density among premenopausal women. This cross-sectional study explores the relationship of body weight and sex steroids with breast density. Luteal serum samples were analyzed for progesterone, estrone, estradiol, and sex hormone-binding globulin (SHBG).

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