David Chan

Dr. David Chan

Department of Obstetrics & Gynaecology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
orcid

Research Focus & Metrics

Academic Career Length

32Years (1995-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 February 2021 in Autophagy
Verified
Journal Article
Closed access
DKDaniel J. Klionsky
Daniel J. Klionsky
AAAmal Kamal Abdel-Aziz
Amal Kamal Abdel-Aziz
SASara Abdelfatah
Sara Abdelfatah
MAMahmoud Abdellatif
Mahmoud Abdellatif
AAAsghar Abdoli
Asghar Abdoli
CTChun-Kit Tong
Chun-Kit Tong

Verified
Journal Article
Open access
PDF file
RZRuiqian Zhang
Ruiqian Zhang
MSMichelle K. Y. Siu
Michelle K. Y. Siu
HNHextan Yuen-Sheung Ngan
Hextan Yuen-Sheung Ngan
KCKaren KL Chan
Karen KL Chan
Ovarian cancer is the deadliest gynecological cancer, leading to over 152,000 deaths each year. A late diagnosis is the primary factor causing a poor prognosis of ovarian cancer and often occurs due to a lack of specific symptoms and effective biomarkers for an early detection. Currently, cancer antigen 125 (CA125) is the most widely used biomarker for ovarian cancer detection, but this approach is limited by a low specificity. In recent years, multimarker panels have been developed by combining molecular biomarkers such as human epididymis secretory protein 4 (HE4), ultrasound results, or menopausal status to improve the diagnostic efficacy. The risk of ovarian malignancy algorithm (ROMA), the risk of malignancy index (RMI), and OVA1 assays have also been clinically used with improved sensitivity and specificity. Ongoing investigations into novel biomarkers such as autoantibodies, ctDNAs, miRNAs, and DNA methylation signatures continue to aim to provide earlier detection methods for ovarian cancer. This paper reviews recent advancements in molecular biomarkers for the early detection of ovarian cancer.

1 January 2022 in Theranostics
Verified
Journal Article
Open access
YXYang Xuan
Yang Xuan
HWHuogang Wang
Huogang Wang
MYMingo M H Yung
Mingo M H Yung
FCFushun Chen
Fushun Chen
WCWai-Sun Chan
Wai-Sun Chan
David ChanDavid Chan
David Chan
Rationale: Malignant ascites in peritoneal metastases is a lipid-enriched microenvironment and is frequently involved in the poor prognosis of epithelial ovarian cancer (EOC). However, the detailed mechanisms underlying ovarian cancer (OvCa) cells dictating their lipid metabolic activities in promoting tumor progression remain elusive.

Verified
Journal Article
Open access
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HWHuogang Wang
Huogang Wang
MYMingo Ming Ho YUNG
Mingo Ming Ho YUNG
HNHextan Yuen-Sheung Ngan
Hextan Yuen-Sheung Ngan
KCKaren KL Chan
Karen KL Chan
David ChanDavid Chan
David Chan
Rather than primary solid tumors, metastasis is one of the hallmarks of most cancer deaths. Metastasis is a multistage event in which cancer cells escape from the primary tumor survive in the circulation and disseminate to distant sites. According to Stephen Paget’s “Seed and Soil” hypothesis, metastatic capacity is determined not only by the internal oncogenic driving force but also by the external environment of tumor cells. Throughout the body, macrophages are required for maintaining tissue homeostasis, even in the tumor milieu. To fulfill these multiple functions, macrophages are polarized from the inflammation status (M1-like) to anti-inflammation status (M2-like) to maintain the balance between inflammation and regeneration. However, tumor cell-enforced tumor-associated macrophages (TAMs) (a high M2/M1 ratio status) are associated with poor prognosis for most solid tumors, such as ovarian cancer. In fact, clinical evidence has verified that TAMs, representing up to 50% of the tumor mass, exert both protumor and immunosuppressive effects in promoting tumor metastasis through secretion of interleukin 10 (IL10), transforming growth factor β (TGFβ), and VEGF, expression of PD-1 and consumption of arginine to inhibit T cell anti-tumor function. However, the underlying molecular mechanisms by which the tumor microenvironment favors reprogramming of macrophages to TAMs to establish a premetastatic niche remain controversial. In this review, we examine the latest investigations of TAMs during tumor development, the microenvironmental factors involved in macrophage polarization, and the mechanisms of TAM-mediated tumor metastasis. We hope to dissect the critical roles of TAMs in tumor metastasis, and the potential applications of TAM-targeted therapeutic strategies in cancer treatment are discussed.

1 June 1998 in Arthritis & Rheumatism
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Journal Article
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CMChi Chiu Mok
Chi Chiu Mok
JLJerry S. Lanchbury
Jerry S. Lanchbury
David ChanDavid Chan
David Chan
CLChak Sing Lau
Chak Sing Lau
Objective To study the genetic association of interleukin‐10 (IL‐10) promoter polymorphisms in Southern Chinese patients with systemic lupus erythematosus (SLE), and to investigate possible associations with clinical manifestations of the disease. Methods DNA was extracted from 88 Chinese patients with SLE and 83 ethnically matched controls. The IL‐10 promoter region between positions ‐533 and ‐1120 was amplified by polymerase chain reaction, and polymorphisms were detected by restriction‐enzyme cleavage. Results No significant difference in the allele or haplotype frequencies between SLE patients and controls could be demonstrated. The *A and *C alleles at the ‐597 position were linked to the *T and *C alleles at the ‐824 position, respectively. However, when clinical features were examined, the *A allele at the ‐597 position and the *T allele at the ‐824 position were significantly associated with lupus nephritis, by chi‐square analysis (P < 0.001, odds ratio 4.19, 95% confidence interval 2.02‐8.71). Similarly, the haplotype ‐1087*A/‐824*T/‐597*A was also associated with renal involvement (P < 0.001, odds ratio 3.62, 95% confidence interval 1.80‐7.31). Conclusion IL‐10 promoter polymorphisms are not strong determinants of susceptibility to the development of SLE, per se, in Southern Chinese individuals. However, IL‐10 genotypes are strongly associated with certain clinical manifestations of SLE and may have a role in predicting disease prognosis.

16 June 2008 in Carcinogenesis
Verified
Journal Article
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David ChanDavid Chan
David Chan
VLVincent W.S. Liu
Vincent W.S. Liu
GTGeorge S.W. Tsao
George S.W. Tsao
KYKwok-Ming Yao
Kwok-Ming Yao
TFToru Furukawa
Toru Furukawa
HNHextan Yuen-Sheung Ngan
Hextan Yuen-Sheung Ngan
The RAS-RAF-MEK-extracellular signal-regulated kinase (ERK) pathway plays a pivotal role in various cellular responses, including cellular growth, differentiation, survival and motility. Constitutive activation of the ERK pathway has been linked to the development and progression of human cancers. Here, we reported that mitogen-activated protein kinase phosphatase (MKP)-3, a negative regulator of ERK1/2, lost its expression particularly in the protein level, was significantly correlated with high ERK1/2 activity in primary human ovarian cancer cells using quantitative reverse transcription–polymerase chain reaction and western blot analyses. Intriguingly, the loss of MKP3 protein was associated with ubiquitination/proteosome degradation mediated by high intracellular reactive oxygen species (ROS) accumulation such as hydrogen peroxide in ovarian cancer cells. Functionally, short hairpin RNA knock down of endogenous MKP3 resulted in increased ERK1/2 activity, cell proliferation rate, anchorage-independent growth ability and resistance to cisplatin in ovarian cancer cells. Conversely, enforced expression of MKP3 in MKP3-deficient ovarian cancer cells significantly reduced ERK1/2 activity and inhibited cell proliferation, anchorage-independent growth ability and tumor development in nude mice. Furthermore, the enforced expression of MKP3 succeeded to sensitize ovarian cancer cells to cisplatin-induced apoptosis in vitro and in vivo . These results suggest a molecular mechanism by which the accumulation of ROS during ovarian cancer progression may cause the degradation of MKP3, which in turn leads to aberrant ERK1/2 activation and contributes to tumorigenicity and chemoresistance of human ovarian cancer cells.