Tak Hong Cheung

Tak Hong Cheung


Research Focus & Metrics

Academic Career Length

31Years (1996-Present)

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

Representative Publications

View All Publications
1 June 2004 in Gynecologic Oncology
Verified
Journal Article
Closed access
TCTak Hong Cheung
Tak Hong Cheung
KLK Lo
K Lo
SYS Yim
S Yim
LCL Chan
L Chan
MHM Heung
M Heung
YWY Wong
Y Wong

1 May 2001 in Cancer Letters
Verified
Journal Article
Closed access
TCTak Hong Cheung
Tak Hong Cheung
MYMay Mei Yung Yu
May Mei Yung Yu
KLKeith Wing Kit Lo
Keith Wing Kit Lo
SYSo Fan Yim
So Fan Yim
TCTony Kwok Hung Chung
Tony Kwok Hung Chung
YWYick Fu Wong
Yick Fu Wong

1 October 2001 in Cancer Letters
Verified
Journal Article
Closed access
TCTak Hong Cheung
Tak Hong Cheung
KLKeith Wing Kit Lo
Keith Wing Kit Lo
MYMay Mei Yung Yu
May Mei Yung Yu
SYSo Fan Yim
So Fan Yim
CPCho Sun Poon
Cho Sun Poon
YWYick Fu Wong
Yick Fu Wong

18 April 2012 in Arthritis Research & Therapy
Verified
Journal Article
Open access
SYShui Lian Yu
Shui Lian Yu
CCChan Chan
Chan Chan
CWChun-Kwok Wong
Chun-Kwok Wong
CSC.C. Szeto
C.C. Szeto
SHSuzanne Ho
Suzanne Ho
LTLai-Shan Tam
Lai-Shan Tam
Introduction: Prevalence of an abnormal Papanicolaou smear was significantly increased in lupus patients in cross-sectional studies, associated with a higher prevalence of high-risk human papillomavirus (HPV) infection. The nucleic acid-specific Toll-like receptors (TLRs) locate at the endolysosomal compartments and trigger the induction of cytokines for the innate immune response. This study evaluated whether abnormal host innate immune response in lupus patients may enhance HPV persistence. Methods: Protein levels of TLRs 3, 7, 8 and 9 in cervical epithelial cells of lupus patients and controls with or without HPV infection were assessed using flow cytometry. Characteristics associated with the differential expression of TLRs in systemic lupus erythematosus (SLE) were elucidated. The effect and interferon-stimulated genes (ISGs) (ISG15 and Mx-1) gene expressions were then measured in oncogenic HeLa (HPV18), CaSki (HPV) and C33A (HPV negative) cell lines using flow cytometry and quantitative real-time PCR. Ex vivo productions of cytokines and interferon-gamma (IFN-γ) upon TLR ligands stimulations were subsequently measured using cytometric bead array and ELISA. Results: For subjects with HPV infection, levels of TLR3 and TLR7 were significantly lower in lupus patients compared with controls. Significantly decreased TLRs 7, 8 and 9 levels were observed in HPV-negative SLE compared to healthy controls. For SLE with and without HPV infection, TLR7 and 9 levels were significantly lower in infected SLE than those in HPV-negative patients. Independent explanatory variables associated with down-regulation of TLR7 level included HPV infection and a higher cumulative dose of prednisolone; while a higher cumulative dose of hydroxychloroquine and HPV infection were associated with down-regulation of TLR9 level. In cervical cell lines, TLRs 3, 7, 8, 9 protein levels and antiviral ISG15 and Mx-1 gene expressions were inhibited in two oncogenic HPV types. Functional data showed that the induction of pro-inflammatory cytokines by TLR ligands (R837, ssRNA and ODN2395) was greatly impaired in CaSki and HeLa than C33A cells. Conclusions: In conclusion, prednisolone and TLR antagonist (hydroxychloroquine) may down-regulate protein levels of TLR7 and TLR9 in lupus patients, thereby decreasing the innate immune response against HPV infection. Upon infection, HPV further down-regulate TLR7 and 9 levels for viral persistence. Furthermore, reduction of nucleic acid-sensing TLRs 7, 8 and 9 in carcinogenic HPVs ensures that the expression of inducible pro-inflammatory cytokines is minimized to prevent the expression of antiviral ISGs (ISG15 and Mx-1) on a biologically relevant antiviral response.

1 February 2005 in Gynecologic Oncology
Verified
Journal Article
Closed access
TCTak Hong Cheung
Tak Hong Cheung
KLKeith Wing-Kit Lo
Keith Wing-Kit Lo
SYSo-Fan Yim
So-Fan Yim
CPCho-Sun Poon
Cho-Sun Poon
ACAlbert Yu-Kiu Cheung
Albert Yu-Kiu Cheung
YWYick-Fu Wong
Yick-Fu Wong

1 March 2004 in Gynecologic Oncology
Verified
Journal Article
Closed access
TCTak Hong Cheung
Tak Hong Cheung
WLW.K Lo
W.K Lo
MYM.Y Yu
M.Y Yu
WYWei Tse Yang
Wei Tse Yang
SHS Ho
S Ho