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Pu JJ, Lo AWI, Wong MCM, Choi WS, Ho G, Yang WF, Su YX. A quantitative comparison of bone resection margin distances in virtual surgical planning versus histopathology: a prospective study. Int J Surg 2024; 110:111-118. [PMID: 37737999 PMCID: PMC10793803 DOI: 10.1097/js9.0000000000000780] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 09/11/2023] [Indexed: 09/23/2023]
Abstract
BACKGROUND Positive bone margins have been shown to be associated with worse locoregional control and survival performance in oral oncology patients. With the application of computer-assisted surgery and patient-specific surgical guides, the authors can accurately execute the preoperative osteotomy plan. However, how well the authors can predict the margin distance in the final histopathology with a preoperative computed tomography (CT) scan, the factors associated with it, and how much leeway CT should spare when designing the osteotomy planes during virtual surgical planning (VSP) remain to be investigated. MATERIALS AND METHODS Patients from January 2021 to December 2022 with benign or malignant jaw tumors and with signs of bone marrow involvement in the preoperative CT scan in our center were prospectively recruited to the study. VSP and measurement of the closest margin distance in the CT scan were performed by the single team of surgeons. The resection specimen was processed, and the margin distances were measured by a dedicated senior pathologist with the knowledge of orientation of the osteotomy planes. RESULTS A total of 35 patients were recruited, with 21 malignant and 14 benign cases. Sixty-eight bone margins were quantitatively analyzed. No significant difference in margin distances measured from the CT scan and final histopathology was detected ( P =0.19), and there was a strong correlation between the two (r s =0.74, P <0.01). A considerable amount of variance was detected in the level of discrepancy between margin distances measured in the CT scan and final histopathology (overall SD=6.26 mm, malignancy SD=7.44 mm, benign SD=4.40 mm). No significant correlation existed between the two margin distances when only maxilla tumor margins were assessed ( P =0.16). CONCLUSION The bone margin distance in VSP is reliably correlated to the final pathological margin distance. A leeway distance of 15mm and 9mm should be considered when designing the osteotomy planes for malignancy and benign cases, respectively. Extra attention should be paid to maxilla cases when predetermining the osteotomy planes during VSP.
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Affiliation(s)
- Jane J. Pu
- Division of Oral and Maxillofacial Surgery
| | | | - May C. M. Wong
- Division of Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong
| | | | - Grace Ho
- Department of Radiology, Queen Mary Hospital, Hong Kong Special Administrative Region, People’s Republic of China
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Pang SL, Lo AWI, Wang R, Su YX. Sialendoscopic removal of metastatic adenocarcinoma in a mucous plug from Stensen's duct. Int J Oral Maxillofac Surg 2023; 52:1025-1027. [PMID: 36935282 DOI: 10.1016/j.ijom.2023.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 02/23/2023] [Accepted: 03/08/2023] [Indexed: 03/19/2023]
Abstract
Sialendoscopy is a minimally invasive technique used mainly in the diagnosis and treatment of obstructive salivary gland disorders. There has yet to be a report on its use in the diagnosis of metastatic disease. While metastatic cancer has been described in numerous head and neck anatomic subsites, it has not been reported to be found in a mucous plug in Stensen's duct. Sialendoscopy was performed in a 68-year-old female patient who presented with symptoms of ductal obstruction. Basket removal of a mucous plug was done and histopathological analysis of this specimen found adenocarcinoma. The overall clinical picture, imaging, and final histopathological results suggested that this patient had metastatic breast carcinoma to a mucous plug in Stensen's duct, the diagnosis of which was made with the aid of interventional sialendoscopy. This is the first report in which metastatic cancer was identified in a mucous plug in Stensen's duct. Sialendoscopy can be a useful tool to aid in the diagnosis of metastatic diseases in rare and unusual clinical situations.
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Affiliation(s)
- S L Pang
- Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong
| | - A W I Lo
- Division of Anatomical Pathology, Queen Mary Hospital, Hong Kong
| | - R Wang
- Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong
| | - Y-X Su
- Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong.
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Pu JJ, Choi WS, Yu P, Wong MCM, Lo AWI, Su YX. Do predetermined surgical margins compromise oncological safety in computer-assisted head and neck reconstruction? Oral Oncol 2020; 111:104914. [PMID: 32712577 DOI: 10.1016/j.oraloncology.2020.104914] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 07/12/2020] [Accepted: 07/13/2020] [Indexed: 12/13/2022]
Abstract
OBJECTIVES Computer assisted head and neck reconstruction has gained popularity over the past few years. In computer assisted surgery (CAS), surgical margins are predetermined in virtual surgery and resection guides are designed to be fitted intra-operatively. However, concerns have been raised regarding the oncological safety of predetermined surgical margins. Therefore, the aim of this study was to compare surgical margins, recurrence and survival outcomes in patients underwent CAS and non-CAS in head and neck reconstruction. METHODS We retrospectively reviewed the patients underwent oral and maxillofacial malignancies surgical excision and free flap reconstruction from October 2014 to December 2019 by the same chief surgeon. Patients were divided into two groups depending on whether CAS and predetermined surgical margins were adopted. The primary outcome was surgical resection margin and the secondary outcomes included recurrence and survival. RESULTS A total of 66 subjects were recruited with 37 in the CAS group and 29 in the non-CAS group. The follow-up rate was 100%. The average follow-up time was 24.5 months. No significant difference in resection margin was identified between the groups (p = 0.387). Tumor staging, margin status, perineural invasion, lymphovascular invasion and extranodal extension were identified as significant factors influencing survival. Both before and after adjustment for these prognostic factors identified, CAS and non-CAS group showed no significant difference in survival outcome. CONCLUSION Predetermined surgical margins do not compromise oncological safety in terms of resection margin, disease recurrence and patient survival.
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Affiliation(s)
- Jingya Jane Pu
- Division of Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Wing Shan Choi
- Division of Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Peirong Yu
- Department of Plastic Surgery, Division of Surgery, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - May Chun Mei Wong
- Division of Applied Oral Sciences & Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region
| | - Anthony W I Lo
- Anatomical Pathology Division, Queen Mary Hospital, Hong Kong Special Administrative Region
| | - Yu-Xiong Su
- Division of Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region.
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Li B, Lo AWI, Law S. ASO Author Reflections: Extracapsular Extension of Lymph Node: An Important Consideration for Gastric Cancer. Ann Surg Oncol 2020; 27:4233-4234. [PMID: 32382890 DOI: 10.1245/s10434-020-08546-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Indexed: 11/18/2022]
Affiliation(s)
- Bofei Li
- Division of Esophageal and Upper Gastrointestinal Surgery, Department of Surgery, Queen Mary Hospital, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
| | - Anthony W I Lo
- Division of Anatomical Pathology, Queen Mary Hospital, Pok Fu Lam, Hong Kong SAR, China
| | - Simon Law
- Division of Esophageal and Upper Gastrointestinal Surgery, Department of Surgery, Queen Mary Hospital, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China.
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Sridhar S, Cheng VCC, Wong SC, Yip CCY, Wu S, Lo AWI, Leung KH, Mak WWN, Cai J, Li X, Chan JFW, Lau SKP, Woo PCY, Lai WM, Kwan TH, Au TWK, Lo CM, Wong SCY, Yuen KY. Donor-Derived Genotype 4 Hepatitis E Virus Infection, Hong Kong, China, 2018. Emerg Infect Dis 2019; 25:425-433. [PMID: 30789146 PMCID: PMC6390757 DOI: 10.3201/eid2503.181563] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Hepatitis E virus (HEV) genotype 4 (HEV-4) is an emerging cause of acute hepatitis in China. Less is known about the clinical characteristics and natural history of HEV-4 than HEV genotype 3 infections in immunocompromised patients. We report transmission of HEV-4 from a deceased organ donor to 5 transplant recipients. The donor had been viremic but HEV IgM and IgG seronegative, and liver function test results were within reference ranges. After a mean of 52 days after transplantation, hepatitis developed in all 5 recipients; in the liver graft recipient, disease was severe and with progressive portal hypertension. Despite reduced immunosuppression, all HEV-4 infections progressed to persistent hepatitis. Four patients received ribavirin and showed evidence of response after 2 months. This study highlights the role of organ donation in HEV transmission, provides additional data on the natural history of HEV-4 infection, and points out differences between genotype 3 and 4 infections in immunocompromised patients.
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Wong GKC, Lam PK, Lo AWI, Chan AKY, Wang YX, Poon WS. Topically applied adipose-derived mesenchymal stem cell treatment in experimental focal cerebral ischaemia. Hong Kong Med J 2019; 25 Suppl 5:17. [PMID: 31416980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023] Open
Affiliation(s)
- G K C Wong
- Department of Surgery, The Chinese University of Hong Kong
- Chow Tai Fook-Cheng Yu Tung Surgical Stem Cell Research Center, The Chinese University of Hong Kong
| | - P K Lam
- Department of Surgery, The Chinese University of Hong Kong
- Chow Tai Fook-Cheng Yu Tung Surgical Stem Cell Research Center, The Chinese University of Hong Kong
| | - A W I Lo
- Department of Anatomical Pathology, Queen Mary Hospital
| | - A K Y Chan
- Department of Anatomical Pathology, Queen Mary Hospital
| | - Y X Wang
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong
| | - W S Poon
- Department of Surgery, The Chinese University of Hong Kong
- Chow Tai Fook-Cheng Yu Tung Surgical Stem Cell Research Center, The Chinese University of Hong Kong
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Jiang Y, Lo AWI, Wong A, Chen W, Wang Y, Lin L, Xu J. Prognostic significance of tumor-infiltrating immune cells and PD-L1 expression in esophageal squamous cell carcinoma. Oncotarget 2018; 8:30175-30189. [PMID: 28404915 PMCID: PMC5444735 DOI: 10.18632/oncotarget.15621] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 01/11/2017] [Indexed: 01/07/2023] Open
Abstract
Programmed death-1 receptor (PD-1) and its ligand (PD-L1) play an integral role in regulating the immune response against cancer. This study investigated the prognostic significance of PD-L1 expression on tumor cells and tumor-infiltrating immune cells (TILs) in the tumor microenvironment in Chinese patients with esophageal squamous cell carcinoma (ESCC). Archival formalin-fixed, paraffin-embedded ESCC samples from treatment-naïve patients with ESCC after surgery or by diagnostic endoscopic biopsy were collected between 2004 and 2014. Expression of PD-L1 in ESCC tumor specimens was assessed by immunohistochemistry (IHC), and the degree of TIL infiltration was evaluated by examining hematoxylin and eosin-stained (H&E) specimens. PD-L1+ as defined as ≥1% of tumor cell membranes showing ≥1+ intensity. In 428 patients, specimens from 341 (79.7%) were PD-L1+. In the definitive treatment group (patients who received curative esophagectomy or definitive [chemo-]radiation therapy), PD-L1 positivity was associated with a significantly shorter DFS and OS. In the palliative chemotherapy group exhibited, neither PFS nor OS correlated significantly with PD-L1 expression. PD-L1 expression was positively associated with TIL density. In 17 paired tumor tissues collected before and after treatment, an increase in PD-L1 expression was associated with disease progression, whereas a decrease in PD-L1 expression was associated with response to chemotherapy or disease control. So, PD-L1 expression was associated with a significantly worse prognosis in patients with ESCC. These observations suggest that PD-L1 may play a critical role in ESCC cancer progression and provide a rationale for developing PD-L1 inhibitors for treatment of a subset of ESCC patients.
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Affiliation(s)
- Yubo Jiang
- Department of Gastrointestinal Oncology, Affiliated Hospital Cancer Center, Academy of Military Medical Sciences, Beijing, P. R. China
| | - Anthony W I Lo
- Division of Anatomical Pathology, Department of Pathology & Clinical Biochemistry, Queen Mary Hospital, Hong Kong Special Administrative Region, P. R. China
| | - Angela Wong
- Global Early Development, Merck Serono China, Beijing, P. R. China
| | - Wenfeng Chen
- Global Early Development, Merck Serono China, Beijing, P. R. China
| | - Yan Wang
- Department of Gastrointestinal Oncology, Affiliated Hospital Cancer Center, Academy of Military Medical Sciences, Beijing, P. R. China
| | - Li Lin
- Department of Gastrointestinal Oncology, Affiliated Hospital Cancer Center, Academy of Military Medical Sciences, Beijing, P. R. China
| | - Jianming Xu
- Department of Gastrointestinal Oncology, Affiliated Hospital Cancer Center, Academy of Military Medical Sciences, Beijing, P. R. China
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Lam PK, Wang KKW, Lo AWI, Tong CSW, Ching DWC, Wong K, Yang Z, Kong T, Lo KKY, Choy RKW, Lai PBS, Wong GKC, Poon WS. Interactome and reciprocal activation of pathways in topical mesenchymal stem cells and the recipient cerebral cortex following traumatic brain injury. Sci Rep 2017; 7:5017. [PMID: 28694468 PMCID: PMC5504061 DOI: 10.1038/s41598-017-01772-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 03/31/2017] [Indexed: 11/12/2022] Open
Abstract
In this study, GFP-MSCs were topically applied to the surface of cerebral cortex within 1 hour of experimental TBI. No treatment was given to the control group. Three days after topical application, the MSCs homed to the injured parenchyma and improved the neurological function. Topical MSCs triggered earlier astrocytosis and reactive microglia. TBI penumbra and hippocampus had higher cellular proliferation. Apoptosis was suppressed at hippocampus at 1 week and reduced neuronal damaged was found in the penumbral at day 14 apoptosis. Proteolytic neuronal injury biomarkers (alphaII-spectrin breakdown products, SBDPs) and glial cell injury biomarker, glial fibrillary acidic protein (GFAP)-breakdown product (GBDPs) in injured cortex were also attenuated by MSCs. In the penumbra, six genes related to axongenesis (Erbb2); growth factors (Artn, Ptn); cytokine (IL3); cell cycle (Hdac4); and notch signaling (Hes1) were up-regulated three days after MSC transplant. Transcriptome analysis demonstrated that 7,943 genes were differentially expressed and 94 signaling pathways were activated in the topical MSCs transplanted onto the cortex of brain injured rats with TBI. In conclusion, topical application offers a direct and efficient delivery of MSCs to the brain.
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Affiliation(s)
- Ping K Lam
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong, SAR, China.,Chow Tai Fook-Cheng Yu Tung Surgical Stem Cell Research Center, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Kevin K W Wang
- Program for Neurotrauma, Neuroproteomics & Biomarkers Research, Departments of Psychiatry, McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Anthony W I Lo
- Department of Anatomical & Cellular Pathology, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Cindy S W Tong
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong, SAR, China.,Chow Tai Fook-Cheng Yu Tung Surgical Stem Cell Research Center, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Don W C Ching
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong, SAR, China.,Department of Anatomical & Cellular Pathology, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Kenneth Wong
- Department of Obstetrics and Gynecology, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Zhihui Yang
- Program for Neurotrauma, Neuroproteomics & Biomarkers Research, Departments of Psychiatry, McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Themis Kong
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong, SAR, China.,Chow Tai Fook-Cheng Yu Tung Surgical Stem Cell Research Center, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Kin K Y Lo
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong, SAR, China.,Chow Tai Fook-Cheng Yu Tung Surgical Stem Cell Research Center, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Richard K W Choy
- Department of Obstetrics and Gynecology, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Paul B S Lai
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong, SAR, China.,Chow Tai Fook-Cheng Yu Tung Surgical Stem Cell Research Center, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - George K C Wong
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong, SAR, China.,Chow Tai Fook-Cheng Yu Tung Surgical Stem Cell Research Center, The Chinese University of Hong Kong, Hong Kong, SAR, China
| | - Wai S Poon
- Department of Surgery, The Chinese University of Hong Kong, Hong Kong, SAR, China. .,Chow Tai Fook-Cheng Yu Tung Surgical Stem Cell Research Center, The Chinese University of Hong Kong, Hong Kong, SAR, China.
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Dai C, Geng R, Wang C, Wong A, Qing M, Hu J, Sun Y, Lo AWI, Li J. Concordance of immune checkpoints within tumor immune contexture and their prognostic significance in gastric cancer. Mol Oncol 2016; 10:1551-1558. [PMID: 27720576 DOI: 10.1016/j.molonc.2016.09.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 09/18/2016] [Accepted: 09/19/2016] [Indexed: 12/14/2022] Open
Abstract
Checkpoint blockade therapy has emerged as a novel approach for cancer immunotherapy in several malignancies. However, patient prognosis and disease progression relevant to immune checkpoints in gastric tumor microenvironment are not defined. This study aims to investigate the expression and prognostic significance of immune checkpoints within gastric cancer. In the study, a cohort of 398 cancer tissues from stage I to IV gastric cancer patients were assessed for programmed cell death 1 ligand 1 (PD-L1) expression and tumor-infiltrating lymphocyte (TIL) infiltration using immunohistochemistry to ascertain their survival correlation. The data revealed that higher TIL density correlated with less risk of disease progression, and exhibited survival benefits in gastric cancer patients, and PD-L1 positivity showed a significant association with the presence of high TIL infiltration. Furthermore, real-time quantitative polymerase chain reaction was performed to detect expression of multiple immune checkpoints with the relation to clinical outcome in 139 samples randomly selected from the same cohort, and higher messenger RNA levels of most immune checkpoints were associated with favorable outcome, while consistently showing a positive correlation with interferon gamma levels. In situ hybridization was used to determine the localization of Epstein-Barr virus (EBV) in 97 specimens, and showed EBV-positive gastric cancer samples correlated with PD-L1 expression and increased TIL density. These results suggest that induction of immune checkpoint within gastric cancer patients reflects a high immune infiltration density, especially in those with EBV-associated gastric cancer, which may direct patient selection for checkpoint blockade therapy.
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Affiliation(s)
- Congqi Dai
- Department of Oncology, Shanghai East Hospital, Tongji University, Shanghai, 200120, China
| | - Ruixuan Geng
- International Medical Services, Peking Union Medical College Hospital, Beijing, China
| | - Chenchen Wang
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
| | - Angela Wong
- Global Early Development, Merck Serono China, Beijing, China
| | - Min Qing
- Global Early Development, Merck Serono China, Beijing, China
| | - Jianjun Hu
- Global Early Development, Merck Serono China, Beijing, China
| | - Yu Sun
- Global Early Development, Merck Serono China, Beijing, China
| | - A W I Lo
- Division of Anatomical Pathology, Department of Pathology & Clinical Biochemistry, Queen Mary Hospital, Hong Kong Special Administrative Region
| | - Jin Li
- Department of Oncology, Shanghai East Hospital, Tongji University, Shanghai, 200120, China.
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Lee VHF, Lo AWI, Leung CY, Shek WH, Kwong DLW, Lam KO, Tong CC, Sze CK, Leung TW. Correlation of PD-L1 Expression of Tumor Cells with Survival Outcomes after Radical Intensity-Modulated Radiation Therapy for Non-Metastatic Nasopharyngeal Carcinoma. PLoS One 2016; 11:e0157969. [PMID: 27341634 PMCID: PMC4920427 DOI: 10.1371/journal.pone.0157969] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 06/08/2016] [Indexed: 12/24/2022] Open
Abstract
PURPOSE We investigated if programmed death-ligand 1 (PD-L1) expression levels were prognostic of survival outcomes after intensity-modulated radiation therapy (IMRT) for non-metastatic nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS 104 patients with non-metastatic NPC treated with radical IMRT were investigated for their PD-L1 expression by immunohistochemistry (IHC) which were correlated with survival endpoints including locoregional failure-free survival (LRFFS), progression-free survival (PFS), distant metastasis-free survival (DMFS) and overall survival (OS). RESULTS After a median follow-up of 7.6 years, 21 (20.2%), 19 (18.3%) and 31 (29.8%) patients suffered from locoregional failure, distant metastases and overall disease progression, respectively, and 31 (29.8%) patients died. Patients whose tumors had PD-L1 IHC 2+ (moderate to strong membrane staining in ≥ 25% of tumor cells) enjoyed longer LRFFS (5-year 100% vs. 74.4%, Hazard ratio [HR], 0.159, 95% confidence interval [CI], 0.021-0.988; P = 0.042) and marginally longer PFS (5-year 95.0% vs. 65.2%, HR, 0.351, 95% CI, 0.08-0.999, P = 0.067) compared to those whose tumors had PD-L1 IHC 0 (minimal membrane staining with PD-L1 in < 5% tumor cells or no staining with PD-L1) or 1+ (minimal to moderate membrane staining with PD-L1 in between 5-24% tumor cells). PD-L1 IHC 2+ was independently prognostic of both LRFFS (P = 0.014) and PFS (P = 0.045) in multivariable analyses. Only induction chemotherapy followed by concurrent chemoradiation was prognostic of DMFS (P = 0.003) and no prognostic factor for OS was identified. CONCLUSION PD-L1 expression levels correlated with LRRFS and PFS in non-metastatic NPC treated with radical IMRT. It may play a role in radiosensitivity for NPC, which should be further confirmed in prospective studies using immunotherapy together with IMRT.
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Affiliation(s)
- Victor H. F. Lee
- Department of Clinical Oncology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong
- * E-mail:
| | | | - Chun-Yin Leung
- Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong
| | - Wai-Hung Shek
- Anatomical Pathology, Queen Mary Hospital, Hong Kong, Hong Kong
| | - Dora L. W. Kwong
- Department of Clinical Oncology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong
| | - Ka-On Lam
- Department of Clinical Oncology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong
| | - Chi-Chung Tong
- Department of Clinical Oncology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong
| | - Chun-Kin Sze
- Department of Clinical Oncology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong
| | - To-Wai Leung
- Department of Clinical Oncology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong
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Chan DT, Luk AOY, So WY, Kong APS, Chow FCC, Ma RCW, Lo AWI. Natural history and outcome in Chinese patients with gastroenteropancreatic neuroendocrine tumours: - a 17-year retrospective analysis. BMC Endocr Disord 2016; 16:12. [PMID: 26911576 PMCID: PMC4766724 DOI: 10.1186/s12902-016-0087-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 01/20/2016] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND There is rising incidence of gastroenteropancreatic neuroendocrine tumours (GEP- NETs) in many parts of the world, but epidemiological data from Asian populations is rare. METHODS We conducted a retrospective study in a tertiary medical centre in Hong Kong, using updated diagnostic criteria. The presentation, clinical features, and disease outcome were reviewed for all patients with GEP-NETs confirmed histopathologically at the Prince of Wales Hospital, the Chinese University of Hong Kong, between 1996 and 2013, according to the latest 2010 World Health Organization Classification. RESULTS Among 126 patients, GEP- NETs were found in pancreas (34.9 %), rectum (33.3 %), and stomach (8.7 %), and most of them were non- functional GEP- NETs (91.3 %), mostly of grade 1 (G1) (87.3 %), and about 20 % had metastases on presentation. Age under 55 years, G1 tumours and absence of metastases were significant favourable predictors for survival in univariate analysis; whereas G2/3 tumours, size ≥2 cm, and metastases were significant predictors for disease progression (p < 0.05). In multivariate analysis, age and metastases on presentation were significant predictors of mortality (respective hazard ratios [HR] 1.05 [95 % confidence interval {CI} 1.02-1.08] and 6.52 [95 % CI 3.22-13.2]) and disease progression (respective HRs 1.05 [95 % CI 1.02-1.07] and 4.12 [95 % CI 1.96-8.68]), while higher tumour grade also independently predicted disease progression (HR 5.17 [95 % CI 2.05-13.05]) (all p < 0.05). CONCLUSION Non-functional tumours with non-specific symptoms account for the vast majority of GEP-NETs in this Chinese series. Multidisciplinary approach in the management of patients with GEP-NETs may help improve the treatment efficacy and outcome.
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Affiliation(s)
- Doris T Chan
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
| | - Andrea O Y Luk
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
| | - W Y So
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
| | - Alice P S Kong
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
| | - Francis C C Chow
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
| | - Ronald C W Ma
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
| | - Anthony W I Lo
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong.
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Abstract
An acquired ileal atresia is a rare occurrence. A 3-week-old neonate is presented, who developed postnatally a type 2 ileal atresia and an ileal stenosis within a pre-existing internal hernia secondary to an adhesion band. The literature reports a total of eight cases (4 females) with acquired ileal atresia in babies ranging in age from 3 weeks to 2 years (median 4 months). Mechanical forces (eg, adhesion band, intussusception and volvulus) onto the intestine are most frequently (75%) implicated as the primary event. The distal ileum is most often affected and a type 3A atresia is identified in six of eight (75%) cases.
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Affiliation(s)
- C H Houben
- Department of Surgery, Prince of Wales Hospital, Hong Kong, Hong Kong
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13
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Ho CYS, Ng AWH, Lee JFY, Lo AWI. Multiple submucosal neurogenic tumours in the large bowel. Histopathology 2013; 62:662-4. [PMID: 23379845 DOI: 10.1111/his.12049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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14
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Rüschoff J, Kerr KM, Grote HJ, Middel P, von Heydebreck A, Alves VA, Baldus SE, Büttner R, Carvalho L, Fink L, Jochum W, Lo AWI, López-Ríos F, Marx A, Molina TJ, Olszewski WT, Rieker RJ, Volante M, Thunnissen E, Wrba F, Celik I, Störkel S. Reproducibility of immunohistochemical scoring for epidermal growth factor receptor expression in non-small cell lung cancer: round robin test. Arch Pathol Lab Med 2012; 137:1255-61. [PMID: 23270410 DOI: 10.5858/arpa.2012-0605-oa] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
CONTEXT The addition of cetuximab to first-line chemotherapy substantially prolonged survival in patients with advanced non-small cell lung cancer whose tumors expressed high levels of epidermal growth factor receptor (EGFR; immunohistochemistry score of ≥200 on a scale of 0-300). OBJECTIVE To evaluate the interobserver reproducibility of this EGFR immunohistochemistry scoring system, based on both the tumor cell membrane staining intensity (graded 0-3+) and the percentage of cells staining at each intensity. DESIGN In parts 1 (initial feasibility study) and 2 of this 2-part round robin test, sections of different non-small cell lung cancer tissue microarrays were stained in a central reference laboratory. Following reference evaluation, EGFR expression in 30 selected tumor cores was characterized in serial sections by lung cancer pathology specialists. The reproducibility of scoring by different raters was assessed. Analysis of between-rater agreement was based on the allocation of EGFR immunohistochemistry scores into low- (<200) and high- (≥200) EGFR expression groups. RESULTS After discussion with raters of the issues impacting reproducibility identified in part 1 and following adjustment of processes, part 2 of the round robin test showed a high interobserver agreement in EGFR immunohistochemistry scoring, with an overall concordance rate of 90.9% and a mean κ coefficient of 0.812. Specimens with a reference EGFR immunohistochemistry score of lower than 200 and of 200 or higher showed mean concordance rates of 94.7% and 85.6%, respectively. CONCLUSIONS After appropriate training, assessing EGFR expression by this immunohistochemistry-based method allowed a highly reproducible allocation of non-small cell lung cancers into clinically relevant high- or low-EGFR expression groups.
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Affiliation(s)
- Josef Rüschoff
- Department of Pathology, Institute of Pathology Nordhessen, Kassel, Germany.
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15
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Li JCM, Lo AWI, Hon SSF, Ng SSM, Lee JFY, Leung KL. Institution learning curve of laparoscopic colectomy--a multi-dimensional analysis. Int J Colorectal Dis 2012; 27:527-33. [PMID: 22124675 DOI: 10.1007/s00384-011-1358-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/10/2011] [Indexed: 02/06/2023]
Abstract
BACKGROUND This study aimed to evaluate the learning curve for laparoscopic colorectal resection of a university colorectal unit, the operative outcome in its developing and established period of laparoscopic colorectal resection is compared. METHODS We analyzed 1,031 consecutive patients who underwent laparoscopic colorectal resections for colorectal carcinoma performed in a colorectal unit between April 1992 and December 2008. Multi-dimensional analyses of the learning curves of the institution and seven individual surgeons were performed. RESULTS The operative outcomes of period 2 (2002-2008) was generally better than period 1 (1992-2001), in terms of operative time, number of lymph nodes retrieved, intra-operative blood loss and transfusion. The conversion rate of period 1 was higher than period 2 (19.7% vs. 5.1%, p < 0.001). There were no difference in the rates of intra-operative complications (2% vs. 3.3%, p = 0.32) and major post-operative complications (6% vs. 4.5%, p = 0.28). Analysis of the operative time using moving average method showed that the operative time of period 2 was generally shorter than that of period 1. The operative time transiently increased when there were new trainee surgeons joining the program. The CUSUM analysis of institutional conversion rate showed a steady state being reached at 310 cases. For the rates of intra-operative and major post-operative complications, steady states were both achieved at around 50 cases, and these rates were maintained during the whole study period. CONCLUSIONS Operative outcome of laparoscopic colorectal resection improved with experience. Continuous training of new trainee would not affect the operative outcomes of an established specialized unit.
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Affiliation(s)
- Jimmy C M Li
- Department of Surgery, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China.
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16
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Chen J, Zhang B, Wong N, Lo AWI, To KF, Chan AWH, Ng MHL, Ho CYS, Cheng SH, Lai PBS, Yu J, Ng HK, Ling MT, Huang AL, Cai XF, Ko BCB. Sirtuin 1 is upregulated in a subset of hepatocellular carcinomas where it is essential for telomere maintenance and tumor cell growth. Cancer Res 2011; 71:4138-49. [PMID: 21527554 DOI: 10.1158/0008-5472.can-10-4274] [Citation(s) in RCA: 148] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hepatocellular carcinoma (HCC) is a highly malignant tumor with a poor prognosis. Treatment of HCC is complicated by the fact that the disease is often diagnosed at an advanced stage when it is no longer amenable to curative surgery, and current systemic chemotherapeutics are mostly inefficacious. Sirtuin 1 (SIRT1) is a class III histone deacetylase that is implicated in gene regulations and stress resistance. In this study, we found that SIRT1 is essential for the tumorigenesis of HCC. We showed that although SIRT1 was expressed at very low levels in normal livers, it was overexpressed in HCC cell lines and in a subset of HCC. Tissue microarray analysis of HCC and adjacent nontumoral liver tissues revealed a positive correlation between the expression levels of SIRT1 and advancement in tumor grades. Downregulation of SIRT1 consistently suppressed the proliferation of HCC cells via the induction of cellular senescence or apoptosis. SIRT1 silencing also caused telomere dysfunction-induced foci and nuclear abnormality that were clearly associated with reduced expressions of telomerase reverse transcriptase (TERT), and PTOP, which is a member of the shelter in complex. Ectopic expression of either TERT or PTOP in SIRT1-depleted cells significantly restored cell proliferation. There was also a positive correlation between the level of induction of SIRT1 and TERT [corrected] in human HCC. Finally, SIRT1-silencing sensitized HCC cells to doxorubicin treatment. Together, our findings reveal a novel function for SIRT1 in telomere maintenance of HCC, and they rationalize the clinical exploration of SIRT1 inhibitors for HCC therapy.
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Affiliation(s)
- Juan Chen
- The State Key Laboratory in Oncology in South China, Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong, China
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17
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Ho CYS, Tang NLS, Yeung AKY, Lau AKC, Hui J, Lo AWI. Abnormal expressions of the subunits of the UDP-N-acetylglucosamine: lysosomal enzyme, N-acetylglucosamine-1-phosphotransferase, result in the formation of cytoplasmic vacuoles resembling those of the I-cells. J Mol Med (Berl) 2006; 85:351-60. [PMID: 17160405 DOI: 10.1007/s00109-006-0128-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Revised: 09/06/2006] [Accepted: 10/04/2006] [Indexed: 10/23/2022]
Abstract
Defects in the multimeric enzyme, UDP-N-acetylglucosamine:lysosomal enzyme N-acetylglucosamine-1-phosphotransferase (GNPT), result in the diseases of mucolipidosis (ML). This enzyme generates the mannose 6-phosphate residues on newly synthesized lysosomal enzymes for the efficient receptor-mediated transport to lysosomes. The enzyme contains alpha/beta and gamma subunits. Mutations in the alpha/beta subunit result in the classical ML II and IIIA, while defects in the gamma subunit results in the clinically milder ML IIIC. I-cells, a distinct histological feature characterized by the presence of abnormal cytoplasmic vacuoles, are detected in many cell types, most noticeably, in ML II patients. In this study, we investigated the interactions of the alpha/beta and gamma subunits in the pathogenesis of I-cells. We noted low and deranged alpha/beta subunit expressions in human mucolipidosis cell lines. Unexpectedly, high gamma subunit expressions were also observed. In normal mouse fibroblasts, when alpha/beta subunit was suppressed, abnormal cytoplasmic vacuoles were induced, and up-regulation of the gamma subunit was also observed. On the other hand, suppressing the gamma subunit resulted in biphasic responses of the alpha/beta subunit, while abnormal cytoplasmic vacuoles were not formed, regardless of the expression levels of the alpha/beta subunit. Our data suggest reciprocal feedback mechanisms between alpha/beta and the gamma subunits. A fine balance of the expressions of these subunits may play an important role in the formation of I-cells in this group of lysosomal storage disorders.
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Affiliation(s)
- Cecilia Y S Ho
- Anatomical and Cellular Pathology, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR
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18
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Leung DTM, van Maren WWC, Chan FKL, Chan WS, Lo AWI, Ma CH, Tam FCH, To KF, Chan PKS, Sung JJY, Lim PL. Extremely low exposure of a community to severe acute respiratory syndrome coronavirus: false seropositivity due to use of bacterially derived antigens. J Virol 2006; 80:8920-8. [PMID: 16940504 PMCID: PMC1563915 DOI: 10.1128/jvi.00649-06] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Estimates of seropositivity to a new infectious agent in a community are useful to public health. For severe acute respiratory syndrome (SARS), the figures are conflicting. Herein, we screened 12,000 people in a community stricken by SARS 10 months previously and found 53 individuals (0.44%) who had immunoglobulin G antibodies to the SARS coronavirus (SARS-CoV) nucleocapsid (N) produced in bacteria. However, only seven of these (group 1) had sera which also reacted with the native N antigen expressed in SARS-CoV-infected Vero cells, N-transfected 293T cells, and tissues of infected SARS patients. Of these, six individuals had had SARS previously. The remaining person, as well as the 46 other individuals (group 2), were healthy and had no history of SARS. Group 1 antibodies recognized epitopes located slightly differently in N from those of group 2 antibodies, and a mouse hybridoma antibody resembling the former type was generated. Unusually, group 2 antibodies appeared to recognize cross-reactive bacterial epitopes that presumably were posttranslationally modified in eukaryotes and hence were probably not induced by SARS-CoV or related coronaviruses but rather by bacteria. The N antigen is thus highly unique. The extremely low rate (0.008%) of asymptomatic SARS infection found attests to the high virulence of the SARS-CoV virus.
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Affiliation(s)
- D T M Leung
- Clinical Immunology Unit, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
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19
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Abstract
AIMS p63 has been recently reported to be expressed in sarcomatoid/metaplastic carcinoma of the breast, in addition to its role as a myoepithelial marker. A large series of 34 metaplastic carcinomas, including cases with pure epithelial component (squamous cell and adenosquamous carcinomas), biphasic tumours with carcinomatous and sarcomatoid components and monophasic tumours with only spindle cell component, were evaluated for p63 expression with respect to the different cellular components. METHODS All of the metaplastic carcinomas were assessed for p63 and conventional epithelial and mesenchymal markers of AE1/3, CAM5.2 and vimentin by immunohistochemistry. RESULTS All of the different categories of metaplastic carcinomas showed similar clinico-pathological features (patient age, tumour size, nuclear grade, mitotic activity, lymph node status and hormonal receptor status). For metaplastic carcinoma with epithelial component only, p63 was only expressed in the squamous cell component, but not the adenocarcinoma component. Eight of the 10 tumours were positive for p63. For the tumours with sarcomatoid component, either singly or together with carcinomatous component, p63 was positive in 14 of 24 cases. Pure sarcomas and carcinomas were all negative for p63 staining by immunohistochemistry, thus rendering p63 staining highly specific for diagnosing metaplastic carcinoma. CONCLUSIONS Using p63 for diagnosis of metaplastic carcinoma gives a sensitivity of 65%, a specificity of 96%, a positive predictive value of 96%, and a negative predictive value of 66% and an accuracy of 78%. p63 may be used as an adjunct marker in the diagnosis of metaplastic carcinoma.
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Affiliation(s)
- Gary M Tse
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, Chinese University of Hong Kong.
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20
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Lee PW, Woo KS, Chow LTC, Ng HK, Chan WWM, Yu CM, Lo AWI. Images in cardiovascular medicine. Diffuse infiltration of lymphoma of the myocardium mimicking clinical hypertrophic cardiomyopathy. Circulation 2006; 113:e662-4. [PMID: 16567575 DOI: 10.1161/circulationaha.105.576306] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- P W Lee
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong SAR, China
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21
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Pedram M, Sprung CN, Gao Q, Lo AWI, Reynolds GE, Murnane JP. Telomere position effect and silencing of transgenes near telomeres in the mouse. Mol Cell Biol 2006; 26:1865-78. [PMID: 16479005 PMCID: PMC1430234 DOI: 10.1128/mcb.26.5.1865-1878.2006] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Reversible transcriptional silencing of genes located near telomeres, termed the telomere position effect (TPE), is well characterized in Saccharomyces cerevisiae. TPE has also been observed in human tumor cell lines, but its function remains unknown. To investigate TPE in normal mammalian cells, we developed clones of mouse embryonic stem (ES) cells that contain single-copy marker genes integrated adjacent to different telomeres. Analysis of these telomeric transgenes demonstrated that they were expressed at very low levels compared to the same transgenes integrated at interstitial sites. Similar to the situation in yeast, but in contrast to studies with human tumor cell lines, TPE in mouse ES cells was not reversed with trichostatin A. Prolonged culturing without selection resulted in extensive DNA methylation and complete silencing of telomeric transgenes, which could be reversed by treatment with 5-azacytidine. Thus, complete silencing of the telomeric transgenes appears to involve a two-step process in which the initial repression is reinforced by DNA methylation. Extensive methylation of the telomeric transgenes was also observed in various tissues and embryonic fibroblasts isolated from transgenic mice. In contrast, telomeric transgenes were not silenced in ES cell lines isolated from 3-day-old preimplantation embryos, consistent with the hypothesis that TPE plays a role in the development of the embryo.
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Affiliation(s)
- Mehrdad Pedram
- Department of Radiation Oncology, University of California, 1855 Folsom St., MCB 200, San Francisco, CA 94103, USA
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22
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Chow SCS, Ho CYS, Tam TTY, Wu C, Cheung T, Chan PKS, Ng MHL, Hui PK, Ng HK, Au DMY, Lo AWI. Specific epitopes of the structural and hypothetical proteins elicit variable humoral responses in SARS patients. J Clin Pathol 2006; 59:468-76. [PMID: 16461566 PMCID: PMC1860290 DOI: 10.1136/jcp.2005.029868] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Severe acute respiratory syndrome (SARS) is an infectious disease which was caused by a novel coronavirus (SARS-CoV). SARS has caused an outbreak in the world during 2003 and 2004, with 8098 individuals being infected and a death toll of 774 in 28 regions around the world. Specific humoral responses to viral infection remain unclear. OBJECTIVE To analyse the antigenicity of the SARS-CoV genome and identify potential antigenic epitopes in the structural proteins. METHODS Potential antigenic epitopes were identified in the structural proteins (nucleocapsid, membrane, spike, and small envelope proteins) and hypothetical proteins (SARS3a, 3b, 6, 7a, and 9b) that are specific for SARS-CoV. A peptide chip platform was created and the profiles of antibodies to these epitopes were investigated in 59 different SARS patients' sera obtained 6-103 days after the onset of the illness. Serial sera from five additional patients were also studied. RESULTS Epitopes at the N-terminus of the membrane protein and the C-terminus of nucleocapsid protein elicited strong antibody responses. Epitopes on the spike protein were only moderately immunogenic but the effects were persistent. Antibodies were also detected for some putative proteins, noticeably the C-termini of SARS3a and SARS6. CONCLUSIONS Important epitopes of the SARS-CoV genome that may serve as potential markers for the viral infection are identified. These specific antigenic sites may also be important for vaccine development against this new fatal infectious disease.
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Affiliation(s)
- S C S Chow
- Century Biotech Ltd, Hong Kong SAR, China
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23
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Chan WS, Wu C, Chow SCS, Cheung T, To KF, Leung WK, Chan PKS, Lee KC, Ng HK, Au DMY, Lo AWI. Coronaviral hypothetical and structural proteins were found in the intestinal surface enterocytes and pneumocytes of severe acute respiratory syndrome (SARS). Mod Pathol 2005; 18:1432-9. [PMID: 15920543 PMCID: PMC7100671 DOI: 10.1038/modpathol.3800439] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Severe acute respiratory syndrome (SARS) is a newly emerging infectious disease that haunted the world from November 2002 to July 2003. Little is known about the biology and pathophysiology of the novel coronavirus that causes SARS. The tissue and cellular distributions of coronaviral hypothetical and structural proteins in SARS were investigated. Antibodies against the hypothetical (SARS 3a, 3b, 6, 7a and 9b) and structural proteins (envelope, membrane, nucleocapsid and spike) of the coronavirus were generated from predicted antigenic epitopes of each protein. The presence of these proteins were first verified in coronavirus-infected Vero E6 tissue culture model. Immunohistochemical studies on different human tissues, including a cohort of nine autopsies, two liver biopsies and intestinal biopsies of SARS patients, further confirmed the existence of coronaviral hypothetical and structural proteins in the cytoplasm of pneumocytes and small intestinal surface enterocytes in SARS patients. With this vast array of antibodies, no signal was observed in other cell types including those organs in which reverse transcriptase-polymerase chain reactions were reported to be positive. Structural proteins and the functionally undefined hypothetical proteins were expressed in coronavirus-infected cells with distinct expression pattern in different organs in SARS patients. These antipeptide antibodies can be useful for the diagnosis of SARS at the tissue level.
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Affiliation(s)
- Wai S Chan
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong SAR, China
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24
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Tse GMK, Wong FC, Tsang AKH, Lee CS, Lui PCW, Lo AWI, Law BKB, Scolyer RA, Karim RZ, Putti TC. Stromal nitric oxide synthase (NOS) expression correlates with the grade of mammary phyllodes tumour. J Clin Pathol 2005; 58:600-4. [PMID: 15917410 PMCID: PMC1770683 DOI: 10.1136/jcp.2004.023028] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Nitric oxide synthase (NOS), particularly endothelial and inducible forms (e/i-NOS), are expressed in various cancers, including breast cancer. In mammary fibroepithelial lesions, NOS expression in stromal cells has been reported to be lower in fibroadenomas than in phyllodes tumours. AIMS To investigate NOS expression in phyllodes tumours of varying degrees of malignancy. METHODS One hundred and sixty seven mammary phyllodes tumours (97 benign, 47 borderline malignant, and 23 frankly malignant) were evaluated for e-NOS and i-NOS expression by immunohistochemistry. Correlations with previously reported expression of stromal vascular growth factor (VEGF) and microvessel density were also performed. RESULTS Stromal expression of e-NOS was absent, weak, moderate, and strong in 43%, 31%, 13%, and 13% of benign tumours; 17%, 26%, 13%, and 44% of borderline malignant tumours; and 17%, 35%, 13%, and 35% of frankly malignant tumours, respectively. Stromal expression of i-NOS was 77%, 18%, 4%, and 1% in benign tumours; 42%, 28%, 19%, and 11% in borderline malignant tumours; and 43%, 13%, 26%, and 18% in frankly malignant tumours, respectively. Stromal expression of both i-NOS and e-NOS was significantly different between the benign and malignant (borderline and frank) groups of phyllodes tumours (p < 0.0001). Furthermore, the expression of i-NOS correlated with stromal VEGF expression and microvessel density. The expression of NOS in the epithelial cells was strong, and showed no differences between the different groups of tumours. CONCLUSIONS Higher stromal expression of NOS in phyllodes tumours is associated with malignancy, suggesting a possible role in malignant progression, particularly metastasising potential.
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Affiliation(s)
- G M K Tse
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, Chinese University of Hong Kong, Ngan Shing Street, Shatin, NT, Hong Kong, China.
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25
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Law PTW, Wong CH, Au TCC, Chuck CP, Kong SK, Chan PKS, To KF, Lo AWI, Chan JYW, Suen YK, Chan HYE, Fung KP, Waye MMY, Sung JJY, Lo YMD, Tsui SKW. The 3a protein of severe acute respiratory syndrome-associated coronavirus induces apoptosis in Vero E6 cells. J Gen Virol 2005; 86:1921-1930. [PMID: 15958670 DOI: 10.1099/vir.0.80813-0] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
An outbreak of severe acute respiratory syndrome (SARS) occurred in China and the first case emerged in mid-November 2002. The aetiological agent of this disease was found to be a previously unknown coronavirus, SARS-associated coronavirus (SARS-CoV). The detailed pathology of SARS-CoV infection and the host response to the viral infection are still not known. The 3a gene encodes a non-structural viral protein, which is predicted to be a transmembrane protein. In this study, it was shown that the 3a protein was expressed in the lungs and intestinal tissues of SARS patients and that the protein localized to the endoplasmic reticulum in 3a-transfected monkey kidney Vero E6 cells. In vitro experiments of chromatin condensation and DNA fragmentation suggested that the 3a protein may trigger apoptosis. These data showed that overexpression of a single SARS-CoV protein can induce apoptosis in vitro.
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Affiliation(s)
- Patrick T W Law
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
- Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Chi-Hang Wong
- Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Thomas C C Au
- Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Chi-Pang Chuck
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Siu-Kai Kong
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Paul K S Chan
- Department of Microbiology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Ka-Fai To
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Anthony W I Lo
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Judy Y W Chan
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Yick-Keung Suen
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - H Y Edwin Chan
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Kwok-Pui Fung
- The Croucher Laboratory for Human Genomics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Mary M Y Waye
- The Croucher Laboratory for Human Genomics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Joseph J Y Sung
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
- Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Y M Dennis Lo
- Department of Chemical Pathology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
- Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Stephen K W Tsui
- The Croucher Laboratory for Human Genomics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
- Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
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26
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Law PTW, Wong CH, Au TCC, Chuck CP, Kong SK, Chan PKS, To KF, Lo AWI, Chan JYW, Suen YK, Chan HYE, Fung KP, Waye MMY, Sung JJY, Lo YMD, Tsui SKW. The 3a protein of severe acute respiratory syndrome-associated coronavirus induces apoptosis in Vero E6 cells. J Gen Virol 2005. [PMID: 15958670 DOI: 10.1099/vir.0.80813‐0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
An outbreak of severe acute respiratory syndrome (SARS) occurred in China and the first case emerged in mid-November 2002. The aetiological agent of this disease was found to be a previously unknown coronavirus, SARS-associated coronavirus (SARS-CoV). The detailed pathology of SARS-CoV infection and the host response to the viral infection are still not known. The 3a gene encodes a non-structural viral protein, which is predicted to be a transmembrane protein. In this study, it was shown that the 3a protein was expressed in the lungs and intestinal tissues of SARS patients and that the protein localized to the endoplasmic reticulum in 3a-transfected monkey kidney Vero E6 cells. In vitro experiments of chromatin condensation and DNA fragmentation suggested that the 3a protein may trigger apoptosis. These data showed that overexpression of a single SARS-CoV protein can induce apoptosis in vitro.
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Affiliation(s)
- Patrick T W Law
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China.,Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Chi-Hang Wong
- Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Thomas C C Au
- Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Chi-Pang Chuck
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Siu-Kai Kong
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Paul K S Chan
- Department of Microbiology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Ka-Fai To
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Anthony W I Lo
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Judy Y W Chan
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Yick-Keung Suen
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - H Y Edwin Chan
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Kwok-Pui Fung
- The Croucher Laboratory for Human Genomics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China.,Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Mary M Y Waye
- The Croucher Laboratory for Human Genomics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China.,Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Joseph J Y Sung
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China.,Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Y M Dennis Lo
- Department of Chemical Pathology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China.,Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
| | - Stephen K W Tsui
- The Croucher Laboratory for Human Genomics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China.,Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China.,Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Shatin, NT, Hong Kong SAR, China
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Chan PKS, To KF, Lo AWI, Cheung JLK, Chu I, Au FWL, Tong JHM, Tam JS, Sung JJY, Ng HK. Persistent infection of SARS coronavirus in colonic cells in vitro. J Med Virol 2005; 74:1-7. [PMID: 15258961 PMCID: PMC7166317 DOI: 10.1002/jmv.20138] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Severe acute respiratory syndrome coronavirus (SARS‐CoV) can produce gastrointestinal symptoms. The intestinal tract is the only extrapulmonary site where viable viruses have been detected. This study examined seven established human intestinal cell lines, DLD‐1, HCT‐116, HT‐29, LoVo, LS‐180, SW‐480 and SW‐620, for their permissiveness to SARS‐CoV infection. The results showed that only LoVo cells were permissive to SARS‐CoV infection as evident by positive findings from indirect immunofluorescence staining for intracellular viral antigens, in situ hybridization for intracellular viral RNA, and electron microscopy for intracellular viral particles. In contrast to Vero cells, SARS‐CoV did not produce cytopathic effects on LoVo cells. However, LoVo cells were found to be highly permissive for productive infection with a high viral titre (>3 × 107 viral copies/ml) produced in culture supernatant following a few days of incubation. SARS‐CoV established a stable persistent chronic infection that could be maintained after multiple passages. Being a cell line of human origin, LoVo cells could be a useful in vitro model for studying the biology and persistent infection of SARS‐CoV. Our results on the expression of angiotensin‐converting enzyme 2 (ACE2), a recently identified cellular receptor for SARS‐CoV, in these cell lines indicated that it might not be the sole determinant for cells to be susceptible to SARS‐CoV infection. J. Med. Virol. 74:1–7, 2004. © 2004 Wiley‐Liss, Inc.
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Affiliation(s)
- Paul K S Chan
- Centre for Emerging Infectious Diseases, and Department of Microbiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong SAR, China.
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Chow C, Liu AY, Chan WS, Lei KIK, Chan WY, Lo AWI. AKT plays a role in the survival of the tumor cells of extranodal NK/T-cell lymphoma, nasal type. Haematologica 2005; 90:274-5. [PMID: 15710591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023] Open
Abstract
Phosphorylated AKT has been detected in extranodal NK/T-cell lymphoma, nasal type (ENTL). Either interleukin-2 (IL-2) or interleukin-15 (IL-15) could prevent AKT dephosphorylation and apoptosis in the NK-92 cell line model. IL-15, but not IL-2, was preferentially elevated in patients' serum. AKT and IL-15 may be important in ENTL tumor survival.
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To KF, Chan MWY, Leung WK, Ng EKW, Yu J, Bai AHC, Lo AWI, Chu SH, Tong JHM, Lo KW, Sung JJY, Chan FKL. Constitutional activation of IL-6-mediated JAK/STAT pathway through hypermethylation of SOCS-1 in human gastric cancer cell line. Br J Cancer 2004; 91:1335-41. [PMID: 15354212 PMCID: PMC2409891 DOI: 10.1038/sj.bjc.6602133] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The interleukin-mediated Janus kinase (JAK)/STAT pathway plays a crucial role in carcinogenesis. Recently, increased STAT3 activity was found in hepatocellular carcinoma and multiple myeloma in which there was silencing of SOCS-1 (suppressor of cytokine signalling-1) by gene promoter hypermethylation. We investigated the expression level of interleukin-6 (IL-6) and SOCS-1 in gastric cancer cell lines. Expression of SOCS-1 correlated with IL-6 level in most of the cell lines, except for AGS cells in which SOCS-1 was absent despite a high level of IL-6 production. Methylation analysis by methylation-specific polymerase chain reaction and bisulphite sequencing revealed that CpG island of SOCS-1 was densely methylated in AGS cells. Demethylation treatment by 5'aza-deoxycytidine restored SOCS-1 expression and also suppressed constitutive STAT3 phosphorylation in AGS cells. Moreover, methylation of SOCS-1 was detected in 27.5% (11 of 40) of primary gastric tumours samples, 10% (one of 10) of adjacent noncancer tissues but not in any (zero of nine) normal gastric mucosa. Methylation of SOCS-1 also correlated with the loss of mRNA expression in some primary gastric cancers. In conclusion, this is the first report to demonstrate that hypermethylation of SOCS-1 led to gene silencing in gastric cancer cell line and primary tumour samples. Downregulation of SOCS-1 cooperates with IL-6 in the activation of JAK/STAT pathway in gastric cancer.
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Affiliation(s)
- K F To
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, NT, Hong Kong.
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To KF, Lo AWI. Exploring the pathogenesis of severe acute respiratory syndrome (SARS): the tissue distribution of the coronavirus (SARS-CoV) and its putative receptor, angiotensin-converting enzyme 2 (ACE2). J Pathol 2004; 203:740-3. [PMID: 15221932 PMCID: PMC7167902 DOI: 10.1002/path.1597] [Citation(s) in RCA: 159] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Severe acute respiratory syndrome (SARS) is an emerging infectious disease associated with a new coronavirus, SARS-CoV. Pulmonary involvement is the dominant clinical feature but extra-pulmonary manifestations are also common. Factors that account for the wide spectrum of organ system involvement and disease severity are poorly understood and the pathogenesis of SARS-CoV infection remains unclear. Angiotensin converting enzyme 2 (ACE2) has recently been identified as the functional cellular receptor for SARS-CoV. Studies of the tissue and cellular distribution of SARS-CoV, and ACE2 protein expression, reveal new insights into the pathogenesis of this deadly disease. ACE2 is expressed at high level in the primary target cells of SARS-CoV, namely pneumocytes and surface enterocytes of the small intestine. Despite the fact that SARS-CoV can infect the lung and intestine, the tissue responses in these two organs are different. All other tissues and cell types expressing ACE2 may be potential targets of SARS-CoV infection. Remarkably, endothelial cells, which express ACE2 to a high level, have not been shown to be infected by SARS-CoV. There is also evidence that cell types without detectable ACE2 expression may also be infected by the virus. Furthermore, studies in a new human cell culture model have indicated that the presence of ACE2 alone is not sufficient for maintaining viral infection. Therefore, other virus receptors or co-receptors may be required in different tissues. Moreover, the interaction between SARS-CoV and the immunological or lymphoid system remains to be defined. It is clear that we are only at the dawn of our understanding of the pathogenesis of SARS. As our knowledge of the pathogenic mechanisms improves, a more rational approach to therapeutic and vaccine development can be designed in order to combat this new and fatal human disease.
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Affiliation(s)
- K F To
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong SAR, China.
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Abstract
Mammary phyllodes tumors are uncommon stromal neoplasms, and are divided into benign, borderline and malignant groups basing on histologic criteria. While benign phyllodes tumors may recur, borderline phyllodes tumors show higher propensity to recur locally and rarely metastasize, and malignant phyllodes tumors show even higher chances of local recurrences or distant metastases. c-kit is a proto-oncogene that encodes a tyrosine kinase receptor (CD117) and is a marker for gastrointestinal stromal tumors (GIST). With the advent of therapeutic agent targeted at this receptor for GIST, we investigated 179 phyllodes tumors (101 benign, 50 borderline, 28 malignant) for c-kit expression using immunohistochemistry. The staining was compared to the degree of malignancy, and to the degree of stromal cellularity, mitotic activity, nuclear pleomorphism and stromal overgrowth. The overall positive rate for c-kit was 29% (52/179) and 17% (17/101), 24% (12/50) and 46% (13/28), respectively, for benign, borderline malignant and frank malignant phyllodes and the differences between all categories were significant (chi2=13.844, P=0.001). In mammary phyllodes tumors, there was increasing c-kit expression with increasing degree of malignancy, up to 46% in malignant cases. This provides strong evidence that c-kit receptor mediated tyrosine kinase involvement in the pathogenesis of phyllodes tumors, and the therapeutic agent, STI571, Glivec, may be a potentially useful drug for its management.
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Affiliation(s)
- Gary M K Tse
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong.
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Tse GMK, To KF, Chan PKS, Lo AWI, Ng KC, Wu A, Lee N, Wong HC, Mak SM, Chan KF, Hui DSC, Sung JJY, Ng HK. Pulmonary pathological features in coronavirus associated severe acute respiratory syndrome (SARS). J Clin Pathol 2004; 57:260-5. [PMID: 14990596 PMCID: PMC1770245 DOI: 10.1136/jcp.2003.013276] [Citation(s) in RCA: 178] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Severe acute respiratory syndrome (SARS) became a worldwide outbreak with a mortality of 9.2%. This new human emergent infectious disease is dominated by severe lower respiratory illness and is aetiologically linked to a new coronavirus (SARS-CoV). METHODS Pulmonary pathology and clinical correlates were investigated in seven patients who died of SARS in whom there was a strong epidemiological link. Investigations include a review of clinical features, morphological assessment, histochemical and immunohistochemical stainings, ultrastructural study, and virological investigations in postmortem tissue. RESULTS Positive viral culture for coronavirus was detected in most premortem nasopharyngeal aspirate specimens (five of six) and postmortem lung tissues (two of seven). Viral particles, consistent with coronavirus, could be detected in lung pneumocytes in most of the patients. These features suggested that pneumocytes are probably the primary target of infection. The pathological features were dominated by diffuse alveolar damage, with the presence of multinucleated pneumocytes. Fibrogranulation tissue proliferation in small airways and airspaces (bronchiolitis obliterans organising pneumonia-like lesions) in subpleural locations was also seen in some patients. CONCLUSIONS Viable SARS-CoV could be isolated from postmortem tissues. Postmortem examination allows tissue to be sampled for virological investigations and ultrastructural examination, and when coupled with the appropriate lung morphological changes, is valuable to confirm the diagnosis of SARS-CoV, particularly in clinically unapparent or suspicious but unconfirmed cases.
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Affiliation(s)
- G M-K Tse
- Department of Anatomical and Cellular Pathology, Chinese University of Hong Kong, Prince of Wales Hospital, Ngan Shing Street, Shatin, NT, Hong Kong SAR, China
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Abstract
BACKGROUND Severe acute respiratory syndrome (SARS) is a newly described form of atypical pneumonia linked to a novel coronavirus. AIMS To review the sputum cytology of 15 patients who fulfilled the World Health Organisation clinical criteria for SARS in an attempt to evaluate whether early diagnosis is feasible with routine sputum examination. METHODS All sputum samples from patients with SARS from the four major hospitals in Hong Kong were reviewed; abnormalities were sought in the cellular component, including abnormal numbers and morphology of the component cells compared with those from age matched controls taken over the same period one year ago. RESULTS Fifteen sputum samples from patients were compared with 25 control samples. In the patients with SARS, loose aggregates of macrophages were seen more frequently in the sputum. These macrophages frequently showed morphological changes, such as cytoplasmic foaminess, vacuole formation, and nuclear changes (including multinucleation and a ground glass appearance) when compared with the control samples. CONCLUSIONS The cytological features of SARS are non-specific, but the observation of any of the described features should prompt further investigations, especially in patients with suspicious clinical features.
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Affiliation(s)
- G M K Tse
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, Chinese University of Hong Kong, Ngan Shing Street, NT, Hong Kong ROC.
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To KF, Tong JHM, Chan PKS, Au FWL, Chim SSC, Chan KCA, Cheung JLK, Liu EYM, Tse GMK, Lo AWI, Lo YMD, Ng HK. Tissue and cellular tropism of the coronavirus associated with severe acute respiratory syndrome: an in-situ hybridization study of fatal cases. J Pathol 2004; 202:157-63. [PMID: 14743497 PMCID: PMC7167900 DOI: 10.1002/path.1510] [Citation(s) in RCA: 152] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Severe acute respiratory syndrome (SARS) is a new human infectious disease with significant morbidity and mortality. The disease has been shown to be associated with a new coronavirus (SARS‐CoV). The clinical and epidemiological aspects of SARS have been described. Moreover, the viral genome of SARS‐CoV has been fully sequenced. However, much of the biological behaviour of the virus is not known and data on the tissue and cellular tropism of SARS‐CoV are limited. In this study, six fatal cases of SARS were investigated for the tissue and cellular tropism of SARS‐CoV using an in‐situ hybridization (ISH) technique. Among all the tissues studied, positive signals were seen in pneumocytes in the lungs and surface enterocytes in the small bowel. Infected pneumocytes were further confirmed by immunofluorescence–fluorescence in‐situ hybridization (FISH) analysis. These results provide important information concerning the tissue tropism of SARS‐CoV, which is distinct from previously identified human coronaviruses, and suggest the possible involvement of novel receptors in this infection. Whereas the lung pathology was dominated by diffuse alveolar damage, the gut was relatively intact. These findings indicated that tissue responses to SARS‐CoV infection are distinct in different organs. Copyright © 2004 John Wiley & Sons, Ltd.
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Affiliation(s)
- K F To
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong SAR, China.
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Abstract
A 56 year old man with previously unsuspected recurrence of squamous cell carcinoma of the oesophagus presented with dyspnoea. Bronchoscopy and computed tomography suggested bronchopneumonic changes with an infectious cause. He suffered a rapidly deteriorating course and died despite active treatment, including antibiotics and mechanical ventilation. Necropsy revealed a florid pulmonary tumour microembolism mimicking alveolitis. No bronchopneumonia was seen. The emboli arose from loosely attached tumour vegetations in the tricuspid valve. In a patient with known malignancy, tumour microembolism should be considered as an uncommon cause of rapid respiratory failure, refractory to antibiotic treatment.
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Affiliation(s)
- A W I Lo
- Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, NT, Hong Kong SAR, China
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Abstract
We show that Trichostatin A (TSA)-induced partial histone hyperacetylation causes a unidirectional shift in the position of a previously defined binding domain for the centromere-specific histone H3 homologue CENP-A at a human neocentromere. The shift of approximately 320 kb is fully reversible when TSA is removed, but is accompanied by an apparent reduction in the density of CENP-A per unit length of genomic DNA at the neocentromere. TSA treatment also instigates a reversible abolition of a previously defined major domain of differentially delayed replication timing that was originally established at the neocentromeric site. None of these changes has any measurable deleterious effects on mitosis or neocentromere function. The data suggest pliability of centromeric chromatin in response to epigenetic triggers, and the non-essential nature of the regions of delayed replication for centromere function. Reversibility of the CENP-A-binding position and the predominant region of delayed replication timing following removal of TSA suggest strong memory at the original site of neocentromeric chromatin formation.
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Affiliation(s)
- Jeffrey M Craig
- Murdoch Childrens Research Institute, Royal Children's Hospital, Flemington Road, Melbourne, Victoria 3052, Australia
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Lo AWI, Sabatier L, Fouladi B, Pottier G, Ricoul M, Murnane JP. DNA amplification by breakage/fusion/bridge cycles initiated by spontaneous telomere loss in a human cancer cell line. Neoplasia 2002; 4:531-8. [PMID: 12407447 PMCID: PMC1503667 DOI: 10.1038/sj.neo.7900267] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2002] [Accepted: 07/24/2002] [Indexed: 11/09/2022]
Abstract
The development of genomic instability is an important step in generating the multiple genetic changes required for cancer. One consequence of genomic instability is the overexpression of oncogenes due to gene amplification. One mechanism for gene amplification is the breakage/fusion/bridge (B/F/B) cycle that involves the repeated fusion and breakage of chromosomes following the loss of a telomere. B/F/B cycles have been associated with low-copy gene amplification in human cancer cells, and have been proposed to be an initiating event in high-copy gene amplification. We have found that spontaneous telomere loss on a marker chromosome 16 in a human tumor cell line results in sister chromatid fusion and prolonged periods of chromosome instability. The high rate of anaphase bridges involving chromosome 16 demonstrates that this instability results from B/F/B cycles. The amplification of subtelomeric DNA on the marker chromosome provides conclusive evidence that B/F/B cycles initiated by spontaneous telomere loss are a mechanism for gene amplification in human cancer cells.
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Affiliation(s)
- Anthony W I Lo
- Radiation Oncology Research Laboratory, University of California, 1855 Folsom Street, MCB 200, San Francisco, CA 94103, USA
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Lo AWI, Sprung CN, Fouladi B, Pedram M, Sabatier L, Ricoul M, Reynolds GE, Murnane JP. Chromosome instability as a result of double-strand breaks near telomeres in mouse embryonic stem cells. Mol Cell Biol 2002; 22:4836-50. [PMID: 12052890 PMCID: PMC133890 DOI: 10.1128/mcb.22.13.4836-4850.2002] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Telomeres are essential for protecting the ends of chromosomes and preventing chromosome fusion. Telomere loss has been proposed to play an important role in the chromosomal rearrangements associated with tumorigenesis. To determine the relationship between telomere loss and chromosome instability in mammalian cells, we investigated the events resulting from the introduction of a double-strand break near a telomere with I-SceI endonuclease in mouse embryonic stem cells. The inactivation of a selectable marker gene adjacent to a telomere as a result of the I-SceI-induced double-strand break involved either the addition of a telomere at the site of the break or the formation of inverted repeats and large tandem duplications on the end of the chromosome. Nucleotide sequence analysis demonstrated large deletions and little or no complementarity at the recombination sites involved in the formation of the inverted repeats. The formation of inverted repeats was followed by a period of chromosome instability, characterized by amplification of the subtelomeric region, translocation of chromosomal fragments onto the end of the chromosome, and the formation of dicentric chromosomes. Despite this heterogeneity, the rearranged chromosomes eventually acquired telomeres and were stable in most of the cells in the population at the time of analysis. Our observations are consistent with a model in which broken chromosomes that do not regain a telomere undergo sister chromatid fusion involving nonhomologous end joining. Sister chromatid fusion is followed by chromosome instability resulting from breakage-fusion-bridge cycles involving the sister chromatids and rearrangements with other chromosomes. This process results in highly rearranged chromosomes that eventually become stable through the addition of a telomere onto the broken end. We have observed similar events after spontaneous telomere loss in a human tumor cell line, suggesting that chromosome instability resulting from telomere loss plays a role in chromosomal rearrangements associated with tumor cell progression.
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Affiliation(s)
- Anthony W. I. Lo
- Radiation Oncology Research Laboratory, University of California, San Francisco, California 94103, Laboratoire de Radiobiologie et Oncologie, Commissariat à l'Energie Atomique, Fontenay-aux-Roses, France
| | - Carl N. Sprung
- Radiation Oncology Research Laboratory, University of California, San Francisco, California 94103, Laboratoire de Radiobiologie et Oncologie, Commissariat à l'Energie Atomique, Fontenay-aux-Roses, France
| | - Bijan Fouladi
- Radiation Oncology Research Laboratory, University of California, San Francisco, California 94103, Laboratoire de Radiobiologie et Oncologie, Commissariat à l'Energie Atomique, Fontenay-aux-Roses, France
| | - Mehrdad Pedram
- Radiation Oncology Research Laboratory, University of California, San Francisco, California 94103, Laboratoire de Radiobiologie et Oncologie, Commissariat à l'Energie Atomique, Fontenay-aux-Roses, France
| | - Laure Sabatier
- Radiation Oncology Research Laboratory, University of California, San Francisco, California 94103, Laboratoire de Radiobiologie et Oncologie, Commissariat à l'Energie Atomique, Fontenay-aux-Roses, France
| | - Michelle Ricoul
- Radiation Oncology Research Laboratory, University of California, San Francisco, California 94103, Laboratoire de Radiobiologie et Oncologie, Commissariat à l'Energie Atomique, Fontenay-aux-Roses, France
| | - Gloria E. Reynolds
- Radiation Oncology Research Laboratory, University of California, San Francisco, California 94103, Laboratoire de Radiobiologie et Oncologie, Commissariat à l'Energie Atomique, Fontenay-aux-Roses, France
| | - John P. Murnane
- Radiation Oncology Research Laboratory, University of California, San Francisco, California 94103, Laboratoire de Radiobiologie et Oncologie, Commissariat à l'Energie Atomique, Fontenay-aux-Roses, France
- Corresponding author. Mailing address: Department of Radiation Oncology, University of California, 1855 Folsom St., MCB 200, San Francisco, CA 94103. Phone: (415) 476-9083. Fax: (415) 476-9069. E-mail:
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