Douglas Webber
University of British Columbia
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Publication
Featured researches published by Douglas Webber.
The American Journal of Surgical Pathology | 2010
Fang-I Lu; De Wet van Niekerk; David A. Owen; Susan Tha; Dmitry A. Turbin; Douglas Webber
Sessile serrated adenomas (SSAs) are associated with colorectal carcinomas (CRCs) that demonstrate high microsatellite instability (MSI-H). Currently, SSAs are managed clinically in a similar fashion to adenomatous polyps (APs). We studied the natural history of SSA by analyzing the outcome of previously undiagnosed SSAs and comparing it with that of hyperplastic polyps (HPs) and APs. All colorectal polyps diagnosed between 1980 and 2001 as HP were selected for study. Polyps identified as possible SSAs were reviewed by 3 pathologists, and the diagnosis was confirmed. Clinical follow-up was obtained for each SSA patient and matched with control HP and AP patients. In total, 1402 colorectal polyps diagnosed as HP were examined and 81 polyps in 55 patients (5.8%) were rediagnosed as SSA. Of these, 40 SSA patients had no previous history of either CRC or AP with high-grade dysplasia (HGD). Of these 40 patients, 5 developed subsequent CRCs and 1 developed AP with HGD. The incidence of subsequent CRCs was significantly higher in SSA patients than in control patients with HP (12.5% vs. 1.8%) and AP (12.5% vs. 1.8%). All of the subsequent CRCs or APs with HGD developed in the proximal colon. Four of the 5 CRCs demonstrated a high microsatellite instability phenotype. We conclude that SSAs are high-risk lesions, with 15% of the SSA patients developing subsequent CRCs or APs with HGD. This incidence is higher than that of the control HP and AP patients, and would support close endoscopic follow-up in patients harboring SSAs.
Cancer Research | 2004
Peter K. Cheung; Bruce Woolcock; Hans Adomat; Margaret Sutcliffe; Terry C. Bainbridge; Edward C. Jones; Douglas Webber; Thomas Kinahan; Marianne D. Sadar; Martin Gleave; Juergen R. Vielkind
Identification of proteomic alterations associated with early stages in the development of prostate cancer may facilitate understanding of progression of this highly variable disease. Matched normal, high-grade prostatic intraepithelial neoplasia (hPIN) and prostate cancer cells of predominantly Gleason grade 3 were procured by laser capture microdissection from serial sections obtained from snap-frozen samples dissected from 22 radical prostatectomy specimens. From these cells, protein profiles were generated by surface-enhanced laser desorption/ionization-time of flight mass spectrometry. A 24-kDa peak was observed at low or high intensity in profiles of prostate cancer cells in 19 of 27 lesions and at low intensity in 3 of 8 hPIN lesions but was not detectable in matched normal cells. SDS-PAGE analysis of prostate cancer and matched normal epithelium confirmed expression of a prostate cancer-specific 24-kDa protein. Mass spectrometry and protein data-based analysis identified the protein as the dimeric form of mature growth differentiation factor 15 (GDF15). The increased expression of mature GDF15 protein in prostate cancer cells cannot be explained on the basis of up-regulation of GDF15 mRNA because reverse transcription-PCR analysis showed similar amounts of transcript in normal, hPIN, and prostate cancer cells that were obtained by laser capture microdissection in the same set of serial sections from which the protein profiles were obtained. Our findings suggest that early prostate carcinogenesis is associated with expression of mature GDF15 protein.
Nephron | 1986
Alex Magil; Douglas Webber; Victor Chan
A 40-year-old man with hepatitis B surface (HBs) antigenemia developed the nephrotic syndrome. Renal biopsy revealed a glomerulonephritis with features of both membranous glomerulonephropathy and IgA nephropathy. Histologically some glomeruli showed mesangial expansion and hypercellularity only, while others contained sclerotic segments. Direct immunofluorescence demonstrated granular IgG-bearing deposits along the peripheral glomerular capillaries and IgA-containing ones in the mesangium. HBs antigen was detected by indirect immunofluorescence both along the glomerular capillary walls and within the mesangium. Granular epimembranous and mesangial deposits were observed by electron microscopy. A few mesangial deposits consisted of spherical particles, 35-100 nm in diameter. Although 3 cases of mixed membranous and IgA nephropathy have been previously reported, this appears to be the first one to be associated with HBs antigenemia.
International Journal of Cancer | 2009
Stephanie Ma; Yuen Piu Chan; Bruce Woolcock; Liang Hu; Ky Wong; Ming-Tat Ling; Terry C. Bainbridge; Douglas Webber; Tim Hon Man Chan; Xin Yuan Guan; Wan L. Lam; Juergen R. Vielkind; Kwok Wah Chan
Identification of genomic alterations associated with the progression of prostate cancer may facilitate the better understanding of the development of this highly variable disease. Matched normal, premalignant high‐grade prostatic intraepithelial neoplasia and invasive prostate carcinoma cells were procured by laser capture microdissection (LCM) from human radical prostatectomy specimens. From these cells, comparative DNA fingerprints were generated by a modified PCR‐based technique called scanning of microdissected archival lesion (SMAL)‐PCR. Recurrent polymorphic fingerprint fragments were used in tagging altered chromosomal regions. Altered regions were found at cytobands 1p31.3, 1q44, 2p23.1, 3p26.3, 3q22.3, 4q22.3, 4q35.2, 5q23.2, 8q22.3, 8q24.13, 9q21.3, 9q22.32, 10q11.21, 11p13, 12p12.1, 13q12.1, 16q12.2 and 18q21.31. Candidate genes in the surrounding area that may possibly harbor mutations that change normal prostatic cells to progress into their tumor stages were proposed. Of these fragments, a 420 bp alteration, absent in all 26 normal samples screened, was observed in 2 tumors. This fragment was cloned, sequenced and localized to chromosome 12p12.1. Within this region, candidate gene sex determining region Y‐box 5 (SOX5) was proposed. Further studies of SOX5 in cell lines, xenografts and human prostate specimens, at both the RNA and protein levels, found overexpression of the gene in tumors. This overexpression was then subsequently found by fluorescent in situ hybridization to be caused by amplification of the region. In conclusion, our results suggest LCM coupled with SMAL‐PCR DNA fingerprinting is a useful method for the screening and identification of chromosomal regions and genes associated with cancer development. Further, overexpression of SOX5 is associated with prostate tumor progression and early development of distant metastasis.
World Journal of Gastrointestinal Oncology | 2010
Hugh J Freeman; Tom Perry; Douglas Webber; Silvia D Chang; Mong-Yang Loh
Malignant disease, including mucinous carcinomas of the colorectum, may complicate long-standing Crohns disease. An 18-year-old male with extensive small and large bowel involvement with Crohns disease developed recurrent peri-rectal fistulous disease that persisted for more than a decade despite pharmacological and surgical therapy as well as later therapy with biological agents. Eventually, an extensive and difficult-to-detect mucinous carcinoma developed in the fistulous tract. Although fistula cancer is rarely described in Crohns disease, use of immunosuppressant and biological agents may play an initiating or exacerbating role in its development or progression. As potent biological agents are frequently used, often to avoid surgical treatment, clinicians should have an increasingly high index of suspicion for this potential complication, especially if fistulous drainage persists and remains refractory to medical therapy.
The Prostate | 2009
Spencer K. Watson; Bruce Woolcock; John N. Fee; Terry C. Bainbridge; Douglas Webber; Thomas Kinahan; Wan L. Lam; Juergen R. Vielkind
Carcinoma of the prostate (CaP) is a serious health problem. The altered molecular mechanisms that lead to this disease are poorly understood.
Journal of Clinical Pathology | 2016
Joyce M. Leo; Steve E. Kalloger; Renata D Peixoto; Nadia S Gale; Douglas Webber; David A. Owen; Daniel John Renouf; David F. Schaeffer
Background Ampullary carcinomata (AC) can be separated into intestinal (IT) or pancreatobiliary (PB) subtypes. Although morphological, immunohistochemical and molecular differentiation of IT and PB have been well documented; the prognostic significance of histological subtype and whether patients with either subtype benefit from differential chemotherapeutic regimens remains unclear. Methods As part of a larger cohort study, patients who underwent resection for AC or pancreatic ductal adenocarcinoma (PDAC) were retrospectively identified. Clinicopathological covariates and outcome were obtained and MUC1, MUC2, CDX2 and CK20 were assessed with immunohistochemistry. Results Of 99 ACs, the resultant immunophenotypes indicated 48% and 22% were IT and PB, respectively. Thirty (30%) cases were quadruple negative (QN). Within the PDAC cohort (N=257), the most prevalent immunophenotype was QN (53%). Subsequently, all QN ACs were classified as PB immunohistochemically yielding 47.5% and 52.5% classified as IT and PB, respectively. Involved regional lymph nodes and elevated T-stage were significantly associated with PB compared with IT AC (p=0.0032 and 0.0396, respectively). Progression-free survival revealed inferior survival for PB versus IT AC (p=0.0156). Conclusions AC can be classified into prognostic groups with unique clinicopathological characteristics using immunohistochemistry. Immunophenotypical similarity of PB and PDAC suggests that treatment regimens similar to those used in PDAC should be explored.
Obstetric Medicine | 2015
Tabassum Firoz; Douglas Webber; Hilary Rowe
Liver disease in pregnancy can be classified as predating, co-incidental or unique to pregnancy. Medications are often overlooked as a significant cause of liver disease. We present the case of a 39-year-old patient who presented at 20 weeks with jaundice, elevated liver enzymes, and abnormal liver function progressing eventually to fulminant hepatic failure. The patient was on methyldopa and labetalol from 12 weeks’ gestational age. Liver biopsy was consistent with drug-induced liver injury. Both methyldopa and labetalol have been associated with hepatotoxicity including liver failure. This case highlights the importance of including medications as a cause of liver failure in pregnant patients.
World Journal of Gastroenterology | 2009
Hugh J Freeman; Douglas Webber
Canadian Journal of Gastroenterology & Hepatology | 2009
Hugh J Freeman; Douglas Webber; Adam T Meneghetti