Schulich school of Medicine and Dentistry logo Gastroenterology Schulich School of Medicine & Dentistry

Samuel Asfaha

Samuel Asfaha

Contact Information

Rm E6-325, Victoria Hospital
800 Commissioners Road East
London, ON N6A 5W9
Phone: 519.685.8500 ext 53293
Fax: 519.667.6820
The Asfaha Lab Website

Research Interests/Specialization

Stem Cells
Colorectal Cancer
Gastrointestinal Stem Cell Biology

Dr. Asfaha completed his undergraduate training in molecular biology, followed by his Ph.D in mucosal inflammation at the University of Calgary. His clinical training includes his MD degree from the University of Calgary, residency in Internal Medicine at the University of Alberta and his fellowship in Gastroenterology at University of Calgary. Following his clinical training, Dr. Asfaha completed postdoctoral research training at Columbia University in New York City, where he subsequently was promoted to junior faculty as an Instructor in the Division of Digestive &Liver Diseases. While at Columbia University he conducted ground breaking research into the cellular origin of colorectal and gastric cancer.

Dr. Asfaha was recruited to the Schulich School of Medicine & Dentistry at the University of Western Ontario and Lawson Health Institute as an Assistant Professor and Schulich Clinician-scientist. His research is focused on targeting the cellular origin of colorectal cancer and improving tissue repair in inflammatory bowel diseases (IBD). His expertise and accomplishments are illustrated by numerous national and international awards he has received and his publications.


Selected Publications


1. Reuter BK, Asfaha S, Buret A, Sharkey KA, Wallace JL. Exacerbation of inflammation-associated colonic injury in rat through inhibition of cyclooxygenase-2. J Clin Invest, 1996 Nov 1; 98 (9): 2076-85, Co-Principal Author, DOI: 10.1172/JCI119013.

2. Ferraz JG, Sharkey KA, Reuter BK, Asfaha S, Tigley AW, Brown ML, McKnight W, Wallace JL. Induction of cyclooxygenase 1 and 2 in the rat stomach during endotoxemia: role in resistance to damage. Gastroenterology, 1997 Jul 1; 113 (1): 195-204, Coauthor

3. Davies NM, Sharkey KA, Asfaha S, Macnaughton WK, Wallace JL. Aspirin causes rapid up-regulation of cyclo-oxygenase-2 expression in the stomach of rats. Aliment Pharmacol Ther, 1997 Dec 1; 11 (6): 1101-8, Coauthor

4. Wallace JL, McKnight W, Asfaha S, Liu DY. Reduction of acute and reactivated colitis in rats by an inhibitor of neutrophil activation. Am J Physiol, 1998 May 1; 274 (5 Pt 1): G802-8, Coauthor

5. Wallace JL, Bak A, McKnight W, Asfaha S, Sharkey KA, MacNaughton WK. Cyclooxygenase 1 contributes to inflammatory responses in rats and mice: implications for gastrointestinal toxicity. Gastroenterology, 1998 Jul 1; 115 (1): 101-9, Coauthor

6. Asfaha S, Bell CJ, Wallace JL, MacNaughton WK. Prolonged colonic epithelial hyporesponsiveness after colitis: role of inducible nitric oxide synthase. Am J Physiol, 1999 Mar 1; 276 (3 Pt 1): G703-10, Principal Author

7. Wallace JL, Vergnolle N, Muscar MN, Asfaha S, Chapman K, McKnight W, Del Soldato P, Morelli A, Fiorucci S. Enhanced anti-inflammatory effects of a nitric oxide-releasing derivative of mesalamine in rats. Gastroenterology, 1999 Sep 1; 117 (3): 557-66, Coauthor

8. Muscará MN, McKnight W, Asfaha S, Wallace JL. Wound collagen deposition in rats: effects of an NO-NSAID and a selective COX-2 inhibitor. Br J Pharmacol, 2000 Feb 1; 129 (4): 681-6, Coauthor, DOI: 10.1038/sj.bjp.0703112.

9. Muscará MN, Vergnolle N, Lovren F, Triggle CR, Elliott SN, Asfaha S, Wallace JL. Selective cyclo-oxygenase-2 inhibition with celecoxib elevates blood pressure and promotes leukocyte adherence. Br J Pharmacol, 2000 Apr 1; 129 (7): 1423-30, Coauthor, DOI: 10.1038/sj.bjp.0703232.

10. Asfaha S, MacNaughton WK, Appleyard CB, Chadee K, Wallace JL. Persistent epithelial dysfunction and bacterial translocation after resolution of intestinal inflammation. Am J Physiol Gastrointest Liver Physiol, 2001 Sep 1; 281 (3): G635-44, Principal Author

11. Asfaha S, Brussee V, Chapman K, Zochodne DW, Vergnolle N. Proteinase-activated receptor-1 agonists attenuate nociception in response to noxious stimuli. Br J Pharmacol, 2002 Mar 1; 135 (5): 1101-6, Principal Author, DOI: 10.1038/sj.bjp.0704568.

12. Ulanova M, Marcet-Palacios M, Muñoz S, Asfaha S, Kim MK, Schreiber AD, Befus AD. Involvement of Syk kinase in TNF-induced nitric oxide production by airway epithelial cells. Biochem Biophys Res Commun, 2006 Dec 15; 351 (2): 431-7, Coauthor, DOI: 10.1016/j.bbrc.2006.10.073.

13. Asfaha S, Almansori M, Qarni U, Gutfreund KS. Plasmapheresis for hemolytic crisis and impending acute liver failure in Wilson disease. J Clin Apher, 2007 Jan 1; 22 (5): 295-8, Principal Author, DOI: 10.1002/jca.20140.

14. Ulanova M, Asfaha S, Stenton G, Lint A, Gilbertson D, Schreiber A, Befus D. Involvement of Syk protein tyrosine kinase in LPS-induced responses in macrophages. J Endotoxin Res, 2007 Jan 1; 13 (2): 117-25, Co-Principal Author, DOI: 10.1177/0968051907079125.

15. Asfaha S, Cenac N, Houle S, Altier C, Papez MD, Nguyen C, Steinhoff M, Chapman K, Zamponi GW, Vergnolle N. Protease-activated receptor-4: a novel mechanism of inflammatory pain modulation. Br J Pharmacol, 2007 Jan 1; 150 (2): 176-85, Principal Author, DOI: 10.1038/sj.bjp.0706975.

16. Asfaha S, Alqahtani S, Hilsden RJ, MacLean AR, Beck PL. Assessment of endoscopic training of general surgery residents in a North American health region. Gastrointest Endosc, 2008 Dec 1; 68 (6): 1056-62, Principal Author, DOI: 10.1016/j.gie.2008.03.1088.

17. Wang SS, Asfaha S, Okumura T, Betz KS, Muthupalani S, Rogers AB, Tu S, Takaishi S, Jin G, Yang X, Wu DC, Fox JG, Wang TC. Fibroblastic colony-forming unit bone marrow cells delay progression to gastric dysplasia in a helicobacter model of gastric tumorigenesis. Stem Cells, 2009 Sep 1; 27 (9): 2301-11, Co-Principal Author, DOI: 10.1002/stem.165.

18. Grosberg LE, Radosevich AJ, Asfaha S, Wang TC, Hillman EM. Spectral characterization and unmixing of intrinsic contrast in intact normal and diseased gastric tissues using hyperspectral two-photon microscopy. PLoS One, 2011 Jan 1; 6 (5): e19925, Coauthor, DOI: 10.1371/journal.pone.0019925.

19. Yang XD, Ai W, Asfaha S, Bhagat G, Friedman RA, Jin G, Park H, Shykind B, Diacovo TG, Falus A, Wang TC. Histamine deficiency promotes inflammation-associated carcinogenesis through reduced myeloid maturation and accumulation of CD11b+Ly6G+ immature myeloid cells. Nat Med, 2011 Jan 1; 17 (1): 87-95, Co-Principal Author, DOI: 10.1038/nm.2278.

20. Takaishi S, Shibata W, Tomita H, Jin G, Yang X, Ericksen R, Dubeykovskaya Z, Asfaha S, Quante M, Betz KS, Shulkes A, Wang TC. In vivo analysis of mouse gastrin gene regulation in enhanced GFP-BAC transgenic mice. Am J Physiol Gastrointest Liver Physiol, 2011 Feb 1; 300 (2): G334-44, Coauthor, DOI: 10.1152/ajpgi.00134.2010.

21. Quante M, Bhagat G, Abrams JA, Marache F, Good P, Lee MD, Lee Y, Friedman R, Asfaha S, Dubeykovskaya Z, Mahmood U, Figueiredo JL, Kitajewski J, Shawber C, Lightdale CJ, Rustgi AK, Wang TC. Bile acid and inflammation activate gastric cardia stem cells in a mouse model of Barrett-like metaplasia. Cancer Cell, 2012 Jan 17; 21 (1): 36-51, Coauthor, DOI: 10.1016/j.ccr.2011.12.004.

22. Asfaha S, Dubeykovskiy AN, Tomita H, Yang X, Stokes S, Shibata W, Friedman RA, Ariyama H, Dubeykovskaya ZA, Muthupalani S, Ericksen R, Frucht H, Fox JG, Wang TC. Mice that express human interleukin-8 have increased mobilization of immature myeloid cells, which exacerbates inflammation and accelerates colon carcinogenesis. Gastroenterology, 2013 Jan 1; 144 (1): 155-66, Principal Author, DOI: 10.1053/j.gastro.2012.09.057.

23. Shibata W, Ariyama H, Westphalen CB, Worthley DL, Muthupalani S, Asfaha S, Dubeykovskaya Z, Quante M, Fox JG, Wang TC. Stromal cell-derived factor-1 overexpression induces gastric dysplasia through expansion of stromal myofibroblasts and epithelial progenitors. Gut, 2013 Feb 1; 62 (2): 192-200, Coauthor, DOI: 10.1136/gutjnl-2011-301824.

24. Jin G, Westphalen CB, Hayakawa Y, Worthley DL, Asfaha S, Yang X, Chen X, Si Y, Wang H, Tailor Y, Friedman RA, Wang TC. Progastrin stimulates colonic cell proliferation via CCK2R- and β-arrestin-dependent suppression of BMP2. Gastroenterology, 2013 Oct 1; 145 (4): 820-30.e10, Coauthor, DOI: 10.1053/j.gastro.2013.07.034.

25. Westphalen CB, Asfaha S, Hayakawa Y, Takemoto Y, Lukin DJ, Nuber AH, Brandtner A, Setlik W, Remotti H, Muley A, Chen X, May R, Houchen CW, Fox JG, Gershon MD, Quante M, Wang TC. Long-lived intestinal tuft cells serve as colon cancer-initiating cells. J Clin Invest, 2014 Mar 1; 124 (3): 1283-95, Principal Author, DOI: 10.1172/JCI73434.

26. Worthley DL, Churchill M, Compton JT, Tailor Y, Rao M, Si Y, Levin D, Schwartz MG, Uygur A, Hayakawa Y, Gross S, Renz BW, Setlik W, Martinez AN, Chen X, Nizami S, Lee HG, Kang HP, Caldwell JM, Asfaha S, Westphalen CB, Graham T, Jin G, Nagar K, Wang H, Kheirbek MA, Kolhe A, Carpenter J, Glaire M, Nair A, Renders S, Manieri N, Muthupalani S, Fox JG, Reichert M, Giraud AS, Schwabe RF, Pradere JP, Walton K, Prakash A, Gumucio D, Rustgi AK, Stappenbeck TS, Friedman RA, Gershon MD, Sims P, Grikscheit T, Lee FY, Karsenty G, Mukherjee S, Wang TC. Gremlin 1 identifies a skeletal stem cell with bone, cartilage, and reticular stromal potential. Cell, 2015 Jan 15; 160 (1-2): 269-84, Principal Author, DOI: 10.1016/j.cell.2014.11.042.

27. Hayakawa Y, Jin G, Wang H, Chen X, Westphalen CB, Asfaha S, Renz BW, Ariyama H, Dubeykovskaya ZA, Takemoto Y, Lee Y, Muley A, Tailor Y, Chen D, Muthupalani S, Fox JG, Shulkes A, Worthley DL, Takaishi S, Wang TC. CCK2R identifies and regulates gastric antral stem cell states and carcinogenesis. Gut, 2015 Apr 1; 64 (4): 544-53, Coauthor, DOI: 10.1136/gutjnl-2014-307190.