PURPOSE: Local breast cancer relapse after breast-saving surgery and radiotherapy is associated with increased risk of distant metastasis formation. The mechanisms involved remain largely elusive. We used the well-characterized 4T1 syngeneic, orthotopic breast cancer model to identify novel mechanisms of postradiation metastasis. EXPERIMENTAL DESIGN: 4T1 cells were injected in 20 Gy preirradiated mammary tissue to mimic postradiation relapses, or in nonirradiated mammary tissue, as control, of immunocompetent BALB/c mice. Molecular, biochemical, cellular, histologic analyses, adoptive cell transfer, genetic, and pharmacologic interventions were carried out. RESULTS: Tumors growing in preirradiated mammary tissue had reduced angiogenesis and were more hypoxic, invasive, and metastatic to lung and lymph nodes compared with control tumors. Increased metastasis involved the mobilization of CD11b(+)c-Kit(+)Ly6G(high)Ly6C(low)(Gr1(+)) myeloid cells through the HIF1-dependent expression of Kit ligand (KitL) by hypoxic tumor cells. KitL-mobilized myeloid cells homed to primary tumors and premetastatic lungs, to give rise to CD11b(+)c-Kit(-) cells. Pharmacologic inhibition of HIF1, silencing of KitL expression in tumor cells, and inhibition of c-Kit with an anti-c-Kit-blocking antibody or with a tyrosine kinase inhibitor prevented the mobilization of CD11b(+)c-Kit(+) cells and attenuated metastasis. C-Kit inhibition was also effective in reducing mobilization of CD11b(+)c-Kit(+) cells and inhibiting lung metastasis after irradiation of established tumors. CONCLUSIONS: Our work defines KitL/c-Kit as a previously unidentified axis critically involved in promoting metastasis of 4T1 tumors growing in preirradiated mammary tissue. Pharmacologic inhibition of this axis represents a potential therapeutic strategy to prevent metastasis in breast cancer patients with local relapses after radiotherapy.
PURPOSE: Local breast cancer relapse after breast-saving surgery and radiotherapy is associated with increased risk of distant metastasis formation. The mechanisms involved remain largely elusive. We used the well-characterized 4T1 syngeneic, orthotopic breast cancer model to identify novel mechanisms of postradiation metastasis. EXPERIMENTAL DESIGN: 4T1 cells were injected in 20 Gy preirradiated mammary tissue to mimic postradiation relapses, or in nonirradiated mammary tissue, as control, of immunocompetent BALB/c mice. Molecular, biochemical, cellular, histologic analyses, adoptive cell transfer, genetic, and pharmacologic interventions were carried out. RESULTS:Tumors growing in preirradiated mammary tissue had reduced angiogenesis and were more hypoxic, invasive, and metastatic to lung and lymph nodes compared with control tumors. Increased metastasis involved the mobilization of CD11b(+)c-Kit(+)Ly6G(high)Ly6C(low)(Gr1(+)) myeloid cells through the HIF1-dependent expression of Kit ligand (KitL) by hypoxic tumor cells. KitL-mobilized myeloid cells homed to primary tumors and premetastatic lungs, to give rise to CD11b(+)c-Kit(-) cells. Pharmacologic inhibition of HIF1, silencing of KitL expression in tumor cells, and inhibition of c-Kit with an anti-c-Kit-blocking antibody or with a tyrosine kinase inhibitor prevented the mobilization of CD11b(+)c-Kit(+) cells and attenuated metastasis. C-Kit inhibition was also effective in reducing mobilization of CD11b(+)c-Kit(+) cells and inhibiting lung metastasis after irradiation of established tumors. CONCLUSIONS: Our work defines KitL/c-Kit as a previously unidentified axis critically involved in promoting metastasis of 4T1 tumors growing in preirradiated mammary tissue. Pharmacologic inhibition of this axis represents a potential therapeutic strategy to prevent metastasis in breast cancerpatients with local relapses after radiotherapy.
Authors: Patrycja Nowak-Sliwinska; Kari Alitalo; Elizabeth Allen; Andrey Anisimov; Alfred C Aplin; Robert Auerbach; Hellmut G Augustin; David O Bates; Judy R van Beijnum; R Hugh F Bender; Gabriele Bergers; Andreas Bikfalvi; Joyce Bischoff; Barbara C Böck; Peter C Brooks; Federico Bussolino; Bertan Cakir; Peter Carmeliet; Daniel Castranova; Anca M Cimpean; Ondine Cleaver; George Coukos; George E Davis; Michele De Palma; Anna Dimberg; Ruud P M Dings; Valentin Djonov; Andrew C Dudley; Neil P Dufton; Sarah-Maria Fendt; Napoleone Ferrara; Marcus Fruttiger; Dai Fukumura; Bart Ghesquière; Yan Gong; Robert J Griffin; Adrian L Harris; Christopher C W Hughes; Nan W Hultgren; M Luisa Iruela-Arispe; Melita Irving; Rakesh K Jain; Raghu Kalluri; Joanna Kalucka; Robert S Kerbel; Jan Kitajewski; Ingeborg Klaassen; Hynda K Kleinmann; Pieter Koolwijk; Elisabeth Kuczynski; Brenda R Kwak; Koen Marien; Juan M Melero-Martin; Lance L Munn; Roberto F Nicosia; Agnes Noel; Jussi Nurro; Anna-Karin Olsson; Tatiana V Petrova; Kristian Pietras; Roberto Pili; Jeffrey W Pollard; Mark J Post; Paul H A Quax; Gabriel A Rabinovich; Marius Raica; Anna M Randi; Domenico Ribatti; Curzio Ruegg; Reinier O Schlingemann; Stefan Schulte-Merker; Lois E H Smith; Jonathan W Song; Steven A Stacker; Jimmy Stalin; Amber N Stratman; Maureen Van de Velde; Victor W M van Hinsbergh; Peter B Vermeulen; Johannes Waltenberger; Brant M Weinstein; Hong Xin; Bahar Yetkin-Arik; Seppo Yla-Herttuala; Mervin C Yoder; Arjan W Griffioen Journal: Angiogenesis Date: 2018-08 Impact factor: 9.596
Authors: Luis F Miranda; Claudia O Rodrigues; Shalini Ramachandran; Eneida Torres; Jian Huang; Jammie Klim; Dorothy Hehre; Ian McNiece; Joshua M Hare; Cleide Y Suguihara; Karen C Young Journal: Pediatr Res Date: 2013-10-23 Impact factor: 3.756