Hedgehog signaling inhibition blocks growth of resistant tumors through effects on tumor microenvironment.

Hedgehog (Hh) signaling is implicated in bone development and cellular transformation. Here we show that inhibition of Hh pathway activity inhibits tumor growth through effects on the microenvironment. Pharmacologic inhibition of the Hh effector Smoothened (Smo) increased trabecular bone in vivo and inhibited osteoclastogenesis in vitro. In addition, enhanced Hh signaling due to heterozygosity of the Hh inhibitory receptor Patched (Ptch1(+/-)) increased bone resorption, suggesting direct regulation of osteoclast (OC) activity by the Hh pathway. Ptch1(+/-) mice had increased bone metastatic and subcutaneous tumor growth, suggesting that increased Hh activation in host cells promoted tumor growth. Subcutaneous growth of Hh-resistant tumor cells was inhibited by LDE225, a novel orally bioavailable SMO antagonist, consistent with effects on tumor microenvironment. Knockdown of the Hh ligand Sonic Hh (SHH) in these cells decreased subcutaneous tumor growth and decreased stromal cell production of interleukin-6, indicating that tumor-derived Hh ligands stimulated tumor growth in a paracrine fashion. Together our findings show that inhibition of the Hh pathway can reduce tumor burden, regardless of tumor Hh responsiveness, through effects on tumor cells, OCs, and stromal cells within the tumor microenvironment. Hh may be a promising therapeutic target for solid cancers and bone metastases.

[1]  T. Guise,et al.  Cancer to bone: a fatal attraction , 2011, Nature Reviews Cancer.

[2]  P. Schofield,et al.  Hedgehog overexpression is associated with stromal interactions and predicts for poor outcome in breast cancer. , 2011, Cancer research.

[3]  Stephen Gould,et al.  Canonical hedgehog signaling augments tumor angiogenesis by induction of VEGF-A in stromal perivascular cells , 2011, Proceedings of the National Academy of Sciences.

[4]  M. Dewhirst,et al.  Upregulation of VEGF-A and CD24 Gene Expression by the tGLI1 Transcription Factor Contributes to the Aggressive Behavior of Breast Cancer Cells , 2011, Oncogene.

[5]  C. Rudin,et al.  Phase I Trial of Hedgehog Pathway Inhibitor Vismodegib (GDC-0449) in Patients with Refractory, Locally Advanced or Metastatic Solid Tumors , 2011, Clinical Cancer Research.

[6]  L. Matrisian,et al.  TGF-beta promotion of Gli2-induced expression of parathyroid hormone-related protein, an important osteolytic factor in bone metastasis, is independent of canonical Hedgehog signaling. , 2011, Cancer research.

[7]  R. Samant,et al.  Hedgehog Signaling Induced by Breast Cancer Cells Promotes Osteoclastogenesis and Osteolysis* , 2010, The Journal of Biological Chemistry.

[8]  Michael P. Morrissey,et al.  Interfering with Resistance to Smoothened Antagonists by Inhibition of the PI3K Pathway in Medulloblastoma , 2010, Science Translational Medicine.

[9]  M. Tremblay,et al.  New developments in the discovery of small molecule Hedgehog pathway antagonists. , 2010, Current opinion in chemical biology.

[10]  A. Gulino,et al.  Vismodegib, a small-molecule inhibitor of the hedgehog pathway for the treatment of advanced cancers. , 2010, Current opinion in investigational drugs.

[11]  J. Schneider,et al.  Dissection of platelet and myeloid cell defects by conditional targeting of the β3‐integrin subunit , 2010, FASEB journal : official publication of the Federation of American Societies for Experimental Biology.

[12]  C. Rudin,et al.  Smoothened Mutation Confers Resistance to a Hedgehog Pathway Inhibitor in Medulloblastoma , 2009, Science.

[13]  David Allard,et al.  Inhibition of Hedgehog Signaling Enhances Delivery of Chemotherapy in a Mouse Model of Pancreatic Cancer , 2009, Science.

[14]  Jeanne A. Ferguson,et al.  Discovery of a potent and orally active hedgehog pathway antagonist (IPI-926). , 2009, Journal of medicinal chemistry.

[15]  S. Hilsenbeck,et al.  Cyclopamine inhibition of human breast cancer cell growth independent of Smoothened (Smo) , 2009, Breast Cancer Research and Treatment.

[16]  W. Zou,et al.  CD47 regulates bone mass and tumor metastasis to bone. , 2009, Cancer research.

[17]  H. Tian,et al.  Hedgehog signaling is restricted to the stromal compartment during pancreatic carcinogenesis , 2009, Proceedings of the National Academy of Sciences.

[18]  Masafumi Nakamura,et al.  The Hedgehog pathway is a possible therapeutic target for patients with estrogen receptor-negative breast cancer. , 2009, Anticancer research.

[19]  C. Rudin,et al.  Abstract LB-138: Efficacy data of GDC-0449, a systemic Hedgehog pathway antagonist, in a first-in-human, first-in-class Phase I study with locally advanced, multifocal or metastatic basal cell carcinoma patients , 2008 .

[20]  Kozo Nakamura,et al.  Patched1 haploinsufficiency increases adult bone mass and modulates Gli3 repressor activity. , 2008, Developmental cell.

[21]  T. Clemens,et al.  Hedgehog signaling in mature osteoblasts regulates bone formation and resorption by controlling PTHrP and RANKL expression. , 2008, Developmental cell.

[22]  Hua Tian,et al.  A paracrine requirement for hedgehog signalling in cancer , 2008, Nature.

[23]  T. Curran,et al.  Transient inhibition of the Hedgehog pathway in young mice causes permanent defects in bone structure. , 2008, Cancer cell.

[24]  M. Hollingsworth,et al.  Cancer metastasis facilitated by developmental pathways: Sonic hedgehog, Notch, and bone morphogenic proteins , 2007, Journal of cellular biochemistry.

[25]  M. Scott,et al.  Patching the gaps in Hedgehog signalling , 2007, Nature Cell Biology.

[26]  Monika Engelhardt,et al.  Essential role of stromally induced hedgehog signaling in B-cell malignancies , 2007, Nature Medicine.

[27]  T. Shimokawa,et al.  Inhibition of GLI-mediated transcription and tumor cell growth by small-molecule antagonists , 2007, Proceedings of the National Academy of Sciences.

[28]  Y. Maeda,et al.  Indian Hedgehog produced by postnatal chondrocytes is essential for maintaining a growth plate and trabecular bone , 2007, Proceedings of the National Academy of Sciences.

[29]  C. Iacobuzio-Donahue,et al.  Blockade of hedgehog signaling inhibits pancreatic cancer invasion and metastases: a new paradigm for combination therapy in solid cancers. , 2007, Cancer research.

[30]  J. Taipale,et al.  Hedgehog signaling , 2007, Journal of Cell Science.

[31]  Ming Zhao,et al.  The hedgehog signaling molecule Gli2 induces parathyroid hormone-related peptide expression and osteolysis in metastatic human breast cancer cells. , 2006, Cancer research.

[32]  G. Page,et al.  Hedgehog signaling and response to cyclopamine differs in epithelial and stromal cells in benign breast and breast cancer , 2006, Cancer biology & therapy.

[33]  L. Ramalho,et al.  p63 correlates with both BRCA1 and cytokeratin 5 in invasive breast carcinomas: further evidence for the pathogenesis of the basal phenotype of breast cancer , 2005, Histopathology.

[34]  D. Piwnica-Worms,et al.  CXCR4 Regulates Growth of Both Primary and Metastatic Breast Cancer , 2004, Cancer Research.

[35]  Masatoshi Nomura,et al.  Hedgehog Signaling Pathway is a New Therapeutic Target for Patients with Breast Cancer , 2004, Cancer Research.

[36]  Helen Baines,et al.  Suppression of the Shh pathway using a small molecule inhibitor eliminates medulloblastoma in Ptc1(+/-)p53(-/-) mice. , 2004, Cancer cell.

[37]  A. McMahon,et al.  Ihh signaling is directly required for the osteoblast lineage in the endochondral skeleton , 2004, Development.

[38]  S. Morrison,et al.  Prospective identification of tumorigenic breast cancer cells , 2003, Proceedings of the National Academy of Sciences of the United States of America.

[39]  N. Ueno,et al.  Sonic hedgehog is involved in osteoblast differentiation by cooperating with BMP‐2 , 2002, Journal of cellular physiology.

[40]  A. McMahon,et al.  Genetic manipulation of hedgehog signaling in the endochondral skeleton reveals a direct role in the regulation of chondrocyte proliferation. , 2001, Development.

[41]  J. Taipale,et al.  The Hedgehog and Wnt signalling pathways in cancer , 2001, Nature.

[42]  A. McMahon,et al.  Indian hedgehog signaling regulates proliferation and differentiation of chondrocytes and is essential for bone formation. , 1999, Genes & development.

[43]  M. Scott,et al.  Basal cell carcinomas in mice overexpressing sonic hedgehog. , 1997, Science.

[44]  H. Ohuchi,et al.  Fibroblasts expressing Sonic hedgehog induce osteoblast differentiation and ectopic bone formation , 1997, FEBS letters.

[45]  B F Boyce,et al.  Evidence for a causal role of parathyroid hormone-related protein in the pathogenesis of human breast cancer-mediated osteolysis. , 1996, The Journal of clinical investigation.

[46]  H. Ozawa,et al.  Comparison of the effects of intermittent and continuous administration of human parathyroid hormone(1-34) on rat bone. , 1995, Bone.

[47]  Andrew P. McMahon,et al.  Sonic hedgehog, a member of a family of putative signaling molecules, is implicated in the regulation of CNS polarity , 1993, Cell.

[48]  C. Albarracin,et al.  Hedgehog Overexpression Is Associated with Stromal Interactions and Predicts for Poor Outcome in Breast Cancer: O'Toole SA, Machalek DA, Shearer RF, et al (Garvan Inst of Med Res, Darlinghurst, New South Wales, Australia; et al) Cancer Res 71:4002-4014, 2011§ , 2011 .

[49]  W. Bushman Hedgehog Signaling in Development and Cancer , 2007 .

[50]  Andrew P McMahon,et al.  Developmental roles and clinical significance of hedgehog signaling. , 2003, Current topics in developmental biology.

[51]  鵜澤 豊暢 Comparison of the effects of intermittent and continuous administration of human parathyroid hormone (1-34) on rat bone , 1996 .