The Hedgehog Pathway Conditions the Bone Microenvironment for Osteolytic Metastasis of Breast Cancer

Table 1

Cancers with aberrant activation of Hh signaling.

Milieu	Hh Signaling caused by	Molecule(s) involved	Type of cancer	Reference
I	Overexpression	GLI1	Glioblastoma	[30]
	Mutations	PTCH	Basal cell carcinoma (BCC)	[31, 32]
		SMO	Basal cell carcinoma	[31, 32]
		PTCH	Medulloblastoma	[33]
		PTCH	Rhabdomyosarcoma	[34]
		PTCH1	Gorlin syndrome BCC	[35, 36]
		SMO & PTCH1	Nonfamilial BCC	[37]
II	Ligand-dependent autocrine		Breast	[22]
			Pancreatic	[38]
			Lung cancer	[39]
			Oesophagal	[40]
			Prostate	[41]
			Gastric adenocarcinoma	[42]
			Colorectal	[43]
			Hepatocellular adenocarcinoma	[44]
			Ovarian carcinoma	[45, 49]
	Ligand-dependent paracrine		Pancreatic	[46–48]

Milieu I represents the microenvironment of the primary tumor; Milieu II represents the microenvironment at the metastatic site.