Table 1.

Ligand	Function	Reference
WNT1	Located on chromosome 12q13 Proto-oncogene Involved in chromosomal rearrangements in a wide range of cancers Involved in cell proliferation, motility, patterning, embryonic development, fate determination, and carcinogenesis	Rijsewijk et al., 1987; Arheden et al., 1988
WNT2A (WNT13)	Located on chromosome 7q31.2 WNT2 was shown to have a similar protein sequence, biochemical properties, and transforming potential as WNT1 Involved in angiogenesis, overexpressed in colorectal cancer, and upregulated in melanoma One study suggests that use of a monoclonal antibody against WNT2 may be useful as a treatment for malignant melanoma as it was shown to induce apoptosis in human melanoma cells overexpressing WNT2	Wainwright et al., 1988; Blasband et al., 1992; Klein et al., 2009; Park et al., 2009; Kashani-Sabet et al., 2009; You et al., 2004
WNT2B	Located on chromosome 1p13 372 amino acids, including a signal peptide, two potential N-glycosylation sites, and 24 cysteine residues Detected in the heart, placenta, brain, prostate, lung, testis, ovary, small intestine, and colon of adult human, as well as the lung, kidney, and brain of fetal human Role in cancer, including head and neck squamous cell carcinomas, breast cancer, and acute lymphoblastic leukemia	Katoh et al., 1996; Rhee et al., 2002; Benhal et al., 2006; Khan et al., 2007
WNT3A	Located on chromosome 1q42 Induces Dvl phosphorylation, β-catenin stabilization, and TCF4 transcriptional activity WNT3A expressing B16 mouse melanoma cells exhibit decreased tumor size and decreased metastasis when implanted into mice Upregulates genes implicated in melanocyte differentiation, several of which are downregulated with melanoma progression May alter melanoma cell fate to a less proliferative and less aggressive phenotype	Roelink et al., 1993; Chen et al., 2008; Chein et al., 2009
WNT4	Located on chromosome 1p36.23-p35.1 Major role in development which affects morphogenesis in the zebrafish embro when misexpressed, including: misfolding in the brain, cyclopia, and an anteriorly forking notochord Important in kidney pattern formation in Xenopus and cell migration in the developing mammalian gonad In pituitary adenoma cells, WNT4 is involved in proliferation and survival, acting through a β-catenin independent pathway Acts as an early granulosa cell tumor marker in the testis	Ungar, Kelly, and Moon, 1995; Carroll, Wallingford, and Vize, 1999; Jeays-Ward et al., 2003; Miyakoshi et al., 2008; Boyer et al., 2009
WNT5A	Located on chromosome 3p21-p14 Major role in melanoma proliferation and invasion Microarray studies and SAGE analysis demonstrated the upregulation of WNT5A in metastatic cells, as well as the importance of intracellular calcium expression Melanoma cells overexpressing WNT5A, through transfection with stably expressing constructs, have been shown to increase cell motility and invasive potential Contributes to the epithelial to mesenchymal transition through activation of the non-canonical pathway and the inhibition of metastatic suppressors Regulates the expression of tumor antigens via the expression of STAT3 Effects motility and invasion through filamin A cleavage via calpains In addition to melanoma, WNT5A has been shown to be important in pancreatic cancer, breast cancer, and ovarian cancer	Bittner et al., 2000; Weeraratna et al., 2004; Weeraratna et al., 2002; Dissanayake et al., 2007; Dissanayake et al., 2008; O’Connell et al., 2009; Schwartz et al., 2009; Ford et al., 2009; Badiglian Filho et al., 2009
WNT5B	Consists of 4 exons and is located on human chromosome 12p13.3 Moderately expressed in adult prostate and fetal brain, and weakly expressed in fetal lung, kidney, adult liver, small intestine, and ovary Important in osteosarcomas and is overexpressed in leiomyoma, esophageal, and breast cancer cells	Saitoh and Katoh, 2001; Morioka et al., 2009; Mangioni et al., 2005; Saitoh and Katoh, 2002
WNT6	First isolated in xenopus and mapped to human chromosome band 2q35 by in situ hybridization Important during heart muscle generation and amniote neural crest induction through the non-canonical signaling pathway	Wolda and Moon, 1992; Rankin et al., 1999; Schmidt et al., 2007; Lavery et al., 2008
WNT7A	Located on chromosome 3p25 Important in dorsoventral patterning in the limb Recently shown to activate the planar cell polarity pathway to drive the symmetric expansion of satellite stem cells, subsequently regulating the regenerative potential of muscle Activates the JNK pathway in non-small cell lung cancer cells	Riddle et al., 1995; Le Grand et al., 2009; Heasley and Winn, 2008
WNT7B	Located on chromosome 22q13 Stimulates embryonic lung growth by increasing the replication of epithelium and mesenchyme In melanoma, WNT7B is present, but at variable levels, whereas in nevi, WNT7B has been shown to be strongly expressed	Rajagopal et al., 2008; Pham et al., 2003
WNT8A	Located on chromosome 5q31 Activates casein kinase Iε (CKIε), a positive regulator of the canonical Wnt pathway	Swiatek et al., 2004
WNT8B	Located on chromosome 10q24 WNT8B plays a key role in regulating proliferation of lens stem/progenitor cells and during early stages of fiber cell differentiation	Martinez et al., 2009
WNT9A (14)	Located on chromosome 1q42 Involved in canonical signaling, mediated by FZD7/9 WNT9A is required for the proper morphogenesis of chick hepatocellular cords and the proliferation of hepatoblasts/hepatocytes Involved in glycogen accumulation in hepatocytes	Matsumoto et al., 2008
WNT9B (15)	Located on chromosome 17q21 Mutated in multifactorial non-syndromic cleft lip Distinct roles in directing morphogenetic movements of developing branchial arch elements	Juriloff et al., 2006; Jezewski et al., 2008
WNT10A	Located on chromosome 2q35 Mutation associated with a complete Odonto-Onycho- Dermal Dysplasia syndrome Target of epigenetic inactivation in primary glial tumors and tumor cell lines	Nawaz et al., 2009; Ordway et al., 2006
WNT10B (WNT12)	Located chromosome: 12q13 Highly expressed in nevi and also in melanomas characterized by small, uniform cells and by large, pleomorphic cells	Pham et al., 2003
WNT11	Located on chromosome 11q13.5 A non-canonical WNT ligand Functions in gastrulation by controlling cell cohesion Highly expressed in neuroblastomas	Katoh, 2005; Ulrich et al., 2005; Wai et al., 2002
WNT16	Located on chromosome 7q31 Involved in human acute lymphoblastoid leukemia Aberrant expression of WNT16 may be a key step in leukemogenesis in t(1;19)-positive pre-B leukemia cells	Mazieres et al., 2005; Casagrande et al., 2006