Beta catenin is a transcriptional co-regulator and an adapter protein for cellular adhesion; it comprises part of the Wnt signaling pathway and intracellular levels of beta-catenin are regulated by its phosphorylation, ubiquitination and proteosomal degradation. Accumulation of nuclear beta catenin can lead to a tumoral phenotype and oncogenic transformation in a variety of solid tumors. Various oncogenic mutants of beta catenin have been found in different tumor types which alter its degradation, leading to its accumulation and promoting tumor growth. Some of these mutations are located at the N-terminus of the protein at the sites of phosphorylation which normally regulate its degradation. Interestingly, in a recent study, 38% of patients with myelodysplastic syndromes or acute myeloid leukaemia, showed increased β-catenin signalling and nuclear accumulation of beta catenin in osteoblasts was associated with increased Notch signalling in haematopoietic cells consistent with a model where abnormalities of osteolineage cells are associated with myeloid malignancies. In addition, aberrant Wnt siganling has been reported to play a role in chronic myeloid leukemia, acute lymphoblastic leukemia and non-hodgkin lymphomas. Inhibition of beta catenin using small molecule inhibitors is currently being investigated in various tumor types. Recent studies suggest that targeting of the Wnt pathway and beta catenin may be promising targets in the therapy of acute myeloid leukemia.

CTNNB1 encodes the protein b-catenin, a transcriptional activator involved in the WNT signaling pathway. Somatic gain-of-function mutations in CTNNB1 result in aberrant accumulation of the b-catenin protein and are prevalent in a wide range of solid tumors, including endometrial carcinoma, ovarian carcinoma, hepatocellular carcinoma, and colorectal carcinoma, among others. Genetic alterations in CTNNB1 have been identified in 4% of non-small cell lung cancers. The CTNNB1 S437F mutation has been reported as pathogenic in lung adenocarcinoma, but no real progress has been made in targeting oncogenic mutant forms of CTNNB1 in lung cancer. However, CTNNB1 mutation-positive cancers are presumed to be resistant to pharmacologic inhibition of upstream components of the WNT pathway, instead requiring direct inhibition of b-catenin function. In one study pharmacological inhibition of b-catenin suppressed EGFR-L858R/T790M mutated lung tumor and genetic deletion of the b-catenin gene dramatically reduced lung tumor formation in transgenic mice, suggesting that b-catenin plays an essential role in lung tumorigenesis and that targeting the b-catenin pathway may provide novel strategies to prevent lung cancer development or overcome resistance to EGFR TKIs. These results should be interpreted in the clinical context.

The cytoplasmic b-catenin protein is implicated as a cell-cell adhesion regulator coupled with cadherin and is considered as a member in the wingless/Wnt signal transduction pathway. Mutations in CTNNB1, the gene encoding b-catenin, tend to impact or even eliminate APC-dependent serine and threonine phosphorylation sites in exon 3, resulting in oncogenic stabilization of the protein. Mutations in the b-catenin gene are uncommon in NSCLC occurring in about 1-4% of the cases. CTNNB1 S37C is a gain of function mutation, has been described in 0.3% of non-small cell lung carcinomas and is likely oncogenic. However, its prognostic and therapeutic significance remains to be fully elucidated.

Beta catenin is a transcriptional co-regulator and an adapter protein for cellular adhesion; it comprises part of the Wnt signaling pathway and intracellular levels of beta-catenin are regulated by its phosphorylation, ubiquitination and proteosomal degradation. Accumulation of nuclear beta catenin can lead to a tumoral phenotype and oncogenic transformation in a variety of solid tumors. Various oncogenic mutants of beta catenin have been found in different tumor types which alter its degradation, leading to its accumulation and promoting tumor growth. CTNNB1 mutations in prostate cancer occur rarely, in only 2-5% of cases. Currently, the function of b-Catenin in human prostate cancer continues to be explored. In the context of prostate, b-Catenin may modulate the androgen receptor (AR) pathway. This particular variant S33F is predicted to confer a gain of function to the CTNNB1 protein as demonstrated by nuclear accumulation of CTNNB1. Clinical correlation is recommended.

CTNNB1 encodes b-catenin, a transcriptional co-regulator and an adapter protein for cellular adhesion involved in the WNT signaling pathway. Somatic gain-of-function mutations in CTNNB1 result in aberrant accumulation of the b-catenin protein and are prevalent in a wide range of solid tumors, including uterine/endometrial carcinoma, ovarian, hepatocellular carcinoma, and colorectal carcinoma, among others. CTNNB1 mutations are particularly common in colorectal carcinomas associated with hereditary non-polyposis colon cancer syndrome and wild type APC gene, and are extremely rare in sporadic colorectal cancers. CTNNB1 is altered in 2.9% of pancreatic adenocarcinomas. The CTNNB1 T41A mutation is known to be oncogenic. Preclinical studies suggest that CTNNB1 mutations may confer resistance to PI3K-AKT inhibitors in colorectal cancer. Cancers with CTNNB1 mutations are presumed to be resistant to pharmacologic inhibition of upstream components of the WNT pathway, instead requiring direct inhibition of b-catenin function. The role of CTNNB1 mutations in pancreatic adenocarcinomas requires further elucidation.

CTNNB1 encodes the protein b-catenin, a transcriptional activator involved in the WNT signaling pathway. Somatic gain-of-function mutations in CTNNB1 result in aberrant accumulation of the b-catenin protein and are prevalent in a wide range of solid tumors, including endometrial carcinoma, ovarian carcinoma, hepatocellular carcinoma, and colorectal carcinoma, among others. Cancers with CTNNB1 mutations are presumed to be resistant to pharmacologic inhibition of upstream components of the WNT pathway, instead requiring direct inhibition of b-catenin function. Genetic alterations in CTNNB1 have been identified in 4% of non-small cell lung cancers. The CTNNB1 S45F mutation is likely oncogenic. No real progress has been made in targeting oncogenic mutant forms of CTNNB1 in lung cancer.

The cytoplasmic b-catenin protein is implicated as a cell-cell adhesion regulator coupled with cadherin and is considered as a member in the wingless/Wnt signal transduction pathway. Mutations in CTNNB1, the gene encoding b-catenin, tend to impact or even eliminate APC-dependent serine and threonine phosphorylation sites in exon 3, resulting in oncogenic stabilization of the protein. Mutations in the b-catenin gene are uncommon in NSCLC occurring in about 1-4% of the cases. This particular variant has not been described lung adenocarcinomas but is located in a hotspot, thus likely to be oncogenic. Clinical correlation is recommended.

Beta catenin is a transcriptional co-regulator and an adapter protein for cellular adhesion; it comprises part of the Wnt signaling pathway and intracellular levels of beta-catenin are regulated by its phosphorylation, ubiquitination and proteosomal degradation. Accumulation of nuclear beta catenin can lead to a tumoral phenotype and oncogenic transformation in a variety of solid tumors. Various oncogenic mutants of beta catenin have been found in different tumor types which alter its degradation, leading to its accumulation and promoting tumor growth. Alterations in genes coding for members of the APC/b (beta)-catenin pathway have been identified in 20--25% of acinar cell carcinomas. These included inactivating mutations in APC as well as activating mutations in CTNNB1. CTNNB1 alterations have been identified in approximately 9% of pancreatic acinar cell carcinomas. CTNNB1 G34E is a rare mutation and does not lie within any known functional domains of the CTNNB1 protein. One study has shown that this mutation results in resistance to degradation, leading to increased pathway activation. Preclinical studies in CTNNB1 mutated solid tumors are underway. The full clinicopathological significance of CTNNB1 G34E remains to be further elucidated in pancreatic acinar cell carcinoma.

This gene is a known cancer gene.

This gene is a known cancer gene.