FBXW7 is a ubiquitin protein ligase subunit which regulates levels of NOTCH, cyclin E, and other proteins. Loss-of-function mutations of FBXW7 lead to constitutive Notch1 pathway activation via inhibition of ubiquitin-mediated degradation of activated NOTCH1 and MYC. Mutations of FBXW7 include missense and frameshift mutations. FBXW7 have been reported in approximately 4-30% of cases of T-ALL less than 5% of cases of B-ALL, less than 5% of cases of CLL and appear to be very rare/absent in acute myeloid leukemia. According to some, but not all studies, NOTCH1 pathway activation by NOTCH1 mutations or FBXW7 mutations in TALL have been associated with an improved prognosis (in cases without concomitant RAS or PTEN mutations) compared to cases without mutations in NOTCH1 or FBXW7. FBXW7 mutations may occur alone or together with mutations in NOTCH1 (typically those in the heterodimerization domain and more rarely those in the PEST domain of NOTCH1). FBXW7 mutations may result in resistance to gamma secretase inhibitors according to some experimental studies.

FBXW7 is a tumor suppressor gene that is mutated in several tumors including colorectal, liver, bladders and ovarian cancers. It is also mutated in endometrial and head and neck squamous cancers. Preclinical data suggest that FBXW7 mutations may sensitize cells to mTOR inhibitors.

FBXW7 is a tumor suppressor gene and is responsible for ubiquitination and turnover of several oncoprotiens. Loss-of-function mutations of FBXW7 lead to constitutive NOTCH1 pathway activation via inhibition of ubiquitin-mediated degradation of activated NOTCH1 and MYC. FBXW7 mutations have been reported in ~3-8% of melanomas. Preclinical data suggest that FBXW7 mutations sensitize cells to mTOR inhibitors. However, advanced tumors with somatic FBXW7 mutations and other concurrent molecular alterations might have limited therapeutic response to mTOR inihibitors. Correlation with other clinical and laboratory findings is recommended.

This gene is a known cancer gene.

This gene is a known cancer gene.

FBXW7 is a tumor suppressor gene responsible for the degradation of several proto-oncogenes. mTOR is one of the substrates of FBXW7-mediated protein degradation, and loss of function of FBXW7 increases the levels of total and activated mTOR. Codons 465 and 505 are some of the most frequently mutated sites in the FBXW7 gene. FBXW7 is mutated in approximately 15% of small bowel cancers. Preclinical data have suggested that inactivating mutations of FBXW7 could predict sensitivity to the mTOR inhibitor rapamycin; however, the clinical utility remains unknown.

FBXW7 is a tumor suppressor gene that is mutated in several tumors including colorectal, liver, bladders and ovarian cancers. It is also mutated in endometrial and head and neck squamous cancers. FBXW7 mutations are rare in pancreatic adenocarcinoma and are present in less than 1% of tumors. Preclinical data suggest that FBXW7 mutations may sensitize cells to mTOR inhibitors. The full pathologic significance of FBXW7 mutations in pancreatic adenocarcinoma remains to be more fully elucidated.

FBXW7 is a tumor suppressor gene responsible for the degradation of several proto-oncogenes. mTOR is one of the substrates of FBXW7-mediated protein degradation, and loss of function of FBXW7 increases the levels of total and activated mTOR. FBXW7 R505C lies within the WD4 repeat region and confers a loss of FBXW7-substrate interaction and impairs substrate degradation by FBXW7, resulting in sustained NICD and MYC expression. Preclinical data have suggested that inactivating mutations of FBXW7 could predict sensitivity to the mTOR inhibitor rapamycin; A single study has reported only limited activity in phase I trials using mTOR inhibitors in patients with advanced cancers including colorectal cancer. The clinical utility remains unknown.

FBXW7 is a tumor suppressor gene that is mutated in several tumors including colorectal, liver, bladder and ovarian cancers. It is also mutated in endometrial, esophageal, and head and neck squamous cancers. FBXW7 is a tumor suppressor gene responsible for the degradation of several proto-oncogenes. mTOR is one of the substrates of FBXW7-mediated protein degradation, and loss of function of FBXW7 increases the levels of total and activated mTOR. FBXW7 R505G lies within the WD repeat 4 of the FBXW7 protein. R505G has been identified in the scientific literature, but has not been biochemically characterized and therefore, its effect on FBXW7 protein function is unknown. Preclinical data suggest that FBXW7 mutations may sensitize cells to mTOR inhibitors, however, the response to mTOR inhibitors and the clinicopathologic effects of FBXW7 R505G remains to be further elucidated.

FBXW7 is a tumor suppressor gene responsible for the degradation of several proto-oncogenes. mTOR is one of the substrates of FBXW7-mediated protein degradation, and loss of function of FBXW7 increases the levels of total and activated mTOR. Due to the disruption of the WD repeat domain, the FBXW7 R393* truncating mutation is predicted to lead to a loss of FBXW7 protein function. Preclinical data have suggested that inactivating mutations of FBXW7 could predict sensitivity to the mTOR inhibitor rapamycin; however, the clinical utility remains unknown. A single study has reported only limited activity in phase I trials using mTOR inhibitors in patient with advanced cancers including colorectal cancer.

FBXW7 is a tumor suppressor gene responsible for the degradation of several proto-oncogenes, and is mutated in several tumors including colorectal, liver, bladders and ovarian cancers. mTOR is one of the substrates of FBXW7-mediated protein degradation, and loss of function of FBXW7 increases the levels of total and activated mTOR. FBXW7 loss of function mutations have been described in many types of adenocarcinoma including colon, bladder and lung. FBXW7 mutations are present in approximately 7% of urothelial carcinomas. Preclinical data have suggested that inactivating mutations of FBXW7 could predict sensitivity to the mTOR inhibitor rapamycin. However, this particular variant (H500Y) has not been characterized in the scientific literature. Therefore, the effect on protein function is unknown. Clinical correlation is recommended.

FBXW7 is a tumor suppressor gene responsible for the degradation of several proto-oncogenes. mTOR is one of the substrates of FBXW7-mediated protein degradation, and loss of function of FBXW7 increases the levels of total and activated mTOR. FBXW7 R505C lies within the WD4 repeat region and confers a loss of FBXW7-substrate interaction and impairs substrate degradation by FBXW7, resulting in sustained NICD and MYC expression. Preclinical data have suggested that inactivating mutations of FBXW7 could predict sensitivity to the mTOR inhibitor rapamycin. A single study has reported only limited activity in phase I trials using mTOR inhibitors in patients with advanced cancers including colorectal cancer. The clinical utility remains unknown.

FBXW7 is a tumor suppressor gene responsible for the degradation of several proto-oncogenes and is inactivated by mutation in various cancers, most frequently in endometrial and colorectal cancers. Substrates of FBXW7 include the proteins c-MYC, mTOR, NOTCH1, cyclin-E, and JUN, which are instrumental in the regulation of cell division, differentiation and growth, and which are often inappropriately activated in cancer. Inactivation of FBXW7 by mutation or copy number loss results in aberrant accumulation of the above oncoproteins, which subsequently contributes to malignant transformation. mTOR is one of the substrates of FBXW7-mediated protein degradation, and loss of function of FBXW7 increases the levels of total and activated mTOR. Most mutations in FBXW7 are point mutations that disrupt substrate binding, while <10% are small deletions or insertions. FBXW7 is altered in 17% of colorectal adenocarcinomas. The FBXW7 R465H variant is considered to be likely oncogenic. Preclinical data have suggested that inactivating mutations of FBXW7 could predict sensitivity to the mTOR inhibitor rapamycin. A single study has reported only limited activity in phase I trials using mTOR inhibitors in patients with advanced cancers including colorectal cancer. The clinical utility remains unknown.