Currently, as the largest family of E3 ubiquitin ligases, Skp1-Cullin 1-F-box (SCF) E3 ligase complexes have attracted extensive attention. Among SCF complexes, Skp2, β-TrCP, and FBXW7 have undergone extensive research on their structures and functions. Previous studies suggest Skp2, β-TrCP, and FBXW7 are overexpressed in numerous cancers. Thus, the SCF E3 ligase complex has become a significant target for the development of anti-cancer drugs. Over the past few decades, a variety of anti-tumor inhibitors targeting the SCF E3 ligase complex have been attempted. However, since almost none of the SCF E3 ligase inhibitors passed clinical trials, the design and synthesis of the new inhibitors are needed. Here, we will introduce the structure and function of Skp2, β-TrCP, and FBXW7, their connections with cancer development, the relevant in vitro and in vivo activities, selectivity, structure-activity relationships, and the therapeutic or preventive application of small molecule inhibitors targeting these three F-box proteins reported in the patent (2010-present). This information will help develop drugs targeting the SCF E3 ubiquitin ligase, providing new strategies for future cancer treatments.

Primary vaginal carcinosarcoma (VCS) is an extremely rare and aggressive tumor consisting of admixed malignant epithelial and mesenchymal elements. We report a case of VCS that was subjected to analysis by immunohistochemistry and next-generation sequencing (NGS). A 53-year-old woman with post-menopausal vaginal bleeding underwent surgical excision followed by concurrent chemoradiation. A well demarcated tumor was growing in a discontinuous fashion at a location some distance from both the cervix and vulva. Microscopically, the tumor consisted of adenocarcinoma components and sarcoma components consisting of a sheet-like growth of spindle-shaped cells, and we diagnosed this tumor as primary vaginal carcinosarcoma. NGS analysis of each component identified the following variants, TP53, PIK3CA, KRAS and FBXW7. A comparison of microsatellite instability (MSI) and tumor mutation burden (TMB) showed that within both tissues the sarcomatous components had a higher MSI and TMB than the carcinomatous components. This case supports \"a monoclonal theory\" with the genome profile being similar to other malignant mixed Müllerian tumors.

BACKGROUND: Various studies investigating the clinical significance of FBXW7 mutation and/or expression have yielded inconclusive results in colorectal cancer (CRC) patients. Therefore, the present meta-analysis summarizes previous evidence and evaluates the clinical significance, including the prognostic role, of FBXW7 status in CRCs.
METHODS: The meta-analysis was conducted by searching the databases of PubMed, China National Knowledge Infrastructure (CNKI), WANFANG data, Web of Science, Embase, and Web of Science. Pooled odds ratios (ORs) and hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) were calculated to assess the relationships between FBXW7 status and clinicopathological features and survival in CRC, respectively.
RESULTS: Ten studies involving 4199 patients met the inclusion criteria and included in our meta-analysis. FBXW7 mutation/low expression was obviously correlated with advanced T stage (OR = 0.44, 95% CI: 0.27-0.74, P <  0.01) and lymph node metastasis (OR = 1.88, 95% CI: 1.40-2.53, P <  0.01), but was not associated with other parameters. Further investigation found that FBXW7 mutation/low expression predicted poor OS (HR = 1.25, 95% CI: 1.06-1.47, P <  0.01), but not DFS in CRC (HR = 1.04, 95% CI: 0.60-1.82, P = 0.88). Subgroup analysis found that FBXW7 status was obviously correlated with OS in cohorts recruited after 2009 (HR = 1.32, 95% CI: 1.17-1.50, P <  0.01), from eastern Asia (HR = 1.27, 95% CI: 1.04-1.55, P = 0.02), detected by immunohistochemistry/qRT-PCR (HR = 1.39, 95% CI: 1.22-1.59, P <  0.01), and analysed with multivariate method (HR = 1.47, 95% CI: 1.25-1.74, P <  0.01).
CONCLUSIONS: This study indicates that FBXW7 status, expression level especially, is associated with OS but not DFS in CRC. FBXW7 expression level may function as a prognostic biomarker in CRC.

Metastatic unresectable malignant melanoma (MM) owing to its intrinsic biological invasion potential and low sensitivity to radiochemotherapy has a poor prognosis and a high rate of mortality; the mean survival period is only 6-8 months, and the 5-year survival rate is less than 10%. The progression of patients with brain and liver metastases is worse than those with other distant or visceral metastases. With the advent of immunotherapy, especially immune-checkpoint inhibitors, long-term remission of stage IV disease may be achieved in some patients. Despite recent advances, not all patients benefit or can afford immunotherapy. Here, we report the case of a 44-year-old man whose initial diagnosis was MM with liver and multiple brain metastases. A high expression of F-box/WD repeat-containing protein 7 (FBXW7) inactivating mutation was observed, and the patient was treated with a combination of everolimus and temozolomide (TMZ) following palliative radiotherapy. The patient was stable for approximately 17 months, and eventually showed an overall survival (OS) of about 19 months. This case is novel and instructional, which highlights that the combination of everolimus and TMZ might be effective, with manageable toxicity, for advanced MM patients with FBXW7 mutation. And it may provide a reference for the treatment of analogous patients.

BACKGROUND: MicroRNAs (miRNAs) are a class of small, well-conserved, non-coding RNAs that regulate the translation of RNAs. They have a role in biological and pathological process including cell differentiation, apoptosis, proliferation and metabolism. Since their discovery, they have been shown to have a potential role in cancer pathogenesis through their function as oncogenes or tumor suppressors. A substantial number of miRNAs show differential expression in esophageal cancer tissues, and so have been investigated for possible use in diagnosis. Furthermore, there is increasing interest in their use as prognostic markers and determining treatment response, as well as identifying their downstream targets and understanding their mode of action.
METHODS: We analyzed the most recent studies on miRNAs in esophageal cancer and/or Barrett\'s esophagus (BE). The publications were identified by searching in PuBMed for the following terms: Barrett\'s esophagus and microRNA; esophageal cancer and microRNA.
RESULTS: Four miRNAs (mi-R-25, -99a, -133a and -133b) showed good potential as diagnostic markers and interestingly five (mi-R-21, -27b, -126, - 143 and -145) appeared to be useful both as diagnostic and prognostic/predictive markers.
CONCLUSIONS: The data so far on miRNAs in esophageal carcinogenesis is promising but further work is required to determine whether miRNAs can be used as biomarkers, not only in the clinical setting or added to individualized treatment regimes but also in non-invasive test by making use of miRNAs identified in blood.