FOXF2 Regulates PRUNE2 Transcription in the Pathogenesis of Colorectal Cancer

FOXF2 suppressed esophageal squamous cell carcinoma by reducing M2 TAMs via modulating RNF144A-FTO axis

Esophageal squamous cell carcinoma (ESCC) is one of the deadliest cancers because of its high invasiveness and low survival. Tumor-associated macrophages (TAMs) are closely associated with the tumor cell proliferation, metastasis and immunosuppression. As a member of the FOX family, forkhead box F2 (FOXF2) was down-regulated in ESCC. However, its role in ESCC and TAMs, as well as the underlying mechanism, remains unclear. We found that differentially expressed genes (DEGs) in ESCC were enriched in proliferation, migration, macrophage and cancer pathways. Among these DEGs, FOXF2 caught our eyes. FOXF2 was down-regulated in ESCC. Overexpression FOXF2 inhibited the proliferation of ESCC cells and the M2 polarization of TAMs, but silenced FOXF2 reversed these results. Notably, FOXF2 promoted the transcription of ring finger protein 144A (RNF144A), which is an E3 ubiquitin ligase, causing the ubiquitination and degradation of FTO Alpha-Ketoglutarate Dependent Dioxygenase (FTO), an N6-methyladenosine (m6A) demethylase. Furthermore, overexpression of FTO abolished the effects of FOXF2 on TAM polarization. In conclusion, FOXF2 alleviates ESCC via promoting the transcription of RNF144A which results in the ubiquitylation and degradation of FTO. Targeting FOXF2/RNF144A/FOT axis might be a possible strategy for the treatment of ESCC.

Transcription factor FOXF2 promotes the development and progression of pancreatic cancer by targeting MSI2

Pancreatic cancer (PC) is a malignant tumor possessing high mortality. The role of transcription factor Forkhead Box F2 (FOXF2) in PC remains unverified. The current study investigated the roles of FOXF2 in developing PC in vitro and in vivo. A xenograft tumor model was constructed with nude mice injected using FOXF2‑overexpressing PC cells or FOXF2‑silenced PC cells. High FOXF2 expression significantly enhanced the proliferation ability of PC cells in vitro and pancreatic tumor growth in vivo. The cell cycle analysis indicated that transition of G1‑S phase was promoted by FOXF2. The cell cycle‑associated proteins cyclin D1, CDK2, phosphorylated (p)‑CDK2 and p‑RB were upregulated in the FOXF2‑overexpressing cells and downregulated in the cells with FOXF2 knockdown. Flow cytometric analysis and Hoechst staining showed that the percentage of apoptotic cells was significantly increased after FOXF2 was silenced. FOXF2 knockdown promoted expression of pro‑apoptotic proteins (Bad, Bax and cleaved caspase‑3) while suppressing the anti‑apoptotic proteins (Bcl‑2 and Bcl‑xl) at the protein level. FOXF2 improved the migration and invasion of PC cells in vitro. Moreover, luciferase and chromatin immunoprecipitation assays revealed that FOXF2 binds to the MSI2 promoter, promoting its transcriptional expression. FOXF2 knockdown inhibited the MSI2 protein translation while enhancing the translation of NUMB protein, suppressing PC development in vivo. MSI2 silencing reversed the promotive effect mediated by FOXF2 on cell proliferation. These results demonstrated that FOXF2 is essential in PC progression, and the potential mechanism includes regulating MSI2 transcription.

Analyzing aberrant DNA methylation in colorectal cancer uncovered intangible heterogeneity of gene effects in the survival time of patients

Colorectal cancer (CRC) involves epigenetic alterations. Irregular gene-methylation alteration causes and advances CRC tumor growth. Detecting differentially methylated genes (DMGs) in CRC and patient survival time paves the way to early cancer detection and prognosis. However, CRC data including survival times are heterogeneous. Almost all studies tend to ignore the heterogeneity of DMG effects on survival. To this end, we utilized a sparse estimation method in the finite mixture of accelerated failure time (AFT) regression models to capture such heterogeneity. We analyzed a dataset of CRC and normal colon tissues and identified 3406 DMGs. Analysis of overlapped DMGs with several Gene Expression Omnibus datasets led to 917 hypo- and 654 hyper-methylated DMGs. CRC pathways were revealed via gene ontology enrichment. Hub genes were selected based on Protein-Protein-Interaction network including SEMA7A, GATA4, LHX2, SOST, and CTLA4, regulating the Wnt signaling pathway. The relationship between identified DMGs/hub genes and patient survival time uncovered a two-component mixture of AFT regression model. The genes NMNAT2, ZFP42, NPAS2, MYLK3, NUDT13, KIRREL3, and FKBP6 and hub genes SOST, NFATC1, and TLE4 were associated with survival time in the most aggressive form of the disease that can serve as potential diagnostic targets for early CRC detection.

PI3K/AKT/mTOR Dysregulation and Reprogramming Metabolic Pathways in Renal Cancer: Crosstalk with the VHL/HIF Axis

Renal cell carcinoma (RCC) represents 85-95% of kidney cancers and is the most frequent type of renal cancer in adult patients. It accounts for 3% of all cancer cases and is in 7th place among the most frequent histological types of cancer. Clear cell renal cell carcinoma (ccRCC), accounts for 75% of RCCs and has the most kidney cancer-related deaths. One-third of the patients with ccRCC develop metastases. Renal cancer presents cellular alterations in sugars, lipids, amino acids, and nucleic acid metabolism. RCC is characterized by several metabolic dysregulations including oxygen sensing (VHL/HIF pathway), glucose transporters (GLUT 1 and GLUT 4) energy sensing, and energy nutrient sensing cascade. Metabolic reprogramming represents an important characteristic of the cancer cells to survive in nutrient and oxygen-deprived environments, to proliferate and metastasize in different body sites. The phosphoinositide 3-kinase-AKT-mammalian target of the rapamycin (PI3K/AKT/mTOR) signaling pathway is usually dysregulated in various cancer types including renal cancer. This molecular pathway is frequently correlated with tumor growth and survival. The main aim of this review is to present renal cancer types, dysregulation of PI3K/AKT/mTOR signaling pathway members, crosstalk with VHL/HIF axis, and carbohydrates, lipids, and amino acid alterations.