Overexpressed transcription factor FOXM1 contributes to the progression of colorectal cancer

Evaluation of Forkhead BOX M1 (FOXM1) gene expression in colorectal cancer

Forkhead Box M1 (FOXM1)-a key cell cycle regulator is a member of the Forkhead transcription factor family. It plays a key role in embryogenesis and cell proliferation and has been strongly linked to various solid tumors. We sought to understand the regulation of FOXM1 in colorectal cancer (CRC), as well as if and to what extent other clinicopathological characteristics are associated with FOXM1. The investigation comprised 98 CRC samples and normal tissues (controls). All colon cancer patients had a colonoscopy and targeted biopsy. All rectal cancer patients had a CT and MRI. Real-time PCR, Immunohistochemistry, and Western blotting were used to evaluate FOXM1 expression, and the findings were analyzed using SPSS (v.26). FOXM1 mRNA and protein expression were substantially upregulated in tumor tissues, with the majority of these proteins localized in nucleo-cytoplasm. Elevated protein levels of FOXM1 were strongly correlated with lower education level, larger tumor size, lymph node status, lymphovascular invasion (LVI), perineural invasion (PNI), lymph node metastasis (LNM), tumor invasion depth (subserosal and serosal invasion), late stage (III and IV), localization (nucleo-cytoplasmic), intensity (strong) and recurrence. Based on survival analysis, FOXM1 overexpression and nucleo-cytoplasmic localization were associated with shorter disease-free survival while stage and PNI were linked to poorer overall and disease-free survival. According to the results of the Cox regression analysis, stage and PNI were significant predictors of prognosis in CRC patients. FOXM1 expression was elevated in CRC and was linked to reduced disease-free survival. These findings support prior reports and hence FOXM1 can be an important prognostic marker for CRC and a promising therapeutic target. Additionally, we found a link between poor disease-free survival and FOXM1's nucleo-cytoplasmic localization. However, since the sample size of this study was small, further research is needed to validate our findings.

FOXM1, MEK, and CDK4/6: New Targets for Malignant Peripheral Nerve Sheath Tumor Therapy

Malignant peripheral nerve sheath tumors (MPNSTs) are deadly sarcomas, which desperately need effective therapies. Half of all MPNSTs arise in patients with neurofibromatosis type I (NF1), a common inherited disease. NF1 patients can develop benign lesions called plexiform neurofibromas (PNFs), often in adolescence, and over time, some PNFs, but not all, will transform into MPNSTs. A deeper understanding of the molecular and genetic alterations driving PNF-MPNST transformation will guide development of more targeted and effective treatments for these patients. This review focuses on an oncogenic transcription factor, FOXM1, which is a powerful oncogene in other cancers but little studied in MPNSTs. Elevated expression of FOXM1 was seen in patient MPNSTs and correlated with poor survival, but otherwise, its role in the disease is unknown. We discuss what is known about FOXM1 in MPNSTs relative to other cancers and how FOXM1 may be regulated by and/or regulate the most commonly altered players in MPNSTs, particularly in the MEK and CDK4/6 kinase pathways. We conclude by considering FOXM1, MEK, and CDK4/6 as new, clinically relevant targets for MPNST therapy.

WNT5A: a double-edged sword in colorectal cancer progression

The Wnt signaling pathway is known to play a crucial role in cancer, and WNT5A is a member of this pathway that binds to the Frizzled (FZD) and Receptor Tyrosine Kinase-Like Orphan Receptor (ROR) family members to activate non-canonical Wnt signaling pathways. The WNT5A pathway is involved in various cellular processes, such as proliferation, differentiation, migration, adhesion, and polarization. In the case of colorectal cancer (CRC), abnormal activation or inhibition of WNT5A signaling can lead to both oncogenic and antitumor effects. Moreover, WNT5A is associated with inflammation, metastasis, and altered metabolism in cancer cells. This article aims to discuss the molecular mechanisms and dual roles of WNT5A in CRC.

Urushiol V Suppresses Cell Proliferation and Enhances Antitumor Activity of 5-FU in Human Colon Cancer Cells by Downregulating FoxM1

Colorectal cancer (CRC) is one of the most common malignant tumor. 5-FU is commonly used for the treatment of CRC. However, the development of drug resistance in tumor chemotherapy can seriously reduce therapeutic efficacy of 5-FU. Recent data show that FoxM1 is associated with 5-FU resistance in CRC. FoxM1 plays a critical role in the carcinogenesis and drug resistance of several malignancies. It has been reported that urushiol V isolated from the cortex of Rhus verniciflua Stokes is cytotoxic to several types of cancer cells. However, the underlying molecular mechanisms for its antitumor activity and its potential to attenuate the chemotherapeutic resistance in CRC cells remain unknown. Here, we found that urushiol V could inhibit the cell proliferation and induced S-phase arrest of SW480 colon cancer cells. It inhibited protein expression level of FoxM1 through activation of AMPK. We also investigated the combined effect of urushiol V and 5-FU. The combination treatment reduced FoxM1 expression and consequently reduced cell growth and colony formation in 5-FU resistant colon cancer cells (SW480/5-FUR). Taken together, these result suggest that urushiol V from Rhus verniciflua Stokes can suppress cell proliferation by inhibiting FoxM1 and enhance the antitumor capacity of 5-FU. Therefore, urushiol V may be a potential bioactive compound for CRC therapy.

Downregulation of lncRNA PVT1 inhibits proliferation and migration of mesothelioma cells by targeting FOXM1

Malignant mesothelioma is a highly aggressive tumor, and an effective strategy for its treatment is not yet available. Long non-coding RNAs (lncRNAs) have been reported to be associated with various biological processes, including the regulation of gene expression of cancer-related pathways. Among various lncRNAs, plasmacytoma variant translocation 1 (PVT1) acts as a tumor promoter in several human cancers, but its mechanism of action has not yet been elucidated. Increased PVT1 expression was identified in ACC-MESO-1, ACC-MESO-4, CRL-5915, and CRL-5946 mesothelioma cell lines. PVT1 expression was investigated in mesothelioma cell lines by reverse transcription-quantitative polymerase chain reaction and its functional analysis by cell proliferation, cell cycle, cell migration, and cell invasion assays, as well as western blot analysis of downstream target genes. Knockdown of PVT1 expression in these cell lines by small interfering RNA transfection resulted in decreased cell proliferation and migration and increased the proportion of cells in the G2/M phase. The results of reverse transcription-quantitative polymerase chain reaction analysis revealed that PVT1 knockdown in mesothelioma cell lines caused the downregulation of Forkhead box M1 (FOXM1) expression, while the results of western blot analysis revealed that this knockdown reduced FOXM1 expression at the protein level. In addition, combined knockdown of PVT1 and FOXM1 decreased the proliferation of mesothelioma cell lines. In conclusion, PVT1 and FOXM1 were involved in the proliferation of cancer cells. Therefore, PVT1-FOXM1 pathways may be considered as candidate targets for the treatment of malignant mesothelioma.

Antitumor Effects of Paeoniflorin on Hippo Signaling Pathway in Gastric Cancer Cells

Background

Paeoniflorin has been reported to exert antitumor effects on human cancers. However, the role of paeoniflorin in gastric cancer and the underlying molecular mechanism are unelucidated. Therefore, we determined whether paeoniflorin could exhibit anticancer activity in gastric cancer cells.

Methods

MTT was used to measure the viability of cells after paeoniflorin treatment. FACS was performed to examine cell apoptosis. Wound healing and transwell invasion assays were conducted to examine cell migratory and invasive activities. Western blotting was used to explore the mechanism by which paeoniflorin exerted tumor suppressive effects.

Results

We found that paeoniflorin suppressed cell growth, enhanced apoptosis, and reduced cell invasion. Notably, we showed that paeoniflorin inhibited the expression of TAZ in gastric cancer cells. The overexpression of TAZ abrogated the antitumor activity of paeoniflorin in gastric cancer cells. In contrast, the downregulation of TAZ promoted the tumor suppressive effects of paeoniflorin treatment.

Conclusion

Hence, targeting TAZ with paeoniflorin could be a novel approach for the treatment of human gastric cancer.

SETD1A Promotes Proliferation of Castration-Resistant Prostate Cancer Cells via FOXM1 Transcription

Androgen deprivation therapy eventually leads to the development of castration-resistant prostate cancer (CRPC). Here, we demonstrate for the first time that the histone H3K4 methyltransferase SETD1A is a major regulator for the proliferation of metastatic CRPC (mCRPC). The expression of SETD1A was significantly correlated with the survival rate of patients with prostate cancer. SETD1A, which is expressed at a higher level in mCRPC than in primary prostate cancer cells, promotes the expression of FOXM1, a gene encoding a cell proliferation-specific transcription factor. SETD1A is recruited to the promoter region of FOXM1 (forkhead box M1) upon binding to E2F1, a protein that regulates the transcription of FOXM1 and contributes to the trimethylation of H3K4 in the FOXM1 promoter region. In addition, SETD1A is essential for the expression of stem cell factor (e.g., OCT4, octamer-binding transcription factor 4) and stem cell formation in mCRPC, suggesting the importance of SETD1A expression in mCRPC tumor formation. Notably, poor prognosis is associated with high expression of the SETD1A-FOXM1 pair in clinical data sets. Therefore, our study suggests that SETD1A plays an important role in the proliferation of mCRPC by regulating FOXM1 transcription.

FOXM1: a potential therapeutic target in human solid cancers

Introduction: FOXM1 is one of the most frequently overexpressed proteins in human solid cancers. Here, we discuss novel direct targets of FOXM1 as well as new pathways involving FOXM1, through which this protein exerts its oncogenic activity.Areas covered: We give a detailed review of FOXM1 transcriptional targets involved in 16 different types of human cancer as published in the literature in the last 5 years. We also discuss a novel positive feedback loop between FOXM1 and AKT - both well-established master regulators of cancer.Expert opinion: Despite the discovery of several FOXM1 inhibitors over the years (by our team and others), their therapeutic use is limited by their adverse off-target effects.Newly-discovered proteins regulated by FOXM1 present a promising alternative approach to target its pro-cancer activity. In addition, targeting regulating proteins that take part in the positive feedback loop between FOXM1/AKT has the double advantage of suppressing both, and can lead to developing novel anti-cancer drugs.

The forkhead-box family of transcription factors: key molecular players in colorectal cancer pathogenesis

Colorectal cancer (CRC) is the third most commonly occurring cancer worldwide and the fourth most frequent cause of death having an oncological origin. It has been found that transcription factors (TF) dysregulation, leading to the significant expression modifications of genes, is a widely distributed phenomenon regarding human malignant neoplasias. These changes are key determinants regarding tumour’s behaviour as they contribute to cell differentiation/proliferation, migration and metastasis, as well as resistance to chemotherapeutic agents. The forkhead box (FOX) transcription factor family consists of an evolutionarily conserved group of transcriptional regulators engaged in numerous functions during development and adult life. Their dysfunction has been associated with human diseases. Several FOX gene subgroup transcriptional disturbances, affecting numerous complex molecular cascades, have been linked to a wide range of cancer types highlighting their potential usefulness as molecular biomarkers. At least 14 FOX subgroups have been related to CRC pathogenesis, thereby underlining their role for diagnosis, prognosis and treatment purposes.

This manuscript aims to provide, for the first time, a comprehensive review of FOX genes’ roles during CRC pathogenesis. The molecular and functional characteristics of most relevant FOX molecules (FOXO, FOXM1, FOXP3) have been described within the context of CRC biology, including their usefulness regarding diagnosis and prognosis. Potential CRC therapeutics (including genome-editing approaches) involving FOX regulation have also been included. Taken together, the information provided here should enable a better understanding of FOX genes’ function in CRC pathogenesis for basic science researchers and clinicians.

Regulation of the master regulator FOXM1 in cancer

FOXM1 (forkhead box protein M1) is a critical proliferation-associated transcription factor that is widely spatiotemporally expressed during the cell cycle. It is closely involved with the processes of cell proliferation, self-renewal, and tumorigenesis. In most human cancers, FOXM1 is overexpressed, and this indicates a poor prognosis for cancer patients. FOXM1 maintains cancer hallmarks by regulating the expression of target genes at the transcriptional level. Due to its potential role as molecular target in cancer therapy, FOXM1 was named the Molecule of the Year in 2010. However, the mechanism of FOXM1 dysregulation remains indistinct. A comprehensive understanding of FOXM1 regulation will provide novel insight for cancer and other diseases in which FOXM1 plays a major role. Here, we summarize the transcriptional regulation, post-transcriptional regulation and post-translational modifications of FOXM1, which will provide extremely important implications for novel strategies targeting FOXM1.

Paeoniflorin inhibits cell growth and induces cell cycle arrest through inhibition of FoxM1 in colorectal cancer cells

Paeoniflorin (PF) exhibits tumor suppressive functions in a variety of human cancers. However, the function of PF and molecular mechanism in colorectal cancer are elusive. In the present study, we investigated whether PF could exert its antiproliferative activity, anti-migration, and anti-invasive function in colorectal cancer cells. We found that PF inhibited cell growth and induced apoptosis and blocked cell cycle progression in the G0/G1 phase in colorectal cancer cells. Moreover, we found that PF suppressed cell migration and invasion in colorectal cancer cells. FoxM1 has been reported to play an important oncogenic role in human cancers. We also determine whether PF inhibited the expression of FoxM1, leading to its anti-cancer activity. We found that PF treatment in colorectal cancer cells resulted in down-regulation of FoxM1. The rescue experiments showed that overexpression of FoxM1 abrogated the tumor suppressive function induced by PF treatment. Notably, depletion of FoxM1 promoted the anti-tumor activity of PF in colorectal cancer cells. Therefore, inhibition of FoxM1 could participate in the anti-tumor activity of PF in colorectal cancer cells.

The addition of celecoxib improves the antitumor effect of cetuximab in colorectal cancer: role of EGFR-RAS-FOXM1-β- catenin signaling axis

Here we showed that the addition of the COX-2 inhibitor celecoxib improved the antitumor efficacy in colorectal cancer (CRC) of the monoclonal anti-EGFR antibody cetuximab. The addition of celecoxib augmented the efficacy of cetuximab to inhibit cell proliferation and to induce apoptosis in CRC cells. Moreover, the combination of celecoxib and cetuximab was more effective than either treatment alone in reducing the tumor volume in a mouse xenograft model. The combined treatment enhanced the inhibition of EGFR signaling and altered the subcellular distribution of β-catenin. Moreover, knockdown of FOXM1 showed that this transcription factor participates in this enhanced antitumoral response. Besides, the combined treatment decreased β-catenin/FOXM1 interaction and reduced the cancer stem cell subpopulation in CRC cells, as indicated their diminished capacity to form colonospheres. Notably, the inmunodetection of FOXM1 in the nuclei of tumor cells in human colorectal adenocarcinomas was significantly associated with response of patients to cetuximab. In summary, our study shows that the addition of celecoxib enhances the antitumor efficacy of cetuximab in CRC due to impairment of EGFR-RAS-FOXM1-β-catenin signaling axis. Results also support that FOXM1 could be a predictive marker of response of mCRC patients to cetuximab therapy.

MicroRNA-761 promotes the sensitivity of colorectal cancer cells to 5-Fluorouracil through targeting FOXM1

Resistance to chemotherapy is a big challenge for treatment of patients with colorectal cancer; however; the mechanism underlying chemoresistance in colorectal cancer cell has not been elucidated. MicroRNAs (miRNAs) are new players in the development of drug chemoresistance. In our study, we indicated that overexpression of miR-761 promoted the sensitivity of colorectal cancer cells to 5-Fluorouracil (5-FU). miR-761 expression was downregulated in colorectal cancer cell lines and tissues. miR-761 expression was lower in patients with low grade than in patients with high grade. In additon, we showed that elevated expression of miR-761 suppressed colorectal cancer cell proliferation, cell cycle, colony formation and cell invasion. We identified that FOXM1 was a direct target gene of miR-761 in colorectal cancer cell. FOXM1 expression was upregulated in colorectal cancer tissues compare to the adjacent non-tumor tissues. MiR-761 expression was negatively associated with the expression of FOXM1 in colorectal cancer tissues. Elevated expression of FOXM1 suppressed the sensitivity of miR-761-overexpressing HT29 cells to 5-FU. We also indicated that FOXM1 overexpression promoted cell proliferation, cycle and invasion of miR-761-overexpressing HT29 cells. These data suggested that miR-761 played a tumor suppressor miRNA in colorectal cancer progression and reduced miR-761 expression might be a major mechanism for 5-FU resistance in colorectal cancer cell.

Aberrant activation of hedgehog signaling promotes cell proliferation via the transcriptional activation of forkhead Box M1 in colorectal cancer cells

BACKGROUND

Recent evidence suggests that the aberrant activation of Hedgehog (Hh) signaling by Gli transcription factors is characteristic of a variety of aggressive human carcinomas, including colorectal cancer (CRC). Forkhead box M1 (FoxM1) controls the expression of a number of cell cycle regulatory proteins, and FoxM1 expression is elevated in a broad range of human malignancies, which suggests that it plays a crucial role in tumorigenesis. However, the mechanisms underlying FoxM1 expression are not fully understood. Here, we aim to further investigate the molecular mechanism by which Gli1 regulates FoxM1 in CRC.

METHODS

Western blotting and immunohistochemistry (IHC) were used to evaluate FoxM1 and Gli1 protein expression, respectively, in CRC tissues and matched adjacent normal mucosa. BrdU (5-bromo-2'-deoxyuridine) and clone formation assays were used to clarify the influence of FoxM1 on CRC cell growth and proliferation. Chromatin immunoprecipitation (ChIP) and luciferase experiments were performed to explore the potential mechanisms by which Gli1 regulates FoxM1. Additionally, the protein and mRNA expression levels of Gli1 and FoxM1 in six CRC cell lines were measured using Western blotting and real-time PCR. Finally, the effect of Hh signaling on the expression of FoxM1 was studied in cell biology experiments, and the effects of Hh signaling activation and FoxM1 inhibition on the distribution of CRC cells among cell cycle phases was assessed by flow cytometry.

RESULTS

Gli1 and FoxM1 were abnormally elevated in human CRC tissues compared with matched adjacent normal mucosa samples, and FoxM1 is a downstream target gene of the transcription factor Gli1 in CRC and promoted CRC cell growth and proliferation. Moreover, the aberrant activation of Hh signaling promoted CRC cell proliferation by directly binding to the promoter of FoxM1 and transactivating the activity of FoxM1 in CRC cells.

CONCLUSION

The dysregulation of the Hh-Gli1-FoxM1 axis is essential for the proliferation and growth of human CRC cells and offers a potent target for therapeutic intervention in CRC.

Genomic copy number variation associated with clinical outcome in canine cutaneous mast cell tumors

Mast cell tumors are the most common malignant cutaneous tumors in dogs. Although there are several prognostic factors involved, the clinical and biological behavior of this type of tumor varies greatly, making the best choice of treatment challenging. Molecular techniques can be used to evaluate a large number of genes involved in the neoplastic process and aid in the selection of candidate genes related to prognostic and predicting factors. Identification of the genes associated with tumor development and progression can be performed through the analysis of numerical and structural changes in DNA isolated from tumor cells by array comparative genomic hybridization (aCGH). The aim of this study was to compare copy number variations (CNVs) in cutaneous mast cell tumors of dogs that survived less than six (ST<6) and >12months (ST>12) from the date of diagnosis. Ten animals were used: four from Group ST>12 and six from Group ST<6. Genomic DNA was extracted, and aCGH was performed using Agilent Canine Genome CGH Microarray 4×180 (ID-252 552 - Agilent, USA). Data analysis was carried out using Nexus program version 5.0 (Biodiscovery, USA). The group ST>12 presented 11±3.3 CNVs, while the ST<6 group presented 85±38.5 CNVs. Regions of loss in PTEN and FAS as well as regions of gains in MAPK3, WNT5B, FGF, FOXM1 and RAD51 were detected in mast cell tumors with shorter survival times, and thus, worst prognoses, allowing for the identification of potential candidate genes for more detailed studies.