FOXP1 regulation via the PI3K/Akt/p70S6K signaling pathway in breast cancer cells

HTRA3 transcriptionally inhibited by FOXP1 suppresses tumorigenesis of osteosarcoma via the PTEN/PI3K/AKT pathway

Despite recent advances in understanding the biological behavior of osteosarcoma (OS), OS is still the most common primary bone sarcoma that endangers the health of children and adolescents. High-temperature requirement A (HTRA) protease family plays an important regulatory role in numerous malignancies and acts as a prognostic biomarker. However, the function and underlying mechanisms of the HTRA family in OS development remain unknown. Through analyzing the GSE126209 dataset obtained from different Gene Expression Omnibus (GEO) databases, we found that HTRA3 as a member of the HTRA family was downregulated in OS tissues compared with that in normal tissues. Functional experiments indicated that HTRA3 overexpression suppressed malignant behaviors of OS cells in vitro and tumor growth in vivo. Mechanistically, we found that HTRA3 co-localized with the X-linked inhibitor of apoptosis protein (XIAP) and decreased XIAP stability. Further investigation showed that XIAP knockdown inhibited the degradation of phosphatase and tensin homolog (PTEN) and that HTRA3 caused the blockage of PTEN/phosphoinositide 3-kinase (PI3K)/AKT pathway, characterized as the reverse of cell function caused by HTRA3 overexpression after PTEN inhibitor BpV (HOpic) treatment. Detailed investigations showed that forkhead box protein 1 (FOXP1), an oncogene in OS progression, downregulated HTRA3 expression and inhibited the transcriptional activity of HTRA3, suggesting that HTRA3 was regulated negatively by FOXP1. In conclusion, our study demonstrates that HTRA3 is a repressor involved in OS development via the PTEN/PI3K/AKT pathway under the modulation of transcription factor FOXP1, and it may provide a therapeutic direction for OS patients.

Abrogating Metastatic Properties of Triple-Negative Breast Cancer Cells by EGFR and PI3K Dual Inhibitors

Triple-negative breast cancer (TNBC) is a devastating BC subtype. Its aggressiveness, allied to the lack of well-defined molecular targets, usually culminates in the appearance of metastases that account for poor prognosis, particularly when they develop in the brain. Nevertheless, TNBC has been associated with epidermal growth factor receptor (EGFR) overexpression, leading to downstream phosphoinositide 3-kinase (PI3K) signaling activation. We aimed to unravel novel drug candidates for TNBC treatment based on EGFR and/or PI3K inhibition. Using a highly metastatic TNBC cell line with brain tropism (MDA-MB-231 Br4) and a library of 27 drug candidates in silico predicted to inhibit EGFR, PI3K, or EGFR plus PI3K, and to cross the blood-brain barrier, we evaluated the effects on cell viability. The half maximal inhibitory concentration (IC50) of the most cytotoxic ones was established, and cell cycle and death, as well as migration and EGFR pathway intervenient, were further evaluated. Two dual inhibitors emerged as the most promising drugs, with the ability to modulate cell cycle, death, migration and proliferation, morphology, and PI3K/AKT cascade players such as myocyte enhancer factor 2C (MEF2C) and forkhead box P1 (FOXP1). This work revealed EGFR/PI3K dual inhibitors as strong candidates to tackle brain metastatic TNBC cells.

FOXP1 inhibits pancreatic cancer growth by transcriptionally regulating IRF1 expression

FOXP1, known as a Forkhead-box (FOX) family protein, plays an important role in human tumorigenesis. However, the function and molecular mechanism of FOXP1 in pancreatic cancer (PC) remain unclear. Here, we report that PC patients with FOXP1 overexpression had a higher survival rate compared to patients with low- FOXP1 expression. Additionally, high expression of FOXP1 can markedly inhibit the growth of pancreatic cancer in vivo and in vitro, whereas low expression of FOXP1 effectively promoted the tumorigenesis. Mechanistically, FOXP1 could directly bind the IRF1 promoter, which triggered the transcriptional activity of IRF1. Taken together, FOXP1 suppressed PC growth via IRF1-dependent manner, serving as a potential prognostic biomarker for patients with PC.

FOXP1 and FOXO3a Are Prognostic Markers in Gallbladder Squamous Cell/Adenosquamous Carcinomas and Adenocarcinomas

The pathologic characteristics of squamous cell/adenosquamous carcinomas (SC/ASC) have not been well clarified. As a rare subtype of gallbladder cancer (GBC), no biological markers for diagnosis and prognosis are available. This research evaluated the expression of FOXP1 and FOXO3a in 69 SC/ASC, and 146 adenocarcinoma (AC) samples were analyzed via immunohistochemistry. SC/ASCs were associated with higher rates of lymph node metastasis, invasion, and patients older than 45 years comparing to ACs. FOXP1 and FOXO3a positivity rates were significantly lower in SC/ASC and AC samples from patients with large tumor size, a high TNM stage, lymph node metastasis, invasion, and no history of tumor resection (biopsy only). Positive FOXP1 expression levels were significantly decreased in cases of poorly differentiated AC. The univariate Kaplan-Meier analysis revealed that negative FOXP1 and FOXO3a expression, poor differentiation, large tumor size, high TNM stage, lymph node metastasis, invasion, and an inability to undergo curative resection were all closely associated with decreased overall survival in SC/ASC and AC patients. The multivariate cox regression analysis showed that negative FOXP1 and FOXO3a expression levels were independent predictors of poor prognosis in SC/ASC and AC patients. Our results indicate that negative FOXP1 and FOXO3a expression are closely associated with the pathogenesis, clinicopathologic properties, and prognosis of GBC patients. FOXP1 and FOXO3a may thus be biomarkers of GBC carcinogenesis, progression, and prognosis.

AKT1 Transcriptomic Landscape in Breast Cancer Cells

Overexpression and hyperactivation of the serine/threonine protein kinase B (AKT) pathway is one of the most common cellular events in breast cancer progression. However, the nature of AKT1-specific genome-wide transcriptomic alterations in breast cancer cells and breast cancer remains unknown to this point. Here, we delineate the impact of selective AKT1 knock down using gene-specific siRNAs or inhibiting the AKT activity with a pan-AKT inhibitor VIII on the nature of transcriptomic changes in breast cancer cells using the genome-wide RNA-sequencing analysis. We found that changes in the cellular levels of AKT1 lead to changes in the levels of a set of differentially expressed genes and, in turn, imply resulting AKT1 cellular functions. In addition to an expected positive relationship between the status of AKT1 and co-expressed cellular genes, our study unexpectedly discovered an inherent role of AKT1 in inhibiting the expression of a subset of genes in both unstimulated and growth factor stimulated breast cancer cells. We found that depletion of AKT1 leads to upregulation of a subset of genes—many of which are also found to be downregulated in breast tumors with elevated high AKT1 as well as upregulated in breast tumors with no detectable AKT expression. Representative experimental validation studies in two breast cancer cell lines showed a reasonable concurrence between the expression data from the RNA-sequencing and qRT-PCR or data from ex vivo inhibition of AKT1 activity in cancer patient-derived cells. In brief, findings presented here provide a resource for further understanding of AKT1-dependent modulation of gene expression in breast cancer cells and broaden the scope and significance of AKT1 targets and their functions.

Circulating tumor DNA predicts efficacy of a dual AKT/p70S6K inhibitor (LY2780301) plus paclitaxel in metastatic breast cancer: plasma analysis of the TAKTIC phase IB/II study

The phosphatidylinositol-3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathway is frequently activated in HER2-negative breast cancer and may play a role in taxane resistance. The phase IB/II TAKTIC trial (NCT01980277) has shown that combining a dual AKT and p70 ribosomal protein S6 kinase (p70S6K) inhibitor (LY2780301) taken orally with weekly paclitaxel in HER2-negative advanced breast cancer is feasible, with preliminary evidence of efficacy. We wanted to explore whether circulating tumor DNA (ctDNA) may be a surrogate marker of treatment efficacy in this setting. Serial plasma samples were collected and cell-free DNA was sequenced using low-coverage whole-genome sequencing, and analysis was completed with droplet digital PCR for some patients with driver mutations. Baseline tumor fraction (TF) and TF after 7 weeks on treatment were compared to progression-free survival (PFS) and overall response rate. We also explored circulating copy number alterations associated with treatment failure. Of the 51 patients enrolled in the TAKTIC trial, at least one plasma sample was available for 44 cases (96 time points). All patients with tumor TP53, PI3KCA or AKT1 mutations harbored at least one of these alterations in plasma. TF at inclusion was correlated to PFS (6m-PFS was 92% for ctDNAneg patients vs 68% for ctDNApos cases; HR=3.45, 95%CI [1.34-8.90], p=0.007). ctDNA status at week 7 was not correlated to prognosis. Even though most circulating copy number alterations were conserved at disease progression, some genomic regions of interest were altered in post-progression samples. In conclusions, ctDNA detection at baseline was associated with shorter PFS in patients included in the TAKTIC trial. Plasma-based copy number analysis may help to identify alterations involved in resistance to treatment.

NEAT1 Negatively Regulates Cell Proliferation and Migration of Neuroblastoma Cells by miR-183-5p/FOXP1 Via the ERK/AKT Pathway

Neuroblastoma, a malignant tumor of the sympathetic nervous system, is an aggressive extracranial tumor in childhood. Long noncoding RNAs (lncRNAs) have been discovered to play a key role in the eukaryotic regulatory gene network and be involved in a wide variety of biological processes. We observed that the expression of lncRNA nuclear-enriched abundant transcript-1 (NEAT1) was significantly decreased in human neuroblastoma tissues and cell lines, compared with the normal. We observed cell proliferation, migration, and invasion with Cell Counting Kit-8 assay, colony formation assay, and Transwell assay to investigate the effects of NEAT1, miR-183-5p, or FOXP1 on neuroblastoma cells. And we also used StarBase and luciferase reporter gene assay to predict and confirm the interaction of NEAT1, miR-183-5p, and FOXP1 in neuroblastoma cells. First, overexpression of NEAT1 suppressed cell proliferation and played a key role in cell migration and invasion. In addition, NEAT1 was demonstrated to directly interact with miR-183-5p and exerted its antioncogenic role in neuroblastoma by negatively regulating miR-183-5p expression. miR-183-5p suppressed the expression of FOXP1 and regulated cell proliferation and migration by directly targeting FOXP1 mRNA 3′-untranslated region. Moreover, FOXP1 antagonized the effect of miR-183-5p on the phosphorylation of extracellular-regulated kinase/protein kinase B (ERK/AKT), while FOXP1 siRNA increased the reduced phosphorylation of ERK/AKT caused by miR-183-5p inhibitor in neuroblastoma cells. Taken together, these data showed that NEAT1 negatively regulated cell proliferation and migration of neuroblastoma by the miR-183-5p/FOXP1 axis via suppression of the ERK/AKT pathway. Our findings may provide a new target for the study of pathogenesis and treatment of neuroblastoma.

Luminal Breast Cancer: Risk of Recurrence and Tumor-Associated Immune Suppression

Hormone-receptor positive (HR+) breast cancer (BC) (including the luminal A and the luminal B subtypes) is the most common type of tumor in women diagnosed with early-stage BC (EBC). It represents a highly heterogeneous subgroup that is characterized by different risks of relapse. The aim of this review is to discuss the possible role played by the immune response in predicting this risk, along with the most common clinical and pathological factors and molecular tools that have been developed and are already in use. As opposed to what has previously been observed in the most aggressive human epidermal growth factor receptor 2 (HER2)-positive and triple-negative breast cancer (TNBC) subtypes, a high proportion of tumor-infiltrating lymphocytes (TILs)-reflecting a spontaneous and pre-existing immune response to the tumor-has been linked to a worse prognosis in HR+ EBC. This work provides some immune biological rationale explaining these findings and provides the basics to understand the principal clinical trials that are testing immunotherapy in HR+ (luminal) BC.

Prazosin inhibits the proliferation, migration and invasion, but promotes the apoptosis of U251 and U87 cells via the PI3K/AKT/mTOR signaling pathway

Prazosin, an α-adrenergic receptor antagonist, is used to treat mild to moderate hypertension. It has recently been discovered that α-adrenergic receptors may have potential antitumor properties. Therefore, in the present study, the effect of prazosin on human glioblastoma and the underlying mechanism were investigated. Human glioblastoma U251 and U87 cells were treated with different concentrations of prazosin, and a Cell Counting Kit-8 assay was performed to investigate the effects of prazosin on cell proliferation. Transwell migration and invasion assays were used to assess the effects of prazosin on cell migration and invasion. Prazosin-induced apoptosis in U251 and U87 cells was detected by flow cytometry, and the protein expression levels of anti-apoptotic proteins and proteins related to the PI3K/AKT/mTOR signaling pathway were detected by western blotting. The results suggested that following treatment with prazosin, the proliferation, migration and invasion of U251 and U81 cells were decreased. By contrast, U251 and U81 cell apoptosis, as well as the protein expression levels of Bax and active Caspase-3 were increased after prazosin treatment (P<0.05). Bcl-2 levels were also decreased after prazosin treatment (P<0.05). Additionally, the expression of phosphorylated (p)-AKT and p-mTOR, P70 and cyclin D1 were decreased in U251 and U81 cells following prazosin treatment (P<0.05). The present study suggested that prazosin may suppress glioblastoma progression by downregulating the activity of the PI3K/AKT/mTOR signaling pathway.

Oncogenic Potential of Bisphenol A and Common Environmental Contaminants in Human Mammary Epithelial Cells

There is an ample epidemiological evidence to support the role of environmental contaminants such as bisphenol A (BPA) in breast cancer development but the molecular mechanisms of their action are still not fully understood. Therefore, we sought to analyze the effects of three common contaminants (BPA; 4-tert-octylphenol, OP; hexabromocyclododecane, HBCD) on mammary epithelial cell (HME1) and MCF7 breast cancer cell line. We also supplied some data on methoxychlor, MXC; 4-nonylphenol, NP; and 2-amino-1-methyl-6-phenylimidazo [4–b] pyridine, PhIP. We focused on testing the prolonged (two months) exposure to low nano-molar concentrations (0.0015–0.0048 nM) presumed to be oncogenic and found that they induced DNA damage (evidenced by upregulation of pH2A.X, pCHK1, pCHK2, p-P53) and disrupted the cell cycle. Some agents induced epigenetic (methylation) changes of tumor suppressor genes TIMP3, CHFR, ESR1, IGSF4, CDH13, and GSTP1. Obviously, the accumulation of these molecular alterations is an essential base for cancer development. Consistent with this, we observed that these agents increased cellular invasiveness through collagen. Cellular abilities to form colonies in soft agar were increased for MCF7. Toxic agents induced phosphorylation of protein kinase such as EGFR, CREB, STAT6, c-Jun, STAT3, HSP6, HSP27, AMPKα1, FAK, p53, GSK-3α/β, and P70S6 in HME1. Most of these proteins are involved in potential oncogenic pathways. Overall, these data clarify the molecular alterations that can be induced by some common environmental contaminants in mammary epithelial cells which could be a foundation to understand environmental carcinogenesis.

Molecular networks of FOXP family: dual biologic functions, interplay with other molecules and clinical implications in cancer progression

Though Forkhead box P (FOXP) transcription factors comprising of FOXP1, FOXP2, FOXP3 and FOXP4 are involved in the embryonic development, immune disorders and cancer progression, the underlying function of FOXP3 targeting CD4 + CD25+ regulatory T (Treg) cells and the dual roles of FOXP proteins as an oncogene or a tumor suppressor are unclear and controversial in cancers to date. Thus, the present review highlighted research history, dual roles of FOXP proteins as a tumor suppressor or an oncogene, their molecular networks with other proteins and noncoding RNAs, cellular immunotherapy targeting FOXP3, and clinical implications in cancer progression.

Critical roles of ARHGAP36 as a signal transduction mediator of Shh pathway in lateral motor columnar specification

During spinal cord development, Sonic hedgehog (Shh), secreted from the floor plate, plays an important role in the production of motor neurons by patterning the ventral neural tube, which establishes MN progenitor identity. It remains unknown, however, if Shh signaling plays a role in generating columnar diversity of MNs that connect distinct target muscles. Here, we report that Shh, expressed in MNs, is essential for the formation of lateral motor column (LMC) neurons in vertebrate spinal cord. This novel activity of Shh is mediated by its downstream effector ARHGAP36, whose expression is directly induced by the MN-specific transcription factor complex Isl1-Lhx3. Furthermore, we found that AKT stimulates the Shh activity to induce LMC MNs through the stabilization of ARHGAP36 proteins. Taken together, our data reveal that Shh, secreted from MNs, plays a crucial role in generating MN diversity via a regulatory axis of Shh-AKT-ARHGAP36 in the developing mouse spinal cord.

UNBS5162 inhibits SKOV3 ovarian cancer cell proliferation by regulating the PI3K/AKT signalling pathway

Ovarian cancer is the gynaecological malignancy with the highest mortality rate worldwide, and effective and safe therapeutic methods are limited. UNBS5162, a derivative of naphthalimide, has a clear inhibitory effect on the proliferation of various tumour cells in vitro and in vivo as a pan-antagonist of CXC chemokine ligand expression, but whether it serves a function in ovarian cancer remains unclear. The aim of the present study was to determine the effects of UNBS5162 on the proliferation, migration and invasion of ovarian cancer cells. The cell viability was detected using a Cell Counting Kit-8 (CCK-8) assay. The invasion and migration of SKOV3 cells were determined using Transwell assays. Cell apoptosis was determined using flow cytometry. The apoptosis-associated proteins and associated factors, such as phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signalling pathway members, were detected using western blot analysis. The CCK-8 assay revealed that SKOV3 cell viability was affected by UNBS5162 in a dose- and time-dependent manner. In Transwell assays, UNBS5162 inhibited cell invasion and migration. Furthermore, it was identified that UNBS5162 markedly increased the apoptosis rate of SKOV3 cells. Simultaneously, the expression of the anti-apoptotic protein B-cell lymphoma 2 (Bcl-2) was decreased and the expression of the pro-apoptotic proteins active caspase-3 and Bcl-2-associated X protein were increased in SKOV3 cells treated with UNBS5162. In addition, the expression levels of phospho (p-)AKT/total AKT, p-mammalian target of rapamycin (mTOR)/total mTOR, p-p70 S6 kinase (p70S6K)/total p70S6K and cyclin D1 were decreased in the UNBS5162-treated group. The results of the present study indicated that UNBS5162 inhibits proliferation, migration and invasion, and induces apoptosis in ovarian cancer cells, which may be regulated by the PI3K/AKT signalling pathway. These results suggest that UNBS5162 may be a potential novel drug for clinical ovarian cancer treatment.

Deletion of 3p13 is a late event linked to progression of TMPRSS2:ERG fusion prostate cancer

Introduction

Deletion of 3p13 is one of the most common alterations in prostate cancer preferentially occurring in tumors with TMPRSS2:ERG fusion. The cause for the striking association between 3p13 loss and ERG fusion is unknown.

Methods

Here, we made use of a preexisting heterogeneity prostate cancer tissue microarray including ten tissue spots from ten different tumor areas of 317 cancers to examine the spatial distribution of 3p13 deletions (determined by fluorescence in situ hybridization) in prostate cancer areas with and without ERG overexpression (determined by immunohistochemistry).

Results

3p13 deletions were found in 61 of 299 (20.4%) and ERG positivity in 174 of 317 (54.9%) interpretable cancers. The likelihood of 3p13 loss was twice as high in ERG-positive cancers (39/152, 25.7%) than in ERG-negative cancers (17/124, 13.7%, P=0.010). At least three tissue spots were interpretable for 3p13 deletion status in 279 cancers: only these were used for heterogeneity assessment. Among these tumors, 58 (20.8%) had a 3p13 deletion and 221 (79.2%) were undeleted. The majority of 3p13-deleted cancers showed marked intratumoral heterogeneity. Areas with and without 3p13 loss were found in 50 (18%) of 279 cancers with three or more interpretable tissue spots, while only eight (3%) tumors had a homogeneous 3p13 loss. Comparison with ERG data revealed that ERG fusion usually precede 3p13 deletions. In total, 26 (66.7%) of 39 cancers with ERG and 3p13 alteration had only focal 3p13 deletions in an otherwise ERG-positive background. In contrast, none of the cancers showed a pattern that would be consistent with 3p13 deletion preceding ERG fusion.

Conclusion

Our study identifies 3p13 deletion as a highly heterogeneous alteration in prostate cancer preferentially developing at rather late stages of progression in TMPRSS2:ERG fusion-positive tumors.

The role of TCF3 as potential master regulator in blastemal Wilms tumors

Wilms tumors are the most common type of pediatric kidney tumors. While the overall prognosis for patients is favorable, especially tumors that exhibit a blastemal subtype after preoperative chemotherapy have a poor prognosis. For an improved risk assessment and therapy stratification, it is essential to identify the driving factors that are distinctive for this aggressive subtype. In our study, we compared gene expression profiles of 33 tumor biopsies (17 blastemal and 16 other tumors) after neoadjuvant chemotherapy. The analysis of this dataset using the Regulator Gene Association Enrichment algorithm successfully identified several biomarkers and associated molecular mechanisms that distinguish between blastemal and nonblastemal Wilms tumors. Specifically, regulators involved in embryonic development and epigenetic processes like chromatin remodeling and histone modification play an essential role in blastemal tumors. In this context, we especially identified TCF3 as the central regulatory element. Furthermore, the comparison of ChIP-Seq data of Wilms tumor cell cultures from a blastemal mouse xenograft and a stromal tumor provided further evidence that the chromatin states of blastemal cells share characteristics with embryonic stem cells that are not present in the stromal tumor cell line. These stem-cell like characteristics could potentially add to the increased malignancy and chemoresistance of the blastemal subtype. Along with TCF3, we detected several additional biomarkers that are distinctive for blastemal Wilms tumors after neoadjuvant chemotherapy and that may provide leads for new therapeutic regimens.

MiR-206 is down-regulated and suppresses cell proliferation by targeting FOXP1 in brain gliomas

Aberrant expression of miR-206 has been repeatedly found and demonstrated to play crucial roles in cancers. However, the role of miR-206 in brain glioma remains unclear. To address this issue, we detected miR-206 expression of 60 gliomas and 18 normal peritumor tissues, and found that miR-206 is significantly down-regulated in gliomas. Further in silico analysis of 198 glioma samples from the Chinese Glioma Genome Atlas (CGGA) indicated that miR-206 is significantly down-regulated in high grade gliomas and that miR-206 predicts favorable patients' prognosis. Notably, we found that miR-206 expression is negatively correlated with Ki-67 staining, indicating a proliferative inhibition of miR-206 in gliomas. To explore the crucial role of miR-206 in gliomas, we constructed miR-206 stably overexpressed LN229 glioma cell lines and found that the proliferation is significantly inhibited. Through flow cytometry (FCM) analyses, we found that the apoptotic rate is increased and the cell cycle is arrested in LN229 cells after overexpression of miR-206. Bioinformatic analysis, qPCR, western blot and luciferase assay indicated that the Forkhead Box Protein 1 (FOXP1) is a direct target of miR-206 in gliomas. Overexpression of FOXP1 could partially rescue the proliferative inhibition in the miR-206 stably overexpressed LN229 cells. In summary, our results suggest that miR-206 might function as a tumor suppressor of gliomas by inhibition of proliferation and could serve as a promising candidate for therapeutic applications in glioma by targeting FOXP1.

Prucalopride Inhibits Proliferation of Ovarian Cancer Cells via Phosphatidylinositol 3-Kinase (PI3K) Signaling Pathway

BACKGROUND Ovarian cancer is the second most common malignant tumor of the female reproductive system and is the leading cause of death of gynecological malignancies, but at present there is no effective and safe therapy. There is no previously published report on the anti-cancer effect of prucalopride, which is a high-affinity 5-HT4 receptor. The aim of the present study was to determine whether prucalopride can inhibit proliferation of ovarian cancer cells. MATERIAL AND METHODS The cell viability was detected by use of the Cell Counting Kit-8 (CCK-8) assay. The invasion and migration of SKOV3 and OVCAR3 cells was detected by Transwell assay. The cell apoptosis was detected by apoptosis flow detection and Caspase-Glo 3/7 Assay Systems. The apoptosis-related proteins, autophagy marker proteins, and the related-factors of phosphatidylinositol 3-kinase (PI3K) were detected by Western blot. RESULTS The CCK-8 proliferation test showed that prucalopride inhibited the growth of ovarian cancer cell lines SKOV3 and OVCAR3. In the Transwell assay, prucalopride inhibited cell invasion and migration. Furthermore, we found the expression of anti-apoptotic protein Bcl-2 decreased, whereas the expression of pro-apoptotic protein Caspase3 and Bax increased in the SKOV3 cell line treated with prucalopride, as well as cleaved PARP. In addition, the expression of p-AKT, p-mTOR, and p70S6K decreased in the prucalopride-treated group, and the expression of autophagy marker protein LC3-II/I and Beclin1 significantly increased, whereas the expression of p62 protein decreased. CONCLUSIONS The present study reveals that in ovarian cancer cells, prucalopride inhibits proliferation, migration, and invasion, and induces apoptosis and autophagy, which may be regulated by the PI3K signaling pathway. These results suggest prucalopride has potential as a new drug for clinical ovarian cancer treatment.

Cytoplasmic FOXP1 expression is correlated with ER and calpain II expression and predicts a poor outcome in breast cancer

BACKGROUND

Nuclear forkhead box protein P1 (N-FOXP1) expression in invasive breast cancer has been documented in the literature. However, the FOXP1 expression patterns at different stages of breast cancer progression are largely unknown, and the significance of cytoplasmic FOXP1 (C-FOXP1) expression in breast cancer has not been well illustrated. The aims of this study were to investigate FOXP1 expression patterns in invasive ductal carcinoma (IDC), ductal carcinoma in situ (DCIS), atypical ductal hyperplasia (ADH) and usual ductal hyperplasia (UDH), and to analyze the clinicopathological relevance of C-FOXP1 and its prognostic value in IDC.

METHODS

N-FOXP1 and C-FOXP1 expression in cases of IDC, DCIS, ADH and UDH was determined using immunohistochemistry. The correlation between C-FOXP1 expression and clinicopathological parameters as well as the overall survival (OS) and disease-free survival (DFS) rates of patients with IDC were analyzed.

RESULTS

Exclusive N-FOXP1 expression was found in 85.0% (17/20), 40.0% (8/20), 12.2% (5/41) and 10.8% (9/83) of UDH, ADH, DCIS, and IDC cases, respectively, and exclusive C-FOXP1 expression was observed in 0% (0/20), 0% (0/20), 4.9% (2/41), and 31.3% (26/83) of the cases, respectively. Both N- and C-FOXP1 staining were observed in 15.0% (3/20), 60.0% (12/20), 82.9% (34/41) and 48.2% (40/83) of the above cases, respectively, while complete loss of FOXP1 expression was observed in only 9.6% (8/83) of IDC cases. Estrogen receptor (ER) expression in C-FOXP1-positive IDC cases (31/66, 47.0%) was significantly lower than that in C-FOXP1-negative cases (13/17, 76.5%) (p = 0.030). Calpain II expression was observed in 83.3% (55/66) of C-FOXP1-positive IDC cases, which was significantly higher than that in C-FOXP1-negative cases (9/17, 52.9%) (p = 0.007). Calpain II was significantly associated with pAKT (p = 0.029), pmTOR (p = 0.011), p4E-BP1 (p < 0.001) and p-p70S6K (p = 0.003) expression levels. The 10-year OS and DFS rates of the C-FOXP1-positive patients were 60.5% and 48.7%, respectively, both of which were lower than those of the C-FOXP1-negative patients (93.3, 75.3%). The OS curve showed a dramatic impact of C-FOXP1 status on OS (p = 0.045).

CONCLUSIONS

Cytoplasmic relocalization of FOXP1 protein was a frequent event in breast IDC. Calpain II might play an important role in nucleocytoplasmic trafficking of FOXP1 and the AKT pathway might be involved in this process. C-FOXP1 expression was inversely associated with ER expression and might be a predictor of poor OS in patients with IDC.

Mometasone furoate inhibits growth of acute leukemia cells in childhood by regulating PI3K signaling pathway

OBJECTIVES

Acute lymphoblastic leukemia (ALL) is the most common cancer before the age of 15 years, seriously endangering the health of children. The main treatment for Childhood ALL was pharmacotherapy. But these drugs have many side effects and some of them could develop drug resistance quickly. Mometasone furoate (MF) is an efficient glucocorticoid for topical treatment of inflammation on the skin, lung and nose.

METHODS

In this study, we investigated whether the MF had effects on ALL cells proliferation and migration.

RESULTS

The CCK-8 proliferation test showed that the cell viability was the lowest at 25 nM MF treatment and the increased OD value was time-dependent. In transwell assay, the number of CCRF-CEM cells was reduced in MF treated group. We found the expression of anti-apoptotic protein bcl-2 decreased the expression of pro-apoptotic protein caspase3 and bax increased in CCRF-CEM cell line treated with MF. The expression of p-AKT, p-mTOR, p70S6 K, vascular endothelial growth factor and CyclinD1 were decreased in MF treated group.

CONCLUSION

This study reveals that MF can inhibit proliferation and invasion/migration and induce apoptosis in Childhood ALL cells, which may be regulated by Phosphatidylinositol 3-kinase signaling pathway. These results suggest MF may be a potential new drug target for clinical ALL treatment.

Telmisartan inhibits NSCLC A549 cell proliferation and migration by regulating the PI3K/AKT signaling pathway

Expression of angiotensin II (Ang II), a key biological peptide in the renin-angiotensin system, is closely associated with the occurrence and development of cancer. Ang II binds two receptor subtypes, the Ang II type 1 receptor (AT1R) and the AT2R, to mediate a series of biological effects. Telmisartan, a specific AT1R blocker, has been reported to have potential as an anticancer drug for treating renal cancer. In the present study, whether telmisartan had an effect on non-small cell lung cancer (NSCLC) cell proliferation and migration was investigated. The Cell Counting kit-8 assay revealed that telmisartan significantly inhibited the growth of the NSCLC A549 cell line in a time- and dose-dependent manner. In a transwell assay, telmisartan significantly inhibited cellular invasion and migration. Furthermore, it was determined that the expression of the anti-apoptotic protein B-cell lymphoma was decreased, and that of the pro-apoptotic proteins caspase-3 and Bcl-associated X increased in the A549 cells treated with telmisartan. Additionally, levels of phosphorylated RAC serine/threonine-protein kinase (p-AKT), p-mechanistic target of rapamycin, p70-S6 kinase and cyclin D1 was decreased in the telmisartan-treated group. Therefore, the current study reveals that telmisartan-induced NSCLC apoptosis may be regulated via the phosphoinositide 3-kinase/AKT signaling pathway, which indicates that it may be a potential novel drug for clinical NSCLC treatment.

Regulatory effects of antitumor agent matrine on FOXO and PI3K-AKT pathway in castration-resistant prostate cancer cells

We previously demonstrated that matrine could inhibit the proliferating, migrating, as well as invading processes of both PC-3 and DU145 cells. However, the underlying molecular mechanisms have not yet been clearly defined. In this study, using various techniques such as high throughput sequencing technology, bioinformatics, quantitative real-time PCR, and immunoblot analysis, we aimed to understand whether matrine serves as a novel regulator of FOXO and PI3K-AKT signaling pathway. DU145 and PC-3 cell lines were cultured for 24 h in vitro. Cells were treated with either matrine or control serum for 48 h, followed by extraction of total RNA. The RNA was sequenced using HiSeq 2500 high-throughput sequencing platform (Illumina). A gene library was established and quality analysis of read data carried out. Integrated database from the website DAVID was used to analyze Gene Ontology (GO), and Kyoto encyclopedia of genes and genomes (KEGG) pathway of differential genes was used for pathway analysis, screening for fold differences of more than two times. The FOXO and PI3K-AKT signaling pathways were screened, and expression levels of mRNA and core protein detected by real-time PCR and immunoblotting, respectively. High throughput sequencing and GO analysis revealed that differentially expressed genes before and after treatment played an important role in cell metabolic process, growth process, anatomical structure formation, cellular component organization, and biological regulation. KEGG signal pathway analysis revealed that FOXO and PI3K-AKT signal pathways had a significant difference between before and after matrine-treated androgen-independent prostate cancer cells PC-3 and DU145. Real-time PCR showed that matrine treatment led to a significant increase in the expression levels of FOXO1A, FOXO3A, FOXO4, and FOXO6 in DU145 and PC-3 cells (P<0.01 or P<0.05), whereas the PI3K expression levels decreased (P<0.01). Similarly, immunoblotting revealed a significant increase (P<0.05) in the expression levels of FOXO1A FOXO3A, FOXO4, and FOXO6 in both PC-3 and DU145 cells, whereas PI3K expression levels decreased (P<0.05). Matrine had a broad regulating effect on the mRNA expression profiles of both PC-3 and DU145 cells. Matrine may inhibit cell proliferation, migration, as well as invasion, and induce apoptosis in both PC-3 and DU145 cells through FOXO and PI3K-AKT signaling pathways. Matrine could therefore be used as a complementary drug to present chemotherapeutic agents, for treating androgen-independent prostate cancer.

LncRNA MALAT1 acts as an oncogene in multiple myeloma through sponging miR-509-5p to modulate FOXP1 expression

Previous studies showed that Metastasis associated lung adenocarcinoma transcript 1(MALAT1) acted as an oncogene in Multiple Myeloma (MM). However, the underlying mechanism of MALAT1 in MM remains unclear. Quantitative real time-PCR(qRT-PCR) was used to determine MALAT1 expression in MM samples and cell lines. in vitro function assays were used to determine the function of MALAT1 on MM cells. Bioinformatics tools were used to predict the targets of MALAT1 and miR-509-5p, respectively. Furthermore, rescue experiments were performed to further confirm the regulation of miR-509-5p by MALAT1. In the present study, our data showed that MALAT1 expression was upregulated in MM samples and cell lines. In function assays, we confirmed that MALAT1 inhibition significantly suppressed cells proliferation, induced cells apoptosis, arrested cells in G1/S phase, and inhibited MM cells growth in vivo. Furthermore, MALAT1 was identified to function as a competitive endogenous RNA (ceRNA) for miR-509-5p to promote MM cell viability. Additionally, our results suggested that miR-509-5p targeted the 3’-UTR of FOXP1 to suppress MM cells progression. Meanwhile, our results showed that miR-509-5p inhibitors significantly abrogated the decreased expression of FOXP1 induced by MALAT1 suppression, indicating that MALAT1 could positively regulate FOXP1 expression by sponging miR-509-5p. Our findings suggested that MALAT1/miR-509-5p/FOXP1 axis was one of the key signalings in mediating MM cell growth, and further indicated that MALAT1 could act as a novel diagnostic marker and therapeutic target for the treatment of MM.

Deletion of 3p13-14 locus spanning FOXP1 to SHQ1 cooperates with PTEN loss in prostate oncogenesis

A multigenic locus at 3p13-14, spanning FOXP1 to SHQ1, is commonly deleted in prostate cancer and lost broadly in a range of cancers but has unknown significance to oncogenesis or prognosis. Here, we report that FOXP1-SHQ1 deletion cooperates with PTEN loss to accelerate prostate oncogenesis and that loss of component genes correlates with prostate, breast, and head and neck cancer recurrence. We demonstrate that Foxp1-Shq1 deletion accelerates prostate tumorigenesis in mice in combination with Pten loss, consistent with the association of FOXP1-SHQ1 and PTEN loss observed in human cancers. Tumors with combined Foxp1-Shq1 and Pten deletion show increased proliferation and anaplastic dedifferentiation, as well as mTORC1 hyperactivation with reduced Akt phosphorylation. Foxp1-Shq1 deletion restores expression of AR target genes repressed in tumors with Pten loss, circumventing PI3K-mediated repression of the androgen axis. Moreover, FOXP1-SHQ1 deletion has prognostic relevance, with cancer recurrence associated with combined loss of PTEN and FOXP1-SHQ1 genes.

FOXP1 enhances tumor cell migration by repression of NFAT1 transcriptional activity in MDA-MB-231 cells

Until now, forkhead box P1 (FOXP1) has been identified as a tumor suppressor in several correlation studies in breast cancer. Although FOXP1 is defined as a transcriptional repressor that interacts with other transcription factors in various mechanistic studies, there is no study that explains its repressor functions in breast cancer biology. This study demonstrated the repressor function of FOXP1 on nuclear factor of activated T cells (NFAT1) and the migratory effect of this repression in MDA-MB-231 breast cancer cells. Co-immunoprecipitation experiments were performed for the investigation of protein-protein interaction between two transcription factors. Protein-protein interaction on DNA was investigated with EMSA and transcriptional effects of FOXP1 on NFAT1, luciferase reporter assay was performed. Wound healing assay was used to analyze the effects of overexpression of FOXP1 on tumor cell migration. This study showed that FOXP1 has protein-protein interaction with NFAT1 on DNA and enhances breast cancer cell migration by repressing NFAT1 transcriptional activity and FOXP1 shows oncogenic function by regulating breast cancer cell motility.

The prostate cancer immunome: In silico functional analysis of antigenic proteins from microarray profiling with IgG

The study of the immunome of prostate cancer (PCa) and characterization of autoantibody signature from differentially reactive antigens can uncover disease stage proteins, reveal enriched networks and even expose aberrant cellular mechanisms during the disease process. By conducting plasma IgG profiling on protein microarrays presenting 5449 unique human proteins expressed in 15 417 E. coli human cDNA expression clones, we elucidated 471 (21 higher reactive in PCa) differentially reactive antigens in 50 PCa versus 49 patients with benign prostate hyperplasia (BPH) at initial diagnosis. Functional analyzes show that the immune-profile of PCa compared to BPH control samples is significantly enriched in features targeting Cellular assembly, Cell death and pathways involved in Cell cycle, translation, and assembly of proteins as EIF2 signaling, PCa related genes as AXIN1 and TP53, and ribosomal proteins (e.g. RPS10). An overlap of 61 (out of 471) DIRAGs with the published 1545 antigens from the SEREX database has been found, however those were higher reactive in BPH. Clinical relevance is shown when antibody-reactivities against eight proteins were significantly (p < 0.001) correlated with Gleason-score. Herewith we provide a biological and pathophysiological characterization of the immunological layer of cancerous (PCa) versus benign (BPH) disease, derived from antibody profiling on protein microarrays.

FOXO factors and breast cancer: outfoxing endocrine resistance

The majority of metastatic breast cancers cannot be cured and present a major public health problem worldwide. Approximately 70% of breast cancers express the estrogen receptor, and endocrine-based therapies have significantly improved patient outcomes. However, the development of endocrine resistance is extremely common. Understanding the molecular pathways that regulate the hormone sensitivity of breast cancer cells is important to improving the efficacy of endocrine therapy. It is becoming clearer that the PI3K-AKT-forkhead box O (FOXO) signaling axis is a key player in the hormone-independent growth of many breast cancers. Constitutive PI3K-AKT pathway activation, a driver of breast cancer growth, causes down-regulation of FOXO tumor suppressor functions. This review will summarize what is currently known about the role of FOXOs in endocrine-resistance mechanisms. It will also suggest potential therapeutic strategies for the restoration of normal FOXO transcriptional activity.