Prognostic value of decreased FOXP1 protein expression in various tumors: a systematic review and meta-analysis

Long non-coding RNA NEAT1 exacerbates NLRP3-mediated pyroptosis in allergic rhinitis through regulating the PTBP1/FOXP1 cascade

BACKGROUND

Allergic Rhinitis (AR) is a prevalent chronic non-infectious inflammation affecting the nasal mucosa. NLRP3-mediated pyroptosis of epithelial cells plays a pivotal role in AR pathogenesis. Herein, we evaluated the impact of the long non-coding RNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1) on NLR family pyrin domain containing 3 (NLRP3)-mediated pyroptosis in AR.

METHODS

Nasal inflammation levels in ovalbumin (OVA)-induced AR mice were assessed using HE staining, and NLRP3 expression was evaluated through immunohistochemistry. ELISA was utilized to detect OVA-specific IgE, IL-6, IL-5, and inflammatory cytokines (IL-1β, IL-18). Human nasal epithelial cells (HNEpCs) stimulated with IL4/IL13 were used to analyze the mRNA and protein levels of associated genes utilizing RT-qPCR and western blot, respectively. Cell viability and pyroptosis were assessed by CCK-8 and flow cytometry. The targeting relationship between NEAT1, PTBP1 and FOXP1 were analyzed by RIP and RNA pull down assays. FISH and IF analysis were performed to assess the co-localization of NEAT1 and PTBP1.

RESULTS

In both the AR mouse and cellular models, increased levels of NEAT1, PTBP1 and FOXP1 were observed. AR mice exhibited elevated inflammatory infiltration and pyroptosis, evidenced by enhanced expressions of OVA-specific IgE, IL-6, and IL-5, NLRP3, Cleaved-caspase 1, GSDMD-N, IL-1β and IL-18. Functional assays revealed that knockdown of PTBP1 or NEAT1 inhibited pyroptosis while promoting the proliferation of IL4/IL13-treated HNEpCs. Mechanistically, NEAT1 directly interacted with PTBP1, thereby maintaining FOXP1 mRNA stability. Rescue assays demonstrated that FOXP1 upregulation reversed the inhibitory effects of silencing NEAT1 or PTBP1 on IL4/IL13-stimulated pyroptosis activation in HNEpCs.

CONCLUSION

NEAT1 acts as a RNA scaffold for PTBP1, activating the PTBP1/FOXP1 signaling cascade, subsequently triggering NLRP3-mediated pyroptosis in HNEpCs, and ultimately promoting AR progression. These findings highlight some new insights into the pathogenesis of AR.

Acute myeloid leukemia with unreported translocation (x; 3) (q24; p13): A case report

Key Clinical Message

Novel and rare chromosomal aberrations in AML are important to understand, particularly if associated with tumorigenesis and how they contribute to prognostic risk. It is important that acute leukemia be treated right away. Herein, novel (x; 3) (q24; p13) is described.

Abstract

Acute myeloid leukemia (AML) is a cancer of the blood and bone marrow. It is the most common type of acute leukemia in adults. This type of cancer usually gets worse quickly if it is not treated. Here, we report an unusual case of AML with an unreported translocation associated with AML.

Identification of FOXP1 as a favorable prognostic biomarker and tumor suppressor in intrahepatic cholangiocarcinoma

BACKGROUND

Forkhead-box protein P1 (FOXP1) has been proposed to have both oncogenic and tumor-suppressive properties, depending on tumor heterogeneity. However, the role of FOXP1 in intrahepatic cholangiocarcinoma (ICC) has not been previously reported.

METHODS

Immunohistochemistry was performed to detect FOXP1 expression in ICC and normal liver tissues. The relationship between FOXP1 levels and the clinicopathological characteristics of patients with ICC was evaluated. Finally, in vitro and in vivo experiments were conducted to examine the regulatory role of FOXP1 in ICC cells.

RESULTS

FOXP1 was significantly downregulated in the ICC compared to their peritumoral tissues (p < 0.01). The positive rates of FOXP1 were significantly lower in patients with poor differentiation, lymph node metastasis, invasion into surrounding organs, and advanced stages (p < 0.05). Notably, patients with FOXP1 positivity had better outcomes (overall survival) than those with FOXP1 negativity (p < 0.05), as revealed by Kaplan-Meier survival analysis. Moreover, Cox multivariate analysis showed that negative FOXP1 expression, advanced TNM stages, invasion, and lymph node metastasis were independent prognostic risk factors in patients with ICC. Lastly, overexpression of FOXP1 inhibited the proliferation, migration, and invasion of ICC cells and promoted apoptosis, whereas knockdown of FOXP1 had the opposite role.

CONCLUSION

Our findings suggest that FOXP1 may serve as a novel outcome predictor for ICC as well as a tumor suppressor that may contribute to cancer treatment.

miR-34a-FOXP1 Loop in Ovarian Cancer

Ovarian cancer (OC) is the main cause of gynecological cancer mortality in most developed countries. microRNA (miR) expression dysregulation has been highlighted in human cancers, and miR-34a is found to be downregulated and associated with inhibition of tumor growth and invasion in several malignancies, including OC. The winged helix transcription factor forkhead box P1 (FOXP1) is reported as either an oncogene or tumor suppressor in various cancers. This study aimed to elucidate potential clinical and biological associations of miR-34a and transcription factor FOXP1 in OC. We investigated nine OC patients' blood samples and two OC cell lines (SKOV-3 and OVCAR-3) using quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR) to determine both miR-34a and FOXP1 expressions. We have found that miR-34a and FOXP1 are reversely correlated in both in vitro and in vivo. Inhibition of miR-34a transiently led to upregulation of FOXP1 mRNA expression and increased cellular invasion in vitro. Our data indicate that miR-34a could be a potential biomarker for improving the diagnostic efficiency of OC, and miR-34a overexpression may reduce OC pathogenesis by targeting FOXP1.

Immunohistochemistry technique for effect of gold nanoparticles, laser, and photodynamic therapy on FoxP1 level in infected mice with mammary adenocarcinoma

The current study was performed to investigate the treatment of tumors with gold nanoparticles, laser, and photodynamic therapy (PDT) by using an immunohistochemistry method and to investigate the expression of FOXP1 in infected mice with mammary adenocarcinoma whether it can be used as an indicator to estimate the recovery of tissues from cancer disease. Twenty-five albino female mice were used in this research; they were divided into five groups, four groups were infected with mammary adenocarcinoma, and then three of them were treated with gold nanoparticles, laser, and PDT, respectively, while the fourth group was left without any treatment and represents the positive control, and the fifth group (normal mice) represents the negative control. Tissue sections were taken from different groups of mice in order to estimate FOXP1 expression in infected mice by using an immunohistochemistry assay. FOXP1 expression was higher in the tumor and kidney tissues of the mice treated with PDT than that in mice treated with either gold nanoparticles or laser alone. Also, in the group of mice treated with laser, FOXP1 expression was higher than the expression in mice which were treated with gold nanoparticles but lower than that in mice which were treated with PDT. FOXP1 can be used as a biomarker for the prognosis outcome of breast and other solid tumors, as well as it considers a key tumor suppressor. PDT is the best choice to treat cancer in comparison to using either gold nanoparticles or the laser separately.

Neglected, yet significant role of FOXP1 in T-cell quiescence, differentiation and exhaustion

FOXP1 is ubiquitously expressed in the human body and is implicated in both physiological and pathological processes including cancer. However, despite its importance the role of FOXP1 in T-cells has not been extensively studied. Although relatively few phenotypic and mechanistic details are available, FOXP1 role in T-cell quiescence and differentiation of CD4+ subsets has recently been established. FOXP1 prevents spontaneous T-cell activation, preserves memory potential, and regulates the development of follicular helper and regulatory T-cells. Moreover, there is growing evidence that FOXP1 also regulates T-cell exhaustion. Altogether this makes FOXP1 a crucial and highly undervalued regulator of T-cell homeostasis. In this review, we discuss the biology of FOXP1 with a focus on discoveries made in T-cells in recent years.

Comprehensive Analysis of Prognostic and immune infiltrates for FOXPs Transcription Factors in Human Breast Cancer

Forkhead-box-P family include FOXP1/2/3/4 and its clinical significance still remains unclear in breast cancer (BRCA). We analysed the expressions of FOXPs in BRCA patients to determine diagnostic and prognostic values. Our results indicated that the transcriptional levels of FOXP3/4 were up-regulated in BRCA patients, but FOXP2 were down-regulated. No statistically significant correlation were found between the expression levels of FOXPs in Pathologic stage. FOXP2/3 had a significantly high AUC value in the detection of breast cancer, with 96.8% or 95.7% in accuracy respectively. Our study also suggested that BRCA patients with high transcription levels of FOXP1/2/4 were significantly associated with longer Overall Survival (OS). In contrast, BRCA patients with high transcription level of FOXP3 was not statistically related with OS. Our work revealed that FOXPs were closely related to the alteration of extensive immune checkpoints in breast invasive carcinoma. Additionally, FOXP3 has a significant positive correlation with PDCD1, CD274, CTLA4 and TMB in breast cancer, and FOXP3 expression showed a statistically significant correlation with infiltration of immune cells. Finally, we found that FOXP3 expression predicted the breast cancer cells response to anticancer drugs. Altogether, our work strongly suggested that FOXPs could serve as a biomarker for tumor detection, therapeutic design and prognosis.

Enhanced Efficacy and Increased Long-Term Toxicity of CNS-Directed, AAV-Based Combination Therapy for Krabbe Disease

Infantile globoid cell leukodystrophy (GLD, Krabbe disease) is a demyelinating disease caused by the deficiency of the lysosomal enzyme galactosylceramidase (GALC) and the progressive accumulation of the toxic metabolite psychosine. We showed previously that central nervous system (CNS)-directed, adeno-associated virus (AAV)2/5-mediated gene therapy synergized with bone marrow transplantation and substrate reduction therapy (SRT) to greatly increase therapeutic efficacy in the murine model of Krabbe disease (Twitcher). However, motor deficits remained largely refractory to treatment. In the current study, we replaced AAV2/5 with an AAV2/9 vector. This single change significantly improved several endpoints primarily associated with motor function. However, nearly all (14/16) of the combination-treated Twitcher mice and all (19/19) of the combination-treated wild-type mice developed hepatocellular carcinoma (HCC). 10 out of 10 tumors analyzed had AAV integrations within the Rian locus. Several animals had additional integrations within or near genes that regulate cell growth or death, are known or potential tumor suppressors, or are associated with poor prognosis in human HCC. Finally, the substrate reduction drug L-cycloserine significantly decreased the level of the pro-apoptotic ceramide 18:0. These data demonstrate the value of AAV-based combination therapy for Krabbe disease. However, they also suggest that other therapies or co-morbidities must be taken into account before AAV-mediated gene therapy is considered for human therapeutic trials.

Identification of MicroRNAs With In Vivo Efficacy in Multiple Myeloma-related Xenograft Models

BACKGROUND/AIM

Multiple myeloma is a B-cell neoplasm, which can spread within the marrow of the bones forming many small tumors. In advanced disease, multiple myeloma can spread to the blood as plasma cell leukemia. In some cases, a localized tumor known as plasmacytoma is found within a single bone. Despite the approval of several agents such as melphalan, corticosteroids, proteasome inhibitors, thalidomide-based immuno-modulatory agents, histone deacetylase inhibitors, a nuclear export inhibitor and monoclonal antibodies daratuzumab and elatuzumab, the disease presently remains uncurable.

MATERIALS AND METHODS

In order to define new targets and treatment modalities we searched the literature for microRNAs, which increase or inhibit in vivo efficacy in multiple-myeloma-related xenograft models.

RESULTS AND CONCLUSION

We identified six up-regulated and twelve down-regulated miRs, which deserve further preclinical validation.

mRNA expression profile analysis reveals a C-MYC/miR-34a pathway involved in the apoptosis of diffuse large B-cell lymphoma cells induced by Yiqichutan treatment

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of adult non-Hodgkin's lymphoma (NHL). While DLBCL is sensitive to chemotherapy, a certain percentage of patients with DLBCL experience relapse. Previous studies have indicated that Yiqichutan treatment, which was developed to treat NHL, can inhibit DLBCL cell growth, but the mechanism is not fully understood. The present study identified 991 differentially expressed mRNAs, with 498 upregulated and 493 downregulated (P<0.05), in SUDHL-6 cells exposed to Yiqichutan. The underlying pathways included the Jak/Stat and PI3K signaling pathways. In total, six representative mRNAs were selected for validation with reverse transcription-quantitative PCR (RT-qPCR), and a strong correlation was identified between the RT-qPCR results and microarray data. Since the transcription factor C-MYC is involved in both the Jak/Stat and PI3K signaling pathways, C-MYC and its associated microRNA (miR) were selected for further analysis. It was found that knockdown of C-MYC increased miR-34a expression levels, inhibited forkhead box P1 (Foxp1) expression levels and promoted DLBCL cell apoptosis. In addition, the miR-34a mimics further enhanced the role of C-MYC knockdown. It was demonstrated that, the expression levels of apoptotic factors Bax and poly (ADP-ribose) polymerase were significantly upregulated with C-MYC knockdown and miR-34a mimics in SUDHL-6 cells, while the Bcl2 expression level was significantly reduced. Moreover, Yiqichutan treatment increased miR-34a expression levels and induced apoptosis, as well as reducing Foxp1 expression level in SUDHL-6 cells. Therefore, the present results suggested that Yiqichutan treatment affected DLBCL cells via several signaling pathways. Furthermore, Yiqichutan may inhibit the proliferation of DLBCL cells by blocking the C-MYC/miR-34a signaling pathway.

Prognostic Significance of FOXC1 in Various Cancers: A Systematic Review and Meta-Analysis

BACKGROUND

Forkhead box C1 (FOXC1), a member of the Forkhead box (Fox) transcription factor family, plays an essential role in lymphatic vessel formation, angiogenesis and metastasis. Observational studies examining the relationship between the protein biomarker FOXC1 and breast cancer prognosis have reported conflicting findings. This systematic review and meta-analysis evaluates the prognostic value of the FOXC1 expression in association with patient survival in breast cancer and other types of cancers in order to identify the overall prognostic effectiveness of FOXC1.

METHODS

This study followed the guidelines established in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We conducted a broad search on the online bibliographic databases EMBASE, PubMed, Science Direct and Scopus, limiting search to publications from 2010 to 2018. The prognostic value was demonstrated by a random effects model meta-analysis using the hazard ratio (HR) with 95% confidence interval (CI) for overall survival (OS) in various cancer patients. The heterogeneity was measured by the I² statistic. Publication bias and quality assessment for the selected articles was performed. Subgroup analysis was conducted based on the data available from the selected articles.

RESULTS

A total of 16 studies met the predefined selection criteria established for our systematic review and meta-analysis, with multiple studies using diverse methodologies and reported on differing clinical outcomes, falling under a common banner of FOXC1 expression and survival in cancer. Overall, we observed a statistically non-significant association between FOXC1 protein expression and patients survival (HR: 1.186 and 95% CI 1.122-1.255, p = 0.000, I² = 88.83%).

CONCLUSION

In summary, FOXC1 protein expression indicated poor survival outcome in various carcinomas, especially in patients with breast cancer, suggesting it as a possible biomarker for the prognosis in multiple carcinomas. Further clinical evaluation and large-scale cohort studies are required to accurately identify its possible clinical utility.

microRNA-605 inhibits the oncogenicity of non-small-cell lung cancer by directly targeting Forkhead Box P1

Background and aims: microRNA-605 (miR-605) is dysregulated in multiple cancers and plays crucial roles in regulating cancer progression. However, little is known about the expression pattern and detailed roles of miR-605 in non-small-cell lung cancer (NSCLC). Thus, in this study, we evaluated miR-605 expression in NSCLC along with its clinical significance. More importantly, the detailed roles and the underlying molecular mechanisms of miR-605 in NSCLC were explored.

Material and methods: Quantitative reverse transcription polymerase chain reaction (RT-qPCR) was employed to detect miR-605 expression in NSCLC tissues and cell lines. A series of experiments were performed to determine the effects of miR-605 upregulation on NSCLC cell proliferation, apoptosis, migration and invasion in vitro and tumor growth in vivo. In addition, the downstream regulatory mechanisms of miR‐605 action in NSCLC cells were explored.

Results: Decreased expression of miR-605 was frequently detected in NSCLC tissues and cell lines. Low expression of miR-605 was significantly correlated with the tumor size, TNM stage, and distane metastasis in NSCLC patients. Exogenous miR-605 expression inhibited proliferation, increased apoptosis, and inhibited metastasis of NSCLC cells in vitro. Additionally, miR-605 overexpression hindered the growth of NSCLC cells in vivo. Furthermore, Forkhead Box P1 (FOXP1) was identified as a direct target gene of miR-605 in NSCLC cells. Moreover, FOXP1 was highly expressed in NSCLC cells and showed an inverse correlation with miR-605 expression levels. Besides, silencing of FOXP1 simulated roles similar to miR-605 upregulation in NSCLC cells. FOXP1 reintroduction partially abolished the anticancer effects of miR-605 in NSCLC cells.

Conclusion: Our results revealed that miR-605 inhibited the oncogenicity of NSCLC cells in vitro and in vivo by directly targeting FOXP1, suggesting the importance of the miR-605/FOXP1 pathway in the malignant development of NSCLC.

FOXP1 negatively regulates tumor infiltrating lymphocyte migration in human breast cancer

Background

FOXP1, a transcriptional regulator of lymphocyte development, is abnormally expressed in some human tumors. This study investigated FOXP1-mediated regulation of tumor infiltrating lymphocytes (TIL) in untreated primary breast cancer (BC).

Methods

FOXP1 expression was analyzed in tissues from primary untreated breast tumors, BC cell lines and the METABRIC gene expression BC dataset. Cytokine and chemokine expression and lymphocyte migration in response to primary tumor supernatants (SN) was compared between FOXP1^hi and FOXP1^lo primary BC.

Finding

FOXP1 expression was higher in estrogen receptor positive compared to negative BC. FOXP1^hi tumors were significantly associated with lower TIL and fewer tertiary lymphoid structures (TLS) compared to FOXP1^lo BC. Silencing FOXP1 in BC cell lines positively impacted cytokine and chemokine expression with the inverse effect associated with overexpression. CXCL9, CXCL10, CXCL11, CXCL13, CX3CL, CCL20, IL2, IL21, GZMB and IFNG expression decreased while IL10 and TGFβ increased in FOXP1^hi compared to FOXP1^lo primary BC. Lymphocyte migration using primary BC supernatants detected decreased mobility toward FOXP1^hi supernatants. FOXP1^lo BC expresses higher levels of chemokines driving TIL migration. The METABRIC gene expression dataset analysis show FOXP1 expression is associated with unfavorable BC outcomes.

Interpretation

These data identify FOXP1 as an important negative regulator of immune responses in BC via its regulation of cytokine and chemokine expression.

Fund

Belgian Fund for Scientific Research (FNRS 3.4513.12F) and Opération Télévie (7.4636.13F and 7.4609.15F), Fonds J.C. Heuson and Fonds Lambeau-Marteaux.

Foxp1 Is Indispensable for Ductal Morphogenesis and Controls the Exit of Mammary Stem Cells from Quiescence

Long-lived quiescent mammary stem cells (MaSCs) are presumed to coordinate the dramatic expansion of ductal epithelium that occurs through the different phases of postnatal development, but little is known about the molecular regulators that underpin their activation. We show that ablation of the transcription factor Foxp1 in the mammary gland profoundly impairs ductal morphogenesis, resulting in a rudimentary tree throughout life. Foxp1-deficient glands were highly enriched for quiescent Tspan8^hi MaSCs, which failed to become activated even in competitive transplantation assays, thus highlighting a cell-intrinsic defect. Foxp1 deletion also resulted in aberrant expression of basal genes in luminal cells, inferring a role in cell-fate decisions. Notably, Foxp1 was uncovered as a direct repressor of Tspan8 in basal cells, and deletion of Tspan8 rescued the defects in ductal morphogenesis elicited by Foxp1 loss. Thus, a single transcriptional regulator Foxp1 can control the exit of MaSCs from dormancy to orchestrate differentiation and development.

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.

Bioinformatics analysis of key differentially expressed genes in well and poorly differentiated endometrial carcinoma

Endometrial carcinoma (EC) is one of the most common gynecological malignancies. The malignant degree increases between grade (G)1 and G3, and EC of G3 usually presents a high recurrence rate and poor prognosis. Therefore, the present study aimed to examine the principal genes associated with the degree of differentiation in EC. The microarrays GSE17025, GSE24537 and GSE35784, representing data of Type I EC samples of G1 and G3, were downloaded from the Gene Expression Omnibus. The differentially expressed genes (DEGs) and differentially expressed micro (mi)RNAs (DEMs) were identified, followed by functional enrichment analyses and interaction network construction. In total, 83 upregulated and 130 downregulated DEGs with the same expression trends in two mRNA datasets were screened. The upregulated DEGs were primarily enriched in 'mitotic cell cycle process', 'cell cycle process' and 'mitotic cell cycle'; while the downregulated DEGs were enriched in 'cellular component assembly involved in morphogenesis', 'cell projection organization' and 'microtubule‑based movement'. From the protein‑protein interaction network, DNA topoisomerase IIα, kinesin family member 11, cyclin B1 and BUB1 mitotic checkpoint serine/threonine were identified as foremost hub genes. One module was extracted and involved in 'mitotic cell cycle process' and 'cell cycle process'. Based on the analysis of DEMs and the miRNA‑target regulatory network, miRNA‑9 may be the most important upregulated DEM, and the DEGs forkhead box P1 and cyclin E1 may serve vital roles in the differentiation of EC. In conclusion, principal genes were identified that may be determinants of the carcinogenesis of poorly differentiated EC, which may facilitate the examination of potential molecular mechanisms. These genes may additionally help identify candidate biomarkers and novel therapeutic targets for poorly differentiated EC.

Upregulation of FOXP1 is a new independent unfavorable prognosticator and a specific predictor of lymphatic dissemination in cutaneous melanoma patients

Background

FOXP1 is a pleiotropic protein that plays important roles in immune responses (B-cell development regulation and differentiation of monocyte), organ development (cardiac valves, lung, and esophagus), and neuronal development. Besides being the primary regulator of normal human tissue development, FOXP1 also plays a role in tumorigenesis. However, the potential value of FOXP1 expression in tumor prognosis remains controversial. FOXP1 expression was assessed in tumor cells (TCs) and stromal cells (SCs) of cutaneous melanomas with the aim of analyzing the associations between FOXP1 expression and clinicopathological characteristics. We believe this article to be the first report analyzing the correlations between FOXP1 expression and clinicopathological, as well as histological, characteristics in melanoma.

Materials and methods

In total, 96 formalin-fixed, paraffin-embedded primary cutaneous melanoma tissue specimens were subjected to immunohistochemical analysis for FOXP1, and the results were correlated with classical clinicopathological features and patient survival.

Results

FOXP1 overexpression in TCs was strongly associated with the presence of metastases in sentinel lymph nodes (p=0.0003, OR=11.66) and positive status of regional lymph nodes (p=0.0006, OR=22.15). In 96% (52 of 54) of patients presenting with low FOXP1 expression, no clinical or histopathological features of lymphatic dissemination were observed. However, thinner and nonulcerated tumors were reported to have increased numbers of FOXP1-positive SCs. In addition, a strong association was observed between FOXP1 upregulation in SCs and the absence of regional lymph node metastases. There was a significant correlation between FOXP1 upregulation in TCs and shorter cancer-specific overall survival (log-rank test, p=0.0040) and disease-free survival (log-rank test, p=0.0021). FOXP1 expression was confirmed in multivariate analysis as a factor that significantly unfavorably impacts prognosis in melanoma patients (HR=3.14, p=0.0299, adjusted for age, Breslow thickness, and sex).

Conclusion

The findings from this study indicate that FOXP1 has a major role in melanoma progression, which makes it a candidate for molecular target-based cancer therapy.

PRMT5 Is a Critical Regulator of Breast Cancer Stem Cell Function via Histone Methylation and FOXP1 Expression

Breast cancer progression, treatment resistance, and relapse are thought to originate from a small population of tumor cells, breast cancer stem cells (BCSCs). Identification of factors critical for BCSC function is therefore vital for the development of therapies. Here, we identify the arginine methyltransferase PRMT5 as a key in vitro and in vivo regulator of BCSC proliferation and self-renewal and establish FOXP1, a winged helix/forkhead transcription factor, as a critical effector of PRMT5-induced BCSC function. Mechanistically, PRMT5 recruitment to the FOXP1 promoter facilitates H3R2me2s, SET1 recruitment, H3K4me3, and gene expression. Our findings are clinically significant, as PRMT5 depletion within established tumor xenografts or treatment of patient-derived BCSCs with a pre-clinical PRMT5 inhibitor substantially reduces BCSC numbers. Together, our findings highlight the importance of PRMT5 in BCSC maintenance and suggest that small-molecule inhibitors of PRMT5 or downstream targets could be an effective strategy eliminating this cancer-causing population.

Systematic review and meta-analysis of the utility of long non-coding RNA GAS5 as a diagnostic and prognostic cancer biomarker

The growth arrest-specific 5 transcript (GAS5) is a long non-coding RNA (lncRNA) involved in the control of cell cycle progression and apoptosis in a wide variety of cells. To determine the clinical value of GAS5 expression in cancer patients, we performed a systematic review and meta-analysis exploring its association with the diagnosis, prognosis, and clinicopathological characteristics of cancer. Ten articles on prognosis, 15 on clinicopathology, and 5 on diagnosis were analyzed. Overall results showed that decreased GAS5 expression associated with unfavorable overall survival (OS) (HR = 2.50, 95%CI: 1.85–3.38, P < 0.001) and disease-free survival (DFS) (HR = 2.24, 95%CI: 1.58–3.18, P < 0.001) in several tumor types. Down-regulation of GAS5 correlated with poor recurrence-free survival (RFS) in hepatocellular carcinoma (HR = 2.40, 95%CI: 1.27–4.54, P = 0.007), and was associated with lymph node metastasis (OR = 1.92, 95% CI: 1.44–2.57, P < 0.001), distant metastasis (OR = 2.7, 95% CI: 1.05–6.97, P = 0.040), poor clinical stage (OR = 0.26, 95% CI: 0.18–0.38, P < 0.001), larger tumor size (OR = 3.21, 95% CI: 2.08–4.95, P < 0.001), and poor tumor differentiation (OR = 1.98, 95% CI: 1.40–2.80, P < 0.001). Pooled results of diagnostic data analysis showed that GAS5 exhibited a sensitivity of 0.76 and specificity of 0.64 for cancer diagnosis, and an area under the curve of 0.76 (95% CI: 0.72–0.80) indicated moderate diagnostic accuracy. This meta-analysis suggests GAS5 lncRNA may be a useful diagnostic and prognostic cancer biomarker, and may be especially useful for identifying patients prone to developing lymph node or distant metastasis.