miR-30a inhibits androgen-independent growth of prostate cancer via targeting MYBL2, FOXD1, and SOX4

Prostate cancer and the cell cycle: Focusing on the role of microRNAs

Prostate cancer is the most frequent solid tumor in terms of incidence and ranks second only to lung cancer in terms of cancer mortality among men. It has a considerably high mortality rate; around 375,000 deaths occurred worldwide in 2020. In 2024, the American Cancer Society estimated that the number of new prostate cancer cases will be around 299,010 cases, and the estimated deaths will be around 32,250 deaths only in the USA. Cell cycle dysregulation is inevitable in cancer etiology and is targeted by various therapies in cancer treatment. MicroRNAs (miRNAs) are small, endogenous, non-coding regulatory molecules involved in both normal and abnormal cellular events. One of the cellular processes regulated by miRNAs is the cell cycle. Although there are some exceptions, tumor suppressor miRNAs could potentially arrest the cell cycle by downregulating several molecular machineries involved in catalyzing the cell cycle progression. In contrast, oncogenic miRNAs (oncomirs) help the cell cycle to progress by targeting various regulatory proteins such as retinoblastoma (Rb) or cell cycle inhibitors such as p21 or p27, and hence may contribute to prostate cancer progression; however, this is not always the case. In this review, we emphasize how a dysregulated miRNA expression profile is linked to an abnormal cell cycle progression in prostate cancer, which subsequently paves the way to a new therapeutic option for prostate cancer.

NCAPD3 exerts tumor-promoting effects in prostatic cancer via dual impact on miR-30a-5p by STAT3-MALAT1 and MYC

Non-SMC condensin II complex subunit D3 (NCAPD3) is a subunit of the non-structural maintenance of chromosomes condensin II complex, which involves chromosome condensation and segregation during mitosis. NCAPD3 has recently been demonstrated as a crucial oncogenic factor. However, the underlying mechanism of NCAPD3 in prostate cancer (PCa) remains not completely clear. In this study, we confirmed that lncRNA MALAT1 was induced by NCAPD3-STAT3, and the expression of miR-30a-5p was controlled by NCAPD3 in PCa cells by miRNA-seq. Through quantitative real-time PCR, fluorescence in situ hybridization, western blotting, and immunohistochemistry assay, we demonstrated that miR-30a-5p was lowly expressed in PCa cells and tissues compared to the controls, which was contrary to NCAPD3 expression and markedly downregulated by NCAPD3. Then, MALAT1 was analyzed for the complementary sequence in the potential interaction with miR-30a-5p by using the predicted target module of public databases. Dual-luciferase reporter assay and RNA immunoprecipitation were carried out to verify that MALAT1 functioned as a sponge for miR-30a-5p to reduce miR-30a-5p expression. Meanwhile, MYC acted as a transcriptional repressor to directly bind the promoter of the miR-30a-5p located gene and repress the miR-30a-5p expression. Furthermore, the upregulation of NCAPD3 on cell viability and migration was significantly attenuated in PC-3 cells when miR-30a-5p was overexpressed. NCAPD3 overexpression also accelerated tumor growth in the xenograft mouse model and repressed miR-30-5p. In summary, this work elucidates NCAPD3 inhibits miR-30a-5p through two pathways: increasing STAT3-MALAT1 to sponge miR-30a-5p and increasing MYC to directly inhibit miR-30a-5p transcription, which could serve as potential therapeutic targets for prostate cancer.

Dissecting multifunctional roles of forkhead box transcription factor D1 in cancers

As a member of the forkhead box (FOX) family of transcription factors (TF), FOXD1 has recently been implicated as a crucial regulator in a variety of human cancers. Accumulating evidence has established dysregulated and aberrant FOXD1 signaling as a prominent feature in cancer development and progression. However, there is a lack of systematic review on this topic. Here, we summarized the present understanding of FOXD1 functions in cancer biology and reviewed the downstream targets and upstream regulatory mechanisms of FOXD1 as well as the related signaling pathways within the context of current reports. We highlighted the functional features of FOXD1 in cancers to identify the future research consideration of this multifunctional transcription factor and potential therapeutic strategies targeting its oncogenic activity.

Tumor-Suppressive and Immunomodulating Activity of miR-30a-3p and miR-30e-3p in HNSCC Cells and Tumoroids

Head and neck squamous cell carcinomas (HNSCCs) are heterogeneous tumors, well known for their frequent relapsing nature. To counter recurrence, biomarkers for early diagnosis, prognosis, or treatment response prediction are urgently needed. miRNAs can profoundly impact normal physiology and enhance oncogenesis. Among all of the miRNAs, the miR-30 family is frequently downregulated in HNSCC. Here, we determined how levels of the 3p passenger strands of miR-30a and miR-30e affect tumor behavior and clarified their functional role in LA-HNSCC. In a retrospective study, levels of miR-30a-3p and miR-30e-3p were determined in 110 patients and correlated to overall survival, locoregional relapse, and distant metastasis. miR-30a/e-3p were expressed in HNSCC cell lines and HNSCC patient-derived tumoroids (PDTs) to investigate their effect on tumor cells and their microenvironment. Both miRNAs were found to have a prognosis value since low miR-30a/e-3p expression correlates to adverse prognosis and reduces overall survival. Low expression of miR-30a/e-3p is associated with a shorter time until locoregional relapse and a shorter time until metastasis, respectively. miR-30a/e-3p expression downregulates both TGF-βR1 and BMPR2 and attenuates the survival and motility of HNSCC. Results were confirmed in PDTs. Finally, secretomes of miR-30a/e-3p-transfected HNSCC activate M1-type macrophages, which exert stronger phagocytic activities toward tumor cells. miR-30a/e-3p expression can discriminate subgroups of LA-HNSCC patients with different prognosis, making them good candidates as prognostic biomarkers. Furthermore, by targeting members of the TGF-β family and generating an immune-permissive microenvironment, they may emerge as an alternative to anti-TGF-β drugs to use in combination with immune checkpoint inhibitors.

Deciphering the role of MitomiRs in cancer: A comprehensive review

MicroRNAs (miRNAs) are short non-coding RNAs that regulate many metabolic and signal transduction pathways. The role of miRNAs, usually found in the cytoplasm, in regulating gene expression and cancer progression has been extensively studied in the last few decades. However, very recently, miRNAs were found to localize in the mitochondria. MiRNAs that specifically localize in the mitochondria and the cytoplasmic miRNAs associated with mitochondria that directly or indirectly modulate specific mitochondrial functions are termed as "mitomiRs". Although it is not clear about the origin of mitomiRs that are situated within mitochondria (nuclear or mitochondrial origin), it is evident that they have specific functions in modulating gene expression and regulating important mitochondrial metabolic pathways. Through this review, we aim to delineate the mechanisms by which mitomiRs alter mitochondrial metabolic pathways and influence the initiation and progression of cancer. We further discuss the functions of particular mitomiRs, which have been widely studied in the context of mitochondrial metabolism and oncogenic signaling pathways. Based on the current knowledge, we can conclude that mitomiRs contribute significantly to mitochondrial function and metabolic regulation, and that dysregulation of mitomiRs can aid the proliferation of cancer cells. Therefore, the less explored area of mitomiRs' biology can be an important topic of research investigation in the future for targeting cancer cells.

MiRNA and Potential Prognostic Value in Non-Smoking Females with Lung Adenocarcinoma by High-Throughput Sequencing

Background

Non-smoking females with lung adenocarcinoma (LUAD) account for a unique disease entity and miRNA play critical roles in cancer development and progression. The purpose of this study is to explore prognosis-related differentially expressed miRNA (DEmiRNA) and establish a prognostic model for non-smoking females with LUAD.

Methods

Eight specimens were collected from thoracic surgery of non-smoking females with LUAD and implemented the miRNA sequencing. The intersection of our miRNA sequencing data and TCGA database were identified as common DEmiRNA. Then, we predicted the target genes of the common DEmiRNAs (DETGs) and explored the functional enrichment and prognosis of DETGs. A risk model by overall survival (OS)-related DEmiRNA was constructed based on multivariate Cox regression analyses.

Results

A total of 34 overlapping DEmiRNA were obtained. The DETGs were enriched in pathways including "Cell cycle" and "miRNAs in cancer". The DETGs (KPNA2, CEP55, TRIP13, MYBL2) were risk factors, significantly related to OS, progression-free survival (PFS), and were also hub genes. ScRNA-seq data also validated the expression of the four DETGs. Hsa-mir-200a, hsa-mir-21, and hsa-mir-584 were significantly associated with OS. The prognostic prediction model constructed by the 3 DEmiRNA could effectively predict OS and can be used as an independent prognostic factor of non-smoking females with LUAD.

Conclusion

Hsa-mir-200a, hsa-mir-21, and hsa-mir-584 can serve as potential prognostic predictors in non-smoking females with LUAD. A novel prognostic model based on the three DEmiRNAs was also constructed to predict the survival of non-smoking females with LUAD and showed good performance. The result of our paper can be helpful for treatment and prognosis prediction for non-smoking females with LUAD.

A trio of tumor suppressor miRNA downregulates CREB5 dependent transcription to modulate neoadjuvant hormonal therapy sensitivity

Neoadjuvant hormonal therapy (NHT) prior to radical prostatectomy (RP) is an approach that can potentially maximize survival outcomes in prostate cancer (PCa) patients with high-risk disease. Unfortunately, subsets of patients do not respond well to such hormonal therapy. We previously identified several pathological parameters in predicting differences in response to NHT of PCa. However, little is known about the potential role and mechanism of miRNAs mediated NHT resistance (NHT-R) in PCa. Here we demonstrate that miR-l42-3p, miR-150-5p and miR-342-3p are the top downregulated miRNAs in PCa tissues with NHT-R. Functional analysis reveals that the three miRNAs inhibit cell proliferation in vitro. Transfection of miRNAs mimics strengthens the inhibitory effects of bicalutamide and enzalutamide to PCa cells. Luciferase reporter assay reveals that CREB5 is the common target of these three miRNAs. Clinically, high expression level of CREB5 correlates with high Gleason score, advanced tumor stage and NHT-R in PCa tissues. CREB5 expression promotes antiandrogen therapy resistance in LNCaP cells and IL6 signaling pathway may be involved in this process. In all, our findings highlight an important role of miR-142-3p, miR-150-5p, and miR-342-3p in contributing NHT-R by targeting CREB5 in PCa.

A miRNA-based gene therapy nanodrug synergistically enhances pro-inflammatory antitumor immunity against melanoma

MicroRNA (miRNA)-based gene therapy is a robust approach to treating human cancers. However, the low target specificity and safety issues associated with viral vectors have limited the clinical use of miRNA therapeutics. In the present study, we aimed to develop a biocompatible nanocarrier to deliver the tumor suppressor miR-30a-5p for gene therapy of ocular melanoma. The quasi-mesoporous magnetic nanospheres (MMNs) were prepared by polyelectrolytes-mediated self-assembling Fe₃O₄ nanocrystals; the cationic polymer capped quasi-mesoporous inner tunnels of the MMNs facilitate high miRNA loading and protect from nuclease degradation. Then, the outer layer of the MMNs was modified with a disulfide bond bridged very low molecular weight polyethyleneimine (PEI) network to form redox-responsive nanospheres (rMMNs) that enhance the miRNA payload and enable miRNA release under glutathione-dominant tumor microenvironment. The miR-30a-5p loaded rMMNs nanodrug (miR-30a-5p@rMMNs) upregulated miR-30a-5p level and inhibited malignant phenotypes of ocular melanoma by targeting the transcription factor E2F7 both in vitro and in vivo. Additionally, rMMNs act as an enhancer to increase cancer cell apoptosis by modulating M1-like macrophage polarization and activating Fenton reaction. Thus, the rMMNs is a promising miRNA carrier for gene therapy and could enhance pro-inflammatory immunity in melanoma and other cancers. STATEMENT OF SIGNIFICANCE: • miR-30a-5p@rMMNs inhibited malignant phenotypes of ocular melanoma both in vitro and in vivo. • The rMMNs promoted M1 macrophage polarization thus synergistically enhancing pro-inflammatory anti-tumor immunity against melanoma. • The rMMNs showed no obvious toxicity under the injection dose.

FOXD1-dependent RalA-ANXA2-Src complex promotes CTC formation in breast cancer

BACKGROUND

Early metastasis is a key factor contributing to poor breast cancer (BC) prognosis. Circulating tumor cells (CTCs) are regarded as the precursor cells of metastasis, which are ultimately responsible for the main cause of death in BC. However, to date molecular mechanisms underlying CTC formation in BC have been insufficiently defined.

METHODS

RNA-seq was carried out in primary tissues from early-stage BC patients (with CTCs≥5 and CTCs = 0, respectively) and the validation study was conducted in untreated 80 BC patients. Multiple in vitro and in vivo models were used in functional studies. Luciferase reporter, ChIP-seq, CUT&Tag-seq, and GST-pulldown, etc. were utilized in mechanistic studies. CTCs were counted by the CanPatrol™ CTC classification system or LiquidBiospy™ microfluidic chips. ERK1/2 inhibitor SCH772984 was applied to in vivo treatment.

RESULTS

Highly expressed FOXD1 of primary BC tissues was observed to be significantly associated with increased CTCs in BC patients, particularly in early BC patients. Overexpressing FOXD1 enhanced the migration capability of BC cells, CTC formation and BC metastasis, via facilitating epithelial-mesenchymal transition of tumor cells. Mechanistically, FOXD1 was discovered to induce RalA expression by directly bound to RalA promotor. Then, RalA formed a complex with ANXA2 and Src, promoting the interaction between ANXA2 and Src, thus increasing the phosphorylation (Tyr23) of ANXA2. Inhibiting RalA-GTP form attenuated the interaction between ANXA2 and Src. This cascade culminated in the activation of ERK1/2 signal that enhanced metastatic ability of BC cells. In addition, in vivo treatment with SCH772984, a specific inhibitor of ERK1/2, was used to dramatically inhibit the CTC formation and BC metastasis.

CONCLUSION

Here, we report a FOXD1-dependent RalA-ANXA2-Src complex that promotes CTC formation via activating ERK1/2 signal in BC. FOXD1 may serve as a prognostic factor in evaluation of BC metastasis risks. This signaling cascade is druggable and effective for overcoming CTC formation from the early stages of BC.

Therapeutic targets and signaling pathways of active components of QiLing decoction against castration-resistant prostate cancer based on network pharmacology

QiLing decoction (QLD) is a traditional Chinese medicine compound. This study aims to explore the therapeutic effect of QLD in castration-resistant prostate cancer (CRPC) and its potential bio-targets. A total of 51 active components and QLD 149 targets were identified using bioinformatics analysis. Additionally, five optimal hub target genes were screened including tumor protein P53 (TP53), interleukin-6 (IL-6), vascular endothelial growth factor-A (VEGF-A), caspase-3 (CASP-3), and estrogen receptor-1 (ESR-1). The interrelated network between active components of QLD and their potential targets was constructed. The molecular function, biological processes, and signaling pathways of QLD-against CRPC were identified. Moreover, QLD was found to efficiently exert a repressive effect on CRPC tumor growth mainly by suppressing the activation of HIF-α/VEGFA and TNF-α/IL6 signaling pathways, and increasing the P53 expression level. These results successfully indicated the potential anti-CRPC mechanism of the active components of QLD.

Anti-cancer function of microRNA-30e is mediated by negative regulation of HELLPAR, a noncoding macroRNA, and genes involved in ubiquitination and cell cycle progression in prostate cancer

Prostate cancer (PCa) progression relies on androgen receptor (AR) function, making AR a top candidate for PCa therapy. However, development of drug resistance is common, which eventually leads to development of castration‐resistant PCa. This warrants a better understanding of the pathophysiology of PCa that facilitates the aberrant activation of key signaling pathways including AR. MicroRNAs (miRNAs) function as regulators of cancer progression as they modulate various cellular processes. Here, we demonstrate a multidimensional function of miR‐30e through the regulation of genes involved in various signaling pathways. We noted loss of miR‐30e expression in prostate tumors, which, when restored, led to cell cycle arrest, induction of apoptosis, improved drug sensitivity of PCa cells and reduced tumor progression in xenograft models. We show that experimental upregulation of miR‐30e reduces expression of mRNAs including AR, FBXO45, SRSF7 and MYBL2 and a novel long noncoding RNA (lncRNA) HELLPAR, which are involved in cell cycle, apoptosis and ubiquitination, and the effects could be rescued by inhibition of miR‐30e expression. RNA immunoprecipitation analysis confirmed direct interactions between miR‐30e and its RNA targets. We noted a newly identified reciprocal relationship between miR‐30e and HELLPAR, as inhibition of HELLPAR improved stabilization of miR‐30e. Transcriptome profiling and quantitative real‐time PCR (qRT‐PCR) validation of miR‐30e‐expressing PCa cells showed differential expression of genes involved in cell cycle progression, apoptosis and ubiquitination, which supports our in vitro study. This study demonstrates an integrated function of miR‐30e on dysregulation of miRNA/lncRNA/mRNA axes that may have diagnostic and therapeutic significance in aggressive PCa.

MYBL2 is a Novel Independent Prognostic Biomarker and Correlated with Immune Infiltrates in Prostate Cancer

Purpose

MYB proto-oncogene like 2 (MYBL2) is a member of the MYB family of transcription factor genes and overexpressed in many cancers. We investigated the role of MYBL2 in the malignant progression of prostate cancer (PCa) and its relationship with immune infiltrates in PCa.

Methods

Gene expression level, clinicopathological parameters, Gene Ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway, tumor immune infiltration analysis were based on The Cancer Genome Atlas (TCGA) dataset. Gene set enrichment analysis (GSEA) and single-sample gene set enrichment analysis (ssGSEA) were conducted to analyze the correlation between MYBL2 and immune infiltrates. The data processing analysis based on R language. The relationship between MYBL2 expression and immune response in PCa was analyzed on TIMER 2.0.

Results

MYBL2 was overexpressed in PCa patients, and correlated with T-stage, Gleason score, primary therapy outcome and progress free interval (PFI) event. The multivariate Cox regression analysis revealed MYBL2 was an independent risk factor for PFI (HR=1.250, 95% CI=1.016–1.537, p=0.035). The receiver operating characteristic (ROC) curve for MYBL2 (AUC=0.887) and nomogram also confirmed the diagnostic value of MYBL2 in the treatment of PCa patients. Based on mRNA expression of MYBL2, PCa patients were divided into MYBL2-high group and MYBL2-low group, and analysis of MYBL2 associated KEGG and GO pathways using R language revealed that 6 immune-related signaling pathways were enriched in MYBL2-high expression phenotype. GSEA analysis showed that 3 hallmark gene sets related to immune response were significantly enriched in MYBL2-high group, ssGSEA analysis found that MYBL2 expression correlated with the expression of many tumor immune lymphocytes (CD8+T cells, neutrophil cells, macrophage cells and so on) and immune check point inhibitors (CD276, BTLA, TNFRSF18, HAVCR2 and CD70).

Conclusion

MYBL2 is a novel independent prognostic biomarker and MYBL2 may play a crucial role in tumor immune microenvironment of PCa.

E2F transcription factor 1/small nucleolar RNA host gene 18/microRNA-338-5p/forkhead box D1: an important regulatory axis in glioma progression

This study aims to probe the biological functions of long non-coding RNA small nucleolar RNA host gene 18 (SNHG18) on glioma cells and its underlying mechanism. In this study, SNHG18 expression in glioma tissues was quantified employing GEPIA database; quantitative real-time PCR was adopted to examine the expressions of SNHG18, microRNA-338-5p (miR-338-5p) and forkhead box D1 (FOXD1) mRNA in glioma tissues and cell lines; cell proliferation, migration and invasion were detected utilizing cell counting kit-8, EdU and Transwell assays; Western blot was utilized to quantify the protein expressions of E-cadherin, N-cadherin, Vimentin and FOXD1; dual-luciferase reporter gene and RNA immunoprecipitation experiments were utilized to validate the targeting relationships between SNHG18 and miR-338-5p, as well as miR-338-5p and FOXD1 mRNA 3ʹUTR; dual-luciferase reporter gene and chromatin immunoprecipitation assays were utilized to verify the binding of E2F transcription factor 1 (E2F1) to the SNHG18 promoter region. It was revealed that, SNHG18 expression in glioma was up-regulated and associated with unfavorable prognosis of the patients; knockdown of SNHG18 repressed the malignant biological behaviors of glioma cells, enhanced E-cadherin expression and repressed N-cadherin and Vimentin expressions. MiR-338-5p was a target of SNHG18, and SNHG18 promoted the expression of FOXD1 by decoying miR-338-5p. Additionally, E2F1 could bind to the promoter of SNHG18 to elevate its expression. In conclusion, SNHG18 accelerates glioma progression via regulating the miR-338-5p/FOXD1 axis.

Cervical cancer progression is regulated by SOX transcription factors: Revealing signaling networks and therapeutic strategies

Cervical cancer is the fourth common gynecologic cancer and is considered as second leading cause of death among women. Various strategies are applied in treatment of cervical cancer including radiotherapy, chemotherapy and surgery. However, cervical cancer cells demonstrate aggressive behavior in advanced phases, requiring novel strategies in their elimination. On the other hand, SOX proteins are transcription factors capable of regulating different molecular pathways and their expression varies during embryogenesis, disease development and carcinogenesis. In the present review, our aim is to reveal role of SOX transcription factors in cervical cancer. SOX transcription factors play like a double-edged sword in cancer. For instance, SOX9 possesses both tumor-suppressor and tumor-promoting role in cervical cancer. Therefore, exact role of each SOX members in cervical cancer has been discussed to direct further experiments for revealing other functions. SOX proteins can regulate proliferation and metastasis of cervical cancer cells. Furthermore, response of cervical cancer cells to chemotherapy and radiotherapy is tightly regulated by SOX transcription factors. Different downstream targets of SOX proteins such as Wnt signaling, EMT and Hedgehog have been identified. Besides, upstream mediators such as microRNAs, lncRNAs and circRNAs can regulate SOX expression in cervical cancer. In addition to pre-clinical studies, role of SOX transcription factors as prognostic and diagnostic tools in cervical cancer has been shown.

FOXD1 expression in head and neck squamous carcinoma: a study based on TCGA, GEO and meta-analysis

Forkhead box D1 (FOXD1) is a new member of FOX transcription factor family. FOXD1 has demonstrated multi-level roles during normal development and several diseases' pathogenesis. However, litter is known about the role of FOXD1 in the progression of head and neck squamous cancer (HNSC). In the present study, we analyzed FOXD1 expression pattern using TCGA dataset, GEO datasets, HNSC cell lines and HNSC tissues. Then, we analyzed the correlation between FOXD1 expression and clinical characteristics, and evaluated the prognostic value of FOXD1 in HNSC. Moreover, we assessed the relationship between FOXD1 expression and tumor environment (TME) and immune cell infiltration using ESTIMATE and CIBERSORT algorithms. Finally, we predicted the FOXD1-related biological processes and signal pathways. FOXD1 was up-regulated in HNSC tissues in TCGA datasets, validated by GEO datasets, HNSC cell lines and HNSC tissues. FOXD1 expression was significantly associated with tumor site and HPV infection. Univariate and multivariate Cox regression analyses showed that FOXD1 expression was an independent prognostic factor. Moreover, we found that the proportions of naïve B cells, plasma cells, and resting dendritic cells were negatively correlated with FOXD1 expression, otherwise, the proportion of activated mast cells was positively correlated with FOXD1 expression using CIBERSORT algorithm. GSEA analyses revealed that FOXD1 was mainly involved in cancer-related signaling pathway and metabolism-related pathways. FOXD1 was a potential oncogene, and might represent an indicator for predicting overall survival of HNSC patients. Moreover, many cancer-related pathways and metabolism-related processes may be regulated by FOXD1.

FOXD1 is a prognostic biomarker and correlated with macrophages infiltration in head and neck squamous cell carcinoma

Background: Forkhead Box D1 (FOXD1) is differentially expressed in various tumors. However, its role and correlation with immune cell infiltration remains uncertain in head and neck squamous cell carcinoma (HNSC).

Methods: FOXD1 expression was analyzed in The Cancer Genome Atlas (TCGA) pan-cancer data. The clinical prognosis influence of FOXD1 was evaluated by clinical survival data of TCGA. Enrichment analysis of FOXD1 was performed using R packages ‘clusterProfiler’. We downloaded the immune cell infiltration score of TCGA samples from published articles, and analyzed the correlation between immune cell infiltration level and FOXD1 expression.

Results: FOXD1 was highly expressed and associated with poorer overall survival (OS, P<0.0001), disease-specific survival (DSS, P=0.00011), and progression-free interval (PFI, P<0.0001) in HNSC and some other tumors. In addition, FOXD1 expression was significantly correlated with infiltration of immune cells. Tumor-associated macrophages (TAMs) infiltration increased in tissues with high FOXD1 expression in HNSC. Immunosuppressive genes such as PD-L1, IL-10, TGFB1, and TGFBR1 were significantly positively correlated with FOXD1.

Conclusions: Our study suggests FOXD1 to be an oncogene and act as an indicator of poor prognosis in HNSC. FOXD1 might contribute to the TAM infiltration in HNSC. High FOXD1 may be associated with tumor immunosuppression status.

MYBL2 disrupts the Hippo-YAP pathway and confers castration resistance and metastatic potential in prostate cancer

Rationale: Resistance to androgen-deprivation therapy (ADT) associated with metastatic progression remains a challenging clinical task in prostate cancer (PCa) treatment. Current targeted therapies for castration-resistant prostate cancer (CRPC) are not durable. The exact molecular mechanisms mediating resistance to castration therapy that lead to CRPC progression remain obscure. Methods: The expression of MYB proto-oncogene like 2 (MYBL2) was evaluated in PCa samples. The effect of MYBL2 on the response to ADT was determined by in vitro and in vivo experiments. The survival of patients with PCa was analyzed using clinical specimens (n = 132) and data from The Cancer Genome Atlas (n = 450). The mechanistic model of MYBL2 in regulating gene expression was further detected by subcellular fractionation, western blotting, quantitative real-time PCR, chromatin immunoprecipitation, and luciferase reporter assays. Results: MYBL2 expression was significantly upregulated in CRPC tissues and cell lines. Overexpression of MYBL2 could facilitate castration-resistant growth and metastatic capacity in androgen-dependent PCa cells by promoting YAP1 transcriptional activity via modulating the activity of the Rho GTPases RhoA and LATS1 kinase. Importantly, targeting MYBL2, or treatment with either the YAP/TAZ inhibitor Verteporfin or the RhoA inhibitor Simvastatin, reversed the resistance to ADT and blocked bone metastasis in CRPC cells. Finally, high MYBL2 levels were positively associated with TNM stage, total PSA level, and Gleason score and predicted a higher risk of metastatic relapse and poor prognosis in patients with PCa. Conclusions: Our results reveal a novel molecular mechanism conferring resistance to ADT and provide a strong rationale for potential therapeutic strategies against CRPC.

Establishment of Novel DNA Methylation-Based Prostate Cancer Subtypes and a Risk-Predicting Eight-Gene Signature

Prostate cancer (PCa) is the most common malignant tumor affecting males worldwide. The substantial heterogeneity in PCa presents a major challenge with respect to molecular analyses, patient stratification, and treatment. Least absolute shrinkage and selection operator was used to select eight risk-CpG sites. Using an unsupervised clustering analysis, called consensus clustering, we found that patients with PCa could be divided into two subtypes (Methylation_H and Methylation_L) based on the DNA methylation status at these CpG sites. Differences in the epigenome, genome, transcriptome, disease status, immune cell composition, and function between the identified subtypes were explored using The Cancer Genome Atlas database. This analysis clearly revealed the risk characteristics of the Methylation_H subtype. Using a weighted correlation network analysis to select risk-related genes and least absolute shrinkage and selection operator, we constructed a prediction signature for prognosis based on the subtype classification. We further validated its effectiveness using four public datasets. The two novel PCa subtypes and risk predictive signature developed in this study may be effective indicators of prognosis.

FOXD1 Repression Potentiates Radiation Effectiveness by Downregulating G3BP2 Expression and Promoting the Activation of TXNIP-Related Pathways in Oral Cancer

Simple Summary

Radioresistance remains a critical issue in treating oral cancer patients. This study was thus aimed to identify a potential drug target for enhancing the therapeutic effectiveness of irradiation and uncover a possible mechanism for radioresistance in oral cancer. Here we show that FOXD1, a gene encoding forkhead box d1 (Foxd1), is significantly upregulated in primary tumors compared to normal tissues and serves as a poor prognostic marker in oral cancer patients receiving radiotherapy. FOXD1 repression by a gene knockdown experiment dramatically enhanced the cytotoxic efficacy of irradiation probably via activating the p53-related DNA repairing pathways and reinforcing the T cell-mediated immune responses in oral cancer cells. Our findings demonstrate that FOXD1 may play a pivotal role in conferring radioresistance, which might provide a new strategy to combat the irradiation-insensitive oral cancer cells via therapeutically targeting FOXD1 activity.

Abstract

Radiotherapy is commonly used to treat oral cancer patients in the current clinics; however, a subpopulation of patients shows poor radiosensitivity. Therefore, the aim of this study is to identify a biomarker or druggable target to enhance the effectiveness of radiotherapy on oral cancer patients. By performing an in silico analysis against public databases, we found that the upregulation of FOXD1, a gene encoding forkhead box d1 (Foxd1), is extensively detected in primary tumors compared to normal tissues and associated with a poor outcome in oral cancer patients receiving irradiation treatment. Moreover, our data showed that the level of FOXD1 transcript is causally relevant to the effective dosage of irradiation in a panel of oral cancer cell lines. The FOXD1 knockdown (FOXD1-KD) dramatically suppressed the colony-forming ability of oral cancer cells after irradiation treatment. Differentially expressed genes analysis showed that G3BP2, a negative regulator of p53, is predominantly repressed after FOXD1-KD and transcriptionally regulated by Foxd1, as judged by a luciferase-based promoter assay in oral cancer cells. Gene set enrichment analysis significantly predicted the inhibition of E2F-related signaling pathway but the activation of the interferons (IFNs) and p53-associated cellular functions, which were further validated by luciferase reporter assays in the FOXD1-KD oral cancer cells. Robustly, our data showed that FOXD1-KD fosters the expression of TXNIP, a downstream effector of IFN signaling and activator of p53, in oral cancer cells. These findings suggest that FOXD1 targeting might potentiate the anti-cancer effectiveness of radiotherapy and promote immune surveillance on oral cancer.

B-MYB-p53-related relevant regulator for the progression of clear cell renal cell carcinoma

PURPOSE

To investigate the mRNA expression of B-MYB and MDM2 together with their p53 relatedness in clear cell renal cell carcinoma (ccRCC).

METHODS

Genes were screened for their mRNA expression from 529 patients in a publicly available ccRCC cohort (TCGA). A cohort of 101 patients with ccRCC served as validation by qRT-PCR mRNA tissue expression analysis.

RESULTS

Expression: B-MYB expression was significantly higher in high-grade tumours (p < 0.0001 and p = 0.048) and in advanced stages (p = 0.005 and p = 0.037) in both cohorts. Correlation: p53-B-MYB as well as MDM2-B-MYB showed significant correlations in local and low-grade ccRCCs, but not in high grade tumours or advanced stages (r < 0.3 and/or p > 0.05). Survival: Multivariable Cox regression of the TCGA cohort revealed B-MYB upregulation and low MDM2 expression as predictors for an impaired overall survival (OS) (HR 1.97; p = 0.0003; HR 2.94, p < 0.0001) and progression-free survival (PFS) (HR 2.86; p = 0.0005; HR 1.58, p = 0.046). In the validation cohort, the results were confirmed for OS by univariable, but not multivariable regression: high B-MYB expression (HR = 3.05, p = 0.035) and low MDM2 expression (HR 3.81, p value 0.036).

CONCLUSION

In ccRCC patients with high-grade tumours and advanced stages, high B-MYB expression is common and is associated with poorer OS and PFS. These patients show a loss of their physiological B-MYB-p53 network correlation, suggesting an additional, alternative regulatory, oncogenic mechanism. Assuming further characterization of its signalling pathways, B-MYB could be a potential therapy target for ccRCC.

Analysis of the expression and association of retinoblastoma binding protein 6 with the JNK signaling pathway in prostate cancers

This study aims to investigate the expression of retinoblastoma binding protein 6 (RBBP6) in prostate cancer (PCa) and its association with the c-Jun N-terminal kinase (JNK) pathway. Immunohistochemistry was used to detect RBBP6 and JNK1/2 expression in PCa and benign prostatic hyperplasia tissues. RBBP6 expression in PCa cells (LNCap, PC3, and DU145) and noncancerous prostate epithelial cells (RWPE-1) was determined by quantitative real-time polymerase chain reaction and western blot analysis. PC3 and DU145 cells were transfected with RBBP6 small interfering RNAs (siRNAs) to examine the biological characteristics. Anisomycin (a JNK activator) with/without RBBP6 siRNA was used to treat PC3 cells for further investigating the ramification of the RBBP6-mediated JNK pathway in PCa. PCa tissues and cells showed higher RBBP6 and JNK1/2 expression. RBBP6 was positively correlated with JNK1/2 in PCa tissues. Besides, RBBP6 expression was correlated to clinical tumor stage, lymph node metastasis, Gleason grade, preoperative prostate-specific antigen level, as well as prognosis of PCa. RBBP6 siRNA reduced cell proliferation, arrested cells at G2/M, and promoted cell apoptosis, and suppressed JNK pathway. In addition, migration and invasion decreased after the RBBP6 siRNA transfection with downregulated matrix metallopeptidase-2 (MMP-2) and MMP-9. Anisomycin promoted the proliferation, invasion, and migration of PC3 cells and inhibited PC3 cell apoptosis, which could be reversed by RBBP6 siRNA. RBBP6 expression was upregulated in PCa tissues and positively correlated with expression level of JNK1/2. With inhibition of RBBP6 expression, the proliferation, invasion, and migration of PCa cells decreased dramatically, while PC3 cell apoptosis increased appreciably, accompanied by the suppression of the JNK pathway.