Canonical AREs are tumor suppressive regulatory elements in the prostate.

The androgen receptor (AR) is the central determinant of prostate tissue identity and differentiation, controlling normal, growth-suppressive prostate-specific gene expression 1 . It is also a key driver of prostate tumorigenesis, becoming "hijacked" to drive oncogenic transcription 2-5 . However, the regulatory elements determining the execution of the growth suppressive AR transcriptional program, and whether this can be reactivated in prostate cancer (PCa) cells remains unclear. Canonical androgen response element (ARE) motifs are the classic DNA binding element for AR 6 . Here, we used a genome-wide strategy to modulate regulatory elements containing AREs to define distinct AR transcriptional programs. We find that activation of these AREs is specifically associated with differentiation and growth suppressive transcription, and this can be reactivated to cause death in AR + PCa cells. In contrast, repression of AREs is well tolerated by PCa cells, but deleterious to normal prostate cells. Finally, gene expression signatures driven by ARE activity are associated with improved prognosis and luminal phenotypes in human PCa patients. This study demonstrates that canonical AREs are responsible for a normal, growth-suppressive, lineage-specific transcriptional program, that this can be reengaged in PCa cells for potential therapeutic benefit, and genes controlled by this mechanism are clinically relevant in human PCa patients.

Post-transcriptional modification of m6A methylase METTL3 regulates ERK-induced androgen-deprived treatment resistance prostate cancer.

As the most common modification of RNA, N6-methyladenosin (m6A) has been confirmed to be involved in the occurrence and development of various cancers. However, the relationship between m6A and castration resistance prostate cancer (CRPC), has not been fully studied. By m6A-sequencing of patient cancer tissues, we identified that the overall level of m6A in CRPC was up-regulated than castration sensitive prostate cancer (CSPC). Based on the analysis of m6A-sequencing data, we found m6A modification level of HRas proto-oncogene, GTPase (HRAS) and mitogen-activated protein kinase kinase 2 (MEK2 or MAP2K2) were enhanced in CRPC. Specifically, tissue microarray analysis and molecular biology experiments confirmed that METTL3, an m6A "writer" up-regulated after castration, activated the ERK pathway to contribute to malignant phenotype including ADT resistance, cell proliferation and invasion. We revealed that METTL3-mediated ERK phosphorylation by stabilizing the transcription of HRAS and positively regulating the translation of MEK2. In the Enzalutamide-resistant (Enz-R) C4-2 and LNCap cell line (C4-2R, LNCapR) established in the current study, the ERK pathway was confirmed to be regulated by METTL3. We also found that applying antisense oligonucleotides (ASOs) to target the METTL3/ERK axis can restore Enzalutamide resistance in vitro and in vivo. In conclusion, METTL3 activated the ERK pathway and induced the resistance to Enzalutamide by regulating the m6A level of critical gene transcription in the ERK pathway.

HOXB3 drives WNT-activation associated progression in castration-resistant prostate cancer.

Enabled resistance or innate insensitiveness to antiandrogen are lethal for castration-resistant prostate cancer (CRPC). Unfortunately, there seems to be little can be done to overcome the antiandrogen resistance because of the largely unknown mechanisms. In prospective cohort study, we found that HOXB3 protein level was an independent risk factor of PSA progression and death in patients with metastatic CRPC. In vivo, upregulated HOXB3 contributed to CRPC xenografts progression and abiraterone resistance. To uncover the mechanism of HOXB3 driving tumor progression, we performed RNA-sequencing in HOXB3 negative (HOXB3-) and HOXB3 high (HOXB3 + ) staining CRPC tumors and determined that HOXB3 activation was associated with the expression of WNT3A and enriched WNT pathway genes. Furthermore, extra WNT3A and APC deficiency led HOXB3 to be isolated from destruction-complex, translocated to nuclei, and then transcriptionally regulated multiple WNT pathway genes. What's more, we also observed that the suppression of HOXB3 could reduce cell proliferation in APC-downregulated CRPC cells and sensitize APC-deficient CRPC xenografts to abiraterone again. Together, our data indicated that HOXB3 served as a downstream transcription factor of WNT pathway and defined a subgroup of CRPC resistant to antiandrogen which would benefit from HOXB3-targeted therapy.

Androgen deprivation restores ARHGEF2 to promote neuroendocrine differentiation of prostate cancer.

Androgen receptor (AR) plays an important role in the progression of prostate cancer and has been targeted by castration or AR-antagonists. The emergence of castration-resistant prostate cancer (CRPC) after androgen deprivation therapy (ADT) is inevitable. However, it is not entirely clear how ADT fails or how it causes resistance. Through analysis of RNA-seq data, we nominate ARHGEF2 as a pivotal androgen-repressed gene. We show that ARHGEF2 is directly suppressed by androgen/AR. AR occupies the enhancer and communicates with the promoter region of ARHGEF2. Functionally, ARHGEF2 is important for the growth, lethal phenotype, and survival of CRPC cells and tumor xenografts. Correspondingly, AR inhibition or AR antagonist treatment can restore ARHGEF2 expression, thereby allowing prostate cancer cells to induce treatment resistance and tolerance. Overall, our findings provide an explanation for the contradictory clinical results that ADT resistance may be caused by the up-regulation of ARHGEF2 and provide a novel target.

Severe skin and subcutaneous pythiosis in China: Metagenomic identification and characterization of Pythium insidiosum.

Pythium insidiosum is a rare fungus-like pathogen that is known to cause pythiosis in mammals with high morbidity and mortality. Identification of the pathogen is essential for timely treatment and rational use of antibiotics. However, Pythium insidiosum is difficult to detect via conventional microbiological tests. The current gold standard is polymerase chain reaction, which is lacking in most hospitals since human pythiosis is rare in China. In this study, we used metagenomic Next-Generation Sequencing and identified Pythium insidiosum in a 56-year-old Chinese male who was hospitalized due to severe edema in the right lower limb with scattered darkening indurations. The patient had a history of cirrhosis and occupational exposure to swamp water. Serological level of immune biomarkers indicated immunodeficiency, and Proteinase 3-Anti-Neutrophil Cytoplasmic Antibody was positive. Surgical incision of the lesions revealed radiating and reticular cutaneous ulcers. Microbial infections were suspected but conventional tests failed to discover the etiology. Empirical use of penicillin, vancomycin, and ceftriaxone had no effect. As a result, the peripheral blood and tissue biopsies were sent for metagenomic Next-Generation Sequencing, which reported Pythium insidiosum. This finding was corroborated by pathological staining, whole-genome sequencing, and internal transcribed spacer sequencing. Notably, antifungal treatment was ineffective, but the patient responded well to oral trimethoprim-sulfamethoxazole, which may be due to the folp gene found in Pythium insidiosum genome. Our study prompts future studies to determine the optimal treatment of skin pythiosis.

hsa_circ_0092339 acts as a molecular sponge in castration-resistant prostate cancer via the hsa-mir-940/C-MYC axis.

Aims: We aimed to determine whether intronic circRNA acts as a molecular sponge in castration-resistant prostate cancer (CRPC). Materials & methods: A gene chip technique was used to conduct sequencing. A qPCR experiment was performed to verify the result. Radioimmunoprecipitation, RNA pull-down and dual-luciferase reporter assays were performed to particularly expound its function. Verification of downstream effects was carried out through qPCR and western blot, and a xenograft assay was performed in vivo for verification. Results: Intronic circRNA hsa_circ_0092339 in the nucleus was highly expressed in CRPC cell lines. hsa_circ_0092339 did not regulate the expression of its parental gene. hsa_circ_0092339 functions like a molecular sponge, preventing degradation of C-MYC mRNA by absorbing hsa-mir-940. Conclusion: hsa_circ_0092339 plays a critical role in CRPC through targeting C-MYC indirectly by absorbing hsa-mir-940.

Our research breaks the mold by investigating a novel function of RNA and a novel regulatory mechanism. Our research provides a new therapeutic target for prostate cancer treatment and broadens the understanding of prostate cancer.

The cell cycle gene centromere protein K (CENPK) contributes to the malignant progression and prognosis of prostate cancer.

Background: The cell cycle gene centromere protein K (CENPK) is upregulated in various cancers; however, the clinical value and mechanism of CENPK in prostate cancer (PCa) and castration-resistant prostate cancer (CRPC) remain unclear. Methods: The expression of CENPK in PCa was analyzed in both patients with PCa and cell lines using immunohistochemistry (IHC), real-time quantitative reverse transcription PCR (qRT-PCR), Western blot and bioinformatics analyses. Knockdown of CENPK in PCa cells was achieved by transfecting siRNAs and assessed using qRT-PCR and Western blotting. MTT and colony formation assays were used to assess the growth of PCa cells. The cell cycle was analyzed using propidium iodide (PI) staining and flow cytometry. To study the possible biological function of CENPK, pathway enrichment analysis was performed by dividing these groups into a high CENPK expression group and a low CENPK expression group based on the median CENPK expression level. Finally, the correlation between CENPK expression in PCa and clinical parameters was evaluated. Results: Our study revealed that CENPK was expressed at high levels in CRPC tissues and cell lines compared to primary PCa. The downregulation of CENPK significantly inhibited cell viability and reduced the number of colonies formed by LNCaP-AI and DU145 cells (two CRPC cell lines). Gene enrichment and flow cytometry analyses showed that high CENPK expression was linked to mitotic spindles and the cell cycle and may be involved in mitosis in the cell cycle of cancer cells to modulate cell proliferation and promote the development of CRPC. Moreover, patients exhibiting higher expression of the CENPK mRNA experienced shorter disease-free survival (DFS) and overall survival (OS) than the lower expression group. Conclusions: This study provides novel molecular insights into the role of CENPK in castration-resistant PCa cells and reveals that an increase in CENPK expression may indicate shorter DFS and a poor prognosis for patients with PCa. Targeting CENPK may be a novel strategy for the treatment of PCa.

N6-Methyladenosine dynamic changes and differential methylation in wheat grain development.

MAIN CONCLUSION: More methylation changes occur in late interval than in early interval of wheat seed development with protein and the starch synthesis-related pathway enriched in the later stages. Wheat seed development is a critical process to determining wheat yield and quality, which is controlled by genetics, epigenetics and environments. The N6-methyladenosine (m6A) modification is a reversible and dynamic process and plays regulatory role in plant development and stress responses. To better understand the role of m6A in wheat grain development, we characterized the m6A modification at 10 day post-anthesis (DPA), 20 DPA and 30 DPA in wheat grain development. m6A-seq identified 30,615, 30,326, 27,676 high confidence m6A peaks from the 10DPA, 20DPA, and 30DPA, respectively, and enriched at 3'UTR. There were 29,964, 29,542 and 26,834 unique peaks identified in AN0942_10d, AN0942_20d and AN0942_30d. One hundred and forty-two genes were methylated by m6A throughout seed development, 940 genes methylated in early grain development (AN0942_20d vs AN0942_10d), 1542 genes in late grain development (AN0942_30d vs AN0942_20d), and 1190 genes between early and late development stage (AN0942_30d vs AN0942_10d). KEGG enrichment analysis found that protein-related pathways and the starch synthesis-related pathway were significantly enriched in the later stages of seed development. Our results provide novel knowledge on m6A dynamic changes and its roles in wheat grain development.

A Semiconductive Nature of Bis(dithiolato)nickelate Radical Salt Exhibiting Broadband Photoconduction.

The fractional oxidation state [M(dmit)2] (dmit2- = 2-thioxo-1, 3-dithiole-4, 5-dithiolate) salts have long attracted attention in the molecular metal area owing to high conductivity and even superconductivity. In this study, we achieved a mixed-valence salt (1) of [Ni(dmit)2]0.5- with monovalent 1,3-N,N-dimethyl-imidazolium (DiMIm+) by a solvent evaporation approach under ambient conditions. The mixed valence of [Ni(dmit)2]0.5- has been characterized by an analysis of the IR spectrum and crystal structure. In the crystal structure of 1, two [Ni(dmit)2]0.5- anions overlap in an eclipsed mode to form a [Ni(dmit)2]21- dimer, featuring a radical bearing an S = 1/2 spin; the dimeric radicals stack into a column along the b axis, and the adjacent columns connect together via the lateral-to-lateral S···S contacts along the a axis, and through the head-to-head S···S contacts along the [101] direction. Salt 1 shows the magnetic behavior of an S = 1/2 Heisenberg antiferromagnetic uniform linear chain with J/kB = -47.5(4) K and a semiconducting feature with σ = 2.52 × 10-3 S cm-1 at 293 K, 2.32 × 10-2 S cm-1 at 373 K, and Ea = 0.22 eV, as well as broadband photoconductivity under irradiation of green and white lights. This study suggests the possibility of designing new photoconductors based on the mixed-valence [Ni(dmit)2]0.5- salt.

A narrative review of proteolytic targeting chimeras (PROTACs): future perspective for prostate cancer therapy.

Proteolysis-TArgeting Chimeras (PROTACs) technology, as a strategy to chemically knock down transcription factors at the protein levels, can hijack the ubiquitin-proteasome degradation system to initiate the intracellular ubiquitin-proteasome hydrolysis process to degrade proteins. In the past, the development of drugs that target transcription factors has been greatly restricted, and even historically transcription factors have been regarded as "undruggable targets". PROTAC technology breaks through this limitation with its unique targeting design. With several generations of technical innovation, PROTACs have become more mature and continue to make breakthroughs in the field of targeted therapy including prostate cancer (PCa), with a new strategy for the development of anti-tumor targeted drugs. PROTACs have all the advantages of existing small molecule inhibitors, are easy to administer orally, have good cell permeability, and have wider targeting profiles compared to conventional inhibitors. The disadvantage of PROTACs is the noncancer specificity, off-target and sustained-release control, due to its catalytic role. Some androgen receptor (AR) and CDK4/6 degraders have advanced the field of PCa treatment, which is being further modified given the effects of these degraders in preclinical and clinical studies. This review summarizes in detail the technological progress and challenges that have been faced with PROTACs, the progress of research on PCa, and the prospective future of PROTACs development.

Increased expression of CELSR3 indicates a poor prognostic factor for Prostate Cancer.

Background: Cadherin EGF LAG Seven-Pass G-Type Receptor 3 (CELSR3) gene was reported to be overexpressed in various human cancers and involved in the regulation of neurite-dependent neurite outgrowth and may play a role in tumor formation. However, the clinical significance of CELSR3 in prostate cancer (PCa) has not been fully studied. Methods: The expression of CELSR3 was detected by crossover analysis of the public datasets and cell lines. MTT assay and migration assay were performed to evaluate the cells' physiological functioning. Co-expressed genes and enrichment analysis was performed to investigate the biological significance of CELSR3 in PCa. Quantitative real-time polymerase chain reaction was used to detect the expression levels of hub genes (CENPE, CENPA, CDC20, NUF2, ESPL1, PLK1) related to CELSR3. Results: We found a significant increase in CELSR3 expression in PCa patients and cell lines. Furthermore, immunohistochemical analysis showed that CELSR3 protein expression was significantly more highly expressed in the PCa tissues compared to the non-cancerous PCa tissues. CELSR3 downregulation significantly suppressed cell proliferation and migration potential. CELSR3-related hub genes (CENPE, CENPA, CDC20, NUF2, ESPL1, PLK1) were selected and the functions of these hub genes showed that the function of CELSR3 was closely related to the cell cycle-related signaling pathways. The upregulation of CELSR3 mRNA expression in the PCa tissues significantly correlated with the presence of high serum PSA levels, high pathological stage, high Gleason score, short overall survival time and short disease-free survival time. Conclusion: Our data suggest that CELSR3 may play an important role in the progression of PCa. More importantly, an increase in CELSR3 expression may be indicative of poor disease-free survival and poor prognosis in PCa patients.

Rod-like MnO2 boost Pd/reduced graphene oxide nanocatalyst for ethylene glycol electrooxidation.

Anode catalyst is one of the core components of fuel cell, but its poor catalytic activity, short lifespan, and high price are tricky problems to the commercialization of fuel cell. Herein, a novel rod-like MnO2 decorated reduced graphene oxide (RGO) supported Pd hybrid (Pd/RGO-MnO2) has been designed, which manifests more negative onset oxidation potential, higher peak current density, and better long-term stability relative to Pd/RGO and pure Pd catalysts when serving for ethylene glycol electrooxidation. This enhancement may be due to the addition of MnO2, which can effectively promote the adsorption of hydroxyl at a lower potential and produce a strong electronic interaction with Pd, as confirmed by X-ray photoelectron spectroscopy (XPS) technique. In view of its excellent performance and low cost, Pd/RGO-MnO2 is considered to be a potential and effective anode catalyst for DEGFCs.

Downregulation of LOX promotes castration-resistant prostate cancer progression via IGFBP3.

The role of lysyl oxidase (LOX) in prostate cancer remains controversial. Studies have shown that LOX may inhibit the progression of prostate cancer (PCa), whereas other studies demonstrate that LOX may act as a tumor activator in PCa. Here, we report that low LOX expression contributes to CRPC progression through upregulation of IGFBP3. We showed that LOX expression decreased in the more advanced and aggressive castration-resistant prostate cancer (CRPC), compared to castration-sensitive prostate cancer (CSPC). We demonstrated that LOX was negatively correlated with IGFBP3 and may directly bind to the promoter of IGFBP3 and thus decrease the expression of IGFBP3. Inhibition of IGFBP3 by siRNA suppressed the growth and migration of CRPC cells, suggesting a critical role for IGFBP3 in CRPC. The preclinical study in a mouse model suggested that introducing back LOX inhibited the progression of CRPC. In summary, we identified a new function of LOX in PCa and discovered that LOX downregulation contributed to progression via IGFBP3, and that the restoration of LOX may be a promising therapeutic strategy for PCa.

Super-enhancer in prostate cancer: transcriptional disorders and therapeutic targets.

Abnormal activity of oncogenic and tumor-suppressor signaling pathways contributes to cancer and cancer risk in humans. Transcriptional dysregulation of these pathways is commonly associated with tumorigenesis and the development of cancer. Genetic and epigenetic alterations may mediate dysregulated transcriptional activity. One of the most important epigenetic alternations is the non-coding regulatory element, which includes both enhancers and super-enhancers (SEs). SEs, characterized as large clusters of enhancers with aberrant high levels of transcription factor binding, have been considered as key drivers of gene expression in controlling and maintaining cancer cell identity. In cancer cells, oncogenes acquire SEs and the cancer phenotype relies on these abnormal transcription programs driven by SEs, which leads to cancer cells often becoming addicted to the SEs-related transcription programs, including prostate cancer. Here, we summarize recent findings of SEs and SEs-related gene regulation in prostate cancer and review the potential pharmacological inhibitors in basic research and clinical trials.

YAP1 plays a key role of the conversion of normal fibroblasts into cancer-associated fibroblasts that contribute to prostate cancer progression.

BACKGROUND: Cancer-associated fibroblasts (CAFs) are an important part of the tumour microenvironment, and their functions are of great concern. This series of experiments aimed to explore how Yes-associated protein 1 (YAP1) regulates the function of stromal cells and how the normal fibroblasts (NFs) convert into CAFs in prostate cancer (PCa). METHODS: The effects of conditioned media from different fibroblasts on the proliferation and invasion of epithelial cells TrampC1 were examined. We then analysed the interaction between the YAP1/TEAD1 protein complex and SRC, as well as the regulatory function of the downstream cytoskeletal proteins and actins. A transplanted tumour model was used to explore the function of YAP1 in regulating tumour growth through stromal cells. The relationship between the expression of YAP1 in tumour stromal cells and the clinical characteristics of PCa patients was analysed. RESULTS: The expression level of YAP1 was significantly upregulated in PCa stromal cells. After the expression level of YAP1 was increased, NF was transformed into CAF, enhancing the proliferation and invasion ability of epithelial cells. The YAP1/TEAD1 protein complex had the capability to influence downstream cytoskeletal proteins by regulating SRC transcription; therefore, it converts NF to CAF, and CAF can significantly promote tumour growth and metastasis. The high expression of YAP1 in the tumour stromal cells suggested a poor tumour stage and prognosis in PCa patients. CONCLUSION: YAP1 can convert NFs into CAFs in the tumour microenvironment of PCa, thus promoting the development and metastasis of PCa. Silencing YAP1 in tumour stromal cells can effectively inhibit tumour growth.

Metal-Free Organic Optoelectronic Molecule as a Highly Efficient Photocatalyst for the Degradation of Organic Pollutants.

With the increasing consumption of natural resources, photocatalysis converting solar energy to chemical energy has attracted extensive attention of researchers owing to the advantages of developing energy-saving and environmentally benign processes. In this work, a facile and simple method was developed to synthesize a metal-free organic optoelectronic molecule (denoted as DPPRD), which is composed of a central diketopyrrolopyrrole moiety and two terminal units of a rhodanine (RD) moiety. This is a first green strategy toward the synthesis of DPPRD. Because of good thermal stability, narrow band gap, and excellent visible light absorption of solar spectrum, DPPRD exhibited to be an efficient and chemically stable photocatalyst for visible light degradation of organic pollutants such as bisphenol A (BPA) and methyl orange (MO) in aqueous solution. The control experiments with different types of radical scavengers implied that the hole (h+) and hydroxyl radicals (•OH) were the key reactive species during the photodegradation processes. The photodegradation pathways of BPA and MO were thus proposed based on the identified intermediates. This improved method for DPPRD synthesis is expected to widen its applications to industrial production, whereas its excellent visible light photocatalytic activity would be utilized potentially in the field of environmental and industrial applications.

Correction: Neurotensin and its receptors mediate neuroendocrine transdifferentiation in prostate cancer.

A correction to this paper has been published and can be accessed via a link at the top of the paper.

Androgen deprivation therapy with chemotherapy or abiraterone for patients with metastatic hormone-naive prostate cancer: a systematic review and meta-analysis.

Patients with metastasis prostate cancer underwent androgen deprivation therapy (ADT) in the considering of the leading role of androgen receptor pathway. However, the resistance occurred within 1 year or more. The combination of cytotoxic chemotherapy and abiraterone for ADT therapy was performed in recent randomized controlled trials. The meta-analysis was focused on the treatment comparisons between additional treatment with ADT and ADT alone. A significant difference was observed that the overall survival benefit of early and active additional treatment with ADT in patients with hormone-sensitive metastatic prostate cancer. However, a great proportion of patients with metastatic disease have metastases after receiving ADT. It will be important to further improve the treatment options.

Neurotensin and its receptors mediate neuroendocrine transdifferentiation in prostate cancer.

Castration-resistant prostate cancer (CRPC) with neuroendocrine differentiation (NED) is a lethal disease for which effective therapies are urgently needed. The mechanism underlying development of CRPC with NED, however, remains largely uncharacterized. In this study, we explored and characterized the functional role of neurotensin (NTS) in cell line and animal models of CRPC with NED. NTS was acutely induced by androgen deprivation in animal models of prostate cancer (PCa) and activated downstream signaling leading to NED through activation of neurotensin receptor 1 (NTSR1) and neurotensin receptor 3 (NTSR3), but not neurotensin receptor 2 (NTSR2). Our findings also revealed the existence of a CK8+/CK14+ subpopulation in the LNCaP cell line that expresses high levels of both NTSR1 and NTSR3, and displays an enhanced susceptibility to develop neuroendocrine-like phenotypes upon treatment with NTS. More importantly, NTSR1 pathway inhibition prevented the development of NED and castration resistance in vivo. We propose a novel role of NTS in the development of CRPC with NED, and a possible strategy to prevent the onset of NED by targeting the NTS signaling pathway.