Allosteric inhibition of HSP70 in collaboration with STUB1 augments enzalutamide efficacy in antiandrogen resistant prostate tumor and patient-derived models.

Ubiquitin proteasome activity is suppressed in enzalutamide resistant prostate cancer cells, and the heat shock protein 70/STIP1 homology and U-box-containing protein 1 (HSP70/STUB1) machinery are involved in androgen receptor (AR) and AR variant protein stabilization. Targeting HSP70 could be a viable strategy to overcome resistance to androgen receptor signaling inhibitor (ARSI) in advanced prostate cancer. Here, we showed that a novel HSP70 allosteric inhibitor, JG98, significantly suppressed drug-resistant C4-2B MDVR and CWR22Rv1 cell growth, and enhanced enzalutamide treatment. JG98 also suppressed cell growth in conditional reprogramed cell cultures (CRCs) and organoids derived from advanced prostate cancer patient samples. Mechanistically, JG98 degraded AR/AR-V7 expression in resistant cells and promoted STUB1 nuclear translocation to bind AR-V7. Knockdown of the E3 ligase STUB1 significantly diminished the anticancer effects and partially restored AR-V7 inhibitory effects of JG98. JG231, a more potent analog developed from JG98, effectively suppressed the growth of the drug-resistant prostate cancer cells, CRCs, and organoids. Notably, the combination of JG231 and enzalutamide synergistically inhibited AR/AR-V7 expression and suppressed CWR22Rv1 xenograft tumor growth. Inhibition of HSP70 using novel small-molecule inhibitors coordinates with STUB1 to regulate AR/AR-V7 protein stabilization and ARSI resistance.

Systematic analyzing a five- miRNA panel and its diagnostic value of plasma expression in colorectal cancer.

BACKGROUND: Aberrant expression of miRNAs have been implicated in cancers, but the role of miRNAs in colorectal cancer (CRC) remains need to be elucidated. This study aimed to identify miRNAs that related to colorectal cancer (CRC) pathogenesis and determine the diagnostic value. METHODS: Three GEO datasets (GSE128449, GSE35602 and GSE49246) with 131 samples were used to screen miRNAs that differential expression between tumor and control tissues. The expression of the identified miRNAs was validated in 50 clinical tissue samples and the GSE35834 dataset. The clinical significance of these miRNAs was analyzed in the TCGA dataset and clinical tissue samples. The expression of miRNAs in tissues and plasma samples were tested by RT-PCR assay in clinical samples, and their diagnostic value was determined. RESULTS: The analysis of three GEO datasets revealed that miR-595 and miR-1237 were upregulated, while miR-126, miR-139, and miR-143 were downregulated in CRC tissues compared to control tissues. The differential expression of the five miRNAs in CRC tissues was confirmed using clinical tissue samples and GEO databases. There was no significant correlation between the TNM stage and tumor stage of CRC and any of the five miRNAs. Plasma expression of the miRNAs differed significantly between CRC and non-cancer patients, and each miRNA had moderate diagnostic value for CRC. Combining the five miRNAs provided better diagnostic potential for CRC than a single miRNA. CONCLUSIONS: This study demonstrated that five miRNAs were related to the pathogenesis of CRC, but independent of the stage of CRC; Plasma expression of these miRNAs have moderate diagnostic value, and combination of these miRNAs showed better diagnostic ability in CRC.

A follow-up study in children with status epilepticus during sleep: From clinical spectrum to outcome.

PURPOSE: To evaluate the correlation between clinical spectrum and therapeutic outcomes and neuropsychological deficits in children with status epilepticus during sleep (SES). METHODS: The clinical spectrum of patients with SES was defined as follows: status epilepticus of benign childhood epilepsy with centro-temporal spikes (SEBECTs), atypical benign focal epilepsy during childhood (ABFEC), non-idiopathic focal epilepsy (NIFE), and Landau-Kleffner syndrome (LKS). SES cases were divided into 4 groups according to neuropsychological findings before treatment: developmental delay/intellectual disability (DD/ID), cognitive impairment (CI), attention deficit and/or hyperactivity behaviors (AHD), and normal group (NG). The therapeutic outcomes were classified into 3 groups: satisfactory response, recurrence, and seizure control. RESULTS: A total of 39 cases (24 males and 15 females) were recruited, including 3 cases with SEBECTs, 26 with ABFEC, 8 with NIFE [2 with focal cortical dysplasia (FCD)], and 2 with LKS. There were 7 patients in the DD/ID group, 8 in the CI group, 19 in the AHD group, and 5 in the NG group. Neuropsychological outcomes were significantly different among clinical spectrum (P < 0.001), and neuropsychological deficits frequently occurred in the ABFEC group or in the NIFE group. Besides, 18 patients in the satisfactory group had satisfactory response to medicine or surgery (2 out of 18 cases with FCD), whereas recurrence was observed at least one session within one year in 16 cases in the recurrence group, and no improvement in spike-wave index and cognition/behavior was noted in 5 patients in the seizure control group, although seizure could be controlled. There were significant differences in therapeutic outcomes among clinical spectrum (P = 0.041), with the worst outcomes in the NIFE group (only 1 out of 8 with satisfactory good response). CONCLUSIONS: It is important to categorize patients with SES into epilepsy syndromes, including SEBECTs, ABFPEC, NIFE, and LKS; the clinical spectrum may be a significant determinant to influence the outcomes of SES, including neuropsychological deficits and therapeutic outcomes.

[Bioinformation analysis of chorismate synthase in Baphicacantus cusia and other 78 species of plants].

Chorismate synthase(CS, EC:4.2.3.5) catalyses 5-enolpyruvy-shikimate-3-phosphate to form chorismate, which is the essential enzyme for chorismate biosynthesis in organisms. The amino acid sequences of CS from 79 species of higher plants were reported in GenBank at present. 125 amino acid sequences of CS from Baphicacanthus cusia and other 78 species of plants were predicted and analyzed by using various bioinformatics software, including the composition of amino acid sequences, signal peptide, leader peptide, hydrophobic/hydrophilic, transmembrane structure, coiled-coil domain, protein secondary structure, tertiary structure and functional domains. The phylogenetic tree of CS protein family was constructed and divided into eight groups by phylogenetic analysis. The homology comparison indicated that B. cusia shared a high homology with several plants such as Sesamum indicum, Nicotiana tabacum, Solanum tuberosum and so on. The open reading frame(ORF) of all samples is about 1 300 bp, the molecular weight is about 50 kDa, the isoelectric point(pI) is 5.0-8.0 which illustrated that CS protein is slightly basic. The ORF of CS we cloned in B. cusia is 1 326 bp, the amino acid residues are 442, the molecular weight is 47 kDa and pI is 8.11. The CS in B.cusia showed obvious hydrophobicity area and hydrophilicity area, no signal peptide, and may exists transmembrane structure areas. The main secondary structures of CS protein are random coil and Alpha helix, also contain three main structural domains which are an active structural domain, a PLN02754 conserved domain and a FMN binding site. The acquired information in this study would provide certain scientific basis for further study on structure-activity relationship and structure modification of CS in plants in the future.

Crystal Structures, Stabilities, Electronic Properties, and Hardness of MoB2: First-Principles Calculations.

On the basis of the first-principles techniques, we perform the structure prediction for MoB2. Accordingly, a new ground-state crystal structure WB2 (P63/mmc, 2 fu/cell) is uncovered. The experimental synthesized rhombohedral R3̅m and hexagonal AlB2, as well as theoretical predicted RuB2 structures, are no longer the most favorite structures. By analyzing the elastic constants, formation enthalpies, and phonon dispersion, we find that the WB2 phase is thermodynamically and mechanically stable. The high bulk modulus B, shear modulus G, low Poisson's ratio ν, and small B/G ratio are benefit to its low compressibility. When the pressure is 10 GPa, a phase transition is observed between the WB2-MoB2 and the rhombohedral R3̅m MoB2 phases. By analyzing the density of states and electron density, we find that the strong covalent is formed in MoB2 compounds, which contributes a great deal to its low compressibility. Furthermore, the low compressibility is also correlated with the local buckled structure.

Investigating the differences between receptor and dispersion modeling for concentration prediction and health risk assessment of volatile organic compounds from petrochemical industrial complexes.

Receptor and dispersion models both provide important information to help understand the emissions of volatile organic compounds (VOCs) and develop effective management strategies. In this study, differences between the predicted concentrations of two models and the associated impacts on the estimated health risks due to different theories behind two models were investigated. Two petrochemical industrial complexes in Kaohsiung city of southern Taiwan were selected as the sites for this comparison. Although the study compares the approaches by applying the methods to this specific area, the results are expected to be adopted for other areas or industries. Ninety-nine VOC concentrations at eight monitoring sites were analyzed, with the effects of diurnal temperature and seasonal humidity variations being considered. The Chemical Mass Balance (CMB) receptor model was used for source apportionment, while the Industrial Source Complex (ISC) dispersion model was used to predict the VOC concentrations at receptor sites. In the results of receptor modeling, 54% ± 11% and 49% ± 20% of the monitored concentrations were contributed by process emissions in two complexes, whereas the numbers increased to 78% ± 41% and 64% ± 44% in the results of dispersion modeling. Significant differences were observed between two model predictions (p < 0.05). The receptor model was more reproducible given the smaller variances of its results. The effect of seasonal humidity variation on two model predictions was not negligible. Similar findings were observed given that the cancer and non-cancer risks estimated by the receptor model were lower but more reproducible. The adverse health risks estimated by the dispersion model exceeded and were 75.3%-132.4% of the values estimated by using the monitored data, whereas the percentages were lowered to the range from 27.4% to 53.8% when the prediction was performed by using the receptor model. As the results of different models could be significantly different and affect the final health risk assessment, it is important to carefully choose an appropriate model for prediction and to evaluate by monitoring to avoid providing false information for appropriate management.

[Species Identification of Puparium Samples of Common Sarcosaphagous Flies Based on Molecular Marker Analysis].

OBJECTIVE: To investigate the application value of empty puparia in species identification of common sarcosaphagous flies. METHODS: Fifty-five samples of adult flies and their empty puparia were collected. All the samples were identified as 2 families, 6 genera and 8 species by morphological characteristics. The samples were divided into 3 groups according to their time period between eclosion and our analyses: less than 2 years (n = 23), 2-5 years (n = 20), and more than 5 years (n = 12). The mtDNA of each sample was extracted by CTAB method. The purity and concentration of DNA were tested. PCR products were amplified using two sets of primers. Two sequences of CO I gene (sequence I: 498 bp, sequence II : 841 bp) from each sample were compared to the sequences in GenBank using BLAST for species identification. RESULTS: The mtDNA was extracted successfully from all the samples. DNA concentration of adult chest muscle preserved less than or equal to 5 years and empty puparia preserved less than 2 years ranged from 1.0 to 3.0 µg/µl, and the value of A260/A280 ranged from 1.6 to 1.8. The purity and concentration was lower than 1.6 and 1.0 µg/µl, when the adult chest muscle and empty puparia preserved more than 5 years and 2 years, respectively. DNA concentration of the samples significantly decreased with the prolonged preservation time (P < 0.01). Two sequences of CO I gene was amplified in adult chest muscle and empty puparia which preserved less than 2 years. The success rates of amplification decreased with the prolonged preservation time, especially for the sequence II (P < 0.01). The morphological identification of 8 species did not match exactly with the results based on the COI gene, correct species identification occurred in 6 and 7 species out of 8 based on the two sequences, respectively, and their Max ident value exceeded 97% CONCLUSION: Empty puparium samples can be used to extract mtDNA and identify species.

Magnetic bead-based separation of sperm from buccal epithelial cells using a monoclonal antibody against MOSPD3.

Forensic DNA analysis of sexual assault evidence requires unambiguous differentiation of DNA profiles in mixed samples. To investigate the feasibility of magnetic bead-based separation of sperm from cell mixtures using a monoclonal antibody against MOSPD3 (motile sperm domain-containing protein 3), 30 cell samples were prepared by mixing 10(4) female buccal epithelial cells with sperm cells of varying densities (10(3), 10(4), or 10(5) cells/mL). Western blot and immunofluorescence assays showed that MOSPD3 was detectable on the membrane of sperm cells, but not in buccal epithelial cells. After biotinylated MOSPD3 antibody was incubated successively with the prepared cell mixtures and avidin-coated magnetic beads, microscopic observation revealed that each sperm cell was bound by two or more magnetic beads, in the head, neck, mid-piece, or flagellum. A full single-source short tandem repeat profile could be obtained in 80% of mixed samples containing 10(3) sperm cells/mL and in all samples containing ≥10(4) sperm cells/mL. For dried vaginal swab specimens, the rate of successful detection was 100% in both flocked and cotton swabs preserved for 1 day, 87.5% in flocked swabs and 40% in cotton swabs preserved for 3 days, and 40% in flocked swabs and 16.67% in cotton swabs preserved for 10 days. Our findings suggest that immunomagnetic bead-based separation is potentially a promising alternative to conventional methods for isolating sperm cells from mixed forensic samples.

Targeting DSS-induced ulcerative colitis: evaluating the therapeutic potential of WPI-stachyose conjugates.

The pursuit of food-based alternatives to conventional therapies for ulcerative colitis (UC) demands immediate attention. In prior investigations, we synthesized WPI-stachyose conjugates through the Maillard reaction, identifying them as functional prebiotics. However, their impact on in vivo regulation of gut microbiota remains inadequately explored. To bridge this gap, we delved into the therapeutic effects and mechanisms of WPI-stachyose conjugates as prebiotic-functional components in C57BL/6J mice afflicted with dextran sodium sulfate (DSS)-induced UC. The treatment involving WPI-stachyose conjugates led to significant therapeutic advancements, evident in the reduction of pro-inflammatory cytokine levels and restoration of gut microbiota composition. Noticeable enhancements were observed in UC-associated symptoms, including weight loss, colon length reduction, and tissue damage, notably improving in the treated mice. Remarkably, both the conjugates and the physical combination effectively lowered pro-inflammatory cytokines and oxidative stress, with the conjugates demonstrating enhanced effectiveness. Furthermore, the simultaneous administration of WPI-stachyose conjugates further amplified the presence of beneficial bacteria and elevated short-chain fatty acids, acknowledged for their favorable impact across various conditions. These findings underscore the potential therapeutic application of WPI-stachyose conjugates in addressing DSS-induced UC, offering insights into innovative therapeutic strategies.

Plexin D1 emerges as a novel target in the development of neural lineage plasticity in treatment-resistant prostate cancer.

Treatment-induced neuroendocrine prostate cancer (t-NEPC) often arises from adenocarcinoma via lineage plasticity in response to androgen receptor signaling inhibitors, such as enzalutamide. However, the specific regulators and targets involved in the transition to NEPC are not well understood. Plexin D1 (PLXND1) is a cellular receptor of the semaphorin (SEMA) family that plays important roles in modulating the cytoskeleton and cell adhesion. Here, we found that PLXND1 was highly expressed and positively correlated with neuroendocrine markers in patients with NEPC. High PLXND1 expression was associated with poorer prognosis in prostate cancer patients. Additionally, PLXND1 was upregulated and negatively regulated by androgen receptor signaling in enzalutamide-resistant cells. Knockdown or knockout of PLXND1 inhibited neural lineage pathways, thereby suppressing NEPC cell proliferation, patient derived xenograft (PDX) tumor organoid viability, and xenograft tumor growth. Mechanistically, the heat shock protein 70 (HSP70) regulated PLXND1 protein stability through degradation, and inhibition of HSP70 decreased PLXND1 expression and NEPC organoid growth. In summary, our findings indicate that PLXND1 could serve as a promising therapeutic target and molecular marker for NEPC.

Plexin D1 emerges as a novel target in the development of neural lineage plasticity in treatment-resistant prostate cancer.

Treatment-induced neuroendocrine prostate cancer (t-NEPC) often arises from adenocarcinoma via lineage plasticity in response to androgen receptor signaling inhibitors, such as enzalutamide. However, the specific regulators and targets involved in the transition to NEPC are not well understood. Plexin D1 (PLXND1) is a cellular receptor of the semaphorin (SEMA) family that plays important roles in modulating the cytoskeleton and cell adhesion. Here, we found that PLXND1 is highly expressed and positively correlated with neuroendocrine markers in patients with NEPC. High PLXND1 expression is associated with poorer prognosis in prostate cancer patients. Additionally, PLXND1 was upregulated and negatively regulated by androgen receptor signaling in enzalutamide-resistant cells. Knockdown or knockout of PLXND1 inhibit neural lineage pathways, suppressing NEPC cell proliferation, PDX tumor organoid viability, and xenograft tumor growth. Mechanistically, the chaperone protein HSP70 regulates PLXND1 protein stability through degradation, and inhibition of HSP70 decreases PLXND1 expression and NEPC organoid growth. In summary, our findings suggest that PLXND1 could be a new therapeutic target and molecular indicator for NEPC.

IGFBP3 promotes resistance to Olaparib via modulating EGFR signaling in advanced prostate cancer.

Olaparib is a pioneering PARP inhibitor (PARPi) approved for treating castration-resistant prostate cancer (CRPC) tumors harboring DNA repair defects, but clinical resistance has been documented. To study acquired resistance, we developed Olaparib-resistant (OlapR) cell lines through chronic Olaparib treatment of LNCaP and C4-2B cell lines. Here, we found that IGFBP3 is highly expressed in acquired (OlapR) and intrinsic (Rv1) models of Olaparib resistance. We show that IGFBP3 expression promotes Olaparib resistance by enhancing DNA repair capacity through activation of EGFR and DNA-PKcs. IGFBP3 depletion enhances efficacy of Olaparib by promoting DNA damage accumulation and subsequently, cell death in resistant models. Mechanistically, we show that silencing IGFBP3 or EGFR expression reduces cell viability and resensitizes OlapR cells to Olaparib treatment. Inhibition of EGFR by Gefitinib suppressed growth of OlapR cells and improved Olaparib sensitivity, thereby phenocopying IGFBP3 inhibition. Collectively, our results highlight IGFBP3 and EGFR as critical mediators of Olaparib resistance.

Methylation characteristics and developmental potential of Guangxi Bama minipig (Sus scrofa domestica) cloned embryos from donor cells treated with trichostatin A and 5-aza-2'-deoxycytidine.

Summary Reprogramming of DNA methylation in somatic cell nuclear transfer (SCNT) embryos is incomplete, and aberrant DNA methylation patterns are related to the inefficiency of SCNT. To facilitate nuclear reprogramming, this study investigated the effect of treating Guangxi Bama minipig donor cells with trichostatin A (TSA), 5-aza-2'-deoxycytine (5-aza-dC), or combination of TSA and 5-aza-dC prior to nuclear transfer. Analyses showed that there were no major changes in cell-cycle status among all groups. We monitored the transcription of DNMT1, DNMT3a, HDAC1 and IGF2 genes in donor cells. Transcription levels of HDAC1 were decreased significantly after treatment with a combination of TSA and 5-aza-dC, along with a significantly increased level of IGF2 (P < 0.05). Although treatment of donor cells with either TSA or 5-aza-dC alone resulted in non-significant effects in blastocyst formation rate and DNA methylation levels, a combination of TSA and 5-aza-dC significantly improved the development rates of minipig SCNT embryos to blastocyst (25.6% vs. 16.0%, P < 0.05). This change was accompanied by decreased levels of DNA methylation in somatic cells and blastocyst (P < 0.05). Thus in combination with TSA, lower concentrations of 5-aza-dC may produce a potent demethylating activity, and lead to the significantly enhanced blastocyst development percentage of Bama minipig SCNT embryos.

Therapeutic Resistance Models and Treatment Sequencing in Advanced Prostate Cancer.

Current common treatments for castration-resistant prostate cancer (CRPC) typically belong to one of three major categories: next-generation anti-androgen therapies (NGAT) including enzalutamide, abiraterone acetate, apalutamide, and darolutamide; taxane therapy represented by docetaxel; and PARP inhibitors (PARPi) like olaparib. Although these treatments have shown efficacy and have improved outcomes for many patients, some do not survive due to the emergence of therapeutic resistance. The clinical landscape is further complicated by limited knowledge about how the sequence of treatments impacts the development of therapeutic cross-resistance in CRPC. We have developed multiple CRPC models of acquired therapeutic resistance cell sublines from C4-2B cells. These include C4-2B MDVR, C4-2B AbiR, C4-2B ApaR, C4-2B DaroR, TaxR, and 2B-olapR, which are resistant to enzalutamide, abiraterone, apalutamide, darolutamide, docetaxel, and olaparib, respectively. These models are instrumental for analyzing gene expression and assessing responses to various treatments. Our findings reveal distinct cross-resistance characteristics among NGAT-resistant cell sublines. Specifically, resistance to enzalutamide induces resistance to abiraterone and vice versa, while maintaining sensitivity to taxanes and olaparib. Conversely, cells with acquired resistance to docetaxel exhibit cross-resistance to both cabazitaxel and olaparib but retain sensitivity to NGATs like enzalutamide and abiraterone. OlapR cells, significantly resistant to olaparib compared to parental cells, are still responsive to NGATs and docetaxel. Moreover, OlapR models display cross-resistance to other clinically relevant PARP inhibitors, including rucaparib, niraparib, and talazoparib. RNA-sequencing analyses have revealed a complex network of altered gene expressions that influence signaling pathways, energy metabolism, and apoptotic signaling, pivotal to cancer's evolution and progression. The data indicate that resistance mechanisms are distinct among different drug classes. Notably, NGAT-resistant sublines exhibited a significant downregulation of androgen-regulated genes, contrasting to the stable expression noted in olaparib and docetaxel-resistant sublines. These results may have clinical implications by showing that treatments of one class can be sequenced with those from another class, but caution should be taken when sequencing drugs of the same class.

Novel inhibition of AKR1C3 and androgen receptor axis by PTUPB synergizes enzalutamide treatment in advanced prostate cancer.

Castration-resistant prostate cancer (CRPC) is the main driving force of mortality in prostate cancer patients. Among the parameters contributing to the progression of CRPC and treatment failure, elevation of the steroidogenic enzyme AKR1C3 and androgen receptor variant 7 (AR-V7) are frequently reported. The AKR1C3/AR-V7 complex has been recognized as a major driver for drug resistance in advanced prostate cancer. Herein we report that the level of AKR1C3 is reciprocally regulated by the full-length androgen receptor (AR-FL) through binding to the distal enhancer region of the AKR1C3 gene. A novel function of PTUPB in AKR1C3 inhibition was discovered and PTUPB showed more effectiveness than indomethacin and celecoxib in suppressing AKR1C3 activity and CRPC cell growth. PTUPB synergizes with enzalutamide treatment in tumor suppression and gene signature regulation. Combination treatments with PTUPB and enzalutamide provide benefits by blocking AR/AR-V7 signaling, which inhibits the growth of castration relapsed VCaP xenograft tumors and patient-derived xenograft organoids. Targeting of the ARK1C3/AR/AR-V7 axis with PTUPB and enzalutamide may overcome drug resistance to AR signaling inhibitors in advanced prostate cancer.

[Effect of TSA and VPA treatment on long-tailed macaque (Macaca fascicularis)-pig interspecies somatic cell nuclear transfer].

Long-tailed macaque-pig interspecies somatic cell nuclear transfer (iSCNT) is beneficial to yield embryonic stem cells from iSCNT embryos with similar genetic background as human, which can be used as materials for medical and basic research. The primary objective of this study was to investigate the effects of concentrations and treatment duration of two histone deacetylase inhibitors-Trichostatin A (TSA) and Valproic acid (VPA) and two different embryo culture media (PZM-3 and HECM-10) on the in vitro development of iSCNT embryos. The results suggested that when PZM-3 was used as the embryo culture medium, the blastocyst rate of 10 nmol/L TSA treatment for 48 h was significantly higher than the control group (22.78% vs 9.86%, P< 0.05). However, neither in PZM-3 nor in HECM-10, 2-10 mmol/L VPA treatment did not increase the in vitro developmental potential of iSCNT embryos. It was concluded that TSA treatment could enhance the in vitro developmental potential of long-tailed macaque-pig iSCNT embryos.

Bioengineered BERA-Wnt5a siRNA Targeting Wnt5a/FZD2 Signaling Suppresses Advanced Prostate Cancer Tumor Growth and Enhances Enzalutamide Treatment.

The next-generation antiandrogen drugs such as enzalutamide and abiraterone extend survival times and improve quality of life in patients with advanced prostate cancer. However, resistance to both drugs occurs frequently through mechanisms that are incompletely understood. Wnt signaling, particularly through Wnt5a, plays vital roles in promoting prostate cancer progression and induction of resistance to enzalutamide and abiraterone. Development of novel strategies targeting Wnt5a to overcome resistance is an urgent need. In this study, we demonstrated that Wnt5a/FZD2-mediated noncanonical Wnt pathway is overexpressed in enzalutamide-resistant prostate cancer. In patient databases, both the levels of Wnt5a and FZD2 expression are upregulated upon the development of enzalutamide resistance and correlate with higher Gleason score, biochemical recurrence, and metastatic status, and with shortened disease-free survival duration. Blocking Wnt5a/FZD2 signal transduction not only diminished the activation of noncanonical Wnt signaling pathway, but also suppressed the constitutively activated androgen receptor (AR) and AR variants. Furthermore, we developed a novel bioengineered BERA-Wnt5a siRNA construct and demonstrated that inhibition of Wnt5a expression by the BERA-Wnt5a siRNA significantly suppressed tumor growth and enhanced enzalutamide treatment in vivo. These results indicate that Wnt5a/FZD2 signal pathway plays a critical role in promoting enzalutamide resistance, and targeting this pathway by BERA-Wnt5a siRNA can be developed as a potential therapy to treat advanced prostate cancer.

Olaparib-Induced Senescence Is Bypassed through G2-M Checkpoint Override in Olaparib-Resistant Prostate Cancer.

PARP inhibition represents the dawn of precision medicine for treating prostate cancer. Despite this advance, questions remain regarding the use of PARP inhibitors (PARPi) for the treatment of this disease, including (i) how specifically do PARPi-sensitive tumor cells respond to treatment, and (ii) how does PARPi resistance develop? To address these questions, we characterized response to olaparib in sensitive LNCaP and C4-2B cells and developed two olaparib-resistant derivative cell line models from each, termed LN-OlapR and 2B-OlapR, respectively. OlapR cells possess distinct morphology from parental cells and display robust resistance to olaparib and other clinically relevant PARPis, including rucaparib, niraparib, and talazoparib. In LNCaP and C4-2B cells, we found that olaparib induces massive DNA damage, leading to activation of the G2-M checkpoint, activation of p53, and cell-cycle arrest. Furthermore, our data suggest that G2-M checkpoint activation leads to both cell death and senescence associated with p21 activity. In contrast, both LN-OlapR and 2B-OlapR cells do not arrest at G2-M and display a markedly blunted response to olaparib treatment. Interestingly, both OlapR cell lines harbor increased DNA damage relative to parental cells, suggesting that OlapR cells accumulate and manage persistent DNA damage during acquisition of resistance, likely through augmenting DNA repair capacity. Further impairing DNA repair through CDK1 inhibition enhances DNA damage, induces cell death, and sensitizes OlapR cells to olaparib treatment. Our data together further our understanding of PARPi treatment and provide a cellular platform system for the study of response and resistance to PARP inhibition.

Wntless expression promotes lineage plasticity and is associated with neuroendocrine prostate cancer.

Resistance to androgen receptor (AR) targeted therapies remains as the main reason for most prostate cancer related deaths. Lineage plasticity resulting in altered, treatment insensitive prostate tumor cell phenotypes such neuroendocrine differentiated prostate cancer is a common manifestation within resistant tumors upon AR-targeted therapies. The mechanisms responsible for lineage plasticity in prostate cancer remain incompletely understood. Here we demonstrate that the enzalutamide resistant MDVR cell line possesses lineage plastic characteristics associated with overexpression of the Wnt transporter Wntless (WLS). Furthermore, we present evidence that overexpression of WLS is common in varying cell line models of lineage plastic prostate cancer, is higher in neuroendocrine patient samples, and positively correlates with the neuroendocrine marker SYP in clinical data. Targeting WLS in lineage plastic cellular models reduces viability and represses lineage plasticity associated gene expression. Our study provides insight into the importance of WLS to the development of lethal resistant prostate cancer and provides a potential target for the treatment of advanced disease.

Activation of neural lineage networks and ARHGEF2 in enzalutamide-resistant and neuroendocrine prostate cancer and association with patient outcomes.

Background: Treatment-emergent neuroendocrine prostate cancer (NEPC) after androgen receptor (AR) targeted therapies is an aggressive variant of prostate cancer with an unfavorable prognosis. The underlying mechanisms for early neuroendocrine differentiation are poorly defined and diagnostic and prognostic biomarkers are needed. Methods: We performed transcriptomic analysis on the enzalutamide-resistant prostate cancer cell line C4-2B MDVR and NEPC patient databases to identify neural lineage signature (NLS) genes. Correlation of NLS genes with clinicopathologic features was determined. Cell viability was determined in C4-2B MDVR and H660 cells after knocking down ARHGEF2 using siRNA. Organoid viability of patient-derived xenografts was measured after knocking down ARHGEF2. Results: We identify a 95-gene NLS representing the molecular landscape of neural precursor cell proliferation, embryonic stem cell pluripotency, and neural stem cell differentiation, which may indicate an early or intermediate stage of neuroendocrine differentiation. These NLS genes positively correlate with conventional neuroendocrine markers such as chromogranin and synaptophysin, and negatively correlate with AR and AR target genes in advanced prostate cancer. Differentially expressed NLS genes stratify small-cell NEPC from prostate adenocarcinoma, which are closely associated with clinicopathologic features such as Gleason Score and metastasis status. Higher ARGHEF2, LHX2, and EPHB2 levels among the 95 NLS genes correlate with a shortened survival time in NEPC patients. Furthermore, downregulation of ARHGEF2 gene expression suppresses cell viability and markers of neuroendocrine differentiation in enzalutamide-resistant and neuroendocrine cells. Conclusions: The 95 neural lineage gene signatures capture an early molecular shift toward neuroendocrine differentiation, which could stratify advanced prostate cancer patients to optimize clinical treatment and serve as a source of potential therapeutic targets in advanced prostate cancer.