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BACKGROUND: Despite nearly 100% 5-year survival for localised prostate cancer, the survival rate for metastatic prostate cancer significantly declines to 32%. Thus, it is crucial to identify molecular indicators that reflect the progression from localised disease to metastatic prostate cancer. METHODS: To search for molecular indicators associated with prostate cancer metastasis, we performed proteomic analysis of rapid autopsy tissue samples from metastatic prostate cancer (N = 8) and localised prostate cancer (N = 2). Then, we utilised multiple independent, publicly available prostate cancer patient datasets to select candidates that also correlate with worse prostate cancer clinical prognosis. RESULTS: We identified 154 proteins with increased expressions in metastases relative to localised prostate cancer through proteomic analysis. From the subset of these candidates that correlate with prostate cancer recurrence (N = 28) and shorter disease-free survival (N = 37), we identified a 5-gene signature panel with improved performance in predicting worse clinical prognosis relative to individual candidates. CONCLUSIONS: Our study presents a new 5-gene signature panel that is associated with worse clinical prognosis and is elevated in prostate cancer metastasis on both protein and mRNA levels. Our 5-gene signature panel represents a potential modality for the prediction of prostate cancer progression towards the onset of metastasis.
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Recapitulating spontaneous metastasis in preclinical models is crucial for understanding mechanisms underlying cancer progression and testing effective therapeutic interventions. We present a protocol for establishing and characterizing the spontaneous metastasis model in mice. We describe steps for generating primary tumors, tumor resection, monitoring metastatic dissemination, and evaluating metastatic burden using histological and imaging techniques. This protocol provides a valuable tool for studying metastasis in vivo and testing therapeutic strategies aimed at preventing or targeting metastatic diseases. For complete details on the use and execution of this protocol, please refer to Liu et al.1.
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Modelos Animales de Enfermedad , Metástasis de la Neoplasia , Animales , Ratones , Línea Celular Tumoral , FemeninoRESUMEN
Tibial shaft fractures are one of the most common orthopaedic injuries. Open tibial shaft fractures are relatively common because of the paucity of soft tissue surrounding the bone. Despite the prevalence of these injuries, the optimal fixation strategy is still a topic of debate. The purpose of this article was to review the current literature on open tibial shaft fracture fixation strategies including intramedullary nailing, external fixation, and plating.
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Purpose: Arthroscopic Bankart repair (ABR) may be more effective than nonoperative management for patients with anterior shoulder instability following first-time dislocation. The purpose of the study was to determine the most cost-effective treatment strategy by evaluating the incremental cost-effectiveness ratio (ICER) for ABR versus nonoperative treatment. Methods: This cost-effectiveness study utilized a Markov decision chain and Monte Carlo simulation. Probabilities, health utility values, and outcome data regarding ABR and nonoperative management of first-time shoulder instability derived from level I/II evidence. Costs were tabulated from Centers for Medicaid & Medicare Services. Probabilistic sensitivity analysis was performed using >100,000 repetitions of the Monte Carlo simulation. A willingness-to-pay (WTP) threshold was set at $50,000. Results: The expected cost for operative management higher than nonoperative management ($32,765 vs $29,343). However, ABR (5.48 quality-adjusted life years (QALYs)) was the more effective treatment strategy compared to nonoperative management (4.61 QALYs). The ICER for ABR was $3943. Probabilistic sensitivity analysis showed that ABR was the most cost-effective strategy in 100% of simulations. Discussion: ABR is more cost-effective than nonoperative management for first-time anterior shoulder dislocation. The threshold analysis demonstrated that when accounting for WTP, ABR was found to be the more cost-effective strategy.
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Neuroendocrine carcinomas, such as neuroendocrine prostate cancer and small-cell lung cancer, commonly have a poor prognosis and limited therapeutic options. We report that ubiquitin carboxy-terminal hydrolase L1 (UCHL1), a deubiquitinating enzyme, is elevated in tissues and plasma from patients with neuroendocrine carcinomas. Loss of UCHL1 decreases tumor growth and inhibits metastasis of these malignancies. UCHL1 maintains neuroendocrine differentiation and promotes cancer progression by regulating nucleoporin, POM121, and p53. UCHL1 binds, deubiquitinates, and stabilizes POM121 to regulate POM121-associated nuclear transport of E2F1 and c-MYC. Treatment with the UCHL1 inhibitor LDN-57444 slows tumor growth and metastasis across neuroendocrine carcinomas. The combination of UCHL1 inhibitors with cisplatin, the standard of care used for neuroendocrine carcinomas, significantly delays tumor growth in pre-clinical settings. Our study reveals mechanisms of UCHL1 function in regulating the progression of neuroendocrine carcinomas and identifies UCHL1 as a therapeutic target and potential molecular indicator for diagnosing and monitoring treatment responses in these malignancies.
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Carcinoma Neuroendocrino , Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Masculino , Humanos , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo , Carcinoma Neuroendocrino/tratamiento farmacológico , Carcinoma Neuroendocrino/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamiento farmacológico , Glicoproteínas de MembranaRESUMEN
Distinguishing indolent from clinically significant localized prostate cancer is a major clinical challenge and influences clinical decision-making between treatment and active surveillance. The development of novel predictive biomarkers will help with risk stratification, and clinical decision-making, leading to a decrease in over or under-treatment of patients with prostate cancer. Here, we report that Trop2 is a prognostic tissue biomarker for clinically significant prostate cancer by utilizing the Canary Prostate Cancer Tissue Microarray (CPCTA) cohort composed of over 1100 patients from a multi-institutional study. We demonstrate that elevated Trop2 expression is correlated with worse clinical features including Gleason score, age, and pre-operative PSA levels. More importantly, we demonstrate that elevated Trop2 expression at radical prostatectomy predicts worse overall survival in men undergoing radical prostatectomy. Additionally, we detect shed Trop2 in urine from men with clinically significant prostate cancer. Our study identifies Trop2 as a novel tissue prognostic biomarker and a candidate non-invasive marker for prostate cancer.
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Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/diagnóstico , Próstata/metabolismo , Pronóstico , Antígeno Prostático Específico , Prostatectomía , Biomarcadores de TumorRESUMEN
BACKGROUND: Neuroendocrine phenotype is commonly associated with therapy resistance and poor prognoses in small-cell neuroendocrine cancers (SCNCs), such as neuroendocrine prostate cancer (NEPC) and small-cell lung cancer (SCLC). Expression levels of current neuroendocrine markers exhibit high case-by-case variability, so multiple markers are used in combination to identify SCNCs. Here, we report that ACAA2 is elevated in SCNCs and is a potential molecular indicator for SCNCs. METHODS: ACAA2 expressions in tumour xenografts, tissue microarrays (TMAs), and patient tissues from prostate and lung cancers were analysed via immunohistochemistry. ACAA2 mRNA levels in lung and prostate cancer (PC) patients were assessed in published datasets. RESULTS: ACAA2 protein and mRNA levels were elevated in SCNCs relative to non-SCNCs. Medium/high ACAA2 intensity was observed in 78% of NEPC PDXs samples (N = 27) relative to 33% of adeno-CRPC (N = 86), 2% of localised PC (N = 50), and 0% of benign prostate specimens (N = 101). ACAA2 was also elevated in lung cancer patient tissues with neuroendocrine phenotype. 83% of lung carcinoid tissues (N = 12) and 90% of SCLC tissues (N = 10) exhibited medium/high intensity relative to 40% of lung adenocarcinoma (N = 15). CONCLUSION: ACAA2 expression is elevated in aggressive SCNCs such as NEPC and SCLC, suggesting it is a potential molecular indicator for SCNCs.
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Carcinoma Neuroendocrino , Carcinoma de Células Pequeñas , Neoplasias Pulmonares , Neoplasias de la Próstata , Carcinoma Pulmonar de Células Pequeñas , Humanos , Masculino , Carcinoma Neuroendocrino/patología , Carcinoma de Células Pequeñas/genética , Línea Celular Tumoral , Neoplasias Pulmonares/genética , Fenotipo , Neoplasias de la Próstata/patología , ARN Mensajero , Carcinoma Pulmonar de Células Pequeñas/genéticaRESUMEN
INTRODUCTION: Operating room air quality can be affected by several factors including temperature, humidity, and airborne particle burden. Our study examines the role of operating room (OR) size on air quality and airborne particle (ABP) count in primary total knee arthroplasty (TKA). MATERIALS AND METHODS: We analyzed all primary, elective TKAs performed within two ORs measuring 278 sq ft. (small) and 501 sq ft. (large) at a single academic institution in the United States from April 2019 to June 2020. Intraoperative measurements of temperature, humidity, and ABP count were recorded. p values were calculated using t test for continuous variables and chi-square for categorical values. RESULTS: 91 primary TKA cases were included in the study, with 21 (23.1%) in the small OR and 70 (76.9%) in the large OR. Between-groups comparisons revealed significant differences in relative humidity (small OR 38.5% ± 7.24% vs. large OR 44.4% ± 8.01%, p = 0.002). Significant percent decreases in ABP rates for particles measuring 2.5 µm (- 43.9%, p = 0.007) and 5.0 µm (- 69.0%, p = 0.0024) were found in the large OR. Total time spent in the OR was not significantly different between the two groups (small OR 153.09 ± 22.3 vs. large OR 173 ± 44.6, p = 0.05). CONCLUSIONS: Although total time spent in the room did not differ between the large and small OR, there were significant differences in humidity and ABP rates for particles measuring 2.5 µm and 5.0 µm, suggesting the filtration system encounters less particle burden in larger rooms. Larger studies are required to determine the impact this may have on OR sterility and infection rates.
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Contaminación del Aire , Artroplastia de Reemplazo de Rodilla , Humanos , Estados Unidos , Quirófanos , TemperaturaRESUMEN
BACKGROUND: Airborne biologic particles (ABPs) can be measured intraoperatively to evaluate operating room (OR) sterility. Our study examines the role of OR size on air quality and ABP count in primary total hip arthroplasty (THA). METHODS: We analyzed primary THA procedures done within 2 ORs measuring 278 ft2 and 501 ft2 at a single academic institution from April 2019 to June 2020. Temperature, humidity, and ABP count per minute were recorded with a particle counter intraoperatively and cross-referenced with surgical data from the electronic health records using procedure start and end times. Descriptive statistics were used to evaluate differences in variables. P-values were calculated using t-test and chi-squared test. RESULTS: A total of 116 primary THA cases were included: 18 (15.5%) in the "small" OR and 98 (84.5%) in the "large" OR. Between-group comparisons revealed significant differences in temperature (small OR: 20.3 ± 1.23 C versus large OR: 19.1 ± 0.85 C, P < .0001) and relative humidity (small OR: 41.1 ± 7.24 versus large OR: 46.9 ± 7.56, P < .001). Significant percent decreases in ABP rates for particles measuring 2.5 um (-125.0%, P = .0032), 5.0 um (-245.0%, P = .00078), and 10.0 um (-413.9%, P = .0021) were found in the large OR. Average time spent in the OR was significantly longer in the large OR (174 ± 33 minutes) compared to the small OR (151 ± 14 minutes) (P = .00083). CONCLUSION: Temperature and humidity differences and significantly lower ABP counts were found in the large compared to the small OR despite longer average time spent in the large OR, suggesting the filtration system encounters less particle burden in larger rooms. Further research is needed to determine the impact this may have on infection rates.
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Contaminación del Aire , Artroplastia de Reemplazo de Cadera , Humanos , Quirófanos , TemperaturaRESUMEN
The term "cistrome" refers to the genome-wide location of regulatory elements associated with transcription factor binding-sites. The cistrome of key regulatory factors in prostate cancer etiology are substantially reprogrammed and altered during prostatic transformation and disease progression. For instance, the cistrome of the androgen receptor (AR), a ligand-inducible transcription factor central in normal prostate epithelium biology, is directly impacted and substantially reprogrammed during malignant transformation. Accumulating evidence demonstrates that additional transcription factors that are frequently mutated, or aberrantly expressed in prostate cancer, such as the pioneer transcription factors Forkhead Box A1 (FOXA1), the homeobox protein HOXB13, and the GATA binding protein 2 (GATA2), and the ETS-related gene (ERG), and the MYC proto-oncogene, contribute to the reprogramming of the AR cistrome. In addition, recent findings have highlighted key roles for the SWI/SNF complex and the chromatin-modifying helicase CHD1 in remodeling the epigenome and altering the AR cistrome during disease progression. In this review, we will cover the role of cistromic reprogramming in prostate cancer initiation and progression. Specifically, we will discuss the impact of key prostate cancer regulators, as well as the role of epigenetic and chromatin regulators in relation to the AR cistrome and the transformation of normal prostate epithelium. Given the importance of chromatin-transcription factor dynamics in normal cellular differentiation and cancer, an in-depth assessment of the factors involved in producing these altered cistromes is of great relevance and provides insight into new therapeutic strategies for prostate cancer.
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Alzheimer's disease (AD) is a major cause of age-related dementia and is characterized by progressive brain damage that gradually destroys memory and the ability to learn, which ultimately leads to the decline of a patient's ability to perform daily activities. Although some of the pharmacological treatments of AD are available for symptomatic relief, they are not able to limit the progression of AD and have several side effects. Mesenchymal stem/stromal cells (MSCs) could be a potential therapeutic option for treating AD due to their immunomodulatory, anti-inflammatory, regenerative, antioxidant, anti-apoptotic, and neuroprotective effects. MSCs not only secret neuroprotective and anti-inflammatory factors to promote the survival of neurons, but they also transfer functional mitochondria and miRNAs to boost their bioenergetic profile as well as improve microglial clearance of accumulated protein aggregates. This review focuses on different clinical and preclinical studies using MSC as a therapy for treating AD, their outcomes, limitations and the strategies to potentiate their clinical translation.
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Somatostatin receptors (SSTRs) play versatile roles in inhibiting the secretion of multiple hormones such as growth hormone and thyroid-stimulating hormone, and thus are considered as targets for treating multiple tumors. Despite great progress made in therapeutic development against this diverse receptor family, drugs that target SSTRs still show limited efficacy with preferential binding affinity and conspicuous side-effects. Here, we report five structures of SSTR2 and SSTR4 in different states, including two crystal structures of SSTR2 in complex with a selective peptide antagonist and a non-peptide agonist, respectively, a cryo-electron microscopy (cryo-EM) structure of Gi1-bound SSTR2 in the presence of the endogenous ligand SST-14, as well as two cryo-EM structures of Gi1-bound SSTR4 in complex with SST-14 and a small-molecule agonist J-2156, respectively. By comparison of the SSTR structures in different states, molecular mechanisms of agonism and antagonism were illustrated. Together with computational and functional analyses, the key determinants responsible for ligand recognition and selectivity of different SSTR subtypes and multiform binding modes of peptide and non-peptide ligands were identified. Insights gained in this study will help uncover ligand selectivity of various SSTRs and accelerate the development of new molecules with better efficacy by targeting SSTRs.
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Neoplasias , Receptores de Somatostatina , Microscopía por Crioelectrón , Humanos , Ligandos , Neoplasias/metabolismo , Receptores de Somatostatina/agonistas , Receptores de Somatostatina/metabolismo , Somatostatina/metabolismo , Somatostatina/farmacología , Somatostatina/uso terapéuticoRESUMEN
Distant metastasis is the main cause of death in prostate cancer patients. Notch signaling plays an important role in driving prostate cancer aggressiveness and metastasis. In this chapter, we describe a protocol to measure prostate cancer metastatic colonization, incidences of metastasis, accurately quantify the burden of metastasis, and test the role of NOTCH1 receptor on prostate cancer metastatic colonization and homing to distant sites. The metastasis model presented here is established by intracardiac injection of control human prostate cancer cells and NOTCH1 downregulated cells. The cells are engineered to express both red fluorescent protein (RFP) and luciferase. In this model, whole body bioluminescence imaging, high-resolution, and quantitative fluorescence imaging are utilized for quantitative assessment of metastatic colonization and metastasis burden. Further, histopathology analyses of diverse metastatic organs are performed. This model is a powerful and versatile tool to investigate the mechanisms underlying the function of NOTCH receptors in metastatic colonization in prostate cancer.
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Neoplasias de la Próstata , Línea Celular Tumoral , Humanos , Masculino , Metástasis de la Neoplasia , Neoplasias de la Próstata/patología , Receptor Notch1/genética , Receptor Notch1/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Transducción de SeñalRESUMEN
Among men, prostate cancer is the second leading cause of cancer-associated mortality, with advanced disease remaining a major clinical challenge. We describe a small molecule, SU086, as a therapeutic strategy for advanced prostate cancer. We demonstrate that SU086 inhibits the growth of prostate cancer cells in vitro, cell-line and patient-derived xenografts in vivo, and ex vivo prostate cancer patient specimens. Furthermore, SU086 in combination with standard of care second-generation anti-androgen therapies displays increased impairment of prostate cancer cell and tumor growth in vitro and in vivo. Cellular thermal shift assay reveals that SU086 binds to heat shock protein 90 (HSP90) and leads to a decrease in HSP90 levels. Proteomic profiling demonstrates that SU086 binds to and decreases HSP90. Metabolomic profiling reveals that SU086 leads to perturbation of glycolysis. Our study identifies SU086 as a treatment for advanced prostate cancer as a single agent or when combined with second-generation anti-androgens.
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Neoplasias de la Próstata , Proteómica , Proliferación Celular , Glucólisis , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Masculino , Neoplasias de la Próstata/tratamiento farmacológicoRESUMEN
Breast cancer remains the second most lethal cancer among women in the United States and triple-negative breast cancer is the most aggressive subtype with limited treatment options. Trop2, a cell membrane glycoprotein, is overexpressed in almost all epithelial cancers. In this study, we demonstrate that Trop2 is overexpressed in triple-negative breast cancer (TNBC), and downregulation of Trop2 delays TNBC cell and tumor growth supporting the oncogenic role of Trop2 in breast cancer. Through proteomic profiling, we discovered a metabolic signature comprised of TALDO1, GPI, LDHA, SHMT2, and ADK proteins that were downregulated in Trop2-depleted breast cancer tumors. The identified oncogene-mediated metabolic gene signature is significantly upregulated in TNBC patients across multiple RNA-expression clinical datasets. Our study further reveals that the metabolic gene signature reliably predicts poor survival of breast cancer patients with early stages of the disease. Taken together, our study identified a new five-gene metabolic signature as an accurate predictor of breast cancer outcome.
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Neuroendocrine prostate cancer (NEPC) is a lethal subtype of prostate cancer that rarely develops de novo in primary tumors and is commonly acquired during the development of treatment resistance. NEPC is characterized by gain of neuroendocrine markers and loss of androgen receptor (AR), making it resistant to current therapeutic strategies targeting the AR signaling axis. Here, we report that MCM2, MCM3, MCM4, and MCM6 (MCM2/3/4/6) are elevated in human NEPC and high levels of MCM2/3/4/6 are associated with liver metastasis and poor survival in prostate cancer patients. MCM2/3/4/6 are four out of six proteins that form a core DNA helicase (MCM2-7) responsible for unwinding DNA forks during DNA replication. Inhibition of MCM2-7 by treatment with ciprofloxacin inhibits NEPC cell proliferation and migration in vitro, significantly delays NEPC tumor xenograft growth, and partially reverses the neuroendocrine phenotype in vivo. Our study reveals the clinical relevance of MCM2/3/4/6 proteins in NEPC and suggests that inhibition of MCM2-7 may represent a new therapeutic strategy for NEPC.
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Carcinoma Neuroendocrino/metabolismo , Componente 2 del Complejo de Mantenimiento de Minicromosoma/metabolismo , Componente 7 del Complejo de Mantenimiento de Minicromosoma/metabolismo , Proteínas de Mantenimiento de Minicromosoma/metabolismo , Tumores Neuroendocrinos/metabolismo , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , Animales , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/fisiología , Humanos , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Células PC-3 , Receptores Androgénicos/metabolismo , Transducción de Señal/fisiología , Regulación hacia Arriba/fisiología , Ensayos Antitumor por Modelo de Xenoinjerto/métodosRESUMEN
Prostate cancer remains the most common non-cutaneous malignancy among men in the United States. To discover potential serum-based biomarkers for high-risk prostate cancer, we performed a high-multiplex immunoassay utilizing patient-matched pre-operative and post-operative serum samples from ten men with high-grade and high-volume prostate cancer. Our study identified six (CASP8, MSLN, FGFBP1, ICOSLG, TIE2 and S100A4) out of 174 proteins that were significantly decreased after radical prostatectomy. High levels of CASP8 were detected in pre-operative serum samples when compared to post-operative serum samples and serum samples from patients with benign prostate hyperplasia (BPH). By immunohistochemistry, CASP8 protein was expressed at higher levels in prostate cancer tissues compared to non-cancerous and BPH tissues. Likewise, CASP8 mRNA expression was significantly upregulated in prostate cancer when compared to benign prostate tissues in four independent clinical datasets. In addition, mRNA levels of CASP8 were higher in patients with recurrent prostate cancer when compared to patients with non-recurrent prostate cancer and high expression of CASP8 was associated with worse disease-free survival and overall survival in renal cancer. Together, our results suggest that CASP8 may potentially serve as a biomarker for high-risk prostate cancer and possibly renal cancer.
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Caspasa 8/genética , Neoplasias de la Próstata/genética , Anciano , Biomarcadores de Tumor/sangre , Caspasa 8/metabolismo , Supervivencia sin Enfermedad , Humanos , Inmunoensayo/métodos , Inmunohistoquímica/métodos , Pruebas Inmunológicas/métodos , Masculino , Mesotelina , Persona de Mediana Edad , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/metabolismo , Próstata/patología , Antígeno Prostático Específico/sangre , Prostatectomía , Hiperplasia Prostática/metabolismo , Neoplasias de la Próstata/metabolismo , Factores de RiesgoRESUMEN
Prostate cancer remains the second leading cause of cancer-associated deaths amongst American men. Trop2, a cell surface glycoprotein, correlates with poor clinical outcome and is highly expressed in metastatic, treatment-resistant prostate cancer. High levels of Trop2 are prognostic for biochemical recurrence. Trop2 regulates tumor growth and metastatic ability of prostate cancer. Moreover, overexpression of Trop2 drives the transdifferentiation to neuroendocrine phenotype in prostate cancer. In addition, Trop2 is overexpressed across epithelial cancers and has emerged as a promising therapeutic target in various solid epithelial cancers. The FDA (Food and Drug Administration) recently approved the use of a Trop2-targeting ADC (antibody-drug conjugate), Sacituzumab Govitecan (IMMU-132), for metastatic, triple-negative breast cancer with at least two prior therapies. Here, we review the role of Trop2 in prostate tumorigenesis and its potential as a promising biomarker and therapeutic target for prostate cancer.
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The maintenance of telomeres, which are specialized stretches of DNA found at the ends of linear chromosomes, is a crucial step for the immortalization of cancer cells. Approximately 10-15 % of cancer cells use a homologous recombination-based mechanism known as the Alternative Lengthening of Telomeres (ALT) pathway to maintain their telomeres. Telomeres in general pose a challenge to DNA replication owing to their repetitive nature and potential for forming secondary structures. Telomeres in ALT+ cells especially are subject to elevated levels of replication stress compared to telomeres that are maintained by the enzyme telomerase, in part due to the incorporation of telomeric variant repeats at ALT+ telomeres, their on average longer lengths, and their modified chromatin states. Many DNA metabolic strategies exist to counter replication stress and to protect stalled replication forks. The role of proliferating cell nuclear antigen (PCNA) as a platform for recruiting protein partners that participate in several of these DNA replication and repair pathways has been well-documented. We propose that many of these pathways may be active at ALT+ telomeres, either to facilitate DNA replication, to manage replication stress, or during telomere extension. Here, we summarize recent evidence detailing the role of PCNA in pathways including DNA secondary structure resolution, DNA damage bypass, replication fork restart, and DNA damage synthesis. We propose that an examination of PCNA and its post-translational modifications (PTMs) may offer a unique lens by which we might gain insight into the DNA metabolic landscape that is distinctively present at ALT+ telomeres.