Survival In Prostate Cancer Patients Research Articles

Biochemical Response of

BackgroundIn a subset of patients with oligorecurrent prostate cancer (PCa), salvage surgery with prostate-specific membrane antigen (PSMA) radioguided surgery (PSMA-RGS) seems to be of value. ObjectiveTo evaluate whether a lower level of postoperative prostate-specific antigen (PSA; <0.1 ng/ml) is predictive of therapy-free survival (TFS) following salvage PSMA-RGS. Design, setting, and participantsThis cohort study evaluated patients with biochemical recurrence after radical prostatectomy and oligorecurrent PCa on PSMA positron emission tomography treated with PSMA-RGS in three tertiary care centers (2014–2022). InterventionPSMA-RGS. Outcome measurements and statistical analysisPostsalvage surgery PSA response was categorized as <0.1, 0.1–<0.2, or >0.2 ng/ml. Kaplan-Meier and multivariable Cox regression models evaluated TFS according to PSA response. Results and limitationsAmong 553 patients assessed, 522 (94%) had metastatic soft tissue lesions removed during PSMA-RGS. At 2–16 wk after PSMA-RGS, 192, 62, and 190 patients achieved PSA levels of <0.1, 0.1–<0.2, and >0.2 ng/ml, respectively. At 2 yr of follow-up, TFS rate was 81.1% versus 56.1% versus 43.1% (p < 0.001) for patients with PSA <0.1 versus 0.1–<0.2 versus >0.2 ng/ml. In multivariable analyses, PSA levels of 0.1–0.2 ng/ml (hazard ratio [HR]: 1.9, confidence interval [CI]: 1.1–3.1) and ≥0.2 ng/ml (HR: 3.2, CI: 2.2–4.6, p < 0.001) independently predicted the need for additional therapy after PSMA-RGS. The main limitation is the lack of a control group. ConclusionsFor patients after salvage PSMA-RGS, a lower biochemical response (PSA <0.1 ng/ml) seems to predict longer TFS. This insight may help in counseling patients postoperatively as well as guiding the timely selection of additional therapy. Patient summaryWe studied what happened to prostate cancer patients in three European centers who had salvage surgery using a special method called prostate-specific membrane antigen–targeted radioguidance. We found that patients who had low prostate-specific antigen levels soon after surgery were less likely to need further treatment for a longer time.

Identification and validation of a novel anoikis-related prognostic model for prostate cancer.

Anoikis resistance is a hallmark characteristic of oncogenic transformation, which is crucial for tumor progression and metastasis. The aim of this study was to identify and validate a novel anoikis-related prognostic model for prostate cancer (PCa). We collected a gene expression profile, single nucleotide polymorphism mutation and copy number variation (CNV) data of 495 PCa patients from the TCGA database and 140 PCa samples from the MSKCC dataset. We extracted 434 anoikis-related genes and unsupervised consensus cluster analysis was used to identify molecular subtypes. The immune infiltration, molecular function, and genome alteration of subtypes were evaluated. A risk signature was developed using Cox regression analysis and validated with the MSKCC dataset. We also identify potential drugs for high-risk group patients. Two subtypes were identified. C1 exhibited a higher level of CNV amplification, immune score, stromal score, aneuploidy score, homologous recombination deficiency, intratumor heterogeneity, single-nucleotide variant neoantigens, and tumor mutational burden compared to C2. C2 showed a better survival outcome and had a high level of gamma delta T cell and activated B cell infiltration. The risk signature consisting of four genes (HELLS, ZWINT, ABCC5, and TPSB2) was developed (area under the curve = 0.780) and was found to be an independent prognostic factor for overall survival in PCa patients. Four CTRP-derived and four PRISM-derived compounds were identified for high-risk patients. The anoikis-related prognostic model developed in this study could be a useful tool for clinical decision-making. This study may provide a new perspective for the treatment of anoikis-related PCa.

Abstract 773: Overexpression of phosphoserine phosphatase (PSPH) in prostate cancer and in tumor microenvironment promotes tumor cell proliferation

Abstract Reprogrammed cellular metabolism is one of the key features of cancer and tumor microenvironment. L-3-phosphoserine phosphatase (PSPH) is one of the five rate-limiting enzymes in the biosynthesis of serine from glucose that supports cell proliferation. Here, we aim to study the role of PSPH in prostate cancer (PCa) and its tumor microenvironment. We find that PSPH not only is overexpressed in prostate cancer cell lines compared to normal prostate epithelial cells (PrEC) and benign prostate epithelial cells (BPH-1), but also exhibits a higher level in patient-derived carcinoma-associated fibroblasts (CAFs) compared to the matched benign associated fibroblasts (BAFs), which are derived from fresh radical prostatectomy specimens of African American (AA) and European American (EA) men. Notably, MDAPCa2b cells derived from an AA prostate cancer patient and AA CAFs have even higher expression of PSPH protein. The mRNA levels of PSPH are also significantly elevated in prostate cancer tissues in AA men compared to EA men and predict poor survival in PCa patients. Knock-down of PSPH expression significantly inhibits the proliferation and colony formation of prostate cancer cells. Growth of xenograft tumors derived from PSPH knockdown MDAPCa2b cells has also been suppressed markedly. Gene expression profiling revealed that suppression of PSPH expression by shRNAs in LNCaP and MDAPCa2b cells is associated with the regulation of gene expression related to metabolism, immunity, extracellular matrix remodeling, and Ion channels. Similarly, analysis of publicly available PCa RNA seq databases also demonstrates that PSPH amplification or over-expression is associated with alterations of gene expression related to metabolism and immunity. Our results suggest that PSPH is upregulated in prostate cancer cells and their surrounding fibroblasts to support tumor growth via reprogramming metabolic pathways and transcriptomes. Citation Format: Liankun Song, Noriko Yokoyama, Jun Xie, Yunjie Hu, Zhenyu (Arthur) Jia, Beverly Wang, Dan Mercola, Edward Uchio, Thomas Ahlering, Michael Lilly, Xiaolin Zi. Overexpression of phosphoserine phosphatase (PSPH) in prostate cancer and in tumor microenvironment promotes tumor cell proliferation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 773.

Abstract 3577: The role of PLXND1 in lineage plasticity and progression to neuroendocrine prostate cancer

Abstract Background: Neuroendocrine prostate cancer (NEPC) is a lethal subtype of prostate cancer and is commonly associated with therapy resistance and poor prognosis. Treatment-induced NEPC (t-NEPC) predominantly develops by lineage plasticity from adenocarcinoma in response to androgen receptor signaling inhibitors, such as enzalutamide. However, the mechanisms underlying the lineage plasticity and progression to NEPC are unclear. PLXND1 (PlexinD1) is a cellular receptor of the semaphorin family and has important functions in modulating the cytoskeleton and cell adhesion. However, the role of PLXND1 in lineage plasticity to NEPC development and progression is not well established. Methods: We performed transcriptomic analysis on NEPC patients’ cohorts and the enzalutamide-resistant prostate cancer cell lines. Correlation of PLXND1 with neuroendocrine feature genes and AR-targeting genes was determined. Kaplan-Meier method and the Cox proportional hazards model was used to estimate the correlation between PLXND1 expression level and patients’ survival. Immunohistochemistry was used to analyze PLXND1 expression in prostate adenocarcinoma and NEPC. Cell viability was determined in C4-2B MDVR, CWR22Rv1, and H660 cells after knocking down PLXND1 using siRNA or knocking out PLXND1 using CRISPR/CAS9. Organoids viability of patient-derived xenografts was measured after knocking down or knocking out PLXND1. Results: Our analysis on different patient cohorts suggests that PLXND1 is highly expressed in NEPC patients, and the expression of PLXND1 is positively correlated with neuroendocrine feature genes (CHGA, ENO2, SYP, and NCAM1). Kaplan-Meier survival analysis shows that high expression of PLXND1 is significantly associated with the poor prognosis of prostate cancer patients. PLXND1 is overexpressed and negatively regulated by androgen receptor signaling in enzalutamide-resistant cells and prostate cancer patients’ cohorts. Furthermore, downregulation of PLXND1 expression suppressed proliferation of the NEPC cells and viability of the PDX tumor organoids. Conclusions: PLXND1 expression is elevated in NEPC and correlated with the poor survival of prostate cancer patients, suggesting it is a potential molecular indicator and therapy target for NEPC. Citation Format: Bo Chen, Pengfei Xu, Joy C. Yang, Shu Ning, Leyi Wang, Christopher Nip, Allen C. Gao, Chengfei Liu. The role of PLXND1 in lineage plasticity and progression to neuroendocrine prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3577.

Abstract 104: Profiling peripheral blood to predict response to targeted androgen receptor axis therapy in mice

Abstract Background: Targeting the androgen receptor (AR) signaling axis (ARAT) continues to be the mainstay treatment for advanced-stage prostate cancer. Using second-generation antiandrogens like abiraterone acetate (Abi) and apalutamide (Apa) has contributed to the survival of prostate cancer patients. However, resistance to these therapies remains a problem and most of these patients progress to castration-resistant prostate cancer (CRPC). Myeloid-derived suppressor cells (MDSCs) have been shown to drive CRPC. We previously showed that unfavorable responses to androgen deprivation therapy (ADT) or ADT plus Apa were associated with polymorphonuclear MDSCs (PMN-MDSCs) cells enriched in prostate tumors from conditional Pten/Trp53-double knockout (DKO) mice. Here, we explore the association between pre-treatment immune cell subsets blood and antitumor to ARAT therapy DKO mice. Methods: Twenty-eight-week-old DKO mice were surgically castrated and after four weeks were randomized to treatments with vehicle, Apa or Abi for an additional four weeks (n=20). Individual treatment responses were assessed and classified according to tumor burden as follows: high tumor burden (HTB), ≥20% of median; moderate tumor burden (MTB), -20% to 20% of median; or low tumor burden (LTB), ≤-20% of median. Peripheral blood was collected both before and after treatment and analyzed by multi-color flow cytometry panels for lymphoid and myeloid subsets. Blood samples from healthy wildtype and untreated DKO mice with castration-naïve prostate tumors were collected as reference samples. Subsets of PMN-MDSCs and monocytic-MDCSs (m-MDSCs) were represented as % of total abundance and 5 of parental population. revealed a signature that was correlated with treatment responses. Profiles were constructed and the data was used to train supervised learning models to predict treatment responses. Shapely additive explanations (ShAP) were used to determine feature importance. The model was tested and validated on an independent cohort of 20 DKO mice treated with ADT and ADT plus Abi. Results: Moderate prediction from baseline blood could be identified for tumor burden following ARAT using a Naïve Bayes classifier. Model evaluation, using an independent cohort, yielded favorable performance with area under the curve (AUC) mean, 0.707; HTB, 0.627; MTB, 0.750; and LTB, 0.745. The most important features for prediction were identified. Conclusion: Our study revealed that MDSC subsets present in blood were associated with treatment responses to ARAT. Citation Format: Marco A. De Velasco, Yurie Kura, Kazuko Sakai, Yoshitaka Saito, Takafumi Minami, Kazuhiro Yoshimura, Kazutoshi Fujita, Kazuto Nishio, Hirotsugu Uemura. Profiling peripheral blood to predict response to targeted androgen receptor axis therapy in mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 104.

Abstract 6276: In vitro neuroendocrine differentiation of BPH-1 cells under beta-adrenergic stimulation

Abstract Recent studies have shown that adrenergic fibers from the sympathetic nervous system (SNS), acting through stromal β2-adrenergic receptors, play an important role in the initial phases of cancer development by promoting tumor cell survival. Recent epidemiological data suggest that β-blocker intake is associated with improved survival of prostate cancer patients. Hypertension and high blood pressure have been suggested to increase prostate cancer development suggesting that the use of β-blockers in these patients could also reduce prostate cancer risk. β-adrenoceptors signal through the cAMP/PKA pathway that is known to promote neuroendocrine differentiation (NED) in LNCaP prostate cancer cell line. While neuroendocrine (NE) cells expressing synaptophysin (SYN) represent a minor cell population in the epithelial compartment of normal prostate glands, the population of NE-like cells, exhibiting NE phenotypes and expressing NE markers, is increased in, and correlates with, cancer progression, androgen-independent state and poor prognosis. Expression of the routine tissue biomarker of prostate cancer AMACR in NE-like cells discriminates them from NE cells. Our aim was to investigate whether NED could also be associated with benign prostatic hyperplasia (BPH) as recent studies showed that an increase in neuroendocrine cell density occurred before development of BPH in hypertensive rats. Our results showed that a 10-day treatment with 100µM IBMX (blocking cAMP degradation) and 10µM forskolin (FSK, adenylate cyclase activator) to trigger sustained activation of the cAMP/PKA pathway led to an increase in SYN and AMACR expression in BPH-1 cells (qPCR and WB). Similar results were observed by combining the effect of the β-adrenoceptor agonist isoproterenol (1µM) and FSK. The same treatments reduced BPH-1 cell proliferation rates by 40% and 60%, respectively, as expected for NED. Effects on AMACR and SYN expression and cell proliferation were fully reversed by the β-blocker carvedilol (5µM). This data suggests that β-adrenoceptors could be linked to the development of NE-like cells in BPH, a non-lethal disease affecting the transition zone (TZ). As 20% of the prostate cancer occur in this TZ, this observation may need further investigation. Citation Format: Natascha Pigat, Laura N. Garrido, Coline Lefevre, Manon Baures, Vincent Goffin, Anne-Sophie Armand, Thierry Capiod. In vitro neuroendocrine differentiation of BPH-1 cells under beta-adrenergic stimulation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6276.

Abstract 5648: Decoding the non-canonical functions of HO-1 in prostate cancer: A nuclear perspective and its association with a neuroendocrine signature

Abstract Previous studies have demonstrated the non-canonical anti-tumor effect of heme-oxygenase 1 (HO-1) in prostate cancer (PCa). Although HO-1 is crucial for free heme degradation, its nuclear expression unveils non-canonical functions beyond its enzymatic function. Understanding the specifics of its non-canonical role remains a critical unmet need. In this study, we identified nuclear interactors of HO-1 and assessed their association with PCa.PCa cells were treated with hemin (80 µM, 24 h), a specific pharmacological inducer of HO-1. Nuclear HO-1 immunoprecipitation and LC-ESI MS/MS analysis identified 11 differential nuclear associated-HO-1 proteins between control and hemin-treated PCa cells (ILF3, ILF2, BCLAF1, SAFB, DDX17, SLC25A5, CASP14, PRDX1, BRIX1, CCDC175, and GPATCH1). Next, we performed an Ingenuity Pathway Analysis (QIAGEN) showing that ILF3 appears as a master regulator of this signature. To assess the clinical relevance of these factors in PCa, we analyzed overall survival (OS), progression-free survival (PFS), relapse free survival (RFS) in multiple PCa datasets (GSE34312, GSE35988, GSE3933, GSE46602, GSE6956, GSE70768, TCGA-PRAD, GSE70770, GSE16560, GSE24136; n=1064). We performed univariable and multivariable analyses for these factors and identified the ones that significantly and independently affected the OS, RFS, PFS. Next, a risk score model was built based on the expression of 9 genes (∑ni=1(Coefi×Expri)) for the GSE70770 dataset using these factors identifying a subpopulation of PCa patients with high-risk of RFS (HR: 7.39 High vs Low score, p&amp;lt;0.0001); ascertaining the critical role of this signature in PCa. To elucidate the association of these factors with the aggressive phenotype of PCa, we analyzed RNA-seq expression data from the MDA-PCa-PDXs series (PCa Patient Derived Xenografts Program; MD Anderson Cancer Center), capturing PCa heterogeneity. Unsupervised clustering analysis revealed that samples with high expression of HO-1 nuclear interactors corresponded to neuroendocrine tumors, negative for androgen receptor staining. Principal Component Analysis identified ILF3 as the most relevant HO-1 interactor driving PDXs’ samples variance, correlating with a significant decrease in relapse-free survival of PCa patients. Further, we used ChIP-Atlas to assess the epigenomic landscapes for these nuclear HO-1 interactors. Results indicated that 40% of HO-1 nuclear interactors were potential transcription regulators. Strikingly, KEGG pathways analyses revealed that their regulomes were significantly associated with neurodegenerative disorders, highlighting their relevance in neural processes. In conclusion, our findings suggest that HO-1 and its nuclear interactors may play a pivotal role in neuroendocrine PCa, shedding light on potential therapeutic targets for this aggressive form of the disease. Citation Format: Seniuk A. Rocio, Agustina Sabater, Pablo Sanchis, Juan Bizzotto, Gastón Pascual, Estefania Labanca, Nicolas Anselmino, Nora Navone, Elba Vazquez, Pia Valacco, Javier Cotignola, Ayelén Toro, Geraldine Gueron. Decoding the non-canonical functions of HO-1 in prostate cancer: A nuclear perspective and its association with a neuroendocrine signature [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5648.

A study on the impact of marital status on the survival status of prostate cancer patients based on propensity score matching

Marital status is an independent prognostic factor for survival in many types of cancers, but its prognostic impact on patients with prostate cancer (PCa) has not been established. The aim of this study was to explore the independent prognostic factors of PCa and to investigate the effect of marital status on survival outcomes in patients with different stratified by PCa. Using the surveillance, epidemiology, and end results (SEER) database, we collected data on 584,655 PCa patients diagnosed between 1975 and 2019. Marital status was classified as married, divorced, widowed, and single. We used the Kaplan–Meier analysis and single multivariate Cox proportional hazards regression analysis to determine the effect of marital status on overall survival (OS) and cancer-specific survival (CSS). In addition, we performed subgroup analyses for different ages, Gleason score and PSA values, and performed a 1:1 propensity score matching (PSM) to reduce the impact of confounding factors to obtain more accurate matching results. According to our findings, marital status was an independent prognostic factor for the survival of PCa patients and a better prognosis of married patients. Moreover, we also found that factors such as age, TNM stage, Gleason score, and PSA concentration were also considered as important predictors for the prognosis of PCa. The above findings can facilitate early detection and treatment of high-risk PCa patients, prolong their life and reduce family burden.

CRISPR/Cas9 screenings unearth protein arginine methyltransferase 7 as a novel essential gene in prostate cancer metastasis

Due to the limited effectiveness of current treatments, the survival rate of patients with metastatic castration-resistant prostate cancer (mCRPC) is significantly reduced. Consequently, it is imperative to identify novel therapeutic targets for managing these patients. Since the invasive ability of cells is crucial for establishing and maintaining metastasis, the aim of this study was to identify the essential regulators of invasive abilities of mCRPC cells by conducting two independent high-throughput CRISPR/Cas9 screenings. Furthermore, some of the top hits were validated using siRNA technology, with protein arginine methyltransferase 7 (PRMT7) emerging as the most promising candidate. We demonstrated that its inhibition or depletion via genetic or pharmacological approaches significantly reduces invasive, migratory and proliferative abilities of mCRPC cells in vitro. Moreover, we confirmed that PRMT7 ablation reduces cell dissemination in chicken chorioallantoic membrane and mouse xenograft assays. Molecularly, PRMT7 reprograms the expression of several adhesion molecules by methylating various transcription factors, such as FoxK1, resulting in the loss of adhesion from the primary tumor and increased motility of mCRPC cells. Furthermore, PRMT7 higher expression correlates with tumor aggressivity and poor overall survival in prostate cancer patients. Thus, this study demonstrates that PRMT7 is a potential therapeutic target and potential biomarker for mPCa.

Ubiquitin B, Ubiquitin C, and β-Catenin as Promising Diagnostic and Prognostic Tools in Prostate Cancer.

Prostate cancer (PC) is a major global public health concern, imposing a significant burden on men and ranking as the second most prevalent malignancy. This study delves into the intricate world of ubiquitination processes and expression regulation, with a specific focus on understanding the roles of ubiquitin B (UBB), ubiquitin C (UBC), and β-Catenin in PC development. We thoroughly analyze the expression profiles of UBB, UBC, and β-Catenin, investigating their interactions and associations with clinical and histopathological data. These findings offer valuable insights into their potential as robust prognostic markers and their significance for patient survival. Our research uncovers the upregulation of UBB and UBC expression in PC tissues, and an even more pronounced expression in lymph node metastases, highlighting their pivotal roles in PC progression. Moreover, we identify a compelling correlation between high UBB and UBC levels and diminished overall survival in PC patients, emphasizing their clinical relevance. Additionally, we observe a significant reduction in membranous β-Catenin expression in PC tissues. Importantly, abnormal β-Catenin expression is strongly associated with shorter survival in PC patients and serves as a significant, independent prognostic factor for patient outcomes. Kaplan-Meier survival analysis indicates that patients with tumors characterized by simultaneous UBB and aberrant β-Catenin expression exhibit the poorest overall survival. These collective insights underline the clinical importance of evaluating UBB, UBC, and β-Catenin as combined prognostic markers in PC.

Pretreatment Interstitial Lung Abnormalities Detected on Abdominal Computed Tomography Scans in Prostate Cancer Patients.

Prostate cancer and interstitial lung abnormality (ILA) share similar risk factor, which is men and older age. The purpose of this study was to investigate the prevalence of pretreatment ILA among prostate cancer patients who underwent abdominal computed tomography (CT) within 1 year at their first visit to the urology department. In addition, we aimed to assess the association between pretreatment ILA and long-term survival in prostate cancer patients. This study was conducted in patients who had a first visit for prostate cancer at urology department between 2005 and 2016 and underwent an abdominal CT within 1 year. A thoracic radiologist evaluated the presence of ILA through inspecting the lung base scanned on an abdominal CT. The association between pretreatment ILA and survival was assessed using Kaplan-Meier analysis with log-rank test. Specific survival rates at 12, 36, and 60 months according to the presence of ILA were evaluated using z -test. Cox regression analysis was used to assess the risk factors of mortality. A total of 173 patients were included (mean age, 70.23 ± 7.98 years). Pretreatment ILA was observed in 10.4% of patients. Patients with ILA were more likely to be older and current smokers. Pretreatment ILA was associated with poor survival ( P < 0.001). Age ≥70 years (hazards ratio [HR], 1.98; 95% confidence interval [CI], 1.24-3.16; P = 0.004), metastatic stage (HR, 2.26; 95% CI, 1.36-3.74; P = 0.002), and ILA (HR, 1.96; 95% CI, 1.06-3.60; P = 0.031) were the independent risk factors of mortality. An ILA (HR, 3.94; 95% CI, 1.78-8.72; P = 0.001) was the only independent risk factor of mortality in localized stage prostate cancer patients. This study provides important insights into the unexplored effect of pretreatment ILA in prostate cancer patients. Pretreatment ILAs were observed considerably in the lung bases scanned on the abdominal CT scans among prostate cancer patients. Furthermore, pretreatment ILAs were the risk factor of mortality. Therefore, lung bases should be routinely inspected in the abdominal CT scans of prostate cancer patients. This result may help clinicians in establishing personalized management strategy of prostate cancer patients.

Abstract A025: FANCI regulates Fanconi anemia pathway and counteracts the effects of DNA damaging chemotherapy in prostate cancer

Abstract Prostate cancer is one of the leading causes of death among men worldwide and thus research on the genetic factors enabling the formation of treatment resistant cancer cells is crucial for improving patient outcomes. Here, we report a cell-line specific dependence on FANCI and related signaling pathways to counteract effects of DNA damaging chemotherapy in prostate cancer. Our results reveal that FANCI depletion results in significant downregulation of Fanconi anemia (FA) pathway members in prostate cancer cells indicating that FANCI is an important regulator of FA pathway. Furthermore, we found that FANCI silencing reduces proliferation in p53-expressing prostate cancer cells. This extends the evidence that inactivation of FANCI may convert cancer cells from a resistant to an eradicable state under the stress of DNA-damaging chemotherapy. Our results also indicate that high expression of FA pathway genes correlates with poorer survival in prostate cancer patients. Moreover, genomic alterations of FA pathway members are prevalent in prostate adenocarcinoma patients; mutation and copy number information for the FA pathway genes in seven patient cohorts (N = 1732 total tumor samples) reveals that 1025 (59.2%) tumor samples have an alteration in at least one of the FA pathway genes, suggesting that genomic alteration of the pathway is a prominent feature in patients with the disease. Citation Format: Heidi Kaljunen, Sinja Taavitsainen, Roosa Kaarijärvi, Eerika Takala, Ville Paakinaho, Matti Nykter, G. Steven Bova, Kirsi Ketola. FANCI regulates Fanconi anemia pathway and counteracts the effects of DNA damaging chemotherapy in prostate cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: DNA Damage Repair: From Basic Science to Future Clinical Application; 2024 Jan 9-11; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2024;84(1 Suppl):Abstract nr A025.

Development and validation of two nomograms for predicting overall survival and Cancer-specific survival in prostate cancer patients with bone metastases: a population-based study

BackgroundProstate cancer with bone metastasis has significant invasiveness and markedly poorer prognosis. The purpose of this study is to establish two nomograms for predicting the overall survival (OS) and cancer-specific survival (CSS) of prostate cancer patients with bone metastasis.MethodsFrom January 2000 to December 2018, a total of 2683 prostate adenocarcinoma with bone metastasis patients were identified from the Surveillance, Epidemiology, and End Results Program (SEER) database. These patients were then divided into a training cohort and a validation cohort, with OS and CSS as the study endpoints. Correlation analyses were employed to assess the relationship between variables. Univariate and multivariate Cox analyses were utilized to ascertain the independent prognostic factors. Calibration curves and the area under the time-dependent receiver operating characteristic curve (time-dependent AUC) were employed to evaluate discrimination and calibration of the nomogram. DCA was applied to examine accuracy and clinical benefits. The clinical utility of the nomogram and the AJCC Stage System was compared using net reclassification improvement (NRI) and integrated discrimination improvement (IDI). Lastly, the risk stratifications of the nomogram and the AJCC Stage System were compared.ResultsThere was no collinearity among the variables that were screened. The results of multivariate Cox regression analysis showed that seven variables (age, surgery, brain metastasis, liver metastasis, lung metastasis, Gleason score, marital status) and six variables (age, surgery, lung metastasis, liver metastasis, Gleason score, marital status) were identified to establish the nomogram for OS and CSS, respectively. The calibration curves, time-dependent AUC curves, and DCA revealed that both nomograms had pleasant predictive power. Furthermore, NRI and IDI confirmed that the nomogram outperformed the AJCC Stage System.ConclusionBoth nomograms had satisfactory accuracy and were validated to assist clinicians in evaluating the prognosis of PABM patients.

O03 - Complete biochemical response below 0.1 ng/ml predicts long-term therapy-free survival of prostate cancer patients treated with salvage lymph node dissection via PSMA-radioguided surgery

O03 - Complete biochemical response below 0.1 ng/ml predicts long-term therapy-free survival of prostate cancer patients treated with salvage lymph node dissection via PSMA-radioguided surgery

Fanconi anemia pathway regulation by FANCI in prostate cancer.

Prostate cancer is one of the leading causes of death among men worldwide, and thus, research on the genetic factors enabling the formation of treatment-resistant cancer cells is crucial for improving patient outcomes. Here, we report a cell line-specific dependence on FANCI and related signaling pathways to counteract the effects of DNA-damaging chemotherapy in prostate cancer. Our results reveal that FANCI depletion results in significant downregulation of Fanconi anemia (FA) pathway members in prostate cancer cells, indicating that FANCI is an important regulator of the FA pathway. Furthermore, we found that FANCI silencing reduces proliferation in p53-expressing prostate cancer cells. This extends the evidence that inactivation of FANCI may convert cancer cells from a resistant state to an eradicable state under the stress of DNA-damaging chemotherapy. Our results also indicate that high expression of FA pathway genes correlates with poorer survival in prostate cancer patients. Moreover, genomic alterations of FA pathway members are prevalent in prostate adenocarcinoma patients; mutation and copy number information for the FA pathway genes in seven patient cohorts (N = 1,732 total tumor samples) reveals that 1,025 (59.2%) tumor samples have an alteration in at least one of the FA pathway genes, suggesting that genomic alteration of the pathway is a prominent feature in patients with the disease.

Development of machine learning prognostic models for overall survival of prostate cancer patients with lymph node-positive

Prostate cancer (PCa) patients with lymph node involvement (LNI) constitute a single-risk group with varied prognoses. Existing studies on this group have focused solely on those who underwent prostatectomy (RP), using statistical models to predict prognosis. This study aimed to develop an easily accessible individual survival prediction tool based on multiple machine learning (ML) algorithms to predict survival probability for PCa patients with LNI. A total of 3280 PCa patients with LNI were identified from the Surveillance, Epidemiology, and End Results (SEER) database, covering the years 2000–2019. The primary endpoint was overall survival (OS). Gradient Boosting Survival Analysis (GBSA), Random Survival Forest (RSF), and Extra Survival Trees (EST) were used to develop prognosis models, which were compared to Cox regression. Discrimination was evaluated using the time-dependent areas under the receiver operating characteristic curve (time-dependent AUC) and the concordance index (c-index). Calibration was assessed using the time-dependent Brier score (time-dependent BS) and the integrated Brier score (IBS). Moreover, the beeswarm summary plot in SHAP (SHapley Additive exPlanations) was used to display the contribution of variables to the results. The 3280 patients were randomly split into a training cohort (n = 2624) and a validation cohort (n = 656). Nine variables including age at diagnosis, race, marital status, clinical T stage, prostate-specific antigen (PSA) level at diagnosis, Gleason Score (GS), number of positive lymph nodes, radical prostatectomy (RP), and radiotherapy (RT) were used to develop models. The mean time-dependent AUC for GBSA, RSF, and EST was 0.782 (95% confidence interval [CI] 0.779–0.783), 0.779 (95% CI 0.776–0.780), and 0.781 (95% CI 0.778–0.782), respectively, which were higher than the Cox regression model of 0.770 (95% CI 0.769–0.773). Additionally, all models demonstrated almost similar calibration, with low IBS. A web-based prediction tool was developed using the best-performing GBSA, which is accessible at https://pengzihexjtu-pca-n1.streamlit.app/. ML algorithms showed better performance compared with Cox regression and we developed a web-based tool, which may help to guide patient treatment and follow-up.

Immunohistochemistry-Based Biomarkers and Impact on Outcomes Following Salvage Radiotherapy for Prostate Cancer.

Salvage radiation therapy (SRT) is a mainstay of treatment for prostate cancer patients who experience biochemical relapse following radical prostatectomy. We sought to characterize the prognostic impact of previously identified deleterious molecular phenotypes-loss of PTEN, ERG expression, and p53 mutation- upon survival in patients undergoing SRT. We analyzed an institutional database of 320 patients treated with SRT for whom prostatectomy tissue was available; tissue microarrays (TMAs) were constructed and used for genetically validated immunohistochemistry assays for PTEN, ERG, and p53. Chi-squared and Mann-Whitney's tests were used to assess association between molecular expression and clinical risk factors for adverse survival. Uni- and multivariate Cox-proportional hazards models were constructed to determine effects on biochemical (bRFS) and metastasis-free survival (MFS), calculated from end of SRT to event. Loss of PTEN (n = 123, 50%) and ERG expression (n = 118, 39.1%) were common, while p53 overexpression (signifying TP53 missense mutation) was less common (n = 21, 6.6%). On univariate Cox regression, loss of PTEN portended worse bRFS [HR 1.86; 95% CI 1.36-2.57] and MFS [HR 1.89; 1.21-2.94], with homogeneous loss associated with particularly worse MFS [HR 2.47; 1.54-3.95]. Similarly, p53 overexpression predicted worse bRFS [HR 1.95; 1.14-3.32] and MFS [HR 2.79; 1.50-5.19]. ERG expression was associated with only worse MFS [HR 1.6; 1.03-2.48]. On multivariate analysis adjusting for known prognostic features (grade, nodal involvement, pathologic stage, androgen deprivation therapy (ADT), and PSA velocity), homogeneous PTEN loss remained predictive of adverse bRFS [HR 1.73; 1.06-2.82] and MFS [HR 2.35; 1.04-5.34]. PTEN loss identified by immunohistochemistry is an independent adverse prognostic factor for both biochemical and metastasis-free survival in prostate cancer patients treated with SRT. Although clinically validated RNA expression assays also exist which are prognostic for outcomes following SRT, stromal contamination in bulk RNA could mask "loss" signals specific to tumor cells, such as PTEN. Further work is necessary to determine the optimal approach to treating patients with poor molecular prognostic features in a salvage setting.

Senescence-associated secretory phenotype constructed detrimental and beneficial subtypes and prognostic index for prostate cancer patients undergoing radical prostatectomy

BackgroundCellular senescence is growing in popularity in cancer. A dual function is played by the senescence-associated secretory phenotype (SASP) that senescent cells produce in the development of pro-inflammatory niches, tissue regeneration or destruction, senescence propagation, and malignant transformation. In this study, we conducted thorough bioinformatic analysis and meta-analysis to discover detrimental and beneficial subtypes and prognostic index for prostate cancer (PCa) patients using the experimentally confirmed SASP genes.MethodsWe identified differentially expressed and prognosis-related SASP genes and used them to construct two molecular subtypes and risk score. Another two external cohorts were used to confirm the prognostic effect of the above subtypes and risk score and meta-analysis was further conducted. Additionally, functional analysis, tumor stemness and heterogeneity and tumor microenvironment were also evaluated. We completed analyses using software R 3.6.3 and its suitable packages. Meta-analysis was performed by software Stata 14.0.ResultsThrough multivariate Cox regression analysis and consensus clustering analysis, we used VGF, IGFBP3 and ANG to establish detrimental and beneficial subtypes in the TCGA cohort, which was validated through other two independent cohorts. Meta-analysis showed that detrimental SASP group had significantly higher risk of biochemical recurrence (BCR) than beneficial SASP group (HR: 2.48). Moreover, we also constructed and validated risk score based on these genes to better guide clinical practice. DNA repair, MYC target, oxidative phosphorylation, proteasome and ribosome were highly enriched in detrimental SASP group. Detrimental SASP group had significantly higher levels of B cells, CD8+ T cells, homologous recombination deficiency, loss of heterozygosity, microsatellite instability, purity, tumor mutation burden, mRNAsi, differentially methylated probes and epigenetically regulated RNA expression than beneficial SASP group. The top mutation genes between detrimental and beneficial SASP groups were SPOP, FOXA1, KMT2C, APC, BSN, DNAH17, MYH6, EPPK1, ZNF536 and ZC3H13 with statistical significance.ConclusionsFrom perspective of SASP, we found detrimental and beneficial tumor subtypes which were closely associated with BCR-free survival for PCa patients, which might be important for the furture research in the field of PCa.

Low Alanine Aminotransferase, as a Marker of Sarcopenia and Frailty, Is Associated with Shorter Survival Among Prostate Cancer Patients and Survivors. A Retrospective Cohort Analysis of 4064 Patients

BackgroundSarcopenia is characterized by loss of muscle mass and function and is associated with frailty, a syndrome with higher likelihood of falls, fractures, physical disability, and mortality. Both frailty and sarcopenia are known markers of shorter survival in various cancer patient populations. Low alanine aminotransferase (ALT), reflecting loss of muscle mass (sarcopenia), may be associated with greater frailty and shorter survival in multiple cancers. ObjectiveTo assess the potential association between low ALT and shorter survival among prostate cancer (PCa) patients and survivors. Design, setting, and participantsThis was a retrospective analysis of a historical cohort of PCa patients and survivors. Patients were defined as those still actively receiving PCa treatment, while those no longer receiving such treatment were classified as PCa survivors. Outcome measurements and statistical analysisALT data were obtained from results for basic biochemical blood testing carried out for patients on their first hospital admission. Patients were divided into two groups: those with ALT ≥17 IU/l and those with ALT <17 IU/l. Univariate and multivariable analyses were conducted for between-group survival comparisons. Results and limitationsWe identified 9489 PCa records. The final study cohort with ALT data available included 4064 patients with ALT <40 IU/l. Of this cohort, 536 patients were actively receiving medical anticancer therapy for PCa. The mean age for the entire cohort was 74.6 yr (standard deviation 9.6) and the median ALT level was 19.28 IU/l; 1676 patients (41%) had low ALT (<17 IU/l). On univariate analysis, low ALT was associated with a 78% increase in mortality risk (95% confidence interval [CI] 1.62–1.97; p < 0.001). A sensitivity analysis of the 536 patients actively receiving medical anticancer treatment revealed that low ALT was associated with a 48% increase in mortality risk (95% CI 1.19–1.85; p = 0.001). In a multivariable model controlled for age, kidney disease, history of cerebrovascular event/transient ischemic attack, and baseline prostate-specific antigen, low ALT was still associated with a 35% increase in mortality risk (95% CI 1.12–1.63; p = 0.001). Limitations include the single-center, retrospective design. ConclusionsLow ALT, which is indicative of sarcopenia and frailty, is associated with shorter survival among PCa patients and survivors and could potentially be used for treatment personalization. Patient summaryWe compared survival for prostate cancer patients and survivors according to their blood level of the protein alanine aminotransferase (ALT). Low ALT levels in the general population are associated with loss of muscle mass. We found that in our group of prostate cancer patients and survivors, the risk of death from any cause was higher for those with low ALT levels.

M6A-modified circABCC4 promotes stemness and metastasis of prostate cancer by recruiting IGF2BP2 to increase stability of CCAR1.

Prostate cancer (PCa) is a malignant tumor of the urinary system. CircABCC4 has been demonstrated to promote the development of PCa; however, its regulatory mechanisms in PCa progression remain largely unknown. We found that circABCC4 was highly expressed in PCa tissues and cells, and elevated circABCC4 level indicated a poor overall survival of PCa patients. METTL3 overexpression increased circABCC4 expression via m6A modification in PCa cells. Functionally, knockdown of circABCC4 or METTL3 repressed PCa cell stemness, migration, and invasion in vitro and delayed PCa cancer growth and metastasis in vivo. circABCC4 knockdown-mediated inhibition in PCa cell stemness and metastasis could be counteracted by overexpression of wild-type circABCC4 with m6A sites. Mechanistically, circABCC4 recruited IGF2BP2 protein to CCAR1 mRNA, thereby enhancing CCAR1 mRNA stability and subsequent activation of the Wnt/β-catenin pathway. Overexpression of CCAR1 counteracted the inhibitory effect of circABCC4 silencing on PCa cell stemness and metastasis. These results revealed that m6A-modified circABCC4 by METTL3 facilitated PCa cell stemness and metastasis by interacting with IGF2BP2 to increase the stability and expression of CCAR and subsequent expression of Wnt/β-catenin target genes. Our findings suggest circABCC4 as a promising therapeutic target for PCa.