ABSTRACT
PURPOSE: Currently, there are no accurate markers for predicting potentially lethal prostate cancer (PC) before biopsy. This study aimed to develop urine tests to predict clinically significant PC (sPC) in men at risk. METHODS: Urine samples from 928 men, namely, 660 PC patients and 268 benign subjects, were analyzed by gas chromatography/quadrupole time-of-flight mass spectrophotometry (GC/Q-TOF MS) metabolomic profiling to construct four predictive models. Model I discriminated between PC and benign cases. Models II, III, and GS, respectively, predicted sPC in those classified as having favorable intermediate risk or higher, unfavorable intermediate risk or higher (according to the National Comprehensive Cancer Network risk groupings), and a Gleason sum (GS) of ≥ 7. Multivariable logistic regression was used to evaluate the area under the receiver operating characteristic curves (AUC). RESULTS: In Models I, II, III, and GS, the best AUCs (0.94, 0.85, 0.82, and 0.80, respectively; training cohort, N = 603) involved 26, 24, 26, and 22 metabolites, respectively. The addition of five clinical risk factors (serum prostate-specific antigen, patient age, previous negative biopsy, digital rectal examination, and family history) significantly improved the AUCs of the models (0.95, 0.92, 0.92, and 0.87, respectively). At 90% sensitivity, 48%, 47%, 50%, and 36% of unnecessary biopsies could be avoided. These models were successfully validated against an independent validation cohort (N = 325). Decision curve analysis showed a significant clinical net benefit with each combined model at low threshold probabilities. Models II and III were more robust and clinically relevant than Model GS. CONCLUSION: This urine test, which combines urine metabolic markers and clinical factors, may be used to predict sPC and thereby inform the necessity of biopsy in men with an elevated PC risk.
Subject(s)
Metabolome , Prostatic Neoplasms , Humans , Male , Biopsy , Neoplasm Grading , Prostate-Specific Antigen , Prostatic Neoplasms/diagnosis , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/pathology , Prostatic Neoplasms/urine , Risk Factors , Early Detection of Cancer/methods , Urinalysis/methods , Urine/chemistryABSTRACT
Although prostate cancer (PC) is the most common cancer among men in the Western world, there are no good biomarkers that can reliably differentiate between potentially aggressive and indolent PC. This leads to overtreatment, even for patients who can be managed conservatively. Previous studies have suggested that nuclear lamin proteins-especially lamin B1 (LMNB1)-play important roles in PC progression. However, the results of these studies are inconsistent. Here, we transfected the LMNB1 gene into the telomerase reverse transcriptase-immortalized benign prostatic epithelial cell line, EP156T to generate a LMNB1-overexpressing EP156T (LMN-EP156T) cell line with increased cellular proliferation. However, LMN-EP156T cells could neither form colonies in soft agar, nor establish subcutaneous growth or metastasis in the xenograft NOD/SCID mouse model. In addition, immunohistochemical staining of LMNB1 in PC specimens from 143 patients showed a statistically significant trend of stronger LMNB1 staining with higher Gleason scores. A univariate analysis of the clinicopathological parameters of 85 patients with PC who underwent radical prostatectomy revealed that pathological stage, resection margin, and extracapsular extension were significant predictors for biochemical recurrence (BCR). However, LMNB1 staining showed only a non-significant trend of association with BCR (high vs. low staining: hazard ratio (HR), 1.83; 95% confidence interval (CI), 0.98-3.41; P = 0.059). In multivariate analysis, only pathological stage was a significant independent predictor of BCR (pT3 vs. pT2: HR, 2.29; 95% CI, 1.18-4.43; P = 0.014). In summary, LMNB1 may play a role in the early steps of PC progression, and additional molecular alterations may be needed to confer full malignancy potential to initiated cells.
ABSTRACT
Prostate cancer ranks the second in incidence and the fifth in mortality cancer in male globally. Citrus polymethoxyflavonoids (PMFs), such as tangeretin (PMF1), have been found to exhibit various biological activities. Here, we evaluated the inhibitory effects and mechanism of synthetic 5,4'-didemethyltangeretin (PMF2) on human prostate cancer LNCaP cells. We found that PMF2 inhibited the growth of LNCaP cells (GI50 14.6 µM) more strongly than PMF1, and it was less cytotoxic against the normal human prostate RWPE-1 cells. PMF2 upregulated Bad and Bax, downregulated Bcl-2, and activated caspase-3 and PARP in the LNCaP cells, thereby inducing apoptosis. PMF2 also suppressed the anchorage-independent growth of the LNCaP cells. It triggered p21 gene expression by demethylation of the p21 promoter region, and inhibited the protein expressions of DNMT 3B and HDACs 1, 2, and 4/5/9 by epigenetic regulations. We further found that PMF2 showed interactions with DNMTs 1, 2, and 3A ex vivo, which might inhibit DNMT activity. Additionally, PMF2 decreased the anchorage-independent growth of isolated LNCaP cancer stem-like cells (CSLCs) with high CD166 mRNA expression. These results indicated that PMF2 might inhibit the growth of human prostate cancer cells through different mechanisms, suggesting that PMF2 could be an innovative agent for prostate cancer therapy and prevention.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Cyclin-Dependent Kinase Inhibitor p21/genetics , Flavones/pharmacology , Prostatic Neoplasms/drug therapy , Apoptosis/drug effects , Cell Line, Tumor , Epigenesis, Genetic , Flavones/chemistry , Gene Expression Regulation, Neoplastic/drug effects , Humans , Male , Neoplastic Stem Cells/metabolism , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathologyABSTRACT
BACKGROUND: Caring for dying patients is an emotional burden for nurses. PURPOSE: This study used reflective groups to explore the process of transition that nurses go through in caring for dying patients. METHODS: We adopted a phenomenological approach. Data were collected from nurses participating in 12 reflective groups. All nurses worked in oncology / hospice units in a general hospital in Taipei. We used thematic analysis to analyze data. RESULTS: Findings identified a transition in how nurses handled and contained their emotions within three main themes: (1) containing unpredictable reality, (2) cautious "holding back" in discussion, and (3) self-cultivation in order to serve others. These findings led us to extrapolate the three issues of wounded healer, facing others, and altruism in caring. CONCLUSIONS/IMPLICATIONS FOR PRACTICE: This study represented the holding and containing of nurses in caring for dying patients and held group dialogues to facilitate reflection. Findings will be used to facilitate nurse self-awareness and improve end-of-life care quality.