Prostate cancer with elevated free prostate-specific antigen density:A case report

BACKGROUND Prostate cancer is the second most common cancer among men worldwide,and prostate-specific antigen(PSA)is often used in clinical practice to screen for prostate cancer.Normal total PSA(tPSA)level initially excludes prostate cancer.Here,we report a case of prostate cancer with elevated free PSA density(fPSAD).CASE SUMMARY A patient diagnosed with benign prostatic hyperplasia underwent prostatectomy,and the postoperative pathological results showed acinar adenocarcinoma of the prostate.The patient is currently undergoing endocrine chemotherapy.CONCLUSION We provide a clinical reference for diagnosis and treatment of patients with normal tPSA but elevated fPSAD.

Technetium-99m-methylene diphosphonate single photon emission computed tomography/computed tomography combined with prostate-specific antigen/free prostate-specific antigen ratio for bone metastasis of prostate cancer

BACKGROUND Prostate cancer(PC)is one of the most common malignant tumors in men,and bone metastasis is one of its common complications,which seriously affects the quality of life and prognosis of patients.AIM To investigate the diagnostic value of technetium-99m-methylene diphosphonate(99mTc-MDP)single photon emission computed tomography(SPECT)/CT imaging combined with the serum prostate-specific antigen(PSA)/free PSA ratio for PC bone metastasis(PCBM).METHODS One hundred patients with PC who visited the Hospital of Chengdu University of Traditional Chinese Medicine from January 2020 to January 2022 were recruited as the experimental(Exp)group,while 30 patients with benign prostatic lesions(BPLs)were recruited as the control(Ctrl)group.All patients underwent 99mTc-MDP SPECT/CT imaging and serum PSA/fPSA testing.The SPECT/CT imaging results and serum PSA/fPSA ratios of patients were analyzed to evaluate their diagnostic values for PCBM.RESULTS The difference in general information of the patients was not obvious,showing comparability.The two methods showed no visible differences in negative predictive value and sensitivity for patients with PCBM,but had great differences in positive predictive value and specificity(P<0.05).The PSA/fPSA ratio of patients with PC in the Exp group was lower than those with BPLs,and patients with PCBM had a much lower PSA/fPSA ratio than those without PC(P<0.05).The results confirmed that the combined use of 99mTc-MDP SPECT/CT imaging and serum PSA/fPSA ratio achieved a detection rate of 95%for PCBM.CONCLUSION The combination of 99mTc-MDP SPECT/CT and PSA/fPSA ratio is accurate and reliable for the diagnosis of PCBM,which provides an important reference for clinical practice.

Radioiodine therapy for castration-resistant prostate cancer following prostate-specific membrane antigen promoter-mediated transfer of the human sodium iodide symporter

Radioiodine therapy, the most effective form of systemic radiotherapy available, is currently useful only for thyroid cancer because of the thyroid-specific expression of the human sodium iodide symporter （hNIS）. Here, we explore the efficacy of a novel form of gene therapy using prostate-specific membrane antigen （PSMA） promoter-mediated hNIS gene transfer followed by radioiodine administration for the treatment of castration-resistant prostate cancer （CRPC）. The androgen-dependent C33 LNCaP cell line and the androgen-independent C81 LNCaP cell line were transfected by adenovirus. PSMA promoter-hNIS （Ad.PSMApro-hNIS） or adenovirus.cytomegalovirus-hNIS containing the cytomegalovirus promoter （Ad.CMM-hNIS） or a control virus. The iodide uptake was measured in vitro. The in vivo iodide uptake by C81 cell xenografts in nude mice injected with an adenovirus carrying the hNIS gene linked to PSMA and the corresponding tumor volume fluctuation were assessed. Iodide accumulation was shown in different LNCaP cell lines after Ad.PSMApro-hNIS and Ad.CMV-hNIS infection, but not in different LNCaP cell lines after adenovirus.cytomegalovirus （Ad.CMV） infection. At each time point, higher iodide uptake was shown in the C81 cells infected with Ad.PSMApro-hNIS than in the C33 cells （P 〈 0.05）. An in vivo animal model showed a significant difference in 1311 radioiodine uptake in the tumors infected with Ad.PSMApro-hNIS, Ad.CMV-hNIS and control virus （P 〈 0.05） and a maximum reduction of tumor volume in mice infected with Ad.PSMApro-hNIS. These results show prostate-specific expression of the hNIS gene delivered by the PSMA promoter and effective radioiodine therapy of CRPC by the PSMA promoter-driven hNIS transfection.

Prostate-specific membrane antigen expression in hepatocellular carcinoma,cholangiocarcinoma,and liver cirrhosis

BACKGROUND Primary liver cancer includes three subtypes:Hepatocellular carcinoma(HCC),intrahepatic cholangiocarcinoma(CCA),and combined hepatocellular carcinoma.Patients with primary liver cancer experienced poor prognosis and high mortality,so early detection of liver cancer and improved management of metastases are both key strategies to reduce the death toll from liver cancer.Prostate-specific membrane antigen(PSMA)expression in the tumor-associated neovasculature of nonprostate malignancies including liver cancer has been reported recently,but conclusive evidence of PSMA expression based on the pathological type of liver cancer remains limited.AIM To study the expression of PSMA in HCC,CCA,and liver cirrhosis.METHODS A total of 446 formalin-fixed paraffin-embedded(FFPE)liver tumor and liver cirrhosis tissue samples were obtained retrospectively from the Pathology Department of Tongji Hospital.Immunohistochemistry was used to detect PSMA expression in these 446 FFPE liver biopsy specimens(213 HCC,203 CCA,and 30 liver cirrhosis).The tumor compartment and the associated neovascular endothelium were separately analyzed.PSMA expression was examined by two certified pathologists,and the final results were presented in a 4-point scoring system(0-3 points).Correlation between PSMA expression and clinicopathological information was also assessed.RESULTS PSMA was expressed primarily in the neovascular endothelium associated with tumors.The positive rate of PSMA staining in HCC was significantly higher than that in CCA(86.8%vs 79.3%;P=0.001)but was only 6.6%in liver cirrhosis(P=0.000).HCC cases had more 3-score PSMA staining than CCA had(89/213,41.8%vs 35/203,17.2%;P=0.001).PSMA expression correlated positively with the stage and grade of HCC and CCA.In both liver cancer subtypes,there were more PSMA+cases in stages III–V diseases than in stages I and II.High staining intensity of PSMA was more frequently observed in liver cancers at high grade and advanced stage.There was no significant association of PSMA expression with sex,age,region,α-fetoprotein,hepatitis B surface antigen,or tumor size in both tumor subtypes.CONCLUSION Neovascular PSMA may be a promising marker to differentiate HCC from liver cirrhosis and a prognostic marker for anti-tumor angiogenesis therapy for HCC.

New frontiers in focal therapy for prostate cancer:Prostate-specific membrane antigen positron emission tomography/magnetic resonance imaging

Imaging has a central role in the context of focal therapy(FT)for prostate cancer(PCa).Prostate-specific membrane antigen(PSMA)positron emission tomography/magnetic resonance imaging(PET/MRI)is a novel imaging modality that combines the morpho-functional information of MRI with the molecular characterization of PET.Some papers reported the potential advantages of PSMA PET/MRI in different clinical scenarios.Limited evidence on PSMA PET/MRI is available in the setting of FT.PSMA PET/MRI can be an effective imaging modality for detecting primary PCa and seems to provide accurate local staging of primary PCa.PSMA PET/MRI also shows high performance for restaging and detecting tumor recurrence.The higher soft-tissue contrast and the reduction of ionizing radiation are the main advantages reported in the literature compared to PET/computed tomography.PSMA PET/MRI could represent a turning point in the management of patients with PCa in the context of FT.Further studies are needed to confirm its applications in this specific clinical setting.

Prostate-specific antigen reduction after capecitabine plus oxaliplatin chemotherapy:A case report

BACKGROUND Prostate cancer(PC)is currently the most common malignant tumor of the genitourinary system in men.Radical prostatectomy(RP)is recommended for the treatment of patients with localized PC.Adjuvant hormonal therapy(AHT)can be administered postoperatively in patients with high-risk or locally advanced PC.Chemotherapy is a vital remedy for castration-resistant prostate cancer(CRPC),and may also benefit patients with PC who have not progressed to CRPC.CASE SUMMARY A 68-year-old male was admitted to our hospital because of urinary irritation and dysuria with increased prostate-specific antigen(PSA)levels.After detailed examination,he was diagnosed with PC and treated with laparoscopic RP on August 3,2020.AHT using androgen deprivation therapy(ADT)was performed postoperatively because of the positive surgical margin,extracapsular extension,and neural invasion but lasted only 6 mo.Unfortunately,he was diagnosed with rectal cancer about half a year after self-cessation of AHT,and was then treated with laparoscopic radical rectal resection and adjuvant chemotherapy using the capecitabine plus oxaliplatin(CapeOx)regimen.During the entire treatment process,the patient's PSA level first declined significantly after treatment of PC with laparoscopic RP and ADT,then rebounded because of self-cessation of ADT,and finally decreased again after CapeOx chemotherapy.CONCLUSION CapeOx chemotherapy can reduce PSA levels in patients with high-risk locally advanced PC,indicating that CapeOx may be an alternative chemotherapy regimen for PC.

Association of Haplotypes in Exon 4 of KLK2 Gene with Raised Serum Prostate-Specific Antigen

The standard diagnostic modalities for Prostate Cancer (PC) include serum Prostate-Specific Antigen (PSA) assay, Digital Rectal Examination (DRE), and histological examination of prostate biopsy. They are limited by low predictive potential and inability to predict which patients are at risk of developing metastatic disease. The aim of this study is to investigate the exon 4 of the KLK2 gene of subjects for changes in its nucleotide sequences (SNPs) and determine the correlation of these changes with serum PSA in an Igbo population of Nigeria. One hundred male subjects aged 40 years and above, who gave their consent, were used for the study. Their PSA determinations were done using ELISA technique while genetic studies were carried out using real-time PCR. tPSA, fPSA, and % fPSA of the subjects ranged between 0.8% - 18.30%, 0.10% - 1.60% and 0.0% - 0.7% respectively. Of the 100 subjects, 28 subjects had tPSA levels above 4.0 ng/ml with a mean of 7.10 (±3.30) ng/ml. Those with tPSA less than 4 ng/ml had a mean of 1.87 (±0.85) ng/m. 15 subjects showed SNPs with a mean tPSA of 6.87 (±4.82) ng/ml while the remaining 85 subjects without SNPs had a mean of 1.86 (±0.80) ng/ml. Results from direct DNA sequencing showed 11 SNPs. Ten subjects are curated in SNP database while one is uncurated. The Chi-square test showed significant association (p = 0.00) between tPSA levels and SNPs mutation (X2 = 17.35, p = 0.00). A Kruskal-Wallis test demonstrated that the positional arrangement of the SNP mutations had no effect on PSA-total or free-values (H (10) = 10.92, p = 0.28;H (10) = 10.07, p = 0.38 respectively). Two SNPs: rs6072 and rs74478031 were associated with elevated PSA levels (p < 0.05). Their presence, therefore, has the potential to serve, in conjunction with raised PSA, as biomarkers of prostate cancer in the study population.

Measurement of Serum Total and Free Prostate-Specific Antigen for Breast Cancer Diagnosis in Women

Objective: To investigate the diagnostic value and the relationship between the clinicopathological features and the levels of total and free prostate-specific antigen (PSA) in women with breast cancer.Methods: Using the microparticle enzyme immunoassay system, we measured the concentrations of these markers in the sera of 85 women with breast cancer and in 30 healthy women.Rseults: The lowest detection level for both markers was 0.01 ng/ml. Free PSA levels were significantly higher in women with breast cancer than that in healthy women (P<0.05). The percentage of free PSA predominant subjects was 37.6% in breast cancer patients and 3.3% in healthy women. Cut-off values were 0.36 ng/ml for total PSA and 0.02 ng/ml for free PSA. In women with breast cancer, total PSA positivity was 23.5% and free PSA positivity was 27.1%. Compared to negatives, total PSA positive patients had a higher percentage of lymph node involvement tumours (P>0.05). However, patients with predominant free PSA had a higher percentage of early stage than patients with predominant PSA-ACT.Conclusion: Although the sensitivity of free PSA predominance is low (37.6%) in distinguishing women with breast cancer from healthy women, its specificity is high (97.0%).Free PSA predominance tends to be present in early stage tumours. These findings may indicate clinical significance of preoperative measurement of serum total and free PSA in women with breast cancer.

Prostate-specific antigen half-life： a new predictor of progression- free survival and overall survival in Chinese prostate cancer patients

We investigated the potential value of prostate-specific antigen half-life （PSAHL） and decreasing velocity （PSAVd） to predict progression-free survival （PFS） and overall survival （OS） in Chinese patients with prostate cancer. A total of 153 patients treated with hormonal therapy were included in the study. Of these, 78 patients progressed to hormone- refractory prostate cancer （HRPC） and 24 patients died by the end of follow-up. PSAHL was defined as the time during which prostate-specific antigen （PSA） concentration became half of the initial value during the first hormonal therapy. PSAVd reflected the decreasing velocity of PSA during the first hormonal therapy. PFS was defined as the interval from the beginning of hormonal therapy to HRPC. Cox proportional hazards regression analysis was used to evaluate whether PSAHL and PSAVd were significantly associated with PFS and OS. The median PSAHL and PSAVd were 0.50 months and 33.8 ng mL^-1 per month. The median PFS and OS were 22.7 months （95% confidence interval [CI], 22.0-29.6 months） and 43.5 months （95% CI, 37.9-48.4 months）, respectively. On univariate and multivariate analysis, long PSAHL （〉 0.5 months）, metastatic disease, high biopsy Gleason scores （〉 8） and high nadir PSA （〉 0.4 ng mL^-1） were all found to be significantly associated with short PFS. Long PSAHL, high nadir PSA and short PSA doubling time （PSADT 〈 2.0 months） were significantly associated with short OS. There were no significant relationships between PSAVd and either PFS or OS. Thus, PSAHL is a promising new independent predictor of survival. Patients with long PSAHL were identified as those at high risk for a relatively short PFS and OS.

A nomogram based on age, prostate-specific antigen level, prostate volume and digital rectal examination for predicting risk of prostate cancer

Nomograms for predicting the risk of prostate cancer developed using other populations may introduce sizable bias when applied to a Chinese cohort. In the present study, we sought to develop a nomogram for predicting the probability of a positive initial prostate biopsy in a Chinese population. A total of 535 Chinese men who underwent a prostatic biopsy for the detection of prostate cancer in the past decade with complete biopsy data were included. Stepwise logistic regression was used to determine the independent predictors of a positive initial biopsy. Age, prostate-specific antigen （PSA）, prostate volume （PV）, digital rectal examination （DRE） status, % free PSA and transrectal ultrasound （TRUS） findings were included in the analysis. A nomogram model was developed that was based on these independent predictors to calculate the probability of a positive initial prostate biopsy. A receiver-operating characteristic curve was used to assess the accuracy of using the nomogram and PSA levels alone for predicting positive prostate biopsy. The rate for positive initial prostate biopsy was 41.7% （223/535）. The independent variables used to predict a positive initial prostate biopsy were age, PSA, PV and DRE status. The areas under the receiver-operating characteristic curve for a positive initial prostate biopsy for PSA alone and the nomogram were 79.7% and 84.8%, respectively. Our results indicate that the risk of a positive initial prostate biopsy can be predicted to a satisfactory level in a Chinese population using our nomogram. The nomogram can be used to identify and counsel patients who should consider a prostate biopsy, ultimately enhancing accuracy in diagnosing prostate cancer.

Percent free prostate-specific antigen for prostate cancer diagnosis in Chinese men with a PSA of 4.0-10.0 ng/mL:Results from the Chinese Prostate Cancer Consortium

Objective:To test the diagnostic performance of percent free prostate-specific antigen(%fPSA)in predicting any prostate cancer(PCa)and high-grade prostate cancer(HGPCa)in a retrospective multi-center biopsy cohort with a PSA level of 4.0e10.0 ng/mL in China.Methods:Consecutive patients with a PSA of 4.0-10.0 ng/mL who underwent transrectal ultrasound-guided biopsy were enrolled at 16 Chinese medical centers from January 1st,2010 to December 31st,2013.Total and free serum PSA determinations were performed using three types of electro-chemiluminescence immunoassays recalibrated to the World Health Organization(WHO)standard.The diagnostic accuracy of PSA,%fPSA,and %fPSA in combination with PSA(%fPSA t PSA)was determined using the area under the receiver operating characteristic(ROC)curve(AUC).Results:A total of 2310 consecutive men with PSA levels between 4.0 and 10.0 ng/mL were included,and the detection rate of PCa was 25.1%.The AUC of%fPSA and %fPSA t PSA in predicting any PCa was superior to PSA alone in men aged≥60 years(0.623 vs.0.534,p<0.0001)but not in men aged 40e59 years(0.517 vs.0.518,p=0.939).Similar result was yield in predicting HGPCa.Conclusion:In a clinical setting of Chinese men with 4.0e10.0 ng/mL PSA undergoing initial prostate biopsy,adding %fPSA to PSA can moderately improve the diagnostic accuracy for any PCa and HGPCa compared with PSA alone in patients≥60 but not in patients aged 40-59 years.

Body mass index and serum lipid profile influence serum prostate-specific antigen in Chinese men younger than 50 years of age

This study is to assess the potential factors that could affect the serum prostate-specific antigen （PSA） level in healthy younger men. We evaluated the associations of age, body mass index （BMI） and serum lipid profile with serum PSA level in 6774 Chinese men （aged 20-49 years） who received a routine health examination. Eligible men were classified into 10-year age groups, BMI was categorized as underweight （〈18.5）, normal （18.5-22.9）, overweight （23.0-24.9）, obese （25.0-29,9） and very obese （〉30） according to the redefined World Health Organization （WHO） criteria for the Asia-Pacific region. PSA levels were compared among groups as well, In multiple linear regression analysis, PSA was positively correlated with age （P〈0.0001）. Negative correlations existed between PSA and BMI （P〈0.0001） and triglyceride level （P=0.01）. No relationship could be found between PSA and serum cholesterol （P=0.711） or high-density lipoprotein （HDL; P =0.665）. In addition, we found that serum PSA levels increased with age and decreased with BMI. Our study demonstrates that age, BMI and triglyceride levels influence the PSA level in men 〈50 years of age.

A biomimetic antitumor nanovaccine based on biocompatible calcium pyrophosphate and tumor cell membrane antigens

Currently,the cancer immunotherapy has made great progress while antitumor vaccine attracts substantial attention.Still,the selection of adjuvants as well as antigens are always the most crucial issues for better vaccination.In this study,we proposed a biomimetic antitumor nanovaccine based on biocompatible nanocarriers and tumor cell membrane antigens.Briefly,endogenous calcium pyrophosphate nanogranules with possible immune potentiating effect are designed and engineered,both as delivery vehicles and adjuvants.Then,these nanocarriers are coated with lipids and B16-OVA tumor cell membranes,so the biomembrane proteins can serve as tumor-specific antigens.It was found that calcium pyrophosphate nanogranules themselves were compatible and possessed adjuvant effect,while membrane proteins including tumor associated antigen were transferred onto the nanocarriers.It was demonstrated that such a biomimetic nanovaccine could be well endocytosed by dendritic cells,promote their maturation and antigen-presentation,facilitate lymph retention,and trigger obvious immune response.It was confirmed that the biomimetic vaccine could induce strong T-cell response,exhibit excellent tumor therapy and prophylactic effects,and simultaneously possess nice biocompatibility.In general,the present investigation might provide insights for the further design and application of antitumor vaccines.

Serum prostate-specific antigen as a predictor of prostate volume and lower urinary tract symptoms in acommunity-based cohort： a large-scale Korean screening study

The aim of this study is to assess the ability of serum prostate-specific antigen （PSA） to predict prostate volume （PV） and lower urinary tract symptoms （LUTS） represented by the international prostate symptom score （IPSS）. From January 2001 to December 2011, data were collected from men who first enrolled in the Korean Prostate Health Council Screening Program. Patients with a serum PSA level of 10 ng ml^-1 or age 〈40 years were excluded. Accordingly, a total of 34 857 men were included in our study, and serum PSA, PV and the IPSS were estimated in all patients. Linear and age-adjusted multivariate logistic analyses were used to assess the potential association between PSA and PV or IPSS. The predictive value of PSA for estimating PV and IPSS was assessed based on the receiver operating characteristics-derived area under the curve （AUC）. The mean PV was 29.9 ml, mean PSA level was 1.49 ng ml^-1 and mean IPSS was 15.4. A significant relationship was shown between PSA and PV, and the IPSS and PSA were also significantly correlated after adjusting by age. The AUCs of PSA for predicting PV ~20 ml, 〉25 ml and 〉35 ml were 0.722, 0.728 and 0.779, respectively. The AUCs of PSA for predicting IPSS 〉 7, 〉 13 and 〉 19 were 0. 548, 0.536 and 0. 537, respectively. Serum PSA was a strong predictor of PV in a community-based cohort in a large-scale screening study. Although PSA was also significantly correlated with IPSS, predictive values of PSA for IPSS above the cutoff levels were not excellent. Further investigations are required to elucidate the exact interactions between PSA and LUTS and between PSA and PV in prospective controlled studies. Such studies may suggest how PSA can be used to clinically predict PV and the IPSS.

Relationship between insulin resistance, obesity and serum prostate-specific antigen levels in healthy men

The purpose of this study was to determine the relationship between insulin resistance, obesity and serum prostate-specific antigen （PSA） levels in healthy men with serum PSA level below 4 ng mL-1. The men included in the study cohort were 11 827 healthy male employees of the Korea Hydro and Nuclear Power Co., LTD who had undergone medical checkups including fasting glucose, fasting insulin and serum PSA between January 2003 and December 2008. Insulin resistance was calculated by homeostasis model assessment （HOMA [fasting glucose × fasting insulin]/22.5） and quantitative insulin sensitivity check index （QUICK/; 1/[log （fasting insulin） ＋ log （fasting glucose）]）. Age-adjusted body mass index （BMI） was significantly increased according to increasing quartile of insulin resistance as determined by HOMA and QUICKI, respectively, in analysis of variance （ANOVA） test and Duncan＇s multiple comparison test （P 〈 0.001）, but age-adjusted serum PSA concentration was significantly decreased according to increasing quartile of insulin resistance as determined by HOMA and QUICK/（P 〈 0.001）. Age, BMI, insulin resistance by HOMA or QUICK/were significantly independent variables to serum PSA level in a multivariate linear regression analysis （P 〈 0.001）. Insulin resistance was a significant independent variable to serum PSA level along with BMI. Insulin resistance and BMI were negatively correlated with serum PSA level in healthy men. Insulin resistance was positively correlated with BMI.

Decreasing trend in prostate cancer with high serum prostate-specific antigen levels detected at first prostate-specific antigen-based population screening in Japan

To clarify the recent trends in prostate-specific antigen （PSA） distribution in men in Japan, we analyzed the PSA distributions of men undergoing PSA-based population screening. We summarized the annual individual data of PSA-based population screening in Kanazawa, Japan, from 2000 to 2011, and analyzed baseline serum PSA values of the participants at the first population screening. Serum PSA distributions were estimated in all participants and those excluding prostate cancer patients according to age. From 2000 to 2011, 19 620 men participated aged 54-69 years old in this screening program. Mean baseline serum PSA level of all participants at the first screening was 2.64 ng m1-1 in 2000, and gradually decreased to approximately 1.30 ng ml-I in 2006. That of participants excluding prostate cancer patients was 1.46 ng m1-1 in 2000, and there was no remarkable change during the study period. The 95t＂ percentiles in the participants excluding prostate cancer patients detected at the first population screening of men aged 54-59, 60-64, and 65-69 years old were 2.90, 3.60, and 4.50 ng m1-1, respectively. After the commencement of population screening, the proportion of prostate cancer patients with high serum PSA levels decreased. However, there were no changes in serum PSA levels in men without prostate cancer. Age-specific PSA reference level of men without prostate cancer in Japan was similar to that in China and Korea.

Serum testosterone and prostate-specific antigen levels are major risk factors for prostatic volume increase among benign prostatic hyperplasia patients

Objective:Benign prostatic hyperplasia(BPH)is one of the most common diseases found among elderly men.Even though multiple risk factors of BPH have been identified in the past,the risk factors which have a direct impact on prostate volume have not been identified.In this study,we aim to determine the most significant contributing risk factors to prostate volume enlargement by analyzing possible associated risk factors previously studied.Methods:This is a quantitative study with an analytical observational design,performed using a retrospective cohort approach.Total sampling was performed on 83 patients who underwent transurethral resection of the prostate(TURP)in Sanglah General Hospital from January to February 2019.Bivariate analysis is performed to examine each variable's association with prostate volume followed by a multivariate analysis.All variables were reassessed with path analysis to measure the direct effects,indirect effects,and total effects on prostate volume.Results:Bivariate analysis shows that serum testosterone(R=0.208;p=0.059)and prostate-specific antigen(PSA)level(R=0.626;p=0.001)have a significant association with prostate volume.Multivariate analysis shows that serum PSA(B=1.4;p=0.001;95%confidence interval[95%CI]=1.039-1.770)and testosterone(B=0.024;p=0.005;95%CI=0.008-0.041)levels are significant among all the analyzed risk factors.There is a significant and strong effect of PSA to prostate volume(c=0.636;p=0.001)whereas testosterone has a significant albeit weak effect to prostate volume(c=0.246;p=0.009)based on the total effect of the path analysis.Conclusion:Serum testosterone and PSA levels are significantly associated with prostatic volume increase among BPH patients.

Prostate-specific antigen kallikrein and the heart

Currently,there is growing interest regarding prostatespecific antigen(PSA) and the cardiovascular system.Increased PSA serum levels have been reported after prolonged cardiopulmonary resuscitation,cardiac surgery,extracorporeal cardiopulmonary bypass,acute myocardial infarction(AMI) and coronary artery stenting.The possible role of PSA in cardiac events has been questioned due to the finding of PSA decrease during AMI and by the correlation of variation in PSA levels with coronary lesions and occurrence of major adverse cardiac events.Complexed PSA forms and uncomplexed PSA forms are observed in the bloodstream but the increasing formation of irreversible bound PSA seems to be a crucial finding during AMI.Large studies need to be carried out to confirm these preliminary results and to elucidate unclear aspects.These findings present many potential directions for future research including the role of uncomplexed forms of PSA,the possible distribution of PSA in the heart,the relative expression levels in heart disease states,the mode of expression regulation and other potential specific substrates.The journey of PSA investigation could be longer than initially expected.

Determination of the genus-specific antigens in outer membrane proteins from the strains of Leptospira interrogans and Leptospira biflexa with different virulence

Objective:To determine the existence of genus-specific antigens in outer membrane proteins (OMPs) of leptospira with different virulence. Methods: Microscope agglutination test (MAT) was applied to detect the agglutination between commercial rabbit antiserum against leptospiral genus-specific TR/Patoc I antigen and 17 strains of Leptospira interrongans belonging to 15 serogroups and 2 strains of Leptospira biflexa belonging to 2 serogroups.The outer envelopes (OEs) of L.interrogans serogroup Icterohaemorrhagiae serovar lai strain lai (56601) with strong virulence and serogroup Pomona serovar pomona strain Luo (56608) with low virulence,and L.biflexa serogroup Semaranga serovar patoc strain Patoc I without virulence were prepared by using the method reported in Auran et al.(1972).OMPs in the OEs were obtained by treatment with sodium deoxycholate. SDS-PAGE and western blot were used for analyzing the features of the OMPs on electrophoretic pattern and the immunoreactivity to the antiserum against TR/Patoc I antigen, respectively. Results:All the tested strains belonging to different leptospiral serogroups agglutinated to the antiserum against leptospiral genus-specific TR/Patoc I antigen with agglutination titers ranging from 1:256-1:512. A similar SDS-PAGE pattern of the OMPs from the three strains of leptospira with different virulence was shown and the molecular weight of a major protein fragment in the OMPs was found to be approximately 60 KDa.A positive protein fragment with approximately 32 KDa confirmed by Western blot,was able to react with the antiserum against leptospiral genus-specific TR/Patoc I antigen, and was found in each the OMPs of the three stains of leptospira.Conclusion: There are genus-specific antigens on the surface of L.interrogans and L.biflexa. The OMP with molecular weight of 32 KDa may be one of the genus-specific protein antigens of leptospira.

A population study of fasting time and serum prostate-specific antigen （PSA） level

Prostate cancer is one of the most common cancers in men. Traditional screening and diagnostic methods include digital rectal examinations （DREs）, biopsies and serum prostate-specific antigen （PSA） tests, with the latter being the more popular. PSA is a biomarker for prostate cancer; however, it is highly sensitive to external factors as well as other prostate diseases. As such, the reliability of of the serum PSA level as a sole screening and diagnostic tool for prostate cancer is controversial. Recently, it has been shown that fasting extremes can affect concentrations of serum chemistry analytes, thus raising the question of whether or not fasting has an effect on the highly sensitive PSA biomarker. Patients testing for serum PSA levels are often concomitantly submitting to other tests that require fasting, subjecting certain patients to a fasting PSA level while others not. The objective of this study was to investigate whether this discrepancy in fasting state translates into an effect on serum PSA levels. Serum PSA levels and fasting time records for 157 276 men who underwent testing at Calgary Laboratory Services （CLS; Calgary, Alberta, Canada） between 01 January 2010 and 31 March 2013 were accessed. Linear regression models of mean PSA levels and fasting times revealed a statistically important relationship at certain fasting times. Applying a dynamic mathematical model to explore the clinical effect of fasting suggests minimal impact on serum PSA result interpretation. Thus, patients can be tested for serum PSA levels regardless of their fasting state.