Evaluation of an immunochromatography-based rapid antigen test, Inspecter Kowa® SARS-CoV-2, using saliva specimens for the detection of SARS-CoV-2.

BACKGROUND: In the context of the coronavirus disease 2019 (COVID-19) pandemic, a rapid and reliable point-of-care test is an essential tool for controlling the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In particular, an immunochromatography test (ICT) that uses saliva specimens for rapid antigen detection not only reduces the risk of secondary infections but also reduces the burden on medical personnel. METHODS: The newly developed salivary antigen test kit "Inspecter Kowa® SARS-CoV-2" is an ICT to which saliva specimens can be directly applied. We evaluated its usefulness in comparison with reverse transcription quantitative PCR (RT-qPCR) and the Espline® SARS-CoV-2 Kit for the detection of SARS-CoV-2 using nasopharyngeal swab specimens. In this study, 140 patients with suspected symptomatic COVID-19 who visited our hospital were enrolled, and nasopharyngeal swab and saliva specimens were collected after they consented to participate in the study. RESULTS: Inspector Kowa SARS-CoV-2 was positive in 45 of 61 (73.8%) saliva that were positive by RT-qPCR and the Espline® SARS-CoV-2 Kit was also positive in 56 of 60 (93.3%) Np swabs that were positive by RT-qPCR. Good antigen detection was achieved by ICT with saliva and nasopharyngeal swab specimens when viral load was ≥105 copies/mL, whereas detection sensitivity was low when viral load was <105 copies/mL, especially in saliva specimens. CONCLUSION: This ICT for the detection of SARS-CoV-2 salivary antigen is an attractive tool that does not require specialized equipment and allows patients to perform the entire process from sample collection to self-diagnose and to reduce the burden on medical care during a pandemic.

[Testicular Malignant Sertoli Cell Tumor with Long-Term Survival After Pulmonary Metastasectomy: A Case Report].

A 45-year-old man was referred to our hospital with a complaint of right scrotal discomfort. With a diagnosis of testicular tumor, right orchiectomy was performed. The tumor was histologically diagnosed as malignant Sertoli cell tumor pT1N0M0. A pulmonary nodule appeared, 53 months after the operation, and increased in size there after. Thoracoscopic left upper lobectomy was performed 64 months after the operation, and the pathological diagnosis was metastasis of malignant Sertoli cell tumor. No recurrence has been observed for 94 months after the resection of the metastatic lesion.

Establishment and characterization of a novel treatment-related neuroendocrine prostate cancer cell line KUCaP13.

The prevalence of neuroendocrine prostate cancer (NEPC) arising from adenocarcinoma (AC) upon potent androgen receptor (AR) pathway inhibition is increasing. Deeper understanding of NEPC biology and development of novel therapeutic agents are needed. However, research is hindered by the paucity of research models, especially cell lines developed from NEPC patients. We established a novel NEPC cell line, KUCaP13, from tissue of a patient initially diagnosed with AC which later recurred as NEPC. The cell line has been maintained permanently in vitro under regular cell culture conditions and is amenable to gene engineering with lentivirus. KUCaP13 cells lack the expression of AR and overexpress NEPC-associated genes, including SOX2, EZH2, AURKA, PEG10, POU3F2, ENO2, and FOXA2. Importantly, the cell line maintains the homozygous deletion of CHD1, which was confirmed in the primary AC of the index patient. Loss of heterozygosity of TP53 and PTEN, and an allelic loss of RB1 with a transcriptomic signature compatible with Rb pathway aberration were revealed. Knockdown of PEG10 using shRNA significantly suppressed growth in vivo. Introduction of luciferase allowed serial monitoring of cells implanted orthotopically or in the renal subcapsule. Although H3K27me was reduced by EZH2 inhibition, reversion to AC was not observed. KUCaP13 is the first patient-derived, treatment-related NEPC cell line with triple loss of tumor suppressors critical for NEPC development through lineage plasticity. It could be valuable in research to deepen the understanding of NEPC.

Downregulation of RalGTPase-activating protein promotes invasion of prostatic epithelial cells and progression from intraepithelial neoplasia to cancer during prostate carcinogenesis.

RalGTPase-activating protein (RalGAP) is an important negative regulator of small GTPases RalA/B that mediates various oncogenic signaling pathways in various cancers. Although the Ral pathway has been implicated in prostate cancer (PCa) development and progression, the significance of RalGAP in PCa has been largely unknown. We examined RalGAPα2 expression using immunohistochemistry on two independent tissue microarray sets. Both datasets demonstrated that the expression of RalGAPα2 was significantly downregulated in PCa tissues compared to adjacent benign prostatic epithelia. Silencing of RalGAPα2 by short hairpin RNA enhanced migration and invasion abilities of benign and malignant prostate epithelial cell lines without affecting cell proliferation. Exogenous expression of wild-type RalGAP, but not the GTPase-activating protein activity-deficient mutant of RalGAP, suppressed migration and invasion of multiple PCa cell lines and was phenocopied by pharmacological inhibition of RalA/B. Loss of Ralgapa2 promoted local microscopic invasion of prostatic intraepithelial neoplasia without affecting tumor growth in a Pten-deficient mouse model for prostate tumorigenesis. Our findings demonstrate the functional significance of RalGAP downregulation to promote invasion ability, which is a property necessary for prostate carcinogenesis. Thus, loss of RalGAP function has a distinct role in promoting progression from prostatic intraepithelial neoplasia to invasive adenocarcinoma.

[Delay in High-Grade Metastatic Prostate Cancer Progression by Dutasteride : A Case Report].

An 84-year-old man was referred to our hospital with swollen right cervical lymph nodes. Computed tomography showed right supraclavicular and mediastinal lymph node enlargement, and fluorodeoxyglucose positronemissiontomography showed multiple areas of abnormally increased radioactivity inthe right supraclavicular and mediastinal lymph nodes, right ninth rib, and left fifth and seventh ribs. Biopsy of the right supraclavicular lymph node revealed metastatic adenocarcinoma with partial immunohistochemical staining for prostate specific antigen (PSA). Serum PSA levels were not elevated (2.01 ng/ml). An 8-core transrectal prostatic biopsy was negative. Thus, we could not determine the primary site of the adenocarcinoma. The patient was diagnosed with carcinoma of an unknown primary site and followed without chemotherapy. Four years later, he was referred to our hospital due to right hydronephrosis. Serum PSA level was 31. 1 ng/ml. The tumor was not palpable by rectal examination. A 12-core transrectal prostatic biopsy revealed a poorly differentiated adenocarcinoma. Computed tomography revealed metastases in the left axilla, para-aortic, and pelvic lymph nodes as well as in the lung. We diagnosed the patient with prostate cancer, and combined androgen blockade (CAB) was administered. Metastases in the lymph nodes, lung, and bone were reduced on imaging after 1 month of therapy. Therefore, a definitive diagnosis of prostate cancer T1cN1M1c was made. Dutasteride had been administered as a benign prostate hyperplasia treatment 2 years before his first visit, which may have made the definitive diagnosis of prostate cancer difficult. In contrast, dutasteride may have delayed the progressionof prostate cancer inthis patient.

[A Case of Seminal Vesicle Cyst Incidentally Diagnosed during Rupture of Abdominal Subcutaneous Abscess].

Seminal vesicle cyst is a rare disease and is often asymptomatic. We present a case of huge seminal vesicle cyst connected to the abdominal wall and observed as a subcutaneous abscess. An 89-year-old man presented with asymptomatic spontaneous rupture of the left lower abdominal subcutaneous abscess. Computed tomography (CT) showed a relatively low intensity cystic mass located in the Retzius' space just below the abscess, surrounding the right bladder wall laterally and connecting to the right seminal vesicle posteriorly. Biopsy of the skin around the subcutaneous abscess and aspiration biopsy of the pelvic cystic fluid showed no evidence of malignancy. We diagnosed the lesion as a seminal vesicle cyst with bacterial infection. The patient was treated with antibiotics and there has been no relapse.

[False Elevation of Prostate-Specific Antigen Caused by Heterophilic Antibody Interference after Radical Prostatectomy : A Case Report].

We described a 63-year-old man who was diagnosed with clinical T1c prostate cancer, with a Gleason score of 6 (3＋3), and a preoperative prostate-specific antigen (PSA) level of 5. 27 ng/ml. Radical prostatectomy(RP) was performed and final pathologyshowed Gleason score 3＋4, pT2c with negative surgical margin. In spite of suggested surgical radicality, PSA was 3.32, 4.78, 5.93 ng/ml, at 1, 2, and 3 months after RP, respectively. However, radiological investigation revealed no metastasis. Because of this clinical discrepancy, we checked the PSA-α1-antichemotrypsin level and found it to be ≦0.1 ng/ml. From these results, false PSA elevation caused byinterference of positive heterophilic antibodies was suggested and demonstrated byseveral immunoassays.

[A Crossover Comparison Study on Lower Urinary Tract Symptoms with Overactive Bladder Secondary to Benign Prostatic Hyperplasia: Naftopidil versus Tamsulosin with Solifenacin].

We compared the efficacy of naftopidil monotherapy with combination therapy using tamsulosin hydrochloride and solifenacin succinate in the treatment of lower urinary tract symptoms (LUTS) with overactive bladder (OAB) secondary to benign prostatic hyperplasia (BPH). Thirty one patients were enrolled in a randomized crossover study. Fourteen patients were initially prescribed naftopidil 75 mg (N) for 8 weeks, followed by tamsulosin 0.2 mg and solifenacin 5 mg (TS) for 8 weeks (group N) ; another 17 were initially prescribed TS, followed by N (group TS). The efficacy variables were the changes in international prostate symptom score (I-PSS), quality of life (QOL) score, overative bladder symptom score (OABSS), and post-void residual (PVR) urine volume. After the study, a questionnaire survey was carried out about the choice of treatment. After treatment with each agent, total I-PSS, storage symptom score, QOL score and OABSS except for the daytime frequency were significantly improved from baseline. PVR was significantly increased after TS treatment. There were no significant differences between the two treatments except for PVR. As a result of the questionnaire survey, 13 patients chose N and 17 chose TS. In conclusion, N monotherapy can be expected to have an equal effect in the treatment of LUTS with OAB secondary to BPH in comparison with TS combination therapy.

Identification of the α2 chain of interleukin-13 receptor as a potential biomarker for predicting castration resistance of prostate cancer using patient-derived xenograft models.

BACKGROUND: Several treatment strategies use upfront chemotherapy or androgen receptor axis-targeting therapies for metastatic prostate cancer. However, there are no useful biomarkers for selecting appropriate patients who urgently require these treatments. METHODS: Novel patient-derived xenograft (PDX) castration-sensitive and -resistant models were established and gene expression patterns were comprehensively compared. The function of a gene highly expressed in the castration-resistant models was evaluated by its overexpression in LNCaP prostate cancer cells. Protein expression in the tumors and serum of patients was examined by immunohistochemistry and ELISA, and correlations with castration resistance were analyzed. RESULTS: Expression of the α2 chain of interleukin-13 receptor (IL13Rα2) was higher in castration-resistant PDX tumors. LNCaP cells overexpressing IL13Rα2 acquired castration resistance in vitro and in vivo. In tissue samples, IL13Rα2 expression levels were significantly associated with castration-resistant progression (p < 0.05). In serum samples, IL13Rα2 levels could be measured in 5 of 28 (18%) castration-resistant prostate cancer patients. CONCLUSION: IL13Rα2 was highly expressed in castration-resistant prostate cancer PDX models and was associated with the castration resistance of prostate cancer cells. It might be a potential tissue and serum biomarker for predicting castration resistance in prostate cancer patients.

[Long-term disease stabilization by Strontium 89 (89Sr) for castration and docetaxel-resistant prostate cancer : a case report].

A 67-year old man was diagnosed with advanced prostate cancer with multiple pelvic lymph nodes and multiple bone metastases (cT2N1M1b), with an initial prostate specific antigen of 1,300 ng/ml. Prostate biopsy specimens revealed poorly differentiated adenocarcinoma, Gleason's score 5＋3. He was treated with maximal androgen blockade (MAB) from 2001, but showed resistance to hormone therapy and docetaxel in 2007. External radiation therapy for bone pain was difficult due to multiple lesions. 89Sr therapy was started in 2009. The therapy could be performed 5 times without any side effects. Good pain control and decreasing PSA was obtained at each dose.

Comprehensive genomics in androgen receptor-dependent castration-resistant prostate cancer identifies an adaptation pathway mediated by opioid receptor kappa 1.

Castration resistance is a lethal form of treatment failure of prostate cancer (PCa) and is associated with ligand-independent activation of the androgen receptor (AR). It is only partially understood how the AR mediates survival and castration-resistant growth of PCa upon androgen deprivation. We investigated integrative genomics using a patient-derived xenograft model recapitulating acquired, AR-dependent castration-resistant PCa (CRPC). Sequencing of chromatin immunoprecipitation using an anti-AR antibody (AR-ChIP seq) revealed distinct profiles of AR binding site (ARBS) in androgen-dependent and castration-resistant xenograft tumors compared with those previously reported based on human PCa cells or tumor tissues. An integrative genetic analysis identified several AR-target genes associated with CRPC progression including OPRK1, which harbors ARBS and was upregulated upon androgen deprivation. Loss of function of OPRK1 retarded the acquisition of castration resistance and inhibited castration-resistant growth of PCa both in vitro and in vivo. Immunohistochemical analysis showed that expression of OPRK1, a G protein-coupled receptor, was upregulated in human prostate cancer tissues after preoperative androgen derivation or CRPC progression. These data suggest that OPRK1 is involved in post-castration survival and cellular adaptation process toward castration-resistant progression of PCa, accelerating the clinical implementation of ORPK1-targeting therapy in the management of this lethal disease.

[Complete response of lung metastasis to interferon-alpha therapy after radical nephrectomy for sarcomatoid renal cell carcinoma with Stauffer syndrome: a case report].

A 75-year-old man was admitted to our hospital with liver dysfunction and elevated C-reactive protein level. He was diagnosed with renal tumor by ultrasonography. Computed tomography revealed a renal cell carcinoma (cT3aN0M0) with Stauffer syndrome. Laparoscopic radical nephrectomy was performed. Histological findings indicated clear cell carcinoma with a sarcomatoid component. After 1 month, lung metastasis was detected on an X-ray film. Interferon-α was administered, and complete response was achieved 2 months later. He has shown no evidence of recurrence in 27 months.

Clinical Impact of Detecting Low-Frequency Variants in Cell-Free DNA on Treatment of Castration-Resistant Prostate Cancer.

PURPOSE: Although cell-free DNA (cfDNA) testing is expected to drive cancer precision medicine, little is known about the significance of detecting low-frequency variants in circulating cell-free tumor DNA (ctDNA) in castration-resistant prostate cancer (CRPC). We aimed to identify genomic profile including low-frequency variants in ctDNA from patients with CRPC and investigate the clinical utility of detecting variants with variant allele frequency (VAF) below 1%. EXPERIMENTAL DESIGN: This prospective, multicenter cohort study enrolled patients with CRPC eligible for treatment with abiraterone or enzalutamide. We performed targeted sequencing of pretreatment cfDNA and paired leukocyte DNA with molecular barcodes, and ctDNA variants with a VAF ≥0.1% were detected using an in-house pipeline. We investigated progression-free survival (PFS) and overall survival (OS) after different ctDNA fraction cutoffs were applied. RESULTS: One hundred patients were analyzed (median follow-up 10.7 months). We detected deleterious ATM, BRCA2, and TP53 variants even in samples with ctDNA fraction below 2%. When the ctDNA fraction cutoff value of 0.4% was applied, significant differences in PFS and OS were found between patients with and without defects in ATM or BRCA2 [HR, 2.52; 95% confidence interval (CI), 1.24-5.11; P = 0.0091] and TP53 (HR, 3.74; 95% CI, 1.60-8.71; P = 0.0014). However, these differences were no longer observed when the ctDNA fraction cutoff value of 2% was applied, and approximately 50% of the samples were classified as ctDNA unquantifiable. CONCLUSIONS: Detecting low-frequency ctDNA variants with a VAF <1% is important to identify clinically informative genomic alterations in CRPC.

A Prospective Randomized Trial Comparing a Combined Regimen of Amikacin and Levofloxacin to Levofloxacin Alone as Prophylaxis in Transrectal Prostate Needle Biopsy.

PURPOSE: We investigated whether addition of amikacin to levofloxacin-based antimicrobial prophylaxis reduces febrile urinary tract infections after transrectal ultrasound-guided prostate needle biopsy (TRUSB). MATERIALS AND METHODS: A total of 447 patients undergoing TRUSB were prospectively randomized into two groups. The 230 patients in Group A were given one oral dose of levofloxacin 400 mg prior to TRUSB; the 217 patients in Group B each received the same dose of levofloxacin and one 200 mg intravenous dose of amikacin. Patients' characteristics were assessed prior to TRUSB and their symptoms were checked after the TRUSB. RESULTS: Both regimens were well tolerated with no side effects. No statistically significant difference in patients' characteristics, or in incidence of inflammation- or infection-related symptoms was seen between the two groups; nor any significant difference among those who developed fever and those who did not. Two Group A patients and one Group B patient developed febrile urinary tract infections. Accountable pathogens determined by urine and blood cultures were fluoroquinolone-resistant E.coli and extended-spectrum ß-lactamase-producing E.coli. All pathogens isolated were levofloxacin-resistant, amikacin-susceptible species. CONCLUSION: Although the present study was under-powered by unexpectedly low overall incidence of febrile urinary tract infections, addition of one intravenous administration of amikacin to one oral administration of levofloxacin showed no advantage compared with levofloxacin alone as antimicrobial prophylaxis in TRUSB. Strikingly, all pathogens isolated from febrile patients were sensitive to amikacin in vitro. Therefore, further understanding of amikacin's drug kinetics in the prostate is necessary to develop a more efficient drug delivery system for amikacin.