IDH2 stabilizes HIF-1α-induced metabolic reprogramming and promotes chemoresistance in urothelial cancer.

Drug resistance contributes to poor therapeutic response in urothelial carcinoma (UC). Metabolomic analysis suggested metabolic reprogramming in gemcitabine-resistant urothelial carcinoma cells, whereby increased aerobic glycolysis and metabolic stimulation of the pentose phosphate pathway (PPP) promoted pyrimidine biosynthesis to increase the production of the gemcitabine competitor deoxycytidine triphosphate (dCTP) that diminishes its therapeutic effect. Furthermore, we observed that gain-of-function of isocitrate dehydrogenase 2 (IDH2) induced reductive glutamine metabolism to stabilize Hif-1α expression and consequently stimulate aerobic glycolysis and PPP bypass in gemcitabine-resistant UC cells. Interestingly, IDH2-mediated metabolic reprogramming also caused cross resistance to CDDP, by elevating the antioxidant defense via increased NADPH and glutathione production. Downregulation or pharmacological suppression of IDH2 restored chemosensitivity. Since the expression of key metabolic enzymes, such as TIGAR, TKT, and CTPS1, were affected by IDH2-mediated metabolic reprogramming and related to poor prognosis in patients, IDH2 might become a new therapeutic target for restoring chemosensitivity in chemo-resistant urothelial carcinoma.

Vasohibin-1 Expression Can Predict Pathological Complete Remission of Advanced Bladder Cancer with Neoadjuvant Chemotherapy.

BACKGROUND AND PURPOSE: Neoadjuvant chemotherapy (NAC) is a well-established standard practice in invasive bladder cancer (BCa), however patient selection remains challenging. High expression of vasohibin-1 (VASH1), an endogenous regulator of angiogenesis, has been reported in high-grade and advanced BCa; however, its prognostic value for chemotherapy outcomes remains unexplored. In this study, we sought to identify biomarkers of chemotherapy response focusing on the relationship between angiogenesis and tissue hypoxia. METHODS: Forty Japanese patients with BCa who underwent NAC and radical cystectomy were included in the present analysis. We compared the immunohistochemical expression of CD34, VASH1, and carbonic anhydrase 9 (CA9) between patients who achieved tumor clearance at operation (ypT0) and those with residual disease after cystectomy. RESULTS: There were 19 patients in the ypT0 group, while the remaining 21 patients had residual tumors at operation. Patients in the ypT0 group had high microvessel density (p = 0.031), high VASH1 density (p < 0.001), and stronger CA9 staining (p = 0.046) than their counterparts. Multivariate analysis identified microvessel and VASH1 density as independent predictive factors for pathological ypT0 disease (p = 0.043 and 0.002, respectively). The 5-year recurrence-free survival rate was higher in the high VASH1 density group than in the low VASH1 density group (66.3% vs. 33.3%, p = 0.036). CONCLUSION: VASH1 density is a potential therapeutic biomarker for chemotherapy response in BCa.

Prediction of pathological up-staging after radical nephroureterectomy in patients with upper tract urothelial carcinoma.

PURPOSE: The diagnostic accuracy of computed tomography urography for upper tract urothelial carcinoma is high; however, difficulties are associated with precisely assessing the T stage. Preoperative tumor staging has an impact on treatment options for upper tract urothelial carcinoma. We herein attempted to identify preoperative factors that predict pathological tumor up-staging, which will facilitate the selection of treatment strategies. MATERIALS AND METHODS: We retrospectively identified 148 patients with upper tract urothelial carcinoma who underwent computed tomography urography preoperatively followed by radical nephroureterectomy without preoperative chemotherapy at our institution between 2000 and 2021. Preoperative factors associated with cT2 or lower to pT3 up-staging were examined using a multivariate logistic regression analysis. RESULTS: Ninety out of 148 patients were diagnosed with cT2 or lower, and 22 (24%) were up-staged to pT3. A multivariate analysis identified a positive voided urine cytology (HR 4.69, p = 0.023) and tumor length ≥ 3 cm (HR 6.33, p = 0.003) as independent predictors of pathological tumor up-staging. CONCLUSIONS: Patients diagnosed with cT2 or lower, but with preoperative positive voided urine cytology and/or tumor diameter ≥ 3 cm need to be considered for treatment as cT3.

Anemia in patients ≥ 75 years with metastatic clear cell renal cell carcinoma: an important poor prognostic factor in the international metastatic renal cell carcinoma database consortium model.

BACKGROUND: Due to an increase in life expectancy, the incidence of metastatic renal cell carcinoma (mRCC) in patients aged ≥75 years has been increasing. In this study we investigated the characteristics before treatment and the outcomes of systemic therapies for patients aged ≥75 years with mRCC and compared the results with those for patients aged < 75 years in order to determine whether differences in age influenced survival. METHODS: A total of 206 consecutive Japanese patients with mRCC, including 47 patients aged ≥75 years, who received systemic therapy were included. Clinical data from medical records were retrieved and analyzed retrospectively. Survival analyses were determined using a Kaplan-Meier method, and analyzed with a log-rank test. RESULTS: Elderly patients categorized as favorable risk group based on the International Metastatic RCC Database Consortium (IMDC) stratification system were significantly lower. Among IMDC risk factors, the rate of anemia was significantly higher in elderly patients. No statistically significant benefit in progression free survival for first and second line treatment was observed, whereas improvements in overall survival as well as cancer specific survival were seen in patients aged < 75 years. CONCLUSIONS: For mRCC patients aged ≥75 years, a higher proportion of base line anemia, which resulted in higher rates of IMDC intermediate/poor risk, would be responsible for shorter OS/CSS. Furthermore, mRCC patients aged ≥75 years tend to receive BSC instead of second line active treatment. Overcoming under-treatment in elderly patients might help to prolong survival in mRCC.

Risk factors for postoperative fever after laparoscopic adrenalectomy focusing on hormones produced: a case control study.

BACKGROUND: Laparoscopic adrenalectomy is widely performed for a number of hormone-producing tumors and postoperative management depends on the hormones produced. In the present study, we conducted a retrospective analysis to clarify the risk factors for postoperative complications, particularly postoperative fever after laparoscopic adrenalectomy. METHODS: We analyzed 406 patients who underwent laparoscopic adrenalectomy at our hospital between 2003 and 2019. Postoperative fever was defined as a fever of 38 °C or higher within 72 h after surgery. We investigated the risk factors for postoperative fever after laparoscopic adrenalectomy. RESULTS: There were 188 males (46%) and 218 females (54%) with a median age of 52 years. Among these patients, tumor pathologies included 188 primary aldosteronism (46%), 75 Cushing syndrome (18%), and 80 pheochromocytoma (20%). Postoperative fever developed in 124 of all patients (31%), 30% of those with primary aldosteronism, 53% of those with pheochromocytoma, and 8% of those with Cushing syndrome. A multivariate logistic regression analysis identified pheochromocytoma and non-Cushing syndrome as independent predictors of postoperative fever. Postoperative fever was observed in 42 out of 80 cases of pheochromocytoma (53%), which was significantly higher than in cases of non-pheochromocytoma (82/326, 25%, p < 0.01). In contrast, postoperative fever developed in 6 out of 75 cases of Cushing syndrome (8%), which was significantly lower than in cases of non-Cushing syndrome (118/331, 35.6%, p < 0.01). CONCLUSION: Since postoperative fever after laparoscopic adrenalectomy is markedly affected by the hormone produced by pheochromocytoma and Cushing syndrome, it is important to carefully consider the need for treatment.

Appropriate definition of non-metastatic castration-resistant prostate cancer (nmCRPC) and optimal timing of androgen receptor signaling inhibitor (ARSI).

BACKGROUND: Defined by rising PSA levels under androgen deprivation therapy (ADT) despite no visible metastases on conventional imaging, non-metastatic castration-resistant prostate cancer (nmCRPC) represents a complex clinical challenge. A significant subset of these patients rapidly develops metastatic disease, negatively impacting survival. We examined the difference in prognosis of nmCRPC patients according to the timing of therapeutic interventions with androgen receptor signaling inhibitor (ARSI). METHODS: We examined 102 nmCRPC patients treated with ARSI. We divided patients according to their PSA levels when ARSI was administered: Cohort A (PSA 0.5-2.0 ng/mL), Cohort B (PSA 2.0-4.0 ng/mL), and Cohort C (PSA > 4.0 ng/mL). Utilizing the Kaplan-Meier method for survival analysis, our analytical starting point was the moment when PSA levels exceeded 0.5 ng/mL post-ADT nadir, ensuring a fair comparison and minimizing lead-time bias. RESULTS: After excluding 5 patients whose PSA nadir after ADT > 0.5 ng/mL, patient distribution across Cohort A, Cohort B, and Cohort C was 32, 24, and 41 patients, respectively. Kaplan-Meier survival analysis highlighted a 2-year metastasis-free survival rate of 97% for Cohort A, 87% for Cohort B, and 73% for Cohort C. A marked statistical difference emerged when comparing Cohort A with Cohorts B and C, with a p-value of 0.043. CONCLUSION: The timely initiation of ARSI is paramount in nmCRPC management. Our findings strongly advocate for consideration of ARSI administration in nmCRPC patients before their PSA levels exceed 2.0 ng/mL. Our results indicated a PSA threshold of 1.0 ng/mL for nmCRPC definition which is more reasonable to administer ARSI without delay.

Current issues and management consensus of advanced prostate cancer: Report of the Advanced Prostate Cancer Consensus Conference-JAPAN 2023.

OBJECTIVE: To evaluate and compare the voting results of Japanese urologists with the global panel at the Advanced Prostate Cancer Consensus Conference (APCCC) 2022. METHODS: Among the 198 questions discussed at the APCCC 2022, the APCCC-JAPAN 2023 focused on 14 key questions related to the management of advanced prostate cancer with insufficient high-level evidence based on their relevance to the Japanese cohort. A panel of six prostate cancer experts addressed these 14 questions and presented the latest evidence to Japanese urologists who voted on-site using a web-based system. The results were compared with those of APCCC 2022. RESULTS: This study found significant differences in the voting results between Japanese urologists and the global panel regarding several crucial issues related to advanced prostate cancer management. These differences were those observed in treatment preferences, monitoring strategies, and treatment choices in specific clinical scenarios. These findings highlight the need for a nuanced approach tailored to the unique challenges with considerations of the Japanese healthcare environment. CONCLUSIONS: APCCC-JAPAN 2023 provides valuable insights into the current clinical issues surrounding the management of advanced prostate cancer in Japan. The partial divergence in the consensus between Japanese urologists and the global panel underscores the importance of a context-specific approach. The results of this study provide practical guidance for physicians facing complex challenges and should be used to inform decision-making in the management of advanced prostate cancer.

Prognostic role of the innate immune signature CD163 and "eat me" signal calreticulin in clear cell renal cell carcinoma.

The effects of the innate immune status on patients with clear cell renal cell carcinoma (ccRCC) currently remain unknown. We herein provided more extensive information about the inner landscape of immunobiology of ccRCC. In total, 260 ccRCC samples from three different cohorts consisting of 213 primary tumors and 47 metastases were obtained. We focused on five representative innate immune signatures, CD68, CD163, the "eat me" signal calreticulin, the "don't eat me" signal CD47, and signal regulatory protein α, and examined the role of each signature by quantitative immunohistochemistry. We then conducted an integrated genome mutation analysis by next-generation sequencing. Among the five markers, high CD163 and low calreticulin expression levels were prognostic in ccRCC. The application of a new risk model based on CD163 and calreticulin levels, named the innate immune risk group (high risk: high-CD163/low calreticulin, intermediate risk: high-CD163/high calreticulin or low CD163/low calreticulin, low risk: low-CD163/high calreticulin), enabled the sequential stratification of patient prognosis and malignancy. Although organ-specific differences were observed, metastases appeared to have a higher innate immune risk, particularly in the lungs, with 50% of ccRCC metastases being classified into the high-risk group according to our risk score. An analysis of genomic alterations based on the innate immune risk group revealed that alterations in the TP53/Cell cycle pathway were highly prevalent in high-risk ccRCC patients according to two innate immune signatures CD163 and calreticulin. The present results provide insights into the immune-genomic biology of ccRCC tumors for innate immunity and will contribute to future therapies focused on the innate immune system in solid cancers.

Clinical risk management of breast, ovarian, pancreatic, and prostatic cancers for BRCA1/2 variant carriers in Japan.

Opportunities for genetic counseling and germline BRCA1/2 (BRCA) testing are increasing in Japan owing to cancer genomic profiling testing and companion diagnostics being covered by national health insurance for patients with BRCA-related cancers. These tests are useful not only to judge whether platinum agents and PARP inhibitors are indicated but also to reveal an autosomal-dominant inherited cancer syndrome: hereditary breast and ovarian cancer. In individuals with germline BRCA variants, risk of cancers of the breast, ovary, pancreas, and prostate is significantly increased at various ages of onset, but the stomach, uterus, biliary tract, and skin might also be at risk. For women with pathogenic BRCA variants, breast awareness and image analyses should be initiated in their 20s, and risk-reducing procedures such as mastectomy are recommended starting in their 30s, with salpingo-oophorectomy in their late 30s. For male BRCA pathogenic variant carriers, prostatic surveillance should be applied using serum prostate-specific antigen starting in their 40s. For both sexes, image examinations ideally using endoscopic ultrasound and magnetic resonance cholangiopancreatography and blood testing should begin in their 50s for pancreatic surveillance. Homologous recombination pathway-associated genes are also causative candidates. Variant pathogenicity needs to be evaluated every 6-12 months when results are uncertain for clinical significance. Genetic counseling needs to be offered to the blood relatives of the pathogenic variant carriers with suitable timing. We review the recommended cross-organ BRCA risk management in Japan.

Long-Term Prognosis and Treatment Strategy of Persistent PSA After Radical Prostatectomy.

PURPOSE: Prostate-specific antigen (PSA) is thought to be undetectable (< 0.1 ng/mL) after radical prostatectomy (RP), and persistent PSA (≥ 0.1 ng/mL) is considered a failure of curative treatment. MATERIALS AND METHODS: The study population consisted of 135 patients, all of whom underwent RP for localized prostate cancer, and developed persistent PSA. We set the starting point at the timing of RP, and the endpoints were the development of castration-resistant prostate cancer (CRPC) and cancer-specific survival. RESULTS: Salvage radiation therapy (RT) and androgen deprivation therapy (ADT) were performed in 53 (39.3%) and 64 (47.4%) patients, respectively. Eighteen (13.3%) patients didn't receive any salvage treatment. During the median follow-up of 10.1 years, CRPC was observed in 23 patients, and 6 patients died due to prostate cancer. Kaplan-Meier curves demonstrated the 15-year CRPC-free and cancer-specific survivals were 79.5% and 92.7%, respectively. Cox multivariate analysis demonstrated that seminal vesicle invasion (SVI) (p = 0.007) and nadir PSA ≥1.0 ng/mL (p = 0.002) were independent risk factors for CRPC. Salvage RT demonstrated better cancer control (the 10-and 15-year CRPC-free survival was 94.1% and 94.1%) compared to ADT (75.9% and 58.5%, p = 0.017) after 1:1 propensity score matching. CONCLUSIONS: SVI and nadir PSA ≥1.0 ng/mL are independent risk factors for CRPC in patients with persistent PSA after RP. Salvage RT is considered to be the optimal treatment for this condition.

The sialyl-Tn antigen synthase genes regulates migration-proliferation dichotomy in prostate cancer cells under hypoxia.

A low-oxygen (hypoxia) tumor microenvironment can facilitate chemotherapy and radiation therapy resistance in tumors and is associated with a poor prognosis. Hypoxia also affects PCa (prostate cancer) phenotype transformation and causes therapeutic resistance. Although O-glycans are known to be involved in the malignancy of various cancers under hypoxia, the expression and function of O-glycans in PCa are not well understood. In this study, the saccharide primer method was employed to analyze O-glycan expression in PCa cells. Results showed that the expression of sTn antigens was increased in PCa cells under hypoxia. Furthermore, it was found that ST6GalNAc1, the sTn antigen synthase gene, was involved in the migration-proliferation dichotomy and drug resistance in PCa cells under hypoxia. The results of this study will contribute to the development of novel diagnostic markers and drug targets for PCa under hypoxia.

Factors affecting the selection of eligible candidates for focal therapy for prostate cancer.

PURPOSE: Focal therapy (FT) is a treatment modality for prostate cancer that aims to reduce side effects. However, it remains difficult to select eligible candidates. We herein examined eligibility factors for hemi-ablative FT for prostate cancer. METHODS: We identified 412 patients who were diagnosed with unilateral prostate cancer by biopsy and had undergone radical prostatectomy between 2009 and 2018. Among these patients, 111 underwent MRI before biopsy, had 10-20 core biopsies performed, and did not receive other treatments before surgery. Fifty-seven patients with prostate-specific antigen ≥ 15 ng/mL and biopsy Gleason score (GS) ≥ 4 + 3 were excluded. The remaining 54 patients were evaluated. Both lobes of the prostate were scored using Prostate Imaging Reporting and Data System version 2 on MRI. Ineligible patients for FT were defined as those with ≥ 0.5 mL GS6 or GS ≥ 3 + 4 in the biopsy-negative lobe, ≥ pT3, or lymph node involvement. Selected predictors of eligibility for hemi-ablative FT were analyzed. RESULTS: Among our cohort of 54 patients, 29 (53.7%) were eligible for hemi-ablative FT. A multivariate analysis identified a PI-RADS score < 3 in the biopsy-negative lobe (p = 0.016) as an independent predictor of eligibility for FT. Thirteen out of 25 ineligible patients had GS ≥ 3 + 4 tumors in the biopsy-negative lobe, half of whom (6/13) also had a PI-RADS score < 3 in the biopsy-negative lobe. CONCLUSION: The PI-RADS score in the biopsy-negative lobe may be important in the selection of eligible candidates for FT. The findings of this study will help reduce missed significant prostate cancers and improve FT outcomes.

Prognostic significance of p16, p21, and Ki67 expression at the invasive front of colorectal cancers.

Cancer cells at the invasive front are believed to be responsible for invasion/metastasis. This has led to examining various morphological features and protein expressions at the invasive front. However, accurate assessment of the pathological section requires long-time training, and inter-observer disagreement is problematic. Immunohistochemistry and digital imaging analysis may mitigate these problems; however, the choice of which proteins to stain and the best analysis method remains controversial. We used the "go-or-grow" hypothesis to select markers with the greatest prognostic relevance. Importantly, nonproliferating cells can migrate. We used Ki67 as a proliferation marker, with p16 and p21 designating nonproliferating cells. We established a semi-automated quantification workflow to study protein expression in serial pathological sections. A total of 51 patients with completely resected colorectal cancer (stages I-IV) were analyzed, and 44 patients were followed up. Patients with cancer cells with p16-high/p21-low or p21-low/Ki67-low at the deepest invasive front demonstrated a significantly worse prognosis than those who did not display these characteristics. These results suggest that the nonproliferating cancer cells at the invasion front possess invasion/metastatic property with heterogeneity of senescence.

Strategy for PSA progression in patients undergoing salvage radiation for biochemical recurrence after radical prostatectomy.

BACKGROUND: The treatment strategy for prostate-specific antigen (PSA) progression in patients who receive salvage radiation therapy (RT) for biochemical recurrence (BCR) after radical prostatectomy (RP) is salvage androgen deprivation therapy (ADT). However, its optimal timing is highly controversial. METHODS: The study sample consisted of 77 men who underwent RP, received salvage RT against BCR, and underwent salvage ADT for PSA progression. The endpoint of this study was development to castration-resistant prostate cancer (CRPC), from the start of salvage RT. RESULTS: The median follow-up time was 9.5 years, and 20 patients experienced CRPC. The multivariable analysis identified PSA-doubling time (PSA-DT) ≤ 12 months (hazard ratio, 3.5) and seminal vesicle invasion (SVI) (hazard ratio, 4.4) as independent risk factors. We defined the high-risk and low-risk groups as those with one or two risk factors and no risk factors, respectively. In the high-risk group, a significant difference in time to CRPC was observed between patients who received salvage ADT at PSA ≤ 1.0 ng/mL (n = 8) and at > 1.0 ng/mL (n = 27) (10-year non-CRPC rate: 100.0% vs. 46.3%, respectively). In contrast, in the low-risk group, no significant difference in CRPC-free survival was observed between patients who received salvage ADT at PSA ≤ 1.0 ng/mL (n = 14) and at > 1.0 ng/mL (n = 28) (10-year non-CRPC rate: 86.4% vs. 80.8%, respectively). CONCLUSION: In high-risk patients (PSA-DT ≤ 12 months and/or SVI), salvage ADT for PSA progression after salvage RT should be started before the PSA levels exceed 1.0 ng/mL.

Androgen deprivation therapy duration is significantly associated with Testosterone recovery in Japanese patients with prostate cancer.

OBJECTIVE: Due to the fear generated by COVID-19 in Spring 2020, many patients postponed their scheduled outpatient visits. To differentiate those patients with prostate cancer (PCa) whose androgen deprivation therapy (ADT) injection treatment can be postponed, we investigated the characteristics of testosterone (T) recovery in Japanese patients after they received combined ADT and radiation therapy (RT). METHODS: We included 81 patients with PCa treated with ADT and RT at Keio University Hospital from January 2013 to December 2018. T-recovery was defined as the time interval between the last ADT injection and 3-6 months after T-normalization. The Kaplan-Meier method was used to estimate time to T-recovery. Cox proportional hazards models identified T-recovery predictors. RESULTS: The 50% cumulative incidence of T-recovery was 7.0 months for the 6-short-term group (defined as patients having ≤6 months of ADT therapy) versus 13.0 months for the 6-long-term group (>6 months of therapy) (p < 0.001). The incidence was 7.0 months for the 12 short-term-ADT (ST) group versus 18.0 months for the 12 long-term-ADT (LT) group (p < 0.001). Multivariate analysis revealed that a shorter duration of ADT was associated with a shorter time to T-recovery (hazard ratio, 0.253; 95% CI, 0.138-0.465; p < 0.001). No other factors were significant predictors of T-recovery. CONCLUSION: Androgen deprivation therapy duration is significantly associated with T-recovery in Japanese patients with PCa. If a patient undergoes ADT for more than 6 or 12 months, it is possible to postpone their outpatient visits for 13 and 18 months, respectively.

Predictors of urinary function recovery after laparoscopic and robot-assisted radical prostatectomy.

INTRODUCTION: Even in the era of laparoscopic radical prostatectomy (LRP) and robot-assisted laparoscopic radical prostatectomy (RALP), we sometimes encounter patients with severe urinary incontinence after surgery. The aim of the present study was to identify predictors of urinary continence recovery among patients with urinary incontinence immediately after surgery (UIIAS). MATERIALS AND METHODS: We identified 274 patients with clinically localized prostate cancer who underwent LRP and RALP between 2011 and 2018. UIIAS was defined as a urine loss ratio > 0.15 on the first day of urethral catheter removal. Urinary continence recovery was defined as using ≤ 1 pad/day one year after surgery. In the present study, we evaluated factors affecting urinary function recovery one year after surgery among patients with urinary incontinence immediately after LRP and RALP. RESULTS: UIIAS was observed in 191 out of 274 patients (69.7%). A multivariate analysis identified age (<65 years, p = 0.015) as an independent predictor affecting immediate urinary continence. Among 191 incontinent patients, urinary continence one year after surgery improved in 153 (80.1%). A multivariate analysis identified age (<65 years, p = 0.003) and estimated blood loss (≥ 100 mL, p = 0.044) as independent predictors affecting urinary continence recovery one year after surgery. CONCLUSION: The present results suggest that younger patients and patients with higher intraoperative blood loss recover urinary continence one year after surgery even if they are incontinent immediately after surgery.

Nuclear Ceramide Is Associated with Ataxia Telangiectasia Mutated Activation in the Neocarzinostatin-Induced Apoptosis of Lymphoblastoid Cells.

Ceramide is a bioactive sphingolipid that mediates ionizing radiation- and chemotherapy-induced apoptosis. Neocarzinostatin (NCS) is a genotoxic anti-cancer drug that induces apoptosis in response to DNA double-strand breaks (DSBs) through ataxia telangiectasia mutated (ATM) activation. However, the involvement of ceramide in NCS-evoked nuclear events such as DSB-activated ATM has not been clarified. Here, we found that nuclear ceramide increased by NCS-mediated apoptosis through the enhanced assembly of ATM and the meiotic recombination 11/double-strand break repair/Nijmengen breakage syndrome 1 (MRN) complex proteins in human lymphoblastoid L-39 cells. NCS induced an increase of ceramide production through activation of neutral sphingomyelinase (nSMase) and suppression of sphingomyelin synthase (SMS) upstream of DSB-mediated ATM activation. In ATM-deficient lymphoblastoid AT-59 cells compared with L-39 cells, NCS treatment showed a decrease of apoptosis even though ceramide increase and DSBs were observed. Expression of wild-type ATM, but not the kinase-dead mutant ATM, in AT-59 cells increased NCS-induced apoptosis despite similar ceramide accumulation. Interestingly, NCS increased ceramide content in the nucleus through nSMase activation and SMS suppression and promoted colocalization of ceramide with phosphorylated ATM and foci of MRN complex. Inhibition of ceramide generation by the overexpression of SMS suppressed NCS-induced apoptosis through the inhibition of ATM activation and assembly of the MRN complex. In addition, inhibition of ceramide increased by the nSMase inhibitor GW4869 prevented NCS-mediated activation of the ATM. Therefore, our findings suggest the involvement of the nuclear ceramide with ATM activation in NCS-mediated apoptosis. SIGNIFICANCE STATEMENT: This study demonstrates that regulation of ceramide with neutral sphingomyelinase and sphingomyelin synthase in the nucleus in double-strand break-mimetic agent neocarzinostatin (NCS)-induced apoptosis. This study also showed that ceramide increase in the nucleus plays a role in NCS-induced apoptosis through activation of the ataxia telangiectasia mutated/meiotic recombination 11/double-strand break repair/Nijmengen breakage syndrome 1 complex in human lymphoblastoid cells.

Functional analysis of GCNT3 for cell migration and EMT of castration-resistant prostate cancer cells.

Castration-resistant prostate cancer (CRPC) is a malignant tumor that is resistant to androgen deprivation therapy. Treatments for CRPC are limited, and no diagnostic markers are currently available. O-glycans are known to play an important role in cell proliferation, migration, invasion, and metastasis of cancer cells. However, the differences in the O-glycan expression profiles for normal prostate cancer (PCa) cells compared with CRPC cells have not yet been investigated. In this study, the saccharide primer method was employed to analyze the O-glycans expressed in CRPC cells. Expression levels of core 4-type O-glycans were significantly increased in CRPC cells. Furthermore, the expression level of N-Acetylglucosaminyltransferase 3 (GCNT3), a core 4-type O-glycan synthase gene, was increased in CRPC cells. The expression of core 4-type O-glycans and GCNT3 was presumed to be regulated by androgen deprivation. GCNT3 knockdown induced cell migration and epithelial-mesenchymal transition. These observations elucidate the mechanism of acquisition of castration resistance in PCa and offer new possibilities for the development of diagnostic markers and therapeutic targets in the treatment of PCa.

Influence of response to prior docetaxel on sensitivity to cabazitaxel in prostate cancer patients with PTEN alterations.

The purpose of this study was to investigate factors predicting the sensitivity to cabazitaxel therapy in metastatic castration-resistant prostate cancer (mCRPC) patients with phosphatase and tensin homolog deleted from chromosome 10 (PTEN) alterations. This single-institution, retrospective study included 12 mCRPC patients with PTEN alterations who had received cabazitaxel therapy. Five patients (41%) responded to cabazitaxel therapy with a prostate-specific antigen (PSA) level decline of ≥30% from baseline, and all of them had responded to prior docetaxel therapy with a PSA decline of ≥30%. None of the patients with a poor response to prior docetaxel therapy responded well to cabazitaxel therapy. Of the seven patients who did not respond to cabazitaxel and whose PSA declined from baseline was <30%, five (71%) were also refractory to prior docetaxel therapy. The PSA responses to docetaxel and cabazitaxel were significantly correlated (p = 0.027). Kaplan-Meier analysis revealed that progression-free survival (PFS) for cabazitaxel was significantly shorter for prior docetaxel nonresponders (3.3 versus 9.1 months, p = 0.028). Multivariate analysis revealed that a poor response to prior docetaxel (PSA decline < 30%) (hazard ratio [HR] = 6.382, 95% confidence interval [CI] 1.172-34.750, p = 0.032) and baseline PSA of ≥20 ng/ml (HR = 33.584, 95% CI 2.332-483.671, p = 0.010) were independent prognostic factors for PFS with cabazitaxel therapy. These results demonstrate cross-resistance between docetaxel and cabazitaxel. The response to prior docetaxel therapy can influence the sensitivity to cabazitaxel therapy in mCRPC patients with PTEN alterations.

Hybridisation chain reaction-based visualisation and screening for lncRNA profiles in clear-cell renal-cell carcinoma.

BACKGROUND: Analysis of long noncoding RNA (lncRNA) localisation at both the tissue and subcellular levels can provide important insights into the cell types that are important for their function. METHODS: By applying new fluorescent in situ hybridisation technique called hybridisation chain reaction (HCR), we achieved a high-throughput lncRNA visualisation and evaluation of clinical samples. RESULTS: Assessing 1728 pairs of 16 lncRNAs and clear-cell renal-cell carcinoma (ccRCC) specimens, three lncRNAs (TUG1, HOTAIR and CDKN2B-AS1) were associated with ccRCC prognosis. Furthermore, we derived a new lncRNA risk group of ccRCC prognosis by combining the expression levels of these three lncRNAs. Examining genomic alterations underlying this classification revealed prominent features of tumours that could serve as potential biomarkers for targeting lncRNAs. We then derived combination of HCR with expansion microscopy and visualised nanoscale-resolution HCR signals in cell nuclei, uncovering intracellular colocalization of three lncRNA (TUG1, HOTAIR and CDKN2B-AS1) signals such as those located intra- or out of the nucleus or nucleolus in cancer cells. CONCLUSION: LncRNAs are expected to be desirable noncoding targets for cancer diagnosis or treatments. HCR involves plural probes consisting of small DNA oligonucleotides, clinically enabling us to detect cancerous lncRNA signals simply and rapidly at a lower cost.