SLFN11 Blocks Stressed Replication Forks Independently of ATR.

SLFN11 sensitizes cancer cells to a broad range of DNA-targeted therapies. Here we show that, in response to replication stress induced by camptothecin, SLFN11 tightly binds chromatin at stressed replication foci via RPA1 together with the replication helicase subunit MCM3. Unlike ATR, SLFN11 neither interferes with the loading of CDC45 and PCNA nor inhibits the initiation of DNA replication but selectively blocks fork progression while inducing chromatin opening across replication initiation sites. The ATPase domain of SLFN11 is required for chromatin opening, replication block, and cell death but not for the tight binding of SLFN11 to chromatin. Replication stress by the CHK1 inhibitor Prexasertib also recruits SLFN11 to nascent replicating DNA together with CDC45 and PCNA. We conclude that SLFN11 is recruited to stressed replication forks carrying extended RPA filaments where it blocks replication by changing chromatin structure across replication sites.

Newly developed preclinical models reveal broad-spectrum CDK inhibitors as potent drugs for CRPC exhibiting primary resistance to enzalutamide.

Androgen-deprivation therapy is a standard treatment for advanced prostate cancer. However, most patients eventually acquire resistance and progress to castration-resistant prostate cancer (CRPC). In this study, we established new CRPC cell lines, AILNCaP14 and AILNCaP15, from LNCaP cells under androgen-deprived conditions. Unlike most pre-existing CRPC cell lines, both cell lines expressed higher levels of androgen receptor (AR) and prostate-specific antigen (PSA) than parental LNCaP cells. Moreover, these cells exhibited primary resistance to enzalutamide. Since AR signaling plays a significant role in the development of CRPC, PSA promoter sequences fused with GFP were introduced into AILNCaP14 cells to conduct GFP fluorescence-based chemical screening. We identified flavopiridol, a broad-spectrum CDK inhibitor, as a candidate drug that could repress AR transactivation of CRPC cells, presumably through the inhibition of phosphorylation of AR on the serine 81 residue (pARSer81 ). Importantly, this broad-spectrum CDK inhibitor inhibited the proliferation of AILNCaP14 cells both in vitro and in vivo. Moreover, a newly developed liver metastatic model using AILNCaP15 cells revealed that the compound attenuated tumor growth of CRPC harboring highly metastatic properties. Finally, we developed a patient-derived xenograft (PDX) model of CRPC and DCaP CR from a patient presenting therapeutic resistance to enzalutamide, abiraterone, and docetaxel. Flavopiridol successfully suppressed the tumor growth of CRPC in this PDX model. Since ARSer81 was found to be phosphorylated in clinical CRPC samples, our data suggested that broad-spectrum CDK inhibitors might be a potent candidate drug for the treatment of CRPC, including those exhibiting primary resistance to enzalutamide.

The efficacy of second-line tyrosine kinase inhibitor for patients with metastatic non-clear cell renal cell carcinoma following first-line immune-oncology combination therapy.

PURPOSE: Metastatic non-clear cell renal cell carcinoma (nccRCC) is a heterogeneous disease with a poor prognosis and is treated with immunotherapy (IO)-based combinations according to the clear cell renal cell carcinoma. Tyrosine-kinase inhibitors (TKIs), such as cabozantinib and axitinib, are commonly used as the 2nd line therapy after 1st line IO combination therapy, but their efficacy as 2nd line TKI therapy for nccRCC is unknown. In this study, we performed a retrospective multicenter analysis of nccRCC patients who were previously treated with IO combination therapy and received 2nd line TKIs. METHODS: Among 254 patients enrolled in the Japanese multicenter retrospective study, 52 patients with nccRCC histology who received second-line TKIs were included in this study. Progression-free survival and overall survival (OS) from 2nd line TKIs were analyzed by log-rank test and Cox-proportional hazard model. Objective response rate (ORR) of 2nd line TKIs were analyzed. RESULTS: The 1-year PFS and OS rates were 25.0% (95% CI = 13.1-36.8) and 63.8% (95% CI, 48.0-75.9), respectively. No patients had a complete response, 11 had a partial response, and 18 had stable disease. ORR was 21.1%. IMDC poor risk and sunitinib as the 2nd line therapy were significantly associated with poor PFS. CONCLUSION: The 2nd-line TKI was effective for a small group of nccRCC patients previously treated with IO combination therapy, although this study was retrospectively analyzed with a small number of cases.

Clinical characteristics and survival outcomes of elderly patients with de novo metastatic germ cell tumors.

OBJECTIVES: To determine the outcomes for elderly patients with de novo metastatic germ cell tumors and the influence of patient age on adherence to standard chemotherapy. METHODS: A total of 150 patients who were initially diagnosed with metastatic germ cell tumors and treated at our institution between 2007 and 2021 were included. Patients were classified according to three age groups: aged <40, 40-49, and ≥50 years. Clinicopathological features, adherence to standard first-line chemotherapy, overall survival, and disease-free survival were compared between these groups. We also analyzed the outcomes of patients who received low-intensity induction chemotherapy due to adverse events and/or comorbidities. RESULTS: There was no significant difference in any of the survival outcomes and in the rate of adherence to standard first-line chemotherapy between the three age groups, although elderly patients with intermediate/poor prognosis group tended to receive less-intense chemotherapies. The rate of febrile neutropenia as a chemotherapy-related adverse event was significantly higher in patients aged ≥50 years. No statistical significance in survival outcomes was detected between the group of patients who received relatively low-intensity induction chemotherapy and those who received adequately intensive planned chemotherapy. CONCLUSIONS: The adherence rate of standard fist-line chemotherapy of elderly patients is almost comparable to that of younger patients, although some adverse events should be carefully managed. Even elderly patients with metastatic germ cell tumors can aim for equivalently good survival outcome like younger populations, with effort to adhere to standard chemotherapy.

Development of drugs targeting hypoxia-inducible factor against tumor cells with VHL mutation: Story of 127 years.

Intratumoral hypoxia is associated with tumor progression and therapeutic resistance. The VHL tumor suppressor gene was identified in 1993, and later studies revealed that the gene product pVHL interacts with other proteins to form the VBC complex. The VBC complex functions as an E3 ubiquitin ligase and regulates the abundance of the α-subunit of the transcription factor hypoxia-inducible factor (HIF). Hypoxia-inducible factor regulates thousands of genes required for cells to adapt and survive in hypoxic conditions, and thus pVHL plays a major role in oxygen-sensing pathways. Patients with von Hippel-Lindau (VHL) disease, harboring a germline mutation of the VHL gene, develop renal cell carcinomas and a series of tumors showing hypervascular phenotypes. The extensive findings that have clarified the function of VHL have contributed to the development of novel first-in-human drugs, including belzutifan, a HIF-2α inhibitor. The 2019 Nobel Prize in Physiology or Medicine was awarded to Dr. William G. Kaelin Jr., Dr. Peter J. Ratcliffe, and Dr. Gregg L. Semenza as researchers contributing to clarifying the mechanism of the oxygen-sensing pathway of cells. The first report of VHL disease was in 1894, meaning the development of a specific drug for this disease took almost 125 years. In this article, we describe how researchers and clinician scientists successfully clarified the function of VHL and achieved a preclinical proof of concept to apply for clinical trials, key requirements for drug development.

Novel Manifestation of Retinal Hemangioblastomas Detected by OCT Angiography in von Hippel-Lindau Disease.

PURPOSE: To elucidate the clinical characteristics of atypical retinal vascular proliferation in patients with von Hippel-Lindau (VHL) disease using OCT angiography (OCTA). DESIGN: Prospective, observational study. PARTICIPANTS: Fifty-seven consecutive patients with a diagnosis of VHL disease who visited Kyoto University Hospital between January 2019 and March 2022. METHODS: Retinal hemangioblastomas (RHs) were assessed using multimodal imaging including OCTA. Retinal hemangioblastomas were classified into 2 phenotypes: nodular and flat. Nodular RHs were defined as typical RHs that were globular, well-circumscribed tumors, often accompanied with dilated feeder arterioles and draining venules. Flat RHs lacked a protruded red or colored mass, had variable and indistinct borders, and were not accompanied with feeder and draining vessels. MAIN OUTCOME MEASURES: The prevalence, distribution, and description of atypical flat RHs. RESULTS: Among 57 consecutive patients with VHL disease, 37 patients (64.9%) showed RHs in at least 1 eye. Bilateral RHs were seen in 23 patients (62.2%). Among 58 eyes of 37 patients with RHs, typical nodular RHs were detected in 54 eyes. Nodular RHs were seen mainly in the peripheral retina and occasionally in the peripapillary region, and they showed exudative changes in some cases. Flat RHs were detected in 7 eyes (12.1%). Four eyes showed only flat RHs, and 3 eyes showed both types in the same eye. Most flat RHs appeared as retinal hemorrhages or faint flat abnormal retinal vessels in the inner retina on the fundus examination, often within the macula area or peripapillary. In all eyes with flat RHs, OCTA showed abundant blood flow in the lesions. OCT revealed that flat RHs were seen mainly between the retinal nerve fiber layer and the ganglion cell layer, and occasionally within the inner nuclear layer. During a mean follow-up period of 20.4 ± 15.0 months, no flat RHs accompanied exudative change, tractional retinal detachment, or progression in size. CONCLUSIONS: Patients with VHL disease can demonstrate 2 distinct types of RHs: the classic nodular type and an atypical flat type. OCT angiography can be useful in improving the detection of atypical flat RHs, which can be difficult to detect clinically. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Comparison of therapeutic features and oncologic outcome in patients with pN1 prostate cancer among robot-assisted, laparoscopic, or open radical prostatectomy.

OBJECTIVES: To compare the therapeutic features and oncological outcomes of robot-assisted radical prostatectomy (RARP) with those of open radical prostatectomy (ORP) or laparoscopic radical prostatectomy (LRP) in lymph node (LN) positive prostate cancer patients in a retrospective observational multi-institutional study. PATIENTS AND METHODS: We evaluated the clinical results of 561 patients across 33 institutions who underwent RARP, LRP, or ORP and who were diagnosed with LN-positive prostate cancer during RP with pelvic LN dissection (PLND). We determined the following survival outcomes: metastasis-free survival, overall survival, cancer-specific survival, and biochemical recurrence-free survival. The Kaplan-Meier method, log-rank test, and Cox proportional hazards regression model were used to evaluate the effect of treatment on oncological outcomes. Statistical significance was set at P < 0.05. RESULTS: There was no significant difference for any of the survival outcomes between the three surgical groups. However, RARP achieved a greater LN yield compared to that of ORP or LRP. When the extent of PLND was limited to the obturator LNs, the number of removed LNs (RLNs) was comparable between the three surgical groups. However, higher numbers of RLNs were achieved with RARP compared to the number of RLNs with ORP (P < 0.001) when PLND was extended to the external and/or internal iliac LNs. CONCLUSION: RARP, LRP, and ORP provided equal surgical outcomes for pN1 prostate cancer, and the prognosis was relatively good for all procedures. Increased numbers of RLNs may not necessarily affect the oncological outcome.

Circulating microRNA profiling for prediction of oncological outcomes in prostate cancer patients following radical prostatectomy.

BACKGROUND: Although radical prostatectomy is associated with good long-term oncological outcomes, approximately 30% of patients present biochemical recurrence, whereupon salvage treatments are required. Identification of novel molecular biomarkers to predict cancer behavior is clinically important. Here, we developed a novel microRNA (miRNA)-based prognostic model for patients who underwent radical prostatectomy. METHODS: We retrospectively investigated the clinical records of 295 patients who underwent radical prostatectomy between 2009 and 2017. We randomly assigned these cases into training or validation sets. The prognostic model was constructed using Fisher linear discriminant analysis in the training set, and we evaluated its performance in the validation set. RESULTS: Overall, 72 patients had biochemical recurrence. A prediction model was constructed using a combination of three miRNAs (miR-3147, miR-4513, and miR-4728-5p) and two pathological factors (pathological T stage and Gleason score). In the validation set, the predictive performance of the model was confirmed to be accurate (area under the receiver operating characteristic curve: 0.80; sensitivity: 0.78; specificity: 0.76). Additionally, Kaplan-Meier analysis revealed that the patients with a low prediction index had significantly longer recurrence-free survival than those with a high index (p < 0.001). CONCLUSIONS: Circulating miRNA profiles can provide information to predict recurrence after prostatectomy. Our model may be helpful for physicians to decide follow-up strategies for patients.

The clinical significance of perioperative inflammatory index as a prognostic factor for patients with retroperitoneal soft tissue sarcoma.

BACKGROUND: The prognostic factors of retroperitoneal soft tissue sarcoma (STS) have been explored but not yet certain. This study evaluated the prognostic impact of various preoperative clinical parameters and inflammatory indices in primary STS, with a particular focus on the transition of inflammatory index before and after tumor resection in de-differentiated liposarcoma (DD-LPS). METHODS: The clinical data of 113 patients with primary retroperitoneal STS receiving tumor resection were reviewed. Six variables (neutrophils, platelets, C-reactive protein (CRP), lymphocytes, albumin, and hemoglobin) in the blood samples were measured and nine inflammatory indices (neutrophil-lymphocyte ratio (NLR), CRP-lymphocyte ratio (CLR), platelet-lymphocyte ratio (PLR), neutrophil-albumin ratio (NAR), CRP-albumin ratio (CAR), platelet-albumin ratio (PAR), HALP (hemoglobin, albumin, lymphocyte and platelet), prognostic nutrition index (PNI), and modified Glasgow Prognostic Score (mGPS)) were calculated. The prognostic value of the indices was analyzed by univariate and multivariate analyses. RESULTS: Elevated NLR, CLR, PLR, NAR, CAR, PAR, and mGPS were associated with a worse overall survival (p = 0.0124, 0.0011, 0.049, 0.0047, 0.0085, 0.0332, and 0.0086, respectively) in univariate analysis. Multivariate analysis showed that elevated CLR and DD-LPS were associated with poor overall survival (p = 0.0267 and 0.0218, respectively) in all retroperitoneal STS. In DD-LPD, patients with preoperative high CLR, whose postoperative CLR was normalized, demonstrated a favorable survival rate similar to those with preoperative low CLR. CONCLUSIONS: Elevated CLR before surgery as well as DD-LPS were poor prognostic markers for overall survival in primary retroperitoneal STS. Perioperative CLR normalization may be related to a favorable prognosis in DD-LPS.

Serum microRNA as liquid biopsy biomarker for the prediction of oncological outcomes in patients with bladder cancer.

OBJECTIVES: Radical cystectomy is the gold-standard treatment for muscle-invasive bladder cancer and aggressive non-muscle-invasive bladder cancer. To enhance clinical decision-making regarding patients with bladder cancer who underwent radical cystectomy, a recurrence prediction biomarker with high accuracy is urgently needed. In this study, we developed a model for the prediction of bladder cancer recurrence after radical cystectomy by combining serum microRNA and a pathological factor. METHODS: We retrospectively analyzed the clinical records of 81 patients with bladder cancer who underwent radical cystectomy between 2008 and 2016. The dataset was divided into two, and Fisher linear discriminant analysis was used to construct a prognostic model for future recurrence in the training set (n = 41). The performance of the model was evaluated in the validation set (n = 40). RESULTS: Thirty patients had recurrence after having undergone radical cystectomy. A prognostic model for recurrence was constructed by combining a pathological factor (i.e. positive pathological lymph node status) and three microRNAs (miR-23a-3p, miR-3679-3p, and miR-3195). The model showed a sensitivity of 0.87, a specificity of 0.80, and an area under the receiver operating characteristic curve of 0.88 (0.77-0.98) in the validation set. Furthermore, Kaplan-Meier analysis revealed that patients with a low prediction index have significantly longer overall survival than patients with a high prediction index (P = 0.041). CONCLUSION: A combination of serum microRNA profiles and lymph node statuses is useful for the prediction of oncological outcomes after radical cystectomy in patients with bladder cancer.