No abstract

TAR DNA-binding protein 43 (TDP-43) plays a key role in the neurodegenerative diseases including amyotrophic lateral sclerosis and frontotemporal lobar degeneration. The nature of the TDP-43-mediated neurotoxicity associated with these diseases is not yet understood. Here, we have established transgenic Caenorhabditis elegans models that express human TDP-43 variants in the nervous system, including the full-length wild-type (WT) and mutant proteins and a pathologic C-terminal fragment. The C. elegans models developed severe locomotor defects associated with the aggregation of TDP-43 in neurons. In comparison to parallel Cu/Zn superoxide dismutase worm models, transgenic full-length TDP-43, including the WT protein, was highly neurotoxic. In addition, TDP-43 demonstrated an unusually high tendency to aggregate, a property intrinsic to the WT protein. The C-terminal 25 kDa fragment of TDP-43 was unstable but remarkably aggregation-prone. Distinct disulfide-linked TDP-43 dimers and oligomers were detected. In C. elegans, the neurotoxicity and the protein aggregation of TDP-43 were regulated by environmental temperature and heat shock transcriptional factor 1, indicating that a deficiency in protein quality control is a risk factor for TDP-43 proteinopathy. Furthermore, the neurotoxicity and the protein aggregation of TDP-43 can be significantly attenuated by a deficiency in the insulin/insulin-like growth factor 1 (IGF-1) signaling in C. elegans and mammalian cells. These results suggest that protein misfolding underlies the aging-dependent neurodegeneration associated with TDP-43 and that the insulin/IGF-1 signaling may be a target for therapies.

Based on the present prospective single-centre experience, PHI density could be used to avoid 38% of unnecessary biopsies, while failing to detect only 2% of clinically significant cancers.

BACKGROUNDThe Prostate Health Index (phi) outperforms PSA and other PSA derivatives for the diagnosis of prostate cancer (PCa). The impact of phi testing in the real-world clinical setting has not been previously assessed.METHODSIn a single, large, academic center, phi was tested in 345 patients presenting for diagnostic evaluation for PCa. Findings on prostate biopsy (including Grade Group [GG], defined as GG1: Gleason score [GS] 6, GG2: GS 3+4=7, GG3: GS 4+3=7, GG4: GS 8, and GG5: GS 9-10), magnetic resonance imaging (MRI), and radical prostatectomy (RP) were prospectively recorded. Biopsy rates and outcomes were compared to a contemporary cohort that did not undergo phi testing (n=1318).RESULTSOverall, 39% of men with phi testing underwent prostate biopsy. No men with phi<19.6 were diagnosed with PCa, and only 3 men with phi<27 had cancer of GG≥2. Phi was superior to PSA for the prediction of any PCa (AUC 0.72 vs. 0.47) and GG≥2 PCa (AUC 0.77 vs. 0.53) on prostate biopsy. Among men undergoing MRI and phi, no men with phi<27 and PI-RADS≤3 had GG≥2 cancer. For those men proceeding to RP, increasing phi was associated with higher pathologic GG (p=0.002) and stage (p=0.001). Compared to patients who did not undergo phi testing, the use of phi was associated with a 9% reduction in the rate of prostate biopsy (39% vs. 48%; p<0.001). Importantly, the reduction in biopsy among the phi population was secondary to decreased incidence of negative (8%) and GG1 (1%) biopsies, while the proportion of biopsies detecting GG≥2 cancers remained unchanged.CONCLUSIONSIn this large, real-time clinical experience, phi outperformed PSA alone, was associated with high-grade PCa, and provided complementary information to MRI. Incorporation of phi into clinical practice reduced the rate of unnecessary biopsies without changing the frequency of detection of higher grade cancers.

MicroRNA-mediated gene silencing is a fundamental mechanism in the regulation of gene expression. It remains unclear how the efficiency of RNA silencing could be influenced by RNA-binding proteins associated with the microRNA-induced silencing complex (miRISC). Here we report that fused in sarcoma (FUS), an RNA-binding protein linked to neurodegenerative diseases including amyotrophic lateral sclerosis (ALS), interacts with the core miRISC component AGO2 and is required for optimal microRNA-mediated gene silencing. FUS promotes gene silencing by binding to microRNA and mRNA targets, as illustrated by its action on miR-200c and its target ZEB1. A truncated mutant form of FUS that leads its carriers to an aggressive form of ALS, R495X, impairs microRNA-mediated gene silencing. The C. elegans homolog fust-1 also shares a conserved role in regulating the microRNA pathway. Collectively, our results suggest a role for FUS in regulating the activity of microRNA-mediated silencing.

Trimodal therapy consisting of androgen deprivation, cryoablation and PD-1 blockade, as well as the combination of cryoablation and low dose anti-CTLA-4 blockade showed that local therapies with cryoablation could be considered to augment the effects of checkpoint blockade in prostate cancer.

PurposeCheckpoint therapy is now the cornerstone of treatment for patients with renal cell carcinoma (RCC) with advanced disease, but biomarkers are lacking to predict which patients will benefit. This study proposes potential immunological biomarkers that could developed for predicting therapeutic response in patients with RCC.MethodsUsing flow cytometry, RNA sequencing, and T-cell receptor (TCR) sequencing, we investigated changes in T cells in the peripheral blood of patients with advanced RCC after receiving immunotherapy. We used immunofluorescence (IF) imaging and flow cytometry to investigate how intratumoral T cells in patients’ tumors (resected months/years prior to receiving checkpoint therapy) predicted patient outcomes after immunotherapy.ResultsWe found that a small proportion of CD4 and CD8 T cells in the blood activate following checkpoint therapy, expressing the proliferation marker Ki67 and activation markers HLA-DR and CD38. Patients who had the highest increase in these HLA-DR +CD38+CD8 T cells after treatment had the best antitumor immune response and experienced clinical benefit. Using RNA sequencing, we found that while these cells expanded in most patients, their phenotype did not drastically change during treatment. However, when we analyzed the TCR repertoire of these HLA-DR +CD38+CD8+T cells, we found that only patients who clinically benefitted had a burst of new clonotypes enter this pool of activated cells. Finally, we found that abundant T cells in the untreated tumors predicted clinical benefit to checkpoint therapy on disease progression.ConclusionsTogether, these data suggest that having a strong pre-existing immune response and immediate peripheral T-cell activation after checkpoint therapy is a predictor of clinical benefit in patients with RCC.

The prostate health index (PHI) is superior to PSA and other PSA-derivatives for the detection of prostate cancer (PCa). We sought to explore the utility of PHI density for the detection of clinically-significant PCa in a contemporary cohort of men presenting for diagnostic workup of PCa.METHODS: The study cohort included patients with elevated PSA (>2 ng/mL) and negative digital rectal examination who underwent PHI testing and prostate biopsy at our institution in 2015. Serum markers were prospectively measured per standard clinical pathway. PHI was calculated as [([-2]proPSA/free PSA) x (PSA) 1/2 ], and density calculations were performed using prostate volume as determined on transrectal ultrasound. Logistic regression was used to assess the ability of serum markers to predict clinically-significant PCa, defined as any Gleason score 7 cancer or Gleason score 6 cancer in >2 cores or >50% of any positive core.RESULTS: Of 118 men with PHI testing who underwent biopsy, 47 (39.8%) were found to have clinically-significant PCa on biopsy. The median PHI density was 0.70 (IQR 0.43-1.21); it was 0.53 (IQR 0.36-0.75) in men with negative biopsy or clinically-insignificant PCa and 1.21 (IQR 0.74-1.88) in men with clinically-significant PCa (p<0.001). Clinically-significant PCa was detected in 3.6% of men in the first quartile of PHI density (<0.43), 36.7% of men in the interquartile range (0.43-1.21) of PHI density, and 80.0% of men with PHI density >1.21 (p<0.001). Using a threshold of 0.43, PHI density was 97.9% sensitive and 38.0% specific for clinically-significant PCa, and 100% sensitive for Gleason score 7 disease. Compared to PSA (AUC 0.52), PSAD (AUC 0.70), % free PSA (AUC 0.75), and PHI (AUC 0.76), PHI density demonstrated the highest discriminative ability for clinically-significant PCa (AUC 0.84).CONCLUSIONS: Based on this prospective single-center experience, PHI density could be used to avoid 38% of unnecessary biopsies while failing to detect only 2% of clinically-significant cancers.