Microbial cancer immunotherapy reprograms hematopoietic stem cells to enhance anti-tumor immunity.

Mycobacterium bovis BCG is the vaccine against tuberculosis and an immunotherapy for bladder cancer. When administered intravenously, BCG reprograms bone marrow hematopoietic stem and progenitor cells (HSPCs), leading to heterologous protection against infections. Whether HSPC-reprogramming contributes to the anti-tumor effects of BCG administered into the bladder is unknown. We demonstrate that BCG administered in the bladder in both mice and humans reprograms HSPCs to amplify myelopoiesis and functionally enhance myeloid cell antigen presentation pathways. Reconstitution of naive mice with HSPCs from bladder BCG-treated mice enhances anti-tumor immunity and tumor control, increases intratumor dendritic cell infiltration, reprograms pro-tumorigenic neutrophils, and synergizes with checkpoint blockade. We conclude that bladder BCG acts systemically, reprogramming HSPC-encoded innate immunity, highlighting the broad potential of modulating HSPC phenotypes to improve tumor immunity.

Late Recurrences Following Radical Cystectomy Have Distinct Prognostic and Management Considerations.

PURPOSE: Disease recurrence after radical cystectomy generally occurs within 2 years and has a poor prognosis. Less well defined are the outcomes in patients who experience a late recurrence (more than 3 years after radical cystectomy). We report our institutional experience with late recurrences and describe the relationships between time to recurrence, management strategies and survival. MATERIALS AND METHODS: The study cohort comprised 2,315 patients who underwent radical cystectomy for urothelial carcinoma at our center between 2000 and 2014, of whom 617 had a recurrence. Median followup for survivors was 2.6 years after recurrence (IQR 0.95-4.5). For the study we considered disease recurrence as recurrences outside the urinary tract. We compared baseline characteristics and post-recurrence management between those with recurrence 3 or less and more than 3 years after radical cystectomy. RESULTS: A total of 58 patients with late recurrence had significantly lower consensus T stage and lower frequency of nodal involvement. The average 1-year bladder cancer death rate from the time of recurrence declined from 66% to 50% to 33% for patients with recurrence times of 6 months, 2 years, and 5 years after radical cystectomy, respectively. For patients who survived at least 1 year after recurrence, the estimated survival at 5 years after recurrence was 45% for those with late recurrence and 21% for patients who had an early recurrence. Local consolidative therapy (metastasectomy or radiation) was more common in patients with late recurrence (19% vs 3.6%, p <0.0001). Cancer specific survival in early recurring cases was significantly worse than in late recurring cases in the subset receiving local consolidation (p=0.02). CONCLUSIONS: The prolonged lifespan of patients experiencing a late recurrence after radical cystectomy can be leveraged to individualize management. There is strong rationale for investigating the role of metastasectomy in the management of late recurrences.

Utility of Routine Preoperative 18F-Fluorodeoxyglucose Positron Emission Tomography/Computerized Tomography in Identifying Pathological Lymph Node Metastases at Radical Cystectomy.

PURPOSE: We determined the diagnostic performance of 18F-FDG (fluorodeoxyglucose) positron emission tomography/computerized tomography for detecting nodal metastases in patients with muscle invasive urothelial bladder cancer before radical cystectomy. MATERIALS AND METHODS: Preoperative 18F-FDG positron emission tomography/computerized tomography scans (208) were retrospectively reviewed. Scans were routinely performed in 185 patients with muscle invasive urothelial bladder cancer between August 2012 and February 2017, all of whom underwent radical cystectomy and pelvic lymph node dissection. Analyses were stratified by clinical node involvement and chemotherapy status. The diagnostic performance of 18F-FDG positron emission tomography/computerized tomography was assessed according to sensitivity, specificity, positive predictive value and negative predictive value. RESULTS: Lymph node metastases at time of pelvic lymph node dissection were present in 21.8% of those without suspicious nodes on computerized tomography (clinically node negative) and 52.6% of those with suspicious nodes on computerized tomography (clinically node positive). Median metastatic focus size was 5 mm. In clinically node negative cases 18F-FDG positron emission tomography/computerized tomography rarely detected nodal metastases (sensitivity 7% to 23%). In clinically node positive cases negative 18F-FDG positron emission tomography/computerized tomography was useful in ruling out lymph node metastases (sensitivity 92% to 100%). This study was limited by its mixed population and focus on pelvic nodal metastases only. CONCLUSIONS: 18F-FDG positron emission tomography/computerized tomography appears to be most useful for better characterization of enlarged nodes identified by computerized tomography. Routine preoperative 18F-FDG positron emission tomography/computerized tomography has limited utility in clinically node negative cases.

Chemoradiotherapy in octogenarians as primary treatment for muscle-invasive bladder cancer.

INTRODUCTION: While radical cystectomy is the gold standard for muscle-invasive bladder cancer (MIBC), in octogenarians cystectomy results in a higher perioperative mortality rate (6.8-11.1%) than in younger patients (2.2%). Trimodality therapy is a bladder-sparing regimen composed of transurethral resection of bladder tumour (TURBT) and chemoradiotherapy, with intent for salvage cystectomy, and has a 62.5-90% initial complete response rate. In this study, we evaluate TURBT and chemoradiotherapy without salvage cystectomy in medically inoperable octogenarian patients. METHODS: We identified a retrospective cohort of patients aged 80-89 years with invasive urothelial carcinoma who received combination chemoradiotherapy between 2008 and June 2014. Outcomes were evaluated by Kaplan-Meier (KM) and Cox regression. RESULTS: In 40 patients, the mean age was 84.5 years (interquartile range [IQR] 83-86). Seventeen patients received hypofractionated, low-dose radiotherapy (LD) (37.5-40 Gy), while 23 received conventionally fractionated radiotherapy (high-dose [HD]) (50-65 Gy). Mean overall survival (OS) was 20.7 months (IQR 12.75-23.25), while mean recurrence-free survival (RFS) was 13.75 months (IQR 3.75-16.5). Patients receiving HD radiotherapy showed improved OS and local RFS (LRFS) without significant differences in Grade 3-4 toxicities. Univariate Cox regression identified hydronephrosis as a predictor of worse OS and local recurrence and HD radiotherapy as a predictor of improved OS and local recurrence rates. Multivariate Cox regression identified hydronephrosis to be a significant predictor of LRFS. CONCLUSIONS: Primary chemoradiotherapy for inoperable patients with MIBC resulted in a three-year OS of 54.9% (comparable to cystectomy) and three-year RFS of 42.3%. Superior outcomes were associated with more aggressive chemoradiotherapy treatment. The results of the local control subanalyses in this study are hypothesis-generating due to the limited patient numbers in the cohort.

Invadopodia are required for cancer cell extravasation and are a therapeutic target for metastasis.

Tumor cell extravasation is a key step during cancer metastasis, yet the precise mechanisms that regulate this dynamic process are unclear. We utilized a high-resolution time-lapse intravital imaging approach to visualize the dynamics of cancer cell extravasation in vivo. During intravascular migration, cancer cells form protrusive structures identified as invadopodia by their enrichment of MT1-MMP, cortactin, Tks4, and importantly Tks5, which localizes exclusively to invadopodia. Cancer cells extend invadopodia through the endothelium into the extravascular stroma prior to their extravasation at endothelial junctions. Genetic or pharmacological inhibition of invadopodia initiation (cortactin), maturation (Tks5), or function (Tks4) resulted in an abrogation of cancer cell extravasation and metastatic colony formation in an experimental mouse lung metastasis model. This provides direct evidence of a functional role for invadopodia during cancer cell extravasation and distant metastasis and reveals an opportunity for therapeutic intervention in this clinically important process.

Imaging the impact of chemically inducible proteins on cellular dynamics in vivo.

The analysis of dynamic events in the tumor microenvironment during cancer progression is limited by the complexity of current in vivo imaging models. This is coupled with an inability to rapidly modulate and visualize protein activity in real time and to understand the consequence of these perturbations in vivo. We developed an intravital imaging approach that allows the rapid induction and subsequent depletion of target protein levels within human cancer xenografts while assessing the impact on cell behavior and morphology in real time. A conditionally stabilized fluorescent E-cadherin chimera was expressed in metastatic breast cancer cells, and the impact of E-cadherin induction and depletion was visualized using real-time confocal microscopy in a xenograft avian embryo model. We demonstrate the assessment of protein localization, cell morphology and migration in cells undergoing epithelial-mesenchymal and mesenchymal-epithelial transitions in breast tumors. This technique allows for precise control over protein activity in vivo while permitting the temporal analysis of dynamic biophysical parameters.

Case report and review of the literature: Rectal linitis plastica secondary to the lipoid cell variant of transitional cell carcinoma of the urinary bladder.

The overall 5-year survival of patients with urothelial carcinoma of the bladder (UC) is about 78%; however, there are some rare subtypes. One of these is the lipoid cell subtype, which bears a very poor prognosis. Another rare disease entity with a poor prognosis is metastasis to the lower gastrointestinal tract in the form of secondary linitis plastica of the rectum. We describe an extremely rare and unique case of rectal linitis plastica secondary to the rare lipoid cell variant of UC.

SH2 domain-containing phosphatase-2 protein-tyrosine phosphatase promotes Fc epsilon RI-induced activation of Fyn and Erk pathways leading to TNF alpha release from bone marrow-derived mast cells.

Clustering of the high affinity IgE receptor (Fc(epsilon)RI) in mast cells leads to degranulation and production of numerous cytokines and lipid mediators that promote allergic inflammation. Initiation of FFc(epsilon)RI signaling involves rapid tyrosine phosphorylation of Fc(epsilon)RI and membrane-localized adaptor proteins that recruit additional SH2 domain-containing proteins that dynamically regulate downstream signaling. SH2 domain-containing phosphatase-2 (SHP2) is a protein-tyrosine phosphatase implicated in Fc(epsilon)RI signaling, but whose function is not well defined. In this study, using a mouse model allowing temporal shp2 inactivation in bone marrow-derived mast cells (BMMCs), we provide insights into SHP2 functions in the Fc(epsilon)RI pathway. Although no overt defects in Fc(epsilon)RI-induced tyrosine phosphorylation were observed in SHP2 knock-out (KO) BMMCs, several proteins including Lyn and Syk kinases displayed extended phosphorylation kinetics compared with wild-type BMMCs. SHP2 was dispensable for Fc(epsilon)RI-induced degranulation of BMMCs, but was required for maximal activation of Erk and Jnk mitogen-activated protein kinases. SHP2 KO BMMCs displayed several phenotypes associated with reduced Fyn activity, including elevated phosphorylation of the inhibitory pY531 site in Fyn, impaired signaling to Grb2-associated binder 2, Akt/PKB, and IkappaB kinase, and decreased TNF-alpha release compared with control cells. This is likely due to elevated Lyn activity in SHP2 KO BMMCs, and the ability of Lyn to antagonize Fyn activity. Overall, our study identifies SHP2 as a positive effector of Fc(epsilon)RI-induced activation of Fyn/Grb2-associated binder 2/Akt and Ras/Erk pathways leading to TNF-alpha release from mast cells.

Contributions of F-BAR and SH2 domains of Fes protein tyrosine kinase for coupling to the FcepsilonRI pathway in mast cells.

This study investigates the roles of Fer-CIP4 homology (FCH)-Bin/amphiphysin/Rvs (F-BAR) and SH2 domains of Fes protein tyrosine kinase in regulating its activation and signaling downstream of the high-affinity immunoglobulin G (IgE) receptor (FcepsilonRI) in mast cells. Homology modeling of the Fes F-BAR domain revealed conservation of some basic residues implicated in phosphoinositide binding (R113/K114). The Fes F-BAR can bind phosphoinositides and induce tubulation of liposomes in vitro. Mutation of R113/K114 to uncharged residues (RK/QQ) caused a significant reduction in phosphoinositide binding in vitro and a more diffuse cytoplasmic localization in transfected COS-7 cells. RBL-2H3 mast cells expressing full-length Fes carrying the RK/QQ mutation show defects in FcepsilonRI-induced Fes tyrosine phosphorylation and degranulation compared to cells expressing wild-type Fes. This correlated with reduced localization to Lyn kinase-containing membrane fractions for the RK/QQ mutant compared to wild-type Fes in mast cells. The Fes SH2 domain also contributes to Fes signaling in mast cells, via interactions with the phosphorylated FcepsilonRI beta chain and the actin regulatory protein HS1. We show that Fes phosphorylates C-terminal tyrosine residues in HS1 implicated in actin stabilization. Thus, coordinated actions of the F-BAR and SH2 domains of Fes allow for coupling to FcepsilonRI signaling and potential regulation the actin reorganization in mast cells.