CPSF3 inhibition blocks pancreatic cancer cell proliferation through disruption of core histone mRNA processing.

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with limited effective treatment options, potentiating the importance of uncovering novel drug targets. Here, we target cleavage and polyadenylation specificity factor 3 (CPSF3), the 3' endonuclease that catalyzes mRNA cleavage during polyadenylation and histone mRNA processing. We find that CPSF3 is highly expressed in PDAC and is associated with poor prognosis. CPSF3 knockdown blocks PDAC cell proliferation and colony formation in vitro and tumor growth in vivo. Chemical inhibition of CPSF3 by the small molecule JTE-607 also attenuates PDAC cell proliferation and colony formation, while it has no effect on cell proliferation of nontransformed immortalized control pancreatic cells. Mechanistically, JTE-607 induces transcriptional readthrough in replication-dependent histones, reduces core histone expression, destabilizes chromatin structure, and arrests cells in the S-phase of the cell cycle. Therefore, CPSF3 represents a potential therapeutic target for the treatment of PDAC.

Does the urinary microbiome profile change after treatment of bladder cancer?

INTRODUCTION: We sought to investigate the change in the urinary microbiome profile after transurethral resection of bladder tumor (TURBT). METHODS: Urine specimens were collected from consecutive patients with bladder cancer. Patients were divided into those with bladder tumors ("Tumor group": de novo tumors or recurrent/progressed after TURBT ± intravesical therapy) versus those without evidence of recurrence after treatment "No Recurrent Tumor group". Samples were analyzed using 16S rRNA sequencing. Alteration in the urinary microbiome was described in terms of alpha (diversity within a sample measured by Observed, Chao, Shannon, and Simpson indices), beta diversities (diversity among different samples measured by Brady Curtis Diversity index), and differential abundance of bacteria at the genus level. Analyses were adjusted for gender, method of preservation (frozen vs preservative), and method of collection (mid-stream vs. catheter). RESULTS: Sixty-eight samples were analyzed (42 in "Tumor" vs 26 in "No Recurrent Tumor" groups). The median age was 70 years (IQR 64-74) and 85% were males. All patients in the "No Recurrent Tumor" group had non-muscle invasive bladder cancer and 85% received BCG compared to 69% and 43% for the "Tumor" group, respectively. There was no significant difference in alpha diversity (p > 0.05). Beta diversity was significantly different (p = 0.04). Veillonella and Bifidobacterium were more abundant in the "Tumor" group (> 2FC, p = 0.0002), while Escherichia-Shigella (> 2FC, p = 0.0002) and Helococcus (> 2FC, p = 0.0008) were more abundant in the "No Recurrent Tumor" group. CONCLUSION: Bladder cancer patients with no recurrence and/or progression exhibited a different urinary microbiome profile compared to those with tumors.

PTEN Loss Expands the Histopathologic Diversity and Lineage Plasticity of Lung Cancers Initiated by Rb1/Trp53 Deletion.

INTRODUCTION: High-grade neuroendocrine tumors of the lung such as SCLC are recalcitrant cancers for which more effective systemic therapies are needed. Despite their histopathologic and molecular heterogeneity, they are generally treated as a single disease entity with similar chemotherapy regimens. Whereas marked clinical responses can be observed, they are short-lived. Inter- and intratumoral heterogeneity is considered a confounding factor in these unsatisfactory clinical outcomes, yet the origin of this heterogeneity and its impact on therapeutic responses is not well understood. METHODS: New genetically engineered mouse models are used to test the effects of PTEN loss on the development of lung tumors initiated by Rb1 and Trp53 tumor suppressor gene deletion. RESULTS: Complete PTEN loss drives more rapid tumor development with a greater diversity of tumor histopathology ranging from adenocarcinoma to SCLC. PTEN loss also drives transcriptional heterogeneity as marked lineage plasticity is observed within histopathologic subtypes. Spatial profiling indicates transcriptional heterogeneity exists both within and among tumor foci with transcriptional patterns correlating with spatial position, implying that the growth environment influences gene expression. CONCLUSIONS: These results identify PTEN loss as a clinically relevant genetic alteration driving the molecular and histopathologic heterogeneity of neuroendocrine lung tumors initiated by Rb1/Trp53 mutations.

Fungal mycobiome drives IL-33 secretion and type 2 immunity in pancreatic cancer.

TH2 cells and innate lymphoid cells 2 (ILC2) can stimulate tumor growth by secreting pro-tumorigenic cytokines such as interleukin-4 (IL-4), IL-5, and IL-13. However, the mechanisms by which type 2 immune cells traffic to the tumor microenvironment are unknown. Here, we show that oncogenic KrasG12D increases IL-33 expression in pancreatic ductal adenocarcinoma (PDAC) cells, which recruits and activates TH2 and ILC2 cells. Correspondingly, cancer-cell-specific deletion of IL-33 reduces TH2 and ILC2 recruitment and promotes tumor regression. Unexpectedly, IL-33 secretion is dependent on the intratumoral fungal mycobiome. Genetic deletion of IL-33 or anti-fungal treatment decreases TH2 and ILC2 infiltration and increases survival. Consistently, high IL-33 expression is observed in approximately 20% of human PDAC, and expression is mainly restricted to cancer cells. These data expand our knowledge of the mechanisms driving PDAC tumor progression and identify therapeutically targetable pathways involving intratumoral mycobiome-driven secretion of IL-33.

Genes Relevant to Tissue Response to Cancer Therapy Display Diurnal Variation in mRNA Expression in Human Oral Mucosa.

BACKGROUND: To address a critical gap for application of cancer chronotherapy of when would be the best time(s) for treating an individual cancer patient, we conducted a pilot study to characterize diurnal variations of gene expression in oral mucosal tissue, which is vulnerable to damage from cancer therapies. METHODS: We conducted RNA-seq assay on individual oral mucosal samples collected from 11 healthy volunteers every 4 hours (6 time points). Using a cosine-based method, we estimated the individual and average values of peak-time and amplitude for each gene. Correlations between gene expression peak-times and age was examined, adjusting for individual's sleep timing. RESULTS: Among candidate gene pathways that are relevant to treatment response, 7 of 16 genes (PER3, CIART, TEF, PER1, PER2, CRY2, ARNTL) involved in circadian regulation and 1 of 118 genes (WEE1) involved in cell cycle regulation achieved p-value ≤ 0.1 and relative amplitude>0.1. The average peak times were approximately 10:15 for PER3, CIART and TEF, 10:45 for PER1, 13:00 for WEE1, PER2 and CRY2, and 19:30 for ARNTL. Ranges in peak times across individuals differed by gene (e.g., 8 hours for PER1; 16.7 hours for WEE1). Older people had later peak times for PER1 (r = 0.77, p = 0.03) and PER3 (r = 0.69, p-value = 0.06). CONCLUSION: In oral mucosa, expression of some genes relevant to treatment response displayed diurnal variation. These genes may be candidates for development of biomarkers for optimizing individual timing of cancer therapy using non-invasively collected oral mucosa.

Investigating the association between the urinary microbiome and bladder cancer: An exploratory study.

INTRODUCTION: We sought to investigate the association between the urinary microbiome and bladder cancer, including the difference between nonmuscle-invasive (NMIBC) and muscle-invasive (MIBC) bladder cancer, and Bacillus Calmette Guerin (BCG) responsive vs. BCG-refractory NMIBC. METHODS: Urine specimens were collected from consecutive patients with bladder cancer and healthy volunteers. Urine samples were analyzed using 16S rRNA sequencing to identify and compare any present bacteria. Alteration in the urinary microbiome was described in terms of alpha (diversity of populations within a sample) and beta diversities (differences between populations among different samples). Analyses were corrected for age, sex, method of sample preservation, and method of collection (mid-stream catch vs. catheterized urine). RESULTS: Fifty-three samples (43 patients with bladder cancer, and 10 controls) were included. For bladder cancer patients, mean age was 70 years, 7 (16%) were females; and 29 (67%) had NMIBC. Among patients with NMIBC, 11 (38%) patients received BCG, 6 of which had recurrence or progression after a median follow up of 13 months. Comparing the microbiome of bladder cancer patients vs. healthy controls, beta-diversity was significantly different, with Actinomyces, Achromobacter, Brevibacterium, and Brucella significantly more abundant in urine samples of bladder cancer patients. Comparing NMIBC and MIBC, Hemophilus and Veillonella were significantly more abundant in urine of MIBC patients, while Cupriavidus was significantly more abundant in NMIBC patients. Among NMIBC patients, Serratia and Brochothrix, Negativicoccus, Escherichia-Shigella, and Pseudomonas were significantly more abundant in patients who responded to BCG in comparison to those who did not. CONCLUSION: Urinary microbiome varied between patients with bladder cancer and healthy controls. Moreover, urinary microbial profiles differed among patient with NMIBC vs. MIBC, and among BCG responsive vs. BCG refractory NMIBC.

Efficacy and Safety of Pembrolizumab in Combination With Bevacizumab and Oral Metronomic Cyclophosphamide in the Treatment of Recurrent Ovarian Cancer: A Phase 2 Nonrandomized Clinical Trial.

IMPORTANCE: Treatment options for recurrent ovarian cancer are of limited clinical benefit and adversely affect patient quality of life, representing an unmet need for tolerable effective therapies. OBJECTIVE: To assess the efficacy and safety of a combination of pembrolizumab with bevacizumab and oral metronomic cyclophosphamide in patients with recurrent platinum-sensitive, platinum-resistant, or refractory epithelial ovarian, fallopian tube, or primary peritoneal cancer. DESIGN, SETTING, AND PARTICIPANTS: This open-label, single-arm phase 2 cohort study enrolled patients from September 6, 2016, to June 27, 2018, at a single institution in the United States. Eligible patients had recurrent ovarian cancer, measurable disease per immune-related Response Evaluation Criteria In Solid Tumors (irRECIST), and Eastern Cooperative Oncology Group performance status of 0 to 1. Data were analyzed from September 6, 2016, to February 20, 2020. INTERVENTIONS: Patients received intravenous pembrolizumab, 200 mg, and bevacizumab, 15 mg/kg, every 3 weeks and oral cyclophosphamide, 50 mg, once daily during the treatment cycle until disease progression, unacceptable toxic effects, or withdrawal of consent. MAIN OUTCOMES AND MEASURES: Primary outcomes were objective response rate (ORR) and progression-free survival (PFS). RESULTS: Of the 40 women enrolled, 30 (75.0%) had platinum-resistant and 10 (25.0%) had platinum-sensitive ovarian cancer with a mean (SD) age of 62.2 (9.4) years. Three women (7.5%) had complete responses, 16 (40.0%) had partial responses, and 19 (47.5%) had stable disease in response to treatment based on irRECIST criteria, with an ORR of 47.5%, clinical benefit in 38 (95.0%), and durable response in 10 (25.0%). Median PFS was 10.0 (90% CI, 6.5-17.4) months. The most common grade 3 to 4 treatment-related adverse events were hypertension (6 [15.0%]) and lymphopenia (3 [7.5%]). The most frequently reported adverse events included fatigue (18 [45.0%]), diarrhea (13 [32.5%]), and hypertension (11 [27.5%]). CONCLUSIONS AND RELEVANCE: In this phase 2 nonrandomized clinical trial, the combination of pembrolizumab with bevacizumab and oral cyclophosphamide was well tolerated and demonstrated clinical benefit in 95.0% and durable treatment responses (>12 months) in 25.0% of patients with recurrent ovarian cancer. This combination may represent a future treatment strategy for recurrent ovarian cancer. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02853318.

Inhibition of LSD1 in MDS progenitors restores differentiation of CD141Hi conventional dendritic cells.

The use of immunotherapy to treat patients with myelodysplastic syndromes (MDS) shows promise but is limited by our incomplete understanding of the immunologic milieu. In solid tumors, CD141Hi conventional dendritic cells (CD141Hi cDCs) are necessary for antitumor immunosurveillance and the response to immunotherapy. Here, we found that CD141Hi cDCs are reduced in MDS bone marrow and based on the premise established in solid tumors, we hypothesized that reduced numbers of CD141Hi cDCs are associated with inferior overall survival in MDS patients. We found that MDS patients with reduced numbers of CD141Hi cDCs, but not other DC populations, showed reduced overall survival. To examine the basis for reduction in CD141Hi cDCs, we found fewer numbers of progenitors committed to DC differentiation in the MDS bone marrow and these progenitors expressed lower levels of interferon regulatory factor-8 (IRF8), a master regulator of CD141Hi cDC differentiation. To rescue impaired CD141Hi cDC differentiation, we used pharmacologic inhibition of lysine-specific demethylase 1A (LSD1) to promote CD141Hi cDC differentiation by MDS progenitors. These data reveal a previously unrecognized element of the MDS immunologic milieu. Epigenetic regulation of CD141Hi cDC differentiation offers an intriguing opportunity for intervention and a potential adjunct to immunotherapy for patients with MDS.

Rb1 and Trp53 cooperate to suppress prostate cancer lineage plasticity, metastasis, and antiandrogen resistance.

Prostate cancer relapsing from antiandrogen therapies can exhibit variant histology with altered lineage marker expression, suggesting that lineage plasticity facilitates therapeutic resistance. The mechanisms underlying prostate cancer lineage plasticity are incompletely understood. Studying mouse models, we demonstrate that Rb1 loss facilitates lineage plasticity and metastasis of prostate adenocarcinoma initiated by Pten mutation. Additional loss of Trp53 causes resistance to antiandrogen therapy. Gene expression profiling indicates that mouse tumors resemble human prostate cancer neuroendocrine variants; both mouse and human tumors exhibit increased expression of epigenetic reprogramming factors such as Ezh2 and Sox2. Clinically relevant Ezh2 inhibitors restore androgen receptor expression and sensitivity to antiandrogen therapy. These findings uncover genetic mutations that enable prostate cancer progression; identify mouse models for studying prostate cancer lineage plasticity; and suggest an epigenetic approach for extending clinical responses to antiandrogen therapy.

Intratumoral and Intertumoral Genomic Heterogeneity of Multifocal Localized Prostate Cancer Impacts Molecular Classifications and Genomic Prognosticators.

BACKGROUND: Next-generation sequencing is revealing genomic heterogeneity in localized prostate cancer (CaP). Incomplete sampling of CaP multiclonality has limited the implications for molecular subtyping, stratification, and systemic treatment. OBJECTIVE: To determine the impact of genomic and transcriptomic diversity within and among intraprostatic CaP foci on CaP molecular taxonomy, predictors of progression, and actionable therapeutic targets. DESIGN, SETTING, AND PARTICIPANTS: Four consecutive patients with clinically localized National Comprehensive Cancer Network intermediate- or high-risk CaP who did not receive neoadjuvant therapy underwent radical prostatectomy at Roswell Park Cancer Institute in June-July 2014. Presurgical information on CaP content and a customized tissue procurement procedure were used to isolate nonmicroscopic and noncontiguous CaP foci in radical prostatectomy specimens. Three cores were obtained from the index lesion and one core from smaller lesions. RNA and DNA were extracted simultaneously from 26 cores with ≥90% CaP content and analyzed using whole-exome sequencing, single-nucleotide polymorphism arrays, and RNA sequencing. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Somatic mutations, copy number alternations, gene expression, gene fusions, and phylogeny were defined. The impact of genomic alterations on CaP molecular classification, gene sets measured in Oncotype DX, Prolaris, and Decipher assays, and androgen receptor activity among CaP cores was determined. RESULTS AND LIMITATIONS: There was considerable variability in genomic alterations among CaP cores, and between RNA- and DNA-based platforms. Heterogeneity was found in molecular grouping of individual CaP foci and the activity of gene sets underlying the assays for risk stratification and androgen receptor activity, and was validated in independent genomic data sets. Determination of the implications for clinical decision-making requires follow-up studies. CONCLUSIONS: Genomic make-up varies widely among CaP foci, so care should be taken when making treatment decisions based on a single biopsy or index lesions. PATIENT SUMMARY: We examined the molecular composition of individual cancers in a patient's prostate. We found a lot of genetic diversity among these cancers, and concluded that information from a single cancer biopsy is not sufficient to guide treatment decisions.

Genomic profiling is predictive of response to cisplatin treatment but not to PI3K inhibition in bladder cancer patient-derived xenografts.

PURPOSE: Effective systemic therapeutic options are limited for bladder cancer. In this preclinical study we tested whether bladder cancer gene alterations may be predictive of treatment response. EXPERIMENTAL DESIGN: We performed genomic profiling of two bladder cancer patient derived tumor xenografts (PDX). We optimized the exome sequence analysis method to overcome the mouse genome interference. RESULTS: We identified a number of somatic mutations, mostly shared by the primary tumors and PDX. In particular, BLCAb001, which is less responsive to cisplatin than BLCAb002, carried non-sense mutations in several genes associated with cisplatin resistance, including MLH1, BRCA2, and CASP8. Furthermore, RNA-Seq analysis revealed the overexpression of cisplatin resistance associated genes such as SLC7A11, TLE4, and IL1A in BLCAb001. Two different PIK3CA mutations, E542K and E545K, were identified in BLCAb001 and BLCAb002, respectively. Thus, we tested whether the genomic profiling was predictive of response to a dual PI3K/mTOR targeting agent, LY3023414. Despite harboring similar PIK3CA mutations, BLCAb001 and BLCAb002 exhibited differential response, both in vitro and in vivo. Sustained target modulation was observed in the sensitive model BLCAb002 but not in BLCAb001, as well as decreased autophagy. Interestingly, computational modelling of mutant structures and affinity binding to PI3K revealed that E542K mutation was associated with weaker drug binding than E545K. CONCLUSIONS: Our results suggest that the presence of activating PIK3CA mutations may not necessarily predict in vivo treatment response to PI3K targeted therapies, while specific gene alterations may be predictive for cisplatin response in bladder cancer models and, potentially, in patients as well.