Bone is the most common site of prostate cancer (PCa) progression to a therapy-resistant, lethal phenotype. We found that blockade of fibroblast growth factor receptors (FGFRs) with the receptor ...tyrosine kinase inhibitor dovitinib has clinical activity in a subset of men with castration-resistant PCa and bone metastases. Our integrated analyses suggest that FGF signaling mediates a positive feedback loop between PCa cells and bone cells and that blockade of FGFR1 in osteoblasts partially mediates the antitumor activity of dovitinib by improving bone quality and by blocking PCa cell-bone cell interaction. These findings account for clinical observations such as reductions in lesion size and intensity on bone scans, lymph node size, and tumor-specific symptoms without proportional declines in serum prostate-specific antigen concentration. Our findings suggest that targeting FGFR has therapeutic activity in advanced PCa and provide direction for the development of therapies with FGFR inhibitors.
The signaling mechanisms between prostate cancer cells and infiltrating immune cells may illuminate novel therapeutic approaches. Here, utilizing a prostate adenocarcinoma model driven by loss of ...Pten and Smad4, we identify polymorphonuclear myeloid-derived suppressor cells (MDSC) as the major infiltrating immune cell type, and depletion of MDSCs blocks progression. Employing a novel dual reporter prostate cancer model, epithelial and stromal transcriptomic profiling identified CXCL5 as a cancer-secreted chemokine to attract CXCR2-expressing MDSCs, and, correspondingly, pharmacologic inhibition of CXCR2 impeded tumor progression. Integrated analyses identified hyperactivated Hippo-YAP signaling in driving CXCL5 upregulation in cancer cells through the YAP-TEAD complex and promoting MDSC recruitment. Clinicopathologic studies reveal upregulation and activation of YAP1 in a subset of human prostate tumors, and the YAP1 signature is enriched in primary prostate tumor samples with stronger expression of MDSC-relevant genes. Together, YAP-driven MDSC recruitment via heterotypic CXCL5-CXCR2 signaling reveals an effective therapeutic strategy for advanced prostate cancer.
We demonstrate a critical role of MDSCs in prostate tumor progression and discover a cancer cell nonautonomous function of the Hippo-YAP pathway in regulation of CXCL5, a ligand for CXCR2-expressing MDSCs. Pharmacologic elimination of MDSCs or blocking the heterotypic CXCL5-CXCR2 signaling circuit elicits robust antitumor responses and prolongs survival.
White adipose tissue (WAT) overgrowth in obesity is linked with increased aggressiveness of certain cancers. Adipose stromal cells (ASCs) can become mobilized from WAT, recruited by tumours and ...promote cancer progression. Mechanisms underlying ASC trafficking are unclear. Here we demonstrate that chemokines CXCL1 and CXCL8 chemoattract ASC by signalling through their receptors, CXCR1 and CXCR2, in cell culture models. We further show that obese patients with prostate cancer have increased epithelial CXCL1 expression. Concomitantly, we observe that cells with ASC phenotype are mobilized and infiltrate tumours in obese patients. Using mouse models, we show that the CXCL1 chemokine gradient is required for the obesity-dependent tumour ASC recruitment, vascularization and tumour growth promotion. We demonstrate that αSMA expression in ASCs is induced by chemokine signalling and mediates the stimulatory effects of ASCs on endothelial cells. Our data suggest that ASC recruitment to tumours, driven by CXCL1 and CXCL8, promotes prostate cancer progression.
Advances in prostate cancer lag behind other tumor types partly due to the paucity of models reflecting key milestones in prostate cancer progression. Therefore, we develop clinically relevant ...prostate cancer models.
Since 1996, we have generated clinically annotated patient-derived xenografts (PDXs; the MDA PCa PDX series) linked to specific phenotypes reflecting all aspects of clinical prostate cancer.
We studied two cell line-derived xenografts and the first 80 PDXs derived from 47 human prostate cancer donors. Of these, 47 PDXs derived from 22 donors are working models and can be expanded either as cell lines (MDA PCa 2a and 2b) or PDXs. The histopathologic, genomic, and molecular characteristics (androgen receptor, ERG, and
loss) maintain fidelity with the human tumor and correlate with published findings. PDX growth response to mouse castration and targeted therapy illustrate their clinical utility. Comparative genomic hybridization and sequencing show significant differences in oncogenic pathways in pairs of PDXs derived from different areas of the same tumor. We also identified a recurrent focal deletion in an area that includes the speckle-type POZ protein-like (
) gene in PDXs derived from seven human donors of 28 studied (25%).
is a
paralog, and
mutations define a molecular subclass of prostate cancer.
deletions are found in 7% of The Cancer Genome Atlas prostate cancers, which suggests that our cohort is a reliable platform for targeted drug development.
The MDA PCa PDX series is a dynamic resource that captures the molecular landscape of prostate cancers progressing under novel treatments and enables optimization of prostate cancer-specific, marker-driven therapy.
Androgen deprivation is the standard treatment for advanced prostate cancer (PCa), but most patients ultimately develop resistance and tumor recurrence. We found that MYB is transcriptionally ...activated by androgen deprivation therapy or genetic silencing of the androgen receptor (AR). MYB silencing inhibited PCa growth in culture and xenografts in mice. Microarray data revealed that c-Myb and AR shared a subset of target genes that encode DNA damage response (DDR) proteins, suggesting that c-Myb may supplant AR as the dominant regulator of their common DDR target genes in AR inhibition-resistant or AR-negative PCa. Gene signatures including AR, MYB, and their common DDR-associated target genes positively correlated with metastasis, castration resistance, tumor recurrence, and decreased survival in PCa patients. In culture and in xenograft-bearing mice, a combination strategy involving the knockdown of MYB, BRCA1, or TOPBP1 or the abrogation of cell cycle checkpoint arrest with AZD7762, an inhibitor of the checkpoint kinase Chk1, increased the cytotoxicity of the polyadenosine 5'-diphosphate (ADP)-ribose polymerase (PARP) inhibitor olaparib in PCa cells. Our results reveal new mechanism-based therapeutic approaches for PCa by targeting PARP and the DDR pathway involving c-Myb, TopBP1, ataxia telangiectasia mutated- and Rad3-related (ATR), and Chk1.
Morphologically heterogeneous prostate cancers that behave clinically like small-cell prostate cancers (SCPC) share their chemotherapy responsiveness. We asked whether these clinically defined, ...morphologically diverse, "aggressive variant prostate cancer (AVPC)" also share molecular features with SCPC.
Fifty-nine prostate cancer samples from 40 clinical trial participants meeting AVPC criteria, and 8 patient-tumor derived xenografts (PDX) from 6 of them, were stained for markers aberrantly expressed in SCPC. DNA from 36 and 8 PDX was analyzed by Oncoscan for copy number gains (CNG) and losses (CNL). We used the AVPC PDX to expand observations and referenced publicly available datasets to arrive at a candidate molecular signature for the AVPC.
Irrespective of morphology, Ki67 and Tp53 stained ≥10% cells in 80% and 41% of samples, respectively. RB1 stained <10% cells in 61% of samples and AR in 36%. MYC (surrogate for 8q) CNG and RB1 CNL showed in 54% of 44 samples each and PTEN CNL in 48%. All but 1 of 8 PDX bore Tp53 missense mutations. RB1 CNL was the strongest discriminator between unselected castration-resistant prostate cancer (CRPC) and the AVPC. Combined alterations in RB1, Tp53, and/or PTEN were more frequent in the AVPC than in unselected CRPC and in The Cancer Genome Atlas samples.
Clinically defined AVPC share molecular features with SCPC and are characterized by combined alterations in RB1, Tp53, and/or PTEN.
To evaluate the pathologic features after radical prostatectomy to determine if the length of positive surgical margin (PSM) and the highest Gleason grade within the tumor at the PSM could risk ...stratify patients for biochemical recurrence (BCR).
We performed a retrospective, matched, cohort study to identify patients with pathologically organ-confined (pT2) tumors and negative nodes (pN0/Nx), receiving no adjuvant therapy. Specimens underwent single pathologist review. BCR-free survival was estimated using the Kaplan-Meier method and compared between subgroups using two-sided log-rank test. Using Classification and Regression Tree analysis (CART), we identified an optimal cutoff for the PSM length which differentiated risk for BCR. Cox proportional hazards regression models were fit to assess the association between variables and BCR-free survival.
Two-hundred PSM patients were matched to 200 patients with negative surgical margins (NSM). Median follow-up was 64 months. 5 year BCR-free survival was 90% (95% CI 84-97%) in the NSM group and 70% (95% CI 63-79%) in the PSM group. There was an increased risk of BCR with any PSM. Multivariable analysis demonstrated an association with length of PSM ( > 1 mm vs. ≤ 1 mm, HR 2.29; 95% CI 1.2-4.5) and having a highest Gleason grade of the cancer focus at the margin ≥ 4 (HR 6.8; 95% CI 1.6-29).
We demonstrated that patients with pathologic T2 tumors with PSM > 1 mm or a Gleason grade of tumor focus at the margin ≥ 4 are at elevated risk for BCR. However, this study suggests that patients with pT2 tumors with positive surgical margins have a relatively low risk of biochemical recurrence and adjuvant radiation may be over treating this sub population. The subsets at greatest risk for BCR may benefit from more frequent PSA monitoring to direct salvage therapies.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
SummaryBackgroundTaxane–platinum combinations have shown promising activity in metastatic castration-resistant prostate cancers in single-group clinical studies but not in randomised trials. Distinct ...biological subsets of the disease might derive the greatest benefit from the addition of platinum. We aimed to determine whether adding carboplatin to cabazitaxel would improve the outcomes of men with metastatic castration-resistant prostate cancer. MethodsWe did a phase 1–2, open label, randomised study at two centres in men with progressive metastatic castration-resistant prostate cancer. In phase 1, patients received intravenous cabazitaxel 20–25 mg/m 2 and intravenous carboplatin area under the curve (AUC) 3–4 mg/mL per min every 21 days. The maximum tolerated dose was defined as the highest dose cohort studied in which one of six or fewer patients experienced a dose-limiting toxicity. In phase 2, patients were randomly assigned (1:1) centrally by a computerised algorithm to intravenous cabazitaxel 25 mg/m 2 with or without intravenous carboplatin AUC 4 mg/mL per min. All patients received growth factor support and oral prednisone 10 mg daily. The primary endpoints were the maximum tolerated dose of the combination in phase 1 and investigator-assessed progression-free survival in phase 2. This trial is registered at ClinicalTrials.gov, number NCT01505868. FindingsBetween Aug 17, 2012, and May 11, 2015, nine patients completed phase 1 as planned, and 160 were randomly assigned to cabazitaxel (n=79) or cabazitaxel plus carboplatin (n=81) in phase 2. During phase I, grade 3 adverse events were anaemia (n=2), fatigue (n=1), thrombocytopenia (n=1), hypomagnesaemia (n=1), diarrhoea (n=1), hypokalaemia (n=1), anorexia (n=1), and dehydration (n=1), and no grade 4 adverse events occurred. No dose-limiting toxicities were observed, therefore, a maximum tolerated dose of cabazitaxel of 25 mg/m 2 and carboplatin of AUC 4 mg/mL per min was selected for phase 2. At a median follow-up of 31·0 months (IQR 20·5–37·1), the combination improved the median progression-free survival from 4·5 months (95% CI 3·5–5·7) to 7·3 months (95% CI 5·5–8·2; hazard ratio 0·69, 95% CI 0·50–0·95, p=0·018). In the phase 2 study, the most common grade 3–5 adverse events were fatigue (7 9% of 79 in the cabazitaxel group vs 16 20% of 81 in the combination group), anaemia (3 4% vs 19 23%), neutropenia (3 4% vs 13 16%), and thrombocytopenia (1 1% vs 11 14%). There were no treatment-related deaths. InterpretationCarboplatin added to cabazitaxel showed improved clinical efficacy compared with cabazitaxel alone for men with metastatic castration-resistant prostate cancer. Although adverse events were more common with the combination, the treatment was safe and generally well tolerated. Our data suggest that taxane–platinum combinations have a clinically beneficial role in advanced prostate cancer and a randomised phase 3 study is planned. FundingSanofi Genzyme, University of Texas MD Anderson Cancer Center Prostate Cancer Moon Shot Program, and Solon Scott III Prostate Cancer Research Fund.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Cytochrome P450 17α-hydroxylase/17,20-lyase (CYP17A1) is a validated treatment target for the treatment of metastatic castration-resistant prostate cancer (CRPC). Abiraterone acetate (AA) inhibits ...both 17α-hydroxylase (hydroxylase) and 17,20-lyase (lyase) reactions catalyzed by CYP17A1 and thus depletes androgen biosynthesis. However, coadministration of prednisone is required to suppress the mineralocorticoid excess and cortisol depletion that result from hydroxylase inhibition. VT-464, a nonsteroidal small molecule, selectively inhibits CYP17A1 lyase and therefore does not require prednisone supplementation. Administration of VT-464 in a metastatic CRPC patient presenting with high tumoral expression of both androgen receptor (AR) and CYP17A1, showed significant reduction in the level of both dehydroepiandrosterone (DHEA) and serum PSA. Treatment of a CRPC patient-derived xenograft, MDA-PCa-133 expressing H874Y AR mutant with VT-464, reduced the increase in tumor volume in castrate male mice more than twice as much as the vehicle (P < 0.05). Mass spectrometry analysis of post-treatment xenograft tumor tissues showed that VT-464 significantly decreased intratumoral androgens but not cortisol. VT-464 also reduced AR signaling more effectively than abiraterone in cultured PCa cells expressing T877A AR mutant. Collectively, this study suggests that VT-464 therapy can effectively treat CRPC and be used in precision medicine based on androgen receptor mutation status.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Highlights • The pathogenesis of HTLV-1-associated infective dermatitis (ID)() is unclear. • Patients with ID may subsequently present with ATLL and/or HAM/TSP. • ID histopathology overlaps with ...lymphoid reactive and neoplastic proliferations. • ID demonstrates low frequency of Tregs as opposed to other inflammatory conditions. • Decreased numbers of Tregs may have a role in the pathogenesis of this disease.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK