PTEN loss mediated Akt activation promotes prostate tumor growth and metastasis via CXCL12/CXCR4 signaling

Abstract Introduction The chemokine CXCL12, also known as SDF-1, and its receptor, CXCR4, are overexpressed in prostate cancers and in animal models of prostate-specific PTEN deletion, but their regulation is poorly understood. Loss of the tumor suppressor PTEN (phosphatase and tensin homolog) is frequently observed in cancer, resulting in the deregulation of cell survival, growth, and proliferation. We hypothesize that loss of PTEN and subsequent activation of Akt, frequent occurrences in prostate cancer, regulate the CXCL12/CXCR4 signaling axis in tumor growth and bone metastasis. Methods Murine prostate epithelial cells from PTEN+/+, PTEN +/− , and PTEN−/− (prostate specific knockdown) mice as well as human prostate cancer cell lines C4-2B, PC3, and DU145 were used in gene expression and invasion studies with Akt inhibition. Additionally, HA-tagged Akt1 was overexpressed in DU145, and tumor growth in subcutaneous and intra-tibia bone metastasis models were analyzed. Results Loss of PTEN resulted in increased expression of CXCR4 and CXCL12 and Akt inhibition reversed expression and cellular invasion. These results suggest that loss of PTEN may play a key role in the regulation of this chemokine activity in prostate cancer. Overexpression of Akt1 in DU145 resulted in increased CXCR4 expression, as well as increased proliferation and cell cycle progression. Subcutaneous injection of these cells also resulted in increased tumor growth as compared to neo controls. Akt1 overexpression reversed the osteosclerotic phenotype associated with DU145 cells to an osteolytic phenotype and enhanced intra-osseous tumor growth. Conclusions These results suggest the basis for activation of CXCL12 signaling through CXCR4 in prostate cancer driven by the loss of PTEN and subsequent activation of Akt. Akt1-associated CXCL12/CXCR4 signaling promotes tumor growth, suggesting that Akt inhibitors may potentially be employed as anticancer agents to target expansion of PC bone metastases

Large Retroperitoneal Paraganglioma Associated with Germline Mutation of the Succinate Dehydrogenase Gene

Paragangliomas (PGLs) are rare neural tumors that can be benign or malignant and often associated with familial syndromes. We present a case of a 23-year-old male with a large retroperitoneal PGL found incidentally during the workup of elevated liver enzymes. After surgical excision, the patient was found to have an autosomal dominant mutation in the succinate dehydrogenase B (SDHB) gene, which when compared to sporadic PGLs or other familial syndromes is associated with a higher risk of tumor recurrence, occult metastasis, and development of other cancers. The patient’s first-degree relatives were recommended to undergo screening for the genetic mutation

Alarmins in frozen shoulder: a molecular association between inflammation and pain

Background: The pathophysiological mechanisms behind proliferation of fibroblasts and deposition of dense collagen matrix in idiopathic frozen shoulder remain unclear. Alarmins (also known as danger signals) are endogenous molecules that are released into the extracellular milieu after infection or tissue injury and that signal cell and tissue damage. Purpose: To investigate whether the presence of alarmins is higher in patients with idiopathic frozen shoulder than in control subjects. Study Design: Controlled laboratory study. Methods: Shoulder capsule samples were collected from 10 patients with idiopathic frozen shoulder and 10 patients with unstable shoulders (control). The samples were stained with hematoxylin and eosin (H&E) and analyzed by immunohistochemistry using antibodies against alarmin molecules including high-mobility group protein B1 (HMGB1), interleukin 33, S100A8, S100A9, and the peripheral nerve marker PGP9.5. Immunoreactivities were rated in a blinded fashion from “none” to “strong.” Immunohistochemical distribution within the capsule was noted. Before surgery, patient-ranked pain frequency, severity, stiffness, and the range of passive shoulder motion were recorded and statistically analyzed. Results: Compared with control patients, patients with frozen shoulder had greater frequency and severity of self-reported pain (P = .02) and more restricted range of motion in all planes (P < .05). H&E-stained capsular tissue from frozen shoulder showed fibroblastic hypercellularity and increased subsynovial vascularity. Immunoreactivity of alarmins was significantly stronger in frozen shoulder capsules compared with control capsules (P < .05). Furthermore, the expression of the alarmin molecule HMGB1 significantly correlated (r > 0.9, P < .05) with the severity of patient-reported pain. Conclusion: This study demonstrates a potential role for key molecular danger signals in frozen shoulder and suggests an association between the expression of danger molecules and the pain experienced by patients

Adrenal Metastases as Sanctuary Sites in Advanced Renal Cancer

Involvement of the adrenal gland in kidney cancer represents a unique site of metastasis with a distinct clinical course. The cases are typically resistant to immune therapy and need local therapy management. A case series of patients with adrenal metastases was reviewed to highlight the nuances of clinical course and therapy. We reviewed renal cancer carcinoma (RCC) cases with adrenal metastases at Karmanos Cancer Center, Detroit MI. Medical records were reviewed to collect relevant case information. Next-generation sequencing, tumor mutation burden testing, and programmed death ligand biomarkers were evaluated in five cases. Twelve cases were reviewed; all were males with a median age of 49.5 years. Three patients presented with adrenal metastases only and were treated with local therapy. Three received interleukin-2 (IL-2). One patient relapsed with bilateral adrenal lesions after 11 years of remission, post-IL-2 therapy. Five cases received immune checkpoint inhibitor (ICI) and one received antivascular therapy. ICI therapy was followed by ablation of residual adrenal metastases in three patients. Genomic profiling was available in five cases. All were BAP1 and PD-L1 negative. Pathogenic mutations in PBRM1, SETD2, and VHL were noted. All patients with residual adrenal metastases responded to antivascular therapies or to local ablation. One patient died 17 years after diagnosis and 11 patients are alive at a median follow-up of 9.5 years. Adrenal metastases in RCC have a distinct clinical course. They can represent a sanctuary site of relapse/residual disease following treatment with immune therapy. Management with local therapy can induce durable remissions. Systemic management with antivascular therapies also demonstrated favorable responses. Further investigation should focus on the unique clinical course and optimal management of adrenal metastases in kidney cancer

Regulation of Gene Expression and Inhibition of Experimental Prostate Cancer Bone Metastasis by Dietary Genistein

AbstractProstate cancer frequently metastasizes to the bone, and the treatment outcome for metastatic prostate cancer has been disappointing so far. Dietary genistein, derived primarily from soy product, has been proposed to be partly responsible for the low rate of prostate cancer in Asians. Our previous studies have shown that genistein elicits pleiotropic effects on prostate cancer cells, but there are no studies documenting comprehensive gene expression profiles and antitumor effects of dietary genistein on human prostate cancer grown in human bone environment. In this study, we investigated the effects of genistein on PC3 prostate cancer cells and experimental PC3 bone tumors created by injecting PC3 cells into human bone fragments previously implanted in severe combined immunodeficient (SCID) mice (SCID human model). We found that genistein significantly inhibited PC3 bone tumor growth using both prevention and intervention strategies. By using microarray and real-time polymerase chain reaction technology, we found that genistein regulated the expression of multiple genes involved in the control of cell growth, apoptosis, and metastasis both in vitro and in vivo. For example, the expression of various metalloproteinases (MMPs) in PC3 bone tumors was inhibited by genistein treatment, whereas osteoprotegerin was upregulated. MMP immunostaining and transfection experiments also demonstrated that MMP-9 expression was inhibited in PC3 cells in vitro and PC3 bone tumors in vivo after genistein treatment. These results, particularly the in vivo results, demonstrate that dietary genistein may inhibit prostate cancer bone metastasis by regulating metastasis-related genes. Genistein may thus be a promising agent for the prevention and/or treatment of prostate cancer

PTEN Regulates PDGF Ligand Switch for β-PDGFR Signaling in Prostate Cancer

Platelet-derived growth factor (PDGF) family members are potent growth factors that regulate cell proliferation, migration, and transformation. Clinical studies have shown that both PDGF receptor β (β-PDGFR) and its ligand PDGF D are up-regulated in primary prostate cancers and bone metastases, whereas PDGF B, a classic ligand for β-PDGFR, is not frequently detected in clinical samples. In this study, we examined the role of the tumor suppressor phosphatase and tensin homologue deleted on chromosome 10 (PTEN) in the regulation of PDGF expression levels using both a prostate-specific, conditional PTEN-knockout mouse model and mouse prostate epithelial cell lines established from these mice. We found an increase in PDGF D and β-PDGFR expression levels in PTEN-null tumor cells, accompanied by a decrease in PDGF B expression. Among Akt isoforms, increased Akt3 expression was most prominent in mouse PTEN-null cells, and phosphatidylinositol 3-kinase/Akt activity was essential for the maintenance of increased PDGF D and β-PDGFR expression. In vitro deletion of PTEN resulted in a PDGF ligand switch from PDGF B to PDGF D in normal mouse prostate epithelial cells, further demonstrating that PTEN regulates this ligand switch. Similar associations between PTEN status and PDGF isoforms were noted in human prostate cancer cell lines. Taken together, these results suggest a mechanism by which loss of PTEN may promote prostate cancer progression via PDGF D/β-PDGFR signal transduction

Clinical Efficacy of Enzalutamide vs Bicalutamide Combined With Androgen Deprivation Therapy in Men With Metastatic Hormone-Sensitive Prostate Cancer: A Randomized Clinical Trial

Importance: Black patients have been underrepresented in prospective clinical trials of advanced prostate cancer. This study evaluated the efficacy of enzalutamide compared with bicalutamide, with planned subset analysis of Black patients with metastatic hormone-sensitive prostate cancer (mHSPC), which is a disease state responsive to androgen deprivation therapy (ADT). Objective: To compare the efficacy of enzalutamide vs bicalutamide in combination with ADT in men with mHSPC, with a subset analysis of Black patients. Design, Setting, and Participants: In this randomized clinical trial, a phase 2 screening design enabled a nondefinitive comparison of the primary outcome by treatment. Patients were stratified by race (Black or other) and bone pain (present or absent). Accrual of at least 30% Black patients was required. This multicenter trial was conducted at 4 centers in the US. Men with mHSPC with no history of seizures and adequate marrow, renal, and liver function were eligible. Data analysis was performed from February 2019 to March 2020. Interventions: Participants were randomized 1:1 to receive oral enzalutamide (160 mg daily) or bicalutamide (50 mg daily) in addition to ADT. Main Outcomes and Measures: The primary end point was the 7-month prostate-specific antigen (PSA) response (SMPR) rate, a previously accepted surrogate for overall survival (OS) outcome. Secondary end points included adverse reactions, time to PSA progression, and OS. Results: A total of 71 men (median [range] age, 65 [51-86] years) were enrolled; 29 (41%) were Black, 41 (58%) were White, and 1 (1%) was Asian. Thirty-six patients were randomized to receive enzalutamide, and 35 were randomized to receive bicalutamide. Twenty-six patients (37%) had bone pain and 37 patients (52%) had extensive disease. SMPR was achieved in 30 of 32 patients (94%; 95% CI, 80%-98%) taking enzalutamide and 17 of 26 patients (65%; 95% CI, 46%-81%) taking bicalutamide (P = .008) (difference, 29%; 95% CI, 5%-50%). Among Black patients, the SMPR was 93% (95% CI, 69%-99%) among those taking enzalutamide and 42% (95% CI, 19%-68%) among those taking bicalutamide (P = .009); among non-Black patients, the SMPR was 94% (95% CI, 74%-99%) among those taking enzalutamide and 86% (95% CI, 60%-96%) among those taking bicalutamide. The 12-month PSA response rates were 84% with enzalutamide and 34% with bicalutamide. Conclusions and Relevance: The findings of this randomized clinical trial comparing enzalutamide with bicalutamide suggest that enzalutamide is associated with improved outcomes compared with bicalutamide, in terms of the rate and duration of PSA response, in Black patients with mHSPC. Trial Registration: ClinicalTrials.gov Identifier: NCT02058706

Stereoselective handling of perhexiline:Implications regarding accumulation within the human myocardium

Purpose: Perhexiline is a prophylactic anti-ischaemic agent with weak calcium antagonist effect which has been increasingly utilised in the management of refractory angina. The metabolic clearance of perhexiline is modulated by CYP2D6 metaboliser status and stereoselectivity. The current study sought to (1) determine whether the acute accumulation of perhexiline in the myocardium is stereoselective and (2) investigate the relationship between duration of short-term therapy and the potential stereoselective effects of perhexiline within myocardium. Method: Patients (n = 129) from the active arm of a randomised controlled trial of preoperative perhexiline in cardiac surgery were treated with oral perhexiline for a median of 9 days. Correlates of atrial and ventricular concentrations of enantiomers were sought via univariate followed by multivariate analyses. Results: Myocardial uptake of both (+) and (−) perhexiline was greater in ventricles than in atria, and there was more rapid clearance of (−) than (+) perhexiline. The main determinants of atrial uptake of both (+) and (−) perhexiline were the plasma concentrations [(+) perhexiline: β = −0.256, p = 0.015; (−) perhexiline: β = −0.347, p = 0.001] and patients’ age [(+) perhexiline: β = 0.300, p = 0.004; (−) perhexiline: β = 0.288, p = 0.005]. Atrial uptake of (+) enantiomer also varied directly with duration of therapy (β = 0.228, p = 0.025), while atrial uptake of (−) perhexiline varied inversely with simultaneous heart rate (β = −0.240, p = 0.015). Conclusion: (1) Uptake of both perhexiline enantiomers into atrium is greater with advanced age and displays evidence of both saturability and minor stereoselectivity. (2) Atrial uptake of (−) perhexiline may selectively modulate heart rate reduction

Genome sequence of the tsetse fly (Glossina morsitans):Vector of African trypanosomiasis

Tsetse flies are the sole vectors of human African trypanosomiasis throughout sub-Saharan Africa. Both sexes of adult tsetse feed exclusively on blood and contribute to disease transmission. Notable differences between tsetse and other disease vectors include obligate microbial symbioses, viviparous reproduction, and lactation. Here, we describe the sequence and annotation of the 366-megabase Glossina morsitans morsitans genome. Analysis of the genome and the 12,308 predicted protein-encoding genes led to multiple discoveries, including chromosomal integrations of bacterial (Wolbachia) genome sequences, a family of lactation-specific proteins, reduced complement of host pathogen recognition proteins, and reduced olfaction/chemosensory associated genes. These genome data provide a foundation for research into trypanosomiasis prevention and yield important insights with broad implications for multiple aspects of tsetse biology.IS

Loss of Let-7 Up-Regulates EZH2 in Prostate Cancer Consistent with the Acquisition of Cancer Stem Cell Signatures That Are Attenuated by BR-DIM

The emergence of castrate-resistant prostate cancer (CRPC) contributes to the high mortality of patients diagnosed with prostate cancer (PCa), which in part could be attributed to the existence and the emergence of cancer stem cells (CSCs). Recent studies have shown that deregulated expression of microRNAs (miRNAs) contributes to the initiation and progression of PCa. Among several known miRNAs, let-7 family appears to play a key role in the recurrence and progression of PCa by regulating CSCs; however, the mechanism by which let-7 family contributes to PCa aggressiveness is unclear. Enhancer of Zeste homolog 2 (EZH2), a putative target of let-7 family, was demonstrated to control stem cell function. In this study, we found loss of let-7 family with corresponding over-expression of EZH2 in human PCa tissue specimens, especially in higher Gleason grade tumors. Overexpression of let-7 by transfection of let-7 precursors decreased EZH2 expression and repressed clonogenic ability and sphere-forming capacity of PCa cells, which was consistent with inhibition of EZH2 3′UTR luciferase activity. We also found that the treatment of PCa cells with BR-DIM (formulated DIM: 3,3′-diindolylmethane by Bio Response, Boulder, CO, abbreviated as BR-DIM) up-regulated let-7 and down-regulated EZH2 expression, consistent with inhibition of self-renewal and clonogenic capacity. Moreover, BR-DIM intervention in our on-going phase II clinical trial in patients prior to radical prostatectomy showed upregulation of let-7 consistent with down-regulation of EZH2 expression in PCa tissue specimens after BR-DIM intervention. These results suggest that the loss of let-7 mediated increased expression of EZH2 contributes to PCa aggressiveness, which could be attenuated by BR-DIM treatment, and thus BR-DIM is likely to have clinical impact