Multi-ancestry genome-wide association study of major depression aids locus discovery, fine mapping, gene prioritization and causal inference.

Most genome-wide association studies (GWAS) of major depression (MD) have been conducted in samples of European ancestry. Here we report a multi-ancestry GWAS of MD, adding data from 21 cohorts with 88,316 MD cases and 902,757 controls to previously reported data. This analysis used a range of measures to define MD and included samples of African (36% of effective sample size), East Asian (26%) and South Asian (6%) ancestry and Hispanic/Latin American participants (32%). The multi-ancestry GWAS identified 53 significantly associated novel loci. For loci from GWAS in European ancestry samples, fewer than expected were transferable to other ancestry groups. Fine mapping benefited from additional sample diversity. A transcriptome-wide association study identified 205 significantly associated novel genes. These findings suggest that, for MD, increasing ancestral and global diversity in genetic studies may be particularly important to ensure discovery of core genes and inform about transferability of findings.

Early Lipid Metabolic Effects of the Anti-Psychotic Drug Olanzapine on Weight Gain and the Associated Gene Expression.

Background: Atypical antipsychotics such as olanzapine often cause metabolic side effects such as obesity and diabetes, leading to an increased risk of nonalcoholic fatty liver disease. The aim of the present study was to investigate the effects of olanzapine treatment on hepatic lipid metabolism and its possible relationship with adipose tissue status. Methods: Using a female rat model, we investigated the effects of chronic olanzapine administration on the regulation of carbohydrate and lipid metabolism including lipid biosynthesis, oxidation, efflux, and lipolysis in liver and adipose tissue. Results: The body weight, liver mass and visceral adiposity after olanzapine treatment (2 mg/kg) for five weeks were not significantly different compared with vehicle controls. The serum level of triglycerides was higher in the vehicle controls than in olanzapine-treated rats. Unexpectedly, olanzapine treatment did not reduce glucose tolerance in our model. The expression of functional thermogenic protein uncoupling protein 1 (UCP1) was increased in brown adipose tissue (BAT) of the olanzapine group. Additionally, olanzapine treatment also reduced adipose inflammation in white adipose tissue (WAT). The transcription factor sterol regulatory element-binding protein (SREBP)-1c, a key early regulator of lipogenesis, was downregulated following olanzapine treatment. The expression of genes related to the triglycerides synthesis apparatus in the liver was upregulated in the olanzapine group. Olanzapine treatment induced genes involved in PPAR-α signaling and mitochondrial fatty acid oxidation in response to increased ATGL-mediated lipolysis in the liver. Conclusion: Together, our findings suggest a complicated link between olanzapine therapy and metabolic disturbance and may garner interest in assessing the action of antipsychotic-induced metabolic disturbances.

Circulating Fatty Objects and Their Preferential Presence in Pancreatic Cancer Patient Blood Samples.

Human cancers are often complicated with increased incidences of blood vessel occlusion, which are mostly insensitive to anticoagulation therapy. We searched for causal factors of cancer-associated embolism. A total of 2,017 blood samples was examined for visible abnormalities. Examined were peripheral blood samples from cancer patients who were about to undergo surgical treatment for genitourinary, breast, gastrointestinal or abdominal tumors. Samples from ambulatory patients being treated for recurrent or castration-resistant prostate cancers were included in the study. The lipid-rich nature was studied with lipophilic stains and lipid panel analysis, while surface membrane was assessed with specific staining and antibody detection. We identified a new entity, lipid droplet-like objects or circulating fatty objects (CFOs), visible in the blood samples of many cancer patients, with the potential of causing embolism. CFOs were defined as lipid-rich objects with a membrane, capable of gaining in volume through interaction with peripheral blood mononuclear cells in ex vivo culture. Blood samples from pancreatic cancer patients were found to have the highest CFO incidence and largest CFO numbers. Most noticeably, CFOs from many pancreatic cancer samples presented as large clusters entangled in insoluble fiber networks, suggestive of intravascular clotting. This study identifies CFO as an abnormal entity in cancer patient blood, and a contributory factor to intravascular embolism during cancer development and progression.

ONECUT2 is a targetable master regulator of lethal prostate cancer that suppresses the androgen axis.

Treatment of prostate cancer (PC) by androgen suppression promotes the emergence of aggressive variants that are androgen receptor (AR) independent. Here we identify the transcription factor ONECUT2 (OC2) as a master regulator of AR networks in metastatic castration-resistant prostate cancer (mCRPC). OC2 acts as a survival factor in mCRPC models, suppresses the AR transcriptional program by direct regulation of AR target genes and the AR licensing factor FOXA1, and activates genes associated with neural differentiation and progression to lethal disease. OC2 appears active in a substantial subset of human prostate adenocarcinoma and neuroendocrine tumors. Inhibition of OC2 by a newly identified small molecule suppresses metastasis in mice. These findings suggest that OC2 displaces AR-dependent growth and survival mechanisms in many cases where AR remains expressed, but where its activity is bypassed. OC2 is also a potential drug target in the metastatic phase of aggressive PC.

Emerin Deregulation Links Nuclear Shape Instability to Metastatic Potential.

Abnormalities in nuclear shape are a well-known feature of cancer, but their contribution to malignant progression remains poorly understood. Here, we show that depletion of the cytoskeletal regulator, Diaphanous-related formin 3 (DIAPH3), or the nuclear membrane-associated proteins, lamin A/C, in prostate and breast cancer cells, induces nuclear shape instability, with a corresponding gain in malignant properties, including secretion of extracellular vesicles that contain genomic material. This transformation is characterized by a reduction and/or mislocalization of the inner nuclear membrane protein, emerin. Consistent with this, depletion of emerin evokes nuclear shape instability and promotes metastasis. By visualizing emerin localization, evidence for nuclear shape instability was observed in cultured tumor cells, in experimental models of prostate cancer, in human prostate cancer tissues, and in circulating tumor cells from patients with metastatic disease. Quantitation of emerin mislocalization discriminated cancer from benign tissue and correlated with disease progression in a prostate cancer cohort. Taken together, these results identify emerin as a mediator of nuclear shape stability in cancer and show that destabilization of emerin can promote metastasis.Significance: This study identifies a novel mechanism integrating the control of nuclear structure with the metastatic phenotype, and our inclusion of two types of human specimens (cancer tissues and circulating tumor cells) demonstrates direct relevance to human cancer.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/21/6086/F1.large.jpg Cancer Res; 78(21); 6086-97. ©2018 AACR.

Whole-genome and Transcriptome Sequencing of Prostate Cancer Identify New Genetic Alterations Driving Disease Progression.

BACKGROUND: Global disparities in prostate cancer (PCa) incidence highlight the urgent need to identify genomic abnormalities in prostate tumors in different ethnic populations including Asian men. OBJECTIVE: To systematically explore the genomic complexity and define disease-driven genetic alterations in PCa. DESIGN, SETTING, AND PARTICIPANTS: The study sequenced whole-genome and transcriptome of tumor-benign paired tissues from 65 treatment-naive Chinese PCa patients. Subsequent targeted deep sequencing of 293 PCa-relevant genes was performed in another cohort of 145 prostate tumors. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The genomic alteration landscape in PCa was analyzed using an integrated computational pipeline. Relationships with PCa progression and survival were analyzed using nonparametric test, log-rank, and multivariable Cox regression analyses. RESULTS AND LIMITATIONS: We demonstrated an association of high frequency of CHD1 deletion with a low rate of TMPRSS2-ERG fusion and relatively high percentage of mutations in androgen receptor upstream activator genes in Chinese patients. We identified five putative clustered deleted tumor suppressor genes and provided experimental and clinical evidence that PCDH9, deleted/loss in approximately 23% of tumors, functions as a novel tumor suppressor gene with prognostic potential in PCa. Furthermore, axon guidance pathway genes were frequently deregulated, including gain/amplification of PLXNA1 gene in approximately 17% of tumors. Functional and clinical data analyses showed that increased expression of PLXNA1 promoted prostate tumor growth and independently predicted prostate tumor biochemical recurrence, metastasis, and poor survival in multi-institutional cohorts of patients with PCa. A limitation of this study is that other genetic alterations were not experimentally investigated. CONCLUSIONS: There are shared and salient genetic characteristics of PCa in Chinese and Caucasian men. Novel genetic alterations in PCDH9 and PLXNA1 were associated with disease progression. PATIENT SUMMARY: We reported the first large-scale and comprehensive genomic data of prostate cancer from Asian population. Identification of these genetic alterations may help advance prostate cancer diagnosis, prognosis, and treatment.

Bone Metastasis of Prostate Cancer Can Be Therapeutically Targeted at the TBX2-WNT Signaling Axis.

Identification of factors that mediate visceral and bone metastatic spread and subsequent bone remodeling events is highly relevant to successful therapeutic intervention in advanced human prostate cancer. TBX2, a T-box family transcription factor that negatively regulates cell-cycle inhibitor p21, plays critical roles during embryonic development, and recent studies have highlighted its role in cancer. Here, we report that TBX2 is overexpressed in human prostate cancer specimens and bone metastases from xenograft mouse models of human prostate cancer. Blocking endogenous TBX2 expression in PC3 and ARCaPM prostate cancer cell models using a dominant-negative construct resulted in decreased tumor cell proliferation, colony formation, and invasion in vitro Blocking endogenous TBX2 in human prostate cancer mouse xenografts decreased invasion and abrogation of bone and soft tissue metastasis. Furthermore, blocking endogenous TBX2 in prostate cancer cells dramatically reduced bone-colonizing capability through reduced tumor cell growth and bone remodeling in an intratibial mouse model. TBX2 acted in trans by promoting transcription of the canonical WNT (WNT3A) promoter. Genetically rescuing WNT3A levels in prostate cancer cells with endogenously blocked TBX2 partially restored the TBX2-induced prostate cancer metastatic capability in mice. Conversely, WNT3A-neutralizing antibodies or WNT antagonist SFRP-2 blocked TBX2-induced invasion. Our findings highlight TBX2 as a novel therapeutic target upstream of WNT3A, where WNT3A antagonists could be novel agents for the treatment of metastasis and for skeletal complications in prostate cancer patients. Cancer Res; 77(6); 1331-44. ©2017 AACR.

Folate deficiency-induced oxidative stress contributes to neuropathy in young and aged zebrafish--implication in neural tube defects and Alzheimer's diseases.

Folate is a nutrient essential for the development, function and regeneration of nervous systems. Folate deficiency has been linked to many neurological disorders including neural tube defects in fetus and Alzheimer's diseases in the elderly. However, the etiology underlying these folate deficiency-associated diseases is not completely understood. In this study, zebrafish transgenic lines with timing and duration-controllable folate deficiency were developed by ectopically overexpressing a recombinant EGFP-γ-glutamyl hydrolase (γGH). Impeded neural crest cell migration was observed in the transgenic embryos when folate deficiency was induced in early stages, leading to defective neural tube closure and hematopoiesis. Adding reduced folate or N-acetylcysteine reversed the phenotypic anomalies, supporting the causal link between the increased oxidative stress and the folate deficiency-induced abnormalities. When folate deficiency was induced in aged fish accumulation of beta-amyloid and phosphorylated Tau protein were found in the fish brain cryo-sections. Increased autophagy and accumulation of acidic autolysosome were apparent in folate deficient neuroblastoma cells, which were reversed by reduced folate or N-acetylcysteine supplementation. Decreased expression of cathepsin B, a lysosomal protease, was also observed in cells and tissue with folate deficiency. We concluded that folate deficiency-induced oxidative stress contributed to the folate deficiency-associated neuropathogenesis in both early and late stages of life.

Detection of live circulating tumor cells by a class of near-infrared heptamethine carbocyanine dyes in patients with localized and metastatic prostate cancer.

Tumor cells are inherently heterogeneous and often exhibit diminished adhesion, resulting in the shedding of tumor cells into the circulation to form circulating tumor cells (CTCs). A fraction of these are live CTCs with potential of metastatic colonization whereas others are at various stages of apoptosis making them likely to be less relevant to understanding the disease. Isolation and characterization of live CTCs may augment information yielded by standard enumeration to help physicians to more accurately establish diagnosis, choose therapy, monitor response, and provide prognosis. We previously reported on a group of near-infrared (NIR) heptamethine carbocyanine dyes that are specifically and actively transported into live cancer cells. In this study, this viable tumor cell-specific behavior was utilized to detect live CTCs in prostate cancer patients. Peripheral blood mononuclear cells (PBMCs) from 40 patients with localized prostate cancer together with 5 patients with metastatic disease were stained with IR-783, the prototype heptamethine cyanine dye. Stained cells were subjected to flow cytometric analysis to identify live (NIR(+)) CTCs from the pool of total CTCs, which were identified by EpCAM staining. In patients with localized tumor, live CTC counts corresponded with total CTC numbers. Higher live CTC counts were seen in patients with larger tumors and those with more aggressive pathologic features including positive margins and/or lymph node invasion. Even higher CTC numbers (live and total) were detected in patients with metastatic disease. Live CTC counts declined when patients were receiving effective treatments, and conversely the counts tended to rise at the time of disease progression. Our study demonstrates the feasibility of applying of this staining technique to identify live CTCs, creating an opportunity for further molecular interrogation of a more biologically relevant CTC population.

Inhibition of ß2-microglobulin/hemochromatosis enhances radiation sensitivity by induction of iron overload in prostate cancer cells.

BACKGROUND: Bone metastasis is the most lethal form of several cancers. The ß2-microglobulin (ß2-M)/hemochromatosis (HFE) complex plays an important role in cancer development and bone metastasis. We demonstrated previously that overexpression of ß2-M in prostate, breast, lung and renal cancer leads to increased bone metastasis in mouse models. Therefore, we hypothesized that ß2-M is a rational target to treat prostate cancer bone metastasis. RESULTS: In this study, we demonstrate the role of ß2-M and its binding partner, HFE, in modulating radiation sensitivity and chemo-sensitivity of prostate cancer. By genetic deletion of ß2-M or HFE or using an anti-ß2-M antibody (Ab), we demonstrate that prostate cancer cells are sensitive to radiation in vitro and in vivo. Inhibition of ß2-M or HFE sensitized prostate cancer cells to radiation by increasing iron and reactive oxygen species and decreasing DNA repair and stress response proteins. Using xenograft mouse model, we demonstrate that anti-ß2-M Ab sensitizes prostate cancer cells to radiation treatment. Additionally, anti-ß2-M Ab was able to prevent tumor growth in an immunocompetent spontaneous prostate cancer mouse model. Since bone metastasis is lethal, we used a bone xenograft model to test the ability of anti-ß2-M Ab and radiation to block tumor growth in the bone. Combination treatment significantly prevented tumor growth in the bone xenograft model by inhibiting ß2-M and inducing iron overload. In addition to radiation sensitive effects, inhibition of ß2-M sensitized prostate cancer cells to chemotherapeutic agents. CONCLUSION: Since prostate cancer bone metastatic patients have high ß2-M in the tumor tissue and in the secreted form, targeting ß2-M with anti-ß2-M Ab is a promising therapeutic agent. Additionally, inhibition of ß2-M sensitizes cancer cells to clinically used therapies such as radiation by inducing iron overload and decreasing DNA repair enzymes.

Optical imaging of kidney cancer with novel near infrared heptamethine carbocyanine fluorescent dyes.

PURPOSE: We assessed the application of near infrared heptamethine carbocyanine dyes, including IR-783 and the synthetic analogue MHI-148, as optical imaging agents for the rapid detection of human kidney cancer. MATERIALS AND METHODS: The uptake, retention and subcellular localization of these organic dyes were investigated in cultured kidney cancer cells. Tumor specificity of dye uptake and retention was evaluated by whole body imaging of mice bearing human kidney cancer xenografts or freshly harvested clinical kidney cancer specimens. In addition, dye accumulation at the tissue and cellular levels was confirmed by ex vivo studies with results confirmed by fluorescence imaging of frozen tissue sections. Peripheral blood spiked with kidney cancer cells was stained to simulate the detection of circulating tumor cells. RESULTS: Preferential uptake and retention of carbocyanine near infrared dyes was observed in cultured human kidney cancer cells, human kidney cancer cell spiked whole blood, human kidney cancer xenografts and freshly harvested human kidney cancer tissues compared to normal kidney epithelial cells and normal host organs. CONCLUSIONS: We describe a new class of near infrared heptamethine carbocyanine dyes that show potential for detecting kidney cancer cells in circulating blood and kidney cancer cells in clinical specimens. Near infrared carbocyanine dyes can be further developed as dual modality agents for deep tissue imaging of localized and disseminated kidney cancer in patients.

In-office treatment for dentin hypersensitivity: a systematic review and network meta-analysis.

AIM: Dentin hypersensitivity, caused by the exposure and patency of dentinal tubules, can affect patients' quality of life. The aim of this study was to undertake a systematic review and a network meta-analysis, comparing the effectiveness in resolving dentin hypersensitivity among different in-office desensitizing treatments. MATERIALS AND METHODS: A literature search was performed with electronic databases and by hand until December 2011. The included trials were divided into six treatment groups as placebo, physical occlusion, chemical occlusion, nerve desensitization, laser therapy and combined treatments. The treatment effects between groups were estimated with standardized mean differences by using a Bayesian network meta-analysis. RESULTS: Forty studies were included. The standardized mean difference between placebo and physical occlusion was -2.57 [95% credible interval (CI): -4.24 to -0.94]; placebo versus chemical occlusion was -2.33 (95% CI: -3.65 to -1.04); placebo versus nerve desensitization was -1.72 (95% CI: -4.00 to 0.52); placebo versus laser therapy was -2.81 (95% CI: -4.41 to -1.24); placebo versus combined treatment was -3.47 (95% CI: -5.99 to -0.96). The comparisons of the five active treatments showed no significant differences. CONCLUSIONS: The results from network meta-analysis showed that most active treatment options had significantly better treatment outcome than placebo.

Pre-existing Fas ligand (FasL) in cancer cells elicits tumor-specific protective immunity, but delayed induction of FasL expression after inoculation facilitates tumor formation.

Overexpression of Fas ligand (FasL) in cancer cells elicits potential antitumor effects via recruitment of neutrophils. Conversely, FasL-expressing tumors may counterattack tumor-infiltrating lymphocytes by delivering apoptotic death signals via Fas/FasL interactions, which may lead to tumor escape. In order to distinguish the role of FasL in antitumor activity and tumor progression, Lewis lung carcinoma cells (LLC-1) were used to establish the cell line LLC-FasL, in which FasL expression was repressed by doxycycline (Dox) treatment and induced in the absence of Dox. LLC-FasL cells promote tumor regression when expressing FasL, whereas tumor outgrowth is observed by depletion of FasL expression. To investigate whether initial expression of FasL during tumor formation is critical for FasL-mediated tumor regression, Dox-treated LLC-FasL cells were inoculated into Dox-treated mice, but Dox treatment was stopped 5 days after inoculation. When low cell numbers were inoculated, we observed 80% survival and no tumor formation, whereas no mice survived inoculation with high cell numbers, despite the delayed induction of FasL by Dox withdrawal. The inoculation of a high density of cells may establish a favorable tumor microenvironment before the expression of FasL. Our findings demonstrate that FasL may elicit antitumor activity when it is initially present on injected cancer cells and thus can act prior to tumor microenvironment formation. Furthermore, a well-established tumor microenvironment abrogates FasL-mediated antitumor activity.

Sabutoclax, a Mcl-1 antagonist, inhibits tumorigenesis in transgenic mouse and human xenograft models of prostate cancer.

Resistance to available therapeutic agents has been a common problem thwarting progress in treatment of castrate-resistant and metastatic prostate cancer (PCa). Overexpression of the Bcl-2 family members, including Mcl-1, in PCa cells is known to inhibit intracellular mitochondrial-dependent apoptosis. Here we report the development of a novel transgenic mouse model that spontaneously develops prostatic intraepithelial neoplasia and adenocarcinoma by the inducible, conditional knockout of transforming growth factor ß receptor type II in stromal fibroblastic cells (Tgfbr2(ColTKO)). The Tgfbr2(ColTKO) prostate epithelia demonstrated down-regulation of luminal and basal differentiation markers, as well as Pten expression and up-regulation of Mcl-1. However, unlike in men, Tgfbr2(ColTKO) prostates exhibited no regression acutely after castration. The administration of Sabutoclax (BI-97C1), a pan-active Bcl-2 protein family antagonist mediated apoptosis in castrate-resistant PCa cells of Tgfbr2(ColTKO) mice and human subcutaneous, orthotopic, and intratibial xenograft PCa models. Interestingly, Sabutoclax had little apoptotic effect on benign prostate tissue in Tgfbr2(ColTKO) and wild-type mice. Sabutoclax was able to block c-Met activation, a critical axis in PCa metastatic progression. Further, Sabutoclax synergistically sensitized PC-3 cells to the cytotoxic effects of docetaxel (Taxotere). Together, these data suggest that Sabutoclax inhibits castrate-resistant PCa alone at the primary and bone metastatic site as well as support sensitivity to docetaxel treatment.

Spontaneous cancer-stromal cell fusion as a mechanism of prostate cancer androgen-independent progression.

We have previously shown that human prostate cancer cells are capable of acquiring malignant attributes through interaction with stromal cells in the tumor microenvironment, while the interacting stromal cells can also become affected with both phenotypic and genotypic alterations. This study used a co-culture model to investigate the mechanism underlying the co-evolution of cancer and stromal cells. Red fluorescent androgen-dependent LNCaP prostate cancer cells were cultured with a matched pair of normal and cancer-associated prostate myofibroblast cells to simulate cancer-stromal interaction, and cellular changes in the co-culture were documented by tracking the red fluorescence. We found frequent spontaneous fusions between cancer and stromal cells throughout the co-culture. In colony formation assays assessing the fate of the hybrid cells, most of the cancer-stromal fusion hybrids remained growth-arrested and eventually perished. However, some of the hybrids survived to form colonies from the co-culture with cancer-associated stromal cells. These derivative clones showed genomic alterations together with androgen-independent phenotype. The results from this study reveal that prostate cancer cells are fusogenic, and cancer-stromal interaction can lead to spontaneous fusion between the two cell types. While a cancer-stromal fusion strategy may allow the stromal compartment to annihilate invading cancer cells, certain cancer-stromal hybrids with increased survival capability may escape annihilation to form a derivative cancer cell population with an altered genotype and increased malignancy. Cancer-stromal fusion thus lays a foundation for an incessant co-evolution between cancer and the cancer-associated stromal cells in the tumor microenvironment.

Beta2-microglobulin signaling blockade inhibited androgen receptor axis and caused apoptosis in human prostate cancer cells.

PURPOSE: beta2-Microglobulin (beta2M) has been shown to promote osteomimicry and the proliferation of human prostate cancer cells. The objective of this study is to determine the mechanism by which targeting beta2M using anti-beta2M antibody inhibited growth and induced apoptosis in prostate cancer cells. EXPERIMENTAL DESIGN: Polyclonal and monoclonal beta2M antibodies were used to interrupt beta2M signaling in human prostate cancer cell lines and the growth of prostate tumors in mice. The effects of the beta2M antibody on a survival factor, androgen receptor (AR), and its target gene, prostate-specific antigen (PSA) expression, were investigated in cultured cells and in tumor xenografts. RESULTS: The beta2M antibody inhibited growth and promoted apoptosis in both AR-positive and PSA-positive, and AR-negative and PSA-negative, prostate cancer cells via the down-regulation of the AR in AR-positive prostate cancer cells and directly caused apoptosis in AR-negative prostate cancer cells in vitro and in tumor xenografts. The beta2M antibody had no effect on AR expression or the growth of normal prostate cells. CONCLUSIONS: beta2M downstream signaling regulates AR and PSA expression directly in AR-positive prostate cancer cells. In both AR-positive and AR-negative prostate cancer cells, interrupting beta2M signaling with the beta2M antibody inhibited cancer cell growth and induced its apoptosis. The beta2M antibody is a novel and promising therapeutic agent for the treatment of human prostate cancers.