Bax suppresses tumorigenesis and stimulates apoptosis in vivo

The protein p53 is a key tumour-suppressor, as evidenced by its frequent inactivation in human cancers. Animal models have indicated that attenuation of p53-dependent cell death (apoptosis) can contribute to both the initiation and progression of cancer, but the molecular mechanisms are unknown. Although p53-mediated transcriptional activation is one possible explanation, none of the known p53-responsive genes has been shown to function in p53-dependent apoptosis. Here we test the role of the death-promoting gene bax in a transgenic mouse brain tumour, a model in which p53-mediated apoptosis attenuates tumour growth. Inactivation of p53 causes a dramatic acceleration of tumour growth owing to a reduction in apoptosis of over ninety per cent. We show that p53-dependent expression of bax is induced in slow-growing apoptotic tumours. Moreover, tumour growth is accelerated and apoptosis drops by fifty per cent in Bax-deficient mice, indicating that it is required for a full p53-mediated response. To our knowledge this is the first demonstration that Bax acts as a tumour suppressor, and our findings indicate that Bax could be a component of the p53-mediated apoptotic response in this system.

ApoE attenuates unresolvable inflammation by complex formation with activated C1q

ApoE has been implicated in Alzheimer´s disease, atherosclerosis, and other unresolvable inflammatory conditions but a common mechanism of action remains elusive. We found in ApoE-deficient mice that oxidized lipids activated the classical complement cascade (CCC) resulting in leukocyte infiltration of the choroid plexus (ChP). All human ApoE isoforms attenuated CCC activity via high-affinity binding to the activated CCC-initiating C1q protein (K_D~140-580 pM) in vitro; and C1q-ApoE complexes emerged as markers for ongoing complement activity of diseased ChPs, Aβ plaques, and atherosclerosis in vivo. C1q-ApoE complexes in human ChPs, Aβ plaques, and arteries correlated with cognitive decline and atherosclerosis, respectively. Treatment with siRNA against C5 which is formed by all complement pathways, attenuated murine ChP inflammation, Aβ-associated microglia accumulation, and atherosclerosis. Thus, ApoE is a direct checkpoint inhibitor of unresolvable inflammation and reducing C5 attenuates disease burden.

Slow aging during insect reproductive diapause: why butterflies, grasshoppers and flies are like worms

Diapause is a state of arrested development accompanied by physiology for somatic persistence. Diapause is common in many invertebrates and is familiar to biogerontology in the context of Caenorhabditis elegans dauer. Among insects, diapause may occur in embryos, larvae, pupae or adults. At the adult stage, reproductive diapause arrests development of oogenesis, vitellogenesis, accessory gland activity, and mating behavior. Reproductive diapause has been well studied in monarch butterflies, several grasshoppers, and several Diptera, including Drosophila and Phormia. In monarchs and in grasshoppers, reproductive diapause physiology has been experimentally induced by the surgical removal of the corpora allata, the source of adult juvenile hormone; allatectomy in each case was found to double adult longevity. Among Drosophila, the endemic D. triauraria of Japan, and D. littoralis of Finland over-winter as adults in reproductive diapause. How D. melanogaster winter is poorly understood, but reproductive diapause can be cued by cool temperature. In laboratory studies, the mortality rates of post-diapause D. melanogaster are similar to rates of newly enclosed, young flies. This implies that senescence during diapause is slow or negligible. Slow aging during the diapause period may involve elevated somatic stress resistance as well as reallocation of resources to somatic maintenance. Reproductive diapause in Drosophila is proximally controlled by down regulation of juvenile hormone, a phenotype that is also produced by mutants of the insulin-like receptor InR, homologue of C. elegans daf-2. We propose neuroendocrine control of reproductive diapause in D. melanogaster that includes phenotypic plasticity for rates of senescence.

Artery Tertiary Lymphoid Organs Control Aorta Immunity and Protect against Atherosclerosis via Vascular Smooth Muscle Cell Lymphotoxin β Receptors

Tertiary lymphoid organs (TLOs) emerge during nonresolving peripheral inflammation, but their impact on disease progression remains unknown. We have found in aged Apoe^−/− mice that artery TLOs (ATLOs) controlled highly territorialized aorta T cell responses. ATLOs promoted T cell recruitment, primed CD4⁺ T cells, generated CD4⁺, CD8⁺, T regulatory (Treg) effector and central memory cells, converted naive CD4⁺ T cells into induced Treg cells, and presented antigen by an unusual set of dendritic cells and B cells. Meanwhile, vascular smooth muscle cell lymphotoxin β receptors (VSMC-LTβRs) protected against atherosclerosis by maintaining structure, cellularity, and size of ATLOs though VSMC-LTβRs did not affect secondary lymphoid organs: Atherosclerosis was markedly exacerbated in Apoe^−/−Ltbr^−/− and to a similar extent in aged Apoe^−/−Ltbr^fl/flTagln-cre mice. These data support the conclusion that the immune system employs ATLOs to organize aorta T cell homeostasis during aging and that VSMC-LTβRs participate in atherosclerosis protection via ATLOs.

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Artery tertiary lymphoid organs control atherosclerosis T cell immunity

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Artery tertiary lymphoid organs generate effector memory T cells

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Artery tertiary lymphoid organs convert naive CD4⁺ T cells into induced Treg cells

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Artery tertiary lymphoid organs protect from atherosclerosis

Key roles for E2F1 in signaling p53-dependent apoptosis and in cell division within developing tumors

Apoptosis induced by the p53 tumor suppressor can attenuate cancer growth in preclinical animal models. Inactivation of the pRb proteins in mouse brain epithelium by the T121 oncogene induces aberrant proliferation and p53-dependent apoptosis. p53 inactivation causes aggressive tumor growth due to an 85% reduction in apoptosis. Here, we show that E2F1 signals p53-dependent apoptosis since E2F1 deficiency causes an 80% apoptosis reduction. E2F1 acts upstream of p53 since transcriptional activation of p53 target genes is also impaired. Yet, E2F1 deficiency does not accelerate tumor growth. Unlike normal cells, tumor cell proliferation is impaired without E2F1, counterbalancing the effect of apoptosis reduction. These studies may explain the apparent paradox that E2F1 can act as both an oncogene and a tumor suppressor in experimental systems.

Prostate cancer in Asia: A collaborative report

The incidence of prostate cancer (PCa) within Asian population used to be much lower than in the Western population; however, in recent years the incidence and mortality rate of PCa in some Asian countries have grown rapidly. This collaborative report summarized the latest epidemiology information, risk factors, and racial differences in PCa diagnosis, current status and new trends in surgery management and novel agents for castration-resistant prostate cancer. We believe such information would be helpful in clinical decision making for urologists and oncologists, health-care ministries and medical researchers.

Hepatocyte nuclear factor 4alpha attenuates hepatic fibrosis in rats

BACKGROUND AND AIMS

Hepatocyte nuclear factor 4alpha (HNF4alpha) is a central transcriptional regulator of hepatocyte differentiation and function. The aim of this study was to evaluate the effect of HNF4alpha on attenuation of hepatic fibrosis.

METHODS

The adenoviruses carrying HNF4alpha gene or containing siRNA targeting HNF4alpha were injected through tail vein on two distinct hepatic fibrosis models either induced by dimethylnitrosamine or by bile duct ligation in rats. Moreover, HNF4alpha, epithelial-mesenchymal transition (EMT)-related and fibrotic markers in hepatocytes, hepatic stellate cells (HSCs) and liver tissues were detected by real time PCR, immunofluorescence or immunohistochemistry.

RESULTS

We demonstrated that decreased expression of HNF4alpha and epithelial markers accompanied by enhanced expression of mesenchymal markers occurred in fibrotic liver. More importantly, forced expression of HNF4alpha remarkably alleviated hepatic fibrosis and improved liver function with suppression of EMT in both fibrosis models. In contrast, downregulation of HNF4alpha by siRNA aggravated hepatic fibrosis and decreased the expression of E-cadherin in association with the enhanced expression of vimentin and fibroblast-specific protein-1. In vitro study revealed that HNF4alpha could suppress the EMT process of hepatocytes induced by transforming growth factor-beta1 and increase the expression of liver-specific genes. A similar phenomenon of the EMT process was observed during the activation of HSCs, which was abrogated by HNF4alpha. Additionally, HNF4alpha deactivated the myofibroblasts through inducing the mesenchymal-to-epithelial transition and inhibited their proliferation.

CONCLUSIONS

Our study suggests that HNF4alpha is critical for hepatic fibrogenesis and upregulation of HNF4alpha might present as an ideal option for the treatment of hepatic fibrosis.

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.

Neuroimmune cardiovascular interfaces control atherosclerosis

Atherosclerotic plaques develop in the inner intimal layer of arteries and can cause heart attacks and strokes¹. As plaques lack innervation, the effects of neuronal control on atherosclerosis remain unclear. However, the immune system responds to plaques by forming leukocyte infiltrates in the outer connective tissue coat of arteries (the adventitia)^2-6. Here, because the peripheral nervous system uses the adventitia as its principal conduit to reach distant targets^7-9, we postulated that the peripheral nervous system may directly interact with diseased arteries. Unexpectedly, widespread neuroimmune cardiovascular interfaces (NICIs) arose in mouse and human atherosclerosis-diseased adventitia segments showed expanded axon networks, including growth cones at axon endings near immune cells and media smooth muscle cells. Mouse NICIs established a structural artery-brain circuit (ABC): abdominal adventitia nociceptive afferents^10-14 entered the central nervous system through spinal cord T₆-T₁₃ dorsal root ganglia and were traced to higher brain regions, including the parabrachial and central amygdala neurons; and sympathetic efferent neurons projected from medullary and hypothalamic neurons to the adventitia through spinal intermediolateral neurons and both coeliac and sympathetic chain ganglia. Moreover, ABC peripheral nervous system components were activated: splenic sympathetic and coeliac vagus nerve activities increased in parallel to disease progression, whereas coeliac ganglionectomy led to the disintegration of adventitial NICIs, reduced disease progression and enhanced plaque stability. Thus, the peripheral nervous system uses NICIs to assemble a structural ABC, and therapeutic intervention in the ABC attenuates atherosclerosis.

Circulating miR-497 and miR-663b in plasma are potential novel biomarkers for bladder cancer

MicroRNAs (miRNAs), abundant and highly stable in the plasma, have been widely reported. This greatly pursued us to investigate whether plasma miRNAs could be considered as powerful biomarkers for diagnosing bladder cancer (BC). We performed a plasma miRNAs profile with the TaqMan Low Density Array, and a two-phase validation to detect the candidate miRNAs expression by quantitative PCR. The receiver operating characteristic curve (ROC) and the area under curve (AUC) were used to evaluate diagnostic accuracy. A total of eight plasma miRNAs abnormally expressed between BC patients and healthy controls in microarray analysis (i.e., elevated miRNAs for miR-505, miR-363 and miR-663b, and decreased for miR-99a, miR-194, miR-100, miR-497 and miR-1 in BC plasma). In further independent cohorts, miR-497 and miR-663b with significantly differential expression were confirmed. Moreover, the AUC, sensitivity and specificity were raised to 0.711 (95% CI = 0.641-0.780), 69.7% and 69.6%, respectively, when miR-497 and miR-663b were integrated. This is the first study systematically exploring the existence of specific plasma miRNAs as early diagnostic biomarkers for BC in Chinese population; and these findings supported that plasma miR-497 and miR-663b could be promising novel circulating biomarkers in clinical detection of BC.

Identification of novel piRNAs in bladder cancer

PIWI-interacting RNAs (piRNAs) are a newly identified class of small non-coding RNAs that can play important roles in germline development and carcinogenesis. In this study, piRNA microarrays were used to investigate global piRNA expression in three bladder cancer tissues and their adjacent normal tissues. Using the 3' untranslated region (UTR) sequence complementarily method, we predicted the target gene of piRNA. Our results showed that the expression levels of 106 piRNAs were up-regulated and 91 were down-regulated in bladder cancer tissues, among which the fold-change of down-regulated piRNA DQ594040 associated with bladder cancer (piRABC) was the highest piRNA. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to confirm piRABC expression in paired bladder cancer tissues and their adjacent normal tissues (n = 25). Over-expression of piRABC can inhibit bladder cancer cell proliferation, colony formation, and promote cell apoptosis (all P < 0.05). Luciferase reporter gene assays indicated that piRABC could increase the luciferase activity of TNFSF4. Western blotting analyses and ELISA assays also confirmed that the expression of TNFSF4 protein was up-regulated in control subjects compared with bladder cancer subjects. In conclusion, piRABC plays a crucial role in the development of bladder cancer.

Type-2 innate lymphoid cells control the development of atherosclerosis in mice

Type-2 innate lymphoid cells (ILC2) are a prominent source of type II cytokines and are found constitutively at mucosal surfaces and in visceral adipose tissue. Despite their role in limiting obesity, how ILC2s respond to high fat feeding is poorly understood, and their direct influence on the development of atherosclerosis has not been explored. Here, we show that ILC2 are present in para-aortic adipose tissue and lymph nodes and display an inflammatory-like phenotype atypical of adipose resident ILC2. High fat feeding alters both the number of ILC2 and their type II cytokine production. Selective genetic ablation of ILC2 in Ldlr^−/− mice accelerates the development of atherosclerosis, which is prevented by reconstitution with wild type but not Il5^−/− or Il13^−/− ILC2. We conclude that ILC2 represent a major innate cell source of IL-5 and IL-13 required for mounting atheroprotective immunity, which can be altered by high fat diet.

Type-2 innate lymphoid cells (ILC2) affect adipose tissue metabolism and function. Here the authors show that the ILC2 are present in para-aortic adipose tissue and represent a major source of IL-5 and IL-13 required for mounting atheroprotective immunity, which can be altered by high fat diet.

Effect of Bacillus subtilis CGMCC 1.1086 on the growth performance and intestinal microbiota of broilers

AIMS

Probiotics have been proved to be the most preferred and effective alternative to antibiotics as growth promoter and pathogens inhibitor in poultry industry. In this study Bacillus subtilis CGMCC 1.1086 as a probiotic bacterium was administered in diet and its effects on both the growth performance and the caecal microbiota of broilers were evaluated.

METHODS AND RESULTS

A total of 240 male Arbor Acres (AA) broilers were randomly allocated into two treatment groups of basal diet without any addition of probiotics and basal diet containing B. subtilis CGMCC 1.1086. The body weight of broilers was measured individually at 32, 39 and 46 days of bird age. Furthermore, MiSeq high-throughput sequencing analysis of 16S rRNA was used to investigate the bacterial community structure in the caeca of broilers. The results indicated that broilers receiving diet supplemented with B. subtilis CGMCC 1.1086 showed 27·7% higher daily weight gain than those of control during 2 weeks. The feed conversion ratio (FCR) of B. subtilis CGMCC 1.1086 group was also improved by 10·3%. In the caeca of broilers fed with B. subtilis CGMCC 1.1086, the relative abundance of Alistipes, Odoribacter, Ruminococcus, Blautia and Desulfovibrio were higher, while the potential pathogens such as Staphylococcus and Escherichia-Shigella were lower than those of control.

CONCLUSIONS

The probiotic B. subtilis CGMCC 1.1086 can effectively improve the growth performance and FCR of broilers via the beneficial modulation of caecal microbiota.

SIGNIFICANCE AND IMPACT OF THE STUDY

The effect of B. subtilis on growth performance of broilers was evaluated and the relationship between growth and caecal microbiota was revealed. The results of this study help to promote application of probiotics in poultry industry.

Artery Tertiary Lymphoid Organs Contribute to Innate and Adaptive Immune Responses in Advanced Mouse Atherosclerosis

Tertiary lymphoid organs emerge in tissues in response to nonresolving inflammation. Recent research characterized artery tertiary lymphoid organs in the aorta adventitia of aged apolipoprotein E–deficient mice. The atherosclerosis-associated lymphocyte aggregates are organized into distinct compartments, including separate T-cell areas harboring conventional, monocyte-derived, lymphoid, and plasmacytoid dendritic cells, as well as activated T-cell effectors and memory cells; B-cell follicles containing follicular dendritic cells in activated germinal centers; and peripheral niches of plasma cells. Artery tertiary lymphoid organs show marked neoangiogenesis, aberrant lymphangiogenesis, and extensive induction of high endothelial venules. Moreover, newly formed lymph node–like conduits connect the external lamina with high endothelial venules in T-cell areas and also extend into germinal centers. Mouse artery tertiary lymphoid organs recruit large numbers of naïve T cells and harbor lymphocyte subsets with opposing activities, including CD4 + and CD8 + effector and memory T cells, natural and induced CD4 + regulatory T cells, and memory B cells at different stages of differentiation. These data suggest that artery tertiary lymphoid organs participate in primary immune responses and organize T- and B-cell autoimmune responses in advanced atherosclerosis. In this review, we discuss the novel concept that pro- and antiatherogenic immune responses toward unknown arterial wall–derived autoantigens may be organized by artery tertiary lymphoid organs and that disruption of the balance between pro- and antiatherogenic immune cell subsets may trigger clinically overt atherosclerosis.

Precise segmental renal artery clamping under the guidance of dual-source computed tomography angiography during laparoscopic partial nephrectomy

BACKGROUND

Minimizing warm ischemic (WI) injury is one technical focus of partial nephrectomy (PN). Inducing regional ischemia in the tumor area by clamping segmental renal arteries has become an alternative method to decrease WI injury.

OBJECTIVE

To study the technical feasibility of precise segmental artery clamping under the guidance of dual-source computed tomography (DSCT) angiography during laparoscopic partial nephrectomy (LPN) and to analyze the factors affecting surgical outcomes.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective analysis of 125 patients with unilateral kidney tumor treated from December 2009 to November 2011 with a mean follow-up of 18 mo.

INTERVENTION

All patients received retroperitoneal LPN with the feeding segmental arteries precisely clamped. Most of the target branches were dissected close to the hilar parenchyma. The tumor was excised after precise clamping and renorrhaphy was performed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Univariable and multivariable logistic regression analyses were performed for categorical variables, and continuous variables were analyzed by linear regression.

RESULTS AND LIMITATIONS

The target branches were isolated and clamped successfully in all patients without clamping the main renal artery. Median estimated blood loss (EBL) was 200 ml, and nine patients received blood transfusion. The accuracy of feeding artery orientation by DSCT angiography reached 93.6%. Tumor size, location, and growth pattern independently influenced the number of clamped branches. The number of clamped branches was significantly associated with postoperative renal function and EBL. Limitations of this study include its retrospective nature and that data are from a single-surgeon series.

CONCLUSIONS

The precise segmental artery clamping technique under the guidance of DSCT angiography is feasible and efficient to excise the tumor and to protect the normal parenchyma. The number of clamped branches is associated with tumor characteristics and can predict EBL and loss of renal function.

Artery Tertiary Lymphoid Organs Control Multilayered Territorialized Atherosclerosis B-Cell Responses in Aged ApoE-/- Mice

Supplemental Digital Content is available in the text.

Objective—

Explore aorta B-cell immunity in aged apolipoprotein E-deficient (ApoE^−/−) mice.

Approach and Results—

Transcript maps, fluorescence-activated cell sorting, immunofluorescence analyses, cell transfers, and Ig-ELISPOT (enzyme-linked immunospot) assays showed multilayered atherosclerosis B-cell responses in artery tertiary lymphoid organs (ATLOs). Aging-associated aorta B-cell–related transcriptomes were identified, and transcript atlases revealed highly territorialized B-cell responses in ATLOs versus atherosclerotic lesions: ATLOs showed upregulation of bona fide B-cell genes, including Cd19, Ms4a1 (Cd20), Cd79a/b, and Ighm although intima plaques preferentially expressed molecules involved in non–B effector responses toward B-cell–derived mediators, that is, Fcgr3 (Cd16), Fcer1g (Cd23), and the C1q family. ATLOs promoted B-cell recruitment. ATLO B-2 B cells included naive, transitional, follicular, germinal center, switched IgG1⁺, IgA⁺, and IgE⁺ memory cells, plasmablasts, and long-lived plasma cells. ATLOs recruited large numbers of B-1 cells whose subtypes were skewed toward interleukin-10⁺ B-1b cells versus interleukin-10⁻ B-1a cells. ATLO B-1 cells and plasma cells constitutively produced IgM and IgG and a fraction of plasma cells expressed interleukin-10. Moreover, ApoE^−/− mice showed increased germinal center B cells in renal lymph nodes, IgM-producing plasma cells in the bone marrow, and higher IgM and anti–MDA-LDL (malondialdehyde-modified low-density lipoprotein) IgG serum titers.

Conclusions—

ATLOs orchestrate dichotomic, territorialized, and multilayered B-cell responses in the diseased aorta; germinal center reactions indicate generation of autoimmune B cells within the diseased arterial wall during aging.

miR-152 controls migration and invasive potential by targeting TGFα in prostate cancer cell lines

BACKGROUND

MicroRNAs (miRNAs) are a class of short non-coding RNAs that function in diverse biological processes. Aberrant miR-152 expression has been frequently reported in various malignant tumors. However, the mechanism of miR-152 in prostate cancer (PCa) remains unclear. This study aims to determine the function of miR-152 in PCa cells and identify the novel molecular targets regulated by miR-152.

METHODS

The expression levels of transforming growth factor-alpha (TGFα) were determined in three samples of PCa and adjacent non-tumorous tissues by Western blot analysis. miR-152 levels in 48 primary PCa and 15 non-malignant tissue samples were measured by qRT-PCR. The effects of forced miR-152 expression or TGFα knockdown on PCa cells were evaluated by cell migration and invasion assays, as well as Western blot analysis. Dual-luciferase reporter assay was used to identify binding sites between miR-152 and TGFα 3'-UTR.

RESULTS

TGFα was upregulated in PCa tissue samples compared with that in adjacent normal ones. miR-152 expression was significantly decreased in primary PCa samples compared with that in non-malignant samples. Patients with Gleason scores >7 exhibited lower miR-152 levels than those with lower scores. Moreover, low miR-152 expression is correlated with advanced pathological T-stages. Forced miR-152 expression or TGFα knockdown significantly reduced the migratory and invasive capabilities of PCa cells in vitro. TGFα is a direct target gene of miR-152.

CONCLUSIONS

Our findings suggest that miR-152 can act as a tumor suppressor that targets TGFα. miR-152 is a promising molecular target that inhibits PCa cell migration and invasion.

microRNA-133 inhibits cell proliferation, migration and invasion in prostate cancer cells by targeting the epidermal growth factor receptor

It has been shown that regulation of EGFR expression in prostate cancer cells is mostly at the transcriptional level. microRNA-133 (miR-133) has long been recognized as a muscle-specific miRNA which may regulate myoblast differentiation and participate in many myogenic diseases. Recently, it has been reported that miR-133 is also involved in other tumors, such as bladder cancer, esophageal cancer and may regulate cell motility in these cancer cells. In the present study, we examined the expression and effects of miR-133 in two hormone-insensitive prostate cancer cell lines. The expression of miR-133a and miR-133b were analyzed by quantitative RT-PCR. After transfection of miR-133a and miR-133b, cell viability assay, luciferase assay, western blot analysis, cell migration and invasion assay were conducted in Du145 and PC3 cells. In this study, we showed that miR‑133a and miR-133b are expressed at the detection limit in two hormone-insensitive prostate cancer cell lines, PC3 and DU145. Ectopic expression of miR-133 inhibited cell proliferation, migration and invasion in these cells. We also provide the first evidence that miR-133 may target EGFR. Our study provided the first glimpse of the functional role of miR-133 in two hormone-independent prostate cancer cell lines. These results may add to our knowledge on the molecular basis of prostate cancer progression.

Vascular Smooth Muscle Cells Contribute to Atherosclerosis Immunity

Vascular smooth muscle cells (VSMCs) constitute the major cells in the media layer of arteries, and are critical to maintain the integrity of the arterial wall. They participate in arterial wall remodeling, and play important roles in atherosclerosis throughout all stages of the disease. Studies demonstrate that VSMCs can adopt numerous phenotypes depending on inputs from endothelial cells (ECs) of the intima, resident cells of the adventitia, circulating immune cells, hormones, and plasma lipoproteins. This plasticity allows them to perform multiple tasks in physiology and disease. In this minireview, we focus on a previously underappreciated activity of VSMCs, i.e., their impact on atherosclerosis immunity via formation of artery tertiary lymphoid organs (ATLOs).

A novel germline mutation in HOXB13 is associated with prostate cancer risk in Chinese men

BACKGROUND

A rare mutation G84E in HOXB13 was recently identified to be associated with prostate cancer (PCa) in Caucasians. The goal of this study is to test association between HOXB13 genetic variants and PCa risk in Chinese men.

METHODS

All study subjects were part of the Chinese Consortium for Prostate Cancer Genetics (ChinaPCa). In the first stage, we screened for mutations by sequencing the HOXB13 coding region in 96 unrelated PCa patients. In stage 2, G84E and novel mutations found in stage 1 were genotyped in 671 PCa patients and 1,536 controls. In stage 3, mutation status in 751 additional PCa patients was imputed via haplotype.

RESULTS

The G84E mutation was not detected in this study. However, a novel mutation, G135E, was identified among 96 patients in stage 1. It was also observed twice in 575 additional PCa patients but not in 1,536 control subjects of stage 2. The frequency of G135E was significantly different between cases and controls, with a P-value of 0.027, based on Fisher's exact test. Haplotype estimation showed that G135E mutation carriers shared a unique haplotype that was not observed in other subjects. In stage 3, two more PCa patients were predicted to carry the G135E mutation.

CONCLUSIONS

We identified a novel rare mutation in the HOXB13 gene, G135E, which appears to be a founder mutation. This mutation is associated with increased PCa risk in Chinese men. Consistent with a previous report, our findings provide further evidence that rare mutations in HOXB13 contribute to PCa risk.

Tissue-specific inactivation of p53 tumor suppression in the mouse

The p53 gene is the most frequent target of structural and functional genetic mutations in human cancer. Thus, considerable effort has been devoted to mapping the functional domains of p53 with regard to their impact on tumorigenesis in vivo. Studies have shown that the carboxy-terminal domain of p53 is sufficient for transformation in vitro. To determine whether a transdominant-negative p53 protein could be used to elicit a tissue-specific p53-null effect in vivo, we tested whether a carboxy-terminal p53 fragment (amino acids 302-390) could abolish p53-dependent apoptosis in an established tumor progression model. We showed previously that loss of p53-dependent apoptosis accelerates brain tumorigenesis in a transgenic mouse model. Here, we show that the same effect can be elicited by expressing a dominant-negative p53 protein tissue specifically in the presence of wild-type p53. Transgenic mice in which pRb function has been disrupted and that coexpress a p53 carboxy-terminal dominant-negative fragment (p53DD) develop aggressive brain tumors mimicking genetic loss of p53 in this model. Inactivation of endogenous p53, which we show to be complexed with p53DD, results in a reduction in apoptosis and acceleration of tumorigenesis. These studies establish a mechanism for tissue-specific knock out of p53 function in vivo.

Artery Tertiary Lymphoid Organs: Powerhouses of Atherosclerosis Immunity

Artery tertiary lymphoid organs (ATLOs) are atherosclerosis-associated lymphoid aggregates with varying degrees of complexity ranging from small T/B-cell clusters to well-structured lymph node-like though unencapsulated lymphoid tissues. ATLOs arise in the connective tissue that surrounds diseased arteries, i.e., the adventitia. ATLOs have been identified in aged atherosclerosis-prone hyperlipidemic apolipoprotein E-deficient (ApoE-/-) mice: they are organized into distinct immune cell compartments, including separate T-cell areas, activated B-cell follicles, and plasma cell niches. Analyses of ATLO immune cell subsets indicate antigen-specific T- and B-cell immune reactions within the atherosclerotic arterial wall adventitia. Moreover, ATLOs harbor innate immune cells, including a large component of inflammatory macrophages, B-1 cells, and an aberrant set of antigen-presenting cells. There is marked neoangiogenesis, irregular lymphangiogenesis, neoformation of high endothelial venules, and de novo synthesis of lymph node-like conduits. Molecular mechanisms of ATLO formation remain to be identified though media vascular smooth muscle cells may adopt features of lymphoid tissue organizer-like cells by expressing lymphorganogenic chemokines, i.e., CXCL13 and CCL21. Although these data are consistent with the view that ATLOs participate in primary T- and B-cell responses against elusive atherosclerosis-specific autoantigens, their specific protective or disease-promoting roles remain to be identified. In this review, we discuss what is currently known about ATLOs and their potential impact on atherosclerosis and make attempts to define challenges ahead.