Estetrol/GPER/SERPINB2 transduction signaling inhibits the motility of triple-negative breast cancer cells.

BACKGROUND: Estetrol (E4) is a natural estrogen produced by the fetal liver during pregnancy. Due to its favorable safety profile, E4 was recently approved as estrogenic component of a new combined oral contraceptive. E4 is a selective ligand of estrogen receptor (ER)α and ERß, but its binding to the G Protein-Coupled Estrogen Receptor (GPER) has not been described to date. Therefore, we aimed to explore E4 action in GPER-positive Triple-Negative Breast Cancer (TNBC) cells. METHODS: The potential interaction between E4 and GPER was investigated by molecular modeling and binding assays. The whole transcriptomic modulation triggered by E4 in TNBC cells via GPER was explored through high-throughput RNA sequencing analyses. Gene and protein expression evaluations as well as migration and invasion assays allowed us to explore the involvement of the GPER-mediated induction of the plasminogen activator inhibitor type 2 (SERPINB2) in the biological responses triggered by E4 in TNBC cells. Furthermore, bioinformatics analysis was aimed at recognizing the biological significance of SERPINB2 in ER-negative breast cancer patients. RESULTS: After the molecular characterization of the E4 binding capacity to GPER, RNA-seq analysis revealed that the plasminogen activator inhibitor type 2 (SERPINB2) is one of the most up-regulated genes by E4 in a GPER-dependent manner. Worthy, we demonstrated that the GPER-mediated increase of SERPINB2 is engaged in the anti-migratory and anti-invasive effects elicited by E4 in TNBC cells. In accordance with these findings, a correlation between SERPINB2 levels and a good clinical outcome was found in ER-negative breast cancer patients. CONCLUSIONS: Overall, our results provide new insights into the mechanisms through which E4 can halt migratory and invasive features of TNBC cells.

Increased SERPINB2 potentiates 15LO1 expression via STAT6 signalling in epithelial cells in eosinophilic chronic rhinosinusitis with nasal polyps.

BACKGROUND: SERPINB2, a biomarker of Type-2 (T2) inflammatory processes, has been described in the context of asthma. Chronic rhinosinusitis with nasal polyps (CRSwNP) is also correlated with T2 inflammation and elevated 15LO1 induced by IL-4/13 in nasal epithelial cells. The aim of this study was to evaluate the expression and location of SERPINB2 in nasal epithelial cells (NECs) and determine whether SERPINB2 regulates 15LO1 and downstream T2 markers in NECs via STAT6 signalling. METHODS: SERPINB2 gene expression in bulk and single-cell RNAseq database was analysed by bioinformatics analysis. SERPINB2, 15LO1 and other T2 markers were evaluated from CRSwNP and HCs NECs. The colocalization of SERPINB2 and 15LO1 was evaluated by immunofluorescence. Fresh NECs were cultured at an air-liquid interface with or without IL-13, SERPINB2 Dicer-substrate short interfering RNAs (DsiRNAs) transfection, exogenous SERPINB2, 15-HETE recombinant protein and pSTAT6 inhibitors. 15LO1, 15-HETE and downstream T2 markers were analysed by qRT-PCR, western blot and ELISA. RESULTS: SERPINB2 expression was increased in eosinophilic nasal polyps compared with that in noneosinophilic nasal polyps and control tissues and positively correlated with 15LO1 and other downstream T2 markers. SERPINB2 was predominantly expressed by epithelial cells in NP tissue and was colocalized with 15LO1. In primary NECs in vitro, SERPINB2 expression was induced by IL-13. Knockdown or overexpression SERPINB2 decreased or enhanced expression of 15LO1 and 15-HETE in NECs, respectively, in a STAT6-dependent manner. SERPINB2 siRNA also inhibited the expression of the 15LO1 downstream genes, such as CCL26, POSTN and NOS2. STAT6 inhibition similarly decreased SERPINB2-induced 15LO1. CONCLUSIONS: SERPINB2 is increased in NP epithelial cells of eosinophilic CRSwNP (eCRSwNP) and contributes to T2 inflammation via STAT6 signalling. SERPINB2 could be considered a novel therapeutic target for eCRSwNP.

Role of different mechanisms in pro-inflammatory responses triggered by traffic-derived particulate matter in human bronchiolar epithelial cells.

BACKGROUND: Traffic-derived particles are important contributors to the adverse health effects of ambient particulate matter (PM). In Nordic countries, mineral particles from road pavement and diesel exhaust particles (DEP) are important constituents of traffic-derived PM. In the present study we compared the pro-inflammatory responses of mineral particles and DEP to PM from two road tunnels, and examined the mechanisms involved. METHODS: The pro-inflammatory potential of 100 µg/mL coarse (PM10-2.5), fine (PM2.5-0.18) and ultrafine PM (PM0.18) sampled in two road tunnels paved with different stone materials was assessed in human bronchial epithelial cells (HBEC3-KT), and compared to DEP and particles derived from the respective stone materials. Release of pro-inflammatory cytokines (CXCL8, IL-1α, IL-1ß) was measured by ELISA, while the expression of genes related to inflammation (COX2, CXCL8, IL-1α, IL-1ß, TNF-α), redox responses (HO-1) and metabolism (CYP1A1, CYP1B1, PAI-2) was determined by qPCR. The roles of the aryl hydrocarbon receptor (AhR) and reactive oxygen species (ROS) were examined by treatment with the AhR-inhibitor CH223191 and the anti-oxidant N-acetyl cysteine (NAC). RESULTS: Road tunnel PM caused time-dependent increases in expression of CXCL8, COX2, IL-1α, IL-1ß, TNF-α, COX2, PAI-2, CYP1A1, CYP1B1 and HO-1, with fine PM as more potent than coarse PM at early time-points. The stone particle samples and DEP induced lower cytokine release than all size-fractionated PM samples for one tunnel, and versus fine PM for the other tunnel. CH223191 partially reduced release and expression of IL-1α and CXCL8, and expression of COX2, for fine and coarse PM, depending on tunnel, response and time-point. Whereas expression of CYP1A1 was markedly reduced by CH223191, HO-1 expression was not affected. NAC reduced the release and expression of IL-1α and CXCL8, and COX2 expression, but augmented expression of CYP1A1 and HO-1. CONCLUSIONS: The results indicate that the pro-inflammatory responses of road tunnel PM in HBEC3-KT cells are not attributed to the mineral particles or DEP alone. The pro-inflammatory responses seem to involve AhR-dependent mechanisms, suggesting a role for organic constituents. ROS-mediated mechanisms were also involved, probably through AhR-independent pathways. DEP may be a contributor to the AhR-dependent responses, although other sources may be of importance.

A Novel Role for Plasminogen Activator Inhibitor Type-2 as a Hypochlorite-Resistant Serine Protease Inhibitor and Holdase Chaperone.

Plasminogen activator inhibitor type-2 (PAI-2), a member of the serpin family, is dramatically upregulated during pregnancy and in response to inflammation. Although PAI-2 exists in glycosylated and non-glycosylated forms in vivo, the majority of in vitro studies of PAI-2 have exclusively involved the intracellular non-glycosylated form. This study shows that exposure to inflammation-associated hypochlorite induces the oligomerisation of PAI-2 via a mechanism involving dityrosine formation. Compared to plasminogen activator inhibitor type-1 (PAI-1), both forms of PAI-2 are more resistant to hypochlorite-induced inactivation of its protease inhibitory activity. Holdase-type extracellular chaperone activity plays a putative non-canonical role for PAI-2. Our data demonstrate that glycosylated PAI-2 more efficiently inhibits the aggregation of Alzheimer's disease and preeclampsia-associated amyloid beta peptide (Aß), compared to non-glycosylated PAI-2 in vitro. However, hypochlorite-induced modification of non-glycosylated PAI-2 dramatically enhances its holdase activity by promoting the formation of very high-molecular-mass chaperone-active PAI-2 oligomers. Both PAI-2 forms protect against Aß-induced cytotoxicity in the SH-SY5Y neuroblastoma cell line in vitro. In the villous placenta, PAI-2 is localised primarily to syncytiotrophoblast with wide interpersonal variation in women with preeclampsia and in gestational-age-matched controls. Although intracellular PAI-2 and Aß staining localised to different placental cell types, some PAI-2 co-localised with Aß in the extracellular plaque-like aggregated deposits abundant in preeclamptic placenta. Thus, PAI-2 potentially contributes to controlling aberrant fibrinolysis and the accumulation of misfolded proteins in states characterised by oxidative and proteostasis stress, such as in Alzheimer's disease and preeclampsia.

Zinc Favors Triple-Negative Breast Cancer's Microenvironment Modulation and Cell Plasticity.

Triple-negative breast cancer (TNBC) tends to metastasize to the brain, a step that worsens the patient's prognosis. The specific hallmarks that determine successful metastasis are motility and invasion, microenvironment modulation, plasticity, and colonization. Zinc, an essential trace element, has been shown to be involved in all of these processes. In this work, we focus our attention on the potential role of zinc during TNBC metastasis. We used MDA-MB-BrM2 (BrM2) cells, a brain metastasis model derived from the parental TNBC cell line MDA-MB-231. Our studies show that BrM2 cells had double the zinc content of MDA-MB-231 cells. Moreover, exploring different metastatic hallmarks, we found that the zinc concentration is especially important in the microenvironment modulation of brain metastatic cells, enhancing the expression of SerpinB2. Furthermore, we show that zinc promotes the tumorigenic capacity of breast cancer stem cells. In addition, by causing a disturbance in MDA-MB-231 zinc homeostasis by overexpressing the Zip4 transporter, we were able to increase tumorigenicity. Nevertheless, this strategy did not completely recapitulate the BrM2 metastatic phenotype. Altogether, our work suggests that zinc plays an important role in the transformative steps that tumoral cells take to acquire tumorigenic potential and niche specificity.

Plasminogen activator Inhibitor-2 inhibits pulmonary arterial smooth muscle cell proliferation in pulmonary arterial hypertension via PI3K/Akt and ERK signaling.

BACKGROUND: The proliferation of pulmonary arterial smooth muscle cells (PASMCs) and subsequent pulmonary vascular remodeling leads to pulmonary arterial hypertension (PAH). Understanding the underlying mechanisms and identifying molecules that can suppress PASMCs proliferation is critical for developing effective pharmacological treatment. We previously showed that plasminogen activator inhibitor-2 (PAI-2) inhibited human PASMC (hPASMCs) proliferation in vitro. However, its inhibitory effect on PAH remains to be determined, and the mechanism remains to be illustrated. METHODS: We compared serum PAI-2 levels between PAH patients and healthy controls, and examined the correlation between PAI-2 level and disease severity. In monocrotaline-induced PAH rats, we examined the effects of exogenous PAI-2 administration on pulmonary vascular remodeling and PAH development. The effect of PAI-2 and potential mechanisms was further examined in cultured hPASMCs. RESULTS: The serum PAI-2 was decreased in PAH patients compared with controls. PAI-2 level was negatively correlated with mean pulmonary arterial pressure and estimated systolic pulmonary arterial pressure in ultrasonic cardiogram, while positively correlated with 6-min walking distance. In rats, administration of exogenous PAI-2 significantly reversed monocrotaline-induced PAH, as indicated by the decrease in right ventricle systolic pressure, right ventricular hypertrophy index and percent media thickness of pulmonary arterioles. Further mechanistic investigation in hPASMCs showed that PAI-2 inhibited cell proliferation by preventing the activation of PI3K/Akt and ERK pathways. CONCLUSION: PAI-2 is downregulated in PAH patients. PAI-2 attenuates PAH development by suppressing hPASMCs proliferation via the inhibition of PI3K/Akt and ERK pathways. PAI-2 may serve as a potential biomarker and therapeutic target for PAH.

The urokinase-type plasminogen activator and inhibitors in resectable lung adenocarcinoma.

BACKGROUND: The urokinase-type plasminogen activator (uPA) system is closely related to the occurrence and progression of cancer in many aspects. Previous studies demonstrated that the conclusions about the prognosis value of uPA, plasminogen activator inhibitor 1 (PAI-1) and plasminogen activator inhibitor 2 (PAI-2) in lung cancer are controversial, so this study was performed for the exploration of the predictive effect of uPA, PAI-1 and PAI-2 on the overall survival (OS) of resectable pulmonary adenocarcinoma patients. METHODS: UPA, PAI-1 and PAI-2 expression levels were assayed by immunohistochemical staining based on tissue microarray (TMA) that is composed of formalin-fixed paraffin-embedded specimens from 84 resectable lung adenocarcinoma patients from July 2004 to June 2009. The relationship of IHC, mRNA expression levels of three molecules were investigated respectively. The three molecules' relationship with clinicopathologic parameters and OS was explored by Chi-square, Kaplan-Meier, and Cox regression analyses. The Cancer Genome Atlas (TCGA) database was used to analyze differential gene expressions of RNA-sequencing data of pulmonary adenocarcinoma and normal tissues, and Kaplan-Meier methods were adopted to confirm the prognostic value of uPA, PAI-1 and PAI-2 in resectable lung adenocarcinoma in TCGA database and the R package MethylMix was used to conduct an analysis integrating methylation data and gene expression of RNA-sequencing data based on TCGA. RESULTS: UPA, PAI-1 and PAI-2 had much higher IHC expression levels in tumor than those in the normal tissues (uPA, Z = -10.511; PAI-1, Z = -4.836; PAI-2, Z = -6.794; all P < 0.0001). High DNA methylation level of gene uPA resulted in the decrease of its expression. In addition, expression level of PAI-2 was positively associated with tumor size (χ2 = 8.372, P =  0.004). Multivariate analyses showed TNM stage III was an independent adverse prognostic factor (hazard ratio = 3.736, 95 % confidence interval = 1.097-12.72, P =  0.035). Kaplan-Meier method revealed that uPA, PAI-1 and PAI-2 expression levels were not related to the OS for 84 resectable lung adenocarcinoma patients. According to TCGA data, PAI-1 expression level was identified as a potential adverse predictor for prognosis of resectable lung adenocarcinoma (Gehan-Breslow-Wilcoxon test, P = 0.025). CONCLUSIONS: Our data show that, the expression levels of uPA, PAI-1 and PAI-2 are significantly up-regulated in resectable lung adenocarcinoma. Besides, this study highlights PAI-1 as a latent adverse prognostic factor in resectable adenocarcinoma of lung.

SASP-Dependent Interactions between Senescent Cells and Platelets Modulate Migration and Invasion of Cancer Cells.

Alterations in platelet aggregation are common in aging individuals and in the context of age-related pathologies such as cancer. So far, however, the effects of senescent cells on platelets have not been explored. In addition to serving as a barrier to tumor progression, cellular senescence can contribute to remodeling tissue microenvironments through the capacity of senescent cells to synthesize and secrete a plethora of bioactive factors, a feature referred to as the senescence-associated secretory phenotype (SASP). As senescent cells accumulate in aging tissues, sites of tissue injury, or in response to drugs, SASP factors may contribute to increase platelet activity and, through this mechanism, generate a microenvironment that facilitates cancer progression. Using in vitro models of drug-induced senescence, in which cellular senescence was induced following exposure of mammary epithelial cells (MCF-10A and MCF-7) and gastric cancer cells (AGS) to the CDK4/6 inhibitor Palbociclib, we show that senescent mammary and gastric cells display unique expression profiles of selected SASP factors, most of them being downregulated at the RNA level in senescent AGS cells. In addition, we observed cell-type specific differences in the levels of secreted factors, including IL-1ß, in media conditioned by senescent cells. Interestingly, only media conditioned by senescent MCF-10A and MCF-7 cells were able to enhance platelet aggregation, although all three types of senescent cells were able to attract platelets in vitro. Nevertheless, the effects of factors secreted by senescent cells and platelets on the migration and invasion of non-senescent cells are complex. Overall, platelets have prominent effects on migration, while factors secreted by senescent cells tend to promote invasion. These differential responses likely reflect differences in the specific arrays of secreted senescence-associated factors, specific factors released by platelets upon activation, and the susceptibility of target cells to respond to these agents.

The Kindlin2-p53-SerpinB2 signaling axis is required for cellular senescence in breast cancer.

In cancer, cellular senescence is a complex process that leads to inhibition of proliferation of cells that may develop a neoplastic phenotype. A plethora of signaling pathways, when dysregulated, have been shown to elicit a senescence response. Two well-known tumor suppressor pathways, controlled by the p53 and retinoblastoma proteins, have been implicated in maintaining the cellular senescence phenotype. Kindlin-2, a member of an actin cytoskeleton organizing and integrin activator proteins, has been shown to play a key role in the regulation of several hallmarks of several cancers, including breast cancer (BC). The molecular mechanisms whereby Kindlin-2 regulates cellular senescence in BC tumors remains largely unknown. Here we show that Kindlin-2 regulates cellular senescence in part through its interaction with p53, whereby it regulates the expression of the p53-responsive genes; i.e., SerpinB2 and p21, during the induction of senescence. Our data show that knockout of Kindlin-2 via CRISPR/Cas9 in several BC cell lines significantly increases expression levels of both SerpinB2 and p21 resulting in the activation of hallmarks of cellular senescence. Mechanistically, interaction between Kindlin-2 and p53 at the promotor level is critical for the regulated expression of SerpinB2 and p21. These findings identify a previously unknown Kindlin-2/p53/SerpinB2 signaling axis that regulates cellular senescence and intervention in this axis may serve as a new therapeutic window for BCs treatment.

An Endogenous Anti-aging Factor, Sonic Hedgehog, Suppresses Endometrial Stem Cell Aging through SERPINB2.

Endometrial stem cells are located in the basal layer of the endometrium, and they are responsible for the cyclic regeneration of the uterus during the menstrual cycle. Recent studies have revealed that recurrent pregnancy loss is associated with an age-related stem cell deficiency in the endometrium. Therefore, intensive study of endometrial stem cell aging may provide new insights for preventing recurrent pregnancy loss. Sonic hedgehog (SHH) signaling has been identified as a morphogen during the embryonic development processes. In addition to this canonical function, we found that the age-associated decline in regenerative potential in the endometrium may be due to decreased SHH-signaling integrity in local stem cells with aging. Importantly, the current study also showed that SHH activity clearly declines with aging both in vitro and in vivo, and exogenous SHH treatment significantly alleviates various aging-associated declines in multiple endometrial stem cell functions, suggesting that SHH may act as an endogenous anti-aging factor in human endometrial stem cells. Moreover, we found that stem cell senescence may enhance SERPINB2 expression, which in turn mediates the effect of SHH on alleviating senescence-induced endometrial stem cell dysfunctions, suggesting that SERPINB2 is a master regulator of SHH signaling during the aging process.

SERPINB2 overexpression inhibited cell proliferation, invasion and migration, led to G2/M arrest, and increased radiosensitivity in nasopharyngeal carcinoma cells.

The aim of this study was to evaluate the effect of SERPINB2 on cell proliferation, cell cycle, epithelial-mesenchymal transition (EMT), invasion, migration, and radiosensitivity in nasopharyngeal carcinoma cells. Both CNE2R and CNE2 cells were transfected with pEGFP-N1-SERPINB2. Cell proliferation was measured by MTT assay, cell cycle by flow cytometry, and SERpINB2 expression by quantitative real-time polymerase chain reaction (qRT-PCR). Western blot was carried out to detect the protein expression. In addition, SERPINB2 and ß-catenin were located intracellularly using an immunofluorescent assay, and cell migration and invasion were measured by wound healing and Transwell assays, respectively. Radiosensitivity was assessed using colony formation and MTT assays. SERPINB2 expression was downregulated in CNE2R cells. After transfection with pEGFP-N1-SERPINB2, the OD values were decreased, and there was an increased fraction in the G2/M phase. Moreover, SERPINB2 overexpression could inhibit the invasion and migration capabilities of CNE2R and CNE2 cells, with downregulation of vimentin, N-cadherin, nuclear ß-catenin, matrix metalloproteinase (MMP)-2 and MMP-9, and upregulation of E-cadherin. Moreover, transfection with the SERPINB2 plasmid reduced the growth rate of CNE2R cells at doses of 2, 4 and 6 Gy, and also decreased the surviving fractions. Overexpression of SERPINB2 could reduce the proliferation, invasion and migration capabilities of CNE2R and CNE2 cells, and led to G2/M arrest via EMT inhibition, and this may be a potential strategy for enhancing the radiation sensitivity of nasopharyngeal carcinoma cells.

Genetic programming of macrophages generates an in vitro model for the human erythroid island niche.

Red blood cells mature within the erythroblastic island (EI) niche that consists of specialized macrophages surrounded by differentiating erythroblasts. Here we establish an in vitro system to model the human EI niche using macrophages that are derived from human induced pluripotent stem cells (iPSCs), and are also genetically programmed to an EI-like phenotype by inducible activation of the transcription factor, KLF1. These EI-like macrophages increase the production of mature, enucleated erythroid cells from umbilical cord blood derived CD34+ haematopoietic progenitor cells and iPSCs; this enhanced production is partially retained even when the contact between progenitor cells and macrophages is inhibited, suggesting that KLF1-induced secreted proteins may be involved in this enhancement. Lastly, we find that the addition of three secreted factors, ANGPTL7, IL-33 and SERPINB2, significantly enhances the production of mature enucleated red blood cells. Our study thus contributes to the ultimate goal of replacing blood transfusion with a manufactured product.

SerpinB2 is involved in cellular response upon UV irradiation.

Ultraviolet light induced pyrimidine dimer is a helix distortion DNA damage type, which recruits repair complexes. However, proteins of these complexes that take part in both DNA damage recognition and repair have been well-described, the regulation of the downstream steps of nucleotide excision repair (NER) have not been clearly clarified yet. In a high-throughput screen, we identified SerpinB2 (SPB2) as one of the most dramatically upregulated gene in keratinocytes following UV irradiation. We found that both the mRNA and the protein levels of SPB2 were increased upon UV irradiation in various cell lines. Additionally, UV damage induced translocation of SPB2 from the cytoplasm to the nucleus as well as the damage induced foci formation of it. Here we show that SPB2 co-localizes with XPB involved in the NER pathway at UV-induced repair foci. Finally, we demonstrated that UV irradiation promoted the association of SPB2 with ubiquitylated proteins. In basal cell carcinoma tumour cells, we identified changes in the subcellular localization of SPB2. Based on our results, we conclude that SPB2 protein has a novel role in UV-induced NER pathway, since it regulates the removal of the repair complex from the damaged site leading to cancerous malformation.

The role of SerpinB2 in human bronchial epithelial cells responses to particulate matter exposure.

Exposure to particulate matter (PM) has been related to the onset of adverse health effects including lung cancer, but the underlying molecular mechanisms are still under investigation. Epithelial-to-mesenchymal transition (EMT) is regarded as a crucial step in cancer progression. In a previous study, we reported EMT-related responses in the human bronchial epithelial cell line HBEC3-KT, exposed to Milan airborne winter PM2.5. We also found a strong modulation of SERPINB2, encoding for the PAI-2 protein and previously suggested to play an important role in cancer. Here we investigate the role of SERPINB2/PAI-2 in the regulation of EMT-related effects induced by PM exposure in HBEC3-KT. PM exposure (up to 10 µg/cm2) increased SERPINB2 expression, reduced cell migration and induced morphological alterations in HBEC3-KT. Changes in actin structure and cadherin-1 relocalization were observed in PM-exposed samples. Knockdown of SERPINB2 by siRNA down-regulated the CDH1 gene expression, as well as PAI-2 and cadherin-1 protein expression. SERPINB2 knockdown also increased cell migration rate, and counteracted the PM-induced reduction of cell migration and alteration of cell morphology. SERPINB2 was found to be greatly down-regulated in a HBEC2-KT transformed cell line, supporting the importance of this gene in the regulation of EMT. In conclusion, here we show that PAI-2 regulates CDH1 gene/cadherin-1 protein expression in bronchial HBEC3-KT cells, and this mechanism might be involved in the regulation of cell migration. SERPINB2 down-regulation should be considered part of EMT, and the over-expression of SERPINB2 in PM-exposed samples might be interpreted as an initial protective mechanism.

Effect of sex steroid hormone fluctuations in the pathophysiology of male-retinal pigment epithelial cells.

Gender-based differences may influence the occurrence of several ocular conditions suggesting the possibility that fluctuations in sex steroid homeostasis may have direct effects on the eye physiology. Here, we evaluated the effect of sex steroid hormone fluctuations in male retinal pigment epithelial cells, RPEs (ARPE-19). To mimic hormonal fluctuations occurring during aging, we exposed ARPE-19 to acute, prolonged or chronic estradiol, and progesterone challenges. We found that chronic estradiol treatment promotes a remarkable necrosis of RPE cells, and does not affect pRb2/p130 or PAI-2 sub-cellular localization. In contrast, chronic progesterone exposure induces nuclear subcellular rearrangement of pRb2/p130, co-immunolocalization of pRb2/p130 with PAI-2, and accumulation of cells in G2/M phase, which is accompanied by a remarkable reduction of necrosis in favour of apoptosis activation. This study has a high clinical significance since it considers sex steroid fluctuations as inducers of milieu change in the retina able to influence pathological situations occurring with aging in non-reproductive systems such as the eye. Exogenous administration of physiologically significant amounts of sex hormones for long periods of time is a common clinical practice for transgender patients seeking sex reassignment. In particular, our study offers the unique opportunity to unravel the effects of sex hormones, not only in determining gender differences but also in affecting the physiology of non-reproductive systems, such as the eye, in the underserved transgender community.

The urokinase plasminogen activation system in gastroesophageal cancer: A systematic review and meta-analysis.

BACKGROUND: The urokinase plasminogen activation (uPA) system is a crucial pathway for tumour invasion and establishment of metastasis. Although there is good evidence that uPA system expression is a clinically relevant biomarker in some solid tumours, its role in gastroesophageal cancer is uncertain. RESULTS: We identified 22 studies encompassing 1966 patients which fulfilled the inclusion criteria. uPA, uPAR, or PAI-1 expression is significantly associated with high risk clinicopathological features. High uPA expression is associated with a shorter RFS (HR 1.90 95% 1.16-3.11, p = 0.01) and OS (HR 2.21 95% CI 1.74-2.80, p < 0.0001). High uPAR expression is associated with poorer OS (HR 2.21 95%CI 1.82-2.69, p < 0.0001). High PAI-1 expression is associated with shorter RFS (HR 1.96 96% CI 1.07-3.58, p = 0.03) and OS (HR 1.84 95%CI 1.28-2.64, p < 0.0001). There was no significant association between PAI-2 expression and OS (HR 0.97 95%CI 0.48-1.94, p < 0.92) although data was limited. MATERIALS AND METHODS: We undertook a systematic review evaluating expression of uPA, urokinase plasminogen activator receptor (uPAR), plasminogen activator inhibitor-1 (PAI-1/SerpinE1) and plasminogen activator inhibitor-2 (PAI-2/SerpinB2) on primary oesophageal, gastro-oesophageal junction, and gastric adenocarcinomas. We performed a meta-analysis of clinicopathological associations, overall survival (OS) and recurrence free survival (RFS). CONCLUSIONS: We conclude that the uPA system is a clinically relevant biomarker in primary gastroesophageal cancer, with higher expression of uPA, uPAR and PAI-1 associated with higher risk disease and poorer prognosis. This also highlights the potential utility of the uPA system as a therapeutic target for improved treatment strategies.

SerpinB2 regulates stromal remodelling and local invasion in pancreatic cancer.

Pancreatic cancer has a devastating prognosis, with an overall 5-year survival rate of ~8%, restricted treatment options and characteristic molecular heterogeneity. SerpinB2 expression, particularly in the stromal compartment, is associated with reduced metastasis and prolonged survival in pancreatic ductal adenocarcinoma (PDAC) and our genomic analysis revealed that SERPINB2 is frequently deleted in PDAC. We show that SerpinB2 is required by stromal cells for normal collagen remodelling in vitro, regulating fibroblast interaction and engagement with collagen in the contracting matrix. In a pancreatic cancer allograft model, co-injection of PDAC cancer cells and SerpinB2-/- mouse embryonic fibroblasts (MEFs) resulted in increased tumour growth, aberrant remodelling of the extracellular matrix (ECM) and increased local invasion from the primary tumour. These tumours also displayed elevated proteolytic activity of the primary biochemical target of SerpinB2-urokinase plasminogen activator (uPA). In a large cohort of patients with resected PDAC, we show that increasing uPA mRNA expression was significantly associated with poorer survival following pancreatectomy. This study establishes a novel role for SerpinB2 in the stromal compartment in PDAC invasion through regulation of stromal remodelling and highlights the SerpinB2/uPA axis for further investigation as a potential therapeutic target in pancreatic cancer.

Imaging of Angiotropism/Vascular Co-Option in a Murine Model of Brain Melanoma: Implications for Melanoma Progression along Extravascular Pathways.

Angiotropism/pericytic mimicry and vascular co-option involve tumor cell interactions with the abluminal vascular surface. These two phenomena may be closely related. However, investigations of the two processes have developed in an independent fashion and different explanations offered as to their biological nature. Angiotropism describes the propensity of tumor cells to spread distantly via continuous migration along abluminal vascular surfaces, or extravascular migratory metastasis (EVMM). Vascular co-option has been proposed as an alternative mechanism by which tumors cells may gain access to a blood supply. We have used a murine brain melanoma model to analyze the interactions of GFP human melanoma cells injected into the mouse brain with red fluorescent lectin-labeled microvascular channels. Results have shown a striking spread of melanoma cells along preexisting microvascular channels and features of both vascular co-option and angiotropism/pericytic mimicry. This study has also documented the perivascular expression of Serpin B2 by angiotropic melanoma cells in the murine brain and in human melanoma brain metastases. Our findings suggest that vascular co-option and angiotropism/pericytic mimicry are closely related if not identical processes. Further studies are needed in order to establish whether EVMM is an alternative form of cancer metastasis in addition to intravascular cancer dissemination.

Exposure to airborne PM2.5 suppresses microRNA expression and deregulates target oncogenes that cause neoplastic transformation in NIH3T3 cells.

Long-term exposure to airborne PM2.5 is associated with increased lung cancer risk but the underlying mechanism remains unclear. We characterized global microRNA and mRNA expression in human bronchial epithelial cells exposed to PM2.5 organic extract and integrally analyzed microRNA-mRNA interactions. Foci formation and xenograft tumorigenesis in mice with NIH3T3 cells expressing genes targeted by microRNAs were performed to explore the oncogenic potential of these genes. We also detected plasma levels of candidate microRNAs in subjects exposed to different levels of air PM2.5 and examined the aberrant expression of genes targeted by these microRNAs in human lung cancer. Under our experimental conditions, treatment of cells with PM2.5 extract resulted in downregulation of 138 microRNAs and aberrant expression of 13 mRNAs (11 upregulation and 2 downregulation). In silico and biochemical analyses suggested SLC30A1, SERPINB2 and AKR1C1, among the upregulated genes, as target for miR-182 and miR-185, respectively. Ectopic expression of each of these genes significantly enhanced foci formation in NIH3T3 cells. Following subcutaneous injection of these cells into nude mice, fibrosarcoma were formed from SLC30A1- or SERPINB2-expressing cells. Reduced plasma levels of miR-182 were detected in subjects exposed to high level of PM2.5 than in those exposed to low level of PM2.5 (P = 0.043). Similar results were seen for miR-185 although the difference was not statistically significant (P = 0.328). Increased expressions of SLC30A1, SERPINB2 and AKR1C1 were detected in human lung cancer. These results suggest that modulation of miR-182 and miR-185 and their target genes may contribute to lung carcinogenesis attributable to PM2.5 exposure.

Plasminogen Activator Inhibitor-2 Plays a Leading Prognostic Role among Protease Families in Non-Small Cell Lung Cancer.

BACKGROUND: In lung cancer, uPA, its receptor (uPAR), and the inhibitors PAI-1 and PAI-2 of the plasminogen activator family interact with MMP-2 and MMP-9 of the MMP family to promote cancer progression. However, it remains undetermined which of these markers plays the most important role and may be the most useful indicator to stratify the patients by risk. METHODS: We determined the individual prognostic value of these 6 markers by analyzing a derivation cohort with 98 non-small cell lung cancer patients by immunohistochemical staining. The correlation between the IHC expression levels of these markers and disease prognosis was investigated, and an immunohistochemical panel for prognostic prediction was subsequently generated through prognostic model analysis. The value of the immunohistochemical panel was then verified by a validation cohort with 91 lung cancer patients. RESULTS: In derivation cohort, PAI-2 is the most powerful prognostic factor (HR = 2.30; P = 0.001), followed by MMP-9 (HR = 2.09; P = 0.019) according to multivariate analysis. When combining PAI-2 and MMP-9, the most unfavorable prognostic group (low PAI-2 and high MMP-9 IHC expression levels) showed a 6.40-fold increased risk of a poor prognosis compared to the most favorable prognostic group (high PAI-2 and low MMP-9 IHC expression levels). PAI-2 and MMP-9 IHC panel could more precisely identify high risk patients in both derivation and validation cohort. CONCLUSIONS: We revealed PAI-2 as the most powerful prognostic marker among PA and MMP protease family even after considering their close relationships with each other. By utilizing a combination of PAI-2 and MMP-9, more precise prognostic information than merely using pathological stage alone can be obtained for lung cancer patients.