Tumor-associated stromal cells expressing E-prostanoid 2 or 3 receptors in prostate cancer: correlation with tumor aggressiveness and outcome by angiogenesis and lymphangiogenesis

Oral administration of E-type prostanoid (EP) 1 receptor antagonist suppresses carcinogenesis and development of prostate cancer via upregulation of apoptosis in an animal model

Prostaglandin E2 plays an important role in carcinogenesis and malignant potential of prostate cancer (PC) cells by binding to its specific receptors, E-type prostanoid (EP) receptors. However, anti-carcinogenic effects of the EP receptor antagonist are unclear. In this study, we used a mouse model of PC. The mice were provided standard feed (control) or feed containing the EP1 receptor antagonist and were sacrificed at 10, 15, 30, and 52 weeks of age. Apoptosis was evaluated by immunohistochemical analysis using a cleaved caspase-3 assay. The incidence of cancer in the experimental group was significantly lower than that in the control group at 15, 30, and 52 weeks of age. The percentage of poorly differentiated PC cells was significantly lower in the experimental group than in the control group at 30 and 52 weeks of age. The percentage of apoptotic cells in the experimental group was significantly higher than that in the control group at 15, 30, and 52 weeks of age. These findings indicate that feeding with the addition of EP1 receptor antagonist delayed PC progression via the upregulation of apoptosis. We suggest that the EP1 receptor antagonist may be a novel chemopreventive agent for PC.

Vitamin D in prostate cancer

Signaling through the vitamin D receptor has been shown to be biologically active and important in a number of preclinical studies in prostate and other cancers. Epidemiologic data also indicate that vitamin D signaling may be important in the cause and prognosis of prostate and other cancers. These data indicate that perturbation of vitamin D signaling may be a target for the prevention and treatment of prostate cancer. Large studies of vitamin D supplementation will be required to determine whether these observations can be translated into prevention strategies. This paper reviews the available data in the use of vitamin D compounds in the treatment of prostate cancer. Clinical data are limited which support the use of vitamin D compounds in the management of men with prostate cancer. However, clinical trials guided by existing preclinical data are limited.

Inhibition of Ep3 attenuates migration and promotes apoptosis of non-small cell lung cancer cells via suppression of TGF-β/Smad signaling

Non-small cell lung cancer (NSCLC) is the most common cause of cancer-associated mortality worldwide. Prostaglandin E2 (PGE2) regulates various biological processes, including invasion, proliferation and apoptosis. E-prostanoid 3 (Ep3) is a PGE2 receptor, and the functional role of Ep3 in the progression of NSCLC remains unresolved. The present study investigated the effects of Ep3 in A549 cells and explored the underlying molecular mechanisms. The results revealed that the mRNA and protein expression levels of Ep3 were significantly upregulated in NSCLC tissues and A549 cells. Pharmacological inhibition of Ep3 or RNA interference against Ep3 attenuated the cell viability, migration and invasion, and promoted apoptosis in A549 cells. Ep3 deficiency also decreased the expression of transforming growth factor (TGF)-β, phosphorylated (p)-Smad2 and p-Smad3. The transfection of TGF-β overexpression plasmids reversed the effects of Ep3 deficiency on the cell viability and apoptosis in A549 cells. Finally, an in vivo experiment revealed that Ep3-siRNA transfection strongly reduced the tumor growth and tumor volume. The Ep3-siRNA transfection also inhibited tumor metastasis via suppression of the expression of metastasis-associated proteins. Taken together, these findings indicate that inhibition of Ep3 attenuates the viability and migration, and promotes the apoptosis of NSCLC through suppression of the TGF-β/Smad signaling pathway. Targeting of the Ep3/TGF-β/Smad signaling pathway may be a novel therapeutic strategy for the prevention and treatment of NSCLC.

Calcitriol and cancer therapy: A missed opportunity

The vitamin D receptor is expressed in most tissues of the body - and the cancers that arise from those tissues. The vitamin D signaling pathway is active in those tissues and cancers. This is at least consistent with the hypothesis that perturbing this signaling may have a favorable effect on the genesis and growth of cancers. Epidemiologic data indicate that vitamin D signaling may be important in the initiation and outcome of a number of types of cancer. Many studies have shown that calcitriol (1,25 dihydroxycholecalciferol) and other vitamin D compounds have antiproliferative, pro-apoptotic, anti-cell migration and antiangiogenic activity in a number of preclinical studies in many different cancer types. Unfortunately, the assessment of the activity of calcitriol or other vitamin D analogues in the treatment of cancer, as single agents or in combination with other anticancer agents has been stymied by the failure to adhere to commonly accepted principles of drug development and clinical trials conduct.

CD163 as a marker of M2 macrophage, contribute to predicte aggressiveness and prognosis of Kazakh esophageal squamous cell carcinoma

M2 macrophages was domesticated by tumor microenvironment to produce some angiogenic molecules and protease, facilitating angiogenesis and matrix breakdown, promoting tumor invasive and metastasis. However, The function of M2 macrophages to progression of esophageal carcinoma, especially Kazakh esophageal carcinoma is still dimness. This study aims to investigate M2 macrophages correlated with matrix metalloproteinase-9 (MMP9) and microvessel density, and the role in the progression of Kazakh esophageal squamous cell carcinoma. CD163 and CD34 as the marker of M2 macrophages and endothelial cells, were used to identify the M2 macrophages density and microvessel density, respectively. Immunohistochemistry staining was evaluated the expression of MMP9. The number of infiltrated CD163-positive M2 macrophages in tumor islets and stroma was significantly higher than in cancer adjacent normal tissues. The increased of M2 macrophages and microvessel density were significantly correlated with more malignant phenotypes including lymph node metastasis and clinical stage progression. Meanwhile, the expression of MMP9 showed much higher level in esophageal squamous cell carcinoma than that in cancer adjacent normal tissues, and high expression of MMP9 in Kazakh esophageal squamous cell carcinoma was significantly associated with age, depth of tumor invasion, lymph node metastasis, and tumor clinical stage. The quantity of M2 macrophages in tumor stroma was positively associated with microvessel density and the expression of MMP9, and as an independent poorly prognostic factor for overall survival time of Kazakh esophageal squamous cell carcinoma. These findings suggest the increased number of M2 macrophages correlated with high expression of MMP9 and high microvessel density may contribute to the tumor aggressiveness and angiogenesis, promoting the progression of Kazakh esophageal squamous cell carcinoma.

The Prostaglandin EP3 Receptor Is an Independent Negative Prognostic Factor for Cervical Cancer Patients

We know that one of the main risk factors for cervical cancer is an infection with high-risk human papillomavirus (HR-HPV). Prostaglandins and their receptors are very important for the tumour growth and tumour-associated angiogenesis. Little is known about the expression of the Prostaglandin E receptor type 3 (EP3) or the Prostaglandin (PG)E₂-EP3 signalling in cervical cancer, so the aim of the study was to analyse the expression of the EP3 receptor in cervical cancer and find prognostic factors in relation to survival; EP3 immunohistological staining of 250 cervical cancer slides was performed and analysed with a semi-quantitative score. The statistical evaluation was performed with Statistical Package for the Social Sciences (SPSS) to evaluate the staining results and the survival analyses of the cervical cancer cases. A significant difference was observed in EP3 expression in Fédération Internationale de Gynécologie et d’Obstétrique (FIGO) stadium I versus FIGO stadium II–IV cases. High expression of EP3 (IRS ≥ 1.5) in cervical cancer patients was correlated with poor prognosis in overall survival rates. Survival in adenocarcinoma (AC) of the cervix was lower than in squamous cell carcinoma (SCC). Cox regression analysis shows that EP3 is an independent prognosticator. In this study we could show that the membrane-bound prostaglandin receptor EP3 is an independent prognosticator for cervical cancer patient survival. Targeting the EP3 receptor seems to be an interesting candidate for endocrine therapy. Therefore, more research is needed on the influence of the receptor system and its influence on cervical cancer growth.

Prostaglandin E2-EP2 signaling as a node of chronic inflammation in the colon tumor microenvironment

Background

Colorectal cancer is the third most common cancer. Involvement of prostaglandin (PG) system in the pathogenesis of colorectal cancer has been suggested from clinical studies demonstrating therapeutic effect of NSAIDs including aspirin or selective COX-2 inhibitors. However, mechanisms on how PG regulates inflammatory responses leading to colorectal cancer development remain obscure. Further, careful attention is needed to use these drugs for a long time because of adverse effects due to non-specific inhibition of physiological PG production in addition to pathological one, making the development of alternatives to aspirin important. Recent studies using mouse model of colitis-associated colon cancer, azoxymethane (AOM)-dextran sodium sulfate (DSS) model, have revealed some of the mechanisms on how PG regulates inflammation in lesions and proposed PG receptor as a therapeutic target.

Main body of abstract

Among each PG receptor subtype examined, prostaglandin E receptor 2 (EP2) signaling specifically contributes to colorectal cancer formation and inflammation in lesions of AOM-DSS model. EP2 is expressed in neutrophils, infiltrated major inflammatory cells, and tumor-associated fibroblasts (TAFs) in the tumor stroma of this mouse model and also in clinical specimen from ulcerative colitis-associated colorectal cancer. Bone marrow transfer experiments between wild-type and EP2-deficient mice have confirmed the involvement of EP2 signaling in these two types of cells in the pathogenesis of the disease. EP2 signaling in both types of cells regulates the transition to and maintenance of inflammation in multiple steps to shape the tumor microenvironment which contributes to trigger and promote colorectal cancer. In this process, PGE₂-EP2 signaling synergizes with TNF-α to amplify TNF-α-induced inflammatory responses, forms a positive feedback loop involving COX-2-PGE₂-EP2 signaling to exacerbate PG-mediated inflammation once triggered, and alternates active cell populations participating in inflammation through forming self-amplification loop among neutrophils. Thus, EP2 signaling functions as a node of inflammatory responses in the tumor microenvironment. Based on such a notion, EP2 can become a strong candidate for therapeutic target of colorectal cancer treatment. Indeed, in AOM-DSS model, a selective EP2 antagonist, PF-04418948, potently suppresses colorectal tumor formation.

Short conclusion

PGE₂-EP2 signaling functions as a node of chronic inflammation which shapes the tumor microenvironment and thus is a strong candidate of target for the chemoprevention of colorectal cancer.

DDR1 enhances invasion and metastasis of gastric cancer via epithelial-mesenchymal transition

In this study, we investigated the effects of DDR1 on the invasion and metastasis in gastric cancer (GC) via epithelial-mesenchymal transition (EMT). Immunohistochemistry analysis was used to detect DDR1, E-cadherin, and Vimentin expression in GC tissues as well as DDR1 expression in GC cell lines and normal gastric epithelial cells. The relationship between DDR1 expression and EMT in GC cell lines was explored by down and upregulating DDR1 and examining corresponding changes in the expression of EMT-related proteins and in biological characteristics. Furthermore, a nude mice model with a transplantation tumor generating from stably transfected GC cells with DDR1 overexpression was established and performed to further reveal the effects of DDR1 expression on cellular morphology and growth of GC. Our results showed that DDR1 was highly expressed in GC tissues and cell lines compared with adjacent tissues and normal cell line, and its expression was significantly higher in GC having poor differentiation (p < 0.01), advanced depth of wall invasion (p = 0.020), lymph node metastasis (p = 0.0001), liver metastasis (p < 0.01), and high TNM stage (p < 0.01). Western blot analyses revealed that DDR1 overexpression resulted in a significant decrease in the expression of E-cadherin (p < 0.01) and an increase in the expression of Vimentin and Snail (p < 0.01), while knockdown of DDR1 led to opposite outcomes. We further demonstrated that DDR1 overexpression promoted GC cell proliferation (p < 0.05), migration (p < 0.01), and invasion (p < 0.01), and accelerated the growth (p < 0.05) as well as the microvessel formation (p < 0.01) of transplantation tumor in nude mice. Our study establishes that DDR1 enhances invasion and metastasis of gastric cancer via EMT.

Microvascular density and immunohistochemical expression of VEGF, VEGFR-1 and VEGFR-2 in benign prostatic hyperplasia, high-grade prostate intraepithelial neoplasia and prostate cancer

INTRODUCTION

The aim of our study was to determine and compare angiogenesis in benign prostatic hyperplasia (BPH), high-grade prostate intraepithelial neoplasia (HGPIN) and prostate cancer (Pca). Moreover, we evaluated its role as a prognostic factor for Pca.

MATERIAL AND METHODS

We examined 39, 12 and 51 samples of BPH, HGPIN and Pca, respectively. Immunohistochemical methods were applied in order to evaluate the expression of VEGF and its receptors (VEGFR-1, VEGFR-2), while microvascular density (MVD) was determined using CD105. In Pca samples, we recorded stage, differentiation, perineural invasion, adjuvant radiotherapy and their correlation with angiogenesis.

RESULTS

225 The expression of VEGF, VEGFR-1 and VEGFR-2 was significantly higher in Pca than compared to BPH (p <0.001, p <0.001 and p <0.001, respectively) and HGPIN (p <0.001, p <0.001 and p = 0.04, respectively), while there was no difference between BPH and HGPIN. MVD was higher in Pca compared to BPH (p <0.001) and HGPIN (p <0.01), while there was no difference between BPH and HGPIN. VEGF expression and MVD were significantly greater in Pca samples with poor differentiation (p = 0.044 and p = 0.038, respectively) and perineural invasion (p <0.001 and p = 0.019, respectively), while overexpression of VEGF was associated with advanced pathological stage (p = 0.047).

CONCLUSIONS

Angiogenesis is more prominent in Pca than in BPH and HGPIN, while there is no difference between BPH and HGPIN. Pharmaceutical inhibition of angiogenesis could be a valuable therapeutic option for Pca in the near future.

Expression of prostaglandin E2 prostanoid receptor EP2 and interleukin-1β in laryngeal carcinoma - preliminary study

Aim of the study

Expression of EP2 protein, the prostaglandin E₂ (PGE₂) receptor, produced by tumour microenvironment inflammatory cells as well as tumour cells, may promote cellular proliferation and growth in an autocrine and paracrine fashion. The phenomenon involving these proteins is regulated by interleukin 1β (IL-1β). Many researchers indicate a connection of EP2 and IL-1β in various types of neoplasms with higher tumour progression and poor prognosis. The aim of this study was to analyse the EP2 expression within laryngeal carcinoma tissue and IL-1β levels in peripheral blood mononuclear cell supernatants and to find relationships between clinicomorphological features.

Material and methods

A group of 50 patients with verified squamous cell laryngeal carcinoma was analysed in this study. The pathological evaluation included pTNM depth of invasion according to tumour front grading criteria. Immunohistochemical analysis for membranous staining of EP2 in tumour tissues was used. The IL-1β expression was determined by enzyme-linked immunosorbent assay (ELISA).

Results

Increased EP2 expression in carcinoma cells was confirmed for more advanced tumours (pT3-pT4 vs. pT1-pT2, p < 0.0001 and pN1-3 vs. pN0, p = 0.02). Tumours with the highest aggressiveness identified by deeper invasion of submucosa or cartilage were characterised by the highest expression of EP2 (p < 0.0001). In laryngeal carcinomas characterised by a lower differentiation the highest EP2 expression in tumour cells was noted (p = 0.009). A positive relationship between IL-1β expression and the presence of lymph node metastases was also confirmed (p = 0.04).

Conclusions

The study indicates the potential effect of EP2 receptor and IL-1β on tumour progression in laryngeal carcinoma.

Combination of Quercetin and 2-Methoxyestradiol Enhances Inhibition of Human Prostate Cancer LNCaP and PC-3 Cells Xenograft Tumor Growth

Quercetin and 2-Methoxyestradiol (2-ME) are promising anti-cancer substances. Our previous in vitro study showed that quercetin synergized with 2-Methoxyestradiol exhibiting increased antiproliferative and proapoptotic activity in both androgen-dependent LNCaP and androgen-independent PC-3 human prostate cancer cell lines. In the present study, we determined whether their combination could inhibit LNCaP and PC-3 xenograft tumor growth in vivo and explored the underlying mechanism. Human prostate cancer LNCaP and PC-3 cells were inoculated subcutaneously in male BALB/c nude mice. When xenograft tumors reached about 100 mm³, mice were randomly allocated to vehicle control, quercetin or 2-Methoxyestradiol singly treated and combination treatment groups. After therapeutic intervention for 4 weeks, combination treatment of quercetin and 2-ME i) significantly inhibited prostate cancer xenograft tumor growth by 46.8% for LNCaP and 51.3% for PC-3 as compared to vehicle control group, more effective than quercetin (28.4% for LNCaP, 24.8% for PC3) or 2-ME (32.1% for LNCaP, 28.9% for PC3) alone; ii) was well tolerated by BALB/c mice and no obvious toxic reactions were observed; iii) led to higher Bax/Bcl-2 ratio, cleaved caspase-3 protein expression and apoptosis rate; and iv) resulted in lower phosphorylated AKT (pAKT) protein level, vascular endothelial growth factor protein and mRNA expression, microvascular density and proliferation rate than single drug treatment. These effects were more remarkable compared to vehicle group. Therefore, combination of quercetin and 2-ME can serve as a novel clinical treatment regimen owning the potential of enhancing antitumor effect on prostate cancer in vivo and lessening the dose and side effects of either quercetin or 2-ME alone. These in vivo results will lay a further solid basis for subsequent researches on this novel therapeutic regimen in human prostate cancer.

Evaluation of prostaglandin E2 and E-series prostaglandin receptor in patients with interstitial cystitis

PURPOSE

We evaluated PGE2 and EP receptor in patients with interstitial cystitis.

MATERIALS AND METHODS

Enrolled in the study were 20 female patients with interstitial cystitis (11 with and 9 without Hunner lesions), 9 female controls with another urological disease who needed a cystoscopic procedure and 10 normal volunteers. In all participants we determined O'Leary-Sant symptom and problem scores, and obtained voluntary urine specimens for PGE2 analysis. Using anesthesia the bladder was distended by saline in stepwise fashion from 100 ml to maximum capacity in patients with interstitial cystitis. Each time the infused saline was retrieved for PGE2 analysis. We also measured PGE2 and the expression of EP receptor mRNA in bladder biopsy tissue in patients with interstitial cystitis.

RESULTS

Symptom and problem indexes in patients with interstitial cystitis and Hunner lesions were significantly higher than in patients with interstitial cystitis without Hunner lesions. Urinary PGE2 in patients with interstitial cystitis and Hunner lesions was significantly higher than in patients with interstitial cystitis without lesions, controls and normal volunteers. PGE2 in retrieved saline in patients with interstitial cystitis and Hunner lesions increased depending on infusion volume but not in patients with interstitial cystitis without lesions. PGE2 content in bladder biopsy tissue was significantly higher in patients with interstitial cystitis and Hunner lesions than in controls. In patients with interstitial cystitis and Hunner lesions the expression of EP1 and EP2 mRNA was significantly higher than in controls.

CONCLUSIONS

Our study showed increased PGE2 production and mRNA expression of EP1 and EP2 receptors in the bladder in patients with interstitial cystitis and Hunner lesions. Further studies are warranted to explore the pathophysiological and therapeutic implications.

Pathological significance and prognostic role of microvessel density, evaluated using CD31, CD34, and CD105 in prostate cancer patients after radical prostatectomy with neoadjuvant therapy

BACKGROUND

Neoadjuvant hormonal therapy (NHT) is performed to improve the outcome in organ-confined prostate cancer. However, there is little information regarding the relationship between angiogenesis and NHT. The aim of this study was to identify a suitable method to evaluate the angiogenic status of tissue, and to determine the prognostic value of this method for biochemical recurrence in patients who had undergone radical prostatectomy after NHT.

METHODS

We analyzed 108 formalin-fixed specimens from patients treated by radical prostatectomy. NHT was administered in 48 patients (52.9%) and 60 patients who had a similar Gleason score and pT stage were selected as a non-NHT treated control group. Microvessel density (MVD) was measured using anti-CD31, anti-CD34, and anti-CD105 antibodies. The expressions of vascular endothelial growth factor (VEGF)-A and thrombospondin (TSP)-1 were also evaluated by immunohistochemistry. The prognostic value of CD31-, CD34-, and CD105-MVD for biochemical recurrence was investigated.

RESULTS

The mean/SD of CD105-MVD in the NHT group (13.3/4.7) was significantly (P < 0.001) lower than that in the non-NHT group (125.8/7.3). In the NHT group, CD105-MVD was associated with pT stage and it was positively correlated with VEGF-A expression (r = 0.56, P < 0.001) and negatively correlated with TSP-1 expression (r = 0.42, P = 0.003). CD105-MVD was identified as a significant predictor of biochemical recurrence (BCR) in patients treated with NHT (log rank test, P < 0.001). Although CD31- and CD34-MVD were significantly associated with pT stage or Gleason score in non-NHT group, they were not associated with pathological features and BCR in NHT group.

CONCLUSIONS

Our results indicate that CD105-MVD reflects the angiogenic conditions in prostate cancer tissues treated with NHT. CD105-MVD was also identified as a significant and independent predictor of biochemical recurrence in prostate cancer patients who underwent radical prostatectomy with NHT.

Inflammatory lymphangiogenesis in postpartum breast tissue remodeling

Like many cancers, mammary carcinomas use lymphatic vessels to disseminate, and numerous clinical and experimental studies have documented a strong correlation between peritumoral lymphangiogenesis and tumor dissemination. At the same time, many other factors can affect the incidence, invasiveness, and mortality of breast cancer, including lactation history. Although lactation reduces overall cancer risk, patients diagnosed within 5 years of pregnancy have an increased incidence of metastatic disease. In this issue of the JCI, Lyons and colleagues demonstrate that postpartum breast tissue remodeling during involution coincides with inflammatory lymphangiogenesis. In mouse models, cyclooxygenase-2 (COX-2) inhibition during involution reduced the risk of cancer metastasis and correlated with decreased lymphangiogenesis. In addition to lymphangiogenesis, COX-2 inhibition reduces many of the immune-suppressive features of the tumor microenvironment, including development of myeloid-derived suppressor cells and regulatory T cells; therefore, these results support the notion that inhibiting COX-2 during lactation weaning may lessen the incidence of breast cancer metastasis.