Paweł Uruski

Effect of allopurinol on blood pressure and aortic compliance in hypertensive patients

Abstract Background. Arterial hypertension is commonly associated with hyperuricemia. Several studies have shown that allopurinol reduces arterial blood pressure in animal models and in adolescent patients with newly diagnosed hypertension. Moreover, allopurinol has shown beneficial effects on endothelial function and arterial wave reflection in contrast to uricosuric agents. Antihypertensive drugs produce different effects on serum uric acid levels. Objective. The aim of the study was to evaluate the influence of allopurinol on blood pressure and aortic compliance in patients with arterial hypertension depending on hypotensive therapy with angiotensin-converting enzyme inhibitor (ACE-I) or thiazide diuretic, hypotensive drugs with distinct effects on serum uric acid levels and conversely, a positive influence on pulse wave velocity (PWV) in the aorta. Material and Methods. Sixty-six patients aged 25–70 (mean age 46.17 ± 10.89) with mild and moderate arterial hypertension diagnosed on the basis of office blood pressure, were studied. They were randomized to antihypertensive therapy on either perindopril (n = 35) or hydrochlorothiazide (n = 31). After 8 weeks of antihypertensive therapy, 150 mg of allopurinol daily was added for the next 8 weeks. Measurement of the serum uric acid level, PWV and 24-h ambulatory blood pressure monitoring (ABPM) were performed at baseline, after 8 weeks antihypertensive therapy and again after the final 8 weeks with the additional allopurinol. Results. No significant changes in systolic (SBP) and diastolic blood pressure (DBP) or ABPM were observed after allopurinol treatment in either of the subgroups receiving ACE-I or thiazide-based antihypertensive therapy. The mean PWV decreased from 10.7 ± 1.4 m/s to 10.0 ± 1.2 m/s (p = 0.00008) in the ACE-I-based therapy subgroup and from 11.5 ±1.7 m/s to 10.4 ± 1.5 m/s (p = 0.00002) in the thiazide-based therapy subgroup after treatment with allopurinol. However, significant correlations were found between PWV changes and the basic PWV (r = −0.52; p < 0.001) or SBP changes (r = 0.29; p < 0.019) after allopurinol treatment. Conclusions. Allopurinol does not produce additional antihypertensive effects in patients with treated arterial hypertension. Allopurinol increases aortic compliance independently of ACE-I or thiazide-based, antihypertensive therapy. However, this effect is significantly dependent on the initial PWV in the aorta and on SBP changes during allopurinol therapy.

Ovarian cancer-derived ascitic fluids induce a senescence-dependent pro-cancerogenic phenotype in normal peritoneal mesothelial cells

PurposeAfter the seeding ovarian cancer cells into the peritoneal cavity, ascitic fluid creates a microenvironment in which these cells can survive and disseminate. The exact nature of the interactions between malignant ascitic fluids and peritoneal mesothelial cells (HPMCs) in ovarian cancer progression has so far remained elusive. Here we assessed whether malignant ascitic fluids may promote the senescence of HPMCs and, by doing so, enhance the acquisition of their pro-cancerogenic phenotype.MethodsPrimary omentum-derived HPMCs, ovarian cancer-derived cell lines (A2780, OVCAR-3, SKOV-3), malignant ascitic fluids and benign ascitic fluids from non-cancerous patients were used in this study. Ovarian cancer cell proliferation, as well as HPMC proliferation and senescence, were determined using flow cytometry and β-galactosidase assays, respectively. Ovarian cancer cell migration was quantified using a Transwell assay. The concentrations of soluble agents in ascitic fluids, conditioned media and cell lysates were measured using DuoSet® Immunoassay Development kits.ResultsWe found that HPMCs, when exposed to malignant ascitic fluids, exhibited decreased proliferation and increased senescence rates. The malignant ascitic fluids were found to contain elevated levels of HGF, TGF-β1 and GRO-1, of which HGF and GRO-1 were able to induce senescence in HPMCs. We also found that HPMCs subjected to malignant ascitic fluids or exogenously added HGF and GRO-1 stimulated ovarian cancer cell progression, which was manifested by an increased production of HA (adhesion), uPA (proliferation), IL-8 and MCP-1 (migration).ConclusionOur results indicate that malignant ascitic fluids may contribute to ovarian cancer progression by accelerating the senescence of HPMCs.

Higher risk of microvascular complications in smokers with type 1 diabetes despite intensive insulin therapy.

AIM The aim of the study was to evaluate the relationship between smoking status and the incidence of microvascular complications in patients with type 1 diabetes (DM1), treated with intensive functional insulin therapy (IFIT) from the onset of the disease. METHODS 81 participants (51 men, 30 women) of Poznan Prospective Study (PoProStu) with mean age of 34.0 ± 6.4 years were included in this analysis. Patients were observed for 10.0 ± 1.5 years. Evaluation of microvascular complications of diabetes, such as retinopathy, diabetic kidney disease and neuropathy was performed. Patients were divided into two groups depending on the smoking status: smokers and non-smokers. RESULTS In the group of smokers (n=36) in comparison with patients who had never smoked (n=45) any microangiopathy (58.3% vs 33.3%, p=0.02), retinopathy (44.4% vs 20%, p=0.02), diabetic kidney disease (47.2% vs 24.4%, p=0.03) and neuropathy (25% vs 4.4%, p=0.02) were found more often. A significant relationship, adjusted for age, sex, duration of diabetes, presence of hypertension and HbA1c between smoking and neuropathy and retinopathy was revealed [OR 10.16 (95%CI 1.59-64.95); p=0.01 and OR 3.50 (95%CI 1.01-12.12); p=0.04, respectively]. CONCLUSION The results show that in patients with DM1, there is a strong relationship between smoking and the diabetic microvascular complications, especially with neuropathy, despite treatment from the initial diagnosis with intensive insulin therapy.

Senescent peritoneal mesothelium creates a niche for ovarian cancer metastases

Although both incidence and aggressiveness of ovarian malignancy rise with age, the exact reason for this tendency, in particular the contribution of senescent cells, remains elusive. In this project we found that the patient’s age determines the frequency of intraperitoneal metastases of ovarian cancer. Moreover, we documented that senescent human peritoneal mesothelial cells (HPMCs) stimulate proliferation, migration and invasion of ovarian cancer cells in vitro, and that this effect is related to both the activity of soluble agents released to the environment by these cells and direct cell-cell contact. The panel of mediators of the pro-cancerous activity of senescent HPMCs appeared to be cancer cell line-specific. The growth of tumors in a mouse peritoneal cavity was intensified when the cancer cells were co-injected together with senescent HPMCs. This effect was reversible when the senescence of HPMCs was slowed down by the neutralization of p38 MAPK. The analysis of lesions excised from the peritoneum of patients with ovarian cancer showed the abundance of senescent HPMCs in close proximity to the cancerous tissue. Collectively, our findings indicate that senescent HPMCs which accumulate in the peritoneum in vivo may create a metastatic niche facilitating intraperitoneal expansion of ovarian malignancy.

Oxidative stress contributes to hepatocyte growth factor-dependent pro-senescence activity of ovarian cancer cells

Abstract The cancer‐promoting activity of senescent peritoneal mesothelial cells (HPMCs) has already been well evidenced both in vitro and in vivo. Here we sought to determine if ovarian cancer cells may activate senescence in HPMCs. The study showed that conditioned medium (CM) from ovarian cancer cells (OVCAR‐3, SKOV‐3, A2780) inhibited growth and promoted the development of senescence phenotype (increased SA‐&bgr;‐Gal, &ggr;‐H2A.X, 53BP1, and decreased Cx43) in HPMCs. An analysis of tumors isolated from the peritoneum of patients with ovarian cancer revealed an abundance of senescent HPMCs in proximity to cancerous tissue. The presence of senescent HPMCs was incidental when fragments of peritoneum free from cancer were evaluated. An analysis of the cells’ secretome followed by intervention studies with exogenous proteins and neutralizing antibodies revealed hepatocyte growth factor (HGF) as the mediator of the pro‐senescence impact of the cancer cells. The activity of cancerous CM and HGF was associated with an induction of mitochondrial oxidative stress. Signaling pathways involved in the senescence of HPMCs elicited by the cancer‐derived CM and HGF included p38 MAPK, AKT and NF‐&kgr;B. HPMCs that senesced prematurely in response to the cancer‐derived CM promoted adhesion of ovarian cancer cells, however this effect was effectively prevented by the cell protection against oxidative stress. Collectively, our findings indicate that ovarian cancer cells can elicit HGF‐dependent senescence in HPMCs, which may contribute to the formation of a metastatic niche for these cells within the peritoneal cavity. Graphical abstract Figure. No caption available. HighlightsConditioned medium (CM) from ovarian cancer cells induces senescence in HPMCs.Hepatocyte growth factor (HGF) mediates the pro‐senescence activity of cancerous CM.Activity of cancerous CM/HGF is associated with the induction of oxidative stress.Signaling pathways underlying activity of CM/HGF include AKT, p38 MAPK and NF‐&kgr;B.HPMCs senesced in response to cancerous CM/HGF promote ovarian cancer cell adhesion.

Serum from Varicose Patients Induces Senescence-Related Dysfunction of Vascular Endothelium Generating Local and Systemic Proinflammatory Conditions

Although the role of endothelium in varicose vein development is indisputable, the effect of the pathology on biological properties of endothelial cells remains unclear. Here we examined if the presence of varicose veins affects senescence of endothelial cells (HUVECs) and, if so, what will be the local and systemic outcome of this effect. Experiments showed that HUVECs subjected to serum from varicose patients display improved proliferation, increased expression of senescence marker, SA-β-Gal, and increased generation of reactive oxygen species (ROS), as compared with serum from healthy donors. Both increased SA-β-Gal activity and ROS release were mediated by TGF-β1, the concentration of which in varicose serum was elevated and the activity of which in vitro was prevented using specific neutralizing antibody. Senescent HUVECs exposed to varicose serum generated increased amounts of ICAM-1, VCAM-1, P-selectin, uPA, PAI-1, and ET-1. Direct comparison of sera from varicose and healthy donors showed that pathological serum contained increased level of ICAM-1, VCAM-1, P-selectin, uPA, and ET-1. Calendar age of healthy subjects correlated positively with serum uPA and negatively with P-selectin. Age of varicose patients correlated positively with ICAM-1, VCAM-1, and ET-1. Collectively, our findings indicate that the presence of varicose veins causes a senescence-related dysfunction of vascular endothelium, which leads to the development of local and systemic proinflammatory environment.

Biochemical composition of malignant ascites determines high aggressiveness of undifferentiated ovarian tumors

Although undifferentiated tumors are the most lethal among all ovarian cancer histotypes, the exact reasons for this situation are unclear. This report was aimed at investigating whether the high aggressiveness of undifferentiated ovarian cancer may be associated with a biochemical composition of malignant ascites accumulating in the peritoneal cavity. We analyzed ascites from patients with undifferentiated, high-grade serous, endometrioid and clear-cell ovarian cancers, and from non-cancerous patients with respect to a group of soluble agents involved in cancer cell progression. Moreover, the effect of these fluids on proliferation and migration of ovarian cancer cells (A2780, OVCAR-3 and SKOV-3) was evaluated. The study showed that the level of all tested proteins in malignant ascites was higher than in the benign fluids. Concentration of 9/11 agents (CCL2, CXCL1, CXCL5, CXCL8, CXCL12, HGF, PAI-1, TGF-β1 and VEGF) was the greatest in the fluids from undifferentiated cancer, while the level of remaining 2 (IL-6 and uPA) was the highest in ascites from serous carcinoma. Proliferation of cancer cells was the most effective when they were subjected to ascites from patients with undifferentiated and serous cancer, whereas the migration was the highest in the case of undifferentiated tumors. Our findings indicate that the aggressiveness of undifferentiated ovarian tumors may be associated with the composition of malignant ascites, in particular the concentration of specific proinflammatory, cancer-promoting agents.

The peritoneal “soil” for a cancerous “seed”: a comprehensive review of the pathogenesis of intraperitoneal cancer metastases

Various types of tumors, particularly those originating from the ovary and gastrointestinal tract, display a strong predilection for the peritoneal cavity as the site of metastasis. The intraperitoneal spread of a malignancy is orchestrated by a reciprocal interplay between invading cancer cells and resident normal peritoneal cells. In this review, we address the current state-of-art regarding colonization of the peritoneal cavity by ovarian, colorectal, pancreatic, and gastric tumors. Particular attention is paid to the pro-tumoral role of various kinds of peritoneal cells, including mesothelial cells, fibroblasts, adipocytes, macrophages, the vascular endothelium, and hospicells. Anatomo-histological considerations on the pro-metastatic environment of the peritoneal cavity are presented in the broader context of organ-specific development of distal metastases in accordance with Paget’s “seed and soil” theory of tumorigenesis. The activity of normal peritoneal cells during pivotal elements of cancer progression, i.e., adhesion, migration, invasion, proliferation, EMT, and angiogenesis, is discussed from the perspective of well-defined general knowledge on a hospitable tumor microenvironment created by the cellular elements of reactive stroma, such as cancer-associated fibroblasts and macrophages. Finally, the paper addresses the unique features of the peritoneal cavity that predispose this body compartment to be a niche for cancer metastases, presents issues that are topics of an ongoing debate, and points to areas that still require further in-depth investigations.

The protective activity of mesothelial cells against peritoneal growth of gastrointestinal tumors: The role of soluble ICAM-1

In this project we examined how the presence of human peritoneal mesothelial cells (HPMCs) modifies (supports or inhibits) colorectal and pancreatic cancer cell progression in mice peritoneal cavity. Experiments were performed using primary, omentum-derived HPMCs, commercially available colorectal (SW-480) and pancreatic (PSN-1) cancer cells, and immunocompromised SCID mice. Tumor growth within the peritoneal cavity was monitored using bioluminescence. Adhesion of the cancer cells to HPMCs was examined using a fluorescence-based method, while the incidence of apoptosis was quantified using flow cytometry. Experiments showed that SW480 and PSN-1 cells formed tumors in vivo at higher efficiency when they were injected alone than in the presence of HPMCs. In vitro investigations confirmed that firm adhesion of SW480 and PSN-1 cells to HPMCs is mediated by interactions between ICAM-1 and CD43. They also revealed that IL-6 and TNFα up-regulate the expression of cell-bound ICAM-1 and the secretion of soluble ICAM-1 (sICAM-1). The basal release of sICAM-1 by HPMCs positively correlated with the expression of the cell-bound molecule. sICAM-1 inhibited dose-dependently the adhesion of SW480 and PSN-1 cells to HPMCs. Cancer cells that did not adhere to HPMCs displayed increased activity of caspase-3 and -9, increased incidence of apoptosis, and an inability to re-adhesion, as compared with their intact counterparts not exposed to sICAM-1. Our findings indicate that under certain conditions HPMCs are capable of inhibiting growth of gastrointestinal tumors in a mechanism involving the anti-adhesive capabilities of sICAM-1.

Procancerogenic activity of senescent cells: A case of the peritoneal mesothelium

Human peritoneal mesothelial cells belong to a narrow group of somatic cells in which both the triggers and the mechanisms of senescence have already been well defined. Importantly, senescent mesothelial cells have been found in the peritoneal cavity in vivo. From a clinical point of view, peritoneal mesothelial cells have been recognized as playing a critical role in the intraperitoneal development of tumor metastases. The pro-cancerogenic behavior of mesothelial cells is even more pronounced when the cells exhaust their proliferative capacity and become senescent. In this review, we summarize the current state of art regarding the contribution of peritoneal mesothelial cells in the progression of ovarian, colorectal, and pancreatic carcinomas, with particular attention paid to the cancer-promoting activity of their senescent counterparts. Moreover, we delineate the mechanisms, mediators, and signaling pathways that are engaged by the senescent mesothelial cells to support such vital elements of cancer progression as adhesion, proliferation, migration, invasion, epithelial-mesenchymal transition, and angiogenesis. Finally, we discuss the experimental evidence regarding both natural and synthetic compounds that may either prevent or restrict cancer development by delaying senescence of mesothelial cells.