Different types of tumor microvessels in stageⅠ-ⅢA squamous cell lung cancer and their clinical significance

BACKGROUND Lung cancer(LC)is the leading cause of morbidity and mortality among malignant neoplasms.Improving the diagnosis and treatment of LC remains an urgent task of modern oncology.Previously,we established that in gastric,breast and cervical cancer,tumor microvessels(MVs)differ in morphology and have different prognostic significance.The connection between different types of tumor MVs and the progression of LC is not well understood.AIM To evaluate the morphological features and clinical significance of tumor MVs in lung squamous cell carcinoma(LUSC).METHODS A single-center retrospective cohort study examined medical records and archival paraffin blocks of 62 and 180 patients with stage I-IIIA LUSC in the training and main cohorts,respectively.All patients underwent radical surgery(R0)at the Orenburg Regional Cancer Clinic from May/20/2009 to December/14/2021.Tumor sections were routinely processed,and routine Mayer's hematoxylin and eosin staining and immunohistochemical staining for cluster of differentiation 34(CD34),podoplanin,Snail and hypoxia-inducible factor-1 alpha were performed.The morphological features of different types of tumor MVs,tumor parenchyma and stroma were studied according to clinicopathological characteristics and LUSC prognosis.Statistical analysis was performed using Statistica 10.0 software.Univariate and multivariate logistic regression analyses were performed to identify potential risk factors for LUSC metastasis to regional lymph nodes(RLNs)and disease recurrence.Receiver operating characteristic curves were constructed to discriminate between patients with and without metastases in RLNs and those with and without disease recurrence.The effectiveness of the predictive models was assessed by the area under the curve.Survival was analyzed using the Kaplan-Meier method.The log-rank test was used to compare survival curves between patient subgroups.A value of P<0.05 was considered to indicate statistical significance.RESULTS Depending on the morphology,we classified tumor vessels into the following types:normal MVs,dilated capillaries(DCs),atypical DCs,DCs with weak expression of CD34,"contact-type"DCs,structures with partial endothelial linings,capillaries in the tumor solid component and lymphatic vessels in lymphoid and polymorphocellular infiltrates.We also evaluated the presence of loose,fine fibrous connective tissue(LFFCT)and retraction clefts in the tumor stroma,tumor spread into the alveolar air spaces(AASs)and fragmentation of the tumor solid component.According to multivariate analysis,the independent predictors of LUSC metastasis in RLNs were central tumor location(P<0.00001),the presence of retraction clefts(P=0.003),capillaries in the tumor solid component(P=0.023)and fragmentation in the tumor solid component(P=0.009),whereas the independent predictors of LUSC recurrence were tumor grade 3(G3)(P=0.001),stage N2(P=0.016),the presence of LFFCT in the tumor stroma(P<0.00001),fragmentation of the tumor solid component(P=0.0001),and the absence of tumor spread through the AASs(P=0.0083).CONCLUSION The results obtained confirm the correctness of our previously proposed classification of different types of tumor vessels and may contribute to improving the diagnosis and treatment of LUSC.

Issues of origin,morphology and clinical significance of tumor microvessels in gastric cancer

Gastric cancer(GC)remains a serious oncological problem,ranking third in the structure of mortality from malignant neoplasms.Improving treatment outcomes for this pathology largely depends on understanding the pathogenesis and biological characteristics of GC,including the identification and characterization of diagnostic,prognostic,predictive,and therapeutic biomarkers.It is known that the main cause of death from malignant neoplasms and GC,in particular,is tumor metastasis.Given that angiogenesis is a critical process for tumor growth and metastasis,it is now considered an important marker of disease prognosis and sensitivity to anticancer therapy.In the presented review,modern concepts of the mechanisms of tumor vessel formation and the peculiarities of their morphology are considered;data on numerous factors influencing the formation of tumor microvessels and their role in GC progression are summarized;and various approaches to the classification of tumor vessels,as well as the methods for assessing angiogenesis activity in a tumor,are highlighted.Here,results from studies on the prognostic and predictive significance of tumor microvessels in GC are also discussed,and a new classification of tumor microvessels in GC,based on their morphology and clinical significance,is proposed for consideration.

Changes of 5-hydroxytryptamine and dopamine contents in brain microvessels and the influence on cerebral edema at early stage of brain injury

The contents of 5-hydroxytryptamine(5-HT)and dopamine(DA) in the brain microvessels(BMVs) at the early stage of rat brain injury were measured by using high performance liquid chromatography with electrochemical detector(HPLC-ECD) and the influence of the

Research on the prognosis of different types of microvessels in bladder transitional cell carcinoma

BACKGROUND At present,there is controversy on the role of microvessel density(MVD)in tumors as a prognostic indicator of bladder transitional cell carcinoma(BTCC).However,the MVD in tumors is simply classified based on the expression of several different vascular markers,which has not been related to analytical research on the prognosis of patients with BTCC.AIM To explore the classification of blood vessels in tumors and studied the relationship between MVD and the prognosis of patients with BTCC.METHODS The tissue mass was detected by tissue microarray and immunohistochemical analysis with monoclonal antibodies against CD31,CD34,CD105,and vascular smooth muscle actin to investigate the MVD in BTCC.The measurement data are expressed as the mean±SD.The difference between the groups was analyzed by the t-test,the counting data were analyzed byχ2 test.The Kaplan-Meier survival curve was estimated by the product-limit method.The log-rank time-series test was employed to compare the tumor-free survival curves.RESULTS The MVD was closely related to the pathological grade,invasive depth,and prognosis of BTCC.Significant differences were found between grade I and grade II,grade II and grade III,superficial and invasive type,and the tumor-free survival group and the recurrence or metastasis group(P<0.01).Multivariate analysis showed that undifferentiated MVD was an independent prognostic factor for patient survival time.An inverse correlation between undifferentiated tumor MVD and differentiated tumor MVD in BTCC was also shown.CONCLUSION The classification of blood vessels in BTCC could act as an important prognostic indicator and may also be of great significance in the treatment of cancer.

An experimental study of early anastomosis of injured microvessels of maxillofacial region in dogs

This study was designed to evaluate whether the microvascularanastomosis of small arteries and veins in the wound area was possible after gun-shot wound was inflicted to the maxillofacial region of a dog.It was found thatsmall vessels could be connected with subsequent patency of their lumen if theoperation was performed on the 3rd day after the debridment of the gunshotWound,which provides a basis for microvascular anastomosis to repairmaxillofacial defect due to gunshot wound with free vascularized flap grafting.Inaddition the best time to have a defect repaired and the healing features of thewounds after vascular anastomosis are discussed.

Relationship between Vasodilation Effect of Aniso-damine and Endothelial Target for Acetylcholine on Microvessels in Rat

Objective To study the effects of anisodamine on microvessels and its relationship with endothelium target for acetylcholine (ETA). Methods Norepinephrine precontracted mesen-teric vascular beds in rat were used to determine changes of tension of vessels in response to anisodamine after removal of endotlielium, coincubated with L- NAME, nitric oxide synthase (NOS ) inhibitor, in-domethacin,cyclo-oxygenase inhibitor and glibenclamide, ATP-dependent K+ channels (KATP) inhibitor. Results Anisodamine produced a vasodilatian effect on mesenteric vascular beds,which was remarkably inhibited after removal of endothelium (P<0. 01). The vasodilation effect of anisodamine was also significantly inhibited after coincubated with indometliacin (1 μmol/U) ,NG-nitro-L-arginine methyl ester (L-NAME,100 μmol/L) and glibenclamide (1 /μmol/L, P< 0. 01, vs control). Conclusion The vasodilation effect of anisodamine on microvessels was mediated by ETA. This is related to prostacyclin,endothelium derived relaxing factor (EDRF) and KATP besides M, a-receptor on vascular smooth muscle cell(VSMC) and calcium-antagonistic effects.

Expression and significance of pigment epithelium-derived factor and vascular endothelial growth factor in colorectal adenoma and cancer

BACKGROUND The incidence and mortality of colorectal cancer(CRC)are among the highest in the world,and its occurrence and development are closely related to tumor neovascularization.When the balance between pigment epithelium-derived factors(PEDF)that inhibit angiogenesis and vascular endothelial growth factors(VEGF)that stimulate angiogenesis is broken,angiogenesis is out of control,resulting in tumor development.Therefore,it is very necessary to find more therapeutic targets for CRC for early intervention and later treatment.AIM To investigate the expression and significance of PEDF,VEGF,and CD31-stained microvessel density values(CD31-MVD)in normal colorectal mucosa,adenoma,and CRC.METHODS In this case-control study,we collected archived wax blocks of specimens from the Digestive Endoscopy Center and the General Surgery Department of Chengdu Second People's Hospital from April 2022 to October 2022.Fifty cases of specimen wax blocks were selected as normal intestinal mucosa confirmed by electronic colonoscopy and concurrent biopsy(normal control group),50 cases of specimen wax blocks were selected as colorectal adenoma confirmed by electronic colonoscopy and pathological biopsy(adenoma group),and 50 cases of specimen wax blocks were selected as CRC confirmed by postoperative pathological biopsy after inpatient operation of general surgery(CRC group).An immunohistochemical staining experiment was carried out to detect PEDF and VEGF expression in three groups of specimens,analyze their differences,study the relationship between the two and clinicopathological factors in CRC group,record CD31-MVD in the three groups,and analyze the correlation of PEDF,VEGF,and CD31-MVD in the colorectal adenoma group and the CRC group.The F test or adjusted F test is used to analyze measurement data statistically.Kruskal-Wallis rank sum test was used between groups for ranked data.The chi-square test,adjusted chi-square test,or Fisher's exact test were used to compare the rates between groups.All differences between groups were compared using the Bonferroni method for multiple comparisons.Spearman correlation analysis was used to test the correlation of the data.The test level(α)was 0.05,and a two-sided P<0.05 was considered statistically significant.RESULTS The positive expression rate and expression intensity of PEDF were gradually decreased in the normal control group,adenoma group,and CRC group(100%vs 78%vs 50%,χ^(2)=34.430,P<0.001;++~++vs+~++vs-~+,H=94.059,P<0.001),while VEGF increased gradually(0%vs 68%vs 96%,χ^(2)=98.35,P<0.001;-vs-~+vs++~+++,H=107.734,P<0.001).In the CRC group,the positive expression rate of PEDF decreased with the increase of differen-tiation degree,invasion depth,lymph node metastasis,distant metastasis,and TNM stage(χ^(2)=20.513,4.160,5.128,6.349,5.128,P<0.05);the high expression rate of VEGF was the opposite(χ^(2)=10.317,13.134,17.643,21.844,17.643,P<0.05).In the colorectal adenoma group,the expression intensity of PEDF correlated negatively with CD31-MVD(r=-0.601,P<0.001),whereas VEGF was not significantly different(r=0.258,P=0.07).In the CRC group,the expression intensity of PEDF correlated negatively with the expression intensity of CD31-MVD and VEGF(r=-0.297,P<0.05;r=-0.548,P<0.05),while VEGF expression intensity was positively related to CD31-MVD(r=0.421,P=0.002).CONCLUSION It is possible that PEDF can be used as a new treatment and prevention target for CRC by upregulating the expression of PEDF while inhibiting the expression of VEGF.

Microvascular alterations of the ocular surface and retina in connective tissue disease-related interstitial lung disease

AIM:To examine the disparities in macular retinal vascular density between individuals with connective tissue disease-related interstitial lung disease(CTD-ILD)and healthy controls(HCs)by optical coherence tomography angiography(OCTA)and to investigate the changes in microvascular density in abnormal eyes.METHODS:For a retrospective case-control study,a total of 16 patients(32 eyes)diagnosed with CTD-ILD were selected as the ILD group.The 16 healthy volunteers with 32 eyes,matched in terms of age and sex with the patients,were recruited as control group.The macular retina’s superficial retinal layer(SRL)and deep retinal layer(DRL)were examined and scanned using OCTA in each individual eye.The densities of retinal microvascular(MIR),macrovascular(MAR),and total microvascular(TMI)were calculated and compared.Changes in retinal vascular density in the macular region were analyzed using three different segmentation methods:central annuli segmentation method(C1-C6),hemispheric segmentation method[uperior right(SR),superior left(SL),inferior left(IL),and inferior right(IR)],and Early Treatment Diabetic Retinopathy Study(ETDRS)methods[superior(S),inferior(I),left(L),and right(R)].The data were analyzed using Version 9.0 of GraphPad prism and Pearson analysis.RESULTS:The OCTA data demonstrated a statistically significant difference(P<0.05)in macular retinal microvessel density between the two groups.Specifically,in the SRL and DRL analyses,the ILD group exhibited significantly lower surface density of MIR and TMI compared to the HCs group(P<0.05).Furthermore,using the hemispheric segmentation method,the ILD group showed notable reductions in SL,SR,and IL in the superficial retina(P<0.05),as well as marked decreases in SL and IR in the deep retina(P<0.05).Similarly,when employing the ETDRS method,the ILD group displayed substantial drops in superficial retinal S and I(P<0.05),along with notable reductions in deep retinal L,I,and R(P<0.05).In the central annuli segmentation method,the ILD group exhibited a significant decrease in the superficial retinal C2-4 region(P<0.05),whereas the deep retina showed a notable reduction in the C3-5 region(P<0.05).Additionally,there was an observed higher positive likelihood ratio in the superficial SR region and deep MIR.Furthermore,there was a negative correlation between conjunctival vascular density and both deep and superficial retinal TMI(P<0.001).CONCLUSION:Patients with CTD-ILD exhibits a significantly higher conjunctival vascular density compared to the HCs group.Conversely,their fundus retinal microvascular density is significantly lower.Furthermore,CTD-ILD patients display notably lower superficial and deep retinal vascular density in comparison to the HCs group.The inverse correlation between conjunctival vascular density and both superficial and deep retinal TMI suggests that detecting subtle changes in ocular microcirculation could potentially serve as an early diagnostic indicator for connective tissue diseases,thereby enhancing disease management.

Quantitative evaluation of colorectal tumour vasculature using contrast-enhanced ultrasound:Correlation with angiogenesis and prognostic significance

BACKGROUND Ultrasound is a vital tool for the diagnosis and management of colorectal cancer(CRC).Contrast-enhanced ultrasound(CEUS)is a non-invasive,safe,and cost-effective method for evaluating tumour blood vessels,that play a crucial role in tumour growth and progression.AIM To explore CEUS’s role in the quantitative evaluation of CRC blood vessels and their correlation with angiogenesis markers and prognosis.METHODS This study prospectively enrolled 100 patients with CRC confirmed by histo-pathology.All patients received preoperative CEUS examinations.Quantitative parameters,such as peak intensity(PI),time to peak(TTP),and area under the curve(AUC),were derived from time-intensity curve(TIC)analysis.Tumour tissue samples were obtained during surgery and examined immunohistochem-ically to assess the expression of angiogenesis markers,including vascular endo-thelial growth factor(VEGF)and microvessel density(MVD).The correlation between CEUS parameters,angiogenesis markers,and clinicopathological features was evaluated using appropriate statistical tests.RESULTS Quantitative CEUS parameters(PI,TTP,and AUC)showed significant correlations with VEGF expression(P<0.001)and MVD(P<0.001),indicating a strong link between tumour blood vessels and angiogenesis.Increased PI,reduced TTP,and expanded AUC values were significantly related to higher tumour stage(P<0.001),lymph node metastasis(P<0.001),and distant metastasis(P<0.001).Furthermore,these parameters were recognized as independent predictors of overall survival and disease-free survival in multivariate analysis(P<0.001).CONCLUSION CEUS has a high potential in guiding treatment planning and predicting patient outcomes.However,more com-prehensive,multicentre studies are required to validate the clinical utility of CEUS in CRC management.

Microvessel density in patients with gastrointestinal stromal tumors:A systematic review and meta-analysis

BACKGROUND Gastrointestinal stromal tumors(GISTs)are considered the most common mesenchymal tumors of the gastrointestinal tract.Microvessel density(MVD)constitutes a direct method of vascularity quantification and has been associated with survival rates in multiple malignancies.AIM To appraise the effect of MVD on the survival of patients with GIST.METHODS This study adhered to Systematic reviews and Meta-Analyses guidelines and the Cochrane Handbook for Systematic Reviews of Interventions.Electronic scholar databases and grey literature repositories were systematically screened.The Fixed Effects or Random Effects models were used according to the Cochran Q test.RESULTS In total,6 eligible studies were identified.The pooled hazard ratio(HR)for disease free survival(DFS)was 8.52(95%CI:1.69-42.84,P=0.009).The odds ratios of disease-free survival between high and low MVD groups at 12 and 60 mo did not reach statistical significance.Significant superiority of the low MVD group in terms of DFS was documented at 36 and 120 mo(OR:8.46,P<0.0001 and OR:22.71,P=0.0003,respectively)as well as at metastases rate(OR:0.11,P=0.0003).CONCLUSION MVD significantly correlates with the HR of DFS and overall survival rates at 36 and 120 mo.Further prospective studies of higher methodological quality are required.

Role of P2X_7 receptors in the development of diabetic retinopathy

The P2X7 receptor is one of the members of the family of purinoceptors which are ligand-gated membrane ion channels activated by extracellular adenosine 5'-triphosphate. A unique feature of the P2X7 receptor is that its activation can result in the formation of large plasma membrane pores that allow not only the flux of ions but also of hydrophilic molecules of up to 900 Da. Recent studies indicate that P2X7-mediated signaling can trigger apoptotic cell death after ischemia and during the course of certain neurodegenerative disorders. Expression of the P2X7 receptor has been demonstrated in most types of cells in the retina. This purinoceptor mediates the contraction of pericytes and regulates the spatial and temporal dynamics of the vasomotor response through cell-to-cell electrotonic transmission within the microvascular networks. Of potential clinical significance, investigators have found that diabetes markedly boosts the vulnerability of retinal microvessels to the lethal effect of P2X7 receptor activation. This purinergic vasotoxicity may result in reduced retinal blood flow and disrupted vascular function in the diabetic retina. With recent reports indicating an association between P2X7 receptor activation and inflammatory cytokine expression in the retina, this receptor may also exacerbate the development of diabetic retinopathy by a mechanism involving inflammation.

Expression of Angiopoietin-2 and Vascular Endothelial Growth Factor in Oral Squamous Cell Carcinoma and Its Significance

Objective： To investigate the expression of angiopoietin-2 （Ang-2） and vascular endothelialcell growth factor （VEGF） in oral squamous cell carcinoma （OSCC） and their correlations with clinicopathologic parameters, angiogenesis and vessel maturation of OSCC. Methods： The expression of Ang-2 and VEGF was detected in 41 speciments of human OSCC, 30 adjacent noncancerous oral tissues and 10 specimens of normal oral mucosa by conventional immumohistochemistry. Microvessel density （MVD） and vessel maturation index （VMI） were also assessed by double-labelling immumohistochemistry staining against CD34, a marker of pan-endothelial cells, and that against alpha-smooth muscle actin （α-SMA）, a marker of mural cells （pericytes/smooth muscle cells）. Results： The positive expression rate of Ang-2 and VEGF in 41 OSCC tissues was 51.22% and 63.42%, respectively. The expression of Ang-2 and VEGF was significantly higher in OSCC than in adjacent noncancerous oral tissues （all P〈0.05） and normal oral mucosa （all P〈0.05）. In the clinicopathologic parameters, the Ang-2 expression was closely correlated with tumor lymph node metastasis （P〈0.01） and the VEGF expression was correlated with tumor differentiated degree （P〈0.05）, but there was no significant correlation among the Ang-2 and VEGF expression and patients＇ sex, age and TNM stages （all P〉0.05）. The MVD of OSCC positive for both Ang-2 and VEGF was significantly higher than that of OSCC negative for both Ang-2 and VEGF （P〈0.05）. The VMI of OSCC positive for Ang-2 was significantly lower than that of OSCC negative for Ang-2 （P〈0.05）. When Ang-2 expression was combined with the staus of VEGF expression, MVD of OSCC positive for both Ang-2 and VEGF was the highest （51.08±2.99） as compared with that of other status in patient with OSCC （all P〈0.05）. Conclusion： The overexpression of Ang-2 and VEGF may play a crucial role in the development of OSCC. They are closely associated with angiogenesis and vessel maturation of tumor.

Expression of endothelial nitric oxide synthase and vascular endothelial growth factor in association with neovascularization in human primary astrocytoma

Objective: To investigate the relationship between the expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) and angiogenesis in primary astrocytoma. Methods: Thirty-seven primary astrocytomas and 4 astrocytic hyperplasia samples were collected and divided into three groups according to histological grade. The expression of eNOS, VEGF and factorⅧ related antigen (FⅧRAg) were assayed by immunohistochemistry. Microvascular density was assessed by FⅧRAg immunoreactivity. The intensity of immunoreactivity was graded according to the percentage of positive tumor cells. Results: No eNOS and VEGF were expressed in the astrocytes and vascular endothelium in astrocytic hyperplasia. The expression of eNOS or VEGF was light in low-grade astrocytoma and strong in glioblastoma. eNOS expression in astrocytoma was very positively correlated with VEGF. eNOS and VEGF expression in anaplastic astrocytoma was median in contrast to the low grade astrocytoma and glioblastoma. Lower microvascular density was found in low grade astrocytoma than that in higher grade malignant ones. The expressions of eNOS and VEGF were correlated with microvascular density and tumor malignancy. Conclusion: This finding suggests that eNOS and VEGF may have cooperative effect in tumor angiogenesis and play an important role in the pathogenesis of primary astrocytoma.

Relationship between Ki-67 and CD44 expression and microvascular formation in gastric stromal tumor tissues

BACKGROUND A gastric stromal tumor(GST)is a mesenchymal tumor that occurs in the gastrointestinal tract;its biological characteristics are highly complex.Clinically,the severity of a GST is often evaluated by factors such as risk classification,tumor size,and mitotic figures.However,these indicators are not very accurate.Even patients classified as low risk are also at risk of metastasis and recurrence.Therefore,more accurate and objective clinical biological behavior evaluations are urgently needed.AIM To determine the relationship between Ki-67 and CD44 expression in GSTs and microvessel formation and prognosis.METHODS Eighty-six GST tissue specimens from our hospital were selected for this study.The immunohistochemical staining technique was used to detect Ki-67,CD44,and microvessel density(MVD)in the collected samples to analyze the different risk grades and mitotic figures.In addition,this approach was used to determine the differences in the expression of Ki-67 and CD44 in GST tissues with varying lesion diameters.RESULTS In GSTs with positive expression of the Ki-67 protein,the proportions of patients with medium-to-high risk and more than five mitotic counts were 24.07%and 38.89%,respectively.In GSTs with positive expression of the CD44 protein,the proportions of patients with medium-to-high risk and more than five mitotic counts were 23.73%and 38.98%,respectively.In GSTs with negative expression of the Ki-67 protein,these values were relatively high(3.70%and 11.11%,respectively).The MVD in GSTs with positive and negative expression of the CD44 protein was 15.92±2.94 and 13.86±2.98/Hp,respectively;the difference between the two groups was significant(P<0.05).CONCLUSION Ki-67 and CD44 expression in GSTs is correlated with the grade of tumor risk and mitotic figures.CD44 expression is correlated with microvessel formation in tumor tissues.

Relationship between the Expression of E-cadherin and Microvessel Density in Lung Cancer and Its Significance

To study the relationship between the expression of E-cadherin andmicrovessel density (MVD) in lung cancer. Methods: The expression of E-cadherin and factor VIII wasdetected in 104 lung cancer tissues by an immunohistochemical method, and MVD was calculated by animage-analysis system. Results: The expression of E-cadherin was significantly related to thedifferentiation of lung cancers (P 【 0.05). A negative correlation was found between E-cadherinexpression and MVD in lung cancer tissues (P=0.047). Conclusion: Down-expression of E-cadherin andan increase of MVD may play an important role in the invasion and metastasis of lung cancer, and mayalso be used as a useful marker for tumor prognosis.

Pathology of diabetic myocardiac microangiopathy

Objective To investigate the cause of high cardiovascular lethality in patients with diabetics mellitus. Methods Sections from autopsied coronary arteries and myocardium of dead patients with non-insulin-dependent diabetics mellitus and 12 dead control subjects were used for histomorphometric studies. Results The coronary atherosclerotic lesion in diabetics patients was not different in severity fi＇om those in controls. Nor was there difference in number ofmyofibers or diameters of myoeardic fibers and capillaries.But the capillary density and the ratio of capillary number to myocardic fiber number in diabetics group were significeantly reduced compared with control group（P〈0.0 l）,and the capillary basement membrane in the former was significantly thicker than in the latter（P〈0.01）.Conclision The decrease in number of capillaries and the thickening of basement membrane enhance myocardiac vulnerability to further ischemia and hypoxia,which may undelie high lethality of myocardiopathy in diabetic patients.

Effects of delayed estrogen treatment and 20-HETE synthesis inhibition on postischemic pial artery response to acetylcholine in rats

Relatively little is known about the effects of estrogen on postischemic cerebral vasomotor dynamics after ischemic injury. Emerging hypotheses suggest that the timing after menopause at which hormone replacement is initiated might be important and might modulate the potential benefits of estrogen on brain rescue once a cerebral ischemic event occurs. Therefore, we sought to determine if protracted hypoestrogenicity modifies estrogen’s protective effects on postischemic pial artery dilatory dysfunction and if the arachidonic acid metabolite 20-hydroxyeicosatetraeonic (20-HETE) contributes to the dysfunction. Pial artery dilation to acetylcholine was examined before and 1 hour after 15 minutes forebrain ischemia. The rat study groups included: sexually mature males (M), naive (N), OVX (OV), estrogen-treated OVX females (E1;estrogen started 1 week post ovariectomy) and delayed estrogen-treated (E10;started 10 weeks post ovariectomy) females. Postischemic responses were assessed before and after superfusion of the 20-HETE synthesis inhibitor N-hydroxy-N’-(4-butyl-2-methylphenyl)-formamidine (HET0016). Postischemic acetylcholine dilation was depressed in M, OV and E10 compared to N and E1 rats. Compared to E1, delayed estrogen replacement worsened acetylcholine-induced dilation. Postischemic microvascular estrogen receptor alpha (ERα) density was similar in the OV, E1 and E10 rats. Postischemic application of HET0016 failed to improve acetylcholine dilation. Continuous infusion of HET0016 during and after ischemia did not reverse postischemic pial vasodilatory dysfunction. Timing of estrogen replacement may be critical for vascular health after cerebral ischemic injury. Postischemic loss of acetylcholine reactivity does not appear to involve mechanisms related to 20-HETE synthesis or microvascular ERα expression.

COX-2 expression in gastric cancer and its relationship with angiogenesis using tissue microarray

AIM: To explore the expression and clinicopathological significance of cyclooxygenase-2 (COX-2) and microvessel density (MVD) in gastric carcinogenesis, and to investigate their roles in the invasion and the relationship between biological behaviors and prognosis of gastric cancer. METHODS: Using Envision immunohistochemistry, COX-2 and CD34 expressions in gastric cancer tissue array were examined. MVD was counted and the relationship between the biological behaviors and prognosis was analyzed. RESULTS: The expression of COX-2 in gastric cancer tissue was significantly higher than that in normal mucosa (χ2 = 12.191, P < 0.05). The over-expression of COX-2 in gastric cancer was obviously related to metastasis and depth of invasion (χ2 = 6.315, P < 0.05), but not related to the histological type and Borrmann type (χ2 = 5.391 and χ2 = 2.228, respectively). Moreover, MVD in gastric cancer tissues was significantly higher than that in the normal mucosa (65.49 ± 20.64 vs 36.21 ± 18.47, t/F = 7.53, P < 0. 05). MVD was related to the histologic type and metastasis (t/F = 3.68 and t/F = 4.214, respectively, P < 0. 05), but not related to the depth of invasion and Borrmann type (t/F = 0.583 and t/F = 0.459, respectively). MVD in COX-2-positive tissues was markedly higher compared to COX-2-negative tissues, indicating a positive correlation between COX-2 expression and MVD (t = 13.12, P < 0. 05). CONCLUSION: Tissue microarray (TMA) is a powerful tool for rapid identifi cation of the molecular alterations in gastric cancer. COX-2 expression, via inducingangiogenesis, may play an important role in gastric carcinogenesis. It could be served as a determinant factor for clinical prognosis and curative effect.

Anti-Helicobacter pylori therapy followed by celecoxib on progression of gastric precancerous lesions

AIM： To evaluate whether celecoxib, a selective cyclooxygenase 2 （COX-2） inhibitor, could reduce the severity of gastric precancerous lesions following Hel/cobacter pylori （H pylorl） eradication. METHODS： H pylori-eradicated patients with gastric precancerous lesions randomly received either celecoxib （n = 30） or placebo （n = 30） for up to 3 mo. COX-2 expression and activity was determined by immunostaining and prostaglandin E2 （PGE2） assay, cell proliferation by Ki-67 immunostaining, apoptosis by TUNEL staining and angiogenesis by microvascular density （MVD） assay using CD31 staining.RESULTS： COX-2 protein expression was significantly increased in gastric precancerous lesions （atrophy, intestinal metaplasia and dysplasia, respectively） compared with chronic gastritis, and was concomitant with an increase in cell proliferation and angiogenesis. A significant improvement in precancerous lesions was observed in patients who received celecoxib compared with those who received placebo （P 〈 0.001）. Of these three changes, 84.6% of sites with dysplasia regressed in patients treated with celecoxib （P = 0.002） compared with 60% in the placebo group, suggesting that celecoxib was effective on the regression of dysplasia. COX-2 protein expression （P 〈 0.001） and COX-2 activity （P 〈 0.001） in the gastric tissues were consistently lower in celecoxib-treated patients compared with the placebo-treated subjects. Moreover, it was also shown that celecoxib suppressed cell proliferation （P 〈 0.01）, induced cell apoptosis （P 〈 0.01） and inhibited angiogenesis with decreased MVD （P 〈 0.001）. However, all of these effects were not seen in placebo-treated subjects. Furthermore, COX-2 inhibition resulted in the up-regulation of PPARy expression, a protective molecule with anti-neoplastic effects. CONCLUSION： H pylori eradication therapy followed by celecoxib treatment improves gastric precancerous lesions by inhibiting COX-2 activity, inducing apoptosis, and suppressing cell proliferation and angiogenesis.

Microvessel density is a prognostic marker of human gastric cancer

AIM: To investigate whether microvessel density (MVD) is related with prognosis in gastric cancer patients, and the expression of cyclooxygenase-2 (COX-2) and vessel endothelial growth factor (VEGF) so as to determine the possible role of COX-2 and VEGF in gastric cancer angiogenesis.METHODS: Forty-seven formalin-fixed paraffin-embedded tissue samples of gastric cancer were evaluated for COX-2, VEGF by immunohitochemical staining. To assess tumor angiogenesis, MVD was determined by immunohitochemical staining of endothelial protein factor Ⅷ-related antigen. The relationship among COX-2 and VEGF expression, MVD, and clinicopathologic parameters was analyzed. RESULTS: Among the 67 samples, high MVD was significantly associated with lymph node metastasis and poor survival. Multivariate survival analysis showed that MVD value and lymph node metastasis were independent prognostic factors. The expression rate of COX-2 and VEGF was significantly higher than that of the adjacent tissues. COX-2 and VEGF expression in gastric cancer was significantly correlated with tumor differentiation and depth of invasion, but not with survival. The mean MVD value of COX-2 or VEGF positive tumors was higher than that of COX-2 or VEGF negative tumors. A significant correlation was found between the expressions of COX-2and VEGF. CONCLUSION: MVD may be one of the important prognostic factors for gastric cancer patients. COX-2 and VEGF may play an important role in tumor progression by stimulating angiogenesis. VEGF might play a main role in the COX-2 angiogenic pathway. The inhibition of angiogenesis or COX-2, VEGF activity may have an important therapeutic benefit in the control of gastric cancer.