Percutaneous microwave ablation of uterine fibroids: correlation between shrinkage and trend symptoms.

PURPOSE: To assess a correlation between the shrinkage of the fibroid and the course of the symptoms. MATERIAL AND METHODS: Fourteen patients with symptomatic uterine leiomyomas (mean fibroid volume: 111.45 cm3) underwent percutaneous microwave ablation. Contrast-enhanced MRI follow-up was performed before and after treatment to evaluate the volume shrinkage. Two scores obtained from the Uterine Fibroids Symptom and Quality of Life questionnaire were used to perform a clinical follow-up to evaluate the symptoms and the quality of life at baseline, and at 3, 6 and 12 months after treatment. RESULTS: All patients were treated, no complications occurred. During a mean MR follow-up of 8.1 months we observed shrinkage of the fibroids in all patients (mean 70.3 cm3). During 12 months clinical follow-up, we observed a significant improvement of symptoms and an excellent improvement of quality of life (p < .001). CONCLUSION: Uterine fibroids percutaneous microwave ablation is a safe tool to obtain a significant improvement in quality of life for all the patients of our cohort.

Quantification of heterogeneity to classify benign parotid tumors: a feasibility study on most frequent histotypes.

Aim: To differentiate Warthin tumors (WTs) and pleomorphic adenomas (PAs) measuring heterogeneity of intravoxel incoherent motion (IVIM) and dynamic-contrast enhanced-magnetic resonance imaging biomarkers. Methods: Volumes of interest were traced on 18 WT and 18 PA in 25 patients. For each IVIM and dynamic-contrast enhanced biomarker, histogram parameters were calculated and then compared using the Wilcoxon-signed-rank test. Receiver operating characteristic curves and multivariate analysis were employed to identify the parameters and their pairs with the best accuracy. Results: Most of the biomarkers exhibited significant difference (p < 0.05) between PA and WT for histogram parameters. Time to peak median and skewness, and D* median and entropy showed the highest area under the curve. No meaningful improvement of accuracy was obtained using two features. Conclusion: IVIM and dynamic-contrast enhanced histogram descriptors may help in the classification of WT and PA.

Percutaneous microwave ablation of renal angiomyolipomas in tuberous sclerosis complex to improve the quality of life: preliminary experience in an Italian center.

AIM: To evaluate efficacy, safety and quality of life of the patients with renal angiomyolipomas (AMLs) associated with tuberous sclerosis complex (TSC) treated with percutaneous microwave ablation (MWA). MATERIALS AND METHODS: Nine patients (7 females and 2 males; mean age 27.6 years, range 23-34), with 10 renal AMLs with a mean size of 6.3 cm (range 4.5-8.5) were treated with image-guided percutaneous MWA. Indications for treatment were the risk of rupture/hemorrhage due to size greater than 4 cm and symptomatology; in one case, a previous hemorrhage was the indication for treatment. During follow-up, the volume of the ablated AMLs and its relationship with the relief of symptoms were registered. Technical and clinical success, safety, and quality of life (QOL) were evaluated in a mean follow-up of 9 months (range 3-12). RESULTS: Technical success was obtained in all cases. Clinical success was obtained in all cases; the volume of the ablated AMLs was not related with symptoms relief; all patients referred a significant improvement in their QOL, with a regularization of daily activities. There were no major procedural complications or delayed adverse events. A small self-limited post-procedural subcapsular hematoma was registered. Post-ablation syndrome was registered in 5 cases and was self-limited in all cases. CONCLUSIONS: Symptoms relief, lower risk of hemorrhage and a normalized QOL were obtained in all patients with a safe and mini-invasive procedure.

In-stent restenosis associated with dual-layer Roadsaver carotid artery stent: a retrospective single-center study.

AIM: To evaluate the incidence of in-stent restenosis (ISR) at 12-month follow-up, in patients treated with new dual-layer Roadsaver (Terumo Corp, Tokyo, Japan) carotid artery stent (CAS). MATERIALS AND METHODS: Thirteen patients underwent CAS and received a Roadsaver. Neurological examination was performed in all patients. Carotid stenosis was revealed by Doppler ultrasound (DUS) and multidetector CT (MDCT) scan. Four patients presented a peak systolic velocity (PSV) between 130 and 150 cm/s, six a PSV between 150 and 180 cm/s, and three a PSV > 180 cm/s. MDCT gave further anatomic information. Direct stenting was performed in 11 (84.6%) cases, whereas in 2 (15.4%) cases predilatation was required. In all cases postdilatation was performed. Technical and clinical success and safety were evaluated. Stent patency was evaluated during the 12-month follow-up. RESULTS: Technical success was achieved in all cases. In three patients a nonsignificant residual stenosis < 30% has been reported. No major complications during or after the procedure occurred. One patient (7.7%) showed a transitory bradycardia during angioplasty. One (7.7%) local bleeding at the puncture site treated conservatively occurred. All the neurological examinations performed 24 h and 30 days after the procedure were negative. No significant ISR was registered. In 2 patients, < 30% ISR was revealed at DUS performed after 6 months and confirmed at 12 months. In both patients CEUS and MDCT denied the presence of significant stenosis. CONCLUSIONS: Roadsaver stent seems to be durable. Further studies with longer-term outcome are necessary to confirm our results.

Treatment of venous stenosis in oncologic patients.

Symptomatic obstruction related to malignant involvement of large veins may occur in central veins both in the thoracic and pelvic regions, and in the abdominal region of the body. Both cases represent a therapeutic challenge, and endovascular revascularization, consisting of angioplasty and stent placement, is safe and effective. Superior vena cava stenting has become widespread in the management of occlusive venous disease. The percutaneous placement of large expandable metal stents allows rapid restoration of normal blood flow in the majority of patients, thus improving symptoms. Published data on the diagnosis and treatment of symptomatic cancer-related iliocaval obstructions are limited and mainly consist of case reports and small case series. The present review reports the current state of endovascular treatment for both superior vena cava occlusion and iliac compression syndrome in cancer patients.

Hypoxia and tumor angiogenesis in the era of hepatocellular carcinoma transarterial loco-regional treatments.

This review focuses upon interactions and potential therapeutic targets in the 'vicious cycle' between hypoxia and neoangiogenesis following treatment of hepatocellular carcinoma with transarterial loco-regional therapies. Biomarkers correlated with angiogenesis have been studied by many authors as prognostic determinants following transarterial intrahepatic therapy. According to these results future therapies directed toward specific factors related to angiogenesis could play a significant role in preventing local tumor recurrence and remote metastasis.

A multiparametric analysis combining DCE-MRI- and IVIM -derived parameters to improve differentiation of parotid tumors: a pilot study.

AIM: To evaluate dynamic contrast-enhanced (DCE)-MRI and diffusion weighted (DW)-MRI diagnostic value to differentiate Warthin tumors (WT) by pleomorphic adenomas (PA). MATERIALS & METHODS: Seven WT and seven PA were examined. DCE- and  DW-MRI parameters were extracted from volumes of interest; volume of interest-based averages and standard deviations were calculated. Statistical analysis included: linear discriminant analysis, receiver operating characteristic curves, sensitivity and specificity. RESULTS: No single feature was able to differentiate WT by PA (p > 0.05); linear discriminant analysis analysis showed that a combination of all features or combinations of feature pairs (namely: Ktrans(std) & f(std), Ktrans(std) & D(std), kep(std) & D(std), MRE(av) & TTP(av)) might achieve sensitivity (SENS), specificity (SPEC) = 100%, with a slight reduction after cross-validation analysis (SENS = 0.875; SPEC = 1). CONCLUSION: Although preliminary and not conclusive, our results suggest that differentiation between WT and PA is possible through a multiparametric approach based on combination of DCE- and DW-MRI parameters.

Magnetic Resonance Imaging Evaluation in Neoadjuvant Therapy of Locally Advanced Rectal Cancer: A Systematic Review.

BACKGROUND: The aim of the study was to present an update concerning several imaging modalities in diagnosis, staging and pre-surgery treatment response assessment in locally advanced rectal cancer (LARC). Modalities include: traditional morphological magnetic resonance imaging (MRI), functional MRI such as dynamic contrast enhanced MRI (DCE-MRI) and diffusion weighted imaging (DWI). A systematic review about the diagnostic accuracy in neoadjuvant therapy response assessment of MRI, DCE-MRI, DWI and Positron Emission Tomography/Computed Tomography (PET/CT) has been also reported. METHODS: Several electronic databases were searched including PubMed, Scopus, Web of Science, and Google Scholar. All the studies included in this review reported findings about therapy response assessment in LARC by means of MRI, DCE-MRI, DWI and PET/CT with details about diagnostic accuracy, true and false negatives, true and false positives. Forest plot and receiver operating characteristic (ROC) curves analysis were performed. Risk of bias and the applicability at study level were calculated. RESULTS: Twenty-five papers were identified. ROC curves analysis demonstrated that multimodal imaging integrating morphological and functional MRI features had the best accuracy both in term of sensitivity and specificity to evaluate preoperative therapy response in LARC. DCE-MRI following to PET/CT showed high diagnostic accuracy and their results are also more reliable than conventional MRI and DWI alone. CONCLUSIONS: Morphological MRI is the modality of choice for rectal cancer staging permitting a correct assessment of the disease extent, of the lymph node involvement, of the mesorectal fascia and of the sphincter complex for surgical planning. Multimodal imaging and functional DCE-MRI may also help in the assessment of treatment response allowing to guide the surgeon versus conservative strategies and/or tailored approach such as "wait and see" policy.

Cone beam computed tomography images fusion in predicting lung ablation volumes: a feasibility study.

BACKGROUND: Recently different software with the ability to plan ablation volumes have been developed in order to minimize the number of attempts of positioning electrodes and to improve a safe overall tumor coverage. PURPOSE: To assess the feasibility of three-dimensional cone beam computed tomography (3D CBCT) fusion imaging with "virtual probe" positioning, to predict ablation volume in lung tumors treated percutaneously. MATERIAL AND METHODS: Pre-procedural computed tomography contrast-enhanced scans (CECT) were merged with a CBCT volume obtained to plan the ablation. An offline tumor segmentation was performed to determine the number of antennae and their positioning within the tumor. The volume of ablation obtained, evaluated on CECT performed after 1 month, was compared with the pre-procedural predicted one. Feasibility was assessed on the basis of accuracy evaluation (visual evaluation [VE] and quantitative evaluation [QE]), technical success (TS), and technical effectiveness (TE). RESULTS: Seven of the patients with lung tumor treated by percutaneous thermal ablation were selected and treated on the basis of the 3D CBCT fusion imaging. In all cases the volume of ablation predicted was in accordance with that obtained. The difference in volume between predicted ablation volumes and obtained ones on CECT at 1 month was 1.8 cm(3) (SD ± 2, min. 0.4, max. 0.9) for MW and 0.9 cm(3) (SD ± 1.1, min. 0.1, max. 0.7) for RF. CONCLUSION: Use of pre-procedural 3D CBCT fusion imaging could be useful to define expected ablation volumes. However, more patients are needed to ensure stronger evidence.

The role of endovascular treatment of pelvic fracture bleeding in emergency settings.

PURPOSE: To evaluate the role of endovascular treatment for controlling haemorrhage in haemodynamically unstable patients with pelvic bone fractures and to relate clinical efficacy to pre-procedural variables. MATERIALS AND METHODS: From March 2009 through April 2013, 168 patients with major pelvic trauma associated with high-flow haemorrhage were referred to our emergency department and were retrospectively reviewed. Pelvic arteries involved were one or more per patient. Embolisation was performed using various materials (micro-coils, Spongostan, plug, glue, covered stent), and technical success, complications, treatment success, clinical efficacy, rebleeding, and mortality rates were assessed. Factors influencing clinical efficacy were also evaluated. RESULTS: The technical success rate was 100%; no complications occurred during the procedures. Treatment was successful in 94.6% cases, and clinical efficacy was 85.7%. Three patients had to undergo a second arteriography due to recurrent haemorrhage. Fifteen patients died. Pre-embolisation transfusion demand was significantly associated with clinical efficacy. CONCLUSIONS: Percutaneous embolisation of pelvic bleeding may be considered a safe, effective, and minimally invasive therapeutic option. As haemodynamic stability is the first objective with traumatic haemorrhagic patient, arterial embolisation can assume a primary role. On the basis of our results, pre-procedural transfusion status may be considered a prognostic factor. KEY POINTS: • The series presented is one of the largest in a single centre. • Arterial embolisation is a life-saving procedure in patients with pelvic haemorrhage. • In pelvic traumas associated with haemorrhage, prognosis is dependent upon prompt treatment. • Transfusion status is significantly related to clinical efficacy.

Standardized Index of Shape (SIS): a quantitative DCE-MRI parameter to discriminate responders by non-responders after neoadjuvant therapy in LARC.

OBJECTIVES: To investigate the potential of DCE-MRI to discriminate responders from non-responders after neoadjuvant chemo-radiotherapy (CRT) for locally advanced rectal cancer (LARC). We investigated several shape parameters for the time-intensity curve (TIC) in order to identify the best combination of parameters between two linear parameter classifiers. METHODS: Seventy-four consecutive patients with LARC were enrolled in a prospective study approved by our ethics committee. Each patient gave written informed consent. After surgery, pathological TNM and tumour regression grade (TRG) were estimated. DCE-MRI semi-quantitative analysis (sqMRI) was performed to identify the best parameter or parameter combination to discriminate responders from non-responders in response monitoring to CRT. Percentage changes of TIC shape descriptors from the baseline to the presurgical scan were assessed and correlated with TRG. Receiver operating characteristic analysis and linear classifier were applied. RESULTS: Forty-six patients (62.2%) were classified as responders, while 28 subjects (37.8%) were considered as non-responders. sqMRI reached a sensitivity of 93.5% and a specificity of 82.1% combining the percentage change in Maximum Signal Difference (ΔMSD) and Wash-out Slope (ΔWOS), the Standardized Index of Shape (SIS). CONCLUSIONS: SIS obtains the best result in discriminating responders from non-responders after CRT in LARC, with a cut-off value of -3.0%. KEY POINTS: • DCE-MRI shape descriptors are investigated to assess preoperative CRT response in LARC. • Identification of the best TIC shape descriptors combination through a linear classifier. • Identification of a single MRI index to predict neoadjuvant treatment response.

Role of percutaneous transcatheter embolization (PTE) in the treatment of spontaneous bleeding associated with anticoagulant therapy.

PURPOSE: To evaluate safety and clinical efficacy of percutaneous transcatheter embolization (PTE) in the treatment of spontaneous bleedings (SBs) in patients submitted to chronic anticoagulation therapy. MATERIALS AND METHODS: From January 2007 to December 2012, 20 patients (mean age 75.8 years, range 68-91 years) with 23 SBs were retrospectively evaluated. Active bleeding was documented by contrast enhanced-multidetector row computed tomography (CE-MDCT). PTE was performed using different embolic agents. Technical success (TS), clinical success (CS), late success (LS) and mortality rate (M) related to the angiographic procedure and complications were evaluated. RESULTS: CE-MDCT and digital subtraction angiography (DSA) identified active bleeding sites in 18 cases (18/20). In two cases (2/20) DSA did not confirm the arterial bleeding diagnosed on CE-MDCT. Twenty-three sessions of PTE were performed. TS, CS, LS and M were, respectively, 100, 85, 15 and 0%. No major complications were observed. CONCLUSIONS: PTE could be considered a safe and effective "first line" approach to treat SB associated with anticoagulation therapy.

Ultra-low profile polymer-filled stent graft for abdominal aortic aneurysm treatment: a two-year follow-up.

PURPOSE: This study evaluated 2 years of follow-up of the Ovation Abdominal Stent Graft System (TriVascular Inc., Santa Rosa, CA, USA) for endovascular repair (EVAR) of abdominal aortic aneurysms (AAAs). MATERIALS AND METHODS: This retrospective multicentre study included 36 patients (median age, 73.6 year) with AAAs (mean diameter, 5.65 cm) treated with the Ovation stent graft and followed up for at least 2 years. Safety and effectiveness of the Ovation stent graft were evaluated. Indications for EVAR were the following: AAA ≥5 cm, neck length ≥7 mm, angulation ≤60° and diameter <30 mm; the presence of neck calcification and thrombosis was not considered a contraindication; distal iliac landing zone length of 10 mm, and diameter between 5 and 20 mm. Patients were treated under a common protocol, including clinical and imaging follow-up at discharge, 30 days, 6 months, and annually for 5 years. Adverse events, clinical and imaging data and possible re-intervention were recorded. RESULTS: The Ovation stent graft was implanted successfully in 36 patients (100 %). None of the patients required conversion to open surgery, and none presented with an aneurysm rupture. Endograft stent fracture or migration was not observed in any case. No type I, III or IV endoleaks were observed; in 12 patients (33.3 %), a type II endoleak was noted, in one case with sac enlargement but not treated due to concomitant comorbidities and the patient's decision. CONCLUSIONS: The 2-year results of the Ovation Abdominal Stent Graft System demonstrate excellent safety and effectiveness in the treatment of patients with AAAs, particularly in those with challenging anatomical characteristics.

Multiparametric MRI for prostate cancer detection: performance in patients with prostate-specific antigen values between 2.5 and 10 ng/mL.

PURPOSE: To assess the diagnostic performance of multiparametric MRI (mpMRI), in the detection of prostate cancer, including morphologic sequences (mMRI), diffusion-weighted imaging (DWI), and MR spectroscopy (MRS). Combined morphological and functional MRI scoring systems was used for urological­radiological work-up of patients with a prostate-specific antigen (PSA) value ≤ 10 ng/mL. MATERIALS AND METHODS: The study included 136 of 200 consecutive patients with PSA values between 2.5 and 4 ng/mL and an abnormal digital rectal examination (DRE), or patients with PSA values between 4 and 10 ng/mL, independently from DRE. Each patient provided informed consent to undergo at serum free/total PSA ratio (f/t PSA) assay, mMRI, MRS, DWI, and transrectal ultrasonography (TRUS) biopsy. The MRI datasets were scored singularly; then mMRI and DWI, mMRI and MRS data were combined in a coupled score, and finally mMRI, DWI, and MRS data were combined in a single score (cMRI score). RESULTS: Scores were correlated to negative biopsies and significant/insignificant Gleason score biopsies. Receiver-operator-characteristic curve and McNemar tests were performed. Cancer was diagnosed in 18% of patients. The cMRI score showed: (i) the highest sensitivity (0.84) and negative predictive value (0.93); (ii) a significant correlation with Gleason score; and (iii) a statistically different median value between significant and insignificant Gleason score. CONCLUSION: The cMRI score could identify patients with a PSA≤10 ng/mL who will have a negative work-up, for its high negative predictive value, and patients at high risk for significant prostate cancer because of its correlation with the Gleason score

Transcatheter embolisation of iatrogenic renal vascular injuries.

PURPOSE: The aim of our study was to review our experience and long-term follow-up in the treatment of iatrogenic renal vascular injuries using transcatheter embolisation. MATERIALS AND METHODS: Our retrospective analysis of cases collected in two interventional centres consists of a total of 21 patients who underwent renal arterial embolisation (RAE) for iatrogenic arterial kidney bleeding. Biopsy (n = 4), percutaneous nephrolithotomy (n = 4), nephron-sparing surgery (n = 4), guidewire-induced arterial perforation during coronary angiography or renal stenting (n = 3), percutaneous nephrostomy (n = 3), renal endopyelotomy/pyeloplasty (n = 2) and surgical nephrectomy were the iatrogenic causes. Seven patients presented with haemodynamic instability requiring blood transfusion (33.3%), the remaining were haemodynamically stable (66.7%). Diagnostic renal angiography revealed 9 actively bleeding vessels, 6 pseudoaneurysms, 4 arteriovenous fistulas and 1 arterio-calyceal fistula. In one patient selective renal arteriography was negative probably because the bleeding observed at CT angiography was self-limited. Twenty-one embolisation procedures were performed in 20 patients; one patient required a second embolisation 3 h after the first one. Embolisation was performed with microcoils, polyvinyl alcohol particles, embospheres, spongostan emulsion and vascular plug. RESULTS: The technical success rate was 100%. The overall clinical success rate was 95%. Apart from a patient who died due to disseminated intravascular coagulation, no major complications requiring intensive care treatment were encountered during or after the procedures. No patient required emergency surgery or subsequent surgical treatment. No statistically significant differences in eGFR or renal function stage appeared after RAE. CONCLUSIONS: Percutaneous treatment can be proposed as a first-line treatment in iatrogenic renal arterial injuries, resulting in a safe and effective procedure.

Systematic review of minimally invasive ablation treatment for locally advanced pancreatic cancer.

Unresectable locally advanced pancreatic cancer with or without metastatic disease is associated with a very poor prognosis. Ablation techniques are based on direct application of chemical, thermal, or electrical energy to a tumor, which leads to cellular necrosis. Initial studies about ablation therapies of the pancreas were associated with significant morbidity and mortality, which limited widespread adoption. Modifications to the various applications, in particular combining the techniques with high-quality imaging and intra-operative approach has enabled real-time treatment monitoring and significant improvements in safety. Inoperable cases of pancreatic cancer have been treated by various ablation techniques in the last few years with promising results. The purpose of this review is to present the current status of local ablative therapies in the treatment of pancreatic advanced tumor.

Usefulness and safety of biliary percutaneous transluminal forceps biopsy (PTFB): our experience.

AIM: To evaluate the usefulness and safety of percutaneous transluminal forceps biopsy in patients suspected of having a malignant biliary obstruction. MATERIAL AND METHODS: Forty consecutive patients (21 men and 19 women; mean age, 71.9 years) underwent forceps biopsy through percutaneous transhepatic biliary access performed to drain bile. Lesions involved the common bile duct (n 8), common hepatic duct (n 18), hilum (n 6), ampullary segment of the common bile duct (n 8) and were biopsied with 7-F biopsy forceps. Final diagnosis was confirmed with pathologic findings at surgery, or clinical and radiologic follow-up. RESULTS: Twenty-one of 40 biopsies resulted in correct diagnosis of malignancy. Thirteen biopsy diagnosis were proved to be true-negative. There were six false-negative and no false-positive diagnoses. Sensitivity, specificity and accuracy in aspecific biliary obstructions were 85%, 100% and 88,7% respectively. Sensitivity of biopsy in malignancies was higher than in benign obstructions (100% vs 68,4%, CI = 95%). Sensitivity was lower in the hilum tract and in the common bile duct than in other sites (CI = 95%). No major complications related to biopsy procedures occurred. CONCLUSIONS: Percutaneous transluminal forceps biopsy is a safe procedure, easy to perform through a transhepatic biliary drainage tract, providing high accuracy in the diagnosis of malignant biliary obstructions.

Microwave ablation of pancreatic head cancer: safety and efficacy.

PURPOSE: To evaluate the safety and efficacy of percutaneous microwave (MW) ablation treatment in locally advanced, nonresectable, nonmetastatic pancreatic head cancer. MATERIALS AND METHODS: Ten patients with pancreatic head cancer treated with percutaneous (n = 5) or laparotomic (n = 5) MW ablation were retrospectively reviewed. The MW generator used (45 W at 915 MHz) was connected by coaxial cable to 14-gauge straight MW antennas with a 3.7- or 2-cm radiating section. One or two antennae were used, with an ablation time of 10 minutes. Ultrasonographic (US) and combined US/cone-beam computed tomographic (CT) guidance were used in five patients each. Follow-up was performed by CT after 1, 3, 6, and, when possible, 12 months. Tumor response was assessed per Response Evaluation Criteria In Solid Tumors (version 1.1) and Choi criteria. The feasibility, safety, and major and minor complications associated with quality of life (QOL) were recorded prospectively. RESULTS: The procedure was feasible in all patients (100%). One late major complication was observed in one patient, and no visceral injury was detected. No patient had further surgery, and all minor complications resolved during the hospital stay. An improvement in QOL was observed in all patients despite a tendency to return to preoperative levels in the months following the procedure, without the influence of minor complications. No repeat treatment was performed. CONCLUSIONS: Despite the small number of patients, the present results can be considered encouraging, showing that MW ablation is a feasible approach in the palliative treatment of pancreatic tumors.

CXCR4/YY1 inhibition impairs VEGF network and angiogenesis during malignancy.

Tumor growth requires neoangiogenesis. VEGF is the most potent proangiogenic factor. Dysregulation of hypoxia-inducible factor (HIF) or cytokine stimuli such as those involving the chemokine receptor 4/stromal-derived cell factor 1 (CXCR4/SDF-1) axis are the major cause of ectopic overexpression of VEGF in tumors. Although the CXCR4/SDF-1 pathway is well characterized, the transcription factors executing the effector function of this signaling are poorly understood. The multifunctional Yin Yang 1 (YY1) protein is highly expressed in different types of cancers and may regulate some cancer-related genes. The network involving CXCR4/YY1 and neoangiogenesis could play a major role in cancer progression. In this study we have shown that YY1 forms an active complex with HIF-1alpha at VEGF gene promoters and increases VEGF transcription and expression observed by RT-PCR, ELISA, and Western blot using two different antibodies against VEGFB. Long-term treatment with T22 peptide (a CXCR4/SDF-1 inhibitor) and YY1 silencing can reduce in vivo systemic neoangiogenesis (P < 0.01 and P < 0.05 vs. control, respectively) during metastasis. Moreover, using an in vitro angiogenesis assay, we observed that YY1 silencing led to a 60% reduction in branches (P < 0.01) and tube length (P < 0.02) and a 75% reduction in tube area (P < 0.001) compared with control cells. A similar reduction was observed using T22 peptide. We demonstrated that T22 peptide determines YY1 cytoplasmic accumulation by reducing its phosphorylation via down-regulation of AKT, identifying a crosstalk mechanism involving CXCR4/YY1. Thus, YY1 may represent a crucial molecular target for antiangiogenic therapy during cancer progression.

Role of endothelial nitric oxide synthase (eNOS) in chronic stress-promoted tumour growth.

Accumulating evidence suggests that chronic stress can be a cofactor for the initiation and progression of cancer. Here we evaluated the role of endothelial nitric oxide synthase (eNOS) in stress-promoted tumour growth of murine B16F10 melanoma cell line in C57BL/6 mice. Animals subjected to restraint stress showed increased levels adrenocorticotropic hormone, enlarged adrenal glands, reduced thymus weight and a 3.61-fold increase in tumour growth in respect to no-stressed animals. Tumour growth was significantly reduced in mice treated with the ß-antagonist propranolol. Tumour samples obtained from stressed mice displayed high levels of vascular endothelial growth factor (VEGF) protein in immunohistochemistry. Because VEGF can induce eNOS increase, and nitric oxide is a relevant factor in angiogenesis, we assessed the levels of eNOS protein by Western blot analysis. We found a significant increase in eNOS levels in tumour samples from stressed mice, indicating an involvement of this enzyme in stress-induced tumour growth. Accordingly, chronic stress did not promote tumour growth in eNOS(-/-) mice. These results disclose for the first time a pivotal role for eNOS in chronic stress-induced initiation and promotion of tumour growth.