Depletion of Ras Suppressor-1 (RSU-1) promotes cell invasion of breast cancer cells through a compensatory upregulation of a truncated isoform.

Extracellular matrix (ECM)-adhesion proteins and actin cytoskeleton are pivotal in cancer cell invasion. Ras Suppressor-1 (RSU-1), a cell-ECM adhesion protein that interacts with PINCH-1, thus being connected to Integrin Linked Kinase (ILK), alpha-parvin (PARVA), and actin cytoskeleton, is up-regulated in metastatic breast cancer (BC) samples. Apart from the originally-identified gene (RSU-1L), an alternatively-spliced isoform (RSU-1-X1) has been reported. We used non-invasive MCF-7 cells, expressing only RSU-1L, and highly invasive MDA-MB-231-LM2 expressing both isoforms and generated stable shRNA-transduced cells lacking RSU-1L, while the truncated RSU-1-X1 isoform was depleted by siRNA-mediated silencing. RSU-1L depletion in MCF-7 cells resulted in complete abrogation of tumor spheroid invasion in three-dimensional collagen gels, whereas it promoted MDA-MB-231-LM2 invasion, through a compensatory upregulation of RSU-1-X1. When RSU-1-X1 was also eliminated, RSU-1L-depletion-induced migration and invasion were drastically reduced being accompanied by reduced urokinase plasminogen activator expression. Protein expression analysis in 23 human BC samples corroborated our findings showing RSU-1L to be upregulated and RSU-1-X1 downregulated in metastatic samples. We demonstrate for the first time, that both RSU-1 isoforms promote invasion in vitro while RSU-1L elimination induces RSU-1-X1 upregulation to compensate for the loss. Hence, we propose that both isoforms should be blocked to effectively eliminate metastasis.

Diagnostic performance of quantitative diffusion tensor imaging for the differentiation of breast lesions at 3 T MRI.

BACKGROUND: Conventional breast magnetic resonance imaging (MRI), including dynamic contrast-enhanced MR mammography, may lead to ambiguous diagnosis and unnecessary biopsies. PURPOSE: To investigate the contribution of quantitative diffusion tensor imaging (DTI) in the discrimination between benign and malignant breast lesions at 3 T MRI. MATERIAL AND METHODS: The study included a total of 86 lesions (44 benign and 42 malignant) in 58 women (34 with malignant lesions, 23 with benign lesions and 1 with both types of lesions). All patients were examined on a 3 T MRI scanner. Fractional Anisotropy (FA), Mean Diffusivity (MD), Apparent Diffusion Coefficient (ADC), as well as eigenvalues (λ1, λ2, λ3) were calculated and compared between benign and malignant lesions using two different software packages (GE Functool and ExploreDTI). RESULTS: Malignant lesions exhibited significantly lower ADC values compared to benign ones (ADCmal = 1.06 × 10-3 mm2/s, ADCben = 1.54 × 10-3 mm2/s, p-value < 0.0001). FA measurements in carcinomas indicated slightly higher values than those in benign lesions (FAmal = 0.20 ±â€¯0.07, FAben = 0.15 ±â€¯0.05, p-value = 0.0003). Eigenvalues λ1, λ2, λ3, showed significantly lower values in malignant tumors compared to benign lesions and normal breast tissue. ROC curve analysis of ADC and DTI metrics demonstrated that ADC provides high diagnostic performance (AUC = 0.944) while, MD and λ1 showed best discriminative results (AUC = 0.906) for the differentiation of malignant and benign lesions in contrast to other DTI parameters. CONCLUSION: The addition of eigenvalue analysis improves DTI's ability to differentiate between benign and malignant breast lesions.

Ras suppressor-1 promotes apoptosis in breast cancer cells by inhibiting PINCH-1 and activating p53-upregulated-modulator of apoptosis (PUMA); verification from metastatic breast cancer human samples.

Metastasis, responsible for most deaths from breast cancer (BC), is a multistep process leading to cancer cell spread. Extracellular matrix (ECM)-related adhesion and apoptosis resistance play pivotal role in metastasis. Ras suppressor-1 (RSU-1) localizes to cell-ECM adhesions and binds to pro-survival adhesion protein PINCH-1. Little is known about the role of RSU-1 in BC. In the present study, we investigated the role of RSU-1 in BC metastasis using two BC cell lines that differ in terms of their metastatic potential and a set of 32 human BC samples from patients with or without lymph node metastasis. We show that RSU-1 is upregulated in the aggressive MDA-MB-231 cells compared to MCF-7 and that its silencing by siRNA leads to upregulation of PINCH-1, induction of proliferation and reduction of apoptosis through downregulation of the pro-apoptotic gene p53-upregulated-modulator-of-apoptosis (PUMA). Our findings in the cell lines were further validated in the human BC tissues where normal adjacent tissues were used as controls. We demonstrate for the first time, that RSU-1 expression is upregulated in metastatic BC samples and downregulated in non-metastatic while it is negatively correlated with PINCH-1 and positively correlated with PUMA expression, suggesting that a pro-apoptotic mechanism is in place in metastatic BC samples and identifying RSU-1 as a potentially interesting molecule that needs to be evaluated further as a novel BC metastasis biomarker.

The contribution of diffusion tensor imaging and magnetic resonance spectroscopy for the differentiation of breast lesions at 3T.

BACKGROUND: Conventional breast magnetic resonance imaging (MRI), including dynamic contrast-enhanced MR mammography (DCE-MRM), may lead to ambiguous diagnosis and unnecessary biopsies. PURPOSE: To investigate the contribution of proton MR spectroscopy (1H-MRS) combined with diffusion tensor imaging (DTI) metrics in the discrimination between benign and malignant breast lesions. MATERIAL AND METHODS: Fifty-one women with known breast abnormalities from conventional imaging were examined on a 3T MR scanner. DTI was performed during breast MRI, and fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were measured in the breast lesions and the contralateral normal breast. FA and ADC were compared between malignant lesions, benign lesions, and normal tissue. 1H-MRS was performed after gadolinium administration and choline peak was qualitatively evaluated. RESULTS: In our study 1H-MRS showed a sensitivity of 93.5%, specificity 80%, and accuracy 88.2%. FA was significantly higher in breast carcinomas compared to benign lesions. However, no significant difference was observed in ADC between benign and malignant lesions. The combination of Cho presence and FA achieved higher levels of accuracy and specificity in discriminating malignant from benign lesions over Cho presence or FA alone. CONCLUSION: In conclusion, applying DTI and 1H-MRS together, adds incremental diagnostic value in the characterization of breast lesions and may sufficiently improve the low specificity of conventional breast MRI.

Mitogen-inducible Gene-2 (MIG2) and migfilin expression is reduced in samples of human breast cancer.

BACKGROUND: Cell adhesion proteins that connect each cell to neighboring cells and the extracellular matrix play a fundamental role in metastasis. Mitogen-inducible gene-2 (MIG2), is a cell-matrix adhesion protein, which through migfilin, interacts with filamin-A, being linked to actin cytoskeleton. AIM: Recent studies have implicated both MIG2 and migfilin in cancer, but little is known regarding their expression in breast cancer. In this study, we investigated this topic. MATERIALS AND METHODS: mRNA and protein expression was examined in 30 breast cancer samples and compared to that of normal adjacent tissue using real time-polymerase chain reaction (PCR) and western blotting. RESULTS: Our results showed that expression of MIG2 and migfilin was significantly reduced in the majority of the breast cancer tissues compared to normal tissues regardless of metastatic status and disease stage. CONCLUSION: Both MIG2 and migfilin are down-regulated in breast cancer.

On the management of hyperglycaemia in critically ill patients undergoing surgery.

Hyperglycaemia is a major health risk and a negative determinant of surgical outcome. Despite its increasing prevalence, the limited treatments for restoration of normoglycaemia make its effective management a highly complex individualized clinical art. In this context, we review the mechanisms leading to hyperglycaemic damage as the basis for effective management of surgical complications of diabetic and non diabetic critically ill patients.

Practical approaches to effective management of intestinal radiation injury: benefit of resectional surgery.

AIM: To study the outcome of patients undergoing surgical resection of the bowel for sustained radiation-induced damage intractable to conservative management. METHODS: During a 7-year period we operated on 17 cases (5 male, 12 female) admitted to our surgical department with intestinal radiation injury (IRI). They were originally treated for a pelvic malignancy by surgical resection followed by postoperative radiotherapy. During follow-up, they developed radiation enteritis requiring surgical treatment due to failure of conservative management. RESULTS: IRI was located in the terminal ileum in 12 patients, in the rectum in 2 patients, in the descending colon in 2 patients, and in the cecum in one patient. All patients had resection of the affected region(s). There were no postoperative deaths, while 3 cases presented with postoperative complications (17.7%). All patients remained free of symptoms without evidence of recurrence of IRI for a median follow-up period of 42 mo (range, 6-96 mo). CONCLUSION: We report a favorable outcome without IRI recurrence of 17 patients treated by resection of the diseased bowel segment.

hTERT regulation by NF-κB and c-myc in irradiated HER2-positive breast cancer cells.

PURPOSE: Telomerase activity (TA), frequently observed in cancer, compensates for telomere shortening thus preventing cell senescence and conferring resistance to therapy. In the present study, we investigated the expression of human telomerase reverse transcriptase (hTERT) and TA and their regulation, as well as apoptotic rates and correlation with the presence of human epidermal growth factor receptor 2 (HER2), in irradiated tumour-derived breast cancer cells. MATERIALS AND METHODS: In 50 breast cancer tissue samples hTERT mRNA expression and TA were correlated with cell features (HER2, Estrogen and Progesterone Receptor status). Cells from six samples were then irradiated with 10 and 20 Gy; apoptotic rates were measured by flow cytometry, hTERT mRNA expression by real-time polymerase chain reaction and TA by telomeric repeat amplification protocol assay, at 24-144 h post-irradiation. Chromatin immunoprecipitation was performed to investigate hTERT and cellular-myelocytomatosis (c-myc) promoters' activity. HER2 gene knockdown was performed using small interfering RNA technology. RESULTS: hTERT/TA were found increased only in irradiated HER2-positive cells, which were found to be more radioresistant, while HER2 knockdown led to hTERT/TA downregulation. HER2 was found to mediate hTERT expression through activation of Nuclear Factor-kappa B (NF-κB) and c-myc. CONCLUSIONS: The present study suggests that following irradiation, HER2 receptor activates hTERT/telomerase, increasing the breast cancer cells' survival potential, through sequential induction of transcription factors NF-κΒ and c-myc.

Expression of 6 common antigenic markers in invasive ductal breast carcinoma: potential clinical implications.

Expression of estrogen (ER) and progesterone receptors, c-erbB-2 oncogene, mutant p53 antioncogene (mp53), e-cadherin adhesion, and apoptotic caspase-8 antigens in tumor relative to matched normal tissue specimens from 102 unselected patients with primary ductal breast carcinoma of various tumor grades was assessed by immunohistochemistry and correlated with patient's biologic and clinical features, such as age, menstrual status, age of menarche, tumor grade and diameter, the presence or absence of metastases, and number of infiltrated lymph nodes. We observed association of e-cadherin adhesion, ER and progesterone antigen marker expression with low histologic grade tumors and limited number of lymph node metastases and of c-erbB-2, mp53, and casp-8 antigen marker expression with high histologic grade tumors and increased number of lymph node metastases. We also observed strong correlation (P<0.05) between 4 of the 6 biomarkers and 4 of the 7 patient/tumor parameters examined. Our findings support the hypothesis of independent expression of these 4 strong biomarkers and reveal that nearly 40% of all breast tumor cases studied express similar proportions of 2 major phenotypic combinations [ER/c-erbB-2/mp53/casp-8: +/+/-/+ (19.6%) & +/-/-/+ (17.8%)]. We conclude that, in agreement with earlier reports, our findings support the diagnostic and potential prognostic value of these markers in the clinical assessment of breast cancer.

Cytogenetic damage after ischemia and reperfusion.

Tourniquets are often used to provide a bloodless operating field. However, they carry the risk of adverse effects caused by DNA damage from the free radicals generated during postischemic reperfusion of the blood. The aim of this study was to evaluate the cytogenetic damage caused by postischemic reperfusion on peripheral lymphocytes of five women and six men undergoing total knee arthroplasty "bloodless" operation using samples received before, during, immediately, and 1 h after the operations. The sister chromatid exchange assay was applied to peripheral blood lymphocyte cultures and the levels of sister chromatid exchanges were analyzed as a quantitative index of genotoxicity, along with the values of mitotic index and proliferation rate index as qualitative indices of cytotoxicity and cytostaticity, respectively. We observed that postischemic reperfusion induced cytogenetic damages specifically through reperfusion. DNA effects were most pronounced after tourniquet release and declined afterward without returning to preischemic baseline values. Our findings suggest the presence of a functional association between postischemic reperfusion and cytogenetic damage that may have important clinical implications.

Acute occlusion of the celiac axis and its branches with perforation of gastric fundus and splenic infarction, findings on spiral computed tomography: a case report.

We present the contrast-enhanced spiral CT findings in a case of acute celiac artery occlusion with gastric perforation and total splenic infarction. Spiral CT depicted thrombus in the celiac axis and its branches, stenosis of the superior mesenteric artery, splenic infarction and lack of enhancement of the gastric wall with a large necrotic gap. Spiral CT enabled prompt diagnosis and therapy in this rare condition in a patient with suspicion of acute mesenteric ischemia.

Immunophenotypic evaluation of DNA mismatch repair markers in 2 cases of synchronous histomorphologically distinct gastric adenocarcinomas with gastrointestinal stromal tumors of the proximal small bowel.

OBJECTIVES: To assess the prognostic value of combined mismatch DNA repair (MMR) phenotyping in 2 synchronous histomorphologically distinct gastric adenocarcinomas (GADCs), each accompanied by gastrointestinal stromal tumors (GISTs) of the proximal small bowel. SUMMARY BACKGROUND DATA: A 72-year-old female and a 55-year-old male patient were submitted to partial and total gastrectomy, respectively, with synchronous resection of a GIST in the proximal small bowel. The 2 patients attained contrasting survival outcomes. The female survives disease-free 20 months after surgery having received no chemotherapy. The male who received adjuvant chemotherapy developed metastases in liver and lung, and died 18 months after surgery. METHODS: We phenotype MSH2 and MLH1 protein expression in tumor relative to matched normal tissue by immunohistochemistry. RESULTS: Immunohistochemistry analysis revealed different combined MMR phenotypes for the 2 histomorhologically distinct GADCs and similar for both GISTs studied. CONCLUSIONS: Good and bad prognosis for disease-free survival of patients based on reduced and elevated combined MMR phenotypic expression of the 2 histomorphologically distinct GADCs, could be explained by disease-associated emergence of genomic MMR alterations in the tumor. The impact of synchronous GISTs with common intermediate MMR phenotypes on patient survival is rather incidental and secondary to predominating GADCs.

Use of albumin polymers during breast cancer surgery improves postoperative seroma outcome.

The effect of an albumin polymer instillation (Bioglue® Cryolife, Inc., Kenneaw, GA, USA) during breast cancer surgery on postoperative seroma formation was evaluated. Two groups of 34 consecutive patients, treated during operation with and without polymer, were followed postoperatively by weekly ultrasound and clinical evaluation. Seroma was aspirated when the volume exceeded 250 mL. Statistical comparison between 33 of the patients with adhesive- and 32 with non-adhesive-treated patients showed that the former patient group clearly outperformed the latter in production (p<0.001) and duration (p<0.01) of seroma. Seroma outcome depended on body mass index (BMI) (>30 & <30, p<0.007), not on patient age (p<0.240) or nodes ratio (p<0.613). Repeated aspirations were made in 37.5% non-polymer treated- and 21.21% polymer-treated patients. The findings demonstrated that use of albumin polymers during breast cancer surgery lowers postoperative seroma outcome significantly.

Low-Grade Appendiceal Mucinous Neoplasm Presenting as a Surgical Emergency: A Case Report.

We present the case of a female patient admitted to our University Hospital with acute abdominal pain mimicking an intraperitoneal septic condition caused possibly by acute appendicitis. CT and ultrasound scan showed a mass situated in the right iliac fossa. The patient was submitted to laparotomy and right hemicolectomy. The operative findings were suggestive of an appendiceal mucocele. The histology report revealed a low-grade appendiceal mucinous neoplasm. The patient had no clinical, biochemical or visual signs of disease recurrence 6 months postoperatively.

On the mechanism of phenotypic conversion of human cervical adenocarcinoma HeLa cells surviving infection by influenza B virus: potential implications for biological management of adenocarcinomas.

We infected HeLa cells with low (10(-9) units), medium (10(-6) units), and high (10(-2) units) influenza B titers and compared the resulting human papilloma virus (HPV), retinoic acid receptor alpha subunit (RARalpha) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA content of surviving infected hosts with that of their uninfected precursors by semi-quantitative reverse transcriptase/polymerase chain reaction amplification (RT/PCR). This comparison revealed a moderate and drastic dependence of HPV and RARalpha mRNA content, respectively, but a complete independence of GAPDH mRNA expression on viral titer. A mechanism of adoptive replacement of tolerable cellular with viral gene expression was proposed to explain these findings. We conclude that the reported ability of influenza B viruses to specifically target and eliminate the cervical adenocarcinoma HeLa cell line studied may find practical applications in biological cancer management.