[Infiltrates of M2-Like Tumour-Associated Macrophages Are Adverse Prognostic Factor in Patients with Human Papillomavirus-Negative but Not in Human Papillomavirus-Positive Oropharyngeal Squamous Cell Carcinoma]

INTRODUCTION

Human papillomavirus with a high oncogenic potential (HR-HPV) is responsible for more than a half of squamous cell carcinomas of the oropharynx. The HR-HPV-dependent cases of this tumour have a better prognosis compared to the HR-HPV-negative cases, despite the usually more advanced disease at the time of diagnosis. In addition to genetic and epigenetic factors, the causes of this more favourable course of the disease are also seen in the participation of the tumour microenvironment, including the patient's immune system. Macrophages are one of the most important elements of the immunocompetent cells landscape that make up the tumour microenvironment. Traditionally, they are divided into 2 groups: inflammatory macrophages with the M1 phenotype and tumour-associated macrophages known as M2 phenotype macrophages.

OBJECTIVE

The aim of this study was to investigate the impact of the macrophage infiltrates intensity of the M1/M2 and M2 phenotype separately on the clinical outcome of patients with squamous cell carcinoma of the oropharynx (OPSCC), taking into account the HR-HPV status of tumours.

METHODS

The study involved 85 patients with OPSCC in which HR-HPV status in tumour tissue was determined using a double-check algorithm including the detection of viral DNA by RT-PCR method with subsequent confirmation of its biological activity by immunohistochemical demonstrating the P16INK4A protein overexpression. In each of the groups formed on the basis of HR-HPV status, macrophages were discriminated using CD68 and CD163 proteins as markers of pan-macrophage and M2 phenotype. The intensity of infiltrates was quantified by means of computer-assisted analysis in digital images of whole slides (virtual slides) separately in tumour tissue and stroma.

RESULTS

In HPV-positive patients, significantly more intense infiltration of both M1/M2 and M2 macrophages was found in the tumour stroma compared to HPV-negative patients. The infiltrates from both types of macrophages in the tumour tissue were less intense and did not differ between these groups. Intensive infiltration of CD68+ macrophages in the tumour front was associated with higher rate of nodal failures and a shorter nodal control in both HR-HPV groups. In the group of HR-HPV-negative patients, heavy infiltration of CD163+ macrophages was associated with significantly shorter: loco-regional control (LRC), metastasis-free survival and overall survival (OS). These parameters and prognosis in patients with scanty CD163+ infiltration were similar to favourable outcomes in HR-HPV-positive patients. The relative risk of local-regional recurrence, distant metastases and disease-related death in HR-HPV-negative patients with intense CD163+ infiltrates was, respectively, 4.7, 5.4 and 5.7 compared to patients with scanty infiltrates.

CONCLUSIONS

Tumours with a positive HR-HPV status demonstrate intense infiltrations of total pool M1/M2 and M2 macrophages. In the group of HPV-negative patients, intensive M1/M2 macrophage infiltrates correlate with higher risk of nodal failures, and intensive M2 infiltrates are an adverse prognostic factor for LRC, metastasis-free survival and OS.

A novel quantitative method of pten expression assessment in tumor tissue

Phosphatase and Tensin Homolog deleted on chromosome 10 (PTEN) gene is one of the most important tumor suppressor genes which is involved in the regulation of many signaling cascades (AKT/PKB and MAPK). Subtle changes in its activity lead to cancer susceptibility or aggressive tumor behaviour. Despite the diversity of mechanisms leading to PTEN inactivation, it is frequently associated with a decreased or complete loss of protein expression. About 20% decrease in PTEN expression could lead to the development of cancer. There have been no objective, quantitative methods of PTEN expression assessment that allow to measure the subtle variations of the protein concentration in a tissue-contextual manner. A new quantitative algorithm of immunostaining evaluation based on combination of color deconvolution and relative chromogen signal intensity was used in the study. The proposed algorithm was implemented in the popular ImageJ image analysis software and positively verified in cancer cell lines and tissue models as well as in the tissue samples of colorectal cancer (CRC) patients. The proposed quantitative method of PTEN expression assessment creates an alternative to currently available subjective methods and forms the basis for inter-case and inter-tissue comparisons. Using the algorithm it would be possible to identify three groups of patients with advanced colorectal cancer which could significantly differ in the overall survival. The research should be continued.

Abstract B044: Indoleamine-2,3-dioxygense, the receptors for transforming growth factor beta and interferon gamma in resected melanoma: The presence, co-relation to the clinical variables and prognostic value

Introduction: Indoleamine-2,3-dioxygense (IDO) is the enzyme that catalyzes the first step of tryptophan catabolism pathway in humans. It is known to impose a local immunosuppressive effect due to the hypersensitivity of lymphocytes to either the depletion of tryptophan itself or the accumulation of the metabolic intermediates of its catabolism pathway. Transforming growth factor beta (TGF-β) and interferon gamma (IFN-γ) are well-recognized positive regulators of IDO; both of them up-regulate IDO1 gene expression. Physiologically, IDO prevents the rejection of allogeneic fetus in pregnant females; yet tumors are known to overexpress IDO to avoid the immune response of the host. This study analyzes the prognostic significance of the three proteins in one of the strongest immunity-involved human tumors - the malignant melanoma (MM).

Material and methods: The material included paraffin-embedded specimen of 78 completely resected stage II-III primary skin MMs and 28 lymph nodes with metastases. Immunohistochemical staining was used to detect IDO directly. The material was not suitable for direct cytokine detection, therefore for TGF-β and IFN-γ immunohistochemical staining of their receptors was used (TGF-βR1 and IFN-γR1, respectively). A 4-step semiquantitative scale was used to assess the expression of the proteins (0/+/++/+++). For IDO, the pathologist's assessment was additionally validated by a computer-aided algorithm, which yielded percentage scores of staining intensity. The results were co-related to the clinical variables and the patient outcome, measured as disease-free (DFS), distant metastasis (or inoperable locoregional recurrence)-free (MFS) and overall survival (OS). Mann-Whitney and Wilcoxon tests were used for group comparison and Kaplan-Meier and Cox models were used for survival analysis.

Results: Median follow-up of the patients was 58.8 months (range: 5.6 – 129.5). IDO expression was significantly higher in patients who developed bone metastases compared to ones with other metastatic sites (p=0.04). On the contrary, IFN-γR1 expression levels were higher in patients who did not experience disease dissemination during the follow up than in those who did (p=0.008). High IFN-γR1 expression was associated with better median survival times (OS and MFS of +++ vs ++/+: 94 vs 38 months, p=0.01 and 93 vs 31 months, p=0.005, respectively) as well as with a reduced risk of death and dissemination in multivariate models (HR=0.48, p=0.004 and HR=0.49, p=0.003, respectively). Low IDO expression had a similar effect on unfavorable events' risk reduction, but only significant in patients with no initial lymph node involvement (HR=2.73, p=0.002; HR=4.2, p=0.0003 and HR=2.71, p=0.001 for OS, MFS and DFS, respectively). Mutual correlations of the expression levels of all proteins were only observed between TGF-βR1 and IFN-γR1 in metastatic lymph nodes (R=0.53, p<0.05). In an analysis of change in protein expression in matched pairs of skin tumors and metastatic lymph nodes from the same patient significant differences were observed for TGF-βR1 (p=0.004). A strong correlation was observed between semiquantitative and computer-aided IDO expression scores (R=0.62, p<0.05).

Conclusions: High IFN-γR1 expression is associated with better OS and MFS in melanoma patients independently of their tumor's clinical stage. Low IDO expression in N0 patients is associated with a reduced risk of death, dissemination and recurrence. TGF-βR1 and IFN-γR1 are moderately positively correlated in lymph node metastases and TGF-βR1 expression is different in skin tumors and lymph nodes of the same patient. Computer-aided image analysis is a promising validation method for immunohistochemical analysis and should be further developed.

Citation Format: Maciej J. Pelak, Dariusz Lange, Barbara Nikiel, Katarzyna M. Pecka, Miroslaw Snietura. Indoleamine-2,3-dioxygense, the receptors for transforming growth factor beta and interferon gamma in resected melanoma: The presence, co-relation to the clinical variables and prognostic value. [abstract]. In: Proceedings of the CRI-CIMT-EATI-AACR Inaugural International Cancer Immunotherapy Conference: Translating Science into Survival; September 16-19, 2015; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(1 Suppl):Abstract nr B044.

The presence and clinical implications of α-2,6-galactose-linked sialic acids in non-small-cell lung cancer brain metastases--preliminary study

Brain metastases (BM) in non-small-cell lung cancer (NSCLC) patients present an increasing clinical challenge. Identifying biomarkers which specifically identify patients at high risk of BM may improve their early diagnosis, which is crucial for surgical and radiotherapeutic treatment outcome. Alpha-2,6-sialyltransferase (α-2,6-ST) and the primary product of its activity, alpha-2,6-galactose-linked sialic acids (α-2,6-GalSA) have been found responsible for the adhesion of tumor cells to the brain vessels' endothelium and enabling their transmigration through the blood-brain barrier in brain metastatic tumors. The aim of the study was to investigate by histochemical method the presence and possible role of α-2,6-GalSA in the formation of brain metastasis in NSCLC. In the screening phase 76 metastatic brain tumors were stained for α-2,6-GalSA and the second phase involved an identical staining of 20 primary tumors of patients who had their primary tumors treated with surgery or definite radiochemotherapy yet who later developed BM. The results were compared to a control group of 22 patients treated with surgery for NSCLC and who survived 5 years without the recurrence of disease. Alpha-2,6-GalSA presence was found to be down-regulated in poorly differentiated tumor types, whereas majority of differentiated tumors overexpressed it. This was statistically significant for both BM and the primary tumors. The expression of α-2,6-GalSA remained stable in primary and metastatic tumor pairs, however, no statistically significant differences were observed between study and control groups. Within the study group, a higher α-2,6-GalSA expression was associated with better overall survival, but not all statistical models found this result significant. Further studies are recommended to validate these findings.

Potential role of human papilloma virus in the pathogenesis of gastric cancer

AIM: To demonstrate the presence and biological activity of human papilloma virus (HPV) in gastric cancer (GAC) tissues.

METHODS: The study involved 84 surgically treated patients with gastric adenocarcinoma, regardless of the clinical stage of the disease. The presence of HPV DNA of high oncogenic risk types in formalin-fixed, paraffin-embedded tumor samples was determined using quantitative polymerase chain reaction analysis. A stringent protocol of prevention of cross- and environmental contamination was applied during DNA isolation, and amplification, as well as confirmation of the biological activity of the virus in tumor cells, was implemented. The study utilized the Real-time High Risk HPV test, which detects the DNA of 14 HPV subtypes that are considered to have high oncogenic potential. The overexpression of the p16^INK4a protein assessed immunohistochemically was considered confirmation of the HPV infection.

RESULTS: Among the 89 patients initially included in the study group, diagnostic results were obtained for 84 individuals. In five cases, either the histopathological material was too scant to isolate the necessary amount of DNA, or the isolated DNA was significantly degraded, resulting in the failure of internal control amplification within the predefined number of 35 cycles. Those patients were excluded from further analysis. The amplification of HPV DNA was demonstrated in none of the 84 tissue samples; thus, all cases were considered to have a negative DNA status of highly oncogenic HPV subtypes. Immunohistochemical staining provided diagnostic results for all of the examined tissue samples, and excluded the accumulation of the p16^INK4a protein in tumor cells, thus confirming the lack of active HPV infection in all of the individuals.

CONCLUSION: The study does not confirm the presence or biological activity of HPV in tumor tissues. Thus, the relationship between GAC and HPV infection, in the Central European population seems doubtful.

Does human papilloma virus participate in colorectal carcinogenesis?

Colorectal cancer is one of the most commonly diagnosed neoplasms still associated with relatively high mortality. Viral infections are often mentioned among the neoplasm transformation risk factors. Incidence of human papilloma virus (HPV), associated with high oncogenic risk, in the large intestine and the meaning of its presence in the colorectal carcinogenesis are still not clear. The aim of the study was to show a presence of HPV in specimens of adenomatous polyps and colorectal cancer using the Q-PCR method. Fifty patients (32 M/18W, mean age 62.8 years) were enrolled in the study, for whom tissue samples were obtained. Study material involved paraffin blocks derived from samples collected by flexible sigmoidoscopy from 10 polyps and 10 large intestine adenocarcinomas and 30 paraffin blocks with specimens of surgically removed large intestine adenocarcinomas. Presence of HPV genome was confirmed by quantitative PCR method using commercially available Abbott RealTime High Risk HPV test. The test is able to detect 14 most prevalent high oncogenic risk subtypes of human papilloma virus. Status of HPV DNA was successfully assessed in all 50 samples. No HPV DNA was discovered in any of the tested samples. Presence of high oncogenic risk HPV subtypes in large intestine adenoma and adenocarcinoma seems to be very rare, and its dominating role in the pathogenesis of colorectal cancer, even if possible, is unlikely.

PTEN as a prognostic and predictive marker in postoperative radiotherapy for squamous cell cancer of the head and neck

Background

Tumor suppressor PTEN is known to control a variety of processes related to cell survival, proliferation, and growth. PTEN expression is considered as a prognostic factor in some human neoplasms like breast, prostate, and thyroid cancer.

Methodology/Principal Findings

In this study we analyzed the influence of PTEN expression on the outcome of a randomized clinical trial of conventional versus 7-days-a-week postoperative radiotherapy for squamous cell cancer of the head and neck. The patients with cancer of the oral cavity, oropharynx, and larynx were randomized to receive 63 Gy in fractions of 1.8 Gy given 5 days a week (CF) or 7 days a week (p-CAIR). Out of 279 patients enrolled in the study, 147 paraffin blocks were available for an immunohistochemical assessment of PTEN. To evaluate the prognostic value of PTEN expression and the effect of fractionation relative to PTEN, the data on the outcome of a randomized clinical trial were analyzed. Tumors with a high intensity of PTEN staining had significant gain in the loco-regional control (LRC) from p-CAIR (5-year LRC 92.7% vs. 70.8%, for p-CAIR vs. CF, p = 0.016, RR = 0.26). By contrast, tumors with low intensity of PTEN did not gain from p-CAIR (5-year LRC 56.2% vs. 47.2%, p = 0.49, RR = 0.94). The intensity of PTEN highly affected the LRC in a whole group of 147 patients (5-year LRC 80.9% vs. 52.3% for high vs. low PTEN, p = 0.0007, RR = 0.32). In multivariate Cox analysis, including neck node involvement, EGFR, nm23, Ki-67, p53, cyclin D1, tumor site and margins, PTEN remained an independent predictor of LRC (RR = 2.8 p = 0.004).

Conclusions/Significance

These results suggest that PTEN may serve as a potent prognostic and predictive marker in postoperative radiotherapy for high-risk squamous cell cancer of the head and neck.

Impact of HPV infection on the clinical outcome of p-CAIR trial in head and neck cancer

The purpose of the study was to analyse the influence of HPV infection on the outcome of a randomized clinical trial of conventional (CF) versus 7-days-a-week postoperative radiotherapy (p-CAIR) for squamous cell cancer of the head and neck (SCCHN). Between 2001 and 2004, 279 patients with high-risk SCC of the larynx or cancer of the oral cavity/oropharynx were randomized to receive 63 Gy in fractions of 1.8 Gy given 5 days a week or 7 days a week (Radiother Oncol 87:155-163, 2008). The presence of HPV DNA in 131 archival paraffin blocks was assessed with multiplex quantitative real-time PCR using five consensus primers for the conservative L1 region and molecular beacon probes targeting 14 high-risk HPV subtypes. Following the RT-PCR procedure, we could determine the presence and type of HPV16, HPV18 and the other 12 less frequent oncogenic subtypes. Out of 131 samples, 9 were positive for HPV infection (6.9%), all of them with HPV16 subtype. None of the 65 laryngeal tumours was HPV positive. The 5-year LRC in HPV-positive patients was 100%, compared to 58% in the HPV-negative group (p = 0.02, log-rank test). Amongst 122 patients with HPV-negative tumours, 5-year LRC was 50.3% in p-CF versus 65.2 in p-CAIR (p = 0.37). HPV infection was associated with low expression of EGFR and cyclin D. This study demonstrates a favourable outcome for HPV-positive patients with SCCHN treated with postoperative radiotherapy. While considering the small number of HPV+ tumours, the data set can be considered as hypothesis generating only, the outcome raises new questions on the necessity of aggressive postoperative treatment in HPV+ patients.

Influence of local peripheral temporary ischaemia on biochemical and histological effects in small intestine and serum of rats following abdominal irradiation

The local temporary ischaemia effect on radiation-induced lipid peroxidation, superoxide dismutase isoenzyme activities, and intestinal crypt number was estimated in male WAG-strain rats in vivo. The animals were irradiated in the abdomen area with doses of 2 Gy for ten consecutive days using a Philips 60Co source. The calculated dose rate was 0.595 Gy/min. Local temporary ischaemia was induced by clamping the tail base before each irradiation. The parameters evaluated were: TBA-RS level and enzymatic activities of CuZnSOD, MnSOD in serum and jejunum. The number of jejunum crypts was assigned as a histopathologic parameter. The results showed a clear protection by ischaemic preconditioning for crypt survival. The difference in the number of crypts in irradiated animals with and without local temporary ischaemia was statistically significant (Student's t-test P < 0.05). Also, significant enhancement of TBA-RS was observed in the serum of irradiated animals. Local temporary ischaemia application diminished the concentration of radiation- induced TBA-RS. The differences in the levels of TBA-RS in the serum were statistically significant (ANOVA P < 0.002). In contrast, there was no evident effect on the level of TBA-RS in tissue homogenates in any investigated groups. Some fluctuation of CuZnSOD isoenzyme activity in intestinal tissue was noted; however, the differences were not significant. Local temporary ischaemia had no influence on Mn- SOD activity in serum, and in both irradiated groups the behaviour of this isoenzyme was similar. Also, there were no differences in MnSOD activity measured in tissue homogenates. These findings support results of our previous in vivo studies, suggesting that local temporary ischaemia can prevent oxidative effects of fractionated radiotherapy.

Intracellular distribution of Photofrin in malignant and normal endothelial cell lines

Compared to current treatments including surgery, radiation therapy, and chemotherapy, PDT offers the advantage of an effective and selective method of destroying diseased tissues without damaging surrounding healthy tissues. One of the aspects of antitumour effectiveness of PDT is related to the distribution of photosensitizing drugs. The localization of photosensitizers in cytoplasmic organelles during PDT plays a major role in the cell destruction; therefore, intracellular localization of Ph in malignant and normal cells was investigated. The cell lines used throughout the study were: human malignant A549, MCF-7, Me45 and normal endothelial cell line HUV-EC-C. After incubation with Ph cells were examined using fluorescence and confocal microscopy to visualize the photosensitizer accumulation. For cytoplasm and mitochondria identification, cells were stained with CellTracker Green and MitoTracker Green, respectively. Distribution of Ph was different in malignant and normal cells and dependent on the incubation time. The maximal concentration of Ph in two malignant cell lines (A549 and MCF-7) was observed after 4 hours of incubation, and the most intensive signal was observed around the nuclear envelope. Intracellular distribution of Ph in the Me45 cell line showed that the fluorescence emitted by Ph overlaid that from MitoTracker. This indicates preferential accumulation of the sensitizer in mitochondria. Our results based on the mitochondrial localization support the idea that PDT can contribute to elimination of malignant cells by inducing apoptosis, which is of physiological significance.

Spectroscopic properties and photodynamic effects of new lipophilic porphyrin derivatives: efficacy, localisation and cell death pathways

Photodynamic therapy (PDT) and photodynamic diagnostics (PDD) of cancer are based on the use of non-toxic dyes (photosensitisers) in combination with harmless visible light. This paper reports physicochemical properties, cell uptake, localisation as well as photodynamic efficiency of two novel lipophilic porphyrin derivatives, suitable for use as PDT sensitisers. Both compounds are characterised by high quantum yield of singlet oxygen generation which was measured by time-resolved phosphorescence. Photodynamic in vitro studies were conducted on three cancer cell lines. Results of cell survival tests showed negligible dark cytotoxicity but high phototoxicity. The results also indicate that cell death is dependent on energy dose and time following light exposure. Using confocal laser scanning microscopy both compounds were found to localise in the cytoplasm around the nucleus of the tumour cells. The mode of cell death was evaluated based on the morphological changes after differential staining. In summary, good photostability, high quantum yield of singlet oxygen and biological effectiveness indicate that the examined lipophilic porphyrin derivatives offer quite interesting prospects of photodynamic therapy application.

Protective effect of local temporary ischemia depends on applied dose of radiation

The aim of this study was to verify hypothesis that protective effect of local temporary ischemia depends on dose of radiation. 56 male WAG-strain rats were used. Total body irradiation with 3 x 3 and 3 x 5 Gy was performed. Local temporary ischemia was induced by clamping the tail base. The biochemical parameters were the thiobarbituric acid-reactive substances (TBA-RS). In bone marrow smears the polychromatic erythrocyte (PCE) numbers were counted and the numbers of micronucleated PCEs were analyzed. In small intestines the numbers of crypts were calculated. The levels of TBA-RS in the serum of the animals irradiated with a 3 x 3 Gy dose were significantly different (P < 0.002). Also in animals irradiated with a dose of 3 x 3 Gy the numbers of intestinal crypts were different (P < 0.05). In animals irradiated with dose 3 x 5 Gy, for analyzed parameters differences did not achieve statistical significance. Local temporary ischaemia provides general protection against radiation damage for lower dose. This protective effect disappeared after applications of a higher dose of radiation.

Endodermal cyst of the cervical spinal cord with associated partial fusion of the vertebrae

A case of a 43-year-old woman with an intradural endodermal cyst at the C4 spinal cord level is presented. The lesion manifested with progressive neck pain and weakness of lower extremities. The presumptive diagnosis of extramedullary benign cystic lesion was established after MRI examination. Coexisting partial fusion of the C5-C6 vertebral bodies was found on X-ray films. The patient was cured by resection of the cyst wall, performed by laminectomy. Pathological examination revealed a cyst wall lined with ciliated cuboidal cells, resembling the respiratory epithelium. Immunohistochemistry demonstrated cytokeratin and epithelial membrane antigen expression in the lining of the cyst. Endodermal cyst should be considered in the differential diagnosis of intraspinal cystic lesions, especially those associated with vertebral anomalies.

Inhibitory effect of local ischaemic preconditioning in total body irradiated rats

The aim of this study was to explore the relationship between local ischaemic preconditioning and the effectiveness of fractionated radiotherapy. The rat serum, bone marrow, and small intestine were examined for oxidative changes induced by total body irradiation with gamma rays with applied local ischaemic preconditioning immediately before irradiation. Serum concentrations of TBA-RS examined 12 hours after the last irradiation did not reveal any differences among the groups of animals analyzed. Twenty-four hours after the last dose of irradiation, the serum concentrations of TBA-RS varied in particular groups (P<0.0001). The concentration of triglycerides in the serum of local preconditioned ischaemia and irradiated animals showed a reversed shape similar to the TBA-RS fluctuation (P<0.003). The level of uric acid in the serum of animals treated only with radiation is slightly higher than the level of this acid in the serum of the local preconditioned ischaemia radiation group (P<0.58). The number of bone marrow polychromatic erythrocytes did not appear to differ substantially in both irradiated groups. At the first 12 hours after irradiation, the frequency of micronucleated polychromatic erythrocytes is significantly different in the bone marrow of both groups either in combination with ischaemic preconditioned radiation or with radiation alone (P<0.0002). In irradiated animals without ischaemic preconditioning, on the 3rd day after irradiation the number of crypts increased and in the next days decreased achieving the level of the control group on the 7th day. Irradiated rats with local ischaemic preconditioning did not reveal an increase in the number of crypts. The difference was statistically significant (P<0.05). These data indicate that the local ischaemic preconditioning modifies the radiation peroxidising effects through inhibition of free radical-dependent lipid peroxidation and, probably, other unrecognized mechanisms.

DNA ploidy assessment method applied to primary breast carcinoma FNA biopsies

The goal of our study was to assess suitability of FNA biopsy material as a source of samples (cell suspension) for DNA ploidy assessment in neoplastic tumors using flow cytometry. DNA ploidy is an established prognostic factor in many types of cancers. Aneuploid breast tumors are characterized by increased aggressiveness which manifests itself through rapid local progression and metastatic spread. Investigated specimens were breast cancer FNA biopsy cell suspensions. Measurements were performed using flow cytometry. Material studied comprised 143 cases analyzed in 1999-2000. We found in this group 101 carcinoma cases with aneuploid type and 42 cases of primary breast carcinoma with diploid type of cell cycle. Immunocytochemical assesssment of estrogen receptor and progesterone receptor status was performed in group of 105 cases. DNA ploidy was compared to receptor status of the investigated cells. DNA aneuploidy correlated with weak or no reaction for the presence of estrogen and progesterone receptors. Our study demonstrates the suitability of DNA ploidy assessment method applied to cytological material from FNA biopsies.

Post-stenting intravascular brachytherapy trials on hypercholesterolemic rabbits using 32P liquid sources: implications for prevention of in-stent restenosis

PURPOSE

Liquid sources of radiation delivered in angioplasty balloons may be a convenient self-centering device used for prevention of in-stent restenosis. To test the effectiveness of this method an intravascular brachytherapy study was performed using 32P liquid sources in an animal model.

METHODS

The radial dose distribution around angioplasty balloons filled with solutions of Na 2H 32PO 4 was calibrated by thermoluminescence dosimetry. The animal experiments were performed in rabbits with induced hypercholesterolemia. The balloons containing 32P were introduced into iliac arteries immediately after stent implantation. Estimated 7-49 Gy doses required 30-100 min irradiations. Radiation effects were evaluated by comparing the thickness of various components of the artery wall.

RESULTS

Doses of 7, 12, 16 or 49 Gy on the internal artery surface required 30-100 min of irradiation. The dose of 49 Gy at "zero" distance corresponding to 16 Gy at 1.0 mm from the balloon surface reduced hypertrophy in every layer of the arterial wall: in the intima the cross-sectional areas were 0.13 versus 0.91 mm 2, in the media were 0.5 versus 0.46 mm 2 and in the adventitia were 0.04 versus 0.3 mm 2 (p <0.05). A dose of 7 Gy at the balloon surface produced adverse irradiation effects: the intimal area of the artery was 2.087 versus 0.857 mm 2, the medial area was 0.59 versus 0.282 mm 2 and the adventitial area was 0.033 versus 0.209 mm 2 in treated and control arteries, respectively.

CONCLUSION

Application of a 49 Gy irradiation dose to the internal arterial surface effectively prevented in-stent restenosis.

Effect of phosphoramidon on brain tissue angiogenesis in the chronic phase of vasospasm after subarachnoid hemorrhage in the rat

BACKGROUND

Subarachnoid hemorrhage (SAH) frequently leads to prolonged cerebral vasospasm resulting in vascular pathology due to endothelial cell ischemia and neuronal hypoxia. Posthemorrhagic vasospasm can be counteracted by the administration of phosphoramidon, which blocks the endothelin converting enzyme (ECE) responsible for the conversion of big endothelin into a fully active ET1 peptide. The aim of the study was to determine the effect of chronic vasospasm after SAH on angiogenesis and the effect on this process of endothelin-1, the main causative factor in vasospasm.

MATERIAL AND METHODS

Male Wistar rats were examined. Seven days after cannulation of the cisterna magna, blood was administered to induce SAH. The ECE inhibitor phosphoramidon was administered in a dose of 40 nmol in 50 microl of cerebrospinal fluid three times: 20 min before SAH, 60 min after SAH, and 24 hours after SAH. The brains were removed 48 hours later for histological evaluation. The vascular surface density was measured in cerebral hemisphere sections (at the level of the dorsal part of the hippocampus) and brainstem sections (1/2 of the pons).

CONCLUSION

Increased angiogenesis was observed in the cerebral hemispheres after SAH. The administration of phosphoramidon inhibits angiogenesis in cerebral hemispheres after SAH.

Cerebral angiogenesis after subarachnoid hemorrhage (SAH) and endothelin receptor blockage with BQ-123 antagonist in rats

The aim of the study was to determine the effect of chronic vasospasm after SAH on angiogenesis and the effect of endothelin-1, the main causative factor in vasospasm, on this process. Male Wistar rats, 220-250 g, were examined. Seven days after cannulation of the cisterna magna (CM), a 100 microl dose of non-heparinized blood was administered to induce SAH. Sham SAH (aSAH) was induced by intracisternal injection of 100 microl of artificial cerebrospinal fluid. Endothelin receptor antagonist BQ-123 in a dose of 40 nmol in 50 microl of cerebrospinal fluid was given three times: 20 min. before SAH and aSAH, 60 min and 24 hours after SAH and aSAH. The same pattern of BQ-123 administration was used in the nonSAH group. The brains were removed 48 hours later for histological evaluation. Vascular surface density was measured in cerebral hemisphere sections (at the level of the dorsal part of the hippocampus) and brain stem sections (1/2 of the pons). An increase in angiogenesis was observed after SAH, compared to control values. The administration of BQ-123, a specific endothelin receptor blocker inhibits angiogenesis in cerebral hemispheres after SAH.