Targeting cancer stem cells expressing an embryonic signature with anti-proteases to decrease their tumor potential.

Cancer stem cells (CSCs) are a specific subset of cancer cells that sustain tumor growth and dissemination. They might represent a significant treatment target to reduce malignant progression and prevent tumor recurrence. In solid tumors, several hierarchically organized CSC clones coexist, even within a single tumor. Among them, CSCs displaying an embryonic stem cell 'stemness' signature, based on the expression of Oct-4, Nanog and Sox2, are present in distinct high-grade tumor types associated with poor prognosis. We previously designed a model to isolate pure populations of these CSCs from distinct solid tumors and used it to screen for molecules showing selective toxicity for this type of CSC. Here we show that human immunodeficiency virus (HIV)-protease inhibitors (HIV-PIs) specifically target CSCs expressing an embryonic signature derived from tumors with distinct origins. They reduced proliferation in a dose-dependent manner with a higher specificity as compared with the total population of cancer cells and/or healthy stem cells, and they were efficient in inducing cell death. Lopinavir was the most effective HIV-PI among those tested. It reduced self-renewal and induced apoptosis of CSCs, subsequently impairing in vivo CSC-induced allograft formation. Two key pharmacophores in the LPV structure were also identified. They are responsible for the specificity of CSC targeting and also for the overall antitumoral activity. These results contribute to the identification of molecules presenting selective toxicity for CSCs expressing an embryonic stemness signature. This paves the way to promising therapeutic opportunities for patients suffering from solid cancer tumors of poor prognosis.

Pure and mixed mucinous carcinoma of the breast: fine needle aspiration cytology findings and review of the literature.

OBJECTIVE: Mucinous (colloid) breast carcinoma accounts for 1-6% of all breast cancer. It comprises pure mucinous tumours and mixed infiltrating ductal carcinomas with a mucinous component. As this latter mixed form has a worse prognosis than pure colloid carcinoma, making this diagnosis on fine needle aspiration cytology (FNAC) might influence the choice of treatment. METHODS: We report a consecutive series of 22 cases consisting of 17 mixed and five pure mucinous carcinomas diagnosed by cytology and verified on histopathology. Patients underwent FNAC at the one-stop clinic of our institution during a 7-year period of time. Cytological findings were evaluated by a semi-quantitative method and included percentage of smear surface occupied by mucin, shape of cell groupings, size and outline of tumour nuclei as well as presence or absence of nucleolus. RESULTS: Three of five pure mucinous carcinomas displayed at least two of the following features: abundant mucin, small nuclei and/or regular nuclear outlines. Sparse mucin, large nuclei, irregular nuclear outlines or the presence of nucleoli were found in 7 out of 17 mixed mucinous carcinomas but not in pure tumours. CONCLUSION: Cytopathological identification of patients with pure mucinous carcinomas may be performed in a limited number of cases.

[X-ray-induced DNA double-strand breaks after angiographic examinations of different anatomic regions]. / Strahleninduzierte DNA-Doppelstrangbrüche nach Angiografien verschiedener Körperregionen.

PURPOSE: The aim of this study was to investigate DNA double-strand breaks (DSBs) in blood lymphocytes as markers of the biological radiation effects in angiography patients. MATERIALS AND METHODS: The method is based on the phosphorylation of the histone variant H 2AX (gamma-H2AX) after formation of DSBs. Blood samples were collected before and up to 24 hours after exposure of 31 patients undergoing angiographies of different body regions. Blood lymphocytes were isolated, fixed, and stained with a specific gamma-H2AX antibody. Distinct foci representing DSBs were enumerated using fluorescence microscopy. Additional in-vitro experiments (10 - 100 mGy) were performed for evaluation of DBS repair. RESULTS: 15 minutes after the end of fluoroscopy values between 0.01 and 1.50 DSBs per cell were obtained. The DNA damage level normalized to the dose area product was 0.099 (cardiac angiographies), 0.053 (abdominal angiographies), 0.023 (pelvic/leg angiographies) and 0.004 excess foci/cell/mGym (2) (cerebrovascular angiographies). A linear correlation was found between gamma-H2AX foci levels and the dose area product (abdomen: R (2) = 0.96; pelvis/legs: R 2 = 0.71). In-vivo on average 46 % of DSBs disappeared within 1 hour and 70 % within 2.5 hours. CONCLUSION: gamma-H2AX immunofluorescence microscopy is a sensitive and reliable method for the determination of X-ray-induced DSBs during angiography. The DNA damage level depends on the dose, the exposed anatomic region, and the duration/fractionation of the X-ray exposure.

Comparative expression of Hedgehog ligands at different stages of prostate carcinoma progression.

Recent studies have revealed the potential involvement of Hedgehog (Hh) signalling in proliferation and invasive behaviour of prostate carcinoma (PCa). The aim of this study was to specify the role of Sonic Hh (Shh), Desert Hh (Dhh) and Indian Hh (Ihh) in the natural history of PCa. Hh ligands expression was compared in primary hormone-naive PCa (HNPC), hormone-treated PCa (HTPC) and hormone-refractory PCa (HRPC), using immunohistochemistry. Shh and Dhh were expressed by both epithelial and stromal cells of prostate tissues. Ihh was only expressed by stromal cells. For the three ligands, mRNA and immunostaining were not correlated. In HNPC, Shh epithelial expression was significantly associated with high Gleason scores (p = 0.03), metastatic lymph nodes (p = 0.004) and Dhh epithelial staining was associated with high pT stages (p = 0.003), seminal vesicle invasion (p = 0.03) and bladder neck invasion (p = 0.0008). Negative Shh staining in stromal cells was associated with high Gleason scores (p = 0.015), high pT stages (p = 0.01) and bladder neck invasion (p = 0.04). Concomitant absence of Shh and Dhh expression in stromal cells was an independent prognostic parameter for biological recurrence on multivariate analysis (p = 0.01). Epithelial expression of Shh and Dhh was increased in HTPC compared to HNPC (p = 0.02 and p = 0.04). Interestingly, in vitro, transcript analysis also showed increased expression of these 2 Hh ligands when androgen-sensitive LNCaP cells were maintained in androgen-free medium mimicking hormonal therapy. Epithelial expression of Dhh was increased (p < 0.0001) in HRPC compared to HNPC, while stromal expression of Shh and Dhh was decreased (p < 0.0001). In conclusion, the Hh signalling pathway is associated with pejorative pathological parameters in HNPC and is up-regulated in epithelial cells of HTPC and HRPC. Moreover, the lack of Hh molecules in stromal cells seems to be associated with invasive and hormone-refractory behaviours and suggests specific changes in stromal-epithelial crosstalks during PCa progression.

[Intracellular pharmacodynamic-pharmacokinetic of antiretroviral drugs]. / Pharmacodynamie plasmatique et intracellulaire des antirétroviraux anti-VIH.

Therapeutic Drug Monitoring (TDM) became these last years very attractive in clinical and fundamental researches for several reasons. In one hand, 21 antiretroviral drugs are currently used and pharmacological studies to understand drugs interactions and to choose the best drug combinations are needed. On the other hand, we observe treatment failure and numerous side effects such as lipodystropy in HIV treated patients. An inadequate intracellular concentration of the drug might be one of the main raisons of the ineffectiveness of therapy. Moreover, beside interindividual metabolism variations, unique posologies are still prescribed. Clinical trial uses a necessary statistic method, but it leads to one dose which should fit all subjects.We discuss here the importance ofTDM using both plasmatic and intracellular analyses to improve our antiretroviral drug understanding and try to lead to the personalization of treatment.

Platelet-aggregation inhibition and hemodynamic effects of beraprost sodium, a new oral prostacyclin derivative: a study in healthy male subjects.

The antiaggregation and hemodynamic effects of the new prostacyclin analogue beraprost sodium were investigated in a randomized, placebo-controlled, double-blind clinical trial of Latin-square design. Twelve healthy Caucasian males randomly received 8-day oral treatments of 20, 40, and 60 micrograms of beraprost sodium and a placebo. One-week washout periods followed each treatment. Pharmacokinetic and pharmacodynamic measurements were performed on days 1 and 8 for each period of treatment. All three doses of beraprost sodium significantly inhibited platelet aggregation on day 8 (compared with placebo) during the 1st h after drug intake. Incubation of the 60-micrograms beraprost sodium samples with ADP (2, 5, and 10 microM) and collagen (1.25 micrograms/mL) decreased platelet aggregation by 10, 19, 16, and 6 +/- 4% (mean +/- SE), respectively, compared with placebo. No significant hemodynamic effects on blood pressure, heart rate, and digital pulse were observed. The 60-micrograms dose of beraprost sodium did significantly decrease the IRZ index (which may reflect the left ventricular pre-ejection period) on days 1 and 8. Some subjects experienced headache and facial flushing, effects that were dose dependent and reversible. Beraprost sodium at 20- to 60-micrograms doses exerts platelet antiaggregation (day 8 of therapy) and slight hemodynamic (days 1 and 8 of treatment) effects in Caucasian males. Beraprost sodium hemodynamic effects and potential benefits in patients with cardiovascular disease should be explored further.

A dose-effect study of beraprost sodium in intermittent claudication.

We compared the efficacy and safety of three doses of beraprost sodium, an epoprostenol analogue, with placebo in the treatment of intermittent claudication (Fontaine's stage II). One hundred sixty-four patients were randomized to receive either placebo, 20 micrograms beraprost sodium (BPS60 group), 40 micrograms beraprost sodium (BPS120 group), or 60 micrograms beraprost sodium (BPS180 group) three times daily administered orally in a double-blind manner for 12 weeks. Treadmill exercise tests were performed twice during an initial selection phase (D-28 and D0) at week 10 (at trough beraprost concentration) and week 12 (at peak beraprost concentration) of the treatment phase. At week 10, all groups showed an increase in pain-free walking distance, and this distance was greatest in the BPS60 and BPS120 groups (p = 0.055). At week 12, a similar pattern was observed, and the difference was significant between the groups (p = 0.023). The most frequent adverse events reported were gastrointestinal disorders, headaches, skin disorders, and flushes. Patients who received either 60 or 120 micrograms of beraprost sodium daily had an increased pain-free walking distance. Further studies are required to investigate why the highest dose used (180 micrograms daily) showed lower efficacy. Having both vasodilating and antiplatelet properties and being able to increase pain-free walking distance in the short term, beraprost sodium is a promising drug for the treatment of intermittent claudication.

The degree of zinc phosphate cement coverage of complete crown preparations and its effect on crown retention.

This investigation examined the amount of retentive area covered by cement under complete coverage crowns and its effect on retention. Sixty crowns of self-cured acrylic resin were prepared on 60 identical brass dies and were divided into six groups of 10 crowns each according to different cement applications. The results showed that retention was dependent on the amount of retentive area covered by the cement. The amount of cement in the occlusal part of the cementation space did not affect retention.

Stress at work and mental health status among female hospital workers.

Relations between working conditions and mental health status of female hospital workers were studied in a sample of 1505 women: 43% were nurses, 32% auxiliaries, and 7% ancillary staff; 13% were other qualified health care staff, mainly head nurses; 5% had occupations other than direct health care; 63% worked on the morning, 20% on the afternoon, and 17% on the night shift. Data were collected at the annual routine medical visit by the occupational health practitioner, using self administered questionnaires and clinical assessments. Five health indicators were considered: a high score to the general health questionnaire (GHQ); fatigue; sleep impairment; use of antidepressants, sleeping pills, or sedatives; and diagnosis of psychiatric morbidity at clinical assessment. Four indices of stress at work were defined: job stress, mental load, insufficiency in internal training and discussion, and strain caused by schedule. The analysis was conducted by multiple logistic regression, controlling for type of occupation, shift, number of years of work in hospital, daily travel time to work, age, marital status, number of children, and wish to move house. Sleep impairment was mostly linked to shift and strain due to schedule. For all other indicators of mental health impairment and especially high GHQ scores, the adjusted odds ratios increased significantly with the levels of job stress, mental load, and strain due to schedule. This evidence of association between work involving an excessive cumulation of stress factors and mental wellbeing should be considered in interventions aimed at improving the working conditions of hospital workers.

[Multiple proximal coronaro-pulmonary fistulae. Review of the literature apropos of a new case]. / Fistules coronaro-pulmonaires proximales multiples. Revue de la littérature à propos d'un nouveau cas.

The authors report a new case of multiple proximal coronaro-pulmonary fistula between right coronary arteries, anterior interventricular artery and the trunk of the pulmonary artery, in a 64 year-old female patient with chest pain and a continuous murmur located in the third left intercostal space. The coronary steal is demonstrated by a myocardial scintigraphy during stress with return to normal after surgical ligation. A review of the literature enabled to find 33 cases of this major congenital anomaly of the coronary arteries, defined as an abnormal communication between at least two main coronary vessels and the trunk of the pulmonary artery. This results in a left-right shunt, usually minor without any repercussions on the right cavities and pulmonary pressures. The entire clinical, electrocardiographic, radiological, sonographic, scintigraphic, haemodynamic and angiographic picture is reported for these 33 cases. A physiopathological discussion is proposed. The course of this disease is usually favorable (only one case of myocardial infarction was published, without cardiac failure. Osler's endocarditis or sudden death); this seems to authorize simple monitoring as a logical therapeutic approach except when a myocardial ischemia secondary to coronary steal is demonstrated, imposing a surgical correction.