Targeting of preexisting and induced breast cancer stem cells with trastuzumab and trastuzumab emtansine (T-DM1).

The antibody trastuzumab (Herceptin) has substantially improved overall survival for patients with aggressive HER2-positive breast cancer. However, about 70% of all treated patients will experience relapse or disease progression. This may be related to an insufficient targeting of the CD44(high)CD24(low) breast cancer stem cell subset, which is not only highly resistant to chemotherapy and radiotherapy but also a poor target for trastuzumab due to low HER2 surface expression. Hence, we explored whether the new antibody-drug conjugate T-DM1, which consists of the potent chemotherapeutic DM1 coupled to trastuzumab, could improve the targeting of these tumor-initiating or metastasis-initiating cells. To this aim, primary HER2-overexpressing tumor cells as well as HER2-positive and HER2-negative breast cancer cell lines were treated with T-DM1, and effects on survival, colony formation, gene and protein expression as well as antibody internalization were assessed. This revealed that CD44(high)CD24(low)HER2(low) stem cell-like breast cancer cells show high endocytic activity and are thus particularly sensitive towards the antibody-drug conjugate T-DM1. Consequently, preexisting CD44(high)CD24(low) cancer stem cells were depleted by concentrations of T-DM1 that did not affect the bulk of the tumor cells. Likewise, colony formation was efficiently suppressed. Moreover, when tumor cells were cocultured with natural killer cells, antibody-dependent cell-mediated cytotoxicity was enhanced, and EMT-mediated induction of stem cell-like properties was prevented in differentiated tumor cells. Thus our study reveals an unanticipated targeting of stem cell-like breast cancer cells by T-DM1 that may contribute to the clinical efficacy of this recently approved antibody-drug conjugate.

[Severe maternal hepatopathies in the peripartum period--a case series with review of the literature focusing on pathogenesis and differential diagnosis]. / Lebensbedrohliche, maternale Leberaffektionen in der späten Schwangerschaft und im Wochenbett--eine Fallserie mit Überblick über Pathogenese und differenzialdiagnostische Abgrenzung.

BACKGROUND: A severe hepatopathy constitutes a serious threat during pregnancy and poses considerable challenges to the treating physicians. A broad spectrum of pregnancy-dependent or independent diseases like HELLP-syndrome, liver infection or acute fatty liver of pregnancy (AFLP) is characterized by these affections of the liver. In this study, we present a series of 3 cases with life-threatening hepatopathies and discuss the current state of the literature. A special focus is placed on pathogenesis and differential diagnosis. METHODOLOGY: Pathological, radiological and gynaecological/surgical procedures were performed according to the current German guidelines. Laboratory tests were conducted in the clinics' routine diagnostics section. The existing literature was reviewed via the US National Library of Medicine database "PubMed.gov". RESULTS: The first patient had been afflicted by a fulminant HELLP syndrome causing delivery after 32 weeks of pregnancy. Consecutively, she suffered a sub-total liver infarction followed by a severe coagulopathy and septic peritonitis. The second patient was diagnosed with HELLP syndrome at 36 weeks of pregnancy. The initially mild syndrome exacerbated after delivery leading to haemorrhagic shock and acute renal failure. In the third case, a woman with asymptomatic hepatitis B delivered in the 36th week of pregnancy. Post partum, her pre-existing condition worsened fulminantly resulting in sub-acute liver dystrophy and massive coagulopathy. DISCUSSION AND CONCLUSION: Whenever a hepatopathy occurs during pregnancy, several divergent diagnoses with severe implications and different aetiopathologies have to be considered. Diagnostic and therapeutic strategies have to be weighed quickly to enable a fast, interdisciplinary cooperation in order to prevent fatal outcomes.

Peptidomimetic GnRH antagonist AEZS-115 inhibits the growth of ovarian and endometrial cancer cells.

BACKGROUND: AEZS-115 (Aeterna Zentaris GmbH, Frankfurt/M, Germany) is an orally active peptidomimetic antagonist of gonadotropin-releasing hormone (GnRH). In various tumors, an autocrine growth-promoting loop has been described for GnRH. The current study evaluates the antitumor activity and mechanism of action of AEZS-115 in models of ovarian and endometrial cancer. MATERIALS AND METHODS: Human A2780, Acis2780, OAW-42, Ovcar-3, SKOV-3, Hec1A and Ishikawa cells were analyzed for GnRH receptor expression by reverse transcription polymerase chain reaction (RT-PCR). These cell lines were incubated with AEZS-115 at 1, 10 and 100 µM for 24 h, 48 h, and 72 h and the number of viable cells was determined. Fluorescence activated cell sorting (FACS) cell cycle analyses were performed with increasing concentrations of AEZS-115. Co-treatment experiments of cancer cells with GnRH antagonist cetrorelix and peptidomimetic GnRH antagonist AESZ-115 were carried out. RESULTS: A2780, Acis2780, OAW-42, Ovcar-3, SKOV-3, Hec1A and Ishikawa cells expressed GnRH receptors as demonstrated by RT-PCR. GnRH antagonist AEZS-115 inhibited growth of all cell lines in a dose- and time-dependent manner. Half maximal inhibitory concentration (IC(50)) values at 48 h of incubation were between 7 and 17.5 µM and for 72 h between 4.5 and 12.5 µM. IC(50) values for ovarian and endometrial cancer cells were rather similar. These results were obtained by tetrazolium salt [(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; MTT] assay and confirmed by additional crystal violet staining. Cell cycle FACS analysis revealed that AEZS-115 dose-dependently increased the fraction of apoptotic cells. Co-treatment experiments carried out with AEZS-115 and peptidic GnRH-antagonist cetrorelix suggest that the antitumor effect of AEZS-115 is not mediated by blockade of the GnRH receptor. CONCLUSION: GnRH antagonist AEZS-115 exhibited substantial antitumor activity in ovarian as well as endometrial cancer cell lines. However, this antitumor effect was not mediated by the tumoral GnRH receptors. To identify the mechanism of action of this compound, further research is warranted. Its in vitro antitumor activity makes AEZS-115 a promising candidate for in vivo studies of ovarian and endometrial cancer.

The post-reproductive Fallopian tube: better removed?

Recently, the distal Fallopian tube has attracted considerable attention not only as site of origin for serous cancer in women with BRCA mutations, but also as the anatomical location where the majority of serous ovarian cancers apparently develop. Consequently, the Fallopian tube may be the unique location where early 'ovarian' cancers can be found--which would contradict the long-standing impression that the ovaries and the Fallopian tubes are always simultaneously involved. Based on the dismal prognosis associated with ovarian cancer and our inability to screen for early-stage disease, we discuss the rationale for introducing salpinges-hysterectomy as new clinical standard for women in need of hysterectomy and further weigh the arguments for and against bilateral salpingectomy as a sterilization method. There is no known physiological benefit of retaining the post-reproductive Fallopian tube during hysterectomy or sterilization, especially as this does not affect ovarian hormone production. On the other hand, the consequences associated with a surgical menopause provide a rationale for preserving the ovaries in premenopausal women. Prophylactic removal of the Fallopian tubes during hysterectomy or sterilization would rule out any subsequent tubal pathology, such as hydrosalpinx, which is observed in up to 30% of women after hysterectomy. Moreover, this intervention is likely to offer considerable protection against later tumour development, even if the ovaries are retained. Thus, we recommend that any hysterectomy should be combined with salpingectomy. In addition, women over 35 years of age could also be offered bilateral salpingectomy as means of sterilization.

[Late interruption of pregnancy due to foetal disease: is an inductive method for the generation of ethical principles applicable?]. / Spätabbruch von Schwangerschaften bei fetalen Erkrankungen: Führt ein induktives Verfahren der Normgewinnung zu ethischer Klarheit?

BACKGROUND: The current study investigates if an inductive method for the generation of ethical principles can be applied to the crucial moral question if late interruption of pregnancy due to fetal disease is ethically adequate. METHODS: This method originates from the US American philosopher John Rawls and puts a group of so-called competent moral investigators in the beginning of the decision process. These competent moral investigators should be objective, tolerant and sensitive. Thus, real cases which lead to an intuitive, unanimous and clear decision of the competent moral investigators are analysed for the underlying ethical principles. The ethical principles thus detected are then applied to more complicated cases which could not be assessed clearly. RESULTS: In the current study, the case of foetal trisomy 18 and foetal palate cleft could be clearly judged with a yes and a no, respectively, with regard to an approval of late interruption of pregnancy. The underlying ethical principle leading to these decisions is the utilitaristic principle of minimising harm for mother and fetus. DISCUSSION: We then tried to apply this principle to a case of foetal trisomy 21, however, no clear decision for an approval or a disapproval of the interruption of pregnancy could be found as it was not possible to assess foetal interests.

The moral status of the embryo: an attempt at an analysis with the aid of David Hume's ethics.

This article applies the moral sentimentalism founded by David Hume to the moral status of the embryo. It will attempt to explain the paradoxical fact that in Germany abortion is common and socially accepted while preimplantation genetic diagnosis is banned with the aid of an approach based on moral sentimentalism. David Hume established the thesis that the human being is guided by the emotions and not by reason when making moral decisions. Scientific innovations often create a feeling of anxiety. Consequently, the initial moral judgment about it is negative. Due to this habit, the innovation is often accepted after a phase of indifference. This phenomenon has been observed in the case of heart transplantation, as well as for IVF. Consequently, the apparent contradiction in the varying degrees of the embryo's worthiness of protection in the womb and in the Petri dish is due to the simple fact that these are different stages of habituation. Therefore, the ethics of Hume cannot stipulate the embryo's moral status for once and for all; however, they can paradoxically raise the ongoing current debate to a more rational level through the insight that the underlying moral concepts are not based on reason alone.

Whole blood-derived miRNA profiles as potential new tools for ovarian cancer screening.

BACKGROUND: Screening is an unsolved problem for ovarian cancer (OvCA). As late detection is equivalent to poor prognosis, we analysed whether OvCA patients show diagnostically meaningful microRNA (miRNA) patterns in blood cells. METHODS: Blood-borne whole miRNome profiles from 24 patients with OvCA and 15 age- and sex-matched healthy controls were biostatistically evaluated. RESULTS: Student's t-test revealed 147 significantly deregulated miRNAs before and 4 after Benjamini-Hochberg adjustment. Although these included miRNAs already linked to OvCA (e.g., miR-16, miR-155), others had never before been connected to specific diseases. A bioinformatically calculated miRNA profile allowed for discrimination between blood samples of OvCA patients and healthy controls with an accuracy of >76%. When only cancers of the serous subtype were considered and compared with an extended control group (n=39), accuracy, specificity and sensitivity all increased to >85%. CONCLUSION: Our proof-of-principle study strengthens the hypothesis that neoplastic diseases generate characteristic miRNA fingerprints in blood cells. Still, the obtained OvCA-associated miRNA pattern is not yet sensitive and specific enough to permit the monitoring of disease progression or even preventive screening. Microarray-based miRNA profiling from peripheral blood could thus be combined with other markers to improve the notoriously difficult but important screening for OvCA.

Expression of transketolase-like 1 protein (TKTL1) in human endometrial cancer.

BACKGROUND: Malignant tumors metabolize glucose to lactate even in the presence of oxygen (aerobic glycolysis). The metabolic switch from oxidative glycolysis to non-oxidative fermentation of glucose and proteins performed by the tumor cells seems to be associated with TKTL1 and pAkt overexpression. Therefore the aim of the present study was to investigate the expression of TKTL1 and pAkt in human specimens of endometrial cancer as compared to benign endometrium. Additionally, expression of the glucose transporter GLUT1 was also investigated as aerobic glycolysis is associated with an increased need for glucose. MATERIALS AND METHODS: Levels of TKTL1, pAkt, and GLUT1 expression were immunhistochemically evaluated on paraffin embedded biopsy material from 10 benign and 41 malignant endometrial tissue samples. TKTL1 mRNA levels in the endometrial cancer cell lines Ishikawa and HEC-1A were evaluated by RT-PCR. RESULTS: Expression of TKTL1, GLUT1 and pAKT was significantly increased in endometrial carcinomas as compared to benign endometrial tissue. There was a significantly weaker TKTL1 expression in highly differentiated G1 tumors. In the human endometrial cancer cell lines Ishikawa and HEC-1A, TKTL1 mRNA was clearly detectable. CONCLUSION: The levels of TKTL1, GLUT1 and pAKT expression point to the glycolytic phenotype of malignant endometrial tissue. Given the pronounced TKTL1 expression across all different subtypes of endometrial cancer, this protein could serve as a target for future cancer treatments.