@article{DiessnerBruttelBeckeretal.2013, author = {Diessner, Joachim and Bruttel, Valentin and Becker, Kathrin and Pawlik, Miriam and Stein, Roland and H{\"a}usler, Sebastian and Dietl, Johannes and Wischhusen, J{\"o}rg and H{\"o}nig, Arnd}, title = {Targeting breast cancer stem cells with HER2-specific antibodies and natural killer cells}, series = {American Journal of Cancer Research}, volume = {3}, journal = {American Journal of Cancer Research}, number = {2}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128633}, pages = {221-220}, year = {2013}, abstract = {Breast cancer is the most common cancer among women worldwide. Every year, nearly 1.4 million new cases of breast cancer are diagnosed, and about 450.000 women die of the disease. Approximately 15-25\% of breast cancer cases exhibit increased quantities of the trans-membrane receptor tyrosine kinase human epidermal growth factor receptor 2 (HER2) on the tumor cell surface. Previous studies showed that blockade of this HER2 proto-oncogene with the antibody trastuzumab substantially improved the overall survival of patients with this aggressive type of breast cancer. Recruitment of natural killer (NK) cells and subsequent induction of antibody-dependent cell-mediated cytotoxicity (ADCC) contributed to this beneficial effect. We hypothesized that antibody binding to HER2-positive breast cancer cells and thus ADCC might be further improved by synergistically applying two different HER2-specific antibodies, trastuzumab and pertuzumab. We found that tumor cell killing via ADCC was increased when the combination of trastuzumab, pertuzumab, and NK cells was applied to HER2-positive breast cancer cells, as compared to the extent of ADCC induced by a single antibody. Furthermore, a subset of \(CD44^{high}CD24^{low}HER2^{low}\) cells, which possessed characteristics of cancer stem cells, could be targeted more efficiently by the combination of two HER2-specific antibodies compared to the efficiency of one antibody. These in vitro results demonstrated the immunotherapeutic benefit achieved by the combined application of trastuzumab and pertuzumab. These findings are consistent with the positive results of the clinical studies, CLEOPATRA and NEOSPHERE, conducted with patients that had HER2-positive breast cancer. Compared to a single antibody treatment, the combined application of trastuzumab and pertuzumab showed a stronger ADCC effect and improved the targeting of breast cancer stem cells.}, language = {en} } @article{HaeuslerdelBarrioDiessneretal.2014, author = {H{\"a}usler, Sebastian F. M. and del Barrio, Itsaso Montalb{\´a}n and Diessner, Joachim and Stein, Roland G. and Strohschein, Jenny and H{\"o}nig, Arnd and Dietl, Johannes and Wischhusen, J{\"o}rg}, title = {Anti-CD39 and anti-CD73 antibodies A1 and 7G2 improve targeted therapy in ovarian cancer by blocking adenosine-dependent immune evasion}, series = {American Journal of Translational Research}, volume = {6}, journal = {American Journal of Translational Research}, number = {2}, issn = {1943-8141}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-120016}, pages = {129-139}, year = {2014}, abstract = {The ectonucleotidases CD39 and CD73 degrade ATP to adenosine which inhibits immune responses via the \(A_{2A}\) adenosine receptor (ADORA2A) on T and NK cells. The current study investigates the potential therapeutic use of the specific anti CD39- and anti CD73-antibodies A1 (CD39) and 7G2 (CD73) as these two ectonucleotidases are overexpressed in ovarian cancer (OvCA). As expected, NK cell cytotoxicity against the human ovarian cancer cell lines OAW-42 or SK-OV-3 was significantly increased in the presence of A1 or 7G2 antibody. While this might partly be due to antibody-dependent cell-mediated cytotoxicity, a luciferase-dependent assay for quantifying biologically active adenosine further showed that A1 and 7G2 can inhibit CD39 and CD73-dependent adenosine-generation. In turn, the reduction in adenosine levels achieved by addition of A1 and 7G2 to OAW-42 or SK-OV-3 cells was found to de-inhibit the proliferation of \(CD4^+\) T cells in coculture with OvCA cells. Likewise, blocking of CD39 and CD73 on OvCA cells via A1 and 7G2 led to an increased cytotoxicity of alloreactive primed T cells. Thus, antibodies like A1 and 7G2 could improve targeted therapy in ovarian cancer not only by specifically labeling overexpressed antigens but also by blocking adenosine-dependent immune evasion in this immunogenic malignancy.}, language = {en} } @article{MontalbandelBarrioPenskiSchlahsaetal.2016, author = {Montalb{\´a}n del Barrio, Itsaso and Penski, Cornelia and Schlahsa, Laura and Stein, Roland G. and Diessner, Joachim and W{\"o}ckel, Achim and Dietl, Johannes and Lutz, Manfred B. and Mittelbronn, Michel and Wischhusen, J{\"o}rg and H{\"a}usler, Sebastian F. M.}, title = {Adenosine-generating ovarian cancer cells attract myeloid cells which differentiate into adenosine-generating tumor associated macrophages - a self-amplifying, CD39- and CD73-dependent mechanism for tumor immune escape}, series = {Journal for ImmunoTherapy of Cancer}, volume = {4}, journal = {Journal for ImmunoTherapy of Cancer}, number = {49}, doi = {10.1186/s40425-016-0154-9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-146624}, year = {2016}, abstract = {Background Ovarian cancer (OvCA) tissues show abundant expression of the ectonucleotidases CD39 and CD73 which generate immunomodulatory adenosine, thereby inhibiting cytotoxic lymphocytes. Little, however, is known about the effect of adenosine on myeloid cells. Considering that tumor associated macrophages (TAM) and myeloid-derived suppressor cells (MDSC) constitute up to 20 \% of OvCA tissue, we investigated the effect of adenosine on myeloid cells and explored a possible contribution of myeloid cells to adenosine generation in vitro and ex vivo. Methods Monocytes were used as human blood-derived myeloid cells. After co-incubation with SK-OV-3 or OAW-42 OvCA cells, monocyte migration was determined in transwell assays. For conversion into M2-polarized "TAM-like" macrophages, monocytes were co-incubated with OAW-42 cells. Ex vivo TAMs were obtained from OvCA ascites. Macrophage phenotypes were investigated by intracellular staining for IL-10 and IL-12. CD39 and CD73 expression were assessed by FACS analysis both on in vitro-induced TAM-like macrophages and on ascites-derived ex situ-TAMs. Myeloid cells in solid tumor tissue were analyzed by immunohistochemistry. Generation of biologically active adenosine by TAM-like macrophages was measured in luciferase-based reporter assays. Functional effects of adenosine were investigated in proliferation-experiments with CD4+ T cells and specific inhibitors. Results When CD39 or CD73 activity on OvCA cells were blocked, the migration of monocytes towards OvCA cells was significantly decreased. In vivo, myeloid cells in solid ovarian cancer tissue were found to express CD39 whereas CD73 was mainly detected on stromal fibroblasts. Ex situ-TAMs and in vitro differentiated TAM-like cells, however, upregulated the expression of CD39 and CD73 compared to monocytes or M1 macrophages. Expression of ectonucleotidases also translated into increased levels of biologically active adenosine. Accordingly, co-incubation with these TAMs suppressed CD4+ T cell proliferation which could be rescued via blockade of CD39 or CD73. Conclusion Adenosine generated by OvCA cells likely contributes to the recruitment of TAMs which further amplify adenosine-dependent immunosuppression via additional ectonucleotidase activity. In solid ovarian cancer tissue, TAMs express CD39 while CD73 is found on stromal fibroblasts. Accordingly, small molecule inhibitors of CD39 or CD73 could improve immune responses in ovarian cancer.}, language = {en} } @article{SteinWollschlaegerKreienbergetal.2016, author = {Stein, Roland Gregor and Wollschl{\"a}ger, Daniel and Kreienberg, Rolf and Janni, Wolfgang and Wischnewsky, Manfred and Diessner, Joachim and St{\"u}ber, Tanja and Bartmann, Catharina and Krockenberger, Mathias and Wischhusen, J{\"o}rg and W{\"o}ckel, Achim and Blettner, Maria and Schwentner, Lukas}, title = {The impact of breast cancer biological subtyping on tumor size assessment by ultrasound and mammography - a retrospective multicenter cohort study of 6543 primary breast cancer patients}, series = {BMC Cancer}, volume = {16}, journal = {BMC Cancer}, number = {549}, doi = {10.1186/s12885-016-2426-7}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-161050}, year = {2016}, abstract = {Background Mammography and ultrasound are the gold standard imaging techniques for preoperative assessment and for monitoring the efficacy of neoadjuvant chemotherapy in breast cancer. Maximum accuracy in predicting pathological tumor size non-invasively is critical for individualized therapy and surgical planning. We therefore aimed to assess the accuracy of tumor size measurement by ultrasound and mammography in a multicentered health services research study. Methods We retrospectively analyzed data from 6543 patients with unifocal, unilateral primary breast cancer. The maximum tumor diameter was measured by ultrasound and/or mammographic imaging. All measurements were compared to final tumor diameter determined by postoperative histopathological examination. We compared the precision of each imaging method across different patient subgroups as well as the method-specific accuracy in each patient subgroup. Results Overall, the correlation with histology was 0.61 for mammography and 0.60 for ultrasound. Both correlations were higher in pT2 cancers than in pT1 and pT3. Ultrasound as well as mammography revealed a significantly higher correlation with histology in invasive ductal compared to lobular cancers (p < 0.01). For invasive lobular cancers, the mammography showed better correlation with histology than ultrasound (p = 0.01), whereas there was no such advantage for invasive ductal cancers. Ultrasound was significantly superior for HR negative cancers (p < 0.001). HER2/neu positive cancers were also more precisely assessed by ultrasound (p < 0.001). The size of HER2/neu negative cancers could be more accurately predicted by mammography (p < 0.001). Conclusion This multicentered health services research approach demonstrates that predicting tumor size by mammography and ultrasound provides accurate results. Biological tumor features do, however, affect the diagnostic precision.}, language = {en} }