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Targeting self-renewal and tumorigenicity has been proposed as a potential strategy against cancer stem cells (CSCs). Epigenetic proteins are key modulators of gene expression and cancer development contributing to regulation and maintenance of self-renewal and tumorigenicity. Here, we have screened a small-molecule epigenetic inhibitor library using 3D in vitro models in order to determine potential epigenetic targets associated with self-renewal and tumorigenicity in Canine Mammary Cancer (CMC) cells. We identified inhibition of BET proteins as a promising strategy to inhibit CMC colonies and tumorspheres formation. Low doses of (+)-JQ1 were able to downregulate important genes associated to self-renewal pathways such as WNT, NOTCH, Hedgehog, PI3K/AKT/mTOR, EGF receptor and FGF receptor in CMC tumorspheres. In addition, we observed downregulation of ZEB2, a transcription factor important for the maintenance of self-renewal in canine mammary cancer cells. Furthermore, low doses of (+)-JQ1 were not cytotoxic in CMC cells cultured in 2D in vitro models but induced G2/M cell cycle arrest accompanied by upregulation of G2/M checkpoint-associated genes including BTG2 and CCNG2. Our work indicates the BET inhibition as a new strategy for canine mammary cancers by modulating the self-renewal phenotype in tumorigenic cells such as CSCs.
Purpose: The WSG-PRIMe Study prospectively evaluated the impact of the 70-gene signature MammaPrint® (MP) and the 80-gene molecular subtyping assay BluePrint® on clinical therapy decisions in luminal early breast cancer.
Methods: 452 hormone receptor (HR)-positive and HER2-negative patients were recruited (N0, N1). Physicians provided initial therapy recommendations based on clinicopathological factors. After prospective risk classification by MammaPrint/BluePrint was revealed, post-test treatment recommendations and actual treatment were recorded. Decisional Conflict and anxiety were measured by questionnaires.
Results: Post-test switch (in chemotherapy (CT) recommendation) occurred in 29.1% of cases. Overall, physician adherence to MP risk assessment was 92.3% for low-risk and 94.3% for high-risk MP scores. Adherence was remarkably high in “discordant” groups: 74.7% of physicians initially recommending CT switched to CT omission following low-risk MP scores; conversely, 88.9% of physicians initially recommending CT omission switched to CT recommendations following high-risk MP scores. Most patients (99.2%) recommended to forgo CT post-test and 21.3% of patients with post-test CT recommendations did not undergo CT; among MP low-risk patients with pre-test and post-test CT recommendations, 40% did not actually undergo CT. Luminal subtype assessment by BluePrint was discordant with IHC assessment in 34% of patients. Patients’ State Anxiety scores improved significantly overall, particularly in MP low-risk patients. Trait Anxiety scores increased slightly in MP high risk and decreased slightly in MP low-risk patients.
Conclusions: MammaPrint and BluePrint test results strongly impacted physicians’ therapy decisions in luminal EBC with up to three involved lymph nodes. The high adherence to genetically determined risk assessment represents a key prerequisite for achieving a personalized cost-effective approach to disease management of early breast cancer.
While aberrant cells are routinely recognized and removed by immune cells, tumors eventually escape innate immune responses. Infiltrating immune cells are even corrupted by the tumor to acquire a tumor-supporting phenotype. In line, tumor-associated macrophages are well-characterized to promote tumor progression and high levels of tumor-infiltrating macrophages are a poor prognostic marker in breast cancer. Here, we aimed to further decipher the influence of macrophages on breast tumor cells and determined global gene expression changes in three-dimensional tumor spheroids upon infiltration of macrophages. While various tumor-associated mRNAs were upregulated, expression of the cytochrome P450 family member CYP1A1 was markedly attenuated. Repression of CYP1A1 in tumor cells was elicited by a macrophage-shaped tumor microenvironment rather than by direct tumor cell-macrophage contacts. In line with changes in RNA expression profiles, macrophages enhanced proliferation of the tumor cells. Enhanced proliferation and macrophage presence further correlated with reduced CYP1A1 expression in patient tumors when compared with normal tissue. These findings are of interest in the context of combinatory therapeutic approaches involving cytotoxic and immune-modulatory compounds.
The goal of this study was to identify a novel target for antibody-drug conjugate (ADC) development in triple negative breast cancer (TNBC), which has limited treatment options, using gene expression datasets and in vitro siRNA/CRISPR and in vivo functional assays. We analyzed 4467 breast cancers and identified GABRP as top expressed gene in TNBC with low expression in most normal tissues. GABRP protein was localized to cell membrane with broad range of receptors/cell (815–53,714) and expressed by nearly half of breast cancers tissues. GABRP gene knockdown inhibited TNBC cell growth and colony formation in vitro and growth of MDA-MB-468 xenografts in nude mice. Commercially available anti-GABRP antibody (5–100 μg/ml) or de novo generated Fabs (20 μg/ml) inhibited TNBC cell growth in vitro. The same antibody conjugated to mertansine (DM1) also showed significant anticancer activity at nanomolar concentrations. Our results indicate that GABRP is a potential novel therapeutic target for ADC development.
Neoadjuvant systemic chemotherapy is a possible therapeutic approach for the treatment of locally advanced operable, primarily non-operable or inflammatory breast cancer. Neoadjuvant systemic chemotherapy is an option for breast cancer patients who would require adjuvant chemotherapy otherwise based on clinical and histological examination and imaging. The use of neoadjuvant systemic therapy in operable breast cancer is currently increasing because of its advantages that include higher rates of breast conserving surgery and the possibility of measuring early in-vivo response to systemic treatment. The timing of axillary sentinel lymph node diagnosis (i.e. before or after neoadjuvant chemotherapy) is critical in that it may influence the likelihood of axillary preservation. It is not yet clear if neoadjuvant therapy might improve outcomes in certain subgroups of breast cancer patients. Neoadjuvant treatment modalities require a close collaboration between oncology professionals, including surgeons, gynecologists, medical oncologists, radiation oncologists, radiologists and pathologists. The most important parameter for treatment success and improved overall survival is the achievement of a pathologic complete response (pCR), although the role of pCR in patients with luminal A like tumours might be less informative. Identification of patient subgroups with high pCR rates may allow less invasive surgical or radiological interventions. Patients not achieving a pCR may be candidates for postoperative clinical trials exploring novel systemic treatments.
Background: Breast cancer (BC) is the most frequent female cancer and preferentially metastasizes to bone. The transcription factor TGFB-induced factor homeobox 1 (TGIF) is involved in bone metabolism. However, it is not yet known whether TGIF is associated with BC bone metastasis or patient outcome and thus of potential interest. Methods: TGIF expression was analyzed by immunohistochemistry in 1197 formalin-fixed, paraffin-embedded tissue samples from BC patients treated in the GAIN (German Adjuvant Intergroup Node-Positive) study with two adjuvant dose-dense schedules of chemotherapy with or without bisphosphonate ibandronate. TGIF expression was categorized into negative/low and moderate/strong staining. Endpoints were disease-free survival (DFS), overall survival (OS) and time to primary bone metastasis as first site of relapse (TTPBM). Results: We found associations of higher TGIF protein expression with smaller tumor size (p= 0.015), well differentiated phenotype (p< 0.001) and estrogen receptor (ER)-positive BC (p< 0.001). Patients with higher TGIF expression levels showed a significantly longer disease-free (DFS: HR 0.75 [95%CI 0.59–0.95], log-rank p=0.019) and overall survival (OS: HR 0.69 [95%CI 0.50–0.94], log-rank p= 0.019), but no association with TTPBM (HR 0.77 [95%CI 0.51–1.16]; p= 0.213). Univariate analysis in molecular subgroups emphasized that elevated TGIF expression was prognostic for both DFS and OS in ER-positive BC patients (DFS: HR 0.68 [95%CI 0.51–0.91]; log-rank p= 0.009, interaction p= 0.130; OS: HR 0.60 [95%CI 0.41–0.88], log-rank p= 0.008, interaction p= 0.107) and in the HER2-negative subgroup (DFS:HR 0.67 [95%CI 0.50–0.88], log-rank p= 0.004, interaction p= 0.034; OS: HR 0.57 [95%CI 0.40–0.81], log-rank p= 0.002, interaction p= 0.015). Conclusions: Our results suggest that moderate to high TGIF expression is a common feature of breast cancer cells and that this is not associated with bone metastases as first site of relapse. However, a reduced expression is linked to tumor progression, especially in HER2-negative breast cancer.
Background: The focus of this study is to identify particular microRNA (miRNA) signatures in exosomes derived from plasma of 435 human epidermal growth factor receptor 2 (HER2)-positive and triple-negative (TN) subtypes of breast cancer (BC).
Methods: First, miRNA expression profiles were determined in exosomes derived from the plasma of 15 TNBC patients before neoadjuvant therapy using a quantitative TaqMan real-time PCR-based microRNA array card containing 384 different miRNAs. Forty-five miRNAs associated with different clinical parameters were then selected and mounted on microRNA array cards that served for the quantification of exosomal miRNAs in 435 BC patients before therapy and 20 healthy women. Confocal microscopy, Western blot, and ELISA were used for exosome characterization.
Results: Quantification of 45 exosomal miRNAs showed that compared with healthy women, 10 miRNAs in the entire cohort of BC patients, 13 in the subgroup of 211 HER2-positive BC, and 17 in the subgroup of 224 TNBC were significantly deregulated. Plasma levels of 18 exosomal miRNAs differed between HER2-positive and TNBC subtypes, and 9 miRNAs of them also differed from healthy women. Exosomal miRNAs were significantly associated with the clinicopathological and risk factors. In uni- and multivariate models, miR-155 (p = 0.002, p = 0.003, respectively) and miR-301 (p = 0.002, p = 0.001, respectively) best predicted pathological complete response (pCR).
Conclusion: Our findings show a network of deregulated exosomal miRNAs with specific expression patterns in exosomes of HER2-positive and TNBC patients that are also associated with clinicopathological parameters and pCR within each BC subtype.
EUSOBI and 30 national breast radiology bodies support mammography for population-based screening, demonstrated to reduce breast cancer (BC) mortality and treatment impact. According to the International Agency for Research on Cancer, the reduction in mortality is 40 % for women aged 50–69 years taking up the invitation while the probability of false-positive needle biopsy is <1 % per round and overdiagnosis is only 1–10 % for a 20-year screening. Mortality reduction was also observed for the age groups 40–49 years and 70–74 years, although with “limited evidence”. Thus, we firstly recommend biennial screening mammography for average-risk women aged 50–69 years; extension up to 73 or 75 years, biennially, is a second priority, from 40–45 to 49 years, annually, a third priority. Screening with thermography or other optical tools as alternatives to mammography is discouraged. Preference should be given to population screening programmes on a territorial basis, with double reading. Adoption of digital mammography (not film-screen or phosphor-plate computer radiography) is a priority, which also improves sensitivity in dense breasts. Radiologists qualified as screening readers should be involved in programmes. Digital breast tomosynthesis is also set to become “routine mammography” in the screening setting in the next future. Dedicated pathways for high-risk women offering breast MRI according to national or international guidelines and recommendations are encouraged.
Background: Up to 80% of breast cancer patients suffer from Cancer Related Cognitive Impairments (CRCI). Exercise is suggested as a potential supportive care option to reduce cognitive decline in cancer patients. This study will investigate the effects of a high-intensity interval endurance training (HIIT) on CRCI in breast cancer patients. Potentially underlying immunological and neurobiological mechanisms, as well as effects on patients’ self-perceived cognitive functioning and common cancer related side-effects, will be explored.
Methods: A single-blinded randomized controlled trial will be carried out. The impact of HIIT on CRCI will be compared to that of a placebo-intervention (supervised myofascial release training). Both interventions will be conducted simultaneously with the patients’ first-line chemotherapy treatment typically lasting 12–18 weeks. Fifty-nine women with breast cancer will be included in each of the two groups. The study is powered to detect (α = .05, β = .2) a medium effect size difference between the two groups (d = .5) in terms of patients’ change in cognitive testing performances, from baseline until the end of the exercise-intervention. The cognitive test battery, recommended by the International Cancer and Cognition Task Force to assess CRCI, will be used as primary measure. This includes the Hopkins Verbal Learning Test (learning/verbal memory), the Controlled Oral Word Association Test (verbal fluency) and the Trail-Making-Test A/B (attention/set-switching). The following endpoints will be assessed as secondary measures: Go-/No-Go test performance (response inhibition), self-perceived cognitive functioning, serum levels of pro- and antiinflammatory markers (tumor necrosis factor alpha, Interleukin-6, Interleukin-1 alpha, Interleukin-1 beta, C-reactive protein, Interleukin-1 receptor antagonist and Interleukin-10), serum levels of neurotrophic and growth factors (brain-derived neurotrophic factor, insulin-like growth factor 1 and vascular endothelial growth factor), as well as common cancer-related side effects (decrease in physical capacity, fatigue, anxiety and depression, sleep disturbances, quality of life and chemotherapy compliance).
Discussion: This study will provide data on the question whether HIIT is an effective supportive therapy that alleviates CRCI in breast cancer patients. Moreover, the present study will help shed light on the underlying mechanisms of potential CRCI improving effects of exercise in breast cancer patients.
Trial registration: DRKS.de, German Clinical Trials Register (DRKS), ID: DRKS00011390, Registered on 17 January 2018.
The relationship between achievement of a pathologic complete response (pCR) and favorable long-term outcome varies among breast cancer subtypes. We aimed to highlight which neoadjuvant treatment strategy could be most successful in each breast cancer subtype. A recent FDA meta-analysis on randomized neoadjuvant breast cancer trials suggests that the survival differences of patients with or without a pCR were less pronounced in luminal A-like tumors, despite the overall favorable prognosis of these patients. Moreover, even though the strong prognostic effect of pCR in HER2 positive and TNBC, the NOAH study was the only trial which showed a trend in surrogacy of pCR for long-term outcome in HER2-positive subtype. Results from GeparTrio study suggest that patients with hormone-positive tumors might need a response-guided approach, with either an intensification of treatment in case of an early response or a change to other chemotherapy in case of no early response. Furthermore, data from German neoadjuvant trials confirm that an increasing number of chemotherapy cycles is associated with a higher pCR rate, especially in patients with HER2-positive/hormone-positive tumors. In line with these suggestions, Tryphaena study showed a pCR rate that exceeding the 60% threshold, the highest pCR results presented in a large multicenter study. In TNBC, the highest pCR rate in the German neoadjuvant studies was obtained with the simultaneous application of docetaxel, doxorubicin and cyclophosphamide for 6 cycles. However, as shown in GaparQuinto and NSABP 40 trials, treatment effect in TNBC might be further maximized by adding bevacizumab, and two randomized neoadjuvant trials are expected this year to report data on the efficacy of carboplatin.