[Retracted] Resistance to the mTOR inhibitor everolimus is reversed by the downregulation of survivin in breast cancer cells.

[This retracts the article DOI: 10.3892/ol.2017.6597.].

Growth arrest and apoptosis induced by kinesin Eg5 inhibitor K858 and by its 1,3,4-thiadiazoline analogue in tumor cells.

Tumors are complex and heterogeneous but, despite this, they share the ability to proliferate continuously, irrespective of the presence of growth signals, leading to a higher fraction of actively growing and dividing cells compared with normal tissues. For this reason, the cytotoxic antimitotic treatments remain an important clinical tool for tumors. Among these drugs, antitubulin compounds constitute one of the most effective anticancer chemotherapies; however, they cause dose-limiting side effects. Therefore, it is still necessary to develop compounds with new targets and new mechanisms of action to reduce side effects or chemoresistance. Mitosis-specific kinesin Eg5 can represent an attractive target for discovering such new anticancer agents because its role is fundamental in mitotic progression. Therefore, we analyzed the effects induced by an inhibitor of kinesin Eg5, K858, and by its 1,3,4-thiadiazoline analogue on human melanoma and prostate cancer cell lines. We found that both compounds have an antiproliferative effect, induce apoptosis, and can determine a downmodulation of survivin.

Resistance to the mTOR inhibitor everolimus is reversed by the downregulation of survivin in breast cancer cells.

Everolimus (RAD001) is an inhibitor of mammalian target of rapamycin used in combination with exemestane to treat hormone receptor-positive advanced breast cancer. However, not all patients are equally sensitive to RAD001 and certain patients develop resistance. Therefore, the present study analyzed the mechanisms involved in the resistance of breast cancer cells to RAD001 in order to identify a potential tool to overcome it. The effects of RAD001 on the inhibition of cell viability, on the induction of apoptosis and autophagy and on the regulation of survivin, an anti-apoptotic protein, were evaluated in two breast cancer cell lines: BT474 (luminal B) and MCF7 (luminal A). RAD001 was demonstrated to induce autophagy in the two cell lines at following a short period of treatment (4 h) and to induce apoptosis exclusively in BT474 cells following longer periods of treatment (48 h). RAD001 induced the downregulation of survivin in BT474 cells and its upregulation in MCF7 cells. Consequently, inhibiting survivin with YM155 resulted in the acquired resistance of MCF7 cells to RAD001 being reverted, restoring RAD001-induced apoptosis. These data demonstrated that RAD001 exerted anti-proliferative and pro-apoptotic effects on breast cancer cells, but that these effects were repressed by the simultaneous up-regulation of survivin. Finally, the results demonstrated that inhibiting the expression of survivin resulted in the restoration of the anti-neoplastic activity of RAD001.

Circulating neuregulin-1 and galectin-3 can be prognostic markers in breast cancer.

BACKGROUND: It is important to identify novel plasmatic biomarkers that can contribute to assessing the prognosis and outcome of breast cancer patients. Neuregulin-1 (NRG1) and galectin-3 (Gal-3) are proteins that are involved in breast cancer development and patient survival; therefore, we studied whether the serum concentration of these 2 proteins can be correlated to breast cancer progression. METHODS: Plasmatic NRG1 and Gal-3 were evaluated in 25 healthy controls and 50 breast cancer patients at baseline and at 3 and 6 months after treatment with anthracyclines and taxanes, with or without trastuzumab. RESULTS: NRG1 and Gal-3 were significantly more elevated in cancer patients than in healthy controls; furthermore, NRG1 and Gal-3 were significantly increased after chemotherapy and were predictive of mortality at 1 year. CONCLUSIONS: Circulating NRG1 and Gal-3 can be additional biomarkers indicative of prognosis and outcomes for breast cancer patients.

Anthracycline-Free Neoadjuvant Chemotherapy Ensures Higher Rates of Pathologic Complete Response in Breast Cancer.

PURPOSE: Neoadjuvant chemotherapy (NCT) is a standard of care for locally advanced and initially inoperable breast cancer. NCT can test chemotherapy efficacy and can be followed by breast-conserving surgery. Considering taxanes as one of the most effective agents, we analyzed the efficacy of a neoadjuvant schedule without anthracyclines and based only on taxanes and carboplatin, trying to avoid cardiotoxicity, which is the most serious side effect correlated with anthracyclines. PATIENTS AND METHODS: We enrolled 61 patients with breast cancer, belonging to 4 subgroups, according to molecular phenotypes: 24 triple-negative/basal-like, 13 HER2-like, 20 luminal B, and 4 luminal A. All patients underwent weekly chemotherapy with carboplatin AUC2, paclitaxel 80 mg/m2, with trastuzumab (in case of HER2 positivity) 2 mg/kg, except for luminal A patients, who underwent only hormonal therapy. Among 61 patients, 26 (43%) received modified radical mastectomy and 35 (57%) received breast-conserving surgery. RESULTS: The patients obtaining pathologic complete response (pCR) were 20 (83%) of 24 triple-negative/basal-like, 10 (76%) of 13 HER2-like, 6 (30%) of 20 luminal B, and 3 (75%) of 4 luminal A. All the patients were evaluated for toxicity: no grade 4 was detected, 5 patients experienced grade 3 neuropathy, then reverted to G2 after chemotherapy discontinuation. At a minimum follow-up of 5 years, median overall survival was 48 months. CONCLUSION: Taxane/carboplatin-based/anthracycline-free NCT is the best treatment for inoperable breast cancer in terms of efficacy and toxicity, because this approach avoids cardiotoxicity and obtains an optimal rate (64%) of pCR, with an important impact on survival.

Cardiotoxicity of Aromatase Inhibitors in Breast Cancer Patients.

Aromatase inhibitors represent an effective endocrine treatment for patients with hormone receptor-positive breast cancer, in early stage and in metastatic disease. However, by decreasing levels of serum estrogens they also potentially reduce the protective effect of estrogens on the cardiovascular system. Patients treated with aromatase inhibitors, in fact, compared with those who receive tamoxifen, more often develop hyperlipidemia, hypercholesterolemia, and hypertension, which are recognized risk factors for cardiovascular disease. This might raise some concerns especially in the adjuvant setting where the aim of treatment is the cure, and for postmenopausal patients who are already at risk for cardiovascular disease. However, whether the relative higher incidence of cardiac adverse events reported with aromatase inhibitors compared with tamoxifen is related to an actual cardiac toxicity of aromatase inhibitors rather than a cardioprotective effect of tamoxifen is still unclear. In this article we review the available literature on cardiotoxicity of aromatase inhibitors and provide some practical advice to improve the cardiovascular safety profile of these drugs.

Long-Lasting Stent Placement in an Elderly Advanced Ovarian Cancer Patient.

BACKGROUND: Ovarian cancer is usually diagnosed at an advanced stage, most often co-occurring with malignant bowel obstruction. Affected patients are generally in poor physical condition, and it is important to manage the bowel obstruction to improve quality of life. CASE REPORT: We present the case of a 75-year-old woman who underwent a left hemicolectomy for an ovarian carcinoma with bowel obstruction. 3 years after hemicolectomy, the patient presented with an extrinsic anastomotic substenosis. A self-expanding metal stent was placed which remained in place for 7 years, rendering other invasive surgical treatments unnecessary. CONCLUSION: The placement of a long-lasting stent is an important option in patients with bowel obstruction subsequent to recurrent ovarian cancer, since this provides a viable alternative to surgery and increases patients' quality of life.

The kinesin Eg5 inhibitor K858 induces apoptosis but also survivin-related chemoresistance in breast cancer cells.

Inhibitors of kinesin spindle protein Eg5 are characterized by pronounced antitumor activity. Our group has recently synthesized and screened a library of 1,3,4-thiadiazoline analogues with the pharmacophoric structure of K858, an Eg5 inhibitor. We herein report the effects of K858 on four different breast cancer cell lines: MCF7 (luminal A), BT474 (luminal B), SKBR3 (HER2 like) and MDA-MB231 (basal like). We demonstrated that K858 displayed anti-proliferative activity on every analyzed breast cancer cell line by inducing apoptosis. However, at the same time, we showed that K858 up-regulated survivin, an anti-apoptotic molecule. We then performed a negative regulation of survivin expression, with the utilization of wortmannin, an AKT inhibitor, and obtained a significant increase of K858-dependent apoptosis. These data demonstrate that K858 is a potent inhibitor of replication and induces apoptosis in breast tumor cells, independently from the tumor phenotype. This anti-proliferative response of tumor cells to K858 can be limited by the contemporaneous over-expression of survivin; consequently, the reduction of survivin levels, obtained with AKT inhibitors, can sensitize tumor cells to K858-induced apoptosis.

Breast cancer cells respond differently to docetaxel depending on their phenotype and on survivin upregulation.

Breast cancer is characterized by molecular heterogeneity, and four major breast cancer subtypes have been identified, each characterized by significant differences in survival, prognosis, and response to therapy. We have studied the effects of docetaxel treatment on apoptosis and survivin expression in four breast cancer cell lines: MCF7 (luminal A: estrogen receptor-positive and progesterone receptor-positive, ErbB2-negative), BT474 (luminal B: estrogen receptor/progesterone receptor/ErbB2-positive), SKBR3 (HER2-like: estrogen receptor/progesterone receptor-negative, ErbB2-positive), and MDA-MB231 (basal-like: estrogen receptor/progesterone receptor/ErbB2-negative). We demonstrated that docetaxel-induced apoptosis and survivin upregulation (MCF7 p = 0.002, BT474 p = 0.001, SKBR3 p = 0.001) in luminal A/B and HER2-like cells, while it induced mainly necrosis and a lower rate of survivin upregulation (MDA-MB231 p = 0.035) in basal-like cells. Wortmannin, a p-Akt inhibitor, was able to revert surviving upregulation and, at the same time, induced an increase of docetaxel-dependent apoptosis, suggesting that reduced levels of survivin can sensitize tumor cells to apoptosis. These data show that the analyzed breast cancer cell lines respond differently to docetaxel, depending on their receptor expression profile and molecular phenotype. Yet, these data confirm that one of the pathways involved in taxane-related chemoresistance is the upregulation of survivin. Further studies on the molecular mechanisms of chemoresistance and on the different modalities of apoptosis induced by chemotherapeutic agents are requested to better understand how cancer cells evade cell death, in order to design new kind of anticancer agents and survivin could represent a future target for this kind of research.

Serum biomarkers evaluation to predict chemotherapy-induced cardiotoxicity in breast cancer patients.

Anti-neoplastic chemotherapy can determine various side effects, including cardiotoxicity, and no real guidelines for its early detection and management have been developed. The aim of this study is to find some plasmatic markers able to identify breast cancer patients that are at greater risk of developing cardiovascular complications during chemotherapy, in particular heart failure. A prospective study on 100 breast cancer patients with mean age of 66 years in adjuvant treatment with anthracyclines, taxanes, and trastuzumab was performed. Patients underwent cardiological examination before starting treatment (T0) and at 3 months (T1), 6 months (T2), and 1 year (T3) after treatment. Evaluation of serum cardiac markers and N-terminal pro-brain natriuretic peptide (NT-proBNP) was performed at T0, T1, T2, and T3, simultaneously to electrocardiogram and echocardiogram, showing a significant increase in NT-proBNP concentration (p > 0.0001) at T1, T2, and T3, before left ventricular ejection fraction decrease became evident. Human epidermal growth factor receptor 2 (HER2)-negative patients were more susceptible to mild hematological cardiotoxicity, while HER2-positive patients were more susceptible to severe cardiotoxicity. A significant correlation between NT-proBNP increased values after chemotherapy and prediction of mortality at 1 year was evidenced. From our experience, serum biomarker detection was able to support an early diagnosis of cardiac damage, also in the absence of left ventricular ejection fraction decrease. Therefore, the evaluation of specific plasmatic markers for cardiac damage is more sensitive than echocardiography in the early diagnosis of chemotherapy-related cardiotoxicity; furthermore, it can also add a prognostic value on outcome.

Are pharmacogenomic biomarkers an effective tool to predict taxane toxicity and outcome in breast cancer patients? Literature review.

PURPOSE: Breast cancer is a heterogeneous disease, characterized by various molecular phenotypes that correlate with different prognosis and response to treatments. Taxanes are some of the most active chemotherapeutic agents for breast cancer; however, their utilization is limited, due to hematologic and cumulative neurotoxicity on treated patients. To understand why only some patients experience severe adverse effects and why patients respond and develop resistance with different rates to taxane therapy, the metabolic pathways of these drugs should be completely unraveled. The variant forms of several genes, related to taxane pharmacokinetics, can be indicative markers of clinical parameters, such as toxicity or outcome. METHODS: The search of the data has been conducted through PubMed database, presenting clinical data, clinical trials and basic research restricted to English language until June 2015. RESULTS: We studied the literature in order to find any possible association between the major pharmacogenomic variants and specific taxane-related toxicity and patient outcome. We found that the data of these studies are sometimes discordant, due to both the small number of enrolled patients and the heterogeneity of the examined population. CONCLUSIONS: Among all analyzed genes, only CYP1B1 and ABCB1 resulted the strongest candidates to become biomarkers of clinical response to taxane therapy in breast cancer, although their utilization still remains an experimental procedure. In the future, greater studies on genetic polymorphisms should be performed in order to identify differentiating signatures for patients with higher toxicity and with resistant or responsive outcome, before the administration of taxanes.

Taxane induced neuropathy in patients affected by breast cancer: Literature review.

Taxane induced neuropathy (TIN) is the most limiting side effect of taxane based chemotherapy, relative to the majority of breast cancer patients undergoing therapy with both docetaxel and paclitaxel. The symptoms begin symmetrically from the toes, because the tips of the longest nerves are affected for first. The patients report sensory symptoms such as paresthesia, dysesthesia, numbness, electric shock-like sensation, motor impairment and neuropathic pain. There is a great inter-individual variability among breast cancer women treated with taxanes, in fact 20-30% of them don't develop neurotoxicity. Actually, there is no standard therapy for TIN, although many medications, antioxidants and natural substances have been tested in vitro and in vivo. We will summarize all most recent literature data on TIN prevention and treatment, in order to reach an improvement in TIN management. Further studies are needed to evaluate new therapies that restore neuronal function and improve life quality of patients.

On and off metronomic oral vinorelbine in elderly women with advanced breast cancer.

BACKGROUND: Elderly patients with metastatic breast cancer (MBC) have more problems receiving chemotherapy than younger patients, especially with the presence of multiple comorbidities, adverse drug events and functional decline. Low-dose oral administration of cytotoxic agents such as vinorelbine, a semisynthetic vinca alkaloid that interferes with microtubule assembly, leading to arrest of cell division, is usually effective and well tolerated. METHODS: From February 2010 to February 2014, 32 patients with MBC, median age 76 years (range 69-83) were treated with oral vinorelbine 30 mg (total dose), one day on and one day off, until disease progression or unacceptable toxicity levels were reported. Toxicity, quality of life and clinical benefit were evaluated. Matched t-tests were conducted to discern whether quality-of-life indicator (p<0.05 was considered significant) differed before and 6 months after treatment. Statistical analysis was performed using Graph Pad Prism 5.0 (GraphPad Software Inc., San Diego, CA, USA). RESULTS: No grade 3 and 4 adverse events were reported. A clinical benefit of 50% was found in our cohort. On and off metronomic vinorelbine oral administration resulted in good tolerability and safe profile in our selected elderly population, and improved patient adherence to therapy. CONCLUSIONS: The present study demonstrated that metronomic vinorelbine might be a potential treatment in elderly patients by reducing adverse effects and increasing quality of life, setting the stage for future extensive clinical trials.

Chemotherapy of rare skin adnexal tumors: a review of literature.

Malignant skin adnexal tumors are rare neoplasms which are derived from adnexal epithelial structures of the skin: hair follicle, or sebaceous, apocrine or eccrine glands. Among them, eccrine porocarcinoma is the most frequent, with an aggressive behavior compared to other more common forms of non-melanoma skin cancer. Only few reports describe the treatment of metastatic adnexal tumors, and there is no consensus about the better strategy of chemotherapy. Given the few cases and the absence of randomized clinical trials, it is important to collect clinical experiences on these tumors. Most of these adenocarcinomas are very aggressive and also chemoresistant, and only a targeted-therapy could have an impact on patient survival. Therefore, further studies on the biology of these diseases are necessary. The purpose of the present review is to discuss the treatment of malignant neoplasms of cutaneous adnexae and to suggest some future therapeutic options based on targeted-therapy.

Elderly woman with triple-negative metastatic breast cancer successfully treated with metronomic capecitabine.

Triple-negative breast cancer phenotype (estrogen receptor-, progesterone receptor- and human epidermal growth receptor 2-negative) is one of the most aggressive molecular subtypes, accounting for 15-20% of all breast tumors. There is no standard treatment for this setting of patients except anthracyclines and taxanes, but not all elderly patients can tolerate these kinds of agents. We describe the case of an elderly woman affected by triple-negative breast cancer with bone and brain metastases who has been treated for five years with metronomic capecitabine. At the moment, the patient has stable disease and enjoys good quality of life. She had initially been diagnosed with a poor Karnofsky index, which has actually improved from 50 to 90. Metronomic capecitabine treatment has clearly improved her quality of life, as documented by the results of the Functional Assessment of Cancer Therapy Breast.

Adhesion to type V collagen enhances staurosporine-induced apoptosis of adrenocortical cancer cells.

Adrenocortical carcinoma (ACC) is a rare and aggressive tumor characterized by poor prognosis and resistance to conventional chemotherapy. Many chemotherapy agents act determining apoptosis, therefore, studying the responsiveness of ACC to apoptosis inducing molecules, can help to identify possible conditions to promote cancer cell death. Tumor progression is strictly related to the interaction between cancer cells and stroma; yet, extracellular matrix remodeling regulates tumor cell proliferation and apoptosis. At this purpose, we have studied staurosporine-induced apoptosis of ACC cell line H295R adherent to different extracellular matrix molecules. H295R cells grown on plastic showed a low responsiveness to staurosporine, with an apoptotic rate of 24 %, as compared to breast cancer MCF7 cells, with an apoptotic rate of 60 %. The adhesion of H295R cells to type V collagen induced a significant increase of apoptosis up to 52 %; this effect was inhibited by anti-integrin alpha2 antibody. At the same time, the adhesion of H295R cells on polylysine, matrigel, lamimin, fibronectin, and type I-III collagens didn't modify staurosporine-induced apoptosis. Staurosporine-treated H295R cells showed an increase of PARP cleavage and of annexin-V expression, when adherent to type V collagen. Yet, staurosporine induced Akt and Erk activation on H295R cells: the adhesion on type V collagen didn't modify Akt activation, while determined a dramatic inhibition of Erk activation. The described data demonstrate that the adhesion to type V collagen specifically increases the responsiveness of ACC cells to staurosporine-induced apoptosis and that this is probably obtained through the inhibition of Erk activation.

Prevention of osteonecrosis of the jaw in patients with bone metastases treated with bisphosphonates.

Bisphosphonates (BPs) are potent inhibitors of osteoclast-mediated bone resorption and are widely used in the treatment of bone metastases. Osteonecrosis of the jaw (ONJ) is the worst side-effect related to BP use. At our Center, we have implemented internal guidelines regarding the management of patients with bone metastases from solid tumors. Our analysis includes 200 patients affected by solid tumors with bone metastases who received zoledronic acid. They underwent a baseline mouth assessment to evaluate their dental conditions and to perform dental care; a dental follow-up was performed every six months. All patients received calcium and vitamin D daily. Dental examination and application of preventive measures led to a total reduction in ONJ in our patients treated with zoledronic acid. The keystone in management of ONJ is prevention, and the risk of developing ONJ during treatment with zoledronic acid is reduced by implementing preventive measures.