Metastatic BCa Research Articles

Metastatic Tropism in Urothelial Carcinoma With Variant Histology: A Comprehensive NCDB Analysis

IntroductionBladder cancer (BCa) with variant histology (VH) is notably aggressive and not as well studied as pure urothelial carcinoma (UC). The characteristics of variant BCa in the setting of metastatic disease may contribute to treatment response/resistance and subsequent disease progression. In this study, we sought to assess VH's impact on metastasis sites at presentation in metastatic BCa. MethodsThe National Cancer Database was queried from 2004 to 2019 to analyze cT1-4 cN0-3 cM1 patients with UC and VH BCa. The primary endpoint was the presence of metastasis to different organs. Binomial multivariable logistic regression was performed to determine the impact of VH on metastatic sites while controlling for multiple variables. ResultsTotal 6005 eligible patients diagnosed with either UC or VH were included. Patients with small cell histology, the second most common VH, were more likely to have liver metastasis (OR: 4.335) while less likely to have lung metastases (OR: 0.521). Squamous cell carcinoma decreased the odds of bone metastasis (OR: 0.449). Adenocarcinoma increased the odds of lung metastases (OR: 1.690). Micropapillary VH is less likely to metastasize to the lungs (OR: 0.182) but more likely to spread to nonregional lymph nodes (OR: 2.623). Sarcomatoid subtype did not exhibit a statistically significant variation in the odds ratio for any of the metastatic sites. ConclusionThis study comprehensively analyzes the limited research regarding metastatic BCa and VH. Our analysis underscores each subtype exhibiting heterogeneous metastatic tropism. Importantly, these findings illustrate the role of routine somatic gene expression profiling to guide adequate staging and treatment intensification and to offer a foundation for future studies of VH BCa care.

Androgen Receptor in Hormone Receptor-Positive Breast Cancer.

Breast cancer subtypes expressing hormone receptors (HR+ BCa) have a good prognosis and respond to first-line endocrine therapy (ET). However, the majority of HR+ BCa patients exhibit intrinsic or acquired ET resistance (ET-R) and rapid onset of incurable metastatic BCa. With the failure of conventional ET, limited targeted therapy exists for ET-R HR+ BCa patients. The androgen receptor (AR) in HR-negative BCa subtypes is emerging as an attractive alternative target for therapy. The AR drives Luminal AR (LAR) triple-negative breast cancer progression, and LAR patients consistently exhibit positive clinical benefits with AR antagonists in clinical trials. In contrast, the function of the AR in HR+ BCa is more conflicting. AR in HR+ BCa correlates with a favorable prognosis, and yet, the AR supports the development of ET-R BCa. While AR antagonists were ineffective, ongoing clinical trials with a selective AR modulator have shown promise for HR+ BCa patients. To understand the incongruent actions of ARs in HR+ BCa, the current review discusses how the structure and post-translational modification impact AR function. Additionally, completed and ongoing clinical trials with FDA-approved AR-targeting agents for BCa are presented. Finally, we identify promising investigational small molecules and chimera drugs for future HR+ BCa therapy.

Abstract 5675: Pathological crosstalk between osteocytes and breast cancer cells in bone metastasis

Abstract Bone provides an ideal niche for breast cancer cells (BCa) to reside and proliferate and is a frequent site of BCa metastasis. Osteocytes are the most abundant skeletal cells and permanent residents of bone. However, the role of osteocytes in BCa bone metastasis remains understudied. Here, we investigated the crosstalk between metastatic BCa cells and osteocytes. In vitro cultures revealed that conditioned media (CM) derived from metastatic E0771 BCa cells decreased by 50% the number of alive MLO-A5 and MLO-Y4 osteocyte-like cell lines. BCa cells modestly increased osteocyte apoptosis (2% vs. 6%, alone vs. exposed to BCa, respectively). Treatment with DEVD, a caspase 3 inhibitor, blocked osteocyte apoptosis but did not prevent the decrease in osteocytes induced by BCa. Thus, we studied osteocyte senescence, a process that causes irreversible cell cycle arrest and profound changes in gene expression. We found that BCa-CM upregulated the expression of markers of senescence markers (p16, p21) and senescence-associated secretory phenotype (Mmp13, Mmp9, Vcam-1) in osteocyte-like cell lines. Similarly, BCa-CM increased the expression of senescent markers in ex vivo bone organ cultures containing primary osteocytes. Osteocytes increased BCa cell proliferation by increasing cyclin D1 expression Through both cell-to-cell interactions and secretion of soluble factors., osteocytes increased BCa cell proliferation by increasing cyclin D1 expression. Moreover, osteocyte-derived CM stimulated BCa cells migration and invasion capabilities and upregulated the expression of genes involved in migration (Vcam-1 and N-cadherin). Co-culture with stromal cells also stimulated BCa cell proliferation, invasion, and migration. However, the increases induced by stromal cells were four-fold lower than those seen with osteocytes. Overall, our results suggest that BCa cells reprogram osteocytes, which acquire a senescent phenotype, whereas osteocytes produce factors that stimulate tumor growth, migration, and invasion. Together, these findings support the existence of a crosstalk between osteocytes and BCa cells in the metastatic niche that favors the progression of breast cancer in bone. Future studies are warranted to examine the contribution of osteocyte senescence and osteocytes-derived factors in animal models of breast cancer metastasis. Citation Format: Manish Adhikari, Hayley Sabol, Aric anloague, Sharmin Khan, Jesus Delgado-Calle. Pathological crosstalk between osteocytes and breast cancer cells in bone metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5675.

Osteopontin level and promoter polymorphism in patients with metastatic breast cancer.

Cancer initiation typically occurs when a proto-oncogene's coding region undergoes mutation, resulting in uncontrollable cell growth and division, or when a tumour suppressor gene's coding region is affected by a mutation that inhibits activity of the resulting gene product. The pathophysiologic result is, respectively, exaggerated cell-cycle growth or deficient programmed cell death. Osteopontin (opn) is an integrin-binding phosphoprotein that is expressed on the surface of normal cells. Osteopontin has a major role in diverse tumour components, especially those implicated in invasion and metastasis. In the present study, we aimed to illustrate the value of opn as a possible contributor in breast cancer (bca). This prospective study included 115 patients newly diagnosed with bca and distant metastasis who were recruited from the Oncology Center, Mansoura University, and the Department of Clinical Oncology and Nuclear Medicine, Mansoura University Hospital, Egypt. The patients recruited had been diagnosed with disseminated visceral metastasis (visceral crisis), with or without bone metastasis; patients with cranial metastasis were excluded from the study. All patients received first-line chemotherapy with docetaxel 75 mg/m2 plus cisplatin 75 mg/m2 or carboplatin 6 auc (area under the curve) on day 1 every 21 days for a maximum of 6 cycles or till development of toxicity. Trastuzumab (in cases of her2-positive disease) was given whenever possible (if government assistance or personal finances permitted). Serum levels of opn were assessed by enzyme-linked immunosorbent assay (elisa) before treatment was started. A group of 30 matched healthy women whose median serum opn level was 15 ng/dL were included, and that level was therefore defined as the cut-off value. In addition, opn gene mutation was determined by polymerase chain reaction (pcr). Correlations of pretreatment serum opn and opn gene mutation with various patient clinicopathologic variables, response to the treatment, progression-free survival (pfs), and overall survival (os) were assessed. Mean serum opn was highest in her2-amplified bca (64.4 ± 42.3 ng/dL), and then in triple-negative bca (55.9 ± 34.7 ng/dL), followed by the luminal B and A subtypes (38.4 ± 33.1 ng/dL and 36.3 ± 32.2 ng/dL respectively, p = 0.017). Testing by pcr revealed that opn gene mutation was highest in triple-negative bca (85% opn mutant vs. 15% non-mutant), and then in her2-overexpressed bca (80% opn mutant vs. 20% non-mutant), followed by luminal B bca (61.9% opn mutant vs. 38.1% non-mutant); the least expression was detected in luminal A bca (57.9% opn mutant vs. 42.1% non-mutant). Interestingly, patients with high serum opn and opn gene mutation experienced both poor pfs (median: 12 months vs. 14 months; p = 0.001) and poor os (median: 14 months vs. 18 months; p = 0.001). Moreover, participants with opn gene mutation experienced a poor response: of those with progressive disease, 74% had opn mutation and 26% had unmutated opn (p = 0.04). Additionally, high pretreatment serum opn was correlated with poor treatment response: 49.1 ± 33.8 ng/dL in patients with progressive disease and 35.5 ± 34.3 ng/dL in those who achieved a complete response, a partial response, or stable disease (p = 0.05). Strong concordance was found between high serum opn and opn gene mutation in 69 tumours (79.3%), and strong concordance was detected between normal or low serum opn and non-mutant opn in 28 tumours (60.8%). The current prospective work helps to highlight opn as a valid prognostic biomarker for patients with metastatic bca and reveals that high pretreatment serum opn and opn gene mutation are both strongly linked with poor response and survival. Concordance between elisa and pcr results indicates that either method can be used for the evaluation of opn. Increased opn gene mutation in triple-negative bca could assist in tailoring the treatment response in this very aggressive tumour subtype and could be considered a targetable molecule in future studies.

A population-based analysis of breast cancer incidence and survival by subtype in Ontario women.

Breast cancer (bca) is the type of cancer most frequently diagnosed among women in Canada. Breast cancer is categorized into various molecular subtypes by the expression of estrogen receptor (er), progesterone receptor (pgr), and her2 (human epidermal growth factor receptor 2). Currently, Canada has no national cancer registry with epidemiology data by subtype. Thus, we conducted a study to determine incidence, survival, and clinicopathologic characteristics by bca subtype [triple negative breast cancer (tnbc); her2+; and hormone receptor-positive (hr+), her2-] in Canadian women newly diagnosed with bca. Female patients diagnosed between 1 April 2012 and 31 March 2016 (fiscal 2012-2015) were identified in the Ontario Cancer Registry, and individual patient data were linked to data in provincial health administrative databases. Descriptive statistics and Kaplan-Meier curves were generated. In this cohort, 3277 women (9.5%) had tnbc, 4902 (14.3%) had her2+ bca, and 22,247 (64.8%) had hr+, her2-breast cancer. The annual incidence was 15 per 100,000 for the tnbc group, 21-23 per 100,000 for the her2+ group, and 97-105 per 100,000 for the hr+, her2- group. The lowest median overall survival (mos) of 8.9 months was observed in women with clinical stage iv tnbc. In comparison, the mos was 37.3 months in those with her2+ disease and 35.2 months in those with and hr+, her2- metastatic bca. In the present study, the most recent and largest administrative database analysis of a Canadian population to date, we observed a subtype distribution consistent with previously reported data, together with comparable annual incidence and overall survival patterns.

Prognosis in young women less than 40 years of age with brain metastasis from breast cancer.

Brain metastasis from breast cancer (bca) in young women is doubly devastating because both quality of life and life expectancy are significantly reduced. With new radiation technology and drugs that have emerged, survival is expected to increase for these young women. Using the oacis and sardo patient databases, we identified 121 patients diagnosed with bca and brain metastasis between 2006 and 2016 at the University of Montreal Hospital Centre. Those patients were divided into Group A, patients who developed brain metastasis during the evolution of metastatic bca, and Group B, patients whose first metastasis was to the brain. For each group, we compared young patients (<40 years of age) with older patients (≥40 years of age). Among the 121 patients with brain metastasis, median overall survival (mos) was significantly longer for those less than 40 years of age than for those 40 or more years of age (18 months vs. 4 months, p < 0.001). With respect to the timing of brain metastasis, survival was significantly longer in Group B than in Group A (7 months vs. 4 months, p = 0.032). In Group A, mos was significantly longer for patients less than 40 years of age than for patients 40 or more years of age (18 months vs. 3 months, p = 0.0089). In Group B, the 2-year overall survival rate was 57% for patients less than 40 years of age and 12% for those 40 or more years of age (mos: not reached vs. 7 months; p = 0.259). In our single-centre retrospective cohort of women with brain metastasis from bca, prognosis was better for young women (<40 years) than for older women (≥40 years). Survival was also longer for patients whose initial metastasis was to the brain than for patients whose brain metastasis developed later in the disease course. In patients who received systemic treatment, median survival remained significantly higher in women less than 40 years of age. Further studies are needed to validate those results.

Abstract 2685: Targeting TGFβ signaling pathways in bone metastatic breast cancer cells to limit metastatic progression using curcuminoids, a turmeric-derived natural product

Abstract Tumor-cell TGFβ signaling has been demonstrated to drive osteolytic breast cancer bone metastases (BrCa BMET) in mouse models. This established an important link between the microenvironment and tumor cells in bone, wherein osteoclast-mediated bone resorption stimulates the release of TGFβ from bone matrix, which induces tumoral secretion of osteolytic factors, such as parathyroid-related protein (PTHrP) that drive further osteoclast-mediated bone destruction in a positive feedback loop. These findings have prompted interest in the use of pharmacologic TGFβ inhibitors, currently under development, for the treatment of BrCa BMET. Interestingly, studies have demonstrated antagonistic effects of a natural product, turmeric-derived polyphenols called curcuminoids (CURC), on BrCa BMET progression and TGFβ-inducible, Smad-dependent signaling in a TGFβ-dependent human xenograft model (human MDA-MB-231 [MDA-SA]).The studies described here were undertaken to determine whether this inhibitory effect is generalizable to other BrCa cells that form TGFβ-dependent BMETs (human MDA-1833 and MDA-2287; murine 4T1) and to begin to elucidate the mechanism by which CURC block BrCa cell TGFβ signaling. Analogous to prior findings using MDA-SA cells forming BMET that are dependent on TGFβ-inducible tumoral secretion of PTHrP via Smad and non-Smad (specifically, p38) dependent pathways, CURC inhibited TGFβ inducible activation (phosphorylation) of receptor Smad2 (Western) in all TGFβ-dependent BrCa cell lines tested.In MDA-SA cells, CURC inhibition of TGFβ-stimulated Smad2 phosphorylation was time- and dose-dependent (Western), and associated with decreased expression of a Smad-dependent luciferase reporter gene in transiently transfected cells. In both MDA-SA and 4T1 cells, these changes were accompanied by decreased TGFβ-stimulated PTHrP secretion (RIA). These effects in MDA-SA cells were not associated with changes in the expression of canonical TGFβ signaling proteins, such as Smad anchor for receptor activation (SARA), which is involved in Smad phosphorylation, or Smad4, a required cofactor for Smad-mediated gene transcription. Also unchanged were noncanonical TGFβ-stimulated, Smad-independent signaling pathways (e.g., p38, ERK1/2 or JNK). Of note, however, in all cell lines tested, CURC inhibition of Smad2 phosphorylation was accompanied by a decrease in constitutive Smad2 levels, with variable decreases in the ratio of phosphorylated vs. total Smad levels. These results suggest that CURC can specifically and uniformly inhibit Smad-regulated TGFβ signaling in bone metastatic BCa cells forming TGFβ-dependent osteolytic lesions, an effect that may be mediated, at least in part, by changes in constitutive levels of receptor-regulated Smad expression. Citation Format: Andrew Kunihiro, Julia A. Brickey, Jen B. Frye, Janet L. Funk. Targeting TGFβ signaling pathways in bone metastatic breast cancer cells to limit metastatic progression using curcuminoids, a turmeric-derived natural product [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2685.

Abstract 4261: Pathways of metastatic bladder cancer from a longitudinal patient data set

Abstract Bladder cancer (BCa), the 6th commonest cancer in the U.S., is highly lethal when metastatic. Sites and patterns of patient-specific metastatic spread are deemed random and unpredictable. Whether BCa metastatic patterns can be quantified and predicted more accurately is unknown. We used a prospective, longitudinal dataset of 3,505 BCa patients who underwent definitive treatment following diagnosis and were continuously enrolled (1971-2016; mean follow-up 6.13 years). Metastases developed in 30% (n=1,040) of patients, with 5-year survival rate of 18%, compared to 72% in those without metastases (n=2,465). The three commonest metastatic sites at time-of-first progression were pelvis (n=283; 27.2%), bone (n=274; 26.3%), and lung (n=247; 23.8%). We illustrate metastatic pathway progression as color-coded, circular, tree-ring diagrams (primary in the center; metastatic sites outwards). Markov chain modeling, denoting nodes as potential anatomic metastatic sites, indicated higher probability of spread from the bladder to pelvis (15.6%), bone (15.6%), and lung (13.9%), categorizing 4 of 10 anatomical sites as ‘spreaders' and 2 as ‘sponges'. We created a dynamical, data-visualization, web-platform that displays temporal, spatial and Markov modeling figures with predictive capability. For contrasting subgroups, this platform indicated differences in transition probabilities, rank-ordering of metastatic sites, and spreader/sponge node classification. Spatiotemporal patterns of BCa metastasis and sites of spread indicate underlying organotropic mechanisms in the prediction of response. This recognition opens the possibility of organ site-specific therapeutic targeting in the oligo-metastatic disease setting. In the precision medicine era, visualization of complex, time-resolved clinical data will enhance management of post-operative, metastatic BCa patients. Citation Format: Jeremy M. Mason, Zaki Hasnain, Gus Miranda, Karanvir Gill, Paul K. Newton, Inderbir S. Gill, Peter Kuhn. Pathways of metastatic bladder cancer from a longitudinal patient data set [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4261.

Role of Radical Cystectomy in Non-Organ Confined Bladder Cancer: A Systematic Review.

Background:Currently, a diagnosis of non-organ confined bladder cancer (NOCBCa) confers a grave prognosis. The mainstay of treatment consists of systemic chemotherapy. However, it must be recognized that NOCBCa is a heterogeneous disease state with important clinical distinctions. While surgical extirpation has traditionally been regarded as overly aggressive for all NOCBCa patients, its utility as part of a multimodal treatment strategy in various clinical scenarios has not been thoroughly investigated.Objective:To perform a review of the literature regarding the role of radical cystectomy and pelvic lymph node dissection (RC-LND) in the setting of NOCBCa.Methods:Medline, and Pubmed electronic database were queried for English language articles from January 1990 to Nov 2016 on RC-LND for cT4, lymph node positive, and metastatic urothelial cancer. NOCBCa was separated into four distinct clinical scenarios: 1. Locally advanced/unresectable disease (cT4bN0M0); 2. Occult pelvic nodal disease (pN+) (cTxN0M0 and pTxN1-3Mx); 3. Clinical node positive disease (cN+) (cTxN1-3M0); and 4. Distant metastatic disease (TxNxM1). Evidence for the role of RC-LND in each of these clinical scenarios was summarized.Results:cT4b may be more effectively treated by presurgical chemotherapy (PSC) than other forms of NOCBCa. Although clinical response predicted improved survival, surgical factors, such as surgical margin status may also play a role in determining outcomes. In well selected patients, 5-year CSS may reach 60% after consolidative RC-LND. Survival in patients found to have pathologic nodal metastases without PSC was dictated not only by the histologically verified metastatic nodal disease burden, but also by the meticulousness of the lymph node dissection. In these patients, adjuvant chemotherapy may improve survival. On the other hand, in patients undergoing RC-LND after PSC, pathologic complete response (pCR) was the strongest predictor of improved CSS. The results of population based studies have suggested a therapeutic role by consolidative RC-LND in both patients with cN+ and metastatic BCa (mBCa). For the cN+ population, 5-year OS was 31% in patients undergoing RC-LND after PSC vs. 14% in those receiving chemotherapy alone. Similarly, consolidative intensive local therapy improved OS by approximately 5 months in patients with mBCa. Metastasectomy has also been shown to be effective in small retrospective series and may especially be useful in patients with solitary pulmonary lesions.Conclusions:Extirpative treatment of the primary tumor may be an important step in the management of de novo NOCBCa. The current retrospective and population based studies have demonstrated improved survival outcomes in patients with NOCBCa following RC-LND, especially in those with favorable response to PSC. With the advent of minimally invasive surgery and the enhanced post-surgical recovery protocols, RC-LND has not only been demonstrated to be feasible, but also tolerable in the setting of advanced BCa. Well designed, prospective trials are needed to definitively assess the value of surgical extirpation for NOCBCa patients.

MP58-11 IMPACT OF INTRA- AND POST-OPERATIVE BLOOD TRANSFUSION ON THE INCIDENCE, TIMING AND PATTERN OF DISEASE RECURRENCE AFTER RADICAL CYSTECTOMY

You have accessJournal of UrologyBladder Cancer: Invasive V1 Apr 2017MP58-11 IMPACT OF INTRA- AND POST-OPERATIVE BLOOD TRANSFUSION ON THE INCIDENCE, TIMING AND PATTERN OF DISEASE RECURRENCE AFTER RADICAL CYSTECTOMY Marco Moschini, Andrea Gallina, Marco Bandini, Paolo Dell'Oglio, Giovanni La Croce, Giusy Burgio, Agostino Mattei, Rocco Damiano, Vincenzo Mirone, Alberto Briganti, Francesco Montorsi, Renzo Colombo, and Shahrokh Shariat Marco MoschiniMarco Moschini More articles by this author , Andrea GallinaAndrea Gallina More articles by this author , Marco BandiniMarco Bandini More articles by this author , Paolo Dell'OglioPaolo Dell'Oglio More articles by this author , Giovanni La CroceGiovanni La Croce More articles by this author , Giusy BurgioGiusy Burgio More articles by this author , Agostino MatteiAgostino Mattei More articles by this author , Rocco DamianoRocco Damiano More articles by this author , Vincenzo MironeVincenzo Mirone More articles by this author , Alberto BrigantiAlberto Briganti More articles by this author , Francesco MontorsiFrancesco Montorsi More articles by this author , Renzo ColomboRenzo Colombo More articles by this author , and Shahrokh ShariatShahrokh Shariat More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.1806AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Administration of blood transfusion (BT) has been associated with a decrease in survival expectancies in patients treated with radical cystectomy (RC). However, mechanisms associated to this relation are unknown. To test the postulated immunosuppressive effect mediated by BT in RC patients. Specifically, we evaluated if the usage of BT may influence risk and pattern of distant recurrences development after RC. METHODS we evaluated 1,081 contemporary patients with clinically non metastatic BCa with available follow-up and recurrence site information, treated with RC and pelvic lymph node dissection (PLND) at a single tertiary care referral center (testing cohort) between 1990 and 2013. Findings from the first dataset were subsequently evaluated in an independent cohort composed of 433 patients who were treated with RC and PLND for clinically non-metastatic BCa between 1988 and 2003. Distant recurrences were separetely evaluated for the two studied cohort. Cox regression analyses evaluating the risk of developing distant recurrence after RC were built. RESULTS In the primary cohort composed by 1,081 patients 445 (41.2%) received a perioperative BT. The median follow up was 52 months (Interquartile range: 44-61 months). Overall, 277 (25.6%) patients incurred in distant recurrence during follow up period. In the second cohort composed by 433 patients treated at a single institution 183 (42.3%) patients received perioperative BT. The median follow up was 83 months (Interquartile range: 75-91 months). Distant recurrence during the follow up period were recorded in 127 (28.3%) patients. One, three and five-years distant recurrence rates were 81% vs. 85%, 65% vs. 70% and 60% vs. 68% for patients who received intraoperative vs. no BT transfusion (p=0.03). One, three and five-years distant recurrence rates were 81% vs. 85%, 64% vs. 70% and 53% vs. 68% for patients who received postoperative vs. no BT transfusion (p=0.4). Similar findings were observed in the validation studied cohort (all p =0.05). At multivariable analyses predicting distant recurrences, BT were not related to an increased risk to incur in distant recurrence (all p=0.2) or different recurrence patterns in both studied cohorts. CONCLUSIONS BT administration in RC patients is not associated with different pattern or higher rates of distant recurrences when compared to patients who not received BT. New data are needed to investigate mechanisms behind the association between BT and survival in RC patients. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e776 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Marco Moschini More articles by this author Andrea Gallina More articles by this author Marco Bandini More articles by this author Paolo Dell'Oglio More articles by this author Giovanni La Croce More articles by this author Giusy Burgio More articles by this author Agostino Mattei More articles by this author Rocco Damiano More articles by this author Vincenzo Mirone More articles by this author Alberto Briganti More articles by this author Francesco Montorsi More articles by this author Renzo Colombo More articles by this author Shahrokh Shariat More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Expression of epithelial and mesenchymal markers in invasive (ductal) breast carcinoma and nodal metastasis

Introduction The phenomenon, Epithelial-mesenchymal transition (EMT) has been shown to enable epithelial cells to acquire a mesenchymal phenotype facilitating cancer cell mobilization. Evidence in favour has been derived predominantly from cancer cell lines and/or animal model studies. The objectives of this study were to observe E-cadherin and vimentin expression patterns in invasive (ductal) breast carcinoma-no special type (BCa) and corresponding metastatic lymph nodes (mLNs) and to compare the expression of these markers in BCa with and without metastasis using clinical samples. Methodology Tissues of 24 metastatic BCa (mBCa) with mLNs and 17 non metastatic BCa (nmBCa) obtained from the Department of Pathology, Faculty of Medicine, Peradeniya were included. Immunohistochemical expression of E-cadherin (epithelial cell adhesion membrane marker) and vimentin (mesenchymal cytoplasmic marker) was observed on all BCas and mLNs. Ten random high-power fields (10x40) of 100 cells each were assessed to determine the percentage of positive cells . The mean expression of markers was compared between mBCa and nmBCa by independent sample T-test and mBCa and mLN by paired sample T-test. Results The mean E-cadherin expression was 70.54% (27.67%-97.67%) in mBCa, 86.40% (63.33%-96.67%) in nmBCa and 89.95% (46.33%-100%) in mLNs. The mean vimentin expression was 6.54% (2.37%-13.87%) in mBCa, 5.39% (2.12%- 9.77%) in nmBCa and 1.28% (0.13%-8.25%) in mLNs. The E-cadherin expression was significantly lower in mBCa compared to nmBCa (p=0.002) and in mBCa compared to mLNs (p=0.000). Vimentin expression was not significant between mBCA and nmBCa (p=0.176). Higher vimentin expression in mBCa compared to mLNs was statistically significant (p=0.000). Discussion and conclusion The significantly lower expression of E-cadherin in mBCa compared to nmBCa suggests that loss of epithelial cell properties promotes metastasis. Significantly lower E-cadherin and significantly higher vimentin expressions in mBCa compared to mLNs is supportive of EMT in BCa. The reversed pattern is noted in nodal BCa metastasis suggesting the possibility of mesenchymal-epithelial transition of metastatic cancer cells in the lymph node.

Abstract 217: Mitochondrial reprogramming regulated cancer pathway in triple negative breast cancer

Abstract Compared to other subtypes of tumors, triple negative breast cancers (TN BCa) currently suffer from limited knowledge on its etiology and treatment options. Transmitochondrial cybrids (cybrid) and multiple OMICs approaches were used to understand mitochondrial reprogramming and mitochondria-regulated cancer pathways in TN BCa. Analysis of cybrids and established BCa cell lines showed that metastatic TN BCa maintain high levels of ATP through fatty acid β-oxidation and activate Src oncoprotein by its autophosphorylation. Inhibition and induction of β-oxidation including the shRNA mediated knockdown strategies, and analysis of patient derived xenograft (PDX) models confirmed the role of mitochondrial β-oxidation in Src activation and metastasis. Analysis of BCa clinical data further reaffirmed the role of mitochondrial β-oxidation in Src regulation and their significance in BCa metastasis. This study is innovative in showing the mitochondrial reprogramming mediated regulation of a major cancer pathway by its post-translation modification. Citation Format: Jun H. Park, Sajna Vithayathil, Danli Wu, Vasanta Putluri, Pi-Lin Sung, Efrosini Tsouko, Vadiraja B. Bhat, Cristian Coarfa, Daniel E. Frigo, Michael T. Lewis, Arun Sreekumar, Patricia Yotnda, Chad J. Creighton, Nagireddy Putluri, Lee-Jun C. Wong, Benny A. Kaipparettu. Mitochondrial reprogramming regulated cancer pathway in triple negative breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 217.

Abstract 3055: Regulation of mitochondria-nuclear crosstalk in triple negative breast cancer

Abstract Driver pathways of triple negative breast cancer (TN BCa) is still poorly understood. Thus, it is important to identify the underlying mechanisms of TN BCa progression. Importantly, African American and Hispanic patients are more likely to be diagnosed of BCa at a younger age, have a higher probability of developing TN BCa. They also diagnosed with a more advanced stage of the disease compared to Caucasian women. Src oncognenic pathway is one of the major tumor driving mechanisms in TN BCa. Src pathway is frequently over-expressed in TN BCa and Src inhibitors are one of their current treatments of choices. However, recent single drug therapy Phase-II trials with Src inhibitors failed to control unselected metastatic TN BCa. This raises some important questions on the underlying mechanism in the regulation of Src in TN BCa especially in aggressive metastatic BCa. Mitochondria, a semiautonomous organelle in cells, play an important role in cellular energy metabolism, free radical generation, and apoptosis. Mitochondria-nuclear crosstalk is a bidirectional pathway of communication between mitochondria and nucleus that influences many cellular and organismal activities. This crosstalk can regulate several oncogenic pathways involved in tumorigenesis. Using transmitochondrial cybrid (cybrid) technology, we generated different cybrid models under common nuclear background of TN BCa. Mitochondria from cells of different cancer potential including benign breast epithelium, moderately and highly metastatic breast cancer cell lines were used to understand cancer mitochondria regulated tumor pathways. Extensive analysis of cybrid models as well as confirmation in parental cell lines and other tumor models suggested that autophosphorylation of c-Src is regulated by mitochondrial tumor characteristics. Ongoing studies using knock-down and over expression approaches focus on the role of specific mitochondrial proteins that are responsible for mitochondria-nuclear crosstalk and the regulation oncopathways in TN BCa. Citation Format: Jun H. Park, Sajna A. Vithayathil, Nagireddy Putluri, Efrosini Tsouko, Taraka R. Donti, Daniel E. Frigo, Chad J. Creighton, Michael T. Lewis, Arun Sreekumar, Lee-Jun Wong, Benny A. Kaipparettu. Regulation of mitochondria-nuclear crosstalk in triple negative breast cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3055. doi:10.1158/1538-7445.AM2015-3055

Delineating breast cancer cell interactions with engineered bone microenvironments

The mechanisms leading to colonization of metastatic breast cancer cells (BCa) in the skeleton are still not fully understood. Here, we demonstrate that mineralized extracellular matrices secreted by primary human osteoblasts (hOBM) modulate cellular processes associated with BCa colonization of bone. A panel of four BCa cell lines of different bone-metastatic potential (T47D, SUM1315, MDA-MB-231, and the bone-seeking subline MDA-MB-231BO) was cultured on hOBM. After 3 days, the metastatic BCa cells had undergone morphological changes on hOBM and were aligned along the hOBM's collagen type I fibrils that were decorated with bone-specific proteins. In contrast, nonmetastatic BCa cells showed a random orientation on hOBM. Atomic force microscopy-based single-cell force spectroscopy revealed that the metastatic cell lines adhered more strongly to hOBM compared with nonmetastatic cells. Function-blocking experiments indicated that β1 -integrins mediated cell adhesion to hOBM. In addition, metastatic BCa cells migrated directionally and invaded hOBM, which was accompanied by enhanced MMP-2 and -9 secretion. Furthermore, we observed gene expression changes associated with osteomimickry in BCa cultured on hOBM. As such, osteopontin mRNA levels were significantly increased in SUM1315 and MDA-MB-231BO cells in a β1 -integrin-dependent manner after growing for 3 days on hOBM compared with tissue culture plastic. In conclusion, our results show that extracellular matrices derived from human osteoblasts represent a powerful experimental platform to dissect mechanisms underlying critical steps in the development of bone metastases.

Abstract P5-03-01: Role of Aromatase and Its Inhibitor in Breast Cancer-Induced Tumorigenesis and Bone Metastasis

Abstract Aromatase (Aro) is the rate-limiting enzyme that catalyzes the final step in estrogen (E2) biosynthesis. An important strategy to treat hormone-dependent BCa is suppression of estrogen receptor (ER) action by antiestrogens or aromatase inhibitors (AI). Letrozole is a very specific and potent AI. In postmenopausal women, the ovaries cease to make E2 but concentration of E2 in their BCa tissue are maintained at a certain level for survival and proliferation of BCa cells, which is dependent on local E2 formation catalyzed by Aro. Although BCa cells have been shown to express Aro, the local E2 is largely produced by adipose stromal cells in the breast. This raises the question of how ER positive (ER+) metastatic BCa cells survive after they enter blood circulation, where E2 level is very low. We cultured human ER+ BCa CAMA-1, Aro-transfected MCF-7 and ZR-75-1 (ZR) cells in suspension to mimic circulating BCa cells. Interestingly, suspension culture increased Aro expression, suggesting circulating ER+ BCa may up-regulate intracrine E2 activity for survival after leaving the E2-rich adipose stroma at primary site. The expression of Aro also enhances cell proliferation and supplementation of testosterone (T), the substrate of Aro, stimulates this proliferation further. Notably, while these cells show an increased rate of apoptosis in suspension than in adherent culture, addition of T in suspension culture significantly suppressed the rate of apoptosis and addition of letrozole blocked the T-induced cell survival in suspension culture. To investigate the importance of intracrine E2 in promoting tumorigenesis and metastasis, we implanted Aro-expressing ZR cells orthotopically and intracardiacally (I.C.) into female athymic mice; vector-transfected ZR cells were used as control. While control ZR cells were incapable of forming tumors without E2 supplementation, Aro-expressing cells generated orthotopic tumors with no E2 supplementation after 3-weeks of inoculation. More interestingly, mice with I.C. inoculated Aro-expressing cells also presented distant bone metastasis in the mandible and tibiae/femora after 2-weeks of inoculation, detected by whole mouse fluorescence and bioluminescence imaging as the cells were stably transfected with a luciferase and GFP expression vector. To determine whether growth of orthotopic tumors can be inhibited by systemic administration of an AI, we treated the mice in one group with letrozole at 10 mg/mouse/day and the other group with the vehicle as control after the average tumor volume reached 150 mm3. After 3-weeks, the tumor burden in the letrozole treatment group reduced significantly while tumor burden in the control group increased continuously. Our studies show that suspension culture increases expression of Aro mRNA in several ER+ BCa cell lines, which likely results in increased intracrine E2 signaling and contributes to the survival of these BCa cellsin suspension. This provides a mechanistic insight into how ER+ BCa cells may survive the low E2 condition in circulation and subsequently induce distant metastasis as observed in the I.C. model. Our study provides an important foundation for future investigation on how hormone-dependent BCa cells up-regulate Aro expression in circulation and induce bone metastasis. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-03-01.