Factors associated with breast cancer mortality after local recurrence

Anti-cancer effectiveness of a novel ceramide analog on chemo-sensitive and chemo-resistant breast cancers

INTRODUCTION

Ceramides are known to show anti-cancer activity. A novel ceramide analog, (S,E)-3-hydroxy-2-(2-hydroxybenzylidene)amino-N-tetradecylpropanamide (analog 315) was developed as part of a larger study focused on finding more effective breast cancer treatments.

OBJECTIVE

To assess whether analog 315 shows any or a combination of the following effects in breast cancer cells in vitro: inhibiting proliferation, inducing apoptosis, and altering protein expression. Also, to determine whether it inhibits chemo-resistant breast cancer tumor growth in vivo mouse model.

METHODS

In vitro cell proliferation and apoptosis after treatment with analog 315 were assessed in three breast cancer cell lines (MCF-7, MCF-7TN-R, and MDA-MB-231) and reported. Protein expression was assessed by microarray assay. For the in vivo studies, chemo-resistant breast cancer cells were used for tumor development in two groups of mice (treated and control). Analog 315 (25 mg/kg/day) or control (dimethyl sulfoxide) was administered intraperitoneally for 7 days. Effects of analog 315 on inhibiting the growth of chemo-resistant breast cancer tumors after treatment are reported.

RESULTS

Analog 315 reduced MCF-7TN-R chemo-resistant tumor burden (volume and weight) in mice. Liver metastasis was observed in control mice, but not in the treated animals. Ki-67, a proliferation marker for breast cancer cells, increased significantly ( P  < 0.05) in control tumor tissue. In vitro studies showed that analog 315 inhibited cell proliferation, altered protein expression and induced apoptosis in all three breast cancer cell lines studied, of which the effects on MCF-7TN-R cells were the most significant.

CONCLUSION

Analog 315 reduced tumor growth in chemo-resistant breast cancer, inhibited cell proliferation, altered protein expression, and induced apoptosis in all three cell lines studied.

Protocol of the HISTOTHERM study: assessing the response to hyperthermia and hypofractionated radiotherapy in recurrent breast cancer

Introduction

Breast cancer is globally the leading cancer in women, and despite the high 5-year survival rate the most frequent cause of cancer related deaths. Surgery, systemic therapy and radiotherapy are the three pillars of curative breast cancer treatment. However, locoregional recurrences frequently occur after initial treatment and are often challenging to treat, amongst others due to high doses of previous radiotherapy treatments. Radiotherapy can be combined with local hyperthermia to sensitize tumor cells to radiation and thereby significantly reduce the required radiation dose. Therefore, the combination treatment of mild local hyperthermia, i.e. locally heating of the tissue to 39-43°C, and re-irradiation with a reduced total dose is a relevant treatment option for previously irradiated patients. The mechanisms of this effect in the course of the therapy are to date not well understood and will be investigated in the HISTOTHERM study.

Methods and analyses

Patients with local or (loco)regional recurrent breast cancer with macroscopic tumors are included in the study. Local tumor control is evaluated clinically and histologically during the course of a combination treatment of 60 minutes mild superficial hyperthermia (39 - 43°C) using water-filtered infrared A (wIRA) irradiation, immediately followed by hypofractionated re-irradiation with a total dose of 20-24 Gy, administered in weekly doses of 4 Gy. Tumor and tumor stroma biopsies as well as blood samples will be collected prior to treatment, during therapy (at a dose of 12 Gy) and in the follow-up to monitor therapy response. The treatment represents the standard operating procedure for hyperthermia plus re-irradiation. Various tissue and blood-based markers are analyzed. We aim at pinpointing key mechanisms and markers for therapy response which may help guiding treatment decisions in future. In addition, quality of life in the course of treatment will be assessed and survival data will be evaluated.

Registration

The study is registered at the German Clinical Trials Register, Deutsches Register Klinischer Studien (DRKS00029221).

Predicting early breast cancer recurrence from histopathological images in the Carolina Breast Cancer Study

Approaches for rapidly identifying patients at high risk of early breast cancer recurrence are needed. Image-based methods for prescreening hematoxylin and eosin (H&E) stained tumor slides could offer temporal and financial efficiency. We evaluated a data set of 704 1-mm tumor core H&E images (2-4 cores per case), corresponding to 202 participants (101 who recurred; 101 non-recurrent matched on age and follow-up time) from breast cancers diagnosed between 2008-2012 in the Carolina Breast Cancer Study. We leveraged deep learning to extract image information and trained a model to identify recurrence. Cross-validation accuracy for predicting recurrence was 62.4% [95% CI: 55.7, 69.1], similar to grade (65.8% [95% CI: 59.3, 72.3]) and ER status (66.3% [95% CI: 59.8, 72.8]). Interestingly, 70% (19/27) of early-recurrent low-intermediate grade tumors were identified by our image model. Relative to existing markers, image-based analyses provide complementary information for predicting early recurrence.

Prognosis after Local Recurrence in Patients with Early-Stage Breast Cancer Treated without Chemotherapy

Background: Many women with early-stage breast cancer are predicted to be at sufficiently low risk for recurrence that they may forego chemotherapy. Nevertheless, some low-risk women will experience a local recurrence, and for them the risk of death increases significantly thereafter. The utility of initiating chemotherapy at the time of local recurrence has not been adequately addressed. The purpose of this study is to identify, in a hospital-based series of patients with early-stage breast cancer who were not treated with chemotherapy, those factors which predict death post local recurrence. Methods: We identified 135 women who were diagnosed with early-stage breast cancer (node-negative, <5 cm) and who did not receive chemotherapy at diagnosis and who developed a local recurrence. They were diagnosed between 1987 and 2000 and treated at Women’s College Hospital. For each patient, we abstracted information on the initial cancer (age at diagnosis, tumour size, tumour grade, ER status, PR status, HER2 status, lympho-vascular invasion, type of surgery, use of radiotherapy, tamoxifen and chemotherapy), the time from initial diagnosis to local recurrence and treatment at recurrence. The Kaplan–Meier method was used to estimate the ten-year actuarial risk of breast cancer death post recurrence. A Cox proportional hazards model was used to estimate multivariate hazard ratios for the various factors. Results: Among the 135 women in the cohort, the mean time from initial diagnosis to local recurrence was 7.8 years (range: 0.3 to 22.6 years). A total of 38 of the 135 women (28.1%) died of breast cancer a mean of 5.3 years after experiencing the local recurrence (range: 0.3 to 17 years). The ten-year breast cancer survival post local recurrence was 71% and the 15-year survival was 65%. In a multivariate analysis, it was found that factors that were significantly associated with death after local recurrence were (1) PR-negative status, (2) young age at diagnosis (<40 years) and (3) time to local recurrence less than 2 years. Nine percent of women received chemotherapy at the time of local recurrence. Conclusions: For breast cancer patients with a low baseline risk of mortality, the risk of death after an isolated local recurrence is substantial. Systemic treatment at the time of local recurrence needs further study.

Modelling multiple time-scales with flexible parametric survival models

BACKGROUND

There are situations when we need to model multiple time-scales in survival analysis. A usual approach in this setting would involve fitting Cox or Poisson models to a time-split dataset. However, this leads to large datasets and can be computationally intensive when model fitting, especially if interest lies in displaying how the estimated hazard rate or survival change along multiple time-scales continuously.

METHODS

We propose to use flexible parametric survival models on the log hazard scale as an alternative method when modelling data with multiple time-scales. By choosing one of the time-scales as reference, and rewriting other time-scales as a function of this reference time-scale, users can avoid time-splitting of the data.

RESULT

Through case-studies we demonstrate the usefulness of this method and provide examples of graphical representations of estimated hazard rates and survival proportions. The model gives nearly identical results to using a Poisson model, without requiring time-splitting.

CONCLUSION

Flexible parametric survival models are a powerful tool for modelling multiple time-scales. This method does not require splitting the data into small time-intervals, and therefore saves time, helps avoid technological limitations and reduces room for error.

Interactive exploration of a global clinical network from a large breast cancer cohort

Despite unprecedented amount of information now available in medical records, health data remain underexploited due to their heterogeneity and complexity. Simple charts and hypothesis-driven statistics can no longer apprehend the content of information-rich clinical data. There is, therefore, a clear need for powerful interactive visualization tools enabling medical practitioners to perceive the patterns and insights gained by state-of-the-art machine learning algorithms. Here, we report an interactive graphical interface for use as the front end of a machine learning causal inference server (MIIC), to facilitate the visualization and comprehension by clinicians of relationships between clinically relevant variables. The widespread use of such tools, facilitating the interactive exploration of datasets, is crucial both for data visualization and for the generation of research hypotheses. We demonstrate the utility of the MIIC interactive interface, by exploring the clinical network of a large cohort of breast cancer patients treated with neoadjuvant chemotherapy (NAC). This example highlights, in particular, the direct and indirect links between post-NAC clinical responses and patient survival. The MIIC interactive graphical interface has the potential to help clinicians identify actionable nodes and edges in clinical networks, thereby ultimately improving the patient care pathway.

Triple-negative breast cancer drug resistance, durable efficacy, and cure: How advanced biological insights and emerging drug modalities could transform progress

INTRODUCTION

Triple-negative breast cancer (TNBC) is a heterogeneous disease characterized by the lack of estrogen receptor (ER), progesterone receptor (PR) and epidermal growth factor receptor 2 (HER2) and often associated with poor survival outcomes. The backbone of current treatments for TNBC relies on chemotherapy; however, resistance to cytotoxic agents is a commonly encountered hurdle to overcome.

AREAS COVERED

: Current understanding on the mechanisms involved in TNBC chemoresistance is evaluated and novel potential actionable targets and recently explored modalities for carrying and delivering chemotherapeutics are highlighted.

EXPERT OPINION

: A comprehensive identification of both genomic and functional TNBC signatures is required for a more definite categorization of the patients in order to prevent insensitivity to chemotherapy and therefore realize the full potential of precision-medicine approaches. In this scenario, cell-line-derived xenografts (CDX), patient-derived xenografts (PDX), patient-derived orthotopic xenografts (PDOX) and patient-derived organoids (PDO) are indispensable experimental models for evaluating the efficacy of drug candidates and predicting the therapeutic response. The combination of increasingly sensitive "omics" technologies, computational algorithms and innovative drug modalities may accelerate the successful translation of novel candidate TNBC targets from basic research to clinical settings, thus contributing to reach optimal clinical output, with lower side effects and reduced resistance.

Mortality After Late Breast Cancer Recurrence in Denmark

PURPOSE

Late breast cancer (BC) recurrence (ie, ≥ 10 years after primary diagnosis) may have a more favorable prognosis than earlier recurrence. We investigated the risk of BC death after late recurrence, identified prognostic factors, and compared survival after early and late recurrence.

METHODS

Using the Danish Breast Cancer Group and other nationwide databases, we identified women with early or late BC recurrence during 2004-2018, who were alive 6 months after recurrence. We followed them until BC death, death from other causes, emigration, 10 years, or December 31, 2018, whichever came first. We calculated mortality rates (MRs) per 1,000 person-years (PY) and cumulative BC mortality, for early versus late recurrence, and by characteristics of the primary tumor and the late recurrence. Using Cox regression, we calculated adjusted hazard ratios (HRs) for BC death, accounting for death from other causes as competing risks.

RESULTS

Among 2,004 patients with late recurrence, 721 died of BC with a median survival time of 10 years (MR = 84.8 per 1,000 PY; 10-year cumulative mortality = 50%). Among 1,528 patients with early recurrence, 1,092 BC deaths occurred with a median survival time of 4 years (MR = 173.9 per 1,000 PY; 10-year cumulative mortality = 72%). We observed a lower hazard of BC-specific death among patients who developed late compared with early recurrence (hazard ratio = 0.72; 95% CI, 0.62 to 0.85). Advanced stage at primary diagnosis, distant metastases, adjuvant treatment for locoregional recurrence, and systemic treatment for distant recurrence were associated with increased mortality after late recurrence. Breast-conserving surgery at primary diagnosis, locoregional recurrence, and surgery for recurrence were associated with lower mortality after late recurrence.

CONCLUSION

Patients with late recurrence had more favorable prognosis than patients with early recurrence. The localization of recurrent disease was the main prognostic factor for BC death.

Circulating Cell-free DNA in Serum as a Marker for the Early Detection of Tumor Recurrence in Breast Cancer Patients

BACKGROUND/AIM

Circulating cell-free DNA (cfDNA) isolated from serum by noninvasive procedures can serve as a potential biomarker for the early detection of many cancers. The aim of this study was to implement a simple, yet effective quantitative method for measuring the cfDNA in serum and to investigate the relationship between cfDNA and the occurrence of recurrence in breast cancer (BrCa) patients.

PATIENTS AND METHODS

A total of 240 cases were selected, which comprised different subtypes of BrCa patients and control individuals. We selected 20 serum samples from patients which showed recurrence after 4-7 years of disease-free survival. SYBR green was used as a reporter molecule to estimate the amount of cfDNA in these serum samples.

RESULTS

A global Wilcoxon analysis was performed to compare the cfDNA abundance between non-recurrent and recurrent patients. The amount of cfDNA was higher in recurrent patients (recurrent vs. non-recurrent ratio=1.3; p=0.03; AUC=0.76) compared to non-recurrent patients. The data between normal/healthy controls and non-recurrent patients indicated no significant differences (n=20 in each group, healthy to non-recurrent ratio=1.03; p=0.20; AUC=0.61).

CONCLUSION

We implemented a straightforward one-step technique to measure the amount of cfDNA in serum, which can translate into a clinical diagnostic tool in the near future. The high levels of cfDNA in the serum of recurrent BrCa patients compared to non-recurrent BrCa patients indicates a possible uncovered role for circulating genetic information, which either contributes to the cancer recurrence phenomenon or at the very least, serves as an identifier for the potential of recurrence.

Late Recurrence Following Early Breast Cancer

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in the Journal of Clinical Oncology, to patients seen in their own clinical practice.

Association between recurrent breast cancer and phthalate exposure modified by hormone receptors and body mass index

The association between phthalate exposure and breast cancer remains controversial. We performed a prospective patient cohort design to explore the interaction between creatinine-corrected urinary phthalate metabolites and hormone receptors as well as body mass index (BMI) on recurrent breast cancer. In this follow-up study, 636 female breast cancer patients and 45 new recurrent cases diagnosed for a total of 1576.68 person-years of follow-up were recruited. Mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) was negatively associated with breast cancer recurrence, with adjusted hazard ratio (aHR) 3rd vs. 1st quartile of 0.15 (95% CI 0.04–0.51). The MEOHP presented as a non-monotonic dose–response (NMDR) curve, being U-shaped. In the stratification of hormone receptors, MEOHP still exhibited a U-shaped dose–response curve. The third quartile of MEOHP showed significant lowest recurrent risk in the status of ER-positive (aHR 0.18, 95% CI 0.05–0.66), PR-negative (aHR 0.14, 95% CI 0.03–0.63), and HER2-negative (aHR 0.24, 95% CI 0.08–0.76). Whether in BMI < 25 or in BMI ≥ 25, the third quartile of MEOHP was negatively associated with recurrent breast cancer, and there was a negative interaction on an additive scale between MEOHP and BMI (p_interaction = 0.042). The association between MEOHP and recurrent breast cancer was modified by hormone receptors and BMI.

The impact of isolated local recurrence on long-term outcome in early-breast cancer patients after breast-conserving therapy

PURPOSE

To analyse the prognostic impact of isolated local recurrence (ILR) on long-term outcome for early-breast cancer patients treated with breast-conserving therapy.

MATERIAL AND METHODS

The data of the EORTC 22881-10882 'boost-no boost' and 22922-10925 'IM-MS' trials were used to analyse the prevalence and outcome following ILR. A multistate model described the impact of intermediate events on long-term outcomes, taking into account various prognostic factors. This model was used to predict long-term outcomes after ILR.

RESULTS

Of the 8367 patients included, 726 experienced an ILR, 11.6% of them within the first 2 years and 30.0% after 10 years. Ten-year cumulative breast cancer mortality rates after ILR were 58.2% in patients with an ILR within 2 years, 31.0% for ILR between 2 and 4 years, 17.6% in patients with an ILR between 4 and 10 years, and 29.7% for ILR after year 10 (p < 0.001). The multistate model showed that when tumour-free, younger breast cancer patients had a higher probability of developing ILR compared to older patients. Shorter time to ILR was associated with a higher chance to develop distant metastases (DM), and a shorter time to development of DM were associated with an increased hazard of breast cancer-related death. The multistate model enabled prediction of long-term outcome based on individual patient covariates, length of follow-up without recurrence and timing of ILR since randomisation.

CONCLUSIONS

Outcome of early-breast cancer changed not only according to baseline risk factors but also according to the presence of intermediate events, time to these events, and subsequent follow-up without any further events.

TrkA Interacts with and Phosphorylates STAT3 to Enhance Gene Transcription and Promote Breast Cancer Stem Cells in Triple-Negative and HER2-Enriched Breast Cancers

Simple Summary

Breast cancer is the leading cancer in American women. Due to the inherent aggressiveness of triple-negative and HER2-enriched breast cancers, it is imperative to identify novel molecular targets for therapeutic intervention. Due to their abnormal activities in metastatic breast cancers, JAK2–STAT3 and TrkA pathways have been individually implicated in aggressive breast tumors. However, their co-activation and signaling interactions have not been thoroughly investigated. Therefore, our study aimed to elucidate the extent of crosstalk between JAK2–STAT3 and TrkA signaling pathways and its impact on breast cancer. Our data revealed a novel interaction between TrkA and STAT3, and that this interaction results in STAT3 phosphorylation and activation by TrkA, leading to enhanced stemness gene expression and stem cell renewal. We further found that the co-activation of JAK2–STAT3 and TrkA pathways is correlated with shorter time to develop overall and organ-specific metastasis, suggesting that this signaling crosstalk underlies the aggressiveness of triple-negative and HER2-enriched breast cancers.

Abstract

JAK2–STAT3 and TrkA signaling pathways have been separately implicated in aggressive breast cancers; however, whether they are co-activated or undergo functional interaction has not been thoroughly investigated. Herein we report, for the first time that STAT3 and TrkA are significantly co-overexpressed and co-activated in triple-negative breast cancer (TNBC) and HER2-enriched breast cancer, as shown by immunohistochemical staining and data mining. Through immunofluorescence staining–confocal microscopy and immunoprecipitation–Western blotting, we found that TrkA and STAT3 co-localize and physically interact in the cytoplasm, and the interaction is dependent on STAT3-Y705 phosphorylation. TrkA–STAT3 interaction leads to STAT3 phosphorylation at Y705 by TrkA in breast cancer cells and cell-free kinase assays, indicating that STAT3 is a novel substrate of TrkA. β-NGF-mediated TrkA activation induces TrkA–STAT3 interaction, STAT3 nuclear transport and transcriptional activity, and the expression of STAT3 target genes, SOX2 and MYC. The co-activation of both pathways promotes breast cancer stem cells. Finally, we found that TNBC and HER2-enriched breast cancer with JAK2–STAT3 and TrkA co-activation are positively associated with poor overall metastasis-free and organ-specific metastasis-free survival. Collectively, our study uncovered that TrkA is a novel activating kinase of STAT3, and their co-activation enhances gene transcription and promotes breast cancer stem cells in TNBC and HER2-enriched breast cancer.

Factors Associated With Breast Cancer Surgery Delay Within a Coordinated Multihospital Community Health System: When Does Surgical Delay Impact Outcome?

BACKGROUND

Multiple factors influence the time elapsed between diagnosis of breast cancer and surgical extirpation of the primary tumor. The disease-free interval between resection of primary breast cancer and first evidence of recurrence is predictive of mortality. We aimed to determine patient, disease, and treatment factors associated with a delay in time to surgery (TTS) and identify the point when prolonged TTS negatively impacts disease-free survival.

PATIENTS AND METHODS

Cancer registry and electronic medical record data for patients with breast cancer who underwent surgery as first course of treatment during 2006-2016 were retrospectively reviewed. Patients undergoing surgery in ≤30 vs. 31-60 vs. >60 days of initial diagnosis were compared. Kaplan-Meier survival analyses with Cox proportional hazards were performed to evaluate impact of time from breast cancer diagnosis to definitive therapeutic surgery on breast cancer recurrence or death (all-cause).

RESULTS

Overall, 4462 patients were analyzed, 43.4% of whom underwent surgery beyond 30 days. The following factors were associated with TTS >30 days: age <50, non-Hispanic White race/ethnicity, commercial or health exchange/Medicaid insurance, diagnosis of noninvasive disease (i.e., ductal carcinoma in situ), had breast magnetic resonance imaging before definitive surgery, underwent total mastectomy (especially if immediate reconstruction, particularly if autologous, was performed), and did not receive adjuvant therapies (P < .001 for all). After adjusting for relevant variables, significant predictors of recurrence/death included a TTS >60 days, increased patient age, higher breast cancer stage, and triple-negative biomarker expression.

CONCLUSION

Risk of recurrence or death is not compromised until TTS exceeds 60 days after initial breast cancer diagnosis.

An Overview of PARP Inhibitors for the Treatment of Breast Cancer

Loss-of-function mutations in BRCA1 and BRCA2 are detected in at least 5% of unselected patients with breast cancer (BC). These BC susceptibility genes encode proteins critical for DNA homologous recombination repair (HRR). This review provides an update on oral poly(ADP-ribose) polymerase (PARP) inhibitors for the treatment of BC. Olaparib and talazoparib are PARP inhibitors approved as monotherapies for deleterious/suspected deleterious germline BRCA-mutated, HER2-negative BC. Olaparib is approved in the USA for metastatic BC and in Europe for locally advanced/metastatic BC. Talazoparib is approved for locally advanced/metastatic BC in the USA and Europe. In phase 3 trials, olaparib and talazoparib monotherapies demonstrated significant progression-free survival benefits compared with chemotherapy. Common toxicities were effectively managed by supportive treatment and dose interruptions/reductions. Veliparib combined with platinum-based chemotherapy has also shown promise for locally advanced/metastatic BC in a phase 3 trial. Differences in efficacy and safety across PARP inhibitors (olaparib, talazoparib, veliparib, niraparib, rucaparib) may relate to differences in potency of PARP trapping on DNA and cytotoxic specificity. PARP inhibitors are being investigated in early BC, in novel combinations, and in patients without germline BRCA mutations, including those with somatic BRCA mutations and other HRR gene mutations. Ongoing phase 2/3 studies include PARP inhibitors combined with immune checkpoint inhibitors for the treatment of triple-negative BC. Wider access to testing for BRCA and other mutations, and to genetic counseling, are required to identify patients who could benefit from PARP inhibitor therapy. The advent of PARP inhibitors has potential benefits for BC treatment beyond the locally advanced/metastatic setting.

Factors associated with breast cancer recurrence and survival at Sangre Grande Hospital, Trinidad

PURPOSE

The aim of this study is to determine the demographic, pathological, and treatment-related factors that predict recurrence and survival in a Trinidadian cohort of breast cancer patients.

METHODS

The inclusion criteria for this study were female, over 18 years, and with a primary breast cancer diagnosis confirmed by a biopsy report occurring between 2010 and 2015 at Sangre Grande Hospital, Trinidad. Univariate associations with 5-year recurrence-free survival and 5-year overall survival were calculated using the Kaplan-Meier method for categorical variables and Cox Proportional Hazards for continuous variables. A multivariate model for prediction of recurrence and survival was determined using Cox regression.

RESULTS

For the period 2010-2015, 202 records were abstracted. Five-year overall survival and recurrence-free survival rates were found to be 74.3% and 56.4%, respectively. Median times from first suspicious finding to date of biopsy report, date of surgery, and date of chemotherapy were 63 days, 125 days, and 189 days, respectively. In the univariate analysis, age (p = 0.038), stage (p < 0.001), recurrence (p = 0.035), surgery (p = 0.016), ER (p < 0.001) status, PR status (p < 0.001), and subtype (p < 0.001) were significantly associated with survival. Additionally, stage (p = 0.004), N score (p = 0.002), ER (p = 0.028) status, PR (p = 0.018) status, and subtype (p = 0.025) were significantly associated with recurrence. In the Cox multivariate model, Stage 4 was a significant predictor of survival (HR 6.77, 95% CI [0.09-2.49], p = 0.047) and N3 score was a significant predictor of recurrence (HR 4.47, 95% CI [1.29-15.54], p = 0.018).

CONCLUSION

This study reports a 5-year breast cancer survival rate of 74.3%, and a recurrence-free survival rate of 56.4% in Trinidad for the period 2010-2015.

Antiproliferative and Antimigration Activities of Fluoro-Neplanocin A via Inhibition of Histone H3 Methylation in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is among the most aggressive and potentially metastatic malignancies. Most affected patients have poor clinical outcomes due to the lack of specific molecular targets on tumor cells. The upregulated expression of disruptor of telomeric silencing 1-like (DOT1L), a histone methyltransferase specific for the histone H3 lysine 79 residue (H3K79), is strongly correlated with TNBC cell aggressiveness. Therefore, DOT1L is considered a potential molecular target in TNBC. Fluoro-neplanocin A (F-NepA), an inhibitor of S-adenosylhomocysteine hydrolase, exhibited potent antiproliferative activity against various types of cancer cells, including breast cancers. However, the molecular mechanism underlying the anticancer activity of F-NepA in TNBC cells remains to be elucidated. We determined that F-NepA exhibited a higher growth-inhibitory activity against TNBC cells relative to non-TNBC breast cancer and normal breast epithelial cells. Moreover, F-NepA effectively downregulated the level of H3K79me2 in MDA-MB-231 TNBC cells by inhibiting DOT1L activity. F-NepA also significantly inhibited TNBC cell migration and invasion. These activities of F-NepA might be associated with the upregulation of E-cadherin and downregulation of N-cadherin and Vimentin in TNBC cells. Taken together, these data highlight F-NepA as a strong potential candidate for the targeted treatment of high-DOT1L-expressing TNBC.

HIF-2α regulates CD44 to promote cancer stem cell activation in triple-negative breast cancer via PI3K/AKT/mTOR signaling

BACKGROUND

Breast cancer is a common malignant tumor that seriously threatens women’s health. Breast cancer stem cell (CSC)-like cell population may be the main factor for breast cancer metastasis. Therefore, targeted therapy for CSCs has great potential significance. Hypoxia-inducible factor is a transcription factor widely expressed in tumors. Studies have shown that down-regulation of the hypoxia signaling pathway inhibits tumor stem cell self-renewal and increases the sensitivity of stem cells to radiotherapy and chemotherapy mediated by hypoxia-inducible factor-2α (HIF-2α). However, the specific mechanism remains unclear and further research is necessary.

AIM

To investigate the effect of HIF-2α down-regulation on stem cell markers, microsphere formation, and apoptosis in breast cancer cell line MDA-MB-231 under hypoxia and its possible mechanism.

METHODS

Immunohistochemistry was used to detect the expression of HIF-2α and CD44 in triple-negative breast cancer (TNBC) and non-TNBC tissues. Double-labeling immunofluorescence was applied to detect the co-expression of HIF-2α and CD44 in MDA-MB-231 cells and MCF-7 cells. HIF-2α was silenced by RNA interference, and the expression of CD44 and transfection efficiency were detected by real-time fluorescent quantitative PCR. Further, flow cytometry, TdT-mediated X-dUTP nick end labeling, and mammosphere formation assays were used to evaluate the effect of HIF-2α on CSCs and apoptosis. The possible mechanisms were analyzed by Western blot.

RESULTS

The results of immunohistochemistry showed that HIF-2α was highly expressed in both TNBC and non-TNBC, while the expression of CD44 in different molecular types of breast cancer cells was different. In in vitro experiments, it was found that HIF-2α and CD44 were expressed almost in the same cell. Compared with hypoxia + negative-sequence control, HIF-2α small interfering ribonucleic acid transfection can lower the expression of HIF-2α and CD44 mRNA(P < 0.05), increase the percentage of apoptotic cells (P < 0.05), and resulted in a reduction of CD44⁺/CD24⁻ population (P < 0.05) and mammosphere formation (P < 0.05) in hypoxic MDA-MB-231 cells. Western blot analysis revealed that phosphorylated protein-serine-threonine kinase (p-AKT) and phosphorylated mammalian target of rapamycin (p-mTOR) levels in MDA-MB-231 decreased significantly after HIF-2α silencing (P < 0.05).

CONCLUSION

Down-regulation of HIF-2α expression can inhibit the stemness of human breast cancer MDA-MB-231 cells and promote apoptosis, and its mechanism may be related to the CD44/phosphoinosmde-3-kinase/AKT/mTOR signaling pathway.

Semiparametric Model for Bivariate Survival Data Subject to Biased Sampling

To better understand the relationship between patient characteristics and their residual survival after an intermediate event such as the local cancer recurrence, it is of interest to identify patients with the intermediate event and then analyze their residual survival data. One challenge in analyzing such data is that the observed residual survival times tend to be longer than those in the target population, since patients who die before experiencing the intermediate event are excluded from the identified cohort. We propose to jointly model the ordered bivariate survival data using a copula model and appropriately adjusting for the sampling bias. We develop an estimating procedure to simultaneously estimate the parameters for the marginal survival functions and the association parameter in the copula model, and use a two-stage expectation-maximization algorithm. Using empirical process theory, we prove that the estimators have strong consistency and asymptotic normality. We conduct simulations studies to evaluate the finite sample performance of the proposed method. We apply the proposed method to two cohort studies to evaluate the association between patient characteristics and residual survival.

Chest resurfacing with a reverse abdominoplasty flap for invasive breast cancer recurrence

We present a patient with recurrent breast cancer requiring massive resection of the upper chest. Management included a reverse abdominoplasty flap to resurface the anterior chest wall, with acceptable aesthetic outcomes, and adjuvant chemotherapy. RA is a simple and versatile coverage option in patients with high risk of disease recurrence.

Is invasion a necessary step for metastases in breast cancer?

PURPOSE

To review the empirical evidence to support the conventional (sequential) model of breast cancer progression, which is based on the paradigm that cancer passes through several stages, including an in situ stage prior to an invasive stage, and thereafter (in some cases) disseminates to the lymph nodes and distant organs.

METHODS

We review the cancer literature of the last 50 years which relates to the prevention of invasive breast cancer (through radiotherapy or surgery) and reductions in the mortality for breast cancer.

RESULTS

For both invasive cancers and DCIS, the literature indicates that prevention of in-breast invasive recurrences does not prevent death from breast cancer. Moreover, the presence of residual cancer cells in the breast after breast-conserving surgery does not compromise the cure rate.

CONCLUSION

We propose an alternate (parallel) model of breast cancer wherein there is a small pool of cancer stem cells which have metastatic potential from their inception and which disseminate synchronously through several routes-to the breast stroma, to the lymph nodes and to distant organs. Cancer cells which disseminate to the breast give rise to cells which make up the bulk of the tumour mass but these are not the source of the distant metastases.

Factors predictive of mortality in a cohort of women surgically treated for breast cancer from 1997 to 2014

OBJECTIVE

To determine whether previously reported factors predictive of breast cancer mortality are effectively linked with mortality, particularly breast-cancer-specific mortality.

METHODS

In a prospective study, clinical, surgical, and follow-up data were assessed for consecutive patients with breast cancer who underwent surgery between 1997 and 2014 at two centers in Barcelona, Spain. Predictors of mortality were assessed by multivariate analysis.

RESULTS

Overall, 2134 patients were treated for 2206 breast tumors. Overall mortality was 15.0% (n=319), and breast-cancer-specific mortality was 9.0% (n=191). On multivariate analysis, the most significant factors associated with breast-cancer-specific mortality were clinical stage, inmunohistochemical profile, locoregional relapse, and lymphovascular invasion (all P<0.001). Age at onset, participation in the mass-screening program, histologic grade, and multicentricity were not significant. Patients with three or more positive axillary nodes sustained a specific mortality significantly higher than did node-negative patients or those with fewer than three positive nodes.

CONCLUSION

Factors predictive of breast cancer mortality were clinical stage, locoregional relapse, molecular classification, lymphovascular invasion, and neoadjuvant chemotherapy. As a single factor, nodal disease becomes relevant only when three or more lymph nodes are involved.

Development of a model to predict breast cancer survival using data from the National Cancer Data Base

BACKGROUND

With the large amounts of data on patient, tumor, and treatment factors available to clinicians, it has become critically important to harness this information to guide clinicians in discussing a patient's prognosis. However, no widely accepted survival calculator is available that uses national data and includes multiple prognostic factors. Our objective was to develop a model for predicting survival among patients diagnosed with breast cancer using the National Cancer Data Base (NCDB) to serve as a prototype for the Commission on Cancer's "Cancer Survival Prognostic Calculator."

PATIENTS AND METHODS

A retrospective cohort of patients diagnosed with breast cancer (2003-2006) in the NCDB was included. A multivariable Cox proportional hazards regression model to predict overall survival was developed. Model discrimination by 10-fold internal cross-validation and calibration was assessed.

RESULTS

There were 296,284 patients for model development and internal validation. The c-index for the 10-fold cross-validation ranged from 0.779 to 0.788 after inclusion of all available pertinent prognostic factors. A plot of the observed versus predicted 5 year overall survival showed minimal deviation from the reference line.

CONCLUSION

This breast cancer survival prognostic model to be used as a prototype for building the Commission on Cancer's "Cancer Survival Prognostic Calculator" will offer patients and clinicians an objective opportunity to estimate personalized long-term survival based on patient demographic characteristics, tumor factors, and treatment delivered.

Comparison of Clinical and Pathological Differences of Breast Cancer Patients under 35 and above 55 Years of Age

OBJECTIVE

In this study, we aimed to evaluate the clinical, pathologic and management differences between breast cancer patients under 35 years of age and postmenopausal patients above 55 years of age.

MATERIALS AND METHODS

Patients who were operated on for breast cancer between November 2003 and March 2013 in our hospital were retrospectively analyzed. Patients were separated into two Groups according their age; Group 1 (<35 years) and Group 2 (>55 years).

RESULTS

94 patients with breast cancer, 45 patients in Group 1 and 49 patients in Group 2, were included in the study. The mean follow-up was 51 (19-121) months and 50 (19-120) months in Groups 1 and 2, respectively. Stages of breast cancer at the time of diagnosis were similar between the two groups. The groups were similar in terms of rates of re-excision (p=0.42), local recurrence (p=0.34) and solid organ metastases (p=0.182). The number of oncoplastic and reconstructive procedures were higher in Group 1 (p=0.04). Regarding pathological results, the rate of grade 3 tumors, those with Ki-67>12 and triple negative breast cancer were found to be higher in Group 1. In addition, the number of patients receiving chemotherapy was significantly higher in Group 1 (p=0.03).

CONCLUSION

Oncologic results were similar between young patients and postmenopausal patients. Nevertheless, tumor biology was found to be worse in young patients. In addition, oncoplastic and reconstructive approaches were significantly higher in young patients.

Oncologic outcome after local recurrence of chondrosarcoma: Analysis of prognostic factors

BACKGROUND

Literature on outcome after local recurrence (LR) in chondrosarcoma is scarce and better appreciation of prognostic factors is needed.

OBJECTIVES

(1) To evaluate post-LR oncologic outcomes of disease-specific survival and subsequent LR and (2) to identify prognostic factors for post-LR oncologic outcomes.

PATIENTS AND METHODS

Review of 28 patients with locally recurrent chondrosarcoma from the original cohort of 150 patients, who were treated surgically with or without adjuvants between 1982 and 2011, was performed. Mean age was 46 years (range, 21-73) which included 20 males and 8 females with mean follow up of 8.4 ± 7.5 years (range, 1.2-31.0).

RESULTS

Post-LR survival at 5 years was 58.6 ± 10.3%. Age greater than 50 years (P = 0.011) and LR occurring within 1 year of primary surgery (P = 0.011) independently predicted poor survival. Seven patients suffered subsequent LR, which was significantly affected by surgical margin for LR (P = 0.038).

CONCLUSION

Long-term survival of locally recurrent chondrosarcoma is achievable in a substantial number of patients. Older age at onset of LR and shorter interval from primary surgery to LR identifies high risk patients for poor post-LR survival while, wide surgical margins at LR surgery reduces the risk of subsequent LR.

Factors associated with the incidence of local recurrences of breast cancer in women who underwent conservative surgery

Conservative surgery is considered the procedure of choice for women who are affected by early stage tumours. The local recurrence of cancer as a consequence of breast tissue conservation is a growing concern. This study aimed to describe the sociodemographic and clinical profiles of women who had local recurrences of breast cancer after conservative surgery and to examine the associations between sociodemographic and clinical variables and the incidence of tumour recurrence in these women. The retrospective cohort included 880 women who were diagnosed with breast cancer and underwent conservative surgery between January 2000 and December 2010. Recurrences occurred in 60 patients, and the mean age of the women at diagnosis was 48.8 years. Predictive factors for local recurrence were young age (<39 years) (P = 0.028 and OR = 10.93), surgical margin involvement (P = 0.001 and OR = 3.66), and Her-2 overexpression (P = 0.045 and OR = 1.94). The establishment of sociodemographic and clinical characteristics might help to select optimum treatments, which is a crucial challenge for public health in Brazil, especially with regard to reductions of surgery and hospitalisation expenditures in the Unified Health System (Sistema Único de Saúde—SUS).