Systemic Therapy Advances for HER2-Positive and Triple Negative Breast Cancer: What the Surgeon Needs to Know

Neoadjuvant systemic therapy (NST) was initially reserved for unresectable patients however it has been increasingly used to facilitate breast conservation, downstage the axilla, and inform adjuvant therapy decisions based on response. For patients with HER2+ and triple-negative breast cancer (TNBC), clinical trials have resulted in the ability to individualize treatment regimens. For HER2+ breast cancer, de-escalation of neoadjuvant regimens to minimize cytotoxic chemotherapy and de-escalation or escalation of adjuvant regimens based on response have been effective. For TNBC, the approval of the combination of chemotherapy plus immunotherapy in the neoadjuvant setting has resulted in a major practice shift and opened the door to many additional treatment questions including de-escalation of the chemotherapy backbone or the adjuvant regimen. For both HER2+ and TNBC, most patients are treated with NST except those with very small tumors. Efforts are also being made to optimally identify patients with T1c tumors who may benefit from more aggressive NST. For patients treated according to or enrolled in NST de-escalation trials, breast conservation (even those who become eligible based on response to NST) and sentinel lymph node biopsy when cN0 at the completion of NST are safe and feasible. Continued involvement of surgeons and multidisciplinary teams in the design and reporting of trials will streamline their adoption into clinical practice. Surgeons need to remain aware of ongoing systemic therapy trials to appropriately select patients for NST and plan for appropriate post-neoadjuvant surgical care.

DDX58 deficiency leads to triple negative breast cancer chemotherapy resistance by inhibiting Type I IFN-mediated signalling apoptosis

INTRODUCTION

Triple-negative breast cancer (TNBC) is characterized by its aggressive nature and absence of specific therapeutic targets, necessitating the reliance on chemotherapy as the primary treatment modality. However, the drug resistance poses a significant challenge in the management of TNBC. In this study, we investigated the role of DDX58 (DExD/H-box helicase 58), also known as RIG-I, in TNBC chemoresistance.

METHODS

The relationship between DDX58 expression and breast cancer prognosis was investigated by online clinical databases and confirmed by immunohistochemistry analysis. DDX58 was knockout by CRISPR-Cas9 system (DDX58-KO), knockdown by DDX58-siRNA (DDX58-KD), and stably over expressed (DDX58-OE) by lentivirus. Western blotting, immunofluorescence and qPCR were used for related molecules detection. Apoptosis was analyzed through flow cytometry (Annexin V/7AAD apoptosis assay) and Caspase 3/7 activity assay.

RESULTS

Patients with lower expression of DDX58 led to lower rate of pathological complete response (pCR) and worse prognosis by online databases and hospital clinical data. DDX58-KD cells showed multiple chemo-drugs resistance (paclitaxel, doxorubicin, 5-fluorouracil) in TNBC cell lines. Similarly, DDX58-KO cells also showed multiple chemo-drugs resistance in a dosage-dependent manner. In the CDX model, tumours in the DDX58-KO group had a 25% reduction in the tumour growth inhibition rate (IR) compared to wild-type (WT) group after doxorubicin (Dox) treatment. The depletion of DDX58 inhibited proliferation and promoted the migration and invasion in MDA-MB-231 cells. The findings of our research indicated that DDX58-KO cells exhibit a reduction in Dox-induced apoptosis both in vivo and in vitro. Mechanistically, Dox treatment leads to a significant increase in the expression of double-stranded RNAs (dsRNAs) and activates the DDX58-Type I interferon (IFN) signaling pathway, ultimately promoting apoptosis in TNBC cells.

DISCUSSION

In the process of TNBC chemotherapy, the deficiency of DDX58 can inhibit Dox-induced apoptosis, revealing a new pathway of chemotherapy resistance, and providing a possibility for developing personalized treatment strategies based on DDX58 expression levels.

Leveraging hypoxia in triple-negative breast cancer as a promising treatment strategy

Current treatment strategies for triple-negative breast cancer (TNBC) are based upon conventional chemotherapy, immunotherapy, or a combination of both. The treatment regimen for chemotherapy is often a combination of two or more drugs, either dose dense or low dose for synergy. Anthracyclines, alkylating agents, antimicrotubule agents, and antimetabolites for early-stage TNBC; and antimetabolites, non-taxane microtubule inhibitors, and cross-linker platinums for late-stage TNBC are usually administered in the clinical setting. Newer options for patients with advanced TNBC, such as poly (ADP-ribose) polymerase (PARP) inhibitors and immune checkpoint inhibitors, have recently emerged for cases where surgery is not a viable option and the disease has metastasized. This review outlines the current trends in hypoxia-inspired treatment strategies for TNBC with a focus on clinical trials.

Molecular Biology Mechanisms and Emerging Therapeutics of Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that is conventionally characterized by the absence of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2), accounting for approximately 15-20% of all breast cancers. Compared to other molecular phenotypes, TNBC is typically associated with high malignancy and poor prognosis. Cytotoxic agents have been the mainstay of treatment for the past few decades due to the lack of definitive targets and limited therapeutic interventions. However, recent developments have demonstrated that TNBC has peculiar molecular classifications and biomarkers, which provide the possibility of evolving treatment from basic cytotoxic chemotherapy to an expanding domain of targeted therapies. This review presents a framework for understanding the current clinical experience surrounding molecular biology mechanisms in TNBC (Figure 1). Including immunotherapy, polymerase (PARP) and PI3K/AKT pathway inhibitors, antibody-drug conjugates, and androgen receptor (AR) blockade. Additionally, the role of miRNA therapeutics targeting TNBC and potential strategies targeting cancer stem cells (CSCs) are discussed and highlighted. As more and more treatments arise on the horizon, we believe that patients with TNBC will have a new sense of hope.

DNA Damage Inducer Mitoxantrone Amplifies Synergistic Mild-Photothermal Chemotherapy for TNBC via Decreasing Heat Shock Protein 70 Expression

Patients with triple-negative breast cancer (TNBC) have the worst clinical outcomes when compared to other subtypes of breast cancer. Nanotechnology-assisted photothermal therapy (PTT) opens new opportunities for precise cancer treatment. However, thermoresistance caused by PTT, as well as uncertainty in the physiological metabolism of existing phototherapeutic nanoformulations, severely limit their clinical applications. Herein, based on the clinically chemotherapeutic drug mitoxantrone (MTO), a multifunctional nanoplatform (MTO-micelles) is developed to realize mutually synergistic mild-photothermal chemotherapy. MTO with excellent near-infrared absorption (≈669 nm) can function not only as a chemotherapeutic agent but also as a photothermal transduction agent with elevated photothermal conversion efficacy (ƞ = 54.62%). MTO-micelles can accumulate at the tumor site through the enhanced permeability and retention effect. Following local near-infrared irradiation, mild hyperthermia (<50 °C) assists MTO in binding tumor cell DNA, resulting in chemotherapeutic sensitization. In addition, downregulation of heat shock protein 70 (HSP70) expression due to enhanced DNA damage can in turn weaken tumor thermoresistance, boosting the efficacy of mild PTT. Both in vitro and in vivo studies indicate that MTO-micelles possess excellent synergetic tumor inhibition effects. Therefore, the mild-photothermal chemotherapy strategy based on MTO-micelles has a promising prospect in the clinical transformation of TNBC treatment.

Additional capecitabine use in early-stage triple negative breast cancer patients receiving standard chemotherapy: a new era? A meta-analysis of randomized controlled trials

Background

The efficiency of capecitabine has been proven in early-stage triple negative breast cancer (eTNBC) with residue invasive tumor (non-pCR) after standard neoadjuvant chemotherapy (NACT). However, for those unselected eTNBC patients without screening from NACT (i.e., newly diagnosed eTNBC patients undergoing breast surgery followed by adjuvant systemic therapy), the value of capecitabine has still remains unclear. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate whether additional capecitabine in eTNBC patients could improve clinical outcomes.

Methods

Seven RCTs (USO 01062, FinXX, GEICAM/2003, CREATE-X, CIBOMA/2004, CBCSG-010 and SYSUCC-001) were identified in online databases until December 2020 and included in the meta-analysis. We extracted the survival data including disease/relapse-free survival (DFS/RFS) and overall survival (OS), and utilized the STATA software to calculate the summarized hazard ratios (HRs) and 95% confidence intervals (95%CIs).

Results

A total of 3329 eTNBC patients were enrolled in this meta-analysis, with 1640 receiving standard neo−/adjuvant chemo-regimes alone, and the other 1689 receiving an additional capecitabine use, respectively. Both DFS and OS were significantly improved with the addition of capecitabine, and the benefits remained consistent in those unselected eTNBC patients without screening from NACT. Subgroup analysis further proved that this improvement in DFS was significant in both nodal negative and positive patients. Similar benefits are also found across menopausal status (both pre- and post-menopause). Regarding toxicity, the hand-foot syndrome and neutropenia are the most common capecitabine related adverse events, and are mostly tolerable.

Conclusions

The present meta-analysis of RCTs demonstrates for the first time that adding capecitabine to standard chemo-regimens could improve both DFS and OS in unselected eTNBC patients, and this benefit remains consistent regardless of nodal status and menopausal status, which may lead eTNBC therapy into a new era.

CDK4/6 inhibitors: A potential therapeutic approach for triple negative breast cancer

Triple negative breast cancer (TNBC) cells lack expression of the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER-2). Thus, TNBC does not respond to hormone-based therapy. TNBC is also an aggressive subtype associated with poorer prognoses compared to other breast cancers. Conventional chemotherapeutics are used to manage TNBC although systemic relapse is common with limited benefits being reported as well as adverse events being documented. Here, we discuss current therapies for TNBC in the neo- and adjuvant settings, as well as recent advancements in the targeting of PD-L1-positive tumors and inclusion of PARP inhibitors for TNBC patients with BRCA mutations. The recent development of cyclin-dependent kinase (CDK) 4/6 inhibitors in ER-positive breast cancers has demonstrated significant improvements in progression free survival in patients. Here, we review preclinical data of CDK 4/6 inhibitors and describe current clinical trials assessing these in TNBC disease.

Bioactive nanotherapeutic trends to combat triple negative breast cancer

The management of aggressive breast cancer, particularly, triple negative breast cancer (TNBC) remains a formidable challenge, despite treatment advancement. Although newer therapies such as atezolizumab, olaparib, and sacituzumab can tackle the breast cancer prognosis and/or progression, but achieved limited survival benefit(s). The current research efforts are aimed to develop and implement strategies for improved bioavailability, targetability, reduce systemic toxicity, and enhance therapeutic outcome of FDA-approved treatment regimen. This review presents various nanoparticle technology mediated delivery of chemotherapeutic agent(s) for breast cancer treatment. This article also documents novel strategies to employ cellular and cell membrane cloaked (biomimetic) nanoparticles for effective clinical translation. These technologies offer a safe and active targeting nanomedicine for effective management of breast cancer, especially TNBC.

Evaluation of Complete Pathological Regression after Neoadjuvant Chemotherapy in Triple-Negative Breast Cancer Patients with BRCA1 Founder Mutation Aided Bayesian A/B Testing Approach

The aim of this study was to evaluate the probability of pathologic complete regression (pCR) by the BRCA1 gene mutation status in patients with triple-negative breast cancer (TNBC) treated with neoadjuvant chemotherapy. The study involved 143 women (mean age 55.4 ± 13.1 years) with TNBC. The BRCA1 mutation was observed in 17% of the subjects. The most commonly used (85.3%) chemotherapy regimen was four cycles of adriamycine and cyclophosphamide followed by 12 cycles of paclitaxel (4AC + 12T). The differences between clinico-pathological factors by BRCA1 status were estimated. Odds ratios and 95% confidence intervals for pCR vs. non-pCR were calculated using logistic regression. The probability distribution of pCR based on BRCA1 status was estimated using beta distributions. The presence of T3-T4 tumours, cancer in stages II and III, lymphovascular invasion, and the use of chemotherapy schedules other than 4AC + 12T significantly decreased the odds of pCR. It was established that there was a 20% chance that pCR in patients with the BRCA1 mutation was 50% or more times as frequent than in patients without the mutation. Thus, the BRCA1 mutation can be a predictive factor for pCR in patients with TNBC.

Design, synthesis and structure-activity relationship study of novel urea compounds as FGFR1 inhibitors to treat metastatic triple-negative breast cancer

Triple-negative breast cancer (TNBC) is an aggressive type of cancer characterized by higher metastatic and reoccurrence rates, where approximately one-third of TNBC patients suffer from the metastasis in the brain. At the same time, TNBC shows good responses to chemotherapy, a feature that fuels the search for novel compounds with therapeutic potential in this area. Recently, we have identified novel urea-based compounds with cytotoxicity against selected cell lines and with the ability to cross the blood-brain barrier in vivo. We have synthesized and analyzed a library of more than 40 compounds to elucidate the key features responsible for the observed activity. We have also identified FGFR1 as a molecular target that is affected by the presence of these compounds, confirming our data using in silico model. Overall, we envision that these compounds can be further developed for the potential treatment of metastatic breast cancer.

Effects of folic acid withdrawal on transcriptomic profiles in murine triple-negative breast cancer cell lines

We have previously shown that withdrawal of folic acid led to metabolic reprogramming and a less aggressive phenotype in a mouse cell model of triple-negative breast cancer (TNBC). Herein, we evaluate the effects of folic acid withdrawal on transcriptomic profiles in these cells. Murine cell lines were originally derived from a pool of spontaneous mammary tumors grown in MMTV-Wnt1 transgenic mice. Based on their differential molecular characteristics and metastatic potential, these cell lines were previously characterized as non-metastatic epithelial (E-Wnt), non-metastatic mesenchymal (M-Wnt) and metastatic mesenchymal (metM-Wnt^liver) cells. Using custom two-color 180K Agilent microarrays, we have determined gene expression profiles for three biological replicates of each subtype kept on standard medium (2.2 μM folic acid) or folic acid-free medium for 72 h. The analyses revealed that more genes were differentially expressed upon folic acid withdrawal in M-Wnt cells (1884 genes; Benjamini-Hochberg-adjusted P-value <0.05) compared to E-Wnt and metM-Wnt^liver cells (108 and 222 genes, respectively). Pathway analysis has identified that type I interferon signaling was strongly affected by folic acid withdrawal, with interferon-responsive genes consistently being upregulated upon folic acid withdrawal in M-Wnt cells. Of note, repressed interferon signaling has been established as one of the characteristics of aggressive human TNBC, and hence reactivation of this pathway may be a promising therapeutic approach. Overall, while our study indicates that the response to folic acid withdrawal varies by molecular subtype and cellular phenotype, it also underscores the necessity to further investigate one-carbon metabolism as a potential therapeutic means in the treatment of advanced TNBC.

A Sesquiterpenoid from Farfarae Flos Induces Apoptosis of MDA-MB-231 Human Breast Cancer Cells through Inhibition of JAK-STAT3 Signaling

Triple-negative breast cancers (TNBCs) are hard-to-treat breast tumors with poor prognosis, which need to be treated by chemotherapy. Signal transducer and activator of transcription 3 (STAT3) is a transcription factor involved in proliferation, metastasis, and invasion of cancer cells. Therefore, research on searching for promising compounds with metabolism that suppress phosphorylation or transcription of STAT3 in TNBC cells is important. Farfarae Flos is well known as a traditional medicine for treating inflammation. However, few studies have shown that sesquiterpenoids from Farfarae Flos have an anticancer effect. In this study, efficient separation methods and an MTT assay were conducted to isolate an anticancer compound from Farfarae Flos against TNBC MDA-MB-231 cells. Here, 7β-(3-Ethyl-cis-crotonoyloxy)-1α-(2-methylbutyryloxy)-3,14-dehydro-Z-notonipetranone (ECN), a compound isolated from Farfarae Flos showed a potent cytotoxic effect on MDA-MB-231 cells. ECN inhibited JAK–STAT3 signaling and suppressed the expression of STAT3 target genes. In addition, ECN induced apoptosis through both extrinsic and intrinsic pathways. Furthermore, we investigated that ECN inhibited the growth of tumors by intraperitoneal administration in mice injected with MDA-MB-231 cells. Therefore, ECN can be an effective chemotherapeutic agent for breast cancer treatment.

Antitumor properties of Salvianolic acid B against triple-negative and hormone receptor-positive breast cancer cells via ceramide-mediated apoptosis

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with limited treatment options. It is urgent to develop new therapeutics against this disease. Salvinolic acid B (Sal-B) is a leading bioactive component of Salvia miltiorrhiza Bunge, a well-known Chinese medicine for treating various diseases without appreciable adverse effects. To understand the antitumor properties of Sal-B against TNBC, we analyzed its effects on the cell viability, cell cycle and apoptosis of triple-negative MDA-MB-231 cells with the hormone receptor-positive MCF-7 cells as the control. The in vitro analysis showed that Sal-B could significantly reduce the cell viability and suppress the proliferation of both MDA-MB-231 and MCF-7 cells with decreased cyclin B1 expression, but with no noticeable cell cycle phase change. In mouse models, Sal-B markedly inhibited the growth, decreased the PCNA expression, and increased the cell apoptosis of MDA-MB-231 tumor xenografts. To understand the antitumor mechanisms, we analyzed the expression levels of ceramides, and anti-apoptotic (Bcl-xL and survivin) and pro-apoptotic (caspase-3 and caspase-8) proteins. We found that Sal-B enhanced the ceramide accumulation and inhibited the anti-apoptotic protein expression. Interestingly, the ceramide accumulation was accompanied by decreased expression of glucosylceramide and GM3 synthases, two key enzymes regulating ceramide metabolism. These findings indicate that Sal-B exerts its antitumor effects at least partially by inducing the ceramide accumulation and ceramide-mediated apoptosis via inhibiting the expression of glucosylceramide and GM3 synthases, which was independent of estrogen receptor α. Sal-B appears to be a promising therapeutic agent against TNBC.

Triple-Negative Breast Cancer: Who Should Receive Neoadjuvant Chemotherapy?

Progress in the treatment of triple-negative breast cancer remains an important challenge. Given the aggressive biology and high risk of distant recurrence, systemic chemotherapy is warranted in most patients. Neaodjuvant chemotherapy benefits patients with locally advanced disease by downsizing the tumor and increasing the probability of breast-conserving surgery. Clinical and pathologic responses provide important prognostic information, which makes neoadjuvant therapy an attractive approach for all patients with triple-negative breast cancer. Clinical research in the neoadjuvant setting is focused on improvement in pathologic complete response rates and outcomes of patients with residual disease.

Neoadjuvant chemotherapy in breast cancer: a dose-dense schedule in real life and putative role of PIK3CA mutations

Background

Dose-dense chemotherapy is one of the treatments of choice for neoadjuvant therapy in breast cancer (BC). Activating mutations in PIK3CA gene predict worse response to neoadjuvant chemotherapy for HER2-positive patients, while their role is less clearly defined for HER2-negative tumors.

Methods

We conducted a phase I/II study of neoadjuvant, sequential, dose-dense anthracycline/taxane chemotherapy, plus trastuzumab in HER2-positive patients and investigated the correlation of pre-treatment PIK3CA mutation status with pathologic complete response (pCR) and long-term outcome in a real-life setting.

Results

we established a dose-dense docetaxel recommended dose of 60 mg/m² and 65 mg/m², with or without trastuzumab, respectively, according to HER2-status, following dose-dense epirubicin-cyclophosphamide (90/600 mg/m²), every 2 weeks. The overall pCR rate was 21.4%; median disease-free survival (DFS) was 52 months and median overall survival (OS) was not yet reached. PIK3CA mutation status was not significantly associated with the pCR rate: 18% for both mutated and wild-type patients. The pCR rate was: 25% in the mutated and 24% in the wild-type (p 0.560) cohort of the HER2-positive subgroup; 33% both in the mutant and wild-type cohort of the triple-negative subgroup; no pCR neither in the mutant nor in the wild-type cohort of the HR-positive/HER2-negative subgroup. Among the HER2-positive population, a trend toward worse DFS was observed in case of mutation, as opposed to the triple negative population.

Conclusions

This study proposes an effective and safe neoadjuvant dose-dense anthracycline/taxane schedule and suggests that PIK3CA mutation analysis can be usefully performed in real-life clinical practice.

How shall we treat early triple-negative breast cancer (TNBC): from the current standard to upcoming immuno-molecular strategies

Triple-negative breast cancer (TNBC) is a long-lasting orphan disease in terms of little therapeutic progress during the past several decades and still the standard of care remains chemotherapy. Experimental discovery of molecular signatures including the ‘BRCAness’ highlighted the innate heterogeneity of TNBC, generating the diversity of TNBC phenotypes. As it contributes to enhancing genomic instability, it has widened the therapeutic spectrum of TNBC. In particular, unusual sensitivity to DNA damaging agents was denoted in patients with BRCA deficiency, suggesting therapeutic benefit from platinum and poly(ADP-ribose) polymerase inhibitors. However, regardless of enriched chemosensitivity and immunogenicity, majority of patients with TNBC still suffer from dismal clinical outcomes including early relapse and metastatic spread. Therefore, efforts into more precise and personalised treatment are critical at this point. Accordingly, the advance of multiomics has revealed novel actionable targets including PI3K-Akt-mTOR and epidermal growth factor receptor signalling pathways, which might actively participate in modulating the chemosensitivity and immune system. Also, TNBC has long been considered a potential protagonist of immunotherapy in breast cancer, supported by abundant tumour-infiltrating lymphocytes and heterogeneous tumour microenvironment. Despite that, earlier studies showed somewhat unsatisfactory results of monotherapy with immune-checkpoint inhibitors, consistently durable responses in responders were noteworthy. Based on these results, further combinatorial trials either with other chemotherapy or targeted agents are underway. Incorporating immune-molecular targets into combination as well as refining the standard chemotherapy might be the key to unlock the future of TNBC. In this review, we share the current and upcoming treatment options of TNBC in the framework of scientific and clinical data, especially focusing on early stage of TNBC.

Practical Approach to Triple-Negative Breast Cancer

Triple negative is a term applied to breast cancers that do not meaningfully express the estrogen or progesterone hormone receptors or overexpress the human epidermal growth factor receptor 2 tyrosine kinase. At present, the only proven method for systemic management of triple-negative breast cancer for both early-stage and metastatic settings is cytotoxic chemotherapy. Here, we provide a comprehensive review of management strategies that are best supported by available data. We also review recent advances most likely to affect treatment of triple-negative breast cancer in the coming years with particular emphasis on targeted agents, biologics, and immunotherapy.

Capecitabine in early breast cancer: A meta-analysis of randomised controlled trials

PURPOSE

Capecitabine is an effective therapy for metastatic breast cancer. Its role in early breast cancer is uncertain due to conflicting data from randomised controlled trials (RCTs).

METHODS

PubMed and major conference proceedings were searched to identify RCTs comparing standard chemotherapy with or without capecitabine in the neoadjuvant or adjuvant setting. Hazard ratios (HRs) for disease-free survival (DFS) and overall survival (OS), as well as odds ratios (ORs) for toxicities were extracted or calculated and pooled in a meta-analysis. Subgroup analysis compared triple-negative breast cancer (TNBC) to non-TNBC and whether capecitabine was given in addition to or in place of standard chemotherapy. Meta-regression was used to explore the influence of TNBC on OS.

RESULTS

Eight studies comprising 9302 patients were included. In unselected patients, capecitabine did not influence DFS (hazard ratio [HR] 0.99, p = 0.93) or OS (HR 0.90, p = 0.36). There was a significant difference in DFS when capecitabine was given in addition to standard treatment compared with in place of standard treatment (HR 0.92 versus 1.62, interaction p = 0.002). Addition of capecitabine to standard chemotherapy was associated with significantly improved DFS in TNBC versus non-TNBC (HR 0.72 versus 1.01, interaction p = 0.02). Meta-regression showed that adding capecitabine to standard chemotherapy was associated with improved OS in studies with higher proportions of patients with TNBC (R = -0.967, p = 0.007). Capecitabine increased grade 3/4 diarrhoea (odds ratio [OR] 2.33, p < 0.001) and hand-foot syndrome (OR 8.08, p < 0.001), and resulted in more frequent treatment discontinuation (OR 3.80, p < 0.001).

CONCLUSION

Adding capecitabine to standard chemotherapy appears to improve DFS and OS in TNBC, but increases adverse events in keeping with its known toxicity profile.

[High-dose chemotherapy as a strategy to overcome drug resistance in solid tumors]

The concept of high-doses chemotherapy was developed in the 1980s based on in vitro scientific observations. Exposure of tumor cells to increasing concentrations of alkylating agents resulted in increased cell death in a strong dose-response manner. Moreover, the acquired resistance of tumor cells could be overcome by dose intensification. In clinic, dose intensification of alkylating agents resulted in increased therapeutic responses, however associated with significant hematological toxicity. Following the development of autologous stem cells transplantation harvesting from peripheral blood, the high-doses of chemotherapy, initially associated with marked toxic effects, could be more easily tolerated. As a result, the approach was evaluated in different types of solid tumors, including breast, ovarian and germ cell tumors, small cell lung carcinoma, soft tissue sarcomas and Ewing sarcoma. To date, high-doses chemotherapy with hematopoietic stem cells support is only used as a salvage therapy to treat poor prognosis germ cell tumors patients with chemo-sensitive disease. Regarding breast and ovarian cancer, high-doses chemotherapy should be considered only in the context of clinical trials. However, intensive therapy as an approach to overcome resistance to standard treatments is still relevant. Numerous efforts are still ongoing to identify novel therapeutic combinations and active treatments to improve patients' responses.

BRCA1-like profile predicts benefit of tandem high dose epirubicin-cyclophospamide-thiotepa in high risk breast cancer patients randomized in the WSG-AM01 trial

BRCA1 is an important protein in the repair of DNA double strand breaks (DSBs), which are induced by alkylating chemotherapy. A BRCA1-like DNA copy number signature derived from tumors with a BRCA1 mutation is indicative for impaired BRCA1 function and associated with good outcome after high dose (HD) and tandem HD DSB inducing chemotherapy. We investigated whether BRCA1-like status was a predictive biomarker in the WSG AM 01 trial. WSG AM 01 randomized high-risk breast cancer patients to induction (2× epirubicin-cyclophosphamide) followed by tandem HD chemotherapy with epirubicin, cyclophosphamide and thiotepa versus dose dense chemotherapy (4× epirubicin-cyclophospamide followed by 3× cyclophosphamide-methotrexate-5-fluorouracil). We generated copy number profiles for 143 tumors and classified them as being BRCA1-like or non-BRCA1-like. Twenty-six out of 143 patients were BRCA1-like. BRCA1-like status was associated with high grade and triple negative tumors. With regard to event-free-survival, the primary endpoint of the trial, patients with a BRCA1-like tumor had a hazard rate of 0.2, 95% confidence interval (CI): 0.07-0.63, p = 0.006. In the interaction analysis, the combination of BRCA1-like status and HD chemotherapy had a hazard rate of 0.19, 95% CI: 0.067-0.54, p = 0.003. Similar results were observed for overall survival. These findings suggest that BRCA1-like status is a predictor for benefit of tandem HD chemotherapy with epirubicin-thiotepa-cyclophosphamide.

Low-Dose Oral Cyclophosphamide and Methotrexate Maintenance for Hormone Receptor-Negative Early Breast Cancer: International Breast Cancer Study Group Trial 22-00

PURPOSE

To evaluate the benefit of low-dose cyclophosphamide and methotrexate (CM) maintenance, which previously demonstrated antitumor activity and few adverse effects in advanced breast cancer, in early breast cancer.

PATIENTS AND METHODS

International Breast Cancer Study Group (IBCSG) Trial 22-00, a randomized phase III clinical trial, enrolled 1,086 women (1,081 intent-to-treat) from November 2000 to December 2012. Women with estrogen receptor- and progesterone receptor-negative (< 10% positive cells by immunohistochemistry) early breast cancer any nodal and human epidermal growth factor receptor 2 status, were randomly assigned anytime between primary surgery and 56 days after the first day of last course of adjuvant chemotherapy to CM maintenance (cyclophosphamide 50 mg/day orally continuously and methotrexate 2.5 mg twice/day orally on days 1 and 2 of every week for 1 year) or to no CM. The primary end point was disease-free survival (DFS), which included invasive recurrences, second (breast and nonbreast) malignancies, and deaths.

RESULTS

After a median of 6.9 years of follow-up, DFS was not significantly better for patients assigned to CM maintenance compared with patients assigned to no CM, both overall (hazard ratio [HR], 0.84; 95% CI, 0.66 to 1.06;P = .14) and in triple-negative (TN) disease (n = 814; HR, 0.80; 95% CI, 0.60 to 1.06). Patients with TN, node-positive disease had a nonstatistically significant reduced HR (n = 340; HR, 0.72; 95% CI, 0.49 to 1.05). Seventy-one (13%) of 542 patients assigned to CM maintenance did not start CM. Of 473 patients who received at least one CM maintenance dose (including two patients assigned to no CM), 64 (14%) experienced a grade 3 or 4 treatment-related adverse event; elevated serum transaminases was the most frequently reported (7%), followed by leukopenia (2%).

CONCLUSION

CM maintenance did not produce a significant reduction in DFS events in hormone receptor-negative early breast cancer. The trend toward benefit observed in the TN, node-positive subgroup supports additional exploration of this strategy in the TN, higher-risk population.

Triple-negative breast cancer: challenges and opportunities of a heterogeneous disease

Chemotherapy is the primary established systemic treatment for patients with triple-negative breast cancer (TNBC) in both the early and advanced-stages of the disease. The lack of targeted therapies and the poor prognosis of patients with TNBC have fostered a major effort to discover actionable molecular targets to treat patients with these tumours. Massively parallel sequencing and other 'omics' technologies have revealed an unexpected level of heterogeneity of TNBCs and have led to the identification of potentially actionable molecular features in some TNBCs, such as germline BRCA1/2 mutations or 'BRCAness', the presence of the androgen receptor, and several rare genomic alterations. Whether these alterations are molecular 'drivers', however, has not been clearly established. A subgroup of TNBCs shows a high degree of tumour-infiltrating lymphocytes that also correlates with a lower risk of disease relapse and a higher likelihood of benefit from chemotherapy. Proof-of-principle studies with immune-checkpoint inhibitors in advanced-stage TNBC have yielded promising results, indicating the potential benefit of immunotherapy for patients with TNBC. In this Review, we discuss the most relevant molecular findings in TNBC from the past decade and the most promising therapeutic opportunities derived from these data.

Granzyme B-based cytolytic fusion protein targeting EpCAM specifically kills triple negative breast cancer cells in vitro and inhibits tumor growth in a subcutaneous mouse tumor model

Triple-negative breast cancer (TNBC) is associated with poor prognosis and high prevalence among young premenopausal women. Unlike in other breast cancer subtypes, no targeted therapy is currently available. Overexpression of epithelial cell adhesion molecule (EpCAM) in 60% of TNBC tumors correlates with poorer prognosis and is associated with cancer stem cell phenotype. Thus, selective elimination of EpCAM(+) TNBC tumor cells is of clinical importance. Therefore, we constructed a fully human targeted cytolytic fusion protein, designated GbR201K-αEpCAM(scFv), in which an EpCAM-selective single-chain antibody fragment (scFv) is genetically fused to a granzyme B (Gb) mutant with reduced sensitivity to its natural inhibitor serpin B9. In vitro studies confirmed its specific binding, internalization and cytotoxicity toward a panel of EpCAM-expressing TNBC cells. Biodistribution kinetics and tumor-targeting efficacy using MDA-MB-468 cells in a human TNBC xenograft model in mice revealed selective accumulation of GbR201K-αEpCAM(scFv) in the tumors after i.v. injection. Moreover, treatment of tumor-bearing mice demonstrated a prominent inhibition of tumor growth of up to 50 % in this proof-of-concept study. Taken together, our results indicate that GbR201K-αEpCAM(scFv) is a promising novel targeted therapeutic for the treatment of TNBC.

Trastuzumab-Resistant Luminal B Breast Cancer Cells Show Basal-Like Cell Growth Features Through NF-κB-Activation

A major clinical problem in the treatment of breast cancer is mortality due to metastasis. Understanding the molecular mechanisms associated with metastasis should aid in designing new therapeutic approaches for breast cancer. Trastuzumab is the main therapeutic option for HER2+ breast cancer patients; however, the molecular basis for trastuzumab resistance (TZR) and subsequent metastasis is not known. Earlier, we found expression of basal-like molecular markers in TZR tissues from patients with invasive breast cancer.(( 1 )) The basal-like phenotype is a particularly aggressive form of breast cancer. This observation suggests that TZR might contribute to an aggressive phenotype. To understand if resistance to TZR can lead to basal-like phenotype, we generated a trastuzumab-resistant human breast cancer cell line (BT-474-R) that maintained human epidermal growth factor receptor 2 (HER2) overexpression and HER2 mediated signaling. Analysis showed that nuclear factor-kappa B (NF-κB) was constitutively activated in the BT-474-R cells, a feature similar to the basal-like tumor phenotype. Pharmacologic inhibition of NF-κB improved sensitivity of BT-474-R cells to trastuzumab. Interestingly, activation of HER2 independent NF-κB is not shown in luminal B breast cancer cells. Our study suggests that by activating the NF-κB pathway, luminal B cells may acquire a HER2+ basal-like phenotype in which NF-κB is constitutively activated; this notion is consistent with the recently proposed "progression through grade" or "evolution of resistance" hypothesis. Furthermore, we identified IKK-α/IKK-β and nuclear accumulation of RelA/p65 as the major determinants in the resistant cells. Thus our study additionally suggests that the nuclear accumulation of p65 may be a useful marker for identifying metastasis-initiating tumor cells and targeting RelA/p65 may limit metastasis of breast and other cancers associated with NF-κB activation.

High-Dose Chemotherapy and Autologous Hematopoietic Stem Cell Transplantation as Adjuvant Treatment in High-Risk Breast Cancer: Data from the European Group for Blood and Marrow Transplantation Registry

The aim of this retrospective study was to assess toxicity and efficacy of adjuvant high-dose chemotherapy (HDC) and autologous hematopoietic stem cell transplantation (AHSCT) in 583 high-risk breast cancer (BC) patients (>3 positive nodes) who were transplanted between 1995 and 2005 in Europe. All patients received surgery before transplant, and 55 patients (9.5%) received neoadjuvant treatment before surgery. Median age was 47.1 years, 57.3% of patients were premenopausal at treatment, 56.5% had endocrine-responsive tumors, 19.5% had a human epidermal growth factor receptor 2 (HER2)-negative tumor, and 72.4% had ≥10 positive lymph nodes at surgery. Seventy-nine percent received a single HDC procedure. Overall transplant-related mortality was 1.9%, at .9% between 2001 and 2005, whereas secondary tumor-related mortality was .9%. With a median follow-up of 120 months, overall survival and disease-free survival rates at 5 and 10 years in the whole population were 75% and 64% and 58% and 44%, respectively. Subgroup analysis demonstrated that rates of overall survival were significantly better in patients with endocrine-responsive tumors, <10 positive lymph nodes, and smaller tumor size. HER2 status did not affect survival probability. Adjuvant HDC with AHSCT has a low mortality rate and provides impressive long-term survival rates in patients with high-risk BC. Our results suggest that this treatment modality should be considered in selected high-risk BC patients and further investigated in clinical trials.

Prognostic value of different cut-off levels of Ki-67 in breast cancer: a systematic review and meta-analysis of 64,196 patients

A proliferative marker, expressed as the percentage of cells in a cell cycle, has been developed and used as a discriminant of more aggressive malignant phenotypes in early breast cancer (BC). The marker is usually expressed by the immunohistochemical staining of the cell cycle antigen Ki-67. It has not, however, yet been definitely evaluated, due to methodological concerns, which specific Ki-67 cut-off provide the strongest prognostic information in resected BC. We conducted a meta-analysis to explore the prognostic value of different cut-off levels of Ki-67 in terms of overall survival (OS) and disease-free survival (DFS) in early BC. The databases of PubMed, the ISI Web of Science, EMBASE, SCOPUS, the Cochrane Central Register of Controlled Trials, and CINHAL were used to identify the relevant literature. Data from studies reporting a hazard ratio (HR) and a 95 % confidence interval (CI) calculated as a multivariate analysis were pooled in a meta-analysis, with metaregression used to test for trends in predefined subgroups. All the statistical tests were 2-sided. Forty-one studies encompassing 64,196 BC patients were included in the analysis. Overall, n = 25 studies were available for the OS analysis. The pooled HR for high versus low Ki-67 was 1.57 (95 % CI 1.33-1.87, P < 0.00001). Twenty-nine studies were available for the DFS analysis. The pooled HR for high versus low Ki-67 was 1.50 (95 % CI 1.34-1.69, P < 0.00001). When a cut-off of Ki-67 staining ≥ 25 % was used, the pooled HR for OS was 2.05 (95 % CI 1.66-2.53, P < 0.00001), which was significantly different to studies where the cut-offs chosen were <25 %. In ER+ tumors, the HR for high versus low Ki-67 was similar and significant (HR = 1.51, 95 % CI 1.25-1.81, P < 0.0001). We conclude that Ki-67 has an independent prognostic value in terms of OS in BC patients. The Ki-67 threshold with the greatest prognostic significance is as yet unknown, but a cut-off >25 % is associated with a greater risk of death compared with lower expression rates.

An overview of triple-negative breast cancer

PURPOSE

Triple-negative breast cancer (TNBC) is a heterogeneous group of tumors comprising various breast cancers simply defined by the absence of estrogen receptor, progesterone receptor and overexpression of human epidermal growth factor receptor 2 gene. In this review, we discuss the epidemiology, risk factors, clinical characteristics and prognostic variables of TNBC, and present the summary of recommended treatment strategies and all other available treatment options.

METHODS

We performed a systematic literature search using Medline and selected those articles which seemed relevant for this review. In addition, the ClinicalTrials.gov was also scanned for ongoing trials.

RESULTS

TNBC accounts for 10-20 % of all invasive breast cancers and has been found to be associated with African-American race, younger age, higher grade and mitotic index, and more advanced stage at diagnosis. Locoregional treatment is similar to other invasive breast cancer subtypes and involves surgery-mastectomy with or without adjuvant radiotherapy or breast conservation followed by adjuvant radiotherapy. Due to lack of drug-targetable receptors, chemotherapy is the only recommended systemic treatment to improve disease outcome. TNBC is sensitive to chemotherapy as demonstrated by high pathological complete response rates achieved after neoadjuvant chemotherapy, and this approach also allows for breast-conserving surgery. The peak risk of relapse is at 3 years after surgery, thereafter recurrence risk rapidly decreases. Survival after metastatic relapse is shorter as compared to other breast cancer subtypes, treatment options are few and response rates are poor and lack durability. Important molecular characteristics have now been identified that can subdivide this group of breast cancers further and can provide alternative systemic therapies.

CONCLUSIONS

To improve therapeutic outcome of TNBC, reliable predictive biomarkers and newer drugs against the known molecular pathways are required.

New treatment strategies for patients with triple-negative breast cancer

PURPOSE OF REVIEW

Although patients with hormone receptor-positive and/or HER2-positive breast cancer benefit from endocrine and HER2-targeted agents in addition to combination chemotherapy regimens, patients with triple-negative breast cancer (TNBC) suffer from a particularly unfavorable prognosis particularly when not responding well to anthracycline-taxane chemotherapy. Novel treatment options are urgently needed to improve prognosis of these patients as well.

RECENT FINDINGS

Potential options for optimized therapy of patients with TNBC consist in, first, optimization of chemotherapy through optimization of chemotherapy regimens with may be reached through optimized (i.e., dose-dense) scheduling, second, optimization of chemotherapy through introduction of novel chemotherapy agents (such as platinum compounds as alternative of additional chemotherapy), third, identification and development of novel targeted agents, and fourth, identification of patients with or without response through biomarkers to individual treatments to allow for a more personalized treatment approach.

SUMMARY

We summarize recent findings for novel treatment options particularly focusing on platinum-based chemotherapy, potential novel targeted therapies such as antiangiogenic agents or inhibition of poly-A-ribose-polymerase, and prognostic/predictive biomarkers such as tumor-infiltrating lymphocytes or BRCA.

Intensive chemotherapy as salvage treatment for solid tumors: focus on germ cell cancer

Germ cell tumors present contrasting biological and molecular features compared to many solid tumors, which may partially explain their unusual sensitivity to chemotherapy. Reduced DNA repair capacity and enhanced induction of apoptosis appear to be key factors in the sensitivity of germ cell tumors to cisplatin. Despite substantial cure rates, some patients relapse and subsequently die of their disease. Intensive doses of chemotherapy are used to counter mechanisms of drug resistance. So far, high-dose chemotherapy with hematopoietic stem cell support for solid tumors is used only in the setting of testicular germ cell tumors. In that indication, high-dose chemotherapy is given as the first or late salvage treatment for patients with either relapsed or progressive tumors after initial conventional salvage chemotherapy. High-dose chemotherapy is usually given as two or three sequential cycles using carboplatin and etoposide with or without ifosfamide. The administration of intensive therapy carries significant side effects and can only be efficiently and safely conducted in specialized referral centers to assure optimum patient care outcomes. In breast and ovarian cancer, most studies have demonstrated improvement in progression-free survival (PFS), but overall survival remained unchanged. Therefore, most of these approaches have been dropped. In germ cell tumors, clinical trials are currently investigating novel therapeutic combinations and active treatments. In particular, the integration of targeted therapies constitutes an important area of research for patients with a poor prognosis.

Long-term survival of advanced triple-negative breast cancers with a dose-intense cyclophosphamide/anthracycline neoadjuvant regimen

BACKGROUND

Triple-negative (TN) breast cancers exhibit major initial responses to neoadjuvant chemotherapy, but generally have a poor outcome. Because of the lack of validated drug targets, chemotherapy remains an important therapeutic tool in these cancers.

METHODS

We report the survival of two consecutive series of 267 locally advanced breast cancers (LABC) treated with two different neoadjuvant regimens, either a dose-dense and dose-intense cyclophosphamide-anthracycline (AC) association (historically called SIM) or a conventional sequential association of cyclophosphamide and anthracycline, followed by taxanes (EC-T). We compared pathological responses and survival rates of these two groups and studied their association with tumours features.

RESULTS

Although the two regimens showed equivalent pathological complete response (pCR) in the whole population (16 and 12%), the SIM regimen yielded a non-statistically higher pCR rate than EC-T (48% vs 24%, P=0.087) in TN tumours. In the SIM protocol, DFS was statistically higher for TN than for non-TN patients (P=0.019), although we showed that the TN status was associated with an increased initial risk of recurrence in both regimens. This effect gradually decreased and after 2 years, TN was associated with a significantly decreased likelihood of relapse in SIM-treated LABC (hazard ratio (HR)=0.25 (95% CI: 0.07-0.86), P=0.028).

CONCLUSIONS

AC dose intensification treatment is associated with a very favourable long-term survival rate in TN breast cancers. These observations call for a prospective assessment of such dose-intense AC-based regimens in locally advanced TN tumours.

Targeted therapy in triple-negative metastatic breast cancer: a systematic review and meta-analysis

Objective

To perform a systematic review and meta-analysis of randomized controlled trials that compared the efficacy of targeted therapy to conventional chemotherapy (CT) in patients with metastatic triple-negative breast cancer (TNBC).

Methods

Several databases were searched, including Medline, Embase, LILACS, and CENTRAL. The primary end point was progression-free survival (PFS). We performed a meta-analysis of the published data. The results are expressed as hazard ratio (HR) or risk ratio, with their corresponding 95% confidence intervals (95% CIs).

Results

The final analysis included twelve trials comprising 2,054 patients with TNBC, which compared conventional CT alone against CT combined with targeted therapy (bevacizumab [Bev], sorafenib [Sor], cetuximab, lapatinib, and iniparib). PFS was superior in previously untreated patients with TNBC who received Bev plus CT compared to CT alone (fixed effect, HR 0.62, 95% CI 0.51–0.75; P<0.00001). Also, PFS was higher in one study that tested Bev plus CT combination in previously treated patients (HR 0.49, 95% CI 0.33–0.74; P=0.0006). Sor plus CT was also tested as first-line and second-line treatments. The pooled data of PFS favored the combination CT plus Sor (fixed effect, HR 0.69, 95% CI 0.49–0.98; P=0.04). Comparisons of iniparib plus CT also had a better PFS than CT alone (fixed effect, HR 0.75, 95% CI 0.62–0.90; P=0.002).

Conclusion

Targeted therapy, when associated with conventional CT, demonstrated gains in the PFS of patients with TNBC.

Adjuvant high-dose chemotherapy with autologous hematopoietic stem cell support for high-risk primary breast cancer: results from the Italian national registry

The efficacy of high-dose chemotherapy (HDC) and autologous hemopoietic progenitor cell transplantation (AHPCT) for breast cancer (BC) patients has been an area of intense controversy among the medical oncology community. The aim of this study was to assess toxicity and efficacy of this procedure in a large cohort of high-risk primary BC patients who underwent AHPCT in Italy. A total of 1183 patients receiving HDC for high-risk BC (HRBC) (>3 positive nodes) were identified in the Italian registry. The median age was 46 years, 62% of patients were premenopausal at treatment, 60.1% had endocrine-responsive tumors, and 20.7% had a human epidermal growth factor receptor 2 (HER2)-positive tumor. The median number of positive lymph nodes (LN) at surgery was 15, with 71.5% of patients having ≥ 10 positive nodes. Seventy-three percent received an alkylating agent-based HDC as a single procedure, whereas 27% received epirubicin or mitoxantrone-containing HDC, usually within a multitransplantation program. The source of stem cells was peripheral blood in the vast majority of patients. Transplantation-related mortality was .8%, whereas late cardiac and secondary tumor-related mortality were around 1%, overall. With a median follow-up of 79 months, median disease-free and overall survival (OS) in the entire population were 101 and 134 months, respectively. Subgroup analysis demonstrated that OS was significantly better in patients with endocrine-responsive tumors and in patients receiving multiple transplantation procedures. HER2 status did not affect survival probability. The size of the primary tumor and number of involved LN negatively affected OS. Adjuvant HDC with AHPCT has a low mortality rate and provides impressive long-term survival rates in patients with high-risk primary BC. Our results suggest that this treatment modality should be proposed in selected HRBC patients and further investigated in clinical trials.

p53-Based cyclotherapy: exploiting the 'guardian of the genome' to protect normal cells from cytotoxic therapy

Side effects of chemotherapy are a major impediment in the treatment of cancer. Cyclotherapy is an emerging therapeutic strategy for protecting normal cells from the side effects of chemotherapy. Low, non-genotoxic doses of known p53 activators can be used to induce p53-dependent cell cycle arrest in normal cells bearing wild-type p53. This cytostatic effect of p53 can protect normal cells from the toxicity of S- or M-phase poisons. Here, we have reviewed existing cyclotherapy regimens using two well-known p53 activators, nutlin-3 and actinomycin D. We have highlighted an exemplar clinical perspective for cyclotherapy in breast cancer. The recent development of novel stapled peptides as activators of p53 without the corresponding cytotoxicity holds great promise for cyclotherapy to enhance the therapeutic window of existing chemotherapy drugs.

Tumor histological subtyping determined by hormone receptors and HER2 status defines different pathological complete response and outcome to dose-dense neoadjuvant chemotherapy in breast cancer patients

PURPOSE

To assess the impact in pathological complete response (pCR) and outcome of two dose-dense neoadjuvant chemotherapy (DDNC) regimens among different histological subtypes determined by hormonal receptor (HR) and HER2 status in breast cancer patients.

METHODS

A total of 127 breast cancer patients were treated with DDNC in two prospective studies. A: adriamycin 40 mg/m(2) on day (d) 1 plus paclitaxel 150 mg/m(2) and gemcitabine 2,000 mg/m(2) on d2 for six cycles (n = 54). B: epirubicin 90 mg/m(2), cyclophosphamide 600 mg/m(2) on d1 for three cycles, followed by paclitaxel 150 mg/m(2) and gemcitabine 2,500 mg/m(2) on d1 ± trastuzumab according to HER2 status (n = 73). Histological subtypes of breast cancer were 49 % HR+/HER2-, 17.5 % HR+/HER2+, 13.5 % HR-/HER2+ and 20 % HR-/HER2-.

RESULTS

pCR (absence of invasive cells in breast and lymph node) was achieved in 35 patients (28 %). The pCR rate was significantly different between histological subtypes: HR+/HER2- (9 %), HR+/HER2+ (23 %), HR-/HER2+ (50 %), HR-/HER2- (56 %) (p < 0.001). The median follow-up was 81 months (r: 15-150 months). HR-/HER2- tumor subtype had a significantly worse DFS compared to HR+/HER2- (p = 0.02), RH+/HER2+ (p = 0.04) and HR-/HER2+ tumor subtypes (p = 0.02). HR-/HER2- tumor subtype had a significantly shorter OS compared to HR+/HER2- (p = 0.007), RH+/HER2+ (p = 0.05), and HR-/HER2+ (p = 0.03) tumor subtypes. However, no significant difference was observed in DFS and OS among HR-/HER2- tumors that achieved a pCR.

CONCLUSIONS

HR-/HER2- and HR-/HER2+ subtypes had a high pCR rate to DDNC. HR-/HER2- tumors had a worse outcome compared to other tumor subtypes but no significant difference was observed among HR-/HER2- tumors that achieved a pCR.

[Triple-negative breast cancer: histoclinical and molecular features, therapeutic management and perspectives]

Triple-negative breast cancer (TNBC), as defined by the absence of estrogen and progesterone receptor expression, as well as the lack of HER2 overexpression/amplification, corresponds to 15% of breast cancer and represents an aggressive form of the disease. TNBC are frequently confounded with basal subtype in the molecular classification of breast cancer and also share some similarities with BRCA1-mutated tumors. Epidemiological and clinical characteristics are distinct from other subtypes, including a younger age at diagnosis, a higher risk of relapse in spite of increased chemosensitivity, and a higher incidence of lung and brain metastatic relapses. Conventional cytotoxics remain the mainstay of current systemic management but recent evaluation of more targeted therapeutics, including specific cytotoxics (such as the use of platinum salts), PARP and EGFR inhibition, and antiangiogenics have been performed, providing contrasted but rather disappointing results. Recent data indicate that TNBC represent a heterogeneous entity composed of multiple and distinct molecular subtypes, which should deserve specific targeted therapeutics.

Mobilization of Peripheral Blood Stem Cells Using Regimen Combining Docetaxel with Granulocyte Colony-stimulating Factor in Breast Cancer Patients

OBJECTIVE

To evaluate the effectiveness and safety of the mobilization of peripheral blood hematopoietic stem cells by combining docetaxel with granulocyte colony-stimulating factor (G-CSF) in breast cancer patients.

METHODS

A total of 57 breast cancer patients were treated with docetaxel 120 mg/m(2). When the white blood cell (WBC) count decreased to 1.0×10(9)/L, patients were given G-CSF 5 μg/kg daily by subcutaneous injection until the end of apheresis. Peripheral blood mononuclear cells (MNC) were isolated by Cobe Spectra Apheresis System. The percentage of CD34(+) cell was assayed by flow cytometry.

RESULTS

At a median 6 of days (range 3-8) after the administration of docetaxel, the median WBC count decreased to 1.08×10(9)/L (range 0.20-2.31). The median duration of G-CSF mobilization was 3 days (range 2-7). The MNC collection was conducted 8-12 days (median 10 days) after docetaxel treatment. The median MNC was 5.35×10(8)/kg (range 0.59-14.07), the median CD34(+) cell count was 2.43×10(6)/kg (range 0.16-16.69). The CD34(+) cell count was higher than 1.00×10(6)/kg in 47 of 57 cases (82.46%) and higher than 2.00×10(6)/kg in 36 cases (63.16%). The CD34(+) cell count was higher than 2.00×10(6)/kg in 27 collections (23.68%). The MNC count and the CD34(+) cell count were correlated with the bottom of WBC after docetaxel chemotherapy (r=0.364, 0.502, P=0.005, 0.000). The CD34(+) cell count was correlated with the MNC count (r=0.597, P=0.000). The mobilization and apheresis were well tolerated in all patients. Mild perioral numbness and numbness of hand or feet were observed in 3 cases. No serious adverse events were reported.

CONCLUSION

Mobilization of peripheral blood hematopoietic stem cell by combining docetaxel with G-CSF was effective and safety in breast cancer patients.

The role of immunohistochemistry in breast cancer patients treated with neoadjuvant chemotherapy: an old tool with an enduring prognostic value

BACKGROUND

To assess the molecular subtypes determined by hormonal receptors (HR) and human epidermal growth factor receptor 2 (HER2) status and the role of proliferation measured by the Ki-67 marker as predictive and prognostic factors in breast cancer patients treated with neoadjuvant chemotherapy.

METHODS

A total of 127 breast cancer patients were treated with neoadjuvant chemotherapy every 2 weeks as part of 2 studies. Study A consisted of the administration of Adriamycin (40 mg/m(2)) on day 1 plus paclitaxel (150 mg/m(2)) and gemcitabine 2000 mg/m(2)) on day 2 for 6 cycles (n = 54). Study B consisted of the administration of epirubicin (90 mg/m(2)), cyclophosphamide (600 mg/m(2)) on day 1 for 3 cycles, followed by the administration of paclitaxel (150 mg/m(2)) and gemcitabine 2500 (mg/m(2)) on day 1 with or without trastuzumab according to HER2 status (n = 73). In study A, patients did not receive trastuzumab regardless of HER2 status. The molecular subtypes of the patients with breast cancer were classified as 49% HR(+)/HER2(-), 17.5% HR(+)/HER2(+), 13.5% HR(-)/HER2(+), and 20% HR(-)/HER2(-).

RESULTS

Pathologic complete response (pCR), defined as the absence of invasive cells in the breast and the lymph nodes, was achieved in 35 (28%) patients. The pCR rate was significantly different between the molecular subtypes of breast cancer, with 9% in HR(+)/HER2(-), 23% in HR(+)/HER2(+), 50% in HR(-)/HER2(+), and 56% in HR(-)/HER2(-) tumors (P < .001). The pCR rate was significantly higher in tumors that had high Ki-67 (≥20%) expression and were HR(-). HER2(+) was associated with a higher trend of pCR but did not reach statistical significance. The median follow-up was 81 months (r = 15-150 months). Patients who achieved a pCR had a significantly lower recurrence (P = .01) and higher overall survival (P = .02) compared with those who did not achieve pCR. A multivariate analysis revealed that pCR (hazard ratio 0.24 [95% CI, 0.07-0.7]; P = .019), the molecular subtype (hazard ratio 0.3 [95% CI, 0.1-0.8]; P = .02), and the Ki-67 index (hazard ratio 3.2 [95% CI, 1.4-7.1]; P = .004) were significant independent predictors of disease-free survival. Similar results were obtained for overall survival, in which the pCR rate (hazard ratio 0.119 [95% CI, 0.028-0.5]; P = .004), the molecular subtype (hazard ratio 0.17 [95% CI, 0.03-0.86]; P = .02), and the Ki-67 index (hazard ratio 3.6 [95% CI, 1.3-9.7]; P = .01) also displayed a significant influence on survival.

CONCLUSIONS

Molecular subtypes and Ki-67 index were independent prognostic factors for disease-free survival and overall survival in breast cancer patients treated with neoadjuvant chemotherapy. A high rate of Ki-67 and HR(-) expression were predictors of pCR.

Triple-negative breast cancer: multipronged approach, single-arm pilot phase II study

Anthracyclines (A) and taxanes (T) are standard first-line chemotherapy agents for patients with advanced breast cancer. Platinum analogues have also shown activity in the triple-negative breast cancer (TNBC) histology, but clinical data are limited. Here we report the long-term follow-up of a phase II study on TNBC treated with a combined modality therapy, including induction with AT, cyclophosphamide, methotrexate, and 5-fluorouracil (CMF) with concurrent radiation therapy, and a dose-dense consolidation chemotherapy (HDCT) with carboplatin (CBDCA), ifosfamide (IFX), etoposide (VP-16). Patients' median age was 44 years, with 73% premenopausal. Epirubicin 75 mg/m(2) and docetaxel 75 mg/m(2) were administered to 70 patients with TNBC: as neoadjuvant and adjuvant therapy to 12 and 58 patients, respectively. Postoperative radiation therapy, 5000 cGy, was delivered, synchronous with triweekly CMF. After radiation therapy, two courses of HDCT with CBDCA, IFX, VP-16, were given, with hematological growth factors. After a median follow-up of 81 months, all patients were evaluable for toxicity and response. Most important toxicity were grade 3 skin reaction and grade 4 hematological in 3% and 31% of patients, respectively. Pathological complete response was observed in 25% of patients receiving preoperative chemotherapy. Treatment failures were as follows: eight visceral, four contralateral breast cancer, four locoregional, and one leukemia. Five-year progression-free survival and overall survival rate were 78% and 91%, respectively. Induction chemotherapy, followed by chemoradiation therapy and HDCT, provides a prolonged disease-free period and a significant increase in overall survival in TNBC, with an acceptable toxicity profile.

Pathologic response to short intensified taxane-free neoadjuvant chemotherapy in patients with highly proliferative operable breast cancer

OBJECTIVES

Breast cancer treatment relies on 3 major phenotypical subtypes, including the triple-negative (TN), HER2-positive, and hormone receptor-positive (estrogen receptor/progesterone receptor) ones. We retrospectively determined the clinical and pathologic response rates to intensified taxane-free neoadjuvant chemotherapy according to these phenotypical classes in a series of patients with highly proliferative operable breast cancer, and examined the patterns of recurrence.

METHODS

Patients with early breast cancer with highly proliferative (S-phase fraction >4%) operable tumors of >3 cm received 4 cycles of intensified neoadjuvant chemotherapy with high-dose cyclophosphamide (doxorubicin 70 mg/m d1, cyclophosphamide 700 mg/m d1/d8, and 5 FU 700 mg/m d1-d5) every 3 weeks.

RESULTS

Fifty-five patients were included in the analysis. Patients with TN phenotype experienced a high pathologic complete response (pCR) rate to intensified chemotherapy in comparison with patients with HER2-positive and estrogen receptor/progesterone receptor tumors (47%, 0%, and 12%, respectively). Forty percent of patients with TN breast cancer recurred after a median follow-up of nearly 11 years, but only 22% of those achieving a pCR.

CONCLUSIONS

A high pCR rate to short intensified neoadjuvant chemotherapy with high-dose cyclophosphamide was achieved in patients with operable highly proliferative TN breast cancer, and pCR was associated with a low rate of recurrence.