Clinical outcomes after 1 versus 2-3 lines of neoadjuvant therapy in stage III inflammatory breast cancer.

PURPOSE: Many stage III inflammatory breast cancer (IBC) patients experience a sufficient response to first-line (1L) neoadjuvant chemotherapy (NAC) to allow surgery, while some require additional NAC. We evaluated the pathologic complete response (pCR), breast cancer-free survival (BCFS) and overall survival (OS) among patients requiring 1 vs. 2-3 lines (L) of NAC prior to surgery. METHODS: Stage III IBC patients from 2 institutions who received 1L or 2-3L of NAC prior to surgery were identified. Hormone receptor and HER2 status, grade, and pCR were evaluated. BCFS and OS were evaluated by the Kaplan-Meier method. Multivariable Cox models were utilized to estimate the hazard ratio (HR). RESULTS: 808 eligible patients (1997-2020) were identified (median age 51 years, median follow-up 69 months). 733 (91%) had 1L and 75 (9%) had 2-3L of NAC. Grade III, triple-negative and HER2-positive disease were more prevalent in 2-3L patients. 178 (24%) 1L and 14 (19%) 2-3L patients had pCR. 376 1L patients and 41 2-3L patients had recurrences. The 5-year BCFS was worse for the 2-3L group (33 vs. 46%, HR = 1.37; 95% CI 0.99-1.91). However, in 192 patients with a pCR, BCFS was similar (76 vs. 83% in 1L vs. 2-3L, respectively). There were 308 deaths (276 among 1L and 32 among 2-3L patients). The 5-year OS in 1L vs. 2-3L was 60 vs. 53% (HR = 1.32, 95% CI 0.91-1.93). CONCLUSIONS: Among stage III IBC patients, pCR rates were similar, irrespective of the NAC lines number, and BCFS and OS were comparable with pCR after 1L and 2-3L.

Body composition and breast cancer risk and treatment: mechanisms and impact.

PURPOSE: The purpose of this review is to clarify the association of body composition with breast cancer risk and treatment, including physiological mechanisms, and to elucidate strategies for overcoming unfavorable body composition changes that relate to breast cancer progression. METHODS: We have summarized updated knowledge regarding the mechanism of the negative association of altered body composition with breast cancer risk and treatment. We also review strategies for reversing unfavorable body composition based on the latest clinical trial results. RESULTS: Body composition changes in patients with breast cancer typically occur during menopause or as a result of chemotherapy or endocrine therapy. Dysfunction of visceral adipose tissue (VAT) in the setting of obesity underlies insulin resistance and chronic inflammation, which can lead to breast cancer development and progression. Insulin resistance and chronic inflammation are also observed in patients with breast cancer who have sarcopenia or sarcopenic obesity. Nutritional support and a personalized exercise program are the fundamental interventions for reversing unfavorable body composition. Other interventions that have been explored in specific situations include metformin, testosterone, emerging agents that directly target the adipocyte microenvironment, and bariatric surgery. CONCLUSIONS: A better understanding of the biology of body composition phenotypes is key to determining the best intervention program for patients with breast cancer.

Quality and quantity of visceral fat tissue are associated with insulin resistance and survival outcomes after chemotherapy in patients with breast cancer.

PURPOSE: Recent studies suggest that the quality and quantity of visceral adipose tissue (VAT) play significant roles in adipocyte function, and are related to insulin resistance. We tested the hypothesis that high amounts of upper VAT (aVAT) and low-quality VAT worsen treatment outcomes via altered insulin metabolism. METHODS: Cohort 1 included 106 women with breast cancer who were undergoing surgery. Homeostasis model assessment of insulin resistance (HOMA-R), insulin-like growth factor (IGF)-1, and IGF-binding protein 3 (IGFBP3) were measured before the initiation of treatment. aVAT was measured via computed tomography (CT). VAT quality was assessed using CT-determined Hounsfield units (VAT-HU). Associations between the variables investigated and VAT quality and quantity were analyzed. Cohort 2 included 271 patients who underwent chemotherapy. Associations between the variables investigated and survival outcomes after chemotherapy were analyzed via retrospective chart review. RESULTS: In cohort 1, aVAT was significantly correlated with insulin and HOMA-R levels. As body mass index (BMI) class increased, mean IGF-1 increased and mean IGFBP3 decreased, but these trends were not statistically significant. In cohort 2, aVAT was significantly positively correlated with BMI. The patients in the third aVAT tertiles had significantly shorter distant disease-free survival (dDFS) after neoadjuvant chemotherapy setting. In multivariate analysis, aVAT and VAT-HU were significantly associated with shorter dDFS. CONCLUSIONS: High aVAT and low-quality VAT were associated with poor survival outcome, increased insulin levels, and insulin resistance. The present study suggests the importance of evaluating the quality and quantity of VAT when estimating insulin resistance and treatment outcomes.

The efficacy of first-line chemotherapy in endocrine-resistant hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer.

PURPOSE: Combinations of endocrine therapy (ET) and targeted therapy (CDK4/6 or mTOR inhibitors) are standard of care for HR+/HER2- metastatic breast cancer (MBC). When ET is not effective, chemotherapy is commonly used. However, clinical outcomes of chemotherapy in the endocrine-resistant setting are limited. The purpose of this study was to identify predictive factors and the compare efficacies of chemotherapy agents in endocrine-resistant MBC. METHODS: We conducted a retrospective study of patients with HR+/HER2- MBC who received chemotherapy after progression on ET with or without targeted therapy at MD Anderson Cancer Center from 1999 to 2017. We collected baseline clinicopathological and all treatment data. Primary endpoint was time to treatment failure (TTF) of first-line chemotherapy for MBC. RESULTS: For the 1258 patients analyzed, mean age was 55.3 years (range 21-91). Previous treatment with targeted therapy was recorded for 390 patients (31%): 264 with CDK4/6 inhibitor, 205 with mTOR inhibitor, and 79 treated with both. The most frequent chemotherapy agents were capecitabine (48.9%) and taxanes (28.6%). After adjustment for all factors in a multivariate model, previous treatment with a CDK4/6 inhibitor had the strongest negative effect on TTF regardless of ET duration (hazard ratio [HR] 1.84; 95%CI 1.49-2.27; p < 0.001). Conversely, capecitabine had significantly longer median TTF than taxanes regardless of whether patients had prior exposure to taxanes in primary setting (6.1 vs 4.9 months; HR 0.64; 95%CI 0.55-0.75; p < 0.001). CONCLUSIONS: Previous exposure to CDK4/6 inhibitor had a negative predictive effect for the efficacy of chemotherapy. Capecitabine had the best efficacy against endocrine-resistant breast cancer.

Quantitative hormone receptor (HR) expression and gene expression analysis in HR+ inflammatory breast cancer (IBC) vs non-IBC.

BACKGROUND: The purpose of this study was to determine the prognostic role of hormone receptor (HR) on inflammatory breast cancer (IBC) to elucidate its aggressive biological behavior. METHODS: We evaluated the expression of estrogen receptor (ER) and progesterone receptor (PR) by immunohistochemical staining and determined the predictive and prognostic role of HR expression on 189 patients with HR+/HER2- IBC and 677 patients with HR+/HER2- stage III non-IBC. Furthermore, we performed gene expression (GE) analyses on 137 patients with HR+/HER2- IBC and 252 patients with HR+/HER2- non-IBC to detect genes that are specifically overexpressed in IBC. RESULTS: The expression of ER% was significantly associated with longer distant disease-free survival and overall survival. However, there was no significant relationship between ER% and neoadjuvant chemotherapy outcome. In the GE study, 84 genes were identified as significantly distinguishing HR+ IBC from non-IBC. Among the top 15 canonical pathways expressed in IBC, the ERK/MAPK, PDGF, insulin receptor, and IL-7 signaling pathways were associated with the ER signaling pathway. Upregulation of the MYC gene was observed in three of these four pathways. Furthermore, HR+/HER2- IBC had significantly higher MYC amplification, and the genetic alteration was associated with poor survival outcome. CONCLUSIONS: Higher ER expression was significantly associated with improved survival in both HR+/HER2- IBC and HR+/HER2- stage III non-IBC patients. HR+/HER2- IBC had several activated pathways with MYC upregulation, and the genetic alteration was associated with poor survival outcome. The results indicate that MYC may be a key gene for understanding the biology of HR+/HER2- IBC.

A phase Ib study of entinostat plus lapatinib with or without trastuzumab in patients with HER2-positive metastatic breast cancer that progressed during trastuzumab treatment.

BACKGROUND: Human epidermal growth factor 2 (HER2) is an effective therapeutic target in breast cancer; however, resistance to anti-HER2 agents such as trastuzumab and lapatinib develops. In a preclinical model, an HDAC inhibitor epigenetically reversed the resistance of cancer cells to trastuzumab and showed synergistic efficacy with lapatinib in inhibiting growth of trastuzumab-resistant HER2-positive (HER2+) breast cancer. METHODS: A phase 1b, dose escalation study was performed to assess maximum tolerated dose, safety/toxicity, clinical efficacy and explored pharmacodynamic biomarkers of response to entinostat combined with lapatinib with or without trastuzumab. RESULTS: The combination was safe. The MTD was lapatinib, 1000 mg daily; entinostat, 12 mg every other week; trastuzumab, 8 mg/kg followed by 6 mg/kg every 3 weeks. Adverse events included diarrhoea (89%), neutropenia (31%), and thrombocytopenia (23%). Neutropenia, thrombocytopenia and hypokalaemia were noted. Pharmacodynamic assessment did not yield conclusive results. Among 35 patients with evaluable response, PR was observed in 3 patients and CR in 3 patients, 1 maintained SD for over 6 months. DISCUSSION: This study identified the MTD of the entinostat, lapatinib, and trastuzumab combination that provided acceptable tolerability and anti-tumour activity in heavily pre-treated patients with HER2+ metastatic breast cancer, supporting a confirmatory trial.

Impact of change in body mass index during neoadjuvant chemotherapy and survival among breast cancer subtypes.

PURPOSE: We hypothesized that an increase in BMI category during neoadjuvant chemotherapy (NAC) would be associated with pathological complete response (pCR) rate and worse survival outcomes in primary breast cancer patients. METHODS: We reviewed the records of 4029 patients with stage I-III breast cancer who had undergone NAC and definitive surgery at our institution between May 1, 1990 and April 30, 2013. BMI values at baseline and after NAC were recorded, and the corresponding BMI category was assessed with the WHO classification. Overall survival (OS) and recurrence-free survival (RFS) were estimated using the Kaplan-Meier method, and multivariate Cox regression models were used to estimate the effect of covariates of interest on OS and RFS. RESULTS: The median follow-up period was 3.95 years. A change in BMI category from normal to obese during NAC was independently associated with shorter OS duration than was maintaining a normal weight [hazard ratio (HR) 1.637; 95%CI 1.066-2.514; p = 0.0242]. Kaplan-Meier curves among breast cancer subtypes showed differences, and a decrease in BMI led to better RFS and OS rates in obese patients with HR+/HER2- disease; those who maintained BMI also showed better prognosis for triple-negative breast cancer (TNBC). We saw no association between BMI change and pCR rate. CONCLUSION: Our data suggest that inability to maintain normal weight during NAC is a predictive marker of poor survival but not pCR. It may be important for patients to maintain a normal weight during NAC.

[Breast-Conserving Surgery Using Real-Time Virtual Sonography in a Breast Cancer Patient Who Received Neoadjuvant Chemotherapy - ACase Report].

We report a case of breast-conserving surgeryusing real-time virtual sonography(RVS)in a breast cancer patient who received neoadjuvant chemotherapy(NAC). The patient was a 63-year-old woman. Ultrasound(US)showed a lobulated 45 ×40×40mm diameter mass in the C area of the right breast. Histological examination found invasive ductal carcinoma that was negative for estrogen and progesterone receptors and for human epidermal growth factor receptor type 2/neu protein expression, and the Ki-67 index was 50%. The patient was diagnosed with breast cancer clinical stage II A(T2N0M0). The basal-like subtype is more sensitive to anthracycline-based NAC than luminal breast cancers. The patient wanted breastconserving surgery. Therefore, we treated the patient with NAC. First, we obtained US volume data of the tumor as a Digital Imaging and Communication in Medicine(DICOM)file, simplyscanning the skin over the lesion gentlywith the probe. We administered tri-weeklynanoparticle albumin-bound paclitaxel(nab PTX)followed bya fluorouracil, epirubicin, and cyclophosphamide( FEC)regimen. Follow-up computed tomography(CT)and US showed good tumor concentric shrinkage without anysurrounding lesion after NAC. Finally, right breast-conserving surgerywas performed, using RVS to detect the area where the tumor was before NAC in the US image after NAC. Histopathologically, the effect of the chemotherapy was Grade 2a and the surgical margins were negative.

[The Case of a Patient with Invasive Lobular Carcinoma with Solitary Metastasis in Pectoralis Major Muscle].

A 44 -year-old woman presented at the outpatient department with a chief complaint of swelling in the right breast. MRI showed a huge breast tumor accompanied by solitary enhanced masses in the pectoralis major muscle. After receiving neoadjuvant chemotherapy, she underwent mastectomy (Halsted operation) and axillary dissection. Pathological examination revealed an E-cadherin-positive infiltrating lobular carcinoma (ILC), and the absence of residual tumor in the muscle was confirmed. In cases of solitary metastasis in the muscle, treatment selection is sometimes difficult. Further research is needed to determine whether surgery contributes to local control in cases of advanced ILC with muscle metastasis.

[Long-Term Outcome of Radiofrequency Ablation Therapy for Breast Cancer].

Although radiofrequency ablation (RFA) is promising for the local treatment of breast cancer, data concerning the longterm results are limited. The present study attempted to evaluate the safety and efficacy of RFA and to clarify patient outcomes after treatment. The study included 26 breast cancer patients treated with RFA between 2006 and 2010. There were no acute complications such as burns. All subjects were followed-up after breast radiation and systemic therapies. At the median follow-up period of 88 months, no local recurrence or distant metastases had occurred. After treatment, a hard lump was formed around the ablated area, which gradually decreased in size in all cases (p<0.001). The lumps were calcified in 9 cases. Nipple retraction persisted in 2 cases. However, it is necessary to recognize that a cosmetic result of RFA was not excellent in all cases, RFA appears to be a safe local treatment technique for breast cancer patients.

Maintenance Pembrolizumab Therapy in Patients with Metastatic HER2-negative Breast Cancer with Prior Response to Chemotherapy.

PURPOSE: Accumulating toxicities hinder indefinite chemotherapy for many patients with metastatic/recurrent HER2-negative breast cancer. We conducted a phase II trial of pembrolizumab monotherapy following induction chemotherapy to determine the efficacy of maintenance immunotherapy in patients with metastatic HER2-negative inflammatory breast cancer (IBC) and non-IBC triple-negative breast cancer (TNBC) and a biomarker study. PATIENTS AND METHODS: Patients with a complete response, partial response, or stable disease (SD) after at least three cycles of chemotherapy for HER2-negative breast cancer received pembrolizumab, regardless of programmed death-ligand 1 expression. Pembrolizumab (200 mg) was administered every 3 weeks until disease progression, intolerable toxicity, or 2 years of pembrolizumab exposure. The endpoints included the 4-month disease control rate (DCR), progression-free survival (PFS), overall survival, and response biomarkers in the blood. RESULTS: Of 43 treated patients, 11 had metastatic IBC and 32 non-IBC TNBC. The 4-month DCR was 58.1% [95% confidence interval (CI), 43.4-72.9]. For all patients, the median PFS was 4.8 months (95% CI, 3.0-7.1 months). The toxicity profile was similar to the previous pembrolizumab monotherapy study. Patients with high T-cell clonality at baseline had a longer PFS with pembrolizumab treatment than did those with low T-cell clonality (10.4 vs. 3.6 months, P = 0.04). Patients who achieved SD also demonstrated a significant increase in T-cell clonality during therapy compared with those who did not achieve SD (20% vs. 5.9% mean increase, respectively; P = 0.04). CONCLUSIONS: Pembrolizumab monotherapy achieved durable treatment responses. Patients with a high baseline T-cell clonality had prolonged disease control with pembrolizumab.

Reassessing Estrogen Receptor Expression Thresholds for Breast Cancer Prognosis in HER2-negative Patients Using Shape Restricted Modeling.

Purpose: To assess the dynamic link between continuous estrogen receptor (ER) expression and long-term clinical outcomes in non-metastatic breast cancer and to identify the ideal cutoff value for ER expression to optimize endocrine therapy use. Methods: The study included 3055 female patients with stage II or III HER2-negative breast cancer. The primary outcomes were time to recurrence or death (TTR) and overall survival (OS). We used a novel shape-restricted Cox model to determine the desirable ER expression cutoff to predict breast cancer prognoses. Our novel model allows ER as a continuous variable, utilizing a flexible monotone-shaped Cox regression to assess its association with survival outcomes holistically. Results: The shape-restricted Cox model identified 10% ER as the preferred cutoff to predict TTR. The finding was confirmed by the log-rank test and standard Cox model that patients with ER ≥ 10% had TTR benefit over ER < 10% (log-rank p < 0.001). No OS or TTR benefit of adjuvant endocrine therapy was observed in patients with 1% ≤ ER < 10% (HR 0.877, 95% CI 0.481-1.600, p = 0.668 for TTR and HR 0.698, 95% CI 0.337-1.446, p = 0.333 for OS). Conclusions: Using the shape-restricted Cox model, this study suggests a potential preferred threshold of 10% for predicting TTR. The findings could assist physicians in effectively weighing the benefits and risks of adjuvant endocrine therapy for patients with ER < 10% disease, particularly in cases involving severe adverse events. Further prospective studies are warranted to validate the recommended cutoff value.

Inflammatory breast cancer biomarker identification by simultaneous TGIRT-seq profiling of coding and non-coding RNAs in tumors and blood.

Inflammatory breast cancer (IBC) is the most aggressive and lethal breast cancer subtype, but lags in biomarker identification. Here, we used an improved Thermostable Group II Intron Reverse Transcriptase RNA sequencing (TGIRT-seq) method to simultaneously profile coding and non-coding RNAs from tumors, PBMCs, and plasma of IBC and non-IBC patients and healthy donors. Besides RNAs from known IBC-relevant genes, we identified hundreds of other overexpressed coding and non-coding RNAs (p≤0.001) in IBC tumors and PBMCs, including higher proportions with elevated intron-exon depth ratios (IDRs), likely reflecting enhanced transcription resulting in accumulation of intronic RNAs. As a consequence, differentially represented protein-coding gene RNAs in IBC plasma were largely intron RNA fragments, whereas those in healthy donor and non-IBC plasma were largely fragmented mRNAs. Potential IBC biomarkers in plasma included T-cell receptor pre-mRNA fragments traced to IBC tumors and PBMCs; intron RNA fragments correlated with high IDR genes; and LINE-1 and other retroelement RNAs that we found globally up-regulated in IBC and preferentially enriched in plasma. Our findings provide new insights into IBC and demonstrate advantages of broadly analyzing transcriptomes for biomarker identification. The RNA-seq and data analysis methods developed for this study may be broadly applicable to other diseases.

Identification of Kinase Targets for Enhancing the Antitumor Activity of Eribulin in Triple-Negative Breast Cell Lines.

BACKGROUND: Triple-negative breast cancer (TNBC) is the most aggressive molecular subtype of breast cancer, and current treatments are only partially effective in disease control. More effective combination approaches are needed to improve the survival of TNBC patients. Eribulin mesylate, a non-taxane microtubule dynamics inhibitor, is approved by the U.S. Food and Drug Administration to treat metastatic breast cancer after at least two previous chemotherapeutic regimens. However, eribulin as a single agent has limited therapeutic efficacy against TNBC. METHODS: High-throughput kinome library RNAi screening, Ingenuity Pathway Analysis, and STRING analysis were performed to identify target kinases for combination with eribulin. The identified combinations were validated using in vivo and ex vivo proliferation assays. RESULTS: We identified 135 potential kinase targets whose inhibition enhanced the antiproliferation effect of eribulin in TNBC cells, with the PI3K/Akt/mTOR and the MAPK/JNK pathways emerging as the top candidates. Indeed, copanlisib (pan-class I PI3K inhibitor), everolimus (mTOR inhibitor), trametinib (MEK inhibitor), and JNK-IN-8 (pan-JNK inhibitor) produced strong synergistic antiproliferative effects when combined with eribulin, and the PI3K and mTOR inhibitors had the most potent effects in vitro. CONCLUSIONS: Our data suggest a new strategy of combining eribulin with PI3K or mTOR inhibitors to treat TNBC.

Emerging drug targets for triple-negative breast cancer: a guided tour of the preclinical landscape.

INTRODUCTION: Triple-negative breast cancer (TNBC) is the most fatal molecular subtype of breast cancer because of its aggressiveness and resistance to chemotherapy. FDA-approved therapies for TNBC are limited to poly(ADP-ribose) polymerase inhibitors, immune checkpoint inhibitors, and trophoblast cell surface antigen 2-targeted antibody-drug conjugate. Therefore, developing a novel effective targeted therapy for TNBC is an urgent unmet need. AREAS COVERED: In this narrative review, we discuss emerging targets for TNBC treatment discovered in early translational studies. We focus on cancer cell membrane molecules, hyperactive intracellular signaling pathways, and the tumor microenvironment (TME) based on their druggability, therapeutic potency, specificity to TNBC, and application in immunotherapy. EXPERT OPINION: The significant challenges in the identification and validation of TNBC-associated targets are 1) application of appropriate genetic, molecular, and immunological approaches for modulating the target, 2) establishment of a proper mouse model that accurately represents the human immune TME, 3) TNBC molecular heterogeneity, and 4) failure translation of preclinical findings to clinical practice. To overcome those difficulties, future research needs to apply novel technology, such as single-cell RNA sequencing, thermostable group II intron reverse transcriptase sequencing, and humanized mouse models. Further, combination treatment targeting multiple pathways in both the TNBC tumor and its TME is essential for effective disease control.

EGFR is a master switch between immunosuppressive and immunoactive tumor microenvironment in inflammatory breast cancer.

Inflammatory breast cancer (IBC), the most aggressive breast cancer subtype, is driven by an immunosuppressive tumor microenvironment (TME). Current treatments for IBC have limited efficacy. In a clinical trial (NCT01036087), an anti-EGFR antibody combined with neoadjuvant chemotherapy produced the highest pathological complete response rate ever reported in patients with IBC having triple-negative receptor status. We determined the molecular and immunological mechanisms behind this superior clinical outcome. Using novel humanized IBC mouse models, we discovered that EGFR-targeted therapy remodels the IBC TME by increasing cytotoxic T cells and reducing immunosuppressive regulatory T cells and M2 macrophages. These changes were due to diminishing immunosuppressive chemokine expression regulated by transcription factor EGR1. We also showed that induction of an immunoactive IBC TME by an anti-EGFR antibody improved the antitumor efficacy of an anti-PD-L1 antibody. Our findings lay the foundation for clinical trials evaluating EGFR-targeted therapy combined with immune checkpoint inhibitors in patients with cancer.

Changes in Overall Survival over Time for Patients with de novo Metastatic Breast Cancer.

The purpose of this study was to determine the change in overall survival (OS) for patients with de novo metastatic breast cancer (dnMBC) over time. We conducted a retrospective cohort study with 1981 patients with dnMBC diagnosed between January 1995 and December 2017 at The University of Texas MD Anderson Cancer Center. OS was measured from the date of diagnosis of dnMBC. OS was compared between patients diagnosed during different time periods: 5-year periods and periods defined according to when key agents were approved for clinical use. The median OS was 3.4 years. The 5- and 10-year OS rates improved over time across both types of time periods. A subgroup analysis showed that OS improved significantly over time for the estrogen-receptor-positive/HER2-positive (ER+/HER2+) subtype and exhibited a tendency toward improvement over time for the ER-negative (ER-)/HER2+ subtype. In addition, median OS was significantly longer in patients with non-inflammatory breast cancer (p = 0.02) and patients with ER+ disease, progesterone-receptor-positive disease, HER2+ disease, lower nuclear grade, locoregional therapy, and metastasis to a single organ (all p < 0.0001). These findings showed that OS at 5 and 10 years after diagnosis in patients with dnMBC improved over time. The significant improvements in OS over time for the ER+/HER2+ subtype and the tendency toward improvement for the ER-/HER2+ subtype suggest the contribution of HER2-targeted therapy to survival.

Pathological complete response of adding targeted therapy to neoadjuvant chemotherapy for inflammatory breast cancer: A systematic review.

BACKGROUND: The current use of targeted therapy plus neoadjuvant chemotherapy for inflammatory breast cancer (IBC) is based on data extrapolated from studies in non-IBC. We conducted a systematic review to determine whether neoadjuvant chemotherapy plus targeted therapy results in a higher pathologic complete response (pCR) rate than neoadjuvant chemotherapy alone in patients with IBC. METHOD AND FINDINGS: This systematic review was registered in the PROSPERO register with registration number CRD42018089465. We searched MEDLINE & PubMed, EMBASE, and EBSCO from December 1998 through July 2020. All English-language clinical studies, both randomized and non-randomized, that evaluated neoadjuvant systemic treatment with or without targeted therapy before definitive surgery and reported the pCR results of IBC patients. First reviewer extracted data and assessed the risk of bias using the Risk of Bias In Non-randomized Studies of Interventions tool. Second reviewer confirmed the accuracy. Studies were divided into 3 groups according to systemic treatment: chemotherapy with targeted therapy, chemotherapy alone, and high-dose chemotherapy with hematopoietic stem cell support (HSCS). Of 995 screened studies, 23 with 1,269 IBC patients met the inclusion criteria. For each of the 3 groups of studies, we computed a weighted average of the pCR rates across all studies with confidence interval (CI). The weighted averages (95% CIs) were as follows: chemotherapy with targeted therapy, 31.6% (26.4%-37.3%), chemotherapy alone, 13.0% (10.3%-16.2%), and high-dose chemotherapy with HSCS, 23.0% (18.7%-27.7%). The high pCR by targeted therapy group came from anti-HER2 therapy, 54.4% (44.3%-64.0%). Key limitations of this study included no randomized clinical studies that included only IBC patients. CONCLUSION: Neoadjuvant chemotherapy plus targeted therapy is more effective than neoadjuvant chemotherapy alone for IBC patients. These findings support current IBC standard practice in particular the use of anti-HER2 targeted therapy.

PI3K and MAPK Pathways as Targets for Combination with the Pan-HER Irreversible Inhibitor Neratinib in HER2-Positive Breast Cancer and TNBC by Kinome RNAi Screening.

Human epidermal growth factor receptor (EGFR) 2 (HER2) is overexpressed/amplified in about 25% of all breast cancers, and EGFR is overexpressed in up to 76% and amplified in up to 24% of triple-negative breast cancers (TNBC). Here, we aimed to identify inhibitors that may enhance the anti-tumor activity of neratinib for HER2+ breast cancer and TNBC. By conducting a non-biased high-throughput RNA interference screening, we identified PI3K/AKT/mTOR and MAPK as two potential inhibitory synergistic canonical pathways. We confirmed that everolimus (mTOR inhibitor) and trametinib (MEK inhibitor) enhances combinatorial anti-proliferative effects with neratinib under anchorage-independent growth conditions (p < 0.05). Compared to single agent neratinib, the combination therapies significantly enhanced tumor growth inhibition in both SUM190 HER2+ breast cancer (neratinib plus everolimus, 77%; neratinib plus trametinib, 77%; p < 0.0001) and SUM149 TNBC (neratinib plus everolimus, 71%; neratinib plus trametinib, 81%; p < 0.0001) xenograft models. Compared to single-agent neratinib, everolimus, or trametinib, both everolimus plus neratinib and trametinib plus neratinib significantly suppressed proliferation marker Ki67 and enhanced antitumor efficacy by activating the apoptosis pathway shown by increased Bim and cleaved-PARP expression. Taken together, our data justify new neratinib-based combinations for both HER2+ breast cancer and TNBC.

A Novel Immunomodulatory 27-Gene Signature to Predict Response to Neoadjuvant Immunochemotherapy for Primary Triple-Negative Breast Cancer.

A precise predictive biomarker for TNBC response to immunochemotherapy is urgently needed. We previously established a 27-gene IO signature for TNBC derived from a previously established 101-gene model for classifying TNBC. Here we report a pilot study to assess the performance of a 27-gene IO signature in predicting the pCR of TNBC to preoperative immunochemotherapy. We obtained RNA sequencing data from the primary tumors of 55 patients with TNBC, who received neoadjuvant immunochemotherapy with the PD-L1 blocker durvalumab. We determined the power and accuracy in predicting pCR for the immunomodulatory (IM) subtype identified by the 101-gene model, the 27-gene IO signature, and PD-L1 expression by immunohistochemistry (IHC). The pCR rate was 45% (25/55). The odds ratios for pCR were as follows: IM subtype by 101-gene model, 3.14 (p = 0.054); 27-gene IO signature, 4.13 (p = 0.012); PD-L1 expression by IHC, 2.63 (p = 0.106); 27-gene IO signature in combination with PD-L1 expression by IHC, 6.53 (p = 0.003). The 27-gene IO signature has the potential to predict the pCR of primary TNBC to neoadjuvant immunochemotherapy. Further analysis in a large cohort is needed.