Early MRI-Derived Volumetric Thresholds Predict Response and Guide Personalization in HER2-Positive Breast Cancer: A Retrospective Study

Trastuzumab beyond progression: a challenge to translational oncology?

Targeting the human epidermal growth factor receptor (HER) family of tyrosine kinase receptors has proven to be effective as a therapeutic strategy for HER type 2 (HER2)-positive breast cancer. Since resistance to trastuzumab occurs relatively frequently, particularly in the metastatic setting, novel anti-HER2 targeted therapies with complementary and/or synergistic mechanisms of action have been under development. Pertuzumab, a HER2-targeted monoclonal antibody that prevents HER2 dimerisation, is the first of a class of promising targeted agents for the treatment of HER2-positive breast cancer. A review of the biomedical literature published prior to February 2013 was conducted in English using PubMed. ClinicalTrials.gov was searched for appropriate clinical trials. The search terms used included breast neoplasm, pertuzumab, dimerisation, and HER2-positive. Abstracts of studies presented at the ASCO and ESMO Annual Meetings, and San Antonio Breast Cancer Symposium were also included. Pertuzumab represents a novel anti-HER2 targeted therapy for HER2-positive breast cancers. In this article, we describe the mechanism of action of pertuzumab, as well as its drug development process and preclinical testing results. Based on the results of ancillary studies, dual inhibition using pertuzumab and trastuzumab was shown to be effective for the management of HER2-positive metastatic breast cancers pre-treated with trastuzumab-based therapy. For the first-line setting, the combination of both pertuzumab and trastuzumab with docetaxel (CLEOPATRA trial; clinical evaluation of pertuzumab and trastuzumab) has changed the paradigm of patient management. Pertuzumab provided a more comprehensive inhibition of HER2-driven signalling pathways. When administered together with trastuzumab, pertuzumab represent a significant advancement for the treatment of HER2-positive metastatic breast cancer patients.

Approximately 20%-30% of metastatic breast cancers show increased expression of the human epidermal growth factor receptor-2 (HER2) tyrosine kinase. Two HER2-specific therapies are currently approved for clinical treatment of patients with HER2-overexpressing metastatic breast cancer. Trastuzumab is a monoclonal antibody against HER2 and is approved for first-line treatment of HER2-positive metastatic breast cancer. Lapatinib is a small molecule dual inhibitor of epidermal growth factor receptor and HER2 tyrosine kinases, and is approved for trastuzumab-refractory disease. Although trastuzumab is a highly effective therapy for patients with HER2-overexpressing metastatic breast cancer, a significant number of patients in the initial clinical trials of trastuzumab monotherapy showed resistance to trastuzumab-based therapy. Further, among those who did respond, the initial trials indicated that the median time to progression was less than 1 year. Similarly, lapatinib is effective in a subset of trastuzumab-refractory cases, but the majority of patients display resistance. This review discusses the multiple molecular mechanisms of resistance that have been proposed in the literature. In addition, novel agents that are being tested for efficacy against HER2-positive breast cancer, including the antibodies pertuzumab and trastuzumab-DM1 and the immunotoxin affitoxin, are reviewed. The introduction of trastuzumab has revolutionized the clinical care of patients with HER2-positive metastatic breast cancer and has resulted in dramatic reductions in recurrences of early-stage HER2-positive breast cancer. The development and implementation of gene- and protein-based assays that measure potential molecular predictors of trastuzumab resistance will allow individualization of HER2-targeted therapeutic approaches, and may ultimately improve treatment of HER2-positive breast cancer.

The introduction of trastuzumab into clinical practice changed the natural course of HER2-positive breast cancer. Currently, treatment with trastuzumab represents the standard of care for HER2-positive breast cancer and this treatment has been approved in the adjuvant, neoadjuvant, and metastatic settings. Besides trastuzumab, two other anti-HER2 agents-lapatinib and pertuzumab-have been approved for the treatment of HER2-positive advanced breast cancer. Strong biologic data support the concept of dual HER2 blockade, with different anti-HER2 agents demonstrating complementary mechanisms of action. Several neoadjuvant and metastatic studies performed in HER2-positive breast cancer using dual HER2 blockade have been proven to outperform anti-HER2 monotherapies. These dual combinations of agents represent a promising therapeutic strategy that is now reaching clinical practice. In this review we describe the results of studies utilizing dual blockade in patients with HER2-positive breast cancer.

Background:Trastuzumab emtansine (T-DM1), a novel drug developed for the treatment of HER2-positive breast cancer, is a human epidermal growth factor receptor (HER2) targeted antibody drug conjugate, composed of trastuzumab, a stable thioether linker, and the potent cytotoxic agent DM1 (derivative of maytansine). It has been shown that, in preclinical studies, it has anti-tumor activity in trastuzumab refractory cancer cells. In this review, we aim to show the clinical data about trastuzumab-DM1 (T-DM1) therapy and to discuss the therapy advantages for the management of patients with HER2-positive breast cancer.Scope:T-DM1 showed positive results in clinical studies of HER2-positive metastatic breast cancer. PubMed database, ASCO and San Antonio Breast Cancer Symposium Meeting abstracts were searched up to September 2012 by using the terms ‘trastuzumab emtansine (T-DM1) and anti-HER2 treatment’; papers which were considered relevant for the aim of this review were selected by the authors.Findings:The phase III randomized trial EMILIA has shown that T-DM1 provided objective tumor responses and significantly improved progression free survival and overall survival compared to lapatinib and capacitabine combination in HER2-positive metastatic breast cancer patients treated with a prior taxane and trastuzumab regimen. It is believed that T-DM1 will play a role in the management of patients with advanced and early stage HER2-positive breast cancer, but this awaits further study. In particular, the ongoing phase III trials MARIANNE and TH3RESA will further give information about the place of T-DM1 in the treatment algorithms for HER2-positive disease.Conclusion:The trials of T-DM1 as a single agent and in combination with other chemotherapies have shown clinical activity and a favorable safety profile in patients with HER2-positive metastatic breast cancer. There are ongoing studies of T-DM1 showing an increasing tendency towards moving the study of these agents to earlier stages of HER2-positive breast cancer.

Herceptin: A First Assault on Oncogenes that Launched a Revolution

Background: HER2-positive breast cancer is a breast cancer that tests positive with human epidermal growth factor receptor 2 (HER2). Human Epidermal Growth Factor Receptor-2 (HER2) promotes the proliferation of breast cancers cells. This research aimed to find the bioactive compounds from Allium sativum for inhibiting HER2 enzyme by using molecular docking method. Materials and method: The protein tyrosin kinase HER2 structure was obtained from Protein Data Bank. Compounds were collected from previous publications of Allium sativum and these structures were retrieved from PubChem database. Molecular docking was done by Autodock vina software. Lipinski’s rule of 5 is used to compare compounds with drug-like and non-drug-like properties. Pharmacokinetic parameters of potential compounds were evaluated using the pkCSM tool. Results: Based on previous publication of Allium sativum, we have collected 55 compounds. The results showed that 2 compounds have HER2 inhibitory activity stronger than the reference compounds including biochanin A và cyanidin 3-malonylglucoside. The Lipinski’s rule of Five showed that these two compounds had propietary drug-likenesss. Moreover, predict ADMET of these compounds was also analyzed. Conclusion: Therefore, biochanin A and cyanidin 3-malonylglucoside may be potential natural product compounds for HER2-positive breast cancer treatment.
 Keywords:
 Allium sativum, tyrosin kinase HER2, breast cancer HER2 positive, in silico, molecular docking.
 References
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Objective:Phosphatase and tensin homolog (PTEN) loss or activating mutations of phosphoinositol-3 (PI3) kinase (PIK3CA) may be related to trastuzumab resistance in in vitro studies; however, this issue in clinical studies is controversial. Therefore, we conducted a meta-analysis to assess the association between PTEN loss, PIK3CA mutation and the efficacy of trastuzumab-based treatment in HER2-positive breast cancer patients.Methods:A computerized search was performed through the PubMed database, the online proceedings of the American Society of Clinical Oncology Annual Meetings, the San Antonio Breast Cancer Symposium and the International St. Gallen Breast Cancer Conference. Ten eligible studies including 1889 cases were identified.Results:In HER2-positive locally advanced breast cancer patients, neither PTEN loss, PIK3CA mutation nor PI3K activation was associated with the response rate of trastuzumab-based neoadjuvant treatment (PTEN loss: RR = 0.687, 95% CI: 0.439–1.074, P = 0.099; PIK3CA mutation: RR = 1.114, 95% CI: 0.453–2.735, P = 0.814; PI3K activation: RR = 0.787, 95% CI: 0.417–1.484, P = 0.459; RR = 0.772, 95% CI: 0.387–1.539, P = 0.462). In HER2-positive early stage breast cancer patients, PTEN loss was not associated with the disease-free survival (DFS) rate of trastuzumab-based adjuvant treatment (HR = 1.096, 95% CI: 0.706–1.700, P = 0.684). In HER2-positive recurrent or metastatic breast cancer patients, PTEN loss was significantly correlated with poorer efficacy of trastuzumab-based salvage treatment (RR = 0.682, 95% CI: 0.550–0.846, P = 0.000).Conclusions:In HER2-positive recurrent or metastatic breast cancer patients PTEN loss might indicate resistance to trastuzumab-based salvage treatment. Due to the small sample size and the considerable heterogeneity in the chemotherapy treatment regimens, further research is needed to clarify the association between PTEN loss, PIK3CA mutation and the efficacy of trastuzumab-based treatment in neoadjuvant and adjuvant settings.

Purpose: We aimed to investigate whether estrogen receptor (ER) status affects the predictive role of the human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) score on the efficacy of neoadjuvant treatment for HER2-positive breast cancer. Methods: This retrospective study comprised 167 individuals diagnosed with HER2-positive invasive breast cancer who had undergone neoadjuvant treatment and surgery. Uni- and multivariable logistic regression analyses were performed on the relationship between the HER2 IHC score and total pathological complete response (tpCR), breast pathological complete response (bpCR), or axillary partial response (apCR). Subgroup analyses were used to investigate whether the relationship between the HER2 IHC score and tpCR, bpCR, or apCR differed by ER or PR status. Results: The overall tpCR rate for HER2-positive breast cancers treated with neoadjuvant treatment was 41.32% (69 of 167). The tpCR, bpCR, and apCR rates were greater in the HER2 IHC 3+ group (tpCR: IHC 3 + 47.69% vs. IHC 2 + 18.92%, p=0.009). Significant interactions between HER2 IHC score and tpCR or bpCR were found in subgroup analyses based on ER status (tpCR: p for interaction = 0.001; bpCR: p for interaction = 0.001). Among ER-positive patients, the HER2 IHC 2+ group had substantially decreased tpCR, bpCR, and apCR rates than the HER2 IHC 3+ group (tpCR rate: p=0.003; bpCR rate: p=0.002; apCR rate: p=0.002). For ER-negative individuals, the tpCR, bpCR, and apCR rates did not differ significantly among the HER2 IHC 3+ versus HER2 IHC 2+ groups. Similarly, interactions between HER2 IHC score and tpCR, bpCR, or apCR were found in subgroup analyses based on PR status. Conclusion: HER2 IHC 2+ may indicate a decreased tpCR rate, bpCR rate, and apCR rate to neoadjuvant treatment in HR-positive patients having HER2-positive breast cancer, but not in HR-negative patients.

Background: Pathological complete response (pCR) after neoadjuvant systemic treatment represents a good surrogate marker for the prognosis of Her-2 positive Breast Cancer (BCs). The results improved after adding anti-Her-2 therapy to chemotherapy in neoadjuvant setting. Methods: Our retrospective study enrolled a cohort of 56 invasive Her-2 positive non-metastatic BCs treated with neoadjuvant systemic therapy between 2001 and 2018. The patients received neoadjuvant chemotherapy with or without anti-Her-2 therapies before surgery and adjuvant endocrine and anti-Her-2 treatment together with adjuvant radiotherapy, based on clinical, pathological and hormonal receptor expression characteristics. The primary end point was pCR rate and disease-free-survival (DFS), defined as the interval between surgery and documented disease recurrence, progression, or death from any cause. Results: The rate of pCR for our patients was 41% independent of type of chemotherapy regimen and the anti-Her-2 therapy used. The results were improved by adding Trastuzumab in the neoadjuvant setting with statistical significance (p = 0.038). Median DFS was 68 months for the entire cohort. The risk of recurrence was higher in the group without pCR after neoadjuvant treatment (52% vs 17%; p = 0.003). 10 patients died (18%), all of them from group without pCR. The prognosis at 36-months was good, with 84% survival chance at 3 years follow-up. Conclusion: Our retrospective study underlines the positive impact of neoadjuvant systemic treatment on pCR rate and on disease-free survival in real-life Her-2 positive breast cancer patients.

Background: Pathological complete response (pCR) after neoadjuvant systemic treatment represents a good surrogate marker for the prognosis of Her-2 positive Breast Cancer (BCs). The results improved after adding anti-Her-2 therapy to chemotherapy in neoadjuvant setting. Methods: Our retrospective study enrolled a cohort of 56 invasive Her-2 positive non-metastatic BCs treated with neoadjuvant systemic therapy between 2001 and 2018. The patients received neoadjuvant chemotherapy with or without anti-Her-2 therapies before surgery and adjuvant endocrine and anti-Her-2 treatment together with adjuvant radiotherapy, based on clinical, pathological and hormonal receptor expression characteristics. The primary end point was pCR rate and disease-free-survival (DFS), defined as the interval between surgery and documented disease recurrence, progression, or death from any cause. Results: The rate of pCR for our patients was 41% independent of type of chemotherapy regimen and the anti-Her-2 therapy used. The results were improved by adding Trastuzumab in the neoadjuvant setting with statistical significance (p = 0.038). Median DFS was 68 months for the entire cohort. The risk of recurrence was higher in the group without pCR after neoadjuvant treatment (52% vs 17%; p = 0.003). 10 patients died (18%), all of them from group without pCR. The prognosis at 36-months was good, with 84% survival chance at 3 years follow-up. Conclusion: Our retrospective study underlines the positive impact of neoadjuvant systemic treatment on pCR rate and on disease-free survival in real-life Her-2 positive breast cancer patients.

e13023 Background: Human epidermal growth factor receptor-2 (HER2) positive breast cancer is a growing concern due to the boom in anti-HER2 therapy. Trastuzumab as the most classic anti-HER2 therapy drug, combined with chemotherapy has become the standard first-line treatment for advanced HER2-positive (HER2+) patients. Although some real-world studies of trastuzumab have been reported, less is known about the role of hormone receptors (HR) in first-line combined therapy. For maintenance therapy after chemotherapy combined with anti-HER2 therapy, the guidance given by clinical trials is the maintenance of targeted therapy. However, for those with HER2+/HR-positive (HR+) breast cancer, whether adding endocrine maintenance therapy can benefit progression-free survival (PFS) in addition to anti-HER2 therapy still needs more research. Thus, the purpose of this study was to retrospectively analyze real-world data, determine the factors that influence the trastuzumab-based therapy in advanced HER2-positive breast cancer patients. Methods: We retrospectively collected the treatment information of advanced breast cancer patients underwent first-line chemotherapy with trastuzumab from 2012 to 2021 in Zhejiang Cancer Hospital. Kaplan–Meier analysis and Cox regression methods were used to calculate and compare the PFS. Results: The study finally enrolled 285 patients meeting the requirement, including 150 HER2+/HR-negative (HR-) and 135 HER2+/HR+ (triple-positive) patients. The median chemotherapy treatment cycles and trastuzumab cycles were 7 (6-8) and 12 (7-17) cycles, respectively. For triple-positive breast cancer, maintenance endocrine therapy was aslo given concurrently with trastusumab in 75 patients after chemotherapy and trastusumab. Overally, the median PFS of first-line treatment was 11.73 (10.16-13.30) months, which was consistent with literature reports. Multivariate analysis revealed that HR positive [hazard ratio, 0.69; 95% confidence interval (CI), 0.52–0.92; P= 0.010], and non-brain metastasis (hazard ratio, 0.54; 95% CI, 0.29–0.99; P= 0.048) were independent prognostic factors. Further Kaplan–Meier analysis demonstrated triple-positive patients with maintenance endocrine therapy significantly had longer PFS than triple-positive patients without maintenance endocrine therapy and HER2+/HR- patients (21.33m vs. 10.13m vs. 9.53m, respectively, P < 0.001). Conclusions: HR-positive was an independent prognostic factor for HER2-positive advanced breast cancer patients receiving first-line chemotherapy with trastuzumab. And endocrine therapy combined trastuzumab as Maintenance after chemotherapy prolonged PFS in HR-positive subgroup patients.

Background: Trastuzumab has been used for HER2 positive breast cancer treatment for more than 20 years. The ratio of HER2 overexpression in breast cancer patients is about 20%. In this study, we aim to evaluate the prognosis of HER2 positive breast cancer patients with long term received trastuzumab and examined the predictors of complete response. Method: In this study, we included the patients with HER2 positive metastatic breast cancer received long-term trastuzumab. Demographic, clinical, pathological, and treatment data of the patients retrospectively recorded. Response rates of trastuzumab-based treatment evaluated by RECIST. The prognosis of the patients and predictors of complete response assessed with Kaplan-Meier analysis and logistic regression analysis, respectively. Also, the prognosis of the patients whose trastuzumab-based treatment was terminated was evaluated. Results: Median follow-up was 123.3 months (range, 32.2-330.3). Eighty patients included the study, and the median age of the patients was 43 (22-68). The patients received trastuzumab-based treatment with a median of 62 months (range, 12-191). The number of de-novo metastatic patients was 27 (33.8%). All patients had a pathological HER2 overexpressed tumor that scored 3+ (71.3%) by ımmunohistochemistry (IHC) or scored 2+ (28.7%) by IHC confirmed with FISH. In all patients, five-, ten-, and, fifteen – years overall survival were 96.1%, 86.8%, and 60.5%, respectively. A complete response was detected at 60 (75%) of the patients. The median time to complete response was 14.4 months (range, 2.4-47.8). In logistic-regression analysis: age at diagnosis (p=0.543), menopausal status (p=0.074), bisphosphonates treatment (p=0.682), palliative radiotherapy (p=0.935), and de-novo metastatic disease (p=0.405) were not statistically significant predictors for complete response. However, the number of metastatic sites (p=0.016), and the use of endocrine therapy (p=0.019) with trastuzumab were statistically significant. During the study period, trastuzumab-based treatment of twelve patients was terminated, four (33.3%) patients continue to receive aromatase inhibitör, and eight (66.7%) patients received no treatment. After termination of trastuzumab, at a median follow-up 44.7 months (range, 11.6-66.6), recurrence was not detected in the patients. Conclusions: In this study, we found that trastuzumab-based therapy can provide full recovery of HER2 positive metastatic breast cancer. For the patients with a long-term complete response, discontinuation of trastuzumab-based treatment should be considered. Also, hormone-positive patients should continue to receive aromatase inhibitör. The use of endocrine therapy with trastuzumab and the number of metastatic sites are predictors of the complete response Citation Format: Izzet Dogan, Esra Aydın, Nijat Khanmammadov, Adnan Aydıner, Pınar Saip. Termination of trastuzumab-based treatment after complete response in HER2-positive metastatic breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS10-44.

Objective To better understand the status of medical treatment for human epidermal growth factor receptor 2 (HER2)-positive breast cancer and the differences between the Chinese and the international clinical practice. Methods This was a retrospective, nationwide, multicenter, epidemiological study of advanced breast cancer patients from China. Between January 01, 2012, and December 31, 2014, a total of 3649 patients, covering 7 geographic regions and 21 institutions, participated in this series of studies. HER2-positive breast cancer was selected among the group and adopted into this study. In comparison, we summarized the demographics and clinical characteristics of HER2-positive breast cancer from the Surveillance, Epidemiology, and End Results (SEER) database. Results A total of 918 patients diagnosed as HER2-positive breast cancer patients were included. The median age at diagnosis was 46 years (ranging, 23 to 78) with a single-peak incidence. The proportions of stages II–IV at diagnosis and distance metastasis in viscera were more than half of the participants. In comparison, the prevalence of estrogen or progesterone receptor-positive expression and luminalB subtype was relatively lower than that of the United States. The receipt of chemotherapy was fairly higher, while the usage of targeted therapy was seriously insufficient. Tumor size was in significantly positive associations with the duration of targeted therapy (Kendall's correlation coefficient = 0.3, P < 0.0001), while no prohibitive variables among clinical characteristics were detected. Conclusion Our study suggested that HER2-positive breast cancer patients were characterized as a younger trend, a lower prevalence of hormonal receptor (HR)-positive expression, and less accessible to anti-HER2 targeted therapy with insufficient duration over the past few years in China. Concerted efforts should be exerted for promising survival benefits in the future. The trial registration number is https://clinicaltrials.gov/ct2/show/NCT03047889.

Impacts of HER2 immunohistochemical scores on response and outcomes of HER2-positive breast cancers after neoadjuvant therapy