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Lavina Bharwani

Bio: Lavina Bharwani is an academic researcher from Baylor College of Medicine. The author has contributed to research in topics: Medicine & Internal medicine. The author has an hindex of 5, co-authored 5 publications receiving 848 citations.

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TL;DR: A strategy of combining endocrine therapy (particularly tamoxifen) with these inhibitors, to circumvent de novo and acquired resistance, will be discussed.
Abstract: Introduced more than 100 years ago, endocrine therapy is still the most important systemic therapy for all stages of estrogen receptor (ER) -positive breast tumors. A major clinical problem limiting the usefulness of this therapy is tumor resistance, either de novo or acquired during the course of the treatment. Relatively new discoveries emphasize the complexity of ER signaling and its multiple regulatory interactions with growth factor and other kinase signaling pathways. Both genomic (nuclear) and nongenomic (membrane and cytoplasmic) ER activities contribute to this intimate cross-talk, which is probably a fundamental factor in endocrine resistance. New targeted therapies, especially against the epidermal growth factor receptor/HER-2 pathway, should be carefully evaluated in more (bio)logical strategies to enable them to be exploited appropriately. A strategy of combining endocrine therapy (particularly tamoxifen) with these inhibitors, to circumvent de novo and acquired resistance, will be discussed. We will also emphasize open questions and future challenges in the dynamic research field of molecular ER biology from the endocrine therapy perspective.

431 citations

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TL;DR: Combined treatment with gefitinib, trastuzumab, and pertuzumAB to block signals from all HER homo- and heterodimers inhibited growth of HER2-overexpressing xenografts statistically significantly better than single agents and dual combinations.
Abstract: BACKGROUND Human epidermal growth factor receptor 2 (HER2) is a member of the HER signaling pathway. HER inhibitors partially block HER signaling and tumor growth in preclinical breast cancer models. We investigated whether blockade of all HER homo- and heterodimer pairs by combined treatment with several inhibitors could more effectively inhibit tumor growth in such models. METHODS Mice carrying xenograft tumors of HER2-overexpressing MCF7/HER2-18 (HER2-transfected) or BT474 (HER2-amplified) cells were treated with estrogen supplementation or estrogen withdrawal, alone or combined with tamoxifen. One to three HER inhibitors (pertuzumab, trastuzumab, or gefitinib) could also be added (n > or = 8 mice per group). Tumor volumes, HER signaling, and tumor cell proliferation and apoptosis were assessed. Results were analyzed with the t test or Wilcoxon rank sum test and survival analysis methods. All statistical tests were two-sided. RESULTS Median time to tumor progression was 21 days for mice receiving estrogen and 28 days for mice receiving estrogen and pertuzumab (difference = 7 days; P = .001; hazard ratio [HR] of progression in mice receiving estrogen and pertuzumab versus mice receiving estrogen = 0.27, 95% confidence interval [CI] = 0.09 to 0.77). Addition of gefitinib and trastuzumab to estrogen and pertuzumab increased this time to 49 days (difference = 21 days; P = .004; HR of progression = 0.28, 95% CI = 0.10 to 0.76). MCF7/HER2-18 tumors disappeared completely and did not progress (for > or = 189 days) after combination treatment with pertuzumab, trastuzumab, and gefitinib plus tamoxifen (19 of 20 mice) or plus estrogen withdrawal (14 of 15 mice). Both combination treatments induced apoptosis and blocked HER signaling and proliferation in tumor cells better than any single agent or dual combination. All BT474 tumors treated with pertuzumab, trastuzumab, and gefitinib disappeared rapidly, regardless of endocrine therapy, and no tumor progression was observed for 232 days. CONCLUSION Combined treatment with gefitinib, trastuzumab, and pertuzumab to block signals from all HER homo- and heterodimers inhibited growth of HER2-overexpressing xenografts statistically significantly better than single agents and dual combinations.

194 citations

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TL;DR: Compelling experimental and clinical evidence suggest that the epidermal growth factor/her2/neu receptor (EGFR/HER2) pathway might play a distinct role in endocrine resistance, and especially in resistance to selective estrogen receptor modulators (SERMs) such as tamoxifen.
Abstract: Estrogen receptor (ER), mediating estrogen-signaling stimuli, is a dominant regulator and a key therapeutic target in breast cancer etiology and progression. Endocrine therapy, blocking the ER pathway, is one of the most important systemic therapies in breast cancer management, but de novo and acquired resistance is still a major clinical problem. New research highlights the role of both genomic and nongenomic ER activities and their intimate molecular crosstalk with growth factor receptor and other signaling kinase pathways in endocrine resistance. These signaling pathways, when overexpressed and/or hyperactivated, can modulate both activities of ER, resulting in endocrine resistance. Thus, these signal transduction receptors and signaling molecules may serve as both predictive markers and novel therapeutic targets to circumvent endocrine resistance. Compelling experimental and clinical evidence suggest that the epidermal growth factor/HER2/neu receptor (EGFR/HER2) pathway might play a distinct role in endocrine resistance, and especially in resistance to selective estrogen receptor modulators (SERMs) such as tamoxifen. Results from preclinical studies of treatment combinations with various endocrine therapy drugs together with several potent anti-EGFR/HER2 inhibitors are very promising, and clinical trials to see whether this new strategy is effective in patients are now ongoing.

146 citations

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TL;DR: Almost all of the TF in the patient's plasma was associated with cell‐derived microvesicles, likely shed by the cancer cells, and found its concentration in his plasma to be forty‐one‐fold higher than the mean concentration derived from testing of 16 normal individuals.

106 citations

Journal ArticleDOI
TL;DR: Longer time to fever onset, lower platelet count and higher urea at presentation were associated with Grade 3-5 CRS, and these parameters may be used to predict which patients are likely to develop severe CRS.
Abstract: Cytokine release syndrome (CRS) is a phenomenon of immune hyperactivation described in the setting of immunotherapy. Unlike other immune-related adverse events, CRS triggered by immune checkpoint inhibitors (ICIs) is not well described. The clinical characteristics and course of 25 patients with ICI-induced CRS from 2 tertiary hospitals were abstracted retrospectively from the medical records and analyzed. CRS events were confirmed by 2 independent reviewers and graded using the Lee et al. scale. The median duration of CRS was 15.0 days (Q1; Q3 6.3; 29.8) and 10 (40.0%) had multiple episodes of CRS flares. Comparing the clinical factors and biomarkers in Grades 1-2 and 3-5 CRS, we found that patients with Grades 3-5 CRS had following: (i) had longer time to fever onset [25.0 days (Q1; Q3 13.0; 136.5) vs. 3.0 days (Q1; Q3 0.0; 18.0), p=0.027]; (ii) more cardiovascular (p=0.002), neurologic (p=0.001), pulmonary (p=0.044) and rheumatic (p=0.037) involvement; (iii) lower platelet count (p=0.041) and higher urea (p=0.041) at presentation compared to patients with Grades 1-2 CRS. 7 patients (28.0%) with Grades 1-2 CRS were rechallenged using ICIs without event. 9 patients (36.0%) were treated with pulse methylprednisolone and 6 patients (24.0%) were treated with tocilizumab. Despite this, 3 patients (50%) who received tocilizumab had fatal (Grade 5) outcomes from ICI-induced CRS. Longer time to fever onset, lower platelet count and higher urea at presentation were associated with Grade 3-5 CRS. These parameters may be used to predict which patients are likely to develop severe CRS.

21 citations


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TL;DR: This work discusses the significance of these receptors as clinical targets, in particular the molecular mechanisms underlying response, and many ERBB inhibitors used in the clinic.
Abstract: ERBB receptor tyrosine kinases have important roles in human cancer. In particular, the expression or activation of epidermal growth factor receptor and ERBB2 are altered in many epithelial tumours, and clinical studies indicate that they have important roles in tumour aetiology and progression. Accordingly, these receptors have been intensely studied to understand their importance in cancer biology and as therapeutic targets, and many ERBB inhibitors are now used in the clinic. We will discuss the significance of these receptors as clinical targets, in particular the molecular mechanisms underlying response.

3,083 citations

Journal ArticleDOI
TL;DR: Everolimus combined with an aromatase inhibitor improved progression-free survival in patients with hormone-receptor-positive advanced breast cancer previously treated with nonsteroidal aromat enzyme inhibitors.
Abstract: A b s t r ac t Background Resistance to endocrine therapy in breast cancer is associated with activation of the mammalian target of rapamycin (mTOR) intracellular signaling pathway. In early studies, the mTOR inhibitor everolimus added to endocrine therapy showed antitumor activity. Methods In this phase 3, randomized trial, we compared everolimus and exemestane versus exemestane and placebo (randomly assigned in a 2:1 ratio) in 724 patients with hormone-receptor–positive advanced breast cancer who had recurrence or progression while receiving previous therapy with a nonsteroidal aromatase inhibitor in the adjuvant setting or to treat advanced disease (or both). The primary end point was progression-free survival. Secondary end points included survival, response rate, and safety. A preplanned interim analysis was performed by an independent data and safety monitoring committee after 359 progression-free survival events were observed. Results Baseline characteristics were well balanced between the two study groups. The median age was 62 years, 56% had visceral involvement, and 84% had hormone-sensitive disease. Previous therapy included letrozole or anastrozole (100%), tamoxifen (48%), fulvestrant (16%), and chemotherapy (68%). The most common grade 3 or 4 adverse events were stomatitis (8% in the everolimus-plus-exemestane group vs. 1% in the placebo-plus-exemestane group), anemia (6% vs. <1%), dyspnea (4% vs. 1%), hyperglycemia (4% vs. <1%), fatigue (4% vs. 1%), and pneumonitis (3% vs. 0%). At the interim analysis, median progression-free survival was 6.9 months with everolimus plus exemestane and 2.8 months with placebo plus exemestane, according to assessments by local investigators (hazard ratio for progression or death, 0.43; 95% confi dence interval [CI], 0.35 to 0.54; P<0.001). Median progression-free survival was 10.6 months and 4.1 months, respectively, according to central assessment (hazard ratio, 0.36; 95% CI, 0.27 to 0.47; P<0.001). Conclusions Everolimus combined with an aromatase inhibitor improved progression-free survival in patients with hormone-receptor–positive advanced breast cancer previously treated with nonsteroidal aromatase inhibitors. (Funded by Novartis; BOLERO-2 ClinicalTrials .gov number, NCT00863655.)

2,388 citations

Journal ArticleDOI
TL;DR: This review focuses on various strategies for purifying exosomes and discusses their biophysical and biochemical properties, and an update on proteomic analysis of exosome from various cell types and body fluids is provided and host-cell specific proteomic signatures are discussed.

2,093 citations

Journal ArticleDOI
TL;DR: This review focuses on several of the interesting recent discoveries concerning estrogen receptors, on estrogen as a morphogen, and on the molecular mechanisms of anti-estrogen signaling.
Abstract: During the past decade there has been a substantial advance in our understanding of estrogen signaling both from a clinical as well as a preclinical perspective. Estrogen signaling is a balance bet...

1,652 citations

Journal ArticleDOI
TL;DR: Among patients with hormone-receptor-positive metastatic breast cancer who had progression of disease during prior endocrine therapy, palbociclib combined with fulvestrant resulted in longer progression-free survival than fulvestrants alone.
Abstract: BackgroundGrowth of hormone-receptor–positive breast cancer is dependent on cyclin-dependent kinases 4 and 6 (CDK4 and CDK6), which promote progression from the G1 phase to the S phase of the cell cycle. We assessed the efficacy of palbociclib (an inhibitor of CDK4 and CDK6) and fulvestrant in advanced breast cancer. MethodsThis phase 3 study involved 521 patients with advanced hormone-receptor–positive, human epidermal growth factor receptor 2–negative breast cancer that had relapsed or progressed during prior endocrine therapy. We randomly assigned patients in a 2:1 ratio to receive palbociclib and fulvestrant or placebo and fulvestrant. Premenopausal or perimenopausal women also received goserelin. The primary end point was investigator-assessed progression-free survival. Secondary end points included overall survival, objective response, rate of clinical benefit, patient-reported outcomes, and safety. A preplanned interim analysis was performed by an independent data and safety monitoring committee af...

1,109 citations