Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Gayathri Nagaraj is active.

Publication


Featured researches published by Gayathri Nagaraj.


Clinical Cancer Research | 2016

A Phase I Trial of BKM120 (Buparlisib) in Combination with Fulvestrant in Postmenopausal Women with Estrogen Receptor-Positive Metastatic Breast Cancer.

Cynthia X. Ma; Jingqin Luo; Michael Naughton; Foluso O. Ademuyiwa; Rama Suresh; Malachi Griffith; Obi L. Griffith; Zachary L. Skidmore; Nicholas C. Spies; Avinash Ramu; Lee Trani; Timothy J. Pluard; Gayathri Nagaraj; Shana Thomas; Zhanfang Guo; Jeremy Hoog; Jing Han; Elaine R. Mardis; A. Craig Lockhart; Matthew J. Ellis

Purpose: This trial was conducted to determine the maximum tolerated dose (MTD) and preliminary efficacy of buparlisib, an oral pan-class I PI3K inhibitor, plus fulvestrant in postmenopausal women with metastatic estrogen receptor positive (ER+) breast cancer. Experimental Design: Phase IA employed a 3+3 design to determine the MTD of buparlisib daily plus fulvestrant. Subsequent cohorts (phase IB and cohort C) evaluated intermittent (5/7-day) and continuous dosing of buparlisib (100 mg daily). No more than 3 prior systemic treatments in the metastatic setting were allowed in these subsequent cohorts. Results: Thirty-one patients were enrolled. MTD was defined as buparlisib 100 mg daily plus fulvestrant. Common adverse events (AE) included fatigue (38.7%), transaminases elevation (35.5%), rash (29%), and diarrhea (19.4%). C-peptide was significantly increased during treatment, consistent with on-target effect of buparlisib. Compared with intermittent dosing, daily buparlisib was associated with more frequent early onset AEs and higher buparlisib plasma concentrations. Among the 29 evaluable patients, the clinical benefit rate was 58.6% (95% CI, 40.7%–74.5%). Response was not associated with PIK3CA mutation or treatment cohort; however, loss of PTEN, progesterone receptor (PgR) expression, or mutation in TP53 was most common in resistant cases, and mutations in AKT1 and ESR1 did not exclude treatment response. Conclusions: Buparlisib plus fulvestrant is clinically active with manageable AEs in patients with metastatic ER+ breast cancer. Weekend breaks in buparlisib dosing reduced toxicity. Patients with PgR negative and TP53 mutation did poorly, suggesting buparlisib plus fulvestrant may not be adequately effective against tumors with these poor prognostic molecular features. Clin Cancer Res; 22(7); 1583–91. ©2015 AACR.


Journal of Thoracic Oncology | 2013

Review of Ongoing Clinical Trials in Non–Small-Cell Lung Cancer: A Status Report for 2012 from the ClinicalTrials.gov Web Site

Janakiraman Subramanian; Thomas Regenbogen; Gayathri Nagaraj; Alex R. Lane; Siddhartha Devarakonda; Gongfu Zhou; Ramaswamy Govindan

Introduction: Clinical research in non–small-cell lung cancer (NSCLC) is a rapidly evolving field. In an effort to identify the current trends in lung cancer clinical research, we reviewed ongoing clinical trials in NSCLC listed in the ClinicalTrials.gov registry in 2012, and we also compared this data to a similar survey conducted by us in 2009. Methods: The Web site’s advanced search function was used to search for the term “non-small cell lung cancer.” The search was further refined by using the following options from the search page drop-down menu, “open studies” and “interventional.” Studies with non-NSCLC tumor histologies and pediatric studies were excluded. Results: Of the 477 trials included in the analysis, 105 (22.0%) were phase I, 223 phase II (46.8%), and 63 phase III trials (13.2%). When compared with data from 2009, university-sponsored trials decreased in number (45.4%–34.2%; p < 0.001) whereas industry-sponsored trials remained almost the same. There was a significant increase in trials conducted exclusively outside of the United States (35.9%–48.8%; p = 0.001). The number of studies with locations in China (61, 12.8%) was second only to that in the United States (244, 51.2%). Studies reporting biomarker analysis increased significantly from 37.5% to 49.1% in 2012 (p < 0.001). Biomarker-based patient selection also increased significantly from 7.9% to 25.8% (p < 0.001). Targeted therapies were evaluated in 70.6% of phase I/II and II trials, and the most common class of targeted agent studied was epidermal growth factor receptor tyrosine kinase inhibitors (38.0%). Prespecified accrual times were observed to increase when compared with data reported in 2009, especially among industry-sponsored studies. Conclusions: Our survey identified major changes in lung cancer clinical research since 2009. Almost half of all studies registered at the ClinicalTrials.gov Web site are being conducted outside the United States, and several novel molecularly targeted agents are being evaluated in the treatment of patients with NSCLC. More importantly, we identified a threefold increase in the number of studies that perform biomarker testing to determine patient selection over the last 3 years.


Breast Cancer Research and Treatment | 2015

Revisiting the estrogen receptor pathway and its role in endocrine therapy for postmenopausal women with estrogen receptor-positive metastatic breast cancer

Gayathri Nagaraj; Cynthia X. Ma

Endocrine therapy (ET) is the most commonly administered first-line systemic therapy for estrogen receptor-positive (ER+) metastatic breast cancer (MBC). Manipulation of hormone levels was one of the earliest ET approaches. However, treatment modalities have since evolved with the growing understanding of estrogen biosynthesis and ER biology. The current armamentarium of ET includes selective estrogen receptor modulation, aromatase inhibition, and selective estrogen receptor downregulation. However, intrinsic or acquired resistance to ET is frequently observed. Significant strides have been made in recent years in our understanding of the mechanisms of resistance to ET, and several targeted approaches including inhibitors against the phosphatidylinositol 3-kinase/mammalian target of rapamycin (PI3K/mTOR) pathway and cyclin-dependent kinase 4/6 (CDK4/6) have shown great promise. The mTOR inhibitor, everolimus, is already in clinical use for the treatment of resistant ER+MBC. However, multiple levels of evidence indicate that ER signaling remains as an important therapeutic target even in the resistance setting, providing the rationale for sequencing multiple lines and combinations of ET. In addition, recurrent mutations in estrogen receptor 1 (ESR1), the gene that encodes the ER, have been identified in the genomic studies of metastatic ER+ breast cancer. ESR1 mutations are an important mechanism for acquired resistance, and effective ER targeting in this setting is particularly important.


Hpb | 2015

A phase II study of adjuvant gemcitabine plus docetaxel followed by concurrent chemoradation in resected pancreaticobiliary carcinoma

May Cho; Andrea Wang-Gillam; Robert J. Myerson; Feng Gao; Steven M. Strasberg; Joel Picus; Steven Sorscher; Chloe Fournier; Gayathri Nagaraj; Parag J. Parikh; Rama Suresh; David C. Linehan; Benjamin R. Tan

OBJECTIVES Adjuvant gemcitabine with or without chemoradiation is a standard therapeutic option for patients with resected pancreatic cancer. The feasibility and toxicity of gemcitabine with docetaxel before and after 5-fluorouracil (5FU)-based chemoradiation in the adjuvant pancreatic and biliary cancer setting were investigated. METHODS After a curative-intent resection, eligible patients with pancreaticobiliary cancers were treated with two cycles of gemcitabine and docetaxel followed by 5FU-based chemoradiation. Four weeks after completing chemoradiation, two cycles of gemcitabine and docetaxel were administered. The primary endpoint was the incidence of severe toxicities. Secondary endpoints included disease-free survival (DFS) and overall survival (OS). RESULTS Fifty patients with pancreaticobiliary cancers were enrolled. Twenty-nine patients had pancreatic cancer whereas 21 patients had biliary tract or ampullary cancers. There was one death as a result of pneumonia, and 15% of patients experienced grade 3 or greater non-haematological toxicities. The median DFS and OS for patients with pancreatic cancer were 9.6 and 17 months, respectively, and for those with resected biliary tract cancer were 12 and 23 months, respectively. CONCLUSIONS This combination of gemcitabine and docetaxel with chemoradiation is feasible and tolerable in the adjuvant setting. Future studies utilizing a different gemcitabine/taxane combination and schedule may be appropriate in the adjuvant treatment of both pancreatic cancer and biliary tumours.


Journal of gastrointestinal oncology | 2014

Complete response and prolonged disease-free survival in a patient with recurrent duodenal adenocarcinoma treated with bevacizumab plus FOLFOX6

Gayathri Nagaraj; Yousef Zarbalian; Karin Flora; Benjamin R. Tan

Small bowel adenocarcinoma is an uncommon gastrointestinal malignancy with limited data on effective chemotherapy in the adjuvant setting, as well as for advanced disease. We present a case report of a patient with recurrent duodenal adenocarcinoma after resection and adjuvant chemotherapy who experienced a complete response to bevacizumab with oxaliplatin and 5FU (FOLFOX) followed by bevacizumab/capecitabine maintenance therapy for 2 years. The patient continues to be disease-free 8 years after his recurrence. This case highlights the potential of vascular endothelial growth factor (VEGF) inhibitors to enhance chemotherapeutic regimens for advanced small bowel adenocarcinoma.


Expert Review of Anticancer Therapy | 2016

Complete response in a critically ill patient with ALK-negative anaplastic large cell lymphoma treated with single agent brentuximab-vedotin.

Karlos Z. Oregel; Emily Everett; Xinhai Zhang; Gayathri Nagaraj

ABSTRACT Anaplastic large cell lymphoma (ALCL) is a rare hematological malignancy and a distinct subtype of mature T-cell lymphomas. ALCL is comprised of two clinically distinct but morphologically similar sub-class under 2008 WHO classification: cutaneous and systemic. Primary systemic ALCL is further sub-categorized into tumors that carry the anaplastic lymphoma kinase (ALK) gene rearrangement or not; ALK-positive versus ALK-negative disease respectively. Traditionally, both forms of primary systemic ALCL have been treated upfront with an anthracycline based combination chemotherapy such as CHOP. More recently an antibody drug conjugate, brentuximab-vedotin (BV), directed against CD30 antigen has shown promise in CD30 expressing hematologic malignancies such as Hodgkins lymphoma and ALCL. At the present time, this novel antibody-drug conjugate has been approved in the treatment of patients with ALCL after failure of at least one prior multi-agent chemotherapy regimen in the United States. We present a case describing a previously healthy 48 year-old female diagnosed with ALK-negative ALCL who achieved complete response with upfront single agent brentuximab-vedotin. It is the first case described in the literature utilizing BV in the first line setting particularly in a patient with multi-organ failure and critically ill at time of diagnosis. This case highlights the full potential that targeted therapies can exert over hematological malignancies while also minimizing treatment related toxicities. Abbreviations: AE: adverse event; ALCL: anaplastic large cell lymphoma; ALK: anaplastic lymphoma kinase; ASCT: autologous stem cell transplant; BEAM: BCNU/carmustine, etoposide, ara-C, and melphalan; BV: brentuximab vedotin; CHEOP: cyclophosphamide, daunorubicin, vincristine, prednisone, etoposide; CHOP: cyclophosphamide, doxorubicin, vincristine, prednisone; CR:complete response; G3+: grade 3 or higher; MTD: maximum tolerated dose; ORR: overall response rate; OS: overall survival; PFS: progression-free survival.


Journal of Cellular Physiology | 2018

AhR ligand aminoflavone suppresses α6-integrin-Src-Akt signaling to attenuate tamoxifen resistance in breast cancer cells: CAMPBELL et al.

Petreena Campbell; Nicole Mavingire; Salma Khan; Leah Rowland; Jonathan Wooten; Anna Opoku-Agyeman; Ashley Guevara; Ubaldo Soto; Fiorella Cavalli; Andrea Loaiza-Perez; Gayathri Nagaraj; Laura J. Denham; Olayemi O. Adeoye; Brittany D. Jenkins; Melissa B. Davis; Rachel Schiff; Eileen Brantley

More than 40% of patients with luminal breast cancer treated with endocrine therapy agent tamoxifen demonstrate resistance. Emerging evidence suggests tumor initiating cells (TICs) and aberrant activation of Src and Akt signaling drive tamoxifen resistance and relapse. We previously demonstrated that aryl hydrocarbon receptor ligand aminoflavone (AF) inhibits the expression of TIC gene α6‐integrin and disrupts mammospheres derived from tamoxifen‐sensitive breast cancer cells. In the current study, we hypothesize that tamoxifen‐resistant (TamR) cells exhibit higher levels of α6‐integrin than tamoxifen‐sensitive cells and that AF inhibits the growth of TamR cells by suppressing α6‐integrin–Src–Akt signaling. In support of our hypothesis, TamR cells and associated mammospheres were found to exhibit elevated α6‐integrin expression compared with their tamoxifen‐sensitive counterparts. Furthermore, tumor sections from patients who relapsed on tamoxifen showed enhanced α6‐integrin expression. Gene expression profiling from the TCGA database further revealed that basal‐like breast cancer samples, known to be largely unresponsive to tamoxifen, demonstrated higher α6‐integrin levels than luminal breast cancer samples. Importantly, AF reduced TamR cell viability and disrupted TamR mammospheres while concomitantly reducing α6‐integrin messenger RNA and protein levels. In addition, AF and small interfering RNA against α6‐integrin blocked tamoxifen‐stimulated proliferation of TamR MCF‐7 cells and further sensitized these cells to tamoxifen. Moreover, AF reduced Src and Akt signaling activation in TamR MCF‐7 cells. Our findings suggest elevated α6‐integrin expression is associated with tamoxifen resistance and AF suppresses α6‐integrin–Src–Akt signaling activation to confer activity against TamR breast cancer.


Hematology Reviews | 2018

Acquired factor VII deficiency causing severe bleeding disorder secondary to AL amyloidosis of the liver

Anthony L. Nguyen; Muhammad Kamal; Ravi Raghavan; Gayathri Nagaraj

A 52 year-old male presented with neck pain after undergoing thyroidectomy for a goiter three weeks prior which was complicated by a neck hematoma requiring evacuation. Computed tomography (CT) scan showed a neck hematoma requiring evacuation and he received desmopressin with cessation of bleeding. Coagulation studies were normal. He returned eighteen months later with severe oral mucosal bleeding after a dental procedure and required transfusions with red blood cells, platelets, and fresh frozen plasma (FFP) in addition to desmopressin, Humate-P, aminocaproic acid, and surgical packing. A comprehensive bleeding diathesis workup was normal. He was readmitted six months later due to abdominal pain and distention and found to have massive hepatosplenomegaly on CT. A new coagulopathy workup revealed prolonged INR to 1.5, corrected prothrombin time mixing study, and a low factor VII level (29%), suggesting acquired factor VII deficiency. A transjugular liver biopsy revealed extensive involvement by ALamyloidosis- Kappa type. He then developed a large right retroperitoneal hematoma which required multiple transfusions with FFP, cryoprecipitate, aminocaproic acid, and vitamin K with slight success. Hemorrhage was subsequently stabilized with recombinant factor VIIa administered every four hours which corresponded with correction of factor VII levels and PT and eventual cessation hemorrhage. Acquired factor VII deficiency causing severe coagulopathy was attributed to hepatic amyloidosis ALkappa subtype. We started treatment with bortezomib, dexamethasone, and cyclophosphamide, however, the patient succumbed to uncontrolled hemorrhage. Acquired factor VII deficiency is extremely rare and to our knowledge, this is the only known case of factor VII deficiency secondary to amyloidosis involving the liver.


Cancer Medicine | 2018

Disparities in breast cancer: a multi‐institutional comparative analysis focusing on American Hispanics

Zeina A. Nahleh; Salman Otoukesh; Hamid R. Mirshahidi; Anthony L. Nguyen; Gayathri Nagaraj; Gehan Botrus; Nabeel Badri; Nabih Diab; Andres Alvarado; Luis A. Sanchez; Alok Dwivedi

Breast cancer (BC) is the leading cause of cancer death in Hispanic/Latino women nationwide. Hispanic women are more likely to be presented with advanced disease and adverse prognosis subtypes. The aim of this study is to describe the clinico‐ pathological characteristics and disparities in breast cancer in this group at two tertiary care University‐based medical centers. After IRB approval, Cancer registry was used to analyze the variables of 3441 patients with breast cancer diagnosed and treated consecutively at two large tertiary University based medical and cancer center database centers in El Paso, TX and Loma Linda, CA between 2005 and 2015. Association between race/ethnicity and cancer type, stage, hormone receptor status and treatment option were investigated. Overall 45.5% of the patients were Hispanic (n: 1566) and those were more likely to be diagnosed at a younger age (57 years) similar to African Americans, more likely to have invasive ductal carcinoma type (82.7%) & triple negative disease (17.1%, 95%CI: 15% to 19%). 58.8% of Hispanics (95%CI: 56% to 61%) have hormone receptor (HR)+ & HER2− as opposed to 71% in non‐Hispanic White people. In addition, Hispanic individuals presented with advanced stages of BC (25.3%, 95% CI: 23% to 28%) similar to African American (25.4%), and had a lower proportion of lumpectomy (50%) similar to African American (50%). When compared to African American patients, Hispanic patients had a higher prevalence of triple negative BC (17.11% in Hispanics Versus 13.86% in African American). Conclusion: Hispanics had significantly higher relative risk of advanced stages at presentation (Relative Risk Ratio (RRR) = 2.05, P < 0.001), triple negative tumors (RRR = 2.64, P < 0.0001), HER2 + /HR ‐ disease (RRR = 1.77, P < 0.0001), and less HR+ /HER2− BC (RRR = 0.69, P < 0.0001). Hispanics and African Americans are diagnosed with breast cancer at a younger age, have a higher prevalence of Triple negative breast cancer, and are diagnosed at more advanced stages of disease. Increasing awareness and targeting minority populations for health promotion interventions, screening and early detection continue to be of paramount importance to reduce the burden of health disparities.


Cancer Research | 2017

Abstract 4177: Anticancer agent Aminoflavone restores the expression of tumor suppressor miRNA 26a and inhibits putative stemness biomarker α6-integrin in Tamoxifen resistant cells

Petreena Campbell; Leah Rowland; Anna Opoku-Agyeman; Nichole Mavingire; Ubaldo Soto; Gayathri Nagaraj; Yonghong Zhang; Sean Chen; Charles Wang; Eileen Brantley

Despite the efficacy of anti-estrogen agent Tamoxifen, commonly used to treat patients with estrogen receptor positive (ER + ) tumors, up to 40% of patients experience recurrence. Breast tumor-initiating cells (TICs), or breast cancer stem cells, exhibit Tamoxifen resistance and contribute substantially to recurrence. We recently demonstrated that investigational anticancer agent Aminoflavone (AF) disrupts mammospheres (in vitro clusters of cells enriched with TICs) by thwarting the expression of α6-integrin. In the current study, we found AF potently inhibited Tamoxifen resistant (TamR) cell growth and blocked Tamoxifen-mediated stimulation of TamR cell proliferation using the Alamar Blue assay. qPCR analyses revealed α6-integrin expression was significantly elevated in ER + breast cancer cell models of acquired and de novo Tamoxifen resistance relative to Tamoxifen sensitive cells. In particular, AF decreased the expression of both A and B variants of α6-integrin, the B variant being essential for TIC function. Western blotting revealed AF reduced total α6-integrin expression in TamR cells. Furthermore, we found that an anti-α6-integrin blocking antibody sensitized TamR cells to the active Tamoxifen metabolite, 4-hydroxy-Tamoxifen, and enhanced the efficacy of AF in these cells. AF also reduced the protein expression of p-Src, a downstream target of α6-integrin that is linked to Tamoxifen resistance and decreased breast cancer survival. In addition, miRNA sequencing of Tamoxifen sensitive and TamR mammospheres revealed differential expression of several miRNAs. Notably, miR-26a expression was down-regulated 2-fold in TamR mammospheres compared to Tamoxifen sensitive mammospheres and AF restored miR-26a expression 5-fold in TamR mammospheres. Using miRNA target prediction algorithms TargetScan and PicTar, we found miR-26a binding sites on the α6-integrin promoter. Taken together, our data suggest that AF re-expresses tumor suppressor miR-26a and inhibits the α6-integrin/Src signaling axis to reduce TIC capacity and counteract Tamoxifen resistance. Citation Format: Petreena Campbell, Leah Rowland, Anna Opoku-Agyeman, Nichole Mavingire, Ubaldo Soto, Gayathri Nagaraj, Yonghong Zhang, Sean (Xin) Chen, Charles Wang, Eileen Brantley. Anticancer agent Aminoflavone restores the expression of tumor suppressor miRNA 26a and inhibits putative stemness biomarker α6-integrin in Tamoxifen resistant cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4177. doi:10.1158/1538-7445.AM2017-4177

Collaboration


Dive into the Gayathri Nagaraj's collaboration.

Top Co-Authors

Avatar

Cynthia X. Ma

Washington University in St. Louis

View shared research outputs
Top Co-Authors

Avatar

Matthew J. Ellis

Baylor College of Medicine

View shared research outputs
Top Co-Authors

Avatar

Rama Suresh

Washington University in St. Louis

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Benjamin R. Tan

Washington University in St. Louis

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Foluso O. Ademuyiwa

Washington University in St. Louis

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Jingqin Luo

Washington University in St. Louis

View shared research outputs
Researchain Logo
Decentralizing Knowledge