Andrew Dhawan

Dr. Andrew Dhawan

orcid

Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 March 2023 in Journal of Clinical Oncology
Verified
Journal Article
Open access
Manmeet S AhluwaliaManmeet S Ahluwalia
Manmeet S Ahluwalia
DRDavid A. Reardon
David A. Reardon
AAAjay P. Abad
Ajay P. Abad
WCWilliam T. Curry
William T. Curry
EWEric T. Wong
Eric T. Wong
RFRobert A. Fenstermaker
Robert A. Fenstermaker
PURPOSE: Despite intensive treatment with surgery, radiation therapy, temozolomide (TMZ) chemotherapy, and tumor-treating fields, mortality of newly diagnosed glioblastoma (nGBM) remains very high. SurVaxM is a peptide vaccine conjugate that has been shown to activate the immune system against its target molecule survivin, which is highly expressed by glioblastoma cells. We conducted a phase IIa, open-label, multicenter trial evaluating the safety, immunologic effects, and survival of patients with nGBM receiving SurVaxM plus adjuvant TMZ following surgery and chemoradiation (ClinicalTrials.gov identifier: NCT02455557 ). METHODS: Sixty-four patients with resected nGBM were enrolled including 38 men and 26 women, in the age range of 20-82 years. Following craniotomy and fractionated radiation therapy with concurrent TMZ, patients received four doses of SurVaxM (500 μg once every 2 weeks) in Montanide ISA-51 plus sargramostim (granulocyte macrophage colony-stimulating factor) subcutaneously. Patients subsequently received adjuvant TMZ and maintenance SurVaxM concurrently until progression. Progression-free survival (PFS) and overall survival (OS) were reported. Immunologic responses to SurVaxM were assessed. RESULTS: SurVaxM plus TMZ was well tolerated with no serious adverse events attributable to SurVaxM. Of the 63 patients who were evaluable for outcome, 60 (95.2%) remained progression-free 6 months after diagnosis (prespecified primary end point). Median PFS was 11.4 months and median OS was 25.9 months measured from first dose of SurVaxM. SurVaxM produced survivin-specific CD8+ T cells and antibody/immunoglobulin G titers. Apparent clinical benefit of SurVaxM was observed in both methylated and unmethylated patients. CONCLUSION: SurVaxM appeared to be safe and well tolerated. The combination represents a promising therapy for nGBM. For patients with nGBM treated in this manner, PFS may be an acceptable surrogate for OS. A large randomized clinical trial of SurVaxM for nGBM is in progress.

7 March 2023 in Neurology
Verified
Journal Article
Closed access
PDF file
SLShreya Louis
Shreya Louis
ACAlise K. Carlson
Alise K. Carlson
ASAbhilash Suresh
Abhilash Suresh
JRJoshua Rim
Joshua Rim
MMMaryAnn Mays
MaryAnn Mays
ADAndrew Dhawan
Andrew Dhawan
Background and objectives: Although the international community collectively seeks to reduce global temperature rise to under 1.5ºC before 2100, irreversible environmental changes have already occurred, and as the planet warms these changes will continue to occur. As we witness the effects of a warming planet on human health, it is imperative that neurologists anticipate how the epidemiology and incidence of neurologic disease may change. In this review, we organized our analysis around three key themes related to climate change and neurologic health: extreme weather events and temperature fluctuations, emerging neuro-infectious diseases, and pollutant impacts. Across each of these themes, we appraised and reviewed recent literature relevant to neurological disease and practice. Methods: Studies were identified using search terms relating to climate change, pollutants, and neurologic disease in PubMed, OVID MEDLINE, Embase, PsycInfo, and grey literature. Studies published between 1990 and 2022 were included if they pertained to human incidence or prevalence of disease, were in English, and were relevant to neurologic disease. Results: We identified a total of 364 articles, grouped into the three key themes of our study; extreme weather events and temperature fluctuations (38 studies), emerging neuro-infectious diseases (37 studies), and pollutant impacts (289 studies). The included studies highlighted the relationships between neurologic symptom exacerbation and temperature variability, tick-borne infections and warming climates, and airborne pollutants and cerebrovascular disease incidence and severity. Discussion: Temperature extremes and variability both associated with stroke incidence and severity, migraine headaches, hospitalization in dementia patients, and multiple sclerosis exacerbations. Exposure to airborne pollutants, especially PM2.5 and nitrates, associated with stroke incidence and severity, headaches, dementia risk, Parkinson’s disease, and MS exacerbation. Climate change has demonstrably expanded favorable conditions for zoonotic diseases beyond traditional borders, and poses the risk of disease in new, susceptible populations. Articles were biased towards resource-rich regions, suggesting a discordance between where research occurs and where changes are most acute. As such, three key priorities emerged for further study; neuro-infectious disease risk mitigation, understanding the pathophysiology of airborne pollutants on the nervous system, and methods to improve delivery of neurologic care in the face of climate-related disruptions.

14 May 2020 in Nature Communications
Verified
Journal Article
Open access
PDF file
RVRobert Vander Velde
Robert Vander Velde
NYNara Yoon
Nara Yoon
VMViktoriya Marusyk
Viktoriya Marusyk
ADArda Durmaz
Arda Durmaz
ADAndrew Dhawan
Andrew Dhawan
AMAndriy Marusyk
Andriy Marusyk
Despite high initial efficacy, targeted therapies eventually fail in advanced cancers, as tumors develop resistance and relapse. In contrast to the substantial body of research on the molecular mechanisms of resistance, understanding of how resistance evolves remains limited. Using an experimental model of ALK positive NSCLC, we explored the evolution of resistance to different clinical ALK inhibitors. We found that resistance can originate from heterogeneous, weakly resistant subpopulations with variable sensitivity to different ALK inhibitors. Instead of the commonly assumed stochastic single hit (epi) mutational transition, or drug-induced reprogramming, we found evidence for a hybrid scenario involving the gradual, multifactorial adaptation to the inhibitors through acquisition of multiple cooperating genetic and epigenetic adaptive changes. Additionally, we found that during this adaptation tumor cells might present unique, temporally restricted collateral sensitivities, absent in therapy naïve or fully resistant cells, suggesting the potential for new therapeutic interventions, directed against evolving resistance.

7 December 2018 in Nature Communications
Verified
Journal Article
Open access
PDF file
ADAndrew Dhawan
Andrew Dhawan
JSJacob G Scott
Jacob G Scott
AHAdrian L. Harris
Adrian L. Harris
FBFrancesca Buffa
Francesca Buffa
MicroRNAs are key regulators of the human transcriptome across a number of diverse biological processes, such as development, aging and cancer, where particular miRNAs have been identified as tumour suppressive and oncogenic. In this work, we elucidate, in a comprehensive manner, across 15 epithelial cancer types comprising 7316 clinical samples from the Cancer Genome Atlas, the association of miRNA expression and target regulation with the phenotypic hallmarks of cancer. Utilising penalised regression techniques to integrate transcriptomic, methylation and mutation data, we find evidence for a complex map of interactions underlying the relationship of miRNA regulation and the hallmarks of cancer. This highlighted high redundancy for the oncomiR-1 cluster of oncogenic miRNAs, in particular hsa-miR-17-5p. In addition, we reveal extensive miRNA regulation of tumour suppressor genes such as PTEN, FAT4 and CDK12, uncovering an alternative mechanism of repression in the absence of mutation, methylation or copy number changes.

27 April 2017 in Scientific Reports
Verified
Journal Article
Open access
PDF file
ADAndrew Dhawan
Andrew Dhawan
DNDaniel Nichol
Daniel Nichol
FKFumi Kinose
Fumi Kinose
MAMohamed E. Abazeed
Mohamed E. Abazeed
AMAndriy Marusyk
Andriy Marusyk
JSJacob G Scott
Jacob G Scott
Drug resistance remains an elusive problem in cancer therapy, particularly for novel targeted therapies. Much work is focused upon the development of an arsenal of targeted therapies, towards oncogenic driver genes such as ALK-EML4, to overcome the inevitable resistance that develops over time. Currently, after failure of first line ALK TKI therapy, another ALK TKI is administered, though collateral sensitivity is not considered. To address this, we evolved resistance in an ALK rearranged non-small cell lung cancer line (H3122) to a panel of 4 ALK TKIs, and performed a collateral sensitivity analysis. All ALK inhibitor resistant cell lines displayed significant cross-resistance to all other ALK inhibitors. We then evaluated ALK-inhibitor sensitivities after drug holidays of varying length (1–21 days), and observed dynamic patterns of resistance. This unpredictability led us to an expanded search for treatment options, where we tested 6 further anti-cancer agents for collateral sensitivity among resistant cells, uncovering possibilities for further treatment, including cross-sensitivity to standard cytotoxic therapies, as well as Hsp90 inhibitors. Taken together, these results imply that resistance to targeted therapy in non-small cell lung cancer is highly dynamic, and also one where there are many opportunities to re-establish sensitivities where there was once resistance. Drug resistance in cancer inevitably emerges during treatment; particularly with novel targeted therapies, designed to inhibit specific molecules. A clinically-relevant example of this phenomenon occurs in ALK-positive non-small cell lung cancer, where targeted therapies are used to inhibit the ALK-EML4 fusion protein. A potential solution to this may lie in finding drug sensitivities in the resistant population, termed collateral sensitivities, and then using these as second-line agents. This study shows how the evolution of resistance in ALK-positive lung cancer is a dynamic process through time, one in which patterns of drug resistance and collateral sensitivity change substantially, and therefore one where temporal regimens, such as drug cycling and drug holidays may have great benefit.

20 August 2019 in Science Signaling
Verified
Journal Article
Closed access
PDF file
AGAaron Goldman
Aaron Goldman
SKSachin Khiste
Sachin Khiste
EFElizaveta Freinkman
Elizaveta Freinkman
ADAndrew Dhawan
Andrew Dhawan
BMBiswanath Majumder
Biswanath Majumder
SSShiladitya Sengupta
Shiladitya Sengupta
Metastable phenotypic state transitions in cancer cells can lead to the development of transient adaptive resistance or tolerance to chemotherapy. Here, we report that the acquisition of a phenotype marked by increased abundance of CD44 (CD44Hi) by breast cancer cells as a tolerance response to routinely used cytotoxic drugs, such as taxanes, activated a metabolic switch that conferred tolerance against unrelated standard-of-care chemotherapeutic agents, such as anthracyclines. We characterized the sequence of molecular events that connected the induced CD44Hi phenotype to increased activity of both the glycolytic and oxidative pathways and glucose flux through the pentose phosphate pathway (PPP). When given in a specific order, a combination of taxanes, anthracyclines, and inhibitors of glucose-6-phosphate dehydrogenase (G6PD), an enzyme involved in glucose metabolism, improved survival in mouse models of breast cancer. The same sequence of the three-drug combination reduced the viability of patient breast tumor samples in an explant system. Our findings highlight a convergence between phenotypic and metabolic state transitions that confers a survival advantage to cancer cells against clinically used drug combinations. Pharmacologically targeting this convergence could overcome cross-drug tolerance and could emerge as a new paradigm in the treatment of cancer.