Ashish Kumar

Dr. Ashish Kumar

Department of Cancer Biology, Atrium Health Wake Forest Baptist Medical Center, Winston-Salem, NC 27157, USA

Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

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

Representative Publications

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15 December 2021 in Cancers
Verified
Journal Article
Open access
PDF file
Leslimar Rios-ColonLeslimar Rios-Colon
Leslimar Rios-Colon
PKPawan Kumar
Pawan Kumar
SKSusy Kim
Susy Kim
MSMitu Sharma
Mitu Sharma
YSYIXIN SU
YIXIN SU
Gagan DeepGagan Deep
Gagan Deep
Hypoxia and hypoxia-related biomarkers are the major determinants of prostate cancer (PCa) aggressiveness. Therefore, a better understanding of molecular players involved in PCa cell survival under hypoxia could offer novel therapeutic targets. We previously reported a central role of mitochondrial protein carnitine palmitoyltransferase (CPT1A) in PCa progression, but its role in regulating PCa survival under hypoxia remains unknown. Here, we employed PCa cells (22Rv1 and MDA-PCa-2b) with knockdown or overexpression of CPT1A and assessed their survival under hypoxia, both in cell culture and in vivo models. The results showed that CPT1A knockdown in PCa cells significantly reduced their viability, clonogenicity, and sphere formation under hypoxia, while its overexpression increased their proliferation, clonogenicity, and sphere formation. In nude mice, 22Rv1 xenografts with CPT1A knockdown grew significantly slower compared to vector control cells (~59% reduction in tumor volume at day 29). On the contrary, CPT1A-overexpressing 22Rv1 xenografts showed higher tumor growth compared to vector control cells (~58% higher tumor volume at day 40). Pathological analyses revealed lesser necrotic areas in CPT1A knockdown tumors and higher necrotic areas in CPT1A overexpressing tumors. Immunofluorescence analysis of tumors showed that CPT1A knockdown strongly compromised the hypoxic areas (pimonidazole+), while CPT1A overexpression resulted in more hypoxia areas with strong expression of proliferation biomarkers (Ki67 and cyclin D1). Finally, IHC analysis of tumors revealed a significant decrease in VEGF or VEGF-D expression but without significant changes in biomarkers associated with microvessel density. These results suggest that CPT1A regulates PCa survival in hypoxic conditions and might contribute to their aggressiveness.

28 March 2022 in Biomolecules
Verified
Journal Article
Open access
PDF file
HRHilal Ahmad Rather
Hilal Ahmad Rather
SMShalini Mishra
Shalini Mishra
YSYIXIN SU
YIXIN SU
AKAshish Kumar
Ashish Kumar
SSSangeeta Singh
Sangeeta Singh
Gagan DeepGagan Deep
Gagan Deep
Cocaine use disorder has been reported to cause transgenerational effects. However, due to the lack of standardized biomarkers, the effects of cocaine use during pregnancy on postnatal development and long-term neurobiological and behavioral outcomes have not been investigated thoroughly. Therefore, in this study, we examined extracellular vesicles (EVs) in adult (~12 years old) female and male rhesus monkeys prenatally exposed to cocaine (n = 11) and controls (n = 9). EVs were isolated from the cerebrospinal fluid (CSF) and characterized for the surface expression of specific tetraspanins, concentration (particles/mL), size distribution, and cargo proteins by mass spectrometry (MS). Transmission electron microscopy following immunogold labeling for tetraspanins (CD63, CD9, and CD81) confirmed the successful isolation of EVs. Nanoparticle tracking analyses showed that the majority of the particles were <200 nm in size, suggesting an enrichment for small EVs (sEV). Interestingly, the prenatally cocaine-exposed group showed ~54% less EV concentration in CSF compared to the control group. For each group, MS analyses identified a number of proteins loaded in CSF-EVs, many of which are commonly listed in the ExoCarta database. Ingenuity pathway analysis (IPA) demonstrated the association of cargo EV proteins with canonical pathways, diseases and disorders, upstream regulators, and top enriched network. Lastly, significantly altered proteins between groups were similarly characterized by IPA, suggesting that prenatal cocaine exposure could be potentially associated with long-term neuroinflammation and risk for neurodegenerative diseases. Overall, these results indicate that CSF-EVs could potentially serve as biomarkers to assess the transgenerational adverse effects due to prenatal cocaine exposure.

19 December 2023 in Cancers
Verified
Journal Article
Open access
PDF file
HRHilal Ahmad Rather
Hilal Ahmad Rather
SASameh Almousa
Sameh Almousa
AKAshish Kumar
Ashish Kumar
MSMitu Sharma
Mitu Sharma
IPIsabel Pennington
Isabel Pennington
Gagan DeepGagan Deep
Gagan Deep
Recent studies have demonstrated the association of APP and Aβ with cancer, suggesting that BACE1 may play an important role in carcinogenesis. In the present study, we assessed BACE1’s usefulness as a therapeutic target in prostate cancer (PCa). BACE1 expression was observed in human PCa tissue samples, patient-derived xenografts (PDX), human PCa xenograft tissue in nude mice, and transgenic adenocarcinoma of the mouse prostate (TRAMP) tissues by immunohistochemistry (IHC) analysis. Additionally, the downstream product of BACE1 activity, i.e., Aβ1-42 expression, was also observed in these PCa tissues by IHC as well as by PET imaging in TRAMP mice. Furthermore, BACE1 gene expression and activity was confirmed in several established PCa cell lines (LNCaP, C4-2B-enzalutamide sensitive [S], C4-2B-enzalutamide resistant [R], 22Rv1-S, 22Rv1-R, PC3, DU145, and TRAMP-C1) by real-time PCR and fluorometric assay, respectively. Treatment with a pharmacological inhibitor of BACE1 (MK-8931) strongly reduced the proliferation of PCa cells in in vitro and in vivo models, analyzed by multiple assays (MTT, clonogenic, and trypan blue exclusion assays and IHC). Cell cycle analyses revealed an increase in the sub-G1 population and a significant modulation in other cell cycle stages (G1/S/G2/M) following MK-8931 treatment. Most importantly, in vivo administration of MK-8931 intraperitoneal (30 mg/kg) strongly inhibited TRAMP-C1 allograft growth in immunocompetent C57BL/6 mice (approximately 81% decrease, p = 0.019). Furthermore, analysis of tumor tissue using the prostate cancer-specific pathway array revealed the alteration of several genes involved in PCa growth and progression including Forkhead O1 (FOXO1). All together, these findings suggest BACE1 as a novel therapeutic target in advanced PCa.

1 December 2024 in Alzheimer's & Dementia
Verified
Journal Article
Open access
AKAshish Kumar
Ashish Kumar
JCJacob Alexander Cleary
Jacob Alexander Cleary
YSYixin Su
Yixin Su
SSSangeeta Singh
Sangeeta Singh
MHMarjorie Howard
Marjorie Howard
GDGagan Deep
Gagan Deep
Background: Central nervous system (CNS) dysregulated insulin and peripheral hyperinsulinemia has been associated with AD. However, analyzing CNS insulin resistance in living subjects and its implication on cognitive impairment/ AD is difficult to establish due to inaccessibility of brain tissue. In this study we isolated and characterized plasma neuron‐derived small extracellular vesicles (NDE), and adopted multi‐omics approaches to discover novel biomarkers of AD and CNS insulin resistance and suggested their possible association.Method: Plasma samples were obtained from Look AHEAD‐MIND study with 28 cognitively normal (18 female and 10 male) and 28 individuals with probable dementia (11 female and 17 male) based on central adjudication by an expert panel. These individuals had established type 2 diabetes (T2D) and overweight/obesity when enrolled in a randomized controlled clinical trial of a 10‐year behavioral intervention. NDE were enriched from plasma sequentially using CD171 and synaptophysin surface markers by immunoprecipitation and characterized for non‐coding RNAs by small RNA‐sequencing and proteomics by mass spectrometry.Result: The small RNA‐sequencing analysis identified the expression of over 100 miRNAs in NDE from both groups. The Comparison of differentially expressed miRNAs revealed 42 miRNAs to be downregulated, while 23 miRNAs were upregulated in individuals with dementia. Importantly, all these miRNAs (both up‐ and –downregulated) were found to be over‐represented in AD‐ and insulin signaling‐related pathways. Also, the targets of these miRNAs were associated with pathways like protein phosphorylation, autophagy, cell cycle and nervous system development. Alongside, the mass spectrometry‐based proteomics analysis identified 3 proteins (haptoglobin, complement component C6, and alpha‐2‐macroglobulin) to be significantly downregulated and 1 protein (desmocolin‐1) to be upregulated in the NDE of individuals with dementia. Interestingly, NDE showed upregulated expression of miR‐185‐5p, with concomitant downregulation of one of its potential targets complement protein C6, both known to be associated with AD and insulin signaling.Conclusion: The study demonstrated multi‐omics approach to identify novel plasma NDE biomarkers for dementia pathogenesis and its association with CNS insulin resistance in individuals with T2D.

31 December 2021 in Alzheimer's & Dementia
Verified
Journal Article
Closed access
PDF file
AKAshish Kumar
Ashish Kumar
MSMitu Sharma
Mitu Sharma
SSSangeeta Singh
Sangeeta Singh
YSYixin Su
Yixin Su
FHFang‐Chi Hsu
Fang‐Chi Hsu
GDGagan Deep
Gagan Deep