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"Le, Thanh T."
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Understanding and modeling nerve–cancer interactions
2023
The peripheral nervous system plays an important role in cancer progression. Studies in multiple cancer types have shown that higher intratumoral nerve density is associated with poor outcomes. Peripheral nerves have been shown to directly regulate tumor cell properties, such as growth and metastasis, as well as affect the local environment by modulating angiogenesis and the immune system. In this Review, we discuss the identity of nerves in organs in the periphery where solid tumors grow, the known mechanisms by which nerve density increases in tumors, and the effects these nerves have on cancer progression. We also discuss the strengths and weaknesses of current in vitro and in vivo models used to study nerve–cancer interactions. Increased understanding of the mechanisms by which nerves impact tumor progression and the development of new approaches to study nerve–cancer interactions will facilitate the discovery of novel treatment strategies to treat cancer by targeting nerves.
Journal Article
Purinergic Signaling in Pulmonary Inflammation
by
Harting, Matthew T.
,
Le, Thanh-Thuy T.
,
Li, Xiangyun
in
acute pulmonary inflammation
,
adenosine
,
Adenosine deaminase
2019
Purine nucleotides and nucleosides are at the center of biologic reactions. In particular, adenosine triphosphate (ATP) is the fundamental energy currency of cellular activity and adenosine has been demonstrated to play essential roles in human physiology and pathophysiology. In this review, we examine the role of purinergic signaling in acute and chronic pulmonary inflammation, with emphasis on ATP and adenosine. ATP is released into extracellular space in response to cellular injury and necrosis. It is then metabolized to adenosine monophosphate (AMP) via ectonucleoside triphosphate diphosphohydrolase-1 (CD39) and further hydrolyzed to adenosine via ecto-5'-nucleotidase (CD73). Adenosine signals via one of four adenosine receptors to exert pro- or anti-inflammatory effects. Adenosine signaling is terminated by intracellular transport by concentrative or equilibrative nucleoside transporters (CNTs and ENTs), deamination to inosine by adenosine deaminase (ADA), or phosphorylation back into AMP via adenosine kinase (AK). Pulmonary inflammatory and hypoxic conditions lead to increased extracellular ATP, adenosine diphosphate (ADP) and adenosine levels, which translates to increased adenosine signaling. Adenosine signaling is central to the pulmonary injury response, leading to various effects on inflammation, repair and remodeling processes that are either tissue-protective or tissue destructive. In the acute setting, particularly through activation of adenosine 2A and 2B receptors, adenosine signaling serves an anti-inflammatory, tissue-protective role. However, excessive adenosine signaling in the chronic setting promotes pro-inflammatory, tissue destructive effects in chronic pulmonary inflammation.
Journal Article
Cell morphology best predicts tumorigenicity and metastasis in vivo across multiple TNBC cell lines of different metastatic potential
by
Parker, Savannah R.
,
Conner, Sydney J.
,
Guarin, Justinne R.
in
Adhesion
,
Animal models
,
Animals
2024
Background
Metastasis is the leading cause of death in breast cancer patients. For metastasis to occur, tumor cells must invade locally, intravasate, and colonize distant tissues and organs, all steps that require tumor cell migration. The majority of studies on invasion and metastasis rely on human breast cancer cell lines. While it is known that these cells have different properties and abilities for growth and metastasis, the in vitro morphological, proliferative, migratory, and invasive behavior of these cell lines and their correlation to in vivo behavior is poorly understood. Thus, we sought to classify each cell line as poorly or highly metastatic by characterizing tumor growth and metastasis in a murine model of six commonly used human triple-negative breast cancer xenografts, as well as determine which in vitro assays commonly used to study cell motility best predict in vivo metastasis.
Methods
We evaluated the liver and lung metastasis of human TNBC cell lines MDA-MB-231, MDA-MB-468, BT549, Hs578T, BT20, and SUM159 in immunocompromised mice. We characterized each cell line's cell morphology, proliferation, and motility in 2D and 3D to determine the variation in these parameters between cell lines.
Results
We identified MDA-MB-231, MDA-MB-468, and BT549 cells as highly tumorigenic and metastatic, Hs578T as poorly tumorigenic and metastatic, BT20 as intermediate tumorigenic with poor metastasis to the lungs but highly metastatic to the livers, and SUM159 as intermediate tumorigenic but poorly metastatic to the lungs and livers. We showed that metrics that characterize cell morphology are the most predictive of tumor growth and metastatic potential to the lungs and liver. Further, we found that no single in vitro motility assay in 2D or 3D significantly correlated with metastasis in vivo
.
Conclusions
Our results provide an important resource for the TNBC research community, identifying the metastatic potential of 6 commonly used cell lines. Our findings also support the use of cell morphological analysis to investigate the metastatic potential and emphasize the need for multiple in vitro motility metrics using multiple cell lines to represent the heterogeneity of metastasis in vivo.
Journal Article
Synthetic prions with novel strain-specified properties
by
Legname, Giuseppe
,
Palamara, Luisa
,
T. Le, Thanh-Nhat
in
Amino Acid Sequence
,
Amyloidogenic Proteins - chemistry
,
Animals
2015
Prions are infectious proteins that possess multiple self-propagating structures. The information for strains and structural specific barriers appears to be contained exclusively in the folding of the pathological isoform, PrP(Sc). Many recent studies determined that de novo prion strains could be generated in vitro from the structural conversion of recombinant (rec) prion protein (PrP) into amyloidal structures. Our aim was to elucidate the conformational diversity of pathological recPrP amyloids and their biological activities, as well as to gain novel insights in characterizing molecular events involved in mammalian prion conversion and propagation. To this end we generated infectious materials that possess different conformational structures. Our methodology for the prion conversion of recPrP required only purified rec full-length mouse (Mo) PrP and common chemicals. Neither infected brain extracts nor amplified PrP(Sc) were used. Following two different in vitro protocols recMoPrP converted to amyloid fibrils without any seeding factor. Mouse hypothalamic GT1 and neuroblastoma N2a cell lines were infected with these amyloid preparations as fast screening methodology to characterize the infectious materials. Remarkably, a large number of amyloid preparations were able to induce the conformational change of endogenous PrPC to harbor several distinctive proteinase-resistant PrP forms. One such preparation was characterized in vivo habouring a synthetic prion with novel strain specified neuropathological and biochemical properties.
Journal Article
Sensory nerves enhance triple-negative breast cancer invasion and metastasis via the axon guidance molecule PlexinB3
by
Hayes, Lily A
,
Parker, Savannah R
,
Burge, Christopher B
in
Breast cancer
,
Cell adhesion & migration
,
Dopamine
2022
In breast cancer, nerve presence has been correlated with more invasive disease and worse prognosis, yet the mechanisms by which different types of peripheral nerves drive tumor progression remain poorly understood. In this study, we identified sensory nerves as more abundant in human triple-negative breast cancer (TNBC) tumors. Co-injection of sensory neurons isolated from the dorsal root ganglia (DRG) of adult female mice with human TNBC cells in immunocompromised mice increased the number of lung metastases. Direct in vitro co-culture of human TNBC cells with the dorsal root ganglia (DRG) of adult female mice revealed that TNBC cells adhere to sensory neuron fibers leading to an increase in migration speed. Species-specific RNA sequencing revealed that co-culture of TNBC cells with sensory nerves upregulates the expression of genes associated with cell migration and adhesion in cancer cells. We demonstrated that lack of the semaphorin receptor PlexinB3 in cancer cells attenuate their adhesion to and migration on sensory nerves. Together, our results identify a mechanism by which nerves contribute to breast cancer migration and metastasis by inducing a shift in TNBC cell gene expression and support the rationale for disrupting neuron-cancer cell interactions to target metastasis.
Journal Article
Conquering hypertension in Vietnam—solutions at grassroots level: study protocol of a cluster randomized controlled trial
2020
Background
Vietnam has been experiencing an epidemiologic transition to that of a lower-middle income country with an increasing prevalence of non-communicable diseases. The key risk factors for cardiovascular disease (CVD) are either on the rise or at alarming levels in Vietnam, particularly hypertension (HTN). Inasmuch, the burden of CVD will continue to increase in the Vietnamese population unless effective prevention and control measures are put in place. The objectives of the proposed project are to evaluate the implementation and effectiveness of two multi-faceted community and clinic-based strategies on the control of elevated blood pressure (BP) among adults in Vietnam via a cluster randomized trial design.
Methods
Sixteen communities will be randomized to either an intervention (8 communities) or a comparison group (8 communities). Eligible and consenting adult study participants with HTN (
n
= 680) will be assigned to intervention/comparison status based on the community in which they reside. Both comparison and intervention groups will receive a multi-level intervention modeled after the Vietnam National Hypertension Program including education and practice change modules for health care providers, accessible reading materials for patients, and a multi-media community awareness program.
In addition, the intervention group only will receive three carefully selected enhancements integrated into routine clinical care: (1) expanded community health worker services, (2) home BP self-monitoring, and (3) a “storytelling intervention,” which consists of interactive, literacy-appropriate, and culturally sensitive multi-media storytelling modules for motivating behavior change through the power of patients speaking in their own voices. The storytelling intervention will be delivered by DVDs with serial installments at baseline and at 3, 6, and 9 months after trial enrollment. Changes in BP will be assessed in both groups at several follow-up time points. Implementation outcomes will be assessed as well.
Discussion
Results from this full-scale trial will provide health policymakers with practical evidence on how to combat a key risk factor for CVD using a feasible, sustainable, and cost-effective intervention that could be used as a national program for controlling HTN in Vietnam.
Trial registration
ClinicalTrials.gov
NCT03590691
. Registered on July 17, 2018. Protocol version: 6. Date: August 15, 2019.
Journal Article
Plastin 3 Expression Does Not Modify Spinal Muscular Atrophy Severity in the ∆7 SMA Mouse
2015
Spinal muscular atrophy is caused by loss of the SMN1 gene and retention of SMN2. The SMN2 copy number inversely correlates with phenotypic severity and is a modifier of disease outcome. The SMN2 gene essentially differs from SMN1 by a single nucleotide in exon 7 that modulates the incorporation of exon 7 into the final SMN transcript. The majority of the SMN2 transcripts lack exon 7 and this leads to a SMN protein that does not effectively oligomerize and is rapidly degraded. However the SMN2 gene does produce some full-length SMN and the SMN2 copy number along with how much full-length SMN the SMN2 gene makes correlates with severity of the SMA phenotype. However there are a number of discordant SMA siblings that have identical haplotypes and SMN2 copy number yet one has a milder form of SMA. It has been suggested that Plastin3 (PLS3) acts as a sex specific phenotypic modifier where increased expression of PLS3 modifies the SMA phenotype in females. To test the effect of PLS3 overexpression we have over expressed full-length PLS3 in SMA mice. To ensure no disruption of functionality or post-translational processing of PLS3 we did not place a tag on the protein. PLS3 protein was expressed under the Prion promoter as we have shown previously that SMN expression under this promoter can rescue SMA mice. High levels of PLS3 mRNA were expressed in motor neurons along with an increased level of PLS3 protein in total spinal cord, yet there was no significant beneficial effect on the phenotype of SMA mice. Specifically, neither survival nor the fundamental electrophysiological aspects of the neuromuscular junction were improved upon overexpression of PLS3 in neurons.
Journal Article
Virological characterization of influenza H1N1pdm09 in Vietnam, 2010‐2013
2015
Objectives Influenza A/H1N1pdm09 virus was first detected in Vietnam on May 31, 2009, and continues to circulate in Vietnam as a seasonal influenza virus. This study has monitored genotypic and phenotypic changes in this group of viruses during 2010–2013 period. Design and setting We sequenced hemagglutinin (HA) and neuraminidase (NA) genes from representative influenza A/H1N1pdm09 and compared with vaccine strain A/California/07/09 and other contemporary isolates from neighboring countries. Hemagglutination inhibition (HI) and neuraminidase inhibition (NAI) assays also were performed on these isolates. Sample Representative influenza A/H1N1pdm09 isolates (n = 61) from ILI and SARI surveillances in northern Vietnam between 2010 and 2013. Main outcome measures and results The HA and NA phylogenies revealed six and seven groups, respectively. Five isolates (8·2%) had substitutions G155E and N156K in the HA, which were associated with reduced HI titers by antiserum raised against the vaccine virus A/California/07/2009. One isolate from 2011 and one isolate from 2013 had a predicted H275Y substitution in the neuraminidase molecule, which was associated with reduced susceptibility to oseltamivir in a NAI assay. We also identified a D222N change in the HA of a virus isolated from a fatal case in 2013. Conclusions Significant genotypic and phenotypic changes in A/ H1N1pdm09 influenza viruses were detected by the National Influenza Surveillance System (NISS) in Vietnam between 2010 and 2013 highlighting the value of this system to Vietnam and to the region. Sustained NISS and continued virological monitoring of seasonal influenza viruses are required for vaccine policy development in Vietnam. 3
Journal Article
Rescue of the spinal muscular atrophy phenotype in a mouse model by early postnatal delivery of SMN
by
FOUST, Kevin D
,
XUEYONG WANG
,
HAIDET, Amanda M
in
Adeno-associated virus
,
Animals
,
Animals, Newborn
2010
Spinal muscular atrophy (SMA), the most common autosomal recessive neurodegenerative disease affecting children, results in impaired motor neuron function. Despite knowledge of the pathogenic role of decreased survival motor neuron (SMN) protein levels, efforts to increase SMN have not resulted in a treatment for patients. We recently demonstrated that self-complementary adeno-associated virus 9 (scAAV9) can infect approximately 60% of motor neurons when injected intravenously into neonatal mice. Here we use scAAV9-mediated postnatal day 1 vascular gene delivery to replace SMN in SMA pups and rescue motor function, neuromuscular physiology and life span. Treatment on postnatal day 5 results in partial correction, whereas postnatal day 10 treatment has little effect, suggesting a developmental period in which scAAV9 therapy has maximal benefit. Notably, we also show extensive scAAV9-mediated motor neuron transduction after injection into a newborn cynomolgus macaque. This demonstration that scAAV9 traverses the blood-brain barrier in a nonhuman primate emphasizes the clinical potential of scAAV9 gene therapy for SMA.
Journal Article