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174
result(s) for
"Myers, Jeffrey N."
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Deep learning‐based pathology image analysis predicts cancer progression risk in patients with oral leukoplakia
by
Gomez, Ricardo Santiago
,
Williams, Michelle
,
Zhang, Xinyi
in
Algorithms
,
Biopsy
,
carcinogenesis
2023
Background Oral leukoplakia (OL) is associated with an increased risk for oral cancer (OC) development. Prediction of OL cancer progression may contribute to decreased OC morbidity and mortality by favoring early intervention. Current OL progression risk assessment approaches face large interobserver variability and is weakly prognostic. We hypothesized that convolutional neural networks (CNN)‐based histology image analyses could accelerate the discovery of better OC progression risk models. Methods Our CNN‐based oral mucosa risk stratification model (OMRS) was trained to classify a set of nondysplastic oral mucosa (OM) and a set of OC H&E slides. As a result, the OMRS model could identify abnormal morphological features of the oral epithelium. By applying this model to OL slides, we hypothesized that the extent of OC‐like features identified in the OL epithelium would correlate with its progression risk. The OMRS model scored and categorized the OL cohort (n = 62) into high‐ and low‐risk groups. Results OL patients classified as high‐risk (n = 31) were 3.98 (95% CI 1.36–11.7) times more likely to develop OC than low‐risk ones (n = 31). Time‐to‐progression significantly differed between high‐ and low‐risk groups (p = 0.003). The 5‐year OC development probability was 21.3% for low‐risk and 52.5% for high‐risk patients. The predictive power of the OMRS model was sustained even after adjustment for age, OL site, and OL dysplasia grading (HR = 4.52, 1.5–13.7). Conclusion The ORMS model successfully identified OL patients with a high risk of OC development and can potentially benefit OC early diagnosis and prevention policies. We developed a deep learning image analysis model using a convolutional neural network to predict the risk of oral cancer development from whole slide images in a patient with oral leukoplakia. The model successfully discriminated patients into two groups with distinct risk for oral cancer development, which represents a potential ancillary tool for the management of oral leukoplakia and may contribute to the early detection and treatment of oral cancer.
Journal Article
Loss of p53 drives neuron reprogramming in head and neck cancer
2020
The solid tumour microenvironment includes nerve fibres that arise from the peripheral nervous system
1
,
2
. Recent work indicates that newly formed adrenergic nerve fibres promote tumour growth, but the origin of these nerves and the mechanism of their inception are unknown
1
,
3
. Here, by comparing the transcriptomes of cancer-associated trigeminal sensory neurons with those of endogenous neurons in mouse models of oral cancer, we identified an adrenergic differentiation signature. We show that loss of
TP53
leads to adrenergic transdifferentiation of tumour-associated sensory nerves through loss of the microRNA miR-34a. Tumour growth was inhibited by sensory denervation or pharmacological blockade of adrenergic receptors, but not by chemical sympathectomy of pre-existing adrenergic nerves. A retrospective analysis of samples from oral cancer revealed that p53 status was associated with nerve density, which was in turn associated with poor clinical outcomes. This crosstalk between cancer cells and neurons represents mechanism by which tumour-associated neurons are reprogrammed towards an adrenergic phenotype that can stimulate tumour progression, and is a potential target for anticancer therapy.
MicroRNAs from head and neck cancer cells, shuttled to sensory neurons by extracellular vesicles, cause a shift to an adrenergic neuronal phenotype that promotes tumour progression.
Journal Article
Molecular jackhammers eradicate cancer cells by vibronic-driven action
by
Corona, Arnoldo
,
Myers, Jeffrey N.
,
Galvez-Aranda, Diego
in
631/154/309/2420
,
639/638/309/2144
,
Actuation
2024
Through the actuation of vibronic modes in cell-membrane-associated aminocyanines, using near-infrared light, a distinct type of molecular mechanical action can be exploited to rapidly kill cells by necrosis. Vibronic-driven action (VDA) is distinct from both photodynamic therapy and photothermal therapy as its mechanical effect on the cell membrane is not abrogated by inhibitors of reactive oxygen species and it does not induce thermal killing. Subpicosecond concerted whole-molecule vibrations of VDA-induced mechanical disruption can be achieved using very low concentrations (500 nM) of aminocyanines or low doses of light (12 J cm
−2
, 80 mW cm
−2
for 2.5 min), resulting in complete eradication of human melanoma cells in vitro. Also, 50% tumour-free efficacy in mouse models for melanoma was achieved. The molecules that destroy cell membranes through VDA have been termed molecular jackhammers because they undergo concerted whole-molecule vibrations. Given that a cell is unlikely to develop resistance to such molecular mechanical forces, molecular jackhammers present an alternative modality for inducing cancer cell death.
In contrast to photothermal therapy requiring high powers over extended times and photodynamic therapy being abrogated by inhibitors of reactive oxygen species, actuation of vibronic modes in single molecules—molecular jackhammers—can now induce efficient cancer cell death. Here, the mechanical disassembly of cell membranes is characterized as the underlying mechanism by which this vibronic-driven action promotes necrotic cell death.
Journal Article
Mutant p53 gains oncogenic functions through a chromosomal instability-induced cytosolic DNA response
2024
Inactivating
TP53
mutations leads to a loss of function of p53, but can also often result in oncogenic gain-of-function (GOF) of mutant p53 (mutp53) proteins which promotes tumor development and progression. The GOF activities of
TP53
mutations are well documented, but the mechanisms involved remain poorly understood. Here, we study the mutp53 interactome and find that by targeting minichromosome maintenance complex components (MCMs), GOF mutp53 predisposes cells to replication stress and chromosomal instability (CIN), leading to a tumor cell-autonomous and cyclic GMP–AMP synthase (cGAS)-stimulator of interferon genes (STING)-dependent cytosolic DNA response that activates downstream non-canonical nuclear factor kappa light chain enhancer of activated B cell (NC-NF-κB) signaling. Consequently, GOF mutp53-MCMs-CIN-cytosolic DNA-cGAS-STING-NC-NF-κB signaling promotes tumor cell metastasis and an immunosuppressive tumor microenvironment through antagonizing interferon signaling and regulating genes associated with pro-tumorigenic inflammation. Our findings have important implications for understanding not only the GOF activities of
TP53
mutations but also the genome-guardian role of p53 and its inactivation during tumor development and progression.
Here the authors show that gain-of-function mutant p53s predispose cells to chromosomal instability by targeting MCMs, leading to activation of a cGAS-STING-non-canonical NF-κB signaling that promotes tumor metastasis and immunosuppression.
Journal Article
STAT3 Oligonucleotide Inhibits Tumor Angiogenesis in Preclinical Models of Squamous Cell Carcinoma
2014
Signal transducer and activator of transcription 3 (STAT3) has shown to play a critical role in head and neck squamous cell carcinoma (HNSCC) and we have recently completed clinical trials of STAT3 decoy oligonucleotide in patients with recurrent or metastatic HNSCC. However, there is limited understanding of the role of STAT3 in modulating other aspects of tumorigenesis such as angiogenesis. In this study, we aimed to examine the effects of STAT3 decoy oligonucleotide on tumor angiogenesis.
A STAT3 decoy oligonucleotide and small interfering RNA (siRNA) were used to inhibit STAT3 in endothelial cells in vitro and in vivo. The biochemical effects of STAT3 inhibition were examined in conjunction with the consequences on proliferation, migration, apoptotic staining, and tubule formation. Additionally, we assessed the effects of STAT3 inhibition on tumor angiogenesis using murine xenograft models.
STAT3 decoy oligonucleotide decreased proliferation, induces apoptosis, decreased migration, and decreased tubule formation of endothelial cells in vitro. The STAT3 decoy oligonucleotide also inhibited tumor angiogenesis in murine tumor xenografts. Lastly, our data suggest that the antiangiogenic effects of STAT3 decoy oligonucleotide were mediatedthrough the inhibition of both STAT3 and STAT1.
The STAT3 decoy oligonucleotidewas found to be an effective antiangiogenic agent, which is likely to contribute to the overall antitumor effects of this agent in solid tumors.Taken together with the previously demonstrated antitumor activity of this agent, STAT3 decoy oligonucleotide represents a promising single agent approach to targeting both the tumor and vascular compartments in various malignancies.
Journal Article
Cross-species identification of genomic drivers of squamous cell carcinoma development across preneoplastic intermediates
2016
Cutaneous squamous cell carcinoma (cuSCC) comprises 15–20% of all skin cancers, accounting for over 700,000 cases in USA annually. Most cuSCC arise in association with a distinct precancerous lesion, the actinic keratosis (AK). To identify potential targets for molecularly targeted chemoprevention, here we perform integrated cross-species genomic analysis of cuSCC development through the preneoplastic AK stage using matched human samples and a solar ultraviolet radiation-driven Hairless mouse model. We identify the major transcriptional drivers of this progression sequence, showing that the key genomic changes in cuSCC development occur in the normal skin to AK transition. Our data validate the use of this ultraviolet radiation-driven mouse cuSCC model for cross-species analysis and demonstrate that cuSCC bears deep molecular similarities to multiple carcinogen-driven SCCs from diverse sites, suggesting that cuSCC may serve as an effective, accessible model for multiple SCC types and that common treatment and prevention strategies may be feasible.
Cutaneous squamous cell of the skin is a common neoplasm that frequently arises from precancerous actinic keratoses. Here, the authors carry out genomic analysis on matched sets of human lesions and compare with those in ultraviolet treated mice and identify conserved drivers of tumour development.
Journal Article
Differential regulation of the REGγ–proteasome pathway by p53/TGF-β signalling and mutant p53 in cancer cells
Proteasome activity is frequently enhanced in cancer to accelerate metastasis and tumorigenesis. REGγ, a proteasome activator known to promote p53/p21/p16 degradation, is often overexpressed in cancer cells. Here we show that p53/TGF-β signalling inhibits the REGγ–20S proteasome pathway by repressing REGγ expression. Smad3 and p53 interact on the REGγ promoter via the p53RE/SBE region. Conversely, mutant p53 binds to the REGγ promoter and recruits p300. Importantly, mutant p53 prevents Smad3/N-CoR complex formation on the REGγ promoter, which enhances the activity of the REGγ–20S proteasome pathway and contributes to mutant p53 gain of function. Depletion of REGγ alters the cellular response to p53/TGF-β signalling in drug resistance, proliferation, cell cycle progression and proteasome activity. Moreover, p53 mutations show a positive correlation with REGγ expression in cancer samples. These findings suggest that targeting REGγ–20S proteasome for cancer therapy may be applicable to human tumours with abnormal p53/Smad protein status. Furthermore, this study demonstrates a link between p53/TGF-β signalling and the REGγ–20S proteasome pathway, and provides insight into the REGγ/p53 feedback loop.
REGγ is a proteasome activator and is frequently overexpressed in cancer cells. Here Ali
et al
. demonstrate that p53/TGF-β signalling inhibits REGγ expression, whereas p53 mutations increase REGγ transcription, identifying a gain of function for mutant p53.
Journal Article
Gain-of-function mutant p53 promotes the oncogenic potential of head and neck squamous cell carcinoma cells by targeting the transcription factors FOXO3a and FOXM1
by
Patel, Ameeta A.
,
Takahashi, Hideaki
,
Tanaka, Noriaki
in
631/67/1536
,
631/80/86
,
Amino Acid Substitution - genetics
2018
Many mutant p53 proteins exert oncogenic gain-of-function (GOF) properties that promote cancer cell invasive growth and metastasis, yet the mechanisms mediating these functions still largely remain elusive. We show here that overexpression of the GOF mutant p53 G245D and other GOF p53 mutants enhances the invasive cell growth of p53-deficient head and neck squamous cell carcinoma (HNSCC) UM-SCC-1 cells both in in vitro three-dimensional culture and in an in vivo orthotopic nude mouse model of HNSCC through a novel transcription-independent mechanism. We demonstrate that the expression of the oncogenic forkhead transcription factor
FOXM1
is upregulated by GOF mutant p53s. Moreover, we show that overexpression of GOF mutant p53 G245D decreases the AMP-activated protein kinase (AMPK)-mediated phosphorylation of FOXO3a, a tumor suppressive forkhead transcription factor, leading to its cytoplasmic accumulation. This downregulation of FOXO3a’s activity, in turn, leads to de-repression of
FOXM1
expression. Importantly, we show that either overexpression of
FOXO3a
or downregulation of
FOXM1
impairs both GOF mutant p53-mediated cell invasion in vitro and pulmonary metastases of UM-SCC-1 cells in vivo. Finally, not only do oral cancer patients with p53 mutations exhibit higher levels of
FOXM1
expression than patients with wild-type p53, but also HNSCC patients with
TP53
mutations and high levels of
FOXM1
expression have the poorest survival outcomes. Given our prior demonstration that GOF mutant p53s inhibit AMPK, our current study, establishes and demonstrates a novel transcription-independent GOF mutant p53-AMPK-FOXO3a-FOXM1 signaling cascade that plays an important role in mediating mutant p53s’ gain-of-function activities in HNSCCs.
Journal Article
Inhibition of histone acetyltransferase function radiosensitizes CREBBP/EP300 mutants via repression of homologous recombination, potentially targeting a gain of function
2021
Despite radiation forming the curative backbone of over 50% of malignancies, there are no genomically-driven radiosensitizers for clinical use. Herein we perform in vivo shRNA screening to identify targets generally associated with radiation response as well as those exhibiting a genomic dependency. This identifies the histone acetyltransferases
CREBBP
/
EP300
as a target for radiosensitization in combination with radiation in cognate mutant tumors. Further in vitro and in vivo studies confirm this phenomenon to be due to repression of homologous recombination following DNA damage and reproducible using chemical inhibition of histone acetyltransferase (HAT), but not bromodomain function. Selected mutations in
CREBBP
lead to a hyperacetylated state that increases CBP and BRCA1 acetylation, representing a gain of function targeted by HAT inhibition. Additionally, mutations in
CREBBP
/
EP300
are associated with recurrence following radiation in squamous cell carcinoma cohorts. These findings provide both a mechanism of resistance and the potential for genomically-driven treatment.
Mutations in histone acetyltransferases (HATs) CREBBP and EP300 are generally thought to lead to decreased function or absence of protein product. Here the authors describe a gain of function of several CREBBP mutations leading to baseline hyper-acetylation, increased homologous recombination and potential synergy between radiation and HAT inhibition in CREBBP/EP300 mutant tumors.
Journal Article
APOBEC3A is an oral cancer prognostic biomarker in Taiwanese carriers of an APOBEC deletion polymorphism
2017
Oral squamous cell carcinoma is a prominent cancer worldwide, particularly in Taiwan. By integrating omics analyses in 50 matched samples, we uncover in Taiwanese patients a predominant mutation signature associated with cytidine deaminase APOBEC, which correlates with the upregulation of
APOBEC3A
expression in the
APOBEC3
gene cluster at 22q13.
APOBEC3A
expression is significantly higher in tumors carrying
APOBEC3B-
deletion allele(s). High-level
APOBEC3A
expression is associated with better overall survival, especially among patients carrying
APOBEC3B
-deletion alleles, as examined in a second cohort (
n
= 188;
p
= 0.004). The frequency of
APOBEC3B
-deletion alleles is ~50% in 143 genotyped oral squamous cell carcinoma -Taiwan samples (27
A3B
−/−
:89
A3B
+/−
:27
A3B
+/+
), compared to the 5.8% found in 314 OSCC-TCGA samples. We thus report a frequent APOBEC mutational profile, which relates to a
APOBEC3B
-deletion germline polymorphism in Taiwanese oral squamous cell carcinoma that impacts expression of
APOBEC3A
, and is shown to be of clinical prognostic relevance. Our finding might be recapitulated by genomic studies in other cancer types.
Oral squamous cell carcinoma is a prevalent malignancy in Taiwan. Here, the authors show that OSCC in Taiwanese show a frequent deletion polymorphism in the cytidine deaminases gene cluster
APOBEC3
resulting in increased expression of A3A, which is shown to be of clinical prognostic relevance.
Journal Article