γδ T cells are evolutionarily conserved T lymphocytes that manifest unique antitumor efficacy independent of tumor mutation burden (TMB) and conventional human leukocyte antigen (HLA) recognition. However, the dynamic changes in their T cell receptor (TCR) repertoire during cancer progression and treatment courses remain unclear. Here, a comprehensive characterization of γδTCR repertoires are performed in thyroid cancers with divergent differentiation states through cross-sectional studies.
View Article and Find Full Text PDFPurpose: Primary or acquired resistance to cetuximab, an antiepidermal growth factor receptor monoclonal antibody (mAb), minimizes its utility in recurrent/metastatic head and neck squamous cell carcinoma (HNSCC). Aberrant hepatocyte growth factor/cMet pathway activation is an established resistance mechanism. Dual pathway targeting may overcome resistance.
View Article and Find Full Text PDFAnaplastic thyroid cancer (ATC) is a rare but lethal malignancy with a dismal prognosis. There is an urgent need for more in-depth research on the carcinogenesis and development of ATC, as well as therapeutic methods, since standard treatments are essentially depleted in ATC patients. However, low prevalence has hampered thorough clinical studies and the collection of tissue samples, so little progress has been achieved in creating effective treatments.
View Article and Find Full Text PDFCancer-associated fibroblasts (CAFs) are the predominant components of the tumor microenvironment (TME) and influence cancer hallmarks, but without systematic investigation on their ubiquitous characteristics across different cancer types. Here, we perform pan-cancer analysis on 226 samples across 10 solid cancer types to profile the TME at single-cell resolution, illustrating the commonalities/plasticity of heterogenous CAFs. Activation trajectory of the major CAF types is divided into three states, exhibiting distinct interactions with other cell components, and relating to prognosis of immunotherapy.
View Article and Find Full Text PDFUnderstanding of dedifferentiation, an indicator of poo prognosis for patients with thyroid cancer, has been hampered by imprecise and incomplete characterization of its heterogeneity and its attributes. Using single-cell RNA sequencing, we explored the landscape of thyroid cancer at single-cell resolution with 46,205 cells and delineated its dedifferentiation process and suppressive immune microenvironment. The developmental trajectory indicated that anaplastic thyroid cancer (ATC) cells were derived from a small subset of papillary thyroid cancer (PTC) cells.
View Article and Find Full Text PDFCurr Treat Options Oncol
May 2021
To date, there is no FDA-approved chemoprevention approach for tobacco-related HNSCC. Effective chemoprevention approaches validated in sufficiently powered randomized trials are needed to reduce the incidence and improve survival. In this review, we recap the challenges encountered in past chemoprevention trials and discuss emerging approaches, with major focus on green chemoprevention, precision prevention, and immunoprevention.
View Article and Find Full Text PDFOral squamous cell carcinoma (OSCC) develops through the multistep malignant progression of squamous epithelium. This process can be prevented by PD-1 blockade in a mouse model for oral carcinogenesis. OSCCs exhibit a high incidence of mutations that confer oncogenic gain-of-function (GOF) activities that promote resistance to standard therapies and poor clinical outcomes.
View Article and Find Full Text PDFPurpose: Cancer susceptibility and mortality are higher in males, and the mutational and transcriptomic landscape of cancer differs by sex. The current assumption is that men are at higher risk of epithelial cancers as they expose more to carcinogens and accumulate more damage than women. We present data showing women present with less aggressive primary cutaneous squamous cell carcinoma (cSCC) and early strong immune activation.
View Article and Find Full Text PDFThe solid tumour microenvironment includes nerve fibres that arise from the peripheral nervous system. 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. 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.
View Article and Find Full Text PDFJ Invest Dermatol
June 2020
Skin homeostasis is controlled by a complex interplay between tightly regulated transcription factors and signaling pathways. MYB is a transcription factor expressed in hair follicle progenitor cells and found overexpressed in adnexal skin tumors. However, the biological consequences of deregulated MYB expression in the skin remain poorly understood.
View Article and Find Full Text PDFBackground: Alterations in the epidermal growth factor receptor and PI3K pathways in head and neck squamous cell carcinomas (HNSCCs) are frequent events that promote tumor progression. Ectopic expression of the epidermal growth factor receptor-targeting microRNA (miR), miR-27a* (miR-27a-5p), inhibits tumor growth. We sought to identify mechanisms mediating repression of miR-27a* in HNSCC, which have not been previously identified.
View Article and Find Full Text PDFOral squamous cell carcinoma (OSCC) is preceded by progressive oral premalignant lesions (OPL). Therefore, therapeutic strategies that prevent malignant progression of OPLs are expected to reduce the incidence of OSCC development. Immune checkpoint inhibitors that target the interaction of programmed death receptor 1 (PD-1) on T cells with the PD-1 ligand PD-L1 on cancer cells have been shown to extend the survival of patients with advanced OSCC.
View Article and Find Full Text PDFp53 (TP53) is the most frequently mutated gene in squamous cell carcinomas (SCCs) of the skin and head and neck. Certain p53 mutations are oncogenic and promote invasion and metastasis in SCCs. However, it is unclear how the oncogenic function of mutant p53 is modulated by other molecular alterations that co-exist in SCCs.
View Article and Find Full Text PDFA better understanding of the dynamics of molecular changes occurring during the early stages of oral tumorigenesis may help refine prevention and treatment strategies. We generated genome-wide expression profiles of microdissected normal mucosa, hyperplasia, dysplasia and tumors derived from the 4-NQO mouse model of oral tumorigenesis. Genes differentially expressed between tumor and normal mucosa defined the "tumor gene set" (TGS), including 4 non-overlapping gene subsets that characterize the dynamics of gene expression changes through different stages of disease progression.
View Article and Find Full Text PDFPurpose: Adenoid cystic carcinoma (ACC) is an indolent salivary gland malignancy, characterized by t(6;9) translocations and MYB-NFIB gene fusions in approximately 50% of the tumors. The genetic alterations underlying t(6;9)-negative and t(6;9)-positive/MYB-NFIB fusion-negative ACC remain unknown. To uncover the genetic alterations in ACC lacking the canonical translocation and fusion transcript and identify new abnormalities in translocation positive tumors.
View Article and Find Full Text PDFPurpose: Although the majority of patients with HPV(+) oropharyngeal cancers have a favorable prognosis, there are some patients with tumors that are resistant to aggressive chemoradiotherapy with unusual patterns of locoregional and systemic recurrences. Therefore, more effective therapies are needed. In this study, we investigated the chemosensitizing efficacy of the selective Wee-1 kinase inhibitor, AZD-1775, in HPV(+) head and neck squamous cell carcinoma (HNSCC).
View Article and Find Full Text PDFTP53 is the most frequently altered gene in head and neck squamous cell carcinoma, with mutations occurring in over two-thirds of cases, but the prognostic significance of these mutations remains elusive. In the current study, we evaluated a novel computational approach termed evolutionary action (EAp53) to stratify patients with tumors harboring TP53 mutations as high or low risk, and validated this system in both in vivo and in vitro models. Patients with high-risk TP53 mutations had the poorest survival outcomes and the shortest time to the development of distant metastases.
View Article and Find Full Text PDFAlthough cisplatin has played a role in "standard-of-care" multimodality therapy for patients with advanced squamous cell carcinoma of the head and neck (HNSCC), the rate of treatment failure remains particularly high for patients receiving cisplatin whose tumors have mutations in the TP53 gene. We found that cisplatin treatment of HNSCC cells with mutant TP53 leads to arrest of cells in the G2 phase of the cell cycle, leading us to hypothesize that the wee-1 kinase inhibitor MK-1775 would abrogate the cisplatin-induced G2 block and thereby sensitize isogenic HNSCC cells with mutant TP53 or lacking p53 expression to cisplatin. We tested this hypothesis using clonogenic survival assays, flow cytometry, and in vivo tumor growth delay experiments with an orthotopic nude mouse model of oral tongue cancer.
View Article and Find Full Text PDFPurpose: To investigate the molecular events associated with the activation of androgen receptor (AR) as a potential therapeutic target in patients with salivary duct carcinoma (SDC).
Experimental Design: Comprehensive molecular and expression analysis of the AR gene in 35 tumor specimens (20 males and 15 females) and cell lines derived from SDC using Western blotting and RT-PCR, FISH analysis, and DNA sequencing was conducted. In vitro and in vivo animal studies were also performed.
Purpose: Aggressive cutaneous squamous cell carcinoma (cSCC) is often a disfiguring and lethal disease. Very little is currently known about the mutations that drive aggressive cSCC.
Experimental Design: Whole-exome sequencing was performed on 39 cases of aggressive cSCC to identify driver genes and novel therapeutic targets.
Many mutant p53 proteins (mutp53s) exert oncogenic gain-of-function (GOF) properties, but the mechanisms mediating these functions remain poorly defined. We show here that GOF mutp53s inhibit AMP-activated protein kinase (AMPK) signaling in head and neck cancer cells. Conversely, downregulation of GOF mutp53s enhances AMPK activation under energy stress, decreasing the activity of the anabolic factors acetyl-CoA carboxylase and ribosomal protein S6 and inhibiting aerobic glycolytic potential and invasive cell growth.
View Article and Find Full Text PDFProteasome 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.
View Article and Find Full Text PDFThe molecular genetic alterations underlying the development and diversity of salivary gland carcinomas are largely unknown. To characterize these events, comparative genomic hybridization analysis was performed, using a single-nucleotide polymorphism microarray platform, of 60 fresh-frozen specimens that represent the main salivary carcinoma types: mucoepidermoid carcinoma (MEC), adenoid cystic carcinoma (ACC), and salivary duct carcinoma (SDC). The results were correlated with the clinicopathologic features and translocation statuses to characterize the genetic alterations.
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