229 research outputs found
Effect of Lipid Headgroup Charge and pH on the Stability and Membrane Insertion Potential of Calcium Condensed Gene Complexes
This document is the Accepted Manuscript version of a Published Work that appeared in final form in Langmuir, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://doi.org/10.1021/la504970n.Noncovalently condensed complexes of genetic material, cell penetrating peptides (CPPs), and calcium chloride present a nonviral route to improve transfection efficiency of nucleic acids (e.g., pDNA and siRNA). However, the exact mechanisms of membrane insertion and delivery of macromolecule complexes to intracellular locations as well as their stability in the intracellular environment are not understood. We show that calcium condensed gene complexes containing different hydrophilic (i.e., dTAT, K9, R9, and RH9) and amphiphilic (i.e., RA9, RL9, and RW9) CPPs formed stable cationic complexes of hydrodynamic radii 100 nm at neutral pH. However, increasing the acidity caused the complexes to become neutral or anionic and increase in size. Using zwitterionic and anionic phospholipid monolayers as models that mimic the membrane composition of the outer leaflet of cell membranes and intracellular vesicles and pHs that mimic the intracellular environment, we study the membrane insertion potential of these seven gene complexes (CPP/pDNA/Ca2+ complexes) into model membranes. At neutral pH, all gene complexes demonstrated the highest insertion potential into anionic phospholipid membranes, with complexes containing amphiphilic peptides showing the maximum insertion. However, at acidic pH, the gene complexes demonstrated maximum monolayer insertion into zwitterionic lipids, irrespective of the chemical composition of the CPP in the complexes. Our results suggest
Salvage surgery for squamous cell carcinoma of the head and neck in the era of immunotherapy: Is it time to clarify our guidelines?
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146561/1/cncr31717_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146561/2/cncr31717.pd
The hidden link of exosomes to head and neck cancer
Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Head and neck squamous cell carcinoma (HNSCC) represents an aggressive and heteroge-nous group of cancers whose pathologies remain largely unresolved. Despite recent advances in HNSCC therapeutic strategies, the overall survival of HNSCC patients remains poor and continues to prompt efforts to develop more effective therapies. Exosomes are a subtype of extracellular vesicles secreted by a variety of cells that have begun to spark significant interest in their roles in cancer. As membranous vesicles, spanning from 30–150 nm in diameter, exosomes mediate the transport of various molecules, such as proteins, nucleic acids, and lipids, intercellularly throughout the body. In doing so, exosomes not only act to deliver materials to cancer cells but also as signals that can confer their progression. Accumulating evidence shows the direct correlation between exosomes and the aggressiveness of HNSCC. However, more research is warranted in this field to further our under-standing. In this review, we attempt to highlight the tumor-supporting roles and therapeutic potential of exosomes in HNSCC. We introduce first the biogenesis and component features of exosomes, followed by their involvement in HNSCC proliferation and metastasis. We then move on to discuss HNSCC-derived exosomes’ influence on the tumor microenvironment and their function in tumor drug resistance. Finally, we explore the promising potential of exosomes as HNSCC biomarkers and therapeutic targets and drug carriers for HNSCC treatments.Peer reviewe
Antitumor Activity of 2,9-Di-\u3cem\u3eSec\u3c/em\u3e-Butyl-1,10-Phenanthroline
The anti-tumor effect of a chelating phen-based ligand 2,9-di-sec-butyl-1,10-phenanthroline (dsBPT) and its combination with cisplatin were examined in both lung and head and neck cancer cell lines and xenograft animal models in this study. The effects of this agent on cell cycle and apoptosis were investigated. Protein markers relevant to these mechanisms were also assessed. We found that the inhibitory effect of dsBPT on lung and head and neck cancer cell growth (IC50 ranged between 0.1–0.2 μM) was 10 times greater than that on normal epithelial cells. dsBPT alone induced autophagy, G1 cell cycle arrest, and apoptosis. Our in vivo studies indicated that dsBPT inhibited tumor growth in a dose-dependent manner in a head and neck cancer xenograft mouse model. The combination of dsBPT with cisplatin synergistically inhibited cancer cell growth with a combination index of 0.3. Moreover, the combination significantly reduced tumor volume as compared with the untreated control (p = 0.0017) in a head and neck cancer xenograft model. No organ related toxicities were observed in treated animals. Our data suggest that dsBPT is a novel and potent antitumor drug that warrants further preclinical and clinical development either as a single agent or in combination with known chemotherapy drugs such as cisplatin
A systematic review and recommendations on the use of plasma EBV DNA for nasopharyngeal carcinoma
Introduction: Nasopharyngeal carcinoma (NPC) is an endemic malignancy in Southeast Asia, particularly Southern China. The classical non-keratinising cell type is almost unanimously associated with latent Epstein-Barr virus (EBV) infection. Circulating plasma EBV DNA can be a useful biomarker in various clinical aspects, but comprehensive recommendations and international guidelines are still lacking. We conducted a systematic review of all original articles on the clinical application of plasma EBV DNA for NPC; we further evaluated its strengths and limitations for consideration as standard recommendations. Methods: The search terms 'nasopharyngeal OR nasopharynx', and 'plasma EBV DNA OR cell-free EBV OR cfEBV' were used to identify full-length articles published up to December 2020 in the English literature. Three authors independently reviewed the article titles, removed duplicates and reviewed the remaining articles for eligibility. Results: A total of 81 articles met the eligibility criteria. Based on the levels of evidence and grades of recommendation assessed, it is worth considering the inclusion of plasma EBV DNA in screening, pre-treatment work-up for enhancing prognostication and tailoring of treatment strategy, monitoring during radical treatment, post-treatment surveillance for early detection of relapse, and monitoring during salvage treatment for recurrent or metastatic NPC. One major limitation is the methodology of measurement requiring harmonisation for consistent comparability. Conclusions: The current comprehensive review supports the inclusion of plasma EBV DNA in international guidelines in the clinical aspects listed, but methodological issues must be resolved before global application. 2021 Elsevier Ltd. All rights reserved
Chromosome translocations, gene fusions, and their molecular consequences in pleomorphic salivary gland adenomas
Salivary gland tumors are a heterogeneous group of tumors originating from the major and minor salivary glands. The pleomorphic adenoma (PA), which is the most common subtype, is a benign lesion showing a remarkable morphologic diversity and that, upon recurrence or malignant transformation, can cause significant clinical problems. Cytogenetic studies of >500 PAs have revealed a complex and recurrent pattern of chromosome rearrangements. In this review, we discuss the specificity and frequency of these rearrangements and their molecular/clinical consequences. The genomic hallmark of PA is translocations with breakpoints in 8q12 and 12q13-15 resulting in gene fusions involving the transcription factor genes PLAG1 and HMGA2. Until recently, the association between these two oncogenic drivers was obscure. Studies of the Silver-Russel syndrome, a growth retardation condition infrequently caused by mutations in IGF2/HMGA2/PLAG1, have provided new clues to the understanding of the molecular pathogenesis of PA. These studies have demonstrated that HMGA2 is an upstream regulator of PLAG1 and that HMGA2 regulates the expression of IGF2 via PLAG1. This provides a novel explanation for the 8q12/12q13-15 aberrations in PA and identifies IGF2 as a major oncogenic driver and therapeutic target in PA. These studies have important diagnostic and therapeutic implications for patients with PA.info:eu-repo/semantics/publishedVersio
Oncologic Outcomes After Clinically Node-Negative Salvage Laryngectomy
IMPORTANCE: Controversy exists regarding management of the clinically node-negative neck in patients with recurrent larynx or hypopharynx cancers who received total laryngectomy after definitive radiation with or without chemotherapy.
OBJECTIVE: To explore clinical and oncologic outcomes after elective neck dissection vs observation in patients who received clinically node-negative salvage total laryngectomy.
DESIGN, SETTING, AND PARTICIPANTS: This cohort study was performed from January 2009 to June 2021 at a single, high-volume tertiary care center. Follow-up was conducted through June 2021 for all patients. Survival outcomes were based on at least 2 years of follow-up. Patients aged 18 years or older with recurrent, clinically node-negative larynx or hypopharynx tumors after definitive nonsurgical treatment who were treated with a salvage total laryngectomy were included. Data were analyzed from October 2021 through September 2022.
EXPOSURES: Elective neck dissection.
MAIN OUTCOMES AND MEASURES: Presence and location of occult nodal metastasis in electively dissected necks, along with differences in fistula rates and overall and disease-free survival between patients receiving elective neck dissection vs observation.
RESULTS: Among 107 patients receiving clinically node-negative salvage total laryngectomy (median [IQR] age, 65.0 [57.8-71.3] years; 91 [85.0%] men), 81 patients underwent elective neck dissection (75.7%) and 26 patients underwent observation (24.3%). Among patients with elective neck dissection, 13 patients had occult nodal positivity (16.0%). Recurrent supraglottic (4 of 20 patients [20.0%]) or advanced T classification (ie, T3-T4; 12 of 61 patients [19.7%]) had an occult nodal positivity rate of 20% or more, and positive nodes were most likely to occur in levels II and III (II: 6 of 67 patients [9.0%]; III: 6 of 65 patients [9.2%]; VI: 3 of 44 patients [6.8%]; IV: 3 of 62 patients [4.8%]; V: 0 of 4 patients; I: 0 of 18 patients). There was a large difference in fistula rate between elective neck dissection (12 patients [14.8%]) and observed (8 patients [30.8%]) groups (difference, 16.0 percentage points; 95% CI, -3.4 to 35.3 percentage points), while the difference in fistula rate was negligible between 50 patients undergoing regional or free flap reconstruction (10 patients [20.0%]) vs 57 patients undergoing primary closure (10 patients [17.5%]) (difference, 2.5 percentage points; 95% CI, -12.4 to 17.3 percentage points). Undergoing elective neck dissection was not associated with a clinically meaningful improvement in overall or disease-free survival compared with observation. Recurrent hypopharynx subsite was associated with an increased risk of death (hazard ratio, 4.28; 95% CI, 1.81 to 10.09) and distant recurrence (hazard ratio, 7.94; 95% CI, 2.07 to 30.48) compared with glottic subsite.
CONCLUSIONS AND RELEVANCE: In this cohort study, patients with recurrent supraglottic or advanced T classification tumors had an increased occult nodal positivity rate, elective neck dissection was not associated with survival, and patients with recurrent hypopharynx subsite were more likely to have a distant recurrence and die of their disease. These findings suggest that underlying disease pathology rather than surgical management may be associated with survival outcomes in this population
Targeting Angiogenesis in Squamous Cell Carcinoma of the Head and Neck : Opportunities in the Immunotherapy Era
Simple Summary Therapies for squamous cell carcinomas of the head and neck (SCCHN) have been rapidly evolving, initially with the inclusion of immunotherapy, but more recently with the consideration of anti-angiogenic therapies. Recent preclinical and clinical data reveal a strong correlation between vascular endothelial growth factor (VEGF) and the progression of SCCHN, with nearly 90% of these malignancies expressing VEGF. Our review article not only elaborates on the utility of anti-VEGF therapies on SCCHN but also its interaction with the immune environment. Furthermore, we detailed the current data on immunotherapies targeting SCCHN and how this could be coupled with anti-angiogenics therapies. Despite the lack of approved anti-angiogenic therapies in squamous cell carcinoma of the head and neck (SCCHN), preclinical and more recent clinical evidence support the role of targeting the vascular endothelial growth factor (VEGF) in this disease. Targeting VEGF has gained even greater interest following the recent evidence supporting the role of immunotherapy in the management of advanced SCCHN. Preclinical evidence strongly suggests that VEGF plays a role in promoting the growth and progression of SCCHN, and clinical evidence exists as to the value of combining this strategy with immunotherapeutic agents. Close to 90% of SCCHNs express VEGF, which has been correlated with a worse clinical prognosis and an increased resistance to chemotherapeutic agents. As immunotherapy is currently at the forefront of the management of advanced SCCHN, revisiting the rationale for targeting angiogenesis in this disease has become an even more attractive proposition.Peer reviewe
Targeting Angiogenesis in Squamous Cell Carcinoma of the Head and Neck : Opportunities in the Immunotherapy Era
Simple Summary Therapies for squamous cell carcinomas of the head and neck (SCCHN) have been rapidly evolving, initially with the inclusion of immunotherapy, but more recently with the consideration of anti-angiogenic therapies. Recent preclinical and clinical data reveal a strong correlation between vascular endothelial growth factor (VEGF) and the progression of SCCHN, with nearly 90% of these malignancies expressing VEGF. Our review article not only elaborates on the utility of anti-VEGF therapies on SCCHN but also its interaction with the immune environment. Furthermore, we detailed the current data on immunotherapies targeting SCCHN and how this could be coupled with anti-angiogenics therapies. Despite the lack of approved anti-angiogenic therapies in squamous cell carcinoma of the head and neck (SCCHN), preclinical and more recent clinical evidence support the role of targeting the vascular endothelial growth factor (VEGF) in this disease. Targeting VEGF has gained even greater interest following the recent evidence supporting the role of immunotherapy in the management of advanced SCCHN. Preclinical evidence strongly suggests that VEGF plays a role in promoting the growth and progression of SCCHN, and clinical evidence exists as to the value of combining this strategy with immunotherapeutic agents. Close to 90% of SCCHNs express VEGF, which has been correlated with a worse clinical prognosis and an increased resistance to chemotherapeutic agents. As immunotherapy is currently at the forefront of the management of advanced SCCHN, revisiting the rationale for targeting angiogenesis in this disease has become an even more attractive proposition.Peer reviewe
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