DCLK1-Mediated Regulation of Invadopodia Dynamics and Matrix Metalloproteinase Trafficking Drives Invasive Progression in Head and Neck Squamous Cell Carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is a major health concern due to its high mortality from poor treatment responses and locoregional tumor invasion into life sustaining structures in the head and neck. A deeper comprehension of HNSCC invasion mechanisms holds the potential to inform targeted therapies that may enhance patient survival. We previously reported that doublecortin like kinase 1 (DCLK1) regulates invasion of HNSCC cells. Here, we tested the hypothesis that DCLK1 regulates proteins within invadopodia to facilitate HNSCC invasion. Invadopodia are specialized subcellular protrusions secreting matrix metalloproteinases that degrade the extracellular matrix (ECM). Through a comprehensive proteome analysis comparing DCLK1 control and shDCLK1 conditions, our findings reveal that DCLK1 plays a pivotal role in regulating proteins that orchestrate cytoskeletal and ECM remodeling, contributing to cell invasion. Further, we demonstrate in TCGA datasets that DCLK1 levels correlate with increasing histological grade and lymph node metastasis. We identified higher expression of DCLK1 in the leading edge of HNSCC tissue. Knockdown of DCLK1 in HNSCC reduced the number of invadopodia, cell adhesion and colony formation. Using super resolution microscopy, we demonstrate localization of DCLK1 in invadopodia and colocalization with mature invadopodia markers TKS4, TKS5, cortactin and MT1-MMP. We carried out phosphoproteomics and validated using immunofluorescence and proximity ligation assays, the interaction between DCLK1 and motor protein KIF16B. Pharmacological inhibition or knockdown of DCLK1 reduced interaction with KIF16B, secretion of MMPs, and cell invasion. This research unveils a novel function of DCLK1 within invadopodia to regulate the trafficking of matrix degrading cargo. The work highlights the impact of targeting DCLK1 to inhibit locoregional invasion, a life-threatening attribute of HNSCC.

The Contribution of the Human Oral Microbiome to Oral Disease: A Review.

The oral microbiome is an emerging field that has been a topic of discussion since the development of next generation sequencing and the implementation of the human microbiome project. This article reviews the current literature surrounding the oral microbiome, briefly highlighting most recent methods of microbiome characterization including cutting edge omics, databases for the microbiome, and areas with current gaps in knowledge. This article also describes reports on microorganisms contained in the oral microbiome which include viruses, archaea, fungi, and bacteria, and provides an in-depth analysis of their significant roles in tissue homeostasis. Finally, we detail key bacteria involved in oral disease, including oral cancer, and the current research surrounding their role in stimulation of inflammatory cytokines, the role of gingival crevicular fluid in periodontal disease, the creation of a network of interactions between microorganisms, the influence of the planktonic microbiome and cospecies biofilms, and the implications of antibiotic resistance. This paper provides a comprehensive literature analysis while also identifying gaps in knowledge to enable future studies to be conducted.

Nocardia niwae Disseminated Nocardiosis: A Novel Species Presenting Concurrently With Lung Adenocarcinoma.

Nocardia includes over 90 species of filamentous gram-positive bacilli that may cause disease in immunocompromised or immunocompetent hosts. Presentations may include pulmonary, 4, cutaneous, or disseminated infections. Tissue diagnosis may be required as it may mimic alternative etiologies. There is a paucity of data regarding rarer species of Nocardia. Intraspecies variability in antimicrobial susceptibility limits many treatment regimens to in-vitro activity data and treatment regimens often must be tailored to individual patients based on microbiologic cultures. We describe the case of a 63-year-old female who presented with disseminated Nocardia niwae, a species that was previously first identified in Florida for which little clinical data is known, along with concurrent lung adenocarcinoma with pulmonary and central nervous system lesions. Typical susceptibility patterns are discussed along with potential side effects of antimicrobial therapy.

Disseminated Toxoplasmosis in an Allogeneic Hematopoietic Stem Cell Transplant Recipient: A Case Report and Review of the Current Literature.

Reactivation infections in hematopoietic stem cell transplants are mitigated by prophylactic regimens. Despite high rates of exposure, morbidity and mortality secondary to toxoplasmosis are limited to subsets of patients such as immunocompromised persons. We describe the first case of disseminated toxoplasmosis in a double umbilical cord blood transplant recipient.

Immunogenicity of the COVID-19 Two-Vaccination Series Among Hematologic Malignancies: Report of Three Cases of Breakthrough Infection.

Data is limited on the immunogenicity of the COVID-19 two-vaccination series among patients with hematologic malignancies and current guidelines do not recommend routine monitoring for post-vaccine antibodies. However, we describe three patients who developed severe or critical COVID-19 infections six months after vaccination. This highlights the importance of routine testing of COVID-19 IgG Spike, semi-quantitative antibodies post-vaccination, particularly among immunocompromised patients.

Clinical characteristics and predictors of survival in adults with coronavirus disease 2019 receiving tocilizumab.

Coronavirus disease 2019 (COVID-19) can progress to cytokine storm that is associated with organ dysfunction and death. The purpose of the present study is to determine clinical characteristics associated with 28 day in-hospital survival in patients with coronavirus disease 2019 (COVID-19) that received tocilizumab. This was a retrospective observational cohort study conducted at a five hospital health system in Michigan, United States. Adult patients with confirmed COVID-19 that were admitted to the hospital and received tocilizumab for cytokine storm from March 1, 2020 through April 3, 2020 were included. Patients were grouped into survivors and non-survivors based on 28 day in-hospital mortality. Study day 0 was defined as the day tocilizumab was administered. Factors independently associated with in-hospital survival at 28 days after tocilizumab administration were assessed. Epidemiologic, demographic, laboratory, prognostic scores, treatment, and outcome data were collected and analyzed. Clinical response was collected and defined as a decline of two levels on a six-point ordinal scale of clinical status or discharged alive from the hospital. Of the 81 patients included, the median age was 64 (58-71) years and 56 (69.1%) were male. The 28 day in-hospital mortality was 43.2%. There were 46 (56.8%) patients in the survivors and 35 (43.2%) in the non-survivors group. On study day 0 no differences were noted in demographics, clinical characteristics, severity of illness scores, or treatments received between survivors and non-survivors. C-reactive protein was significantly higher in the non-survivors compared to survivors. Compared to non-survivors, recipients of tocilizumab within 12 days of symptom onset was independently associated with survival (adjusted OR: 0.296, 95% CI: 0.098-0.889). SOFA score ≥8 on day 0 was independently associated with mortality (adjusted OR: 2.842, 95% CI: 1.042-7.753). Clinical response occurred more commonly in survivors than non-survivors (80.4% vs. 5.7%; p < 0.001). Improvements in the six-point ordinal scale and SOFA score were observed in survivors after tocilizumab. Early receipt of tocilizumab in patients with severe COVID-19 was an independent predictor for in-hospital survival at 28 days.