Mental health-related service and medicine use among a cohort of urban Aboriginal children and young people: Data linkage study.

OBJECTIVE: The objective was to describe mental health service and psychotropic medicine use among a cohort of Aboriginal young people and quantify their relation to sociodemographic, family and health factors. METHODS: In a prospective cohort study with data linkage, 892 Aboriginal children aged 0-17 years living in urban and regional areas of New South Wales, Australia, were included. We assessed mental health-related service use, paediatric service use and psychotropic medicine dispensing claims covered by the Australian Government Medicare Benefits Schedule and the Pharmaceutical Benefits Scheme from July 2012 to June 2017. RESULTS: Most children (71%) did not have a record of mental health service or psychotropic medication use. 18.7% had ⩾1 mental health-related service claim; 26.7% had ⩾1 paediatric service claim; and 20.3% had ⩾1 psychotropic medicine dispensing claim. General practitioner services were the most accessed mental health-related service (17.4%) and 12.7% had been dispensed attention-deficit hyperactivity disorder medicines. Child characteristics associated with treatment included emotional and behavioural problems (prevalence ratio: 1.97, 95% confidence interval = [1.46, 2.64] for mental health services; prevalence ratio: 2.87, 95% confidence interval = [2.07, 3.96] for medicines) and risky behaviour (prevalence ratio: 1.56, 95% confidence interval = [1.12, 2.16] for mental health services; prevalence ratio: 2.28, 95% confidence interval = [1.54, 3.37] for medicines). Parent-related factors included chronic illness (prevalence ratio: 1.42, 95% confidence interval = [1.03, 1.95] for mental health services; prevalence ratio: 2.00, 95% confidence interval = [1.49, 2.69] for medicines) and functional limitations (prevalence ratio: 1.61, 95% confidence interval = [1.16, 2.24] for mental health services; prevalence ratio: 1.86, 95% confidence interval = [1.34, 2.59] for medicines). CONCLUSIONS: Most Aboriginal children and young people did not have claims for mental health services or medicines. Aboriginal children with emotional and behavioural problems, or parents with health problems were more likely to have mental health service or medicine claims.

Socioeconomic disadvantage and engagement with digital contact tracing for COVID-19 in Western Sydney: A secondary analysis of surveillance data.

OBJECTIVE: COVID-19 outcomes were highly inequitably distributed in Australia and worldwide. The digitalisation of public health interventions offers resource-efficiency and increased capacity for pandemic responses, but risks excluding the elderly and disadvantaged, reinforcing existing inequalities. Despite this, there has been little evaluation of the determinants of uptake of digital contact tracing. This paper describes the use of digital contact tracing for COVID-19 in a population in metropolitan Sydney and the determinants of engagement in this population. METHODS: Routinely collected surveillance data for residents of Western Sydney Local Health District, returning a positive SARS-CoV-2 result between 1st August 2021 and 12th February 2022, were extracted including responses to a digital contact tracing questionnaire. Individual records were linked to area-level socioeconomic indices of disadvantage. Descriptive analyses explored characteristics of non-responders and geospatial variation. Logistic regression was undertaken to evaluate the effect of age, sex and socioeconomic disadvantage on the odds of response. RESULTS: Of the 133 055 individuals included, 130 645 (98%) were issued a digital contact tracing questionnaire, and 106 432 (81%) responded. Odds of responding were lower in males (odds ratio: 0.79), individuals aged 80+ (odds ratio: 0.17) and the most disadvantaged communities (odds ratio: 0.32). CONCLUSIONS: Digital data collection for contact tracing was a scalable and efficient tool in the context of the Western Sydney Local Health District COVID-19 response. However, older people and individuals in disadvantaged communities were less likely to engage. IMPLICATIONS FOR PUBLIC HEALTH: Responses to future pandemics should leverage the resource-efficiency of digital interventions but should avoid compounding existing health inequalities.

Polymorphonuclear myeloid-derived suppressor cells and phosphatidylinositol-3 kinase gamma are critical to tobacco-mimicking oral carcinogenesis in mice.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is a devastating disease most often associated with tobacco consumption that induces a field of mutations from which a tumor arises. Identification of ways to prevent the emergence of cancer in high-risk patients is an ultimate goal for combatting all types of cancer, including OSCC. METHODS: Our study employs a mouse model of tongue carcinogenesis induced by tobacco carcinogen mimetic, 4-nitroquinoline 1-oxide (4NQO), to establish tongue dysplasia and OSCC. We use conventional histology, immunohistochemistry, multispectral imaging, mass cytometry, novel cell lines, pharmaceutical inhibition of PI3Kγ, T-cell suppression assays and mouse transplant models in our functional experimentation. RESULTS: In our study, we identify Ly6G+ granulocytes as the most abundant immune cell type in a model of tongue carcinogenesis induced by tobacco carcinogen mimetic 4NQO. Targeting Ly6G+ granulocytes with a pharmacologic inhibitor of PI3Kγ, an isoform of PI3K exclusively expressed by myeloid cells, resulted in reduced tongue dysplasia severity, and reduced rates of OSCC. Importantly, we performed functional assays with the Ly6G+ granulocytes induced in cell line models of 4NQO carcinogenesis to demonstrate that these granulocytes have increased polymorphonuclear myeloid-derived suppressor cells (PMN-MDSC) activity against T-cell proliferation and these PMN-MDSCs play a functional role in promoting tumor formation by inhibiting tumor regression in a PI3Kγ-dependent manner. CONCLUSIONS: Overall, our data suggest that recruitment of PMN-MDSCs to sites of dysplasia is critical to immune suppression of CD8 T cells, thereby permitting malignancy, and PI3Kγ inhibitors are one mechanism to reduce PMN-MDSC recruitment, immunosuppression and tumorigenesis in OSCC.

Inducible nitric oxide synthase (iNOS)-activated Cxcr2 signaling in myeloid cells promotes TGFß-dependent squamous cell carcinoma lung metastasis.

Transforming growth factor beta (TGFß) activity is linked to metastasis in many cancer types, but whether TGFß activity is necessary for squamous cell carcinoma (SCC) lung metastasis has not been studied. Here we used a lung metastatic SCC model derived from keratin 15 (K15). KrasG12D.Smad4-/- SCC and human SCC specimens to identify metastasis drivers and test therapeutic interventions. We demonstrated that a TGFß receptor (TGFßR) inhibitor reduced lung metastasis in mouse SCC correlating with reduced CD11b+/Ly6G+ myeloid cells positive for inducible nitric oxide synthase (iNOS). Further, TGFß activity and iNOS were higher in primary human oral SCCs with metastasis than SCCs without metastasis. Consistently, either depleting myeloid cells with anti-Gr1 antibody or inhibiting iNOS with L-N6-(1-iminoethyl)-l-lysine (L-NIL) reduced SCC lung metastasis. L-NIL treated tumor-bearing mice exhibited reductions in tumor-infiltrating myeloid cells and in plasma Cxcl5 levels, and attenuated primary tumor growth with increased apoptosis and decreased proliferation. Blocking Cxcl5 with an antagonist of its receptor Cxcr2, SB225002, also reduced SCC lung metastasis.

IL-22RA2 Is a SMAD7 Target Mediating the Alleviation of Dermatitis and Psoriatic Phenotypes in Mice.

Long-term management of inflammatory skin diseases is challenging because of side effects from repeated use of systemic treatments or topical corticosteroids. This study sought to identify the mechanisms and developmental therapeutics for these diseases using genetic models and pharmacological approaches. We found that mice overexpressing SMAD7 in keratinocytes but not mice overexpressing the N-terminal domain of SMAD7 (i.e., N-SMAD7) were resistant to imiquimod-induced T helper 1/17- and T helper 2-type inflammation. We generated a Tat-PYC-SMAD7 (truncated SMAD7 protein encompassing C-terminal SMAD7 and PY motif fused with cell-penetrating Tat peptide). Topically applied Tat-PYC-SMAD7 to inflamed skin entered cells upon contact and attenuated imiquimod-, 2,4-dinitrofluorobenzene-, and tape-stripping-induced inflammation. RNA-sequencing analyses of mouse skin exposed to these insults showed that in addition to inhibiting TGFß/NF-κB, SMAD7 blunted IL-22/signal transducer and activator of transcription 3 activation and associated pathogenesis, which is due to SMAD7 transcriptionally upregulating IL-22 antagonist IL-22RA2. Mechanistically, SMAD7 facilitated nuclear translocation and DNA binding of C/EBPß to IL22RA2 promoter for IL22RA2 transactivation. Consistent with the observations in mice mentioned earlier, transcript levels of IL22RA2 were increased in human atopic dermatitis and psoriasis lesions with clinical remission. Our study identified the anti-inflammation functional domain of SMAD7 and suggests the mechanism and feasibility for developing SMAD7-based biologics as a topical therapy for skin inflammatory disorders.

Aboriginal Young People's Experiences of Accessibility in Mental Health Services in Two Regions of New South Wales, Australia.

This article assesses the accessibility of mainstream mental health services (MMHSs) in two regions of New South Wales (NSW), Australia, based on experiences and perspectives of Aboriginal young people aged 16-25. Semi-structured yarning interviews were conducted with thirteen Aboriginal young people in two regions of NSW. Thematic analysis was undertaken by all research team members to identify major themes from the data and conceptual connections between them. The identified themes from individual analysis and coding were triangulated during several analysis meetings to finalise the key themes and findings. Aboriginal young people had no experience of engaging with early-intervention MMHSs. MMHSs were identified as inaccessible, with most participants unaware that MMHSs existed in each region. Due to MMHSs being inaccessible, many Aboriginal young people presented to emergency departments (EDs) during a crisis. Aboriginal Community Controlled Health Services (ACCHSs) were identified as key providers of accessible, culturally meaningful, and effective social and emotional wellbeing (SEWB) service support for Aboriginal young people in NSW. If health and wellbeing outcomes are to improve for Aboriginal young people in NSW, MMHSs must increase accessibility for Aboriginal young people requiring SEWB support.

Revisiting laminin and extracellular matrix remodeling in metastatic squamous cell carcinoma: What have we learned after more than four decades of research?

Patients with squamous cell carcinoma (SCC) have significantly lower survival upon the development of distant metastases. The extracellular matrix (ECM) is a consistent yet dynamic influence on the metastatic capacity of SCCs. The ECM encompasses a milieu of structural proteins, signaling molecules, and enzymes. Just over 40 years ago, the fibrous ECM glycoprotein laminin was identified. Roughly four decades of research have revealed a pivotal role of laminins in metastasis. However, trends in ECM alterations in some cancers have been applied broadly to all metastatic diseases, despite evidence that these characteristics vary by tumor type. We will summarize how laminins influence the SCC metastatic process exclusively. Enhanced laminin protein deposition occurs at the invasive edge of SCC tumors, which correlates with elevated levels of laminin-binding ß1 integrins on SCC cells, increased MMP-3 presence, worse prognosis, and lymphatic dissemination. Although these findings are significant, gaps in knowledge of the formation of a premetastatic niche, the processes of intra- and extravasation, and the contributions of the ECM to SCC metastatic cell dormancy persist. Bridging these gaps requires novel in vitro systems and animal models that reproduce tumor-stromal interactions and spontaneous metastasis seen in the clinic. These advances will allow accurate assessment of laminins to predict responders to transforming growth factor-ß inhibitors and immunotherapy, as well as potential combinatorial therapies with the standard of care. Such clinical interventions may drastically improve quality of life and patient survival by explicitly targeting SCC metastasis.

Epidermal growth factor receptor signaling in precancerous keratinocytes promotes neighboring head and neck cancer squamous cell carcinoma cancer stem cell-like properties and phosphoinositide 3-kinase inhibitor insensitivity.

Head and neck squamous cell carcinoma (HNSCC) is commonly associated with tobacco and alcohol consumption that induce a "precancerous field," with phosphoinositide 3-kinase (PI3K) signaling being a common driver. However, the preclinical effectiveness of PI3K inhibitors has not necessarily translated to remarkable benefit in HNSCC patients. Thus, we sought to determine how precancerous keratinocytes influence HNSCC proliferation, cancer stem cell (CSC) maintenance, and response to PI3K inhibitors. We used the NOK keratinocyte cell line as a model of preneoplastic keratinocytes because it harbors two frequent genetic events in HNSCC, CDKN2A promoter methylation and TP53 mutation, but does not form tumors. NOK cell coculture or NOK cell-conditioned media promoted HNSCC proliferation, PI3K inhibitor resistance, and CSC phenotypes. SOMAscan-targeted proteomics determined the relative levels of >1300 analytes in the media conditioned by NOK cells and HNSCC cells ± PI3K inhibitor. These results demonstrated that NOK cells release abundant levels of ligands that activate epidermal growth factor receptor (EGFR) and fibroblast growth factor receptor (FGFR), two receptor tyrosine kinases with oncogenic activity. Inhibition of EGFR, but not FGFR, blunted PI3K inhibitor resistance and CSC phenotypes induced by NOK cells. Our results demonstrate that precancerous keratinocytes can directly support neighboring HNSCC by activating EGFR. Importantly, PI3K inhibitor sensitivity was not necessarily a cancer cell-intrinsic property, and the tumor microenvironment impacts therapeutic response and supports CSCs. Additionally, combined inhibition of EGFR with PI3K inhibitor diminished EGFR activation induced by PI3K inhibitor and potently inhibited cancer cell proliferation and CSC maintenance.

Therapeutic Intervention Using a Smad7-Based Tat Protein to Treat Radiation-Induced Oral Mucositis.

PURPOSE: Recent studies reported therapeutic effects of Smad7 on oral mucositis in mice without compromising radiation therapy-induced cancer cell killing in neighboring oral cancer. This study aims to assess whether a Smad7-based biologic can treat oral mucositis in a clinically relevant setting by establishing an oral mucositis model in dogs and analyzing molecular targets. METHODS AND MATERIALS: We created a truncated human Smad7 protein fused with the cell-penetrating Tat tag (Tat-PYC-Smad7). We used intensity modulated radiation therapy to induce oral mucositis in dogs and applied Tat-PYC-Smad7 to the oral mucosa in dose-finding studies after intensity modulated radiation therapy. Clinical outcomes were evaluated. Molecular targets were analyzed in biopsies and serum samples. RESULTS: Tat-PYC-Smad7 treatment significantly shortened the duration of grade 3 oral mucositis based on double-blinded Veterinary Radiation Therapy Oncology Group scores and histopathology evaluations. Topically applied Tat-PYC-Smad7 primarily penetrated epithelial cells and was undetectable in serum. NanoString nCounter Canine IO Panel identified that, compared to the vehicle samples, top molecular changes in Tat-PYC-Smad7 treated samples include reductions in inflammation and cell death and increases in cell growth and DNA repair. Consistently, immunostaining shows that Tat-PYC-Smad7 reduced DNA damage and neutrophil infiltration with attenuated TGF-ß and NFκB signaling. Furthermore, IL-1ß and TNF-α were lower in Tat-PYC-Smad7 treated mucosa and serum samples compared to those in vehicle controls. CONCLUSIONS: Topical Tat-PYC-Smad7 application demonstrated therapeutic effects on oral mucositis induced by intensity modulated radiation therapy in dogs. The local effects of Tat-PYC-Smad7 targeted molecules involved in oral mucositis pathogenesis as well as reduced systemic inflammatory cytokines.

Cancer-Associated Fibroblasts Facilitate Squamous Cell Carcinoma Lung Metastasis in Mice by Providing TGFß-Mediated Cancer Stem Cell Niche.

Cancer-associated fibroblasts (CAFs) have been shown to enhance squamous cell carcinoma (SCC) growth, but it is unclear whether they promote SCC lung metastasis. We generated CAFs from K15.KrasG12D.Smad4-/- mouse SCCs. RNA expression analyses demonstrated that CAFs had enriched transforming growth factor-beta (TGFß) signaling compared to normal tissue-associated fibroblasts (NAFs), therefore we assessed how TGFß-enriched CAFs impact SCC metastasis. We co-injected SCC cells with CAFs to the skin, tail vein, or the lung to mimic sequential steps of lung metastasis. CAFs increased SCC volume only in lung co-transplantations, characterized with increased proliferation and angiogenesis and decreased apoptosis compared to NAF co-transplanted SCCs. These CAF effects were attenuated by a clinically relevant TGFß receptor inhibitor, suggesting that CAFs facilitated TGFß-dependent SCC cell seeding and survival in the lung. CAFs also increased tumor volume when co-transplanted to the lung with limiting numbers of SCC cancer stem cells (CSCs). In vitro, CSC sphere formation and invasion were increased either with co-cultured CAFs or with CAF conditioned media (which contains the highest TGFß1 concentration) and these CAF effects were blocked by TGFß inhibition. Further, TGFß activation was higher in primary human oral SCCs with lung metastasis than SCCs without lung metastasis. Similarly, TGFß activation was detected in the lungs of mice with micrometastasis. Our data suggest that TGFß-enriched CAFs play a causal role in CSC seeding and expansion in the lung during SCC metastasis, providing a prognostic marker and therapeutic target for SCC lung metastasis.

Distinct immune microenvironment profiles of therapeutic responders emerge in combined TGFß/PD-L1 blockade-treated squamous cell carcinoma.

Transforming growth factor beta (TGFß) and programmed death-ligand 1 (PD-L1) are often overproduced in refractory squamous cell carcinoma (SCC). We examined spatial patterns of PD-L1+ cells in mouse and human SCCs and found that PD-L1 was primarily expressed on infiltrating leukocytes. Although combined TGFß and PD-L1 blockade are undergoing cancer clinical trials, there are no predictive markers for therapeutic responders. To address this, we used both a small molecule TGFß inhibitor in combination with anti-PD-L1 and a bifunctional fusion protein targeting both TGFß and PD-L1 to treat mouse SCCs and found TGFß inhibition enhanced PD-L1 blockade-induced tumor eradication in multiple tumor models. Furthermore, we identified distinct cell populations of responders and non-responders to bintrafusp alfa, with responders showing a shift toward a more immune-permissive microenvironment. The cellular and molecular signatures of responders versus non-responders to combined TGFß and PD-L1 blockade provide important insights into future personalized immunotherapy in SCC.

Outcomes reported in evaluations of programs designed to improve health in Indigenous people.

OBJECTIVE: To assess the outcomes reported and measured in evaluations of complex health interventions in Indigenous communities. DATA SOURCES: We searched all publications indexed in MEDLINE, PreMEDLINE, EMBASE, PsycINFO, EconLit, and CINAHL until January 2020 and reference lists from included papers were hand-searched for additional articles. STUDY DESIGN: Systematic review. DATA COLLECTION/EXTRACTION METHODS: We included all primary studies, published in peer-reviewed journals, where the main objective was to evaluate a complex health intervention developed specifically for an Indigenous community residing in a high-income country. Only studies published in English were included. Quantitative and qualitative data were extracted and summarized. PRINCIPAL FINDINGS: Of the 3523 publications retrieved, 62 evaluation studies were included from Australia, the United States, Canada, and New Zealand. Most studies involved less than 100 participants and were mainly adults. We identified outcomes across 13 domains: clinical, behavioral, process-related, economic, quality of life, knowledge/awareness, social, empowerment, access, environmental, attitude, trust, and community. Evaluations using quantitative methods primarily measured outcomes from the clinical and behavioral domains, while the outcomes reported in the qualitative studies were mostly from the process-related and empowerment domains. CONCLUSION: The outcomes from qualitative evaluations, which better reflect the impact of the intervention on participant health, remain different from the outcomes routinely measured in quantitative evaluations. Measuring the outcomes from qualitative evaluations alongside outcomes from quantitative evaluations could result in more relevant evaluations to inform decision making in Indigenous health.

Transforming Growth Factor-ß Signaling in Fibrotic Diseases and Cancer-Associated Fibroblasts.

Transforming growth factor-ß (TGF-ß) signaling is essential in embryo development and maintaining normal homeostasis. Extensive evidence shows that TGF-ß activation acts on several cell types, including epithelial cells, fibroblasts, and immune cells, to form a pro-fibrotic environment, ultimately leading to fibrotic diseases. TGF-ß is stored in the matrix in a latent form; once activated, it promotes a fibroblast to myofibroblast transition and regulates extracellular matrix (ECM) formation and remodeling in fibrosis. TGF-ß signaling can also promote cancer progression through its effects on the tumor microenvironment. In cancer, TGF-ß contributes to the generation of cancer-associated fibroblasts (CAFs) that have different molecular and cellular properties from activated or fibrotic fibroblasts. CAFs promote tumor progression and chronic tumor fibrosis via TGF-ß signaling. Fibrosis and CAF-mediated cancer progression share several common traits and are closely related. In this review, we consider how TGF-ß promotes fibrosis and CAF-mediated cancer progression. We also discuss recent evidence suggesting TGF-ß inhibition as a defense against fibrotic disorders or CAF-mediated cancer progression to highlight the potential implications of TGF-ß-targeted therapies for fibrosis and cancer.

Case Report: Spontaneous Rupture of Inferior Epigastric Artery Masquerading as Inguinal Hernia.

INTRODUCTION: Spontaneous rupture of an inferior epigastric artery aneurysm is rare with very few cases reported in the medical literature. Although surgical options are available, this case was managed conservatively with outpatient management. CASE REPORT: A 29-year-old male presented with right groin pain and swelling that was initially felt to be consistent with an incarcerated inguinal hernia. Further evaluation revealed spontaneous rupture of an inferior epigastric artery aneurysm. The patient was treated conservatively and was ultimately discharged home from the emergency department. CONCLUSION: Due to the similar clinical presentations, it was important to consider a broad differential to ultimately arrive at the correct diagnosis. In some reported cases of spontaneous epigastric artery aneurysm, surgical intervention was required for control of the bleeding. In our patient, however, conservative management was employed, and the patient was able to be safely discharged with close outpatient follow-up.

Development of syngeneic murine cell lines for use in immunocompetent orthotopic lung cancer models.

BACKGROUND: Immunocompetent animal models are required to study tumor-host interactions, immunotherapy, and immunotherapeutic combinations, however the currently available immunocompetent lung cancer models have substantial limitations. While orthotopic models potentially help fill this gap, the utility of these models has been limited by the very small number of murine lung cancer cell lines capable of forming orthotopic tumors in immunocompetent C57BL/6 hosts. METHODS: Primary lung tumors with specific genetic alterations were created in C57BL/6 background mice. These tumors were then passaged through other animals to increase tumorigenicity and select for the ability to grow in a non-self animal. Once tumors demonstrated growth in a non-self host, cell lines were established. Successful cell lines were evaluated for the ability to produce orthotopic lung tumors in immunocompetent hosts. RESULTS: We produced six murine lung cancer lines capable of orthotopic lung tumor formation in immunocompetent C57BL/6 animals. These lines demonstrate the expected genetic alterations based on their primary tumor genetics. CONCLUSIONS: These novel cell lines will be useful for evaluating tumor-host interactions, the impact of specific oncogenic alterations on the tumor microenvironment, and immunotherapeutic approaches. This method of generating murine lines capable of orthotopic growth can likely be applied to other tumors and will broaden the applicability of pre-clinical testing of immunotherapeutic treatment regimens.

Deletion of p53 and Hyper-Activation of PIK3CA in Keratin-15+ Stem Cells Lead to the Development of Spontaneous Squamous Cell Carcinoma.

Squamous cell carcinoma (SCC) is the second commonest type of skin cancer, and SCCs make up about 90% of head and neck cancers (HNSCCs). HNSCCs harbor two frequent molecular alterations, namely, gain-of-function alterations of phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) and loss-of-function mutations of tumor protein p53 (TP53). However, it remains poorly understood whether HNSCCs harboring different genetic alterations exhibit differential immune tumor microenvironments (TME). It also remains unknown whether PIK3CA hyperactivation and TP53 deletion can lead to SCC development spontaneously. Here, we analyzed the Cancer Genome Atlas (TCGA) datasets of HNSCCs and found that patients with both PIK3CA and TP53 alterations exhibited worse survival, significantly lower CD8 tumor infiltrating lymphocytes (TILs) and higher M0 macrophages than other controls. To better model human tumorigenesis, we deleted TP53 and constitutively activated PIK3CA in mouse keratin-15-expressing stem cells, which leads to the spontaneous development of multilineage tumors including SCCs, termed Keratin-15-p53-PIK3CA (KPPA) tumors. KPPA tumors were heavily infiltrated with myeloid-derived suppressor cells (MDSCs), with a drastically increased ratio of polymorphonuclear-MDSC (PMN-MDSC) versus monocytic-MDSC (M-MDSC). CD8 TILs expressed more PD-1 and reduced their polyfunctionality. Overall, we established a genetic model to mimic human HNSCC pathogenesis, manifested with an immunosuppressive TME, which may help further elucidate immune evasion mechanisms and develop more effective immunotherapies for HNSCCs.

Cancer Cell CD44 Mediates Macrophage/Monocyte-Driven Regulation of Head and Neck Cancer Stem Cells.

Tumor-associated macrophages (TAM) in the tumor microenvironment (TME) cooperate with cancer stem cells (CSC) to maintain stemness. We recently identified cluster of differentiation 44 (CD44) as a surface marker defining head and neck squamous cell carcinoma (HNSCC) CSC. PI3K-4EBP1-SOX2 activation and signaling regulate CSC properties, yet the upstream molecular control of this pathway and the mechanisms underlying cross-talk between TAM and CSC in HNSCC remain largely unknown. Because CD44 is a molecular mediator in the TME, we propose here that TAM-influenced CD44 signaling could mediate stemness via the PI3K-4EBP1-SOX2 pathway, possibly by modulating availability of hyaluronic acid (HA), the main CD44 ligand. HNSCC IHC was used to identify TAM/CSC relationships, and in vitro coculture spheroid models and in vivo mouse models were used to identify the influence of TAMs on CSC function via CD44. Patient HNSCC-derived TAMs were positively and negatively associated with CSC marker expression at noninvasive and invasive edge regions, respectively. TAMs increased availability of HA and increased cancer cell invasion. HA binding to CD44 increased PI3K-4EBP1-SOX2 signaling and the CSC fraction, whereas CD44-VCAM-1 binding promoted invasive signaling by ezrin/PI3K. In vivo, targeting CD44 decreased PI3K-4EBP1-SOX2 signaling, tumor growth, and CSC. TAM depletion in syngeneic and humanized mouse models also diminished growth and CSC numbers. Finally, a CD44 isoform switch regulated epithelial-to-mesenchymal plasticity as standard form of CD44 and CD44v8-10 determined invasive and tumorigenic phenotypes, respectively. We have established a mechanistic link between TAMs and CSCs in HNSCC that is mediated by CD44 intracellular signaling in response to extracellular signals. SIGNIFICANCE: These findings establish a mechanistic link between tumor cell CD44, TAM, and CSC properties at the tumor-stroma interface that can serve as a vital area of focus for target and drug discovery.

Parents' and carers' views on factors contributing to the health and wellbeing of urban Aboriginal children.

OBJECTIVE: To identify and describe caregiver perspectives on factors important for the health and wellbeing of urban Aboriginal children. METHODS: Caregivers of Aboriginal children participating in the Study of Environment on Aboriginal Resilience and Child Health (SEARCH) were asked to describe the single most important factor that would help their children to be healthy and well. Responses were analysed using thematic and content analysis. RESULTS: Of the 626 carers in SEARCH, 425 (68%) provided a response. We identified 13 factors related to: loving family relationships, culturally competent healthcare, food security, active living, community services, education, social and emotional connectedness, safety, breaking cycles of disadvantage, housing availability and affordability, positive Aboriginal role models, strong culture, and carer wellbeing. CONCLUSIONS: Aligning with holistic concepts of health, caregivers believe that a broad range of child, family and environmental-level factors are needed to ensure the health and wellbeing of Aboriginal children. Implications for public health: This study highlights the importance of providing public health initiatives that enable equal access to the social determinants of health for carers of Aboriginal children. Affordable and adequate housing, food security, culturally appropriate healthcare, and family and community connectedness remain critical areas for targeted initiatives.

PARP Inhibition Enhances Radiotherapy of SMAD4-Deficient Human Head and Neck Squamous Cell Carcinomas in Experimental Models.

PURPOSE: SMAD4 loss causes genomic instability and the initiation/progression of head and neck squamous cell carcinoma (HNSCC). Here, we study whether SMAD4 loss sensitizes HNSCCs to olaparib (PARP inhibitor) in combination with radiotherapy (RT). EXPERIMENTAL DESIGN: We analyzed HNSCC The Cancer Genome Atlas data for SMAD4 expression in association with FANC/BRCA family gene expression. Human HNSCC cell lines were screened for sensitivity to olaparib. Isogenic HNSCC cell lines were generated to restore or reduce SMAD4 expression and treated with olaparib, radiation, or the combination. HNSCC pretreatment specimens from a phase I trial investigating olaparib were analyzed. RESULTS: SMAD4 levels correlated with levels of FANC/BRCA genes in HNSCC. HNSCC cell lines with SMAD4 homozygous deletion were sensitive to olaparib. In vivo, olaparib or RT monotherapy reduced tumor volumes in SMAD4-mutant but not SMAD4-positive tumors. Olaparib with RT dual therapy sustained tumor volume reduction in SMAD4-deficient (mutant or knockdown) xenografts, which exhibited increased DNA damage and cell death compared with vehicle-treated tumors. In vitro, olaparib alone or in combination with radiation caused lower clonogenic survival, more DNA damage-associated cell death, and less proliferation in SMAD4-deficient cells than in SMAD4-positive (endogenous SMAD4 or transduced SMAD4) cells. Applicable to clinic, 5 out of 6 SMAD4-negative HNSCCs and 4 out of 8 SMAD4-positive HNSCCs responded to a standard treatment plus olaparib in a phase I clinical trial, and SMAD4 protein levels inversely correlated with DNA damage. CONCLUSIONS: SMAD4 levels are causal in determining sensitivity to PARP inhibition in combination with RT in HNSCCs.

Protection of swine by potent neutralizing anti-Japanese encephalitis virus monoclonal antibodies derived from vaccination.

Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus endemic in the Asia Pacific region. Despite use of several highly effective vaccines, it is estimated that up to 44,000 new cases of Japanese encephalitis (JE) occur every year including 14,000 deaths and 24,000 survivors with permanent sequelae. Humoral immunity induced by vaccination is critical for effective protection. Potently neutralizing antibodies reactive with the JEV envelope (E) protein are important since protective immune responses induced by both live-attenuated and inactivated JE vaccines target the E protein. Our understanding of how vaccine-induced humoral immunity protects vaccinees from morbidity and mortality is, however, limited and largely obtained from in vitro studies. With the exception of neurovirulence mouse models, very few platforms are available for evaluating the protective efficacy of neutralizing antibodies against JEV in vivo. Swine are a major amplifying host in the natural JEV transmission cycle and develop multiple pathological outcomes similar to humans infected with JEV. In this study, prophylactic passive immunization was performed in a miniature swine model, using two vaccination-induced monoclonal antibodies (mAb), JEV-31 and JEV-169. These were selected as representatives for antibodies reactive with the major antigenic structures in the E protein of JEV and related flaviviruses. JEV-31 recognizes the lateral ridge of E protein domain III (EDIII) whilst JEV-169 has a broad footprint of binding involving residues throughout domains I (EDI) and II (EDII) of the E protein. Detection of neutralizing antibodies in the serum of immunized animals mimics the presence of neutralizing antibodies in vaccinated individuals. Passive immunization with both mAbs significantly reduced the severity of diseases that resemble the symptoms of human JE including fever, viremia, viral shedding, systemic infection, and neuroinvasion. In contrast to the uniformed decrease of viral loads in lymphoid and central nervous systems, distinct kinetics in the onset of fever and viremia between animals receiving JEV-31 and JEV-169 suggest potential differences in immune protection mechanisms between anti-EDI and anti-EDIII neutralizing antibodies elicited by vaccination. Our data demonstrate the feasibility of using swine models in characterizing the protective humoral immunity against JEV and increase our understanding of how clonal populations of anti-E mAbs derived from JE vaccination protect against infection in vivo.