Factors influencing hospital charges for tonsillectomy to treat obstructive sleep apnea in children.

PURPOSE: This study investigates the impact of patient characteristics and demographics on hospital charges for tonsillectomy as a treatment for pediatric obstructive sleep apnea (OSA). The aim is to identify potential disparities in hospital charges and contribute to efforts for equitable access to care. METHODS: Data from the 2016 Healthcare Cost and Utilization Project (HCUP) Kid Inpatient Database (KID) was analyzed. The sample included 3,304 pediatric patients undergoing tonsillectomy ± adenoidectomy for OSA. Variables such as age, race, length of stay, hospital region, residential location, payer information, and median household income were collected. The primary outcome variable was hospital charge. Statistical analyses, including t-tests, ANOVA, and multiple linear regression, were conducted. RESULTS: Among 3,304 pediatric patients undergoing tonsillectomy for OSA. The average total charges for tonsillectomy were $26,400, with a mean length of stay of 1.70 days. Significant differences in charges were observed based on patient race, hospital region, and payer information. No significant differences were found based on gender, discharge quarter, residential location, or median household income. Multiple linear regression showed race, hospital region, and residential location were significant predictors of total hospital charges. CONCLUSION: This study highlights the influence of patient demographics and regional factors on hospital charges for pediatric tonsillectomy in OSA cases. These findings underscore the importance of addressing potential disparities in healthcare access and resource allocation to ensure equitable care for children with OSA. Efforts should be made to promote fair and affordable treatment for all pediatric OSA patients, regardless of their demographic backgrounds.

Correction: Linking bacterial enterotoxins and alpha defensin 5 expansion in the Crohn's colitis: A new insight into the etiopathogenetic and differentiation triggers driving colonic inflammatory bowel disease.

[This corrects the article DOI: 10.1371/journal.pone.0246393.].

How effective are monthly departmental tracer surveys? A 5-year retrospective study of 138 surveys in 96 departments.

BACKGROUND: Repeat department-wide surveys are commonly employed for infection control. There remains debate concerning their cost-effectivess. The aim of the study was to measure the impact of repeat department-wide surveys in major in-patient departments (IPDs) and ambulatory facilities (AFs) in a tertiary care hospital. This was a retrospective study of 138 surveys condcuted in 96 departments over a 5-year period. METHODS: Two itemized questionnaires were designed to assess the most frequently inadequately adhered to infection control measures: one for IPD (with 21 items) and the other for AF (with 17 items). RESULTS: A total of 72 surveys were conducted in 49 IPDs, of which 39 (54%) were repeat surveys, and 66 surveys in 47 AFs, of which 33 (50%) were repeat surveys. The baseline rate of adherence/department was 71% ± 14 for the IPD, with an increase from the first to the last survey to 82% ± 13 (P = .037). In 15/21 measured infection control items, adherence improved. Adherence to infection control items was lower at baseline in the AFs than in the IPDs (63 ± 27), with an increase to 76 ± 20 (non significant). Although adherence improved for 9 items, it deteriorated in another 8, producing an overall statistically unchanged outcome. CONCLUSION: Repeat whole-department surveys contribute moderately to increased adherence to infection control guidelines. AFs demonstrate lower rates of adherence to infection control guidelines and are less receptive to educational measures.

Appointment Factors Contributing to Children with Speech Disorders Missing Speech and Language Pathology Appointments.

This study explores missed pediatric speech and language pathology (SLP) appointments to identify barriers for patients with speech disorders. Data from 839 referrals at Boston Medical Center, including demographics, appointment details, COVID-19 lockdown, and number of items on patient problem lists, were analyzed using chi-square tests and logistic regression. The findings revealed that lockdown status, appointment timing, appointment type (in-person vs telemedicine), referral department (ear, nose, and throat [ENT] vs non-ENT), sex, race, primary language, birthplace, and primary care provider presence had no significant impact on attendance. However, the number of patient-listed problems, prior cancelations, and missed appointments were significant predictors of patients who did not keep appointments. In conclusion, this research emphasizes the patient's problem list and past appointment behavior as critical factors in predicting missed SLP appointments for pediatric speech disorder patients. These insights can guide targeted interventions to improve attendance and enhance SLP engagement.

Harnessing the Synergy of Fe and Co with Carbon Nanofibers for Enhanced CO2 Hydrogenation Performance.

Amid growing concerns about climate change and energy sustainability, the need to create potent catalysts for the sequestration and conversion of CO2 to value-added chemicals is more critical than ever. This work describes the successful synthesis and profound potential of high-performance nanofiber catalysts, integrating earth-abundant iron (Fe) and cobalt (Co) as well as their alloy counterpart, FeCo, achieved through electrospinning and judicious thermal treatments. Systematic characterization using an array of advanced techniques, including SEM, TGA-DSC, ICP-MS, XRF, EDS, FTIR-ATR, XRD, and Raman spectroscopy, confirmed the integration and homogeneous distribution of Fe/Co elements in nanofibers and provided insights into their catalytic nuance. Impressively, the bimetallic FeCo nanofiber catalyst, thermally treated at 1050 °C, set a benchmark with an unparalleled CO2 conversion rate of 46.47% at atmospheric pressure and a consistent performance over a 55 h testing period at 500 °C. Additionally, this catalyst exhibited prowess in producing high-value hydrocarbons, comprising 8.01% of total products and a significant 31.37% of C2+ species. Our work offers a comprehensive and layered understanding of nanofiber catalysts, delving into their transformations, compositions, and structures under different calcination temperatures. The central themes of metal-carbon interactions, the potential advantages of bimetallic synergies, and the importance of structural defects all converge to define the catalytic performance of these nanofibers. These revelations not only deepen our understanding but also set the stage for future endeavors in designing advanced nanofiber catalysts with bespoke properties tailored for specific applications.

Superior antibody and membrane protein-specific T-cell responses to CoronaVac by intradermal versus intramuscular routes in adolescents.

BACKGROUND: Optimising the immunogenicity of COVID-19 vaccines to improve their protection against disease is necessary. Fractional dosing by intradermal (ID) administration has been shown to be equally immunogenic as intramuscular (IM) administration for several vaccines, but the immunogenicity of ID inactivated whole severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at the full dose is unknown. This study (NCT04800133) investigated the superiority of antibody and T-cell responses of full-dose CoronaVac by ID over IM administration in adolescents. METHODS: Participants aged 11-17 years received two doses of IM or ID vaccine, followed by the 3rd dose 13-42 days later. Humoral and cellular immunogenicity outcomes were measured post-dose 2 (IM-CC versus ID-CC) and post-dose 3 (IM-CCC versus ID-CCC). Doses 2 and 3 were administered to 173 and 104 adolescents, respectively. RESULTS: Spike protein (S) immunoglobulin G (IgG), S-receptor-binding domain (RBD) IgG, S IgG Fcγ receptor IIIa (FcγRIIIa)-binding, SNM [sum of individual (S), nucleocapsid protein (N), and membrane protein (M) peptide pool]-specific interleukin-2 (IL-2)+CD4+, SNM-specific IL-2+CD8+, S-specific IL-2+CD8+, N-specific IL-2+CD4+, N-specific IL-2+CD8+ and M-specific IL-2+CD4+ responses fulfilled the superior and non-inferior criteria for ID-CC compared to IM-CC, whereas IgG avidity was inferior. For ID-CCC, S-RBD IgG, surrogate virus neutralisation test, 90% plaque reduction neutralisation titre (PRNT90), PRNT50, S IgG avidity, S IgG FcγRIIIa-binding, M-specific IL-2+CD4+, interferon-γ+CD8+ and IL-2+CD8+ responses were superior and non-inferior to IM-CCC. The estimated vaccine efficacies were 49%, 52%, 66% and 79% for IM-CC, ID-CC, IM-CCC and ID-CCC, respectively. The ID groups reported more local, mild adverse reactions. CONCLUSION: This is the first study to demonstrate superior antibody and M-specific T-cell responses by ID inactivated SARS-CoV-2 vaccination and serves as the basis for future research to improve the immunogenicity of inactivated vaccines.

Exploring the appointment factors affecting pediatric patients with swallow disorders: Implications for speech and language pathology attendance.

INTRODUCTION: Feeding and swallowing disorders have become increasingly prevalent among children, necessitating effective management to prevent long-term complications. Speech and language pathology (SLP) services play a crucial role in diagnosing and treating these disorders. The objective of this study was to explore the factors that influence patient attendance to SLP appointments for swallow disorders. METHODS: This study was conducted at Boston Medical Center, involving 359 pediatric patients referred to SLP for swallow-related concerns. De-identified patient and appointment information was obtained from the electronic medical record. Various factors such as age, gender, race/ethnicity, primary language, appointment date/time, and COVID-19 lockdown status were analyzed to determine their impact on patient no-shows. Statistical analyses, including Chi-Square tests and binary logistic regression, were conducted using appropriate methodologies. RESULTS: 355 individual patient records were included in the analysis. Lockdown status and appointment time of day did not significantly affect patient no-shows. However, appointments conducted through telemedicine showed a significant difference in attendance. Patient referral department, gender, race, language, and being born at the medical center did not significantly influence patient attendance. Notably, having a primary care provider (PCP) at the medical center significantly affected patient attendance. Furthermore, previous appointment cancellations made a patient more likely to no-show. CONCLUSION: This study provides valuable insights into the factors influencing patient attendance at SLP appointments for pediatric swallowing disorders. Having a PCP at the medical center and utilizing telemedicine appointments were associated with higher attendance rates. Addressing appointment cancellations and investigating underlying reasons behind missed appointments should be prioritized in future research. Understanding these factors will facilitate the development of interventions to optimize patient attendance and improve the delivery of SLP services in pediatric populations.

Humoral and Cellular Immunogenicity of 3 Doses of BNT162b2 in Children With Kidney Diseases.

Introduction: Patients with severe kidney diseases are at risk of complications from COVID-19; however, little is known about the effectiveness of COVID-19 vaccines in children and adolescents with kidney diseases. Methods: We investigated the immunogenicity and safety of an accelerated 3-dose primary series of COVID-19 vaccination among 59 pediatric patients with chronic kidney disease (CKD) (mean age 12.9 years; 30 male) with or without immunosuppression, dialysis, or kidney transplant. Dosage was 0.1 ml BNT162b2 to those aged 5 to 11 years, and 0.3 ml BNT162b2 to those aged 11 to 18 years. Results: Three doses of either vaccine type elicited significant antibody responses that included spike receptor-binding domain (S-RBD) IgG (90.5%-93.8% seropositive) and surrogate virus neutralization (geometric mean sVNT% level, 78.6%-79.3%). There were notable T cell responses. Weaker neutralization responses were observed among those on immunosuppression, especially those receiving higher number of immunosuppressants or on mycophenolate mofetil. Neutralization was reduced against Omicron BA.1 compared to wild type (WT, i.e., ancestral) (post-dose 3 sVNT% level; 82.7% vs. 27.4%; P < 0.0001). However, the T cell response against Omicron BA.1 was preserved, which likely confers protection against severe COVID-19. Infected patients exhibited hybrid immunity after vaccination, as evidenced by the higher Omicron BA.1 neutralization response among these infected patients who received 2 doses compared with those who were uninfected. Generally mild or moderate adverse reactions following vaccines were reported. Conclusion: An accelerated 3-dose primary series with BNT162b2 is immunogenic and safe in young children and adolescents with kidney diseases.

How to be a GREAT mentor.

Formal training in how to mentor is not generally available to students, postdoctoral fellows, or junior faculty. We provide here a framework to develop as a mentor, using the GREAT model. This includes giving opportunities and opening doors; reaching out to help students identify their strengths and reach their goals; encouraging them by serving as a positive example; advising each mentee as an individual; and training them for independent thinking. In this personal view, we expand on each of these steps to illustrate how to develop a personalized mentoring style of your own. By combining these approaches, you as a mentor can work with your mentees to develop an effective and productive mentoring relationship.NEW & NOTEWORTHY We provide here a framework to develop as a mentor, using the GREAT model. This includes giving opportunities and opening doors; reaching out to help students identify their strengths and reach their goals; encouraging them by serving as a positive example; advising each mentee as an individual; and training them for independent thinking.

The effect of frenectomy for tongue-tie, lip-tie, or cheek-tie on breastfeeding outcomes: A systematic review of articles over time and suggestions for management.

OBJECTIVE: Tongue-tie, or ankyloglossia, is a common condition characterized by an abnormally short or tight lingual frenulum and is known to cause breastfeeding difficulties, leading to damage to the nipple, early discontinuation of breastfeeding, and delayed infant growth. In addition to tongue-tie, abnormal frenulums such as the labial frenulum and buccal frenulum can cause lip-tie and cheek-tie, respectively. While both of these conditions have been reported to potentially cause similar issues related to breastfeeding as tongue-tie, limited research has been conducted to understand their effects and how we should treat these conditions. METHODS: In this systematic review, we conducted a comprehensive search of MEDLINE to analyze the trend in publications of all three of these conditions and their impact on breastfeeding for the past 36 years. Keywords included, "tongue-tie", "lip-tie", "cheek-tie", and "breastfeeding outcomes". RESULTS: We found that publications describing the effect of only tongue-ties on breastfeeding have increased exponentially over time while less focus has been on other oral ties. It was also discovered that the majority of studies describing only lip-tie or tongue-tie were editorials, commentary, perspectives, or consensus statements. Finally, we found that articles describing more than one abnormal frenulum were more likely to be cited and articles describing tongue-tie only were published in the highest impact factor journals. CONCLUSION: This study revealed a significant increase in publications discussing tongue-tie and a lack of research on lip-tie and cheek-tie in relation to breastfeeding. The findings highlight the need for more comprehensive research and attention to lip-tie and cheek-tie, as well as standardized diagnostic criteria. Ongoing debate surrounding management of these conditions stem from the lack of investigations on the impact of these abnormal frenulums and outcomes post-frenectomy. Future high-quality studies, specifically prospective cohort studies and randomized controlled trials, are necessary to provide more robust evidence and guide clinical practice.

The use of a diversion tube to reduce blood culture contamination: A "real-life" quality improvement intervention study.

BACKGROUND: Blood culture contamination is associated with health care costs and potential patient harm. Diversion of the initial blood specimen reduces blood culture contamination. We report results of the "real-life" clinical implementation of this technique. METHODS: Following an educational campaign, use of a dedicated diversion tube was recommended prior to all blood cultures. Blood culture sets taken from adults using a diversion tube were defined as "diversion sets," those without, "non-diversion" sets. Blood culture contamination and true positive rates were compared for diversion and nondiversion sets and to nondiversion historical controls. A secondary analysis investigated efficacy of diversion by patient age. RESULTS: Out of 20,107 blood culture sets drawn, the diversion group included 12,774 (60.5%) and the nondiversion group 8,333 (39.5%) sets. The historical control group included 32,472 sets. Comparing nondiversion to diversion, contamination decreased by 31% (5.5% [461/8333] to 3.8% [489/12744], P < .0001]. Contamination was also 12% lower in diversion than historical controls [3.8% (489/12744) vs 4.3% (1,396/33,174) P = .02)]. The rate of true bacteremia was similar. In older patients, contamination rate was higher, and the relative reduction associated with diversion decreased (54.3% amongst 20-40-year-olds vs 14.5% amongst >80-year-olds). CONCLUSIONS: Use of a diversion tube in the ED reduced blood culture contamination in this large real life observational study. Efficacy decreased with increasing age, which requires further investigation.

Relationship between lumbar lordosis, pelvic parameters, PI-LL mismatch and outcome after short fusion surgery for lumbar degenerative disease. Literature review, rational and presentation of public study protocol: RELApSE study (registry for evaluation of lumbar artrodesis sagittal alignEment).

Background: Vertebral arthrodesis for degenerative pathology of the lumbar spine still remains burdened by clinical problems with significant negative results. The introduction of the sagittal balance assessment with the evaluation of the meaning of pelvic parameters and spinopelvic (PI-LL) mismatch offered new evaluation criteria for this widespread pathology, but there is a lack of consistent evidence on long-term outcome. Methods: The authors performed an extensive systematic review of literature, with the aim to identify all potentially relevant studies about the role and usefulness of the restoration or the assessment of Sagittal balance in lumbar degenerative disease. They present the study protocol RELApSE (NCT05448092 ID) and discuss the rationale through a comprehensive literature review. Results: From the 237 papers on this topic, a total of 176 articles were selected in this review. The analysis of these literature data shows sparse and variable evidence. There are no observations or guidelines about the value of lordosis restoration or PI-LL mismatch. Most of the works in the literature are retrospective, monocentric, based on small populations, and often address the topic evaluation partially. Conclusions: The RELApSE study is based on the possibility of comparing a heterogeneous population by pathology and different surgical technical options on some homogeneous clinical and anatomic-radiological measures aiming to understanding the value that global lumbar and segmental lordosis, distribution of lordosis, pelvic tilt, and PI-LL mismatch may have on clinical outcome in lumbar degenerative pathology and on the occurrence of adjacent segment disease.

Antibody and T cell responses against wild-type and Omicron SARS-CoV-2 after third-dose BNT162b2 in adolescents.

The high effectiveness of the third dose of BNT162b2 in healthy adolescents against Omicron BA.1 has been reported in some studies, but immune responses conferring this protection are not yet elucidated. In this analysis, our study (NCT04800133) aims to evaluate the humoral and cellular responses against wild-type and Omicron (BA.1, BA.2 and/or BA.5) SARS-CoV-2 before and after a third dose of BNT162b2 in healthy adolescents. At 5 months after 2 doses, S IgG, S IgG Fc receptor-binding, and neutralising antibody responses waned significantly, yet neutralising antibodies remained detectable in all tested adolescents and S IgG avidity increased from 1 month after 2 doses. The antibody responses and S-specific IFN-γ+ and IL-2+ CD8+ T cell responses were significantly boosted in healthy adolescents after a homologous third dose of BNT162b2. Compared to adults, humoral responses for the third dose were non-inferior or superior in adolescents. The S-specific IFN-γ+ and IL-2+ CD4+ and CD8+ T cell responses in adolescents and adults were comparable or non-inferior. Interestingly, after 3 doses, adolescents had preserved S IgG, S IgG avidity, S IgG FcγRIIIa-binding, against Omicron BA.2, as well as preserved cellular responses against BA.1 S and moderate neutralisation levels against BA.1, BA.2 and BA.5. Sera from 100 and 96% of adolescents tested at 1 and 5 months after two doses could also neutralise BA.1. Our study found high antibody and T cell responses, including potent cross-variant reactivity, after three doses of BNT162b2 vaccine in adolescents in its current formulation, suggesting that current vaccines can be protective against symptomatic Omicron disease.

Safety and immunogenicity of 3 doses of BNT162b2 and CoronaVac in children and adults with inborn errors of immunity.

Our study (NCT04800133) aimed to determine the safety and immunogenicity in patients with IEIs receiving a 3-dose primary series of mRNA vaccine BNT162b2 (age 12+) or inactivated whole-virion vaccine CoronaVac (age 3+) in Hong Kong, including Omicron BA.1 neutralization, in a nonrandomized manner. Intradermal vaccination was also studied. Thirty-nine patients were vaccinated, including 16 with homologous intramuscular 0.3ml BNT162b2 and 17 with homologous intramuscular 0.5ml CoronaVac. Two patients received 3 doses of intradermal 0.5ml CoronaVac, and 4 patients received 2 doses of intramuscular BNT162b2 and the third dose with intradermal BNT162b2. No safety concerns were identified. Inadequate S-RBD IgG and surrogate virus neutralization responses were found after 2 doses in patients with humoral immunodeficiencies and especially so against BA.1. Dose 3 of either vaccine increased S-RBD IgG response. T cell responses against SARS-CoV-2 antigens were detected in vaccinated IEI patients by intracellular cytokine staining on flow cytometry. Intradermal third dose vaccine led to high antibody response in 4 patients. The primary vaccination series of BNT162b2 and CoronaVac in adults and children with IEIs should include 3 doses for optimal immunogenicity.

Hypoxia-Inducible Expression of Annexin A6 Enhances the Resistance of Triple-Negative Breast Cancer Cells to EGFR and AR Antagonists.

Physiological changes such as hypoxia in the tumor microenvironment (TME) endow cancer cells with malignant properties, leading to tumor recurrence and rapid progression. Here, we assessed the effect of hypoxia (1% Oxygen) on the tumor suppressor Annexin A6 (AnxA6) and the response of triple-negative breast cancer (TNBC) cells to epidermal growth factor receptor (EGFR) and androgen receptor (AR) targeted therapies. We demonstrate that brief exposure of TNBC cells to hypoxia (within 24 h) is associated with down regulation of AnxA6 while > 24 h exposure cell type dependently stimulated the expression of AnxA6. Hypoxia depicted by the expression and stability of HIF-1/2α led to up regulation of the HIF target genes SLC2A1, PGK1 as well as AR and the AR target genes FABP-4 and PPAR-γ, but the cellular levels of AnxA6 protein decreased under prolonged hypoxia. Down regulation of AnxA6 in TNBC cells inhibited, while AnxA6 over expression enhanced the expression and cellular levels of HIF-1/2α, SLC2A1 and PGK1. RNAi mediated inhibition of hypoxia induced AnxA6 expression also strongly inhibited glucose uptake and ROS production in AnxA6 expressing TNBC cells. Using a luciferase reporter assay, we confirm that short-term exposure of cells to hypoxia inhibits while prolonged exposure of cells to hypoxia enhances AnxA6 promoter activity in HEK293T cells. Compared to cells cultured under normoxia, TNBC cells were more resistant to lapatinib under hypoxic conditions, and the downregulation of AnxA6 sensitized the cells to EGFR as well as AR antagonists. These data suggest that AnxA6 is a hypoxia inducible gene and that targeting AnxA6 upregulation may be beneficial in overcoming TNBC resistance to EGFR and/or AR targeted therapies.

Rate and Risk Factors for Carbapenem Resistant Acinetobacter baumannii Clinical Infections in Colonized Patients.

BACKGROUND: Carbapenem-resistant Acinetobacter baumannii (CRAB) is an important cause of nosocomial infections. Active surveillance for CRAB carriage to identify and isolate colonized patients is used to reduce transmission. OBJECTIVES: To assess the rate and risks of clinical infection among CRAB-carrier and non-carrier patients. METHODS: Hospitalized patients from whom CRAB screening-cultures were obtained between January and June 2018 were identified retrospectively. All CRAB-carriers were compared to a convenient sample of non-carriers and were followed to detect development of CRAB clinical infection during admission. RESULTS: We compared 115 CRAB carriers to 166 non-carriers. The median age in the study group was 76 years (IQR 71-87) vs. 65 years (55-79) in the non-carriers group (P < 0.001). Residence in a nursing facility, debilitated state, and admission to medical wards vs. intensive care units were more frequent among CRAB-carriers (P < 0.001). Mechanically ventilated patients included 51 CRAB carriers (44%) and 102 non-carriers (61%). Clinical infection developed in 49 patients (17%), primarily CRAB pneumonia. Of the CRAB-carriers and non-carriers, 26/115 (23%) and 23/166 (14%), respectively, developed a clinical infection (P = 0.05). One-third of the ventilated patients were infected. Debilitated state and antibiotic treatment during hospitalization were linked to higher infection rates (P = 0.01). Adjusted analysis showed that mechanical ventilation and CRAB colonization were strongly associated with clinical infection (P < 0.05). CONCLUSIONS: The rate of CRAB infection among carriers was high. Mechanical ventilation and CRAB colonization were associated with CRAB clinical infection, primarily pneumonia.

Fetuin-A Promotes 3-Dimensional Growth in LNCaP Prostate Cancer Cells by Sequestering Extracellular Vesicles to Their Surfaces to Act as Signaling Platforms.

The present studies were conducted to evaluate key serum proteins and other components that mediate anchorage-independent growth (3-D growth) of LNCaP prostate cancer cells as spheroids. The cells were cultured on ultra-low attachment plates in the absence and presence of fetuin-A and with or without extracellular vesicles. The data show that fetuin-A (alpha 2HS glycoprotein) is the serum protein that mediates 3-D growth in these cells. It does so by sequestering extracellular vesicles of various sizes on the surfaces of rounded cells that grow as spheroids. These vesicles in turn transmit growth signals such as the activation of AKT and MAP kinases in a pattern that differs from the activation of these key growth signaling pathways in adherent and spread cells growing in 2-D. In the process of orchestrating the movement and disposition of extracellular vesicles on these cells, fetuin-A is readily internalized in adhered and spread cells but remains on the surfaces of non-adherent cells. Taken together, our studies suggest the presence of distinct signaling domains or scaffolding platforms on the surfaces of prostate tumor cells growing in 3-D compared to 2-D.

Identification of MAGEC2/CT10 as a High Calcium-Inducible Gene in Triple-Negative Breast Cancer.

The expression of the melanoma/cancer-testis antigen MAGEC2/CT10 is restricted to germline cells, but like most cancer-testis antigens, it is frequently upregulated in advanced breast tumors and other malignant tumors. However, the physiological cues that trigger the expression of this gene during malignancy remain unknown. Given that malignant breast cancer is often associated with skeletal metastasis and co-morbidities such as cancer-induced hypercalcemia, we evaluated the effect of high Ca2+ on the calcium-sensing receptor (CaSR) and potential mechanisms underlying the survival of triple-negative breast cancer (TNBC) cells at high Ca2+. We show that chronic exposure of TNBC cells to high Ca2+ decreased the sensitivity of CaSR to Ca2+ but stimulated tumor cell growth and migration. Furthermore, high extracellular Ca2+ also stimulated the expression of early response genes such as FOS/FOSB and a unique set of genes associated with malignant tumors, including MAGEC2. We further show that the MAGEC2 proximal promoter is Ca2+ inducible and that FOS/FOSB binds to this promoter in a Ca2+- dependent manner. Finally, downregulation of MAGEC2 strongly inhibited the growth of TNBC cells in vitro. These data suggest for the first time that MAGEC2 is a high Ca2+ inducible gene and that aberrant expression of MAGEC2 in malignant TNBC tissues is at least in part mediated by an increase in circulating Ca2+via the AP-1 transcription factor.

Reduced Expression of Annexin A6 Induces Metabolic Reprogramming That Favors Rapid Fatty Acid Oxidation in Triple-Negative Breast Cancer Cells.

The ability of cancer cells to alter their metabolism is one of the major mechanisms underlying rapid tumor progression and/or therapeutic resistance in solid tumors, including the hard-to-treat triple-negative breast cancer (TNBC) subtype. Here, we assessed the contribution of the tumor suppressor, Annexin A6 (AnxA6), in the metabolic adaptation of basal-like (AnxA6-low) versus mesenchymal-like (AnxA6-high), as well as in lapatinib-resistant TNBC cells. Using model basal-like and mesenchymal-like TNBC cell lines, we show that TNBC cells also exhibit metabolic heterogeneity. The downregulation of AnxA6 in TNBC cells generally attenuated mitochondrial respiration, glycolytic flux, and cellular ATP production capacity resulting in a quiescent metabolic phenotype. We also show that AnxA6 depletion in mesenchymal-like TNBC cells was associated with a rapid uptake and mitochondrial fatty acid oxidation and diminished lipid droplet accumulation and altered the lipogenic metabolic phenotype of these cells to a lypolytic metabolic phenotype. The overexpression or chronic lapatinib-induced upregulation of AnxA6 in AnxA6-low TNBC cells reversed the quiescent/lypolytic phenotype to a more lipogenic/glycolytic phenotype with gluconeogenic precursors as additional metabolites. Collectively, these data suggest that the expression status of AnxA6 in TNBC cells underlies distinct metabolic adaptations of basal-like and mesenchymal-like TNBC subsets in response to cellular stress and/or therapeutic intervention and suggest AnxA6 as a biomarker for metabolic subtyping of TNBC subsets.