Clinical significance and different strategies for re-elevation of plasma EBV-DNA during treatment in pediatric EBV-associated hemophagocytic lymphohistiocytosis.

OBJECTIVE: Monitoring the disease status of Epstein-Barr virus (EBV)-related hemophagocytic lymphohistiocytosis (HLH) patients is crucial. This study aimed to investigate the different strategies and outcomes of patients with EBV-HLH and re-elevated EBV-DNA. METHOD: A retrospective analysis was conducted on 20 patients diagnosed with EBV-HLH. Clinical features, laboratory tests, treatments, plasma EBV-DNA levels, and outcomes were assessed. Three cases were highlighted for detailed analysis. RESULTS: Nine of the 20 patients had a re-elevation of EBV-DNA during treatment, and 55.5 % (5/9) experienced relapses. Patients with persistently positive plasma EBV-DNA (n = 4) and those with re-elevated EBV-DNA after conversion (n = 9) showed a significantly higher relapse rate compared to those with persistently negative EBV-HLH (n = 7) (p < 0.05). Among the highlighted cases, Case 1 exhibited plasma EBV-DNA re-elevation after four weeks of treatment without relapse, maintaining stability with the original treatment regimen, and eventually, his plasma EBV-DNA turned negative. In Case 2, plasma EBV-DNA was elevated again with a recurrence of HLH after L-DEP. Consequently, she underwent allogeneic hematopoietic stem cell transplantation and eventually achieved complete remission (CR) with negative plasma EBV-DNA. Case 3 experienced plasma EBV-DNA re-elevation after L-DEP but remained in CR, discontinuing chemotherapy without relapse. CONCLUSION: The re-elevation of plasma EBV-DNA during EBV-HLH treatment poses challenges in determining disease status and treatment strategies. Optimal management decisions require a combination of the level of elevated EBV-DNA, the intensity of hyperinflammation, and the patient's immune function.

circ_SIRT1 upregulates ATG12 to facilitate Imatinib resistance in CML through interacting with EIF4A3.

Imatinib is the current gold standard for patients with chronic myeloid leukemia (CML). However, the primary and acquired drug resistance seriously limits the efficacy. To identify novel therapeutic target in Imatinib-resistant CML is of crucial clinical significance. CircRNAs have been demonstrated the essential regulatory roles in the progression and drug resistance of cancers. In this study, we identified a novel circRNA (circ_SIRT1), derived from the SIRT1, which is up-regulated in CML. The high expression of circ_SIRT1 is correlated with drug resistance in CML. Knockdown of circ_SIRT1 regulated K562/R cells viability, invasion and apoptosis. Besides, the inhibition of circ_SIRT1 attenuated autophagy level and reduced IC50 to Imatinib of K562/R cells. Mechanistically, circ_SIRT1 directly binds to the transcription factor Eukaryotic Translation Initiation Factor 4A3(EIF4A3) and regulated EIF4A3-mediated transcription of Autophagy Related 12 (ATG12), thereby affecting Imatinib resistance and autophagy level. Overexpression of ATG12 reversed the regulative effects induced by knockdown of circ_SIRT1. Taken together, our findings revealed circ_SIRT1 acted as a potential tumor regulator in CML and unveiled the underlying mechanism on regulating Imatinib resistance. circ_SIRT1 may serve as a novel therapeutic target and provide crucial clinical implications for Imatinib-resistant CML treatment.

Clinical characteristics and risk factors of acute lymphoblastic leukemia in children with severe infection during maintenance treatment.

BACKGROUND: Infection is the most common adverse event of acute lymphoblastic leukemia (ALL) treatment and is also one of the main causes of death. METHODS: To investigate the clinical characteristics and risk factors of severe infections during the maintenance phase of ALL treatment, we conducted a retrospective study. RESULTS: A total of 181 children were eligible and 46 patients (25.4%) suffered from 51 events of severe infection, most of which occurred in the first half year of the maintenance phase (52.9%). The most common infection was pulmonary infection (86.3%) followed by bloodstream infection (19.6%). The main symptoms of ALL patients with pulmonary infection were fever, cough, and shortness of breath. The main manifestations of computer tomography (CT) were ground glass shadow (56.8%), consolidation shadow (27.3%), and streak shadow (25%). Multivariate binary logistic regression analysis showed that agranulocytosis, agranulocytosis ≥7 days, anemia, and low globulin level were independent risk factors for severe infection during the maintenance phase (all p < 0.05). CONCLUSIONS: Taken together, blood routine examinations and protein levels should be monitored regularly for ALL patients in the maintenance phase, especially in the first 6 months. For ALL patients with risk factors, preventive anti-infective or supportive therapies can be given as appropriate to reduce the occurrence of severe infections.

Analysis 33 patients of non-DS-AMKL with or without acquired trisomy 21 from multiple centers and compared to 118 AML patients.

BACKGROUND: Acute megakaryoblastic leukemia (AMKL) without Down syndrome (non-DS-AMKL) usually a worse outcome than DS-AMKL. Acquired trisomy 21(+21) was one of the most common cytogenetic abnormalities in non-DS-AMKL. Knowledge of the difference in the clinical characteristics and prognosis between non-DS-AMKL with +21 and those without +21 is limited. OBJECTIVE: Verify the clinical characteristics and prognosis of non-DS-AMKL with +21. METHOD: We retrospectively analyzed 33 non-DS-AMKL pediatric patients and 118 other types of AML, along with their clinical manifestations, laboratory data, and treatment response. RESULTS: Compared with AMKL without +21, AMKL with +21 has a lower platelet count (44.04 ± 5.01G/L) at onset (P > 0.05). Differences in remission rates between AMKL and other types of AML were not significant. Acquired trisomy 8 in AMKL was negatively correlated with the long-term OS rate (P < 0.05), while +21 may not be an impact factor. Compared with the other types of AML, AMKL has a younger onset age (P < 0.05), with a mean of 22.27 months. Anemia, hemorrhage, lymph node enlargement, lower white blood cell, and complex karyotype were more common in AMKL (P < 0.05). AMKL has a longer time interval between onset to diagnosis (53.61 ± 71.15 days) (P < 0.05), and patients with a diagnosis delay ≥3 months always presented as thrombocytopenia or pancytopenia initially. CONCLUSIONS: Due to high heterogeneity, high misdiagnosis rate, and myelofibrosis, parts of AMKL may take a long time to be diagnosed, requiring repeated bone marrow punctures. Complex karyotype was common in AMKL. +21 may not be a promising indicator of a poor prognosis.

Hypothyroidism in induction chemotherapy of children with acute lymphoblastic leukaemia: A single-centre study.

Hypothyroidism as a long-term complication in cancer survivors has been an issue, but few studies have focused on changes in thyroid hormone levels during chemotherapy for leukaemia. This retrospective study was conducted to assess the characteristics of children with acute lymphoblastic leukaemia (ALL) and hypothyroidism during induction chemotherapy and to investigate the prognostic value of hypothyroidism in ALL. Patients with a detailed thyroid hormone profile at ALL diagnosis were enrolled. Hypothyroidism was defined as low serum levels of free tetraiodothyronine (FT4) and/or free triiodothyronine (FT3). The Kaplan-Meier method was used to create survival curves, and multivariate Cox regression analysis was used to screen prognostic factors associated with progression-free survival (PFS) and overall survival (OS). There were 276 children eligible for the study, and 184 patients (66.67%) were diagnosed with hypothyroidism, including 90 cases (48.91%) with functional central hypothyroidism and 82 cases (44.57%) with low T3 syndrome. Hypothyroidism was correlated with the dosages of L-Asparaginase (L-Asp) (P = .004) and glucocorticoids (P = .010), central nervous system (CNS) status (P = .012), number of severe infections (grade 3, 4 or 5) (P = .026) and serum albumin level (P = .032). Hypothyroidism was an independent prognostic factor for PFS in ALL children (P = .024, 95% CI: 1.1-4.1). We conclude that hypothyroidism is commonly present in ALL children during induction remission, which is related to chemotherapy drugs and severe infections. Hypothyroidism was a predictor of poor prognosis in childhood ALL.

Cystic fibrosis rabbits develop spontaneous hepatobiliary lesions and CF-associated liver disease (CFLD)-like phenotypes.

Cystic fibrosis (CF) is an autosomal recessive genetic disease affecting multiple organs. Approximately 30% CF patients develop CF-related liver disease (CFLD), which is the third most common cause of morbidity and mortality of CF. CFLD is progressive, and many of the severe forms eventually need liver transplantation. The mechanistic studies and therapeutic interventions to CFLD are unfortunately very limited. Utilizing the CRISPR/Cas9 technology, we recently generated CF rabbits by introducing mutations to the rabbit CF transmembrane conductance regulator (CFTR) gene. Here we report the liver phenotypes and mechanistic insights into the liver pathogenesis in these animals. CF rabbits develop spontaneous hepatobiliary lesions and abnormal biliary secretion accompanied with altered bile acid profiles. They exhibit nonalcoholic steatohepatitis (NASH)-like phenotypes, characterized by hepatic inflammation, steatosis, and fibrosis, as well as altered lipid profiles and diminished glycogen storage. Mechanistically, our data reveal that multiple stress-induced metabolic regulators involved in hepatic lipid homeostasis were up-regulated in the livers of CF-rabbits, and that endoplasmic reticulum (ER) stress response mediated through IRE1α-XBP1 axis as well as NF-κB- and JNK-mediated inflammatory responses prevail in CF rabbit livers. These findings show that CF rabbits manifest many CFLD-like phenotypes and suggest targeting hepatic ER stress and inflammatory pathways for potential CFLD treatment.

A New Immunosuppressive Therapy for Very Severe Aplastic Anemia in Children with Autoantibodies.

OBJECTIVE: At present, a number of very severe aplastic anemia (VSAA) patients cannot receive hematopoietic stem cell transplantation (HSCT) or standard immunosuppressive therapy (IST) due to the high cost of therapy, shortage of sibling donors, and lack of resources to support the HSCT. In addition, some VSAA patients with autoantibodies have no life-threatening infections or bleeding at the time of initial diagnosis. Considering the disease condition, economics and other factors, the present study designed a new and relatively mild treatment strategy: cyclosporine A plus pulsed high-dose prednisone (CsA+HDP). METHODS: The present study retrospectively analyzed 11 VSAA patients, who were treated with CsA+HDP in our hospital from August 2017 to August 2019. RESULTS: The median follow-up time for these patients was 24.9 months. The overall response rate was 54.5% (6/11) at six months after the initiation of IST and 81.8% (9/11) at deadline. Five patients achieved complete remission and four patients met the criteria for partial response at the last follow-up. The median time to response for responders was 110 days. Three patients underwent HSCT due to the poor effect of CsA+HDP or to find a suitable transplant donor. Recurrence and clonal evolution were not found in any of these patients. The estimated 3-year overall survival rate and 3-year failure-free survival rate were 100.0% and 72.7%, respectively. In addition, the results revealed that the cyclosporine-prednisone-associated toxicity was mild and well-tolerated by most patients. CONCLUSION: The novel CsA+HDP regimen has good therapeutic effect and safety for VSAA patients with autoantibodies, who have no serious life-threatening infections or bleeding at the time of initial diagnosis.

The Status of Pediatric Patients With Hematologic Malignancy During COVID-19 Pandemic in Wuhan City, China.

Data regarding the epidemiologic characteristics and clinical features of pediatric hematologic patients are limited in this corona virus disease 2019 (COVID-19) crisis. We investigated the status of 113 pediatric hematologic patients in Wuhan union hospital during the COVID-19 pandemic from January 23 to March 10, 2020. All the patients had routine blood and biochemical examination, as well as chest computed tomography scans, and the nucleic acid, immunoglobulin G-immunoglobulin M combined antibodies tests for SARS-CoV-2. After admission, all patients were single-room isolated for 5 to 7 days. The results showed that only 1 (0.88%) child with leukemia was confirmed to have SARS-CoV-2 infection and 15 (13.2%) children were considered as suspected cases. Comparing to the nonsuspected patients, the suspected cases had lower white blood cell count, hemoglobin level, neutrophil count, serum calcium ion level and serum albumin concentration, as well as higher levels of C-reactive protein. All the suspected cases were ruled out of SARS-CoV-2 infection by twice negative tests for the virus. Therefore, the incidence of SARS-CoV-2 infection in hematologic malignancy children was low during the COVID-19 pandemic in China. COVID-19 got early detected and the virus spread out in the ward was effectively blocked by increasing test frequency and using single-room isolation for 5 to 7 days after admission.

Anthracycline Induced Cardiac Disorders in Childhood Acute Lymphoblastic Leukemia: A Single-Centre, Retrospective, Observational Study.

Anthracycline-associated cardiotoxicity is frequently seen in cancer survivors years after treatment, but it is rare in patients on chemotherapy. This study aimed to investigate the clinical characteristics of cardiac disorders in children with acute lymphoblastic leukemia (ALL) during chemotherapy. A retrospective case study was conducted in children with ALL, for whom electrocardiogram (ECG) and echocardiography (Echo) were regularly assessed before each course of chemotherapy. The cardiac disorders were diagnosed according to the Common Terminology Criteria for Adverse Events (CTCAE) Version 5.0. Binary logistic regression analysis was used to identify risk factors associated with cardiac disorders. There were 171 children eligible for the study, and 78 patients (45.61%) were confirmed as having cardiac disorders. The incidence of cardiac disorders was dependent upon the cumulative dose of daunorubicin (DNR) (p = 0.030, OR = 1.553, 95% CI: 1.005-3.108). Four patients (2.34%) presented with palpitation, chest pain, and persistent tachycardia, and they were cured or improved after medical intervention. A total of 74 patients (43.27%) had subclinical cardiac disorders confirmed by ECG or Echo. ECG abnormalities were commonly seen in the induction and continuation treatments, including arrhythmias (26, 15.20%), ST changes (24, 14.04%) and conduction disorders (4, 2.34%). Pericardial effusion (14, 8.19%), left ventricular hypertrophy (11, 6.43%), a widened pulmonary artery (5, 2.92%) and valvular insufficiency (5, 2.92%) suggested by Echo occurred after induction chemotherapy. Therefore, cardiac disorders with clinical manifestations are rare and need early intervention. Subclinical cardiac disorders are common but very hidden in children during ALL chemotherapy. Regular ECG and Echo could help paediatricians to identify and monitor patients with asymptomatic cardiac disorders earlier.

Phenotypes of CF rabbits generated by CRISPR/Cas9-mediated disruption of the CFTR gene.

Existing animal models of cystic fibrosis (CF) have provided key insights into CF pathogenesis but have been limited by short lifespans, absence of key phenotypes, and/or high maintenance costs. Here, we report the CRISPR/Cas9-mediated generation of CF rabbits, a model with a relatively long lifespan and affordable maintenance and care costs. CF rabbits supplemented solely with oral osmotic laxative had a median survival of approximately 40 days and died of gastrointestinal disease, but therapeutic regimens directed toward restoring gastrointestinal transit extended median survival to approximately 80 days. Surrogate markers of exocrine pancreas disorders were found in CF rabbits with declining health. CFTR expression patterns in WT rabbit airways mimicked humans, with widespread distribution in nasal respiratory and olfactory epithelia, as well as proximal and distal lower airways. CF rabbits exhibited human CF-like abnormalities in the bioelectric properties of the nasal and tracheal epithelia. No spontaneous respiratory disease was detected in young CF rabbits. However, abnormal phenotypes were observed in surviving 1-year-old CF rabbits as compared with WT littermates, and these were especially evident in the nasal respiratory and olfactory epithelium. The CF rabbit model may serve as a useful tool for understanding gut and lung CF pathogenesis and for the practical development of CF therapeutics.

High-Dose Methotrexate-Induced Idiopathic Intracranial Hypertension in Infant Acute Lymphoblastic Leukemia.

A 7-month-old baby girl with acute lymphoblastic leukemia (ALL) presented with bulging anterior fontanelle after completing the first and second courses of high-dose methotrexate (HD-MTX) chemotherapy. Between courses, the infant recovered and was discharged. Prior to the third and fourth HD-MTX courses, the baby girl was administered infusions of dexamethasone, which prevented recurrence of neurological side effects observed after the first and second courses of HD-MTX. To our knowledge, this is the first reported case of HD-MTX-induced idiopathic intracranial hypertension in infants, and that prophylactic use of dexamethasone can be applied to prevent acute intracranial hypertension following HD-MTX infusion.

Huaier extract enhances the treatment efficacy of imatinib in Ik6+ Ph+ acute lymphoblastic leukemia.

Philadelphia chromosome-positive (Ph+) is considered as a high risk of acute lymphoblastic leukemia (ALL). Tyrosine kinase inhibitors (TKIs) are tailored drug for Ph+ ALL, but Ik6 is associated with TKI resistance and poor outcome of Ph+ ALL. In the present study, we investigated the potential benefit of combination therapy with imatinib and Huaier extract, a traditional Chinese medicine, in Ik6+ Ph+ ALL. The Ik6+ Ph+ -ALL cell lines Sup-B15 or BV173 were treated with Huaier extract, imatinib or the combination of the two. Analysis of cell proliferation showed that the combined treatment of imatinib and Huaier extract exhibited a greater effect on cell inhibition. Using flow cytometry and Western blot, enhanced effects on the induction of cell apoptosis were observed. The combination of the two drugs also exhibited a significant effect in decreasing the protein and enzymatic activity levels of BCR-ABL. The molecular mechanisms may be involved in BCR-ABL related pathways, including the inactivation of p-AKT, p-STAT5, p-mTOR and p-Lyn. Consistent with the in vitro results, the combination of Huaier extract and imatinib inhibit the growth and infiltration of xenografted tumors. Taken together, our findings show that Huaier extract enhances the anticancer efficacy of imatinib in Ik6+ Ph+ ALL Further, it also provides a potential clinical application in the treatment of refractory Ph+ ALL.

Correction: A photo-inducible protein-inorganic nanoparticle assembly for active targeted tumour theranostics.

Correction for 'A photo-inducible protein-inorganic nanoparticle assembly for active targeted tumour theranostics' by Jinbing Xie, Gang Han et al., Nanoscale, 2019, 11, 6136-6144.

A photo-inducible protein-inorganic nanoparticle assembly for active targeted tumour theranostics.

The assembly of protein-inorganic nanoparticles is an important yet challenging approach that is utilized to develop functional materials in numerous areas, such as bio-catalysis, drug delivery, and biosensing. In this study, we report on a facile, photo-inducible self-assembly method to generate protein-inorganic hybrid nanoplatforms. More specifically, photo-treated disulfide bond rich proteins of lysozyme (LYS) were able to be used as host materials in order to encapsulate nanoparticles (i.e., as-synthesized hydrophobic NIR quantum dots (QDs)) and anti-cancer small molecule drugs (i.e., paclitaxel (PTX)), constructing functional theranostic protein-inorganic hybrid nanoparticles. The modification of the functional polymer of cRGD-PEG contributes to the active tumour targeting characteristic of this protein-inorganic nanocarrier. This novel PTX loaded protein-inorganic hybrid nanoplatform showed high tumour homing accumulation as well as effective tumour inhibition. We believe that this general approach represents a new direction for the development of a photo-induced assembly of protein-inorganic nanoparticles towards versatile applications in both materials science and biomedical fields.

Regulation of hepatic autophagy by stress-sensing transcription factor CREBH.

Autophagy, a lysosomal degradative pathway in response to nutrient limitation, plays an important regulatory role in lipid homeostasis upon energy demands. Here, we demonstrated that the endoplasmic reticulum-tethered, stress-sensing transcription factor cAMP-responsive element-binding protein, hepatic-specific (CREBH) functions as a major transcriptional regulator of hepatic autophagy and lysosomal biogenesis in response to nutritional or circadian signals. CREBH deficiency led to decreased hepatic autophagic activities and increased hepatic lipid accumulation upon starvation. Under unfed or during energy-demanding phases of the circadian cycle, CREBH is activated to drive expression of the genes encoding the key enzymes or regulators in autophagosome formation or autophagic process, including microtubule-associated protein 1B-light chain 3, autophagy-related protein (ATG)7, ATG2b, and autophagosome formation Unc-51 like kinase 1, and the genes encoding functions in lysosomal biogenesis and homeostasis. Upon nutrient starvation, CREBH regulates and interacts with peroxisome proliferator-activated receptor α (PPARα) and PPARγ coactivator 1α to synergistically drive expression of the key autophagy genes and transcription factor EB, a master regulator of lysosomal biogenesis. Furthermore, CREBH regulates rhythmic expression of the key autophagy genes in the liver in a circadian-dependent manner. In summary, we identified CREBH as a key transcriptional regulator of hepatic autophagy and lysosomal biogenesis for the purpose of maintaining hepatic lipid homeostasis under nutritional stress or circadian oscillation.-Kim, H., Williams, D., Qiu, Y., Song, Z., Yang, Z., Kimler, V., Goldberg, A., Zhang, R., Yang, Z., Chen, X., Wang, L., Fang, D., Lin, J. D., Zhang, K. Regulation of hepatic autophagy by stress-sensing transcription factor CREBH.

Cooperation of IRAK1/4 inhibitor and ABT-737 in nanoparticles for synergistic therapy of T cell acute lymphoblastic leukemia.

T cell acute lymphoblastic leukemia (T-ALL) is caused by clonal expansion of variant T cell progenitors and is considered as a high risk leukemia. Contemporary single chemotherapy has a limited effect due to dynamic and versatile properties of T-ALL. Here IRAK1/4 inhibitor and ABT-737 were co-encapsulated into polyethylene glycol modified poly (lactic-co-glycolic acid) nanoparticles (IRAK/ABT-NP) to enhance synergistic therapy of T-ALL. The formulation was optimized to achieve high drug loading using Box-Behnken design and response surface methodology. The optimal parameter comprised 2.98% polymer in acetonitrile, a ratio of oil phase to water phase of 1:8.33, and 2.12% emulsifier concentration. High drug loading and uniform spherical shape was achieved. In vitro release study showed sustained release of IRAK1/4 inhibitor for 72 hours as well as sustained release of ABT-737 for more than 120 hours. Uptake efficiency of IRAK/ABT-NP and induced apoptotic T-ALL fraction by IRAK/ABT-NP were much higher than the IRAK1/4 and ABT-737 combined solution. IC50 of IRAK/ABT-NP was two-fold lower than free drug combination in Jurkat cells. Additionally, we conducted in vivo experiments in which IRAK/ABT-NP exhibited greater cytotoxicity toward T-ALL cells, the capacity to significantly restore white blood cell number in peripheral blood, and improved survival time of T-ALL mouse model compared to the IRAK1/4 and ABT-737 combined solution.

Trisomy 21 with t(5; 11) chromosomal translocation as new unfavorable cytogenetic abnormalities in pediatric acute myeloid leukemia type M2: One case report of nine-year follow-up and literature review.

We report one case of pediatric acute myeloid leukemia type 2 (AML-M2) who presented with karyotypic aberration of trisomy 21 with the t(5;11) chromosomal translocation. The patient achieved complete remission after two cycles of chemotherapy of daunorubicin, cytarabine and etoposide. Then, follow-up cytogenetic analysis from bone marrow cell cultures demonstrated a normal karyotype of 46, XY. After 9 years, the patient relapsed and the karyotypic abnormalities of trisomy 21 with t(5;11) reappeared. It was concluded that trisomy 21 with t(5; 11) is a new unfavorable cytogenetic aberration in AML-M2.

Inositol-Requiring Enzyme 1 Facilitates Diabetic Wound Healing Through Modulating MicroRNAs.

Diabetic skin ulcers represent a challenging clinical problem with mechanisms not fully understood. In this study, we investigated the role and mechanism for the primary unfolded protein response (UPR) transducer inositol-requiring enzyme 1 (IRE1α) in diabetic wound healing. Bone marrow-derived progenitor cells (BMPCs) were isolated from adult male type 2 diabetic and their littermate control mice. In diabetic BMPCs, IRE1α protein expression and phosphorylation were repressed. The impaired diabetic BMPC angiogenic function was rescued by adenovirus-mediated expression of IRE1α but not by the RNase-inactive IRE1α or the activated X-box binding protein 1 (XBP1), the canonical IRE1α target. In fact, IRE1α RNase processes a subset of microRNAs (miRs), including miR-466 and miR-200 families, through which IRE1α plays an important role in maintaining BMPC function under the diabetic condition. IRE1α attenuated maturation of miR-466 and miR-200 family members at precursor miR levels through the regulated IRE1α-dependent decay (RIDD) independent of XBP1. IRE1α deficiency in diabetes resulted in a burst of functional miRs from miR-466 and miR-200 families, which directly target and repress the mRNA encoding the angiogenic factor angiopoietin 1 (ANGPT1), leading to decreased ANGPT1 expression and disrupted angiogenesis. Importantly, cell therapies using IRE1α-expressing BMPCs or direct IRE1α gene transfer significantly accelerated cutaneous wound healing in diabetic mice through facilitating angiogenesis. In conclusion, our studies revealed a novel mechanistic basis for rescuing angiogenesis and tissue repair in diabetic wound treatments.

COX7AR is a Stress-inducible Mitochondrial COX Subunit that Promotes Breast Cancer Malignancy.

Cytochrome c oxidase (COX), the terminal enzyme of the mitochondrial respiratory chain, plays a key role in regulating mitochondrial energy production and cell survival. COX subunit VIIa polypeptide 2-like protein (COX7AR) is a novel COX subunit that was recently found to be involved in mitochondrial supercomplex assembly and mitochondrial respiration activity. Here, we report that COX7AR is expressed in high energy-demanding tissues, such as brain, heart, liver, and aggressive forms of human breast cancer cells. Under cellular stress that stimulates energy metabolism, COX7AR is induced and incorporated into the mitochondrial COX complex. Functionally, COX7AR promotes cellular energy production in human mammary epithelial cells. Gain- and loss-of-function analysis demonstrates that COX7AR is required for human breast cancer cells to maintain higher rates of proliferation, clone formation, and invasion. In summary, our study revealed that COX7AR is a stress-inducible mitochondrial COX subunit that facilitates human breast cancer malignancy. These findings have important implications in the understanding and treatment of human breast cancer and the diseases associated with mitochondrial energy metabolism.