A half sandwich Ru(II)-p-cymene nitrite complex selectively induces cell death in cisplatin-resistant malignant melanoma cells.

The Ru(II)-nitrite complex, Ru4, is explored to release nitric oxide (NO) under acidic conditions and selectively induce a cytotoxic effect towards SK-MEL-28 cisplatin-resistant malignant melanoma cells. These findings suggest that targeting the tumor-associated pHe level could be an effective strategy for the drug function of Ru(II)-nitrite compounds.

Indocyanine-Green-Loaded Liposomes for Photodynamic and Photothermal Therapies: Inducing Apoptosis and Ferroptosis in Cancer Cells with Implications beyond Oral Cancer.

Oral cancer represents a global health burden, necessitating novel therapeutic strategies. Photodynamic and photothermal therapies using indocyanine green (ICG) have shown promise due to their distinctive near-infrared (NIR) light absorption characteristics and FDA-approved safety profiles. This study develops ICG-loaded liposomes (Lipo-ICGs) to further explore their potential in oral cancer treatments. We synthesized and characterized the Lipo-ICGs, conducted in vitro cell culture experiments to assess cellular uptake and photodynamic/photothermal effects, and performed in vivo animal studies to evaluate their therapeutic efficacy. Quantitative cell apoptosis and gene expression variation were further characterized using flow cytometry and RNA sequencing, respectively. Lipo-ICGs demonstrated a uniform molecular weight distribution among particles. The in vitro studies showed a successful internalization of Lipo-ICGs into the cells and a significant photodynamic treatment effect. The in vivo studies confirmed the efficient delivery of Lipo-ICGs to tumor sites and successful tumor growth inhibition following photodynamic therapy. Moreover, light exposure induced a time-sensitive photothermal effect, facilitating the further release of ICG, and enhancing the treatment efficacy. RNA sequencing data showed significant changes in gene expression patterns upon Lipo-ICG treatment, suggesting the activation of apoptosis and ferroptosis pathways. The findings demonstrate the potential of Lipo-ICGs as a therapeutic tool for oral cancer management, potentially extending to other cancer types.

Plasma and Urinary Platelet Factor 4 as Biomarkers for Cardiovascular Risk in Children with Chronic Kidney Disease.

Children suffering from chronic kidney disease (CKD) have a high risk of cardiovascular disease (CVD). The early detection and diagnosis of subclinical CVD in pediatric CKD can reduce mortality later in life. Plasma factor 4 (PF4) is a chemokine released by activated platelets. We examined whether or not PF4 in the plasma and urine, its kidney function normalized ratio, and fractional excretion have differential associations with CVD risk markers in 139 youths aged 3 to 18 years old with CKD stages G1-G4. Significant negative correlations were observed between plasma PF4 and cardiovascular surrogate markers, such as the left ventricular mass index (LVMI), carotid intima-media thickness (cIMT), and pulse wave velocity (PWV). The plasma PF4/creatinine (Cr) ratio was lower in CKD children with a high daytime BP and 24 h BP, high BP load, and nocturnal non-dipping status. After adjusting for confounders, the plasma PF4 and plasma PF4/Cr ratio still independently predicted an abnormal ABPM profile. In addition, both the plasma PF4 and plasma PF4/Cr ratio presented a negative correlation with the L-arginine and asymmetric dimethylarginine ratio. These findings provide convincing evidence supporting the link between PF4 and CVD markers in pediatric CKD. Our study highlights the importance of further research to assess the performance of PF4-related biomarkers in predicting CVD events and CKD progression in children with CKD.

CBAP regulates the function of Akt-associated TSC protein complexes to modulate mTORC1 signaling.

The Akt-Rheb-mTORC1 pathway plays a crucial role in regulating cell growth, but the mechanisms underlying the activation of Rheb-mTORC1 by Akt remain unclear. In our previous study, we found that CBAP was highly expressed in human T-ALL cells and primary tumors, and its deficiency led to reduced phosphorylation of TSC2/S6K1 signaling proteins as well as impaired cell proliferation and leukemogenicity. We also demonstrated that CBAP was required for Akt-mediated TSC2 phosphorylation in vitro. In response to insulin, CBAP was also necessary for the phosphorylation of TSC2/S6K1 and the dissociation of TSC2 from the lysosomal membrane. Here we report that CBAP interacts with AKT and TSC2, and knockout of CBAP or serum starvation leads to an increase in TSC1 in the Akt/TSC2 immunoprecipitation complexes. Lysosomal-anchored CBAP was found to override serum starvation and promote S6K1 and 4EBP1 phosphorylation and c-Myc expression in a TSC2-dependent manner. Additionally, recombinant CBAP inhibited the GAP activity of TSC2 complexes in vitro, leading to increased Rheb-GTP loading, likely due to the competition between TSC1 and CBAP for binding to the HBD domain of TSC2. Overexpression of the N26 region of CBAP, which is crucial for binding to TSC2, resulted in a decrease in mTORC1 signaling and an increase in TSC1 association with the TSC2/AKT complex, ultimately leading to increased GAP activity toward Rheb and impaired cell proliferation. Thus, we propose that CBAP can modulate the stability of TSC1-TSC2 as well as promote the translocation of TSC1/TSC2 complexes away from lysosomes to regulate Rheb-mTORC1 signaling.

Arsenic exposure and lung fibrotic changes-evidence from a longitudinal cohort study and experimental models.

Introduction: Arsenic (As) exposure is associated with lung toxicity and we aim to investigate the effects of arsenic exposure on lung fibrotic changes. Methods: Participants (n= 976) enrolled via a general health survey underwent chest low-dose computed tomography (LDCT), spirometry forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and urinary arsenic examination during 2016 and 2018. Lung fibrotic changes from LDCT were defined. AsLtoL, low arsenic levels in both 2016 and 2018; AsLtoH, low arsenic in 2016 but high levels in 2018; AsHtoL, high arsenic in 2016 but low levels in 2018; AsHtoH, high arsenic levels in both 2016 and 2018. Mice exposed to 0. 0.2mg/L, 2 mg/L, 50 mg/L of sodium arsenite (NaAsO2) through drinking water for 12 weeks and 24 weeks were applied for histological analysis. Cultured lung epithelial cells were exposed to NaAsO2 and the mesenchymal changes were examined. Results: AsHtoH increased the risk (OR= 1.65, 95% CI 1.10, 2.49) of Lung fibrotic positive to positive (reference: Lung fibrotic negative to negative) compared with AsLtoL. Moreover, the predicted mean of FVC and FEV1 in AsHtoH (-0.09 units, 95% CI: -0.27, -0.09; -0.09 units, 95% CI: -0.17, -0.01) and AsLtoH (-0.13 units, 95% CI: -0.30, -0.10; -0.13 units, 95% CI: -0.22, -0.04) was significantly lower than ASLtoL. Significant lung fibrotic changes including the increase of the alveolar septum thickness and collagen fiber deposition were observed upon 2 mg/L NaAsO2 treatment for 12 weeks, and the damage was dose- and time-dependent. In vitro, sodium arsenite treatment promotes the epithelial-mesenchymal transition (EMT)-like changes of the normal human bronchial epithelial cells, including upregulation of several fibrotic and mesenchymal markers (fibronectin, MMP-2, and Snail) and cell migration. Inhibition of reactive oxygen species (ROS) and MMP-2 impaired the arsenic-induced EMT changes. Administration of a flavonoid, apigenin, inhibited EMT in vitro and pulmonary damages in vivo with the reduction of mesenchymal markers. Discussion: we demonstrated that continued exposure to arsenic causes lung fibrosis in humans and mice. Targeting lung epithelial cells EMT is effective on the development of therapeutic strategy. Apigenin is effective in the inhibition of arsenic-induced pulmonary fibrosis and EMT.

Pregnancy Zone Protein as an Emerging Biomarker for Cardiovascular Risk in Pediatric Chronic Kidney Disease.

Cardiovascular disease (CVD) is a significant cause of mortality and morbidity among children with chronic kidney disease (CKD). The causes of pediatric CKD differ from those in adults, as congenital anomalies in the kidney and urinary tract (CAKUT) are the leading causes in childhood. Identifying ideal markers of CVD risk early is crucial for CKD children to improve their care. Previously, we screened differentially expressed proteins in CKD children with or without blood pressure (BP) abnormalities and identified pregnancy zone protein (PZP). In 106 children and adolescents with CKD stages G1-G4, we analyzed plasma PZP concentration. The associations between PZP and ambulatory BP monitoring (ABPM) profile, parameters of cardiac and carotid ultrasounds, indices of arterial stiffness, and nitric oxide (NO) parameters were determined. We observed that PZP positively correlated with arterial stiffness indices, beta index, and pulse wave velocity in CAKUT. CKD children with abnormalities in ABPM and night dipping displayed a higher PZP concentration than those without. Additionally, the PZP level was positively correlated with NO bioavailability. In conclusion, our results suggest PZP has differential influences on cardiovascular risk in CAKUT and non-CAKUT children. Identification of this relationship is novel in the pediatric CKD literature.

Di(2-ethylhexyl) phthalate mediates IL-33 production via aryl hydrocarbon receptor and is associated with childhood allergy development.

Background: Few studies assess cord blood biomarkers to predict prenatal exposure to di(2-ethylhexyl) phthalate (DEHP) on the development of allergic diseases later in childhood. IL-33 has been indicated to play an important role in allergic diseases. We evaluated the association of prenatal DEHP exposure and IL-33 in cord blood on the development of allergic diseases. We also investigated the mechanism of DEHP in human lung epithelial cells and asthma animal models. Methods: 66 pregnant women were recruited, and their children followed when they were aged 3 years. Maternal urinary DEHP metabolites were determined using liquid chromatography-electrospray-ionization-tandem mass spectrometry. The effect of DEHP on IL-33 production was investigated in human lung epithelial cells and club cell-specific aryl hydrocarbon receptor (AhR) deficiency mice. ELISA and RT-PCR, respectively, measured the IL-33 cytokine concentration and mRNA expression. Results: The concentrations of maternal urinary DEHP metabolites and serum IL-33 in cord blood with childhood allergy were significantly higher than those in the non-childhood allergy group. DEHP and MEHP could induce IL-33 production and reverse by AhR antagonist and flavonoids in vitro. Enhanced ovalbumin-induced IL-4 and IL-33 production in bronchoalveolar lavage fluid (BALF) by DEHP exposure and suppressed in club cell-specific AhR null mice. Kaempferol has significantly reversed the DEHP effect in the asthma animal model. Conclusions: Cord blood IL-33 level was correlated to childhood allergy and associated with maternal DEHP exposure. IL-33 might be a potential target to assess the development of DEHP-related childhood allergic disease. Flavonoids might be the natural antidotes for DEHP.

Targeting sphingosine 1-phosphate receptor 3 inhibits T-cell exhaustion and regulates recruitment of proinflammatory macrophages to improve antitumor efficacy of CAR-T cells against solid tumor.

BACKGROUNDS: Chimeric antigen receptor (CAR)-modified T cells (CAR-T) are limited in solid tumors due to the hostile tumor microenvironment (TME). Combination therapy could be a promising approach to overcome this obstacle. Recent studies have shown that sphingosine 1-phosphate receptor (S1PR)3 has tremendous potential in regulating the immune environment. However, the functional significance of S1PR3 in T-cell-based immunotherapies and the molecular mechanisms have not been fully understood. METHODS: Here, we studied the combination of EpCAM-specific CAR T-cell therapy with pharmacological blockade of S1PR3 against solid tumor. We have applied RNA sequencing, flow cytometry, ELISA, cellular/molecular immunological technology, and mouse models of solid cancers. RESULTS: Our study provided evidence that S1PR3 high expression is positively associated with resistance to programmed cell death protein-1 (PD-1)-based immunotherapy and increased T-cell exhaustion. In addition, pharmacological inhibition of S1PR3 improves the efficacy of anti-PD-1 therapy. Next, we explored the possible combination of S1PR3 antagonist with murine EpCAM-targeted CAR-T cells in immunocompetent mouse models of breast cancer and colon cancer. The results indicated that the S1PR3 antagonist could significantly enhance the efficacy of murine EpCAM CAR-T cells in vitro and in vivo. Mechanistically, the S1PR3 antagonist improved CAR-T cell activation, regulated the central memory phenotype, and reduced CAR-T cell exhaustion in vitro. Targeting S1PR3 was shown to remodel the TME through the recruitment of proinflammatory macrophages by promoting macrophage activation and proinflammatory phenotype polarization, resulting in improved CAR-T cell infiltration and amplified recruitment of CD8+T cells. CONCLUSIONS: This work demonstrated targeting S1PR3 could increase the antitumor activities of CAR-T cell therapy at least partially by inhibiting T-cell exhaustion and remodeling the TME through the recruitment of proinflammatory macrophages. These findings provided additional rationale for combining S1PR3 inhibitor with CAR-T cells for the treatment of solid tumor.

The Role of Macrophages in Connective Tissue Disease-Associated Interstitial Lung Disease: Focusing on Molecular Mechanisms and Potential Treatment Strategies.

Connective tissue disease-associated interstitial lung disease (CTD-ILD) is a severe manifestation of CTD that leads to significant morbidity and mortality. Clinically, ILD can occur in diverse CTDs. Pathologically, CTD-ILD is characterized by various histologic patterns, such as nonspecific interstitial pneumonia, organizing pneumonia, and usual interstitial pneumonia. Abnormal immune system responses have traditionally been instrumental in its pathophysiology, and various changes in immune cells have been described, especially in macrophages. This article first briefly overviews the epidemiology, clinical characteristics, impacts, and histopathologic changes associated with CTD-ILD. Next, it summarizes the roles of various signaling pathways in macrophages or products of macrophages in ILD, helped by insights gained from animal models. In the following sections, this review returns to studies of macrophages in CTD-ILD in humans for an overall picture of the current understanding. Finally, we direct attention to potential therapies targeting macrophages in CTD-ILD in investigation or in clinical trials, as well as the future directions regarding macrophages in the context of CTD-ILD. Although the field of macrophages in CTD-ILD is still in its infancy, several lines of evidence suggest the potential of this area.

Vogt-Koyanagi-Harada disease in pediatric, adult and elderly: clinical characteristics and visual outcomes.

PURPOSE: To depict a whole spectrum of clinical feartures and visual prognosis among pediatric, adult, and elderly Vogt-Koyanagi-Harada disease (VKH) patients. METHODS: Retrospective chart review was conducted in 2571 VKH patients diagnosed from April 2008 to January 2022. Based on age of disease onset, patients were divided into pediatric (age ≤ 16 years), adult (16 < age < 65 years), and elderly (age ≥ 65 years) VKH group. Ocular and extraocular manifestations were compared among these patients. Visual outcomes and complications were evaluated using logistic regression models and restricted cubic splines analysis. RESULTS: The median follow-up time was 48 (IQR, 12-60) months. Pediatric, adult and elderly VKH were found in 106 (4.1%), 2355 (91.6%), and 110 (4.3%) patients, respectively. All of the patients showed similar ocular manifestations in the context of disease phasing. The proportion of neurological and auditory manifestations in pediatric (42.3% and 7.5%) VKH patients was significantly lower than that in adults (66.5% and 47.9%) and elderly (68.2% and 50%) (both p < 0.0001). An increased risk of macular abnormalities was seen in adults (OR, 3.43; 95% CI, 1.62-7.29) compared with elderly VKH. An inverted-U-shaped pattern was observed between disease onset age and a poor visual outcome (visual acuity 6/18 or worse) according to OR value in VKH patients. The highest risk of BCVA ≤ 6/18 was observed in 32 years at disease onset (OR, 1.51; 95% CI, 1.18-1.94). A higher risk of visual loss was observed in adult VKH patients (OR, 9.06; 95% CI, 2.18-37.6) compared with elderly VKH patients. And stratified by macular abnormalities, the interaction test was not significant (P = 0.634). CONCLUSION: Our study identified, for the first time, a whole spectrum of clinical features of VKH based on a large cohort of Chinese patients. Adult VKH patients have an increased risk of poor visual outcomes, possibly due to increased frequency of macular abnormalities.

Optimized CAR-T therapy based on spatiotemporal changes and chemotactic mechanisms of MDSCs induced by hypofractionated radiotherapy.

Poor intratumoral infiltration is the major challenge for chimeric antigen receptor (CAR)-T cell therapy in solid tumors. Hypofractionated radiotherapy (HFRT) has been reported to induce immune cell infiltration and reshape the tumor immune microenvironment. Here, we showed that HFRT (5 × 5 Gy) mediated an early accumulation of intratumoral myeloid-derived suppressor cells (MDSCs) and decreased infiltration of T cells in the tumor microenvironment (TME) of immunocompetent mice bearing triple-negative breast cancer (TNBC) or colon cancer, which was further confirmed in tumors from patients. RNA sequencing (RNA-seq) and cytokine profiling analysis revealed that HFRT induced the activation and proliferation of tumor-infiltrated MDSCs, which was mediated by the interactions of multiple chemokines and chemokine receptors. Further investigation showed that when combined with HFRT, CXCR2 blockade significantly inhibited MDSCs trafficking to tumors and effectively enhanced the intratumoral infiltration and treatment efficacy of CAR-T cells. Our study demonstrates that MDSCs blockade combined with HFRT is promising for CAR-T cell therapy optimization in solid tumors.

The Role of Exosomes in Pancreatic Ductal Adenocarcinoma Progression and Their Potential as Biomarkers.

Pancreatic ductal adenocarcinoma (PDAC), the most common pancreatic malignancy, is an aggressive and lethal cancer with a dismal five-year survival rate. Despite remarkable improvements in cancer therapeutics, the clinical outcome of PDAC patients remains poor due to late diagnosis of the disease. This highlights the importance of early detection, wherein biomarker evaluation including exosomes would be helpful. Exosomes, small extracellular vesicles (sEVs), are cell-secreted entities with diameters ranging from 50 to 150 nm that deliver cellular contents (e.g., proteins, lipids, and nucleic acids) from parent cells to regulate the cellular processes of targeted cells. Recently, an increasing number of studies have reported that exosomes serve as messengers to facilitate stromal-immune crosstalk within the PDAC tumor microenvironment (TME), and their contents are indicative of disease progression. Moreover, evidence suggests that exosomes with specific surface markers are capable of distinguishing patients with PDAC from healthy individuals. Detectable exosomes in bodily fluids (e.g., blood, urine, saliva, and pancreatic juice) are omnipresent and may serve as promising biomarkers for improving early detection and evaluating patient prognosis. In this review, we shed light on the involvement of exosomes and their cargos in processes related to disease progression, including chemoresistance, angiogenesis, invasion, metastasis, and immunomodulation, and their potential as prognostic markers. Furthermore, we highlight feasible clinical applications and the limitations of exosomes in liquid biopsies as tools for early diagnosis as well as disease monitoring. Taking advantage of exosomes to improve diagnostic capacity may provide hope for PDAC patients, although further investigation is urgently needed.

Early vs Deferred Non-Messenger RNA COVID-19 Vaccination Among Chinese Patients With a History of Inactive Uveitis: A Randomized Clinical Trial.

Importance: Improper host response to COVID-19 vaccines could trigger immune-mediated adverse events. The question remains whether COVID-19 vaccination should be postponed until complete remission in patients with uveitis, a preexisting immune-related condition. Objective: To compare recommendations for early and deferred COVID-19 vaccination with respect to uveitis outcomes. Design, Setting, and Participants: This open-label, randomized clinical trial at a large, specialized teaching center for uveitis care in China enrolled unvaccinated patients with inactive uveitis between August 10, 2021, and February 22, 2022, with follow-up to June 6, 2022. Interventions: Participants were randomly assigned to receive recommendation for early or deferred COVID-19 vaccination after complete remission of uveitis. Non-messenger RNA (non-mRNA) COVID-19 vaccines were available in China during the trial. Main Outcomes and Measures: The primary outcome was the time to symptomatic uveitis worsening during 3 months of follow-up. Secondary outcomes included uveitis activity and best-corrected visual acuity at 3 months. Results: Of the 543 participants (304 women [56.0%]; median age, 35 [IQR, 26-49] years), 262 were recommended for early vaccination and 281 for deferred vaccination. By month 3, 109 patients (41.6%) in the early group had been vaccinated compared with 14 (5.0%) in the deferred recommendation group. In the intention-to-treat population, the time to symptomatic uveitis worsening was shorter in the early group than in the deferred group (hazard ratio, 1.68 [95% CI, 1.09-2.59]; P = .01 by log-rank test). Changes in anterior chamber cells, vitreous haze, and best-corrected visual acuity from baseline to month 3 appeared similar in the 2 groups in the evaluable population after the month 3 in-person visit. Conclusions and Relevance: In this randomized clinical trial of patients with inactive uveitis, recommendation for early non-mRNA COVID-19 vaccination resulted in a higher incidence of self-reported symptomatic uveitis worsening with possible reporting bias compared with recommendation for deferred vaccination, but no adverse effects were observed in disease and visual prognosis at 3 months. These findings would be useful to guide the individual timing choices of non-mRNA COVID-19 vaccination in this clinically vulnerable population. Trial Registration: Chinese Clinical Trial Registry: ChiCTR2100049467.

Circulating gamma-glutamyl transpeptidase and risk of pancreatic cancer: A prospective cohort study in the UK Biobank.

BACKGROUND: To determine whether serum gamma-glutamyl transpeptidase (GGT) level is associated with pancreatic cancer risk in a large prospective cohort. METHODS: The study analyzed serum GGT concentration at baseline of 421,032 participants recruited in the UK Biobank since 2006 through 2010. Information on incidence of pancreatic cancer was obtained from cancer and death registers, updated until 2015 in Scotland or 2016 in England and Wales. Adjusted Cox proportional hazards models were used to measure the association between serum GGT and pancreatic cancer risk. RESULTS: The study identified 586 cases of pancreatic cancer over a median follow-up period of 7.16 years. In the multivariable-adjusted Cox model, serum GGT level was associated with 14% higher pancreatic cancer risk (hazard ratio (HR) per one standard deviation increment of log2 GGT level = 1.14, 95% confidence interval (CI) 1.02-1.28, p = 0.025). In the total population, the HR for the highest GGT group was 1.68 (95%CI: 1.22-2.30) versus the lowest GGT group. The HR for the highest GGT group in men (≥50.2 U/L) was 1.72 (95%CI: 1.14-2.61) and that in women (≥31.6 U/L) was 1.75 (95%CI: 1.06-2.88) versus the lowest GGT group. CONCLUSION: Our findings suggested a positive association of serum GGT in pancreatic cancer etiology, implying the potential of monitoring GGT level for identifying at-risk individuals for pancreatic cancer.

Indocyanine green as a near-infrared theranostic agent for ferroptosis and apoptosis-based, photothermal, and photodynamic cancer therapy.

Ferroptosis is a recently discovered programmed cell death pathway initiated by reactive oxygen species (ROS). Cancer cells can escape ferroptosis, and strategies to promote cancer treatment are crucial. Indocyanine green (ICG) is a near-infrared (NIR) fluorescent molecule used in the imaging of residual tumor removal during surgery. Growing attention has been paid to the anticancer potential of ICG-NIR irradiation by inducing ROS production and theranostic effects. Organic anion transmembrane polypeptide (OATP) 1B3 is responsible for ICG metabolism. Additionally, the overexpression of OATP1B3 has been reported in several cancers. However, whether ICG combined with NIR exposure can cause ferroptosis remains unknown and the concept of treating OATP1B3-expressing cells with ICG-NIR irradiation has not been validated. We then used ICG as a theranostic molecule and an OATP1B3-transfected fibrosarcoma cell line, HT-1080 (HT-1080-OATP1B3), as a cell model. The HT-1080-OATP1B3 cell could promote the uptake of ICG into the cytoplasm. We observed that the HT-1080-OATP1B3 cells treated with ICG and exposed to 808-nm laser irradiation underwent apoptosis, as indicated by a reduction in mitochondrial membrane potential, and upregulation of cleaved Caspase-3 and Bax but downregulation of Bcl-2 expression. Moreover, lipid ROS production and consequent ferroptosis and hyperthermic effect were noted after ICG and laser administration. Finally, in vivo study findings also revealed that ICG with 808-nm laser irradiation has a significant effect on cancer suppression. ICG is a theranostic molecule that exerts synchronous apoptosis, ferroptosis, and hyperthermia effects and thus can be used in cancer treatment. Our findings may facilitate the development of treatment modalities for chemo-resistant cancers.

Arsenic Induces M2 Macrophage Polarization and Shifts M1/M2 Cytokine Production via Mitophagy.

Arsenic is an environmental factor associated with epithelial-mesenchymal transition (EMT). Since macrophages play a crucial role in regulating EMT, we studied the effects of arsenic on macrophage polarization. We first determined the arsenic concentrations to be used by cell viability assays in conjunction with previous studies. In our results, arsenic treatment increased the alternatively activated (M2) macrophage markers, including arginase 1 (ARG-1) gene expression, chemokine (C-C motif) ligand 16 (CCL16), transforming growth factor-ß1 (TGF-ß1), and the cluster of differentiation 206 (CD206) surface marker. Arsenic-treated macrophages promoted A549 lung epithelial cell invasion and migration in a cell co-culture model and a 3D gel cell co-culture model, confirming that arsenic treatment promoted EMT in lung epithelial cells. We confirmed that arsenic induced autophagy/mitophagy by microtubule-associated protein 1 light-chain 3-II (LC3 II) and phosphor-Parkin (p-Parkin) protein markers. The autophagy inhibitor chloroquine (CQ) recovered the expression of the inducible nitric oxide synthase (iNOS) gene in arsenic-treated M1 macrophages, which represents a confirmation that arsenic indeed induced the repolarization of classically activated (M1) macrophage to M2 macrophages through the autophagy/mitophagy pathway. Next, we verified that arsenic increased M2 cell markers in mouse blood and lungs. This study suggests that mitophagy is involved in the arsenic-induced M1 macrophage switch to an M2-like phenotype.