VHL governs m6A modification and PIK3R3 mRNA stability in clear cell renal cell carcinomas.

N6-Methyladenosine (m6A), a prevalent posttranscriptional modification, plays an important role in cancer progression. Clear cell renal cell carcinoma (ccRCC) is chiefly associated with the loss of the von Hippel-Lindau (VHL) gene, encoding a component of the E3 ubiquitin ligase complex. In this issue of the JCI, Zhang and colleagues unveiled a function of VHL beyond its canonical role as an E3 ubiquitin ligase in regulating hypoxia-inducible factors (HIFs). It also governed m6A modification by orchestrating the assembly of m6A writer proteins METTL3 and METTL14, thereby stabilizing PIK3R3 mRNA. Mechanistically, PIK3R3 contributed to p85 ubiquitination, which restrained PI3K/AKT signaling and consequently impeded ccRCC growth in cell and mouse models. This discovery provides potential treatment targets in VHL-deficient ccRCCs.

Factors Associated With Radiological Lung Growth Rate After Lobectomy in Patients With Lung Cancer.

INTRODUCTION: This study is a retrospective study. This study aims to explore the association between lobectomy in lung cancer patients and subsequent compensatory lung growth (CLG), and to identify factors that may be associated with variations in CLG. METHODS: 207 lung cancer patients who underwent lobectomy at Yunnan Cancer Hospital between January 2020 and December 2020. All patients had stage IA primary lung cancer and were performed by the same surgical team. And computed tomography examinations were performed before and 1 y postoperatively. Based on computed tomography images, the volume of each lung lobe was measured using computer software and manual, the radiological lung weight was calculated. And multiple linear regressions were used to analyze the factors related to the increase in postoperative lung weight. RESULTS: One year after lobectomy, the radiological lung weight increased by an average of 112.4 ± 20.8%. Smoking history, number of resected lung segments, preoperative low attenuation volume, intraoperative arterial oxygen partial pressure/fraction of inspired oxygen ratio and postoperative visual analog scale scores at 48 h were significantly associated with postoperative radiological lung weight gain. CONCLUSIONS: Our results suggest that CLG have occurred after lobectomy in adults. In addition, anesthetists should maintain high arterial oxygen partial pressure/fraction of inspired oxygen ratio during one-lung ventilation and improve acute postoperative pain to benefit CLG.

The roles of ferroptosis in cancer: Tumor suppression, tumor microenvironment, and therapeutic interventions.

In cancer treatment, the recurrent challenge of inducing apoptosis through conventional therapeutic modalities, often thwarted by therapy resistance, emphasizes the critical need to explore alternative cell death pathways. Ferroptosis, an iron-dependent form of regulated cell death triggered by the lethal accumulation of lipid peroxides on cellular membranes, has emerged as one such promising frontier in oncology. Induction of ferroptosis not only suppresses tumor growth but also holds potential for augmenting immunotherapy responses and surmounting resistance to existing cancer therapies. This review navigates the role of ferroptosis in tumor suppression. Furthermore, we delve into the complex role of ferroptosis within the tumor microenvironment and its interplay with antitumor immunity, offering insights into the prospect of targeting ferroptosis as a strategic approach in cancer therapy.

The adverse impact of perioperative body composition abnormalities on outcomes after split liver transplantation: a multi-center retrospective cohort study.

BACKGROUND: Split liver transplantation increases graft availability, but its safe and effective utilization is insufficiently documented. This study aimed to investigate the association between perioperative body composition abnormalities and outcomes in adult split liver transplantation. MATERIALS AND METHODS: 240 recipients who underwent split liver transplantation in three centers were enrolled in this retrospective cohort study. Body composition abnormalities including sarcopenia, myosteatosis, visceral obesity, and sarcopenic obesity were evaluated at baseline and one month after surgery using computed tomography. Their impact on outcomes including early allograft dysfunction, early complications, intensive care unit stay, graft regeneration rate and survival was analyzed. RESULTS: Recipients with sarcopenia or myosteatosis had a higher risk of early allograft dysfunction, higher early complication rate, and longer length of intensive care unit stay (all P<0.05), while there was no difference in graft regeneration rate. Recipient and graft survival were significantly worse for recipients with body composition abnormalities (all P<0.05). In multivariable Cox-regression analysis, sarcopenia (hazard ratio=1.765, P=0.015), myosteatosis (hazard ratio=2.066, P=0.002), and visceral obesity (hazard ratio=1.863, P=0.008) were independently associated with shorter overall survival. Piling up of the three factors increased the mortality risk stepwise (P<0.001). Recipients experienced skeletal muscle loss and muscle fat infiltration one month after surgery. Postoperative worsening sarcopenia (hazard ratio=2.359, P=0.009) and myosteatosis (hazard ratio=1.878, P=0.026) were also identified as independent risk factors for mortality. CONCLUSION: Sarcopenia, myosteatosis and their progression negatively affect outcomes including early allograft dysfunction, early complications, intensive care unit stay and survival after SLT. Systemic evaluation and dynamic monitoring of body composition are valuable.

BRCA1-mediated dual regulation of ferroptosis exposes a vulnerability to GPX4 and PARP co-inhibition in BRCA1-deficient cancers.

Resistance to poly (ADP-ribose) polymerase inhibitors (PARPi) limits the therapeutic efficacy of PARP inhibition in treating breast cancer susceptibility gene 1 (BRCA1)-deficient cancers. Here we reveal that BRCA1 has a dual role in regulating ferroptosis. BRCA1 promotes the transcription of voltage-dependent anion channel 3 (VDAC3) and glutathione peroxidase 4 (GPX4); consequently, BRCA1 deficiency promotes cellular resistance to erastin-induced ferroptosis but sensitizes cancer cells to ferroptosis induced by GPX4 inhibitors (GPX4i). In addition, nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy and defective GPX4 induction unleash potent ferroptosis in BRCA1-deficient cancer cells upon PARPi and GPX4i co-treatment. Finally, we show that xenograft tumors derived from BRCA1-mutant breast cancer patients with PARPi resistance exhibit decreased GPX4 expression and high sensitivity to PARP and GPX4 co-inhibition. Our results show that BRCA1 deficiency induces a ferroptosis vulnerability to PARP and GPX4 co-inhibition and inform a therapeutic strategy for overcoming PARPi resistance in BRCA1-deficient cancers.

Metabolic cell death in cancer: Ferroptosis, cuproptosis, disulfidptosis, and beyond.

Cell death resistance represents a hallmark of cancer. Recent studies have identified metabolic cell death as unique forms of regulated cell death resulting from an imbalance in the cellular metabolism. This review discusses the mechanisms of metabolic cell death-ferroptosis, cuproptosis, disulfidptosis, lysozincrosis, and alkaliptosis-and explores their potential in cancer therapy. Our review underscores the complexity of the metabolic cell death pathways and offers insights into innovative therapeutic avenues for cancer treatment.

mTOR inhibitor reduces nontumour-related death in liver transplantation for hepatocellular carcinoma.

Sirolimus is a regularly applied immunosuppressant for patients undergoing liver transplantation (LT) for hepatocellular carcinoma (HCC). Sirolimus not only significantly inhibits HCC recurrence but also protects renal function. However, the improvement effect of sirolimus on nontumour-related death in patients is still unknown. The aim of our study was to investigate the therapeutic effect of sirolimus on nontumour-related deaths. In this study, we retrospectively enrolled 403 LT patients with HCC from January 1, 2015, to December 31, 2018. The median follow-up time was 47.1 months. The patients were divided into the sirolimus group (N = 184) and the sirolimus-free group (N = 219). There were no significant differences between the sirolimus group and the sirolimus-free group in survival (P = 0.054). In transplant patients who exceeded the Milan or Hangzhou criteria, the sirolimus group achieved higher survival than the sirolimus-free group (P = 0.005; P = 0.02). Moreover, multivariate analysis showed that sirolimus strongly reduced the hazard ratio (HR) for nontumour-related death in LT patients who exceeded the Milan (HR: 0.42; 95% CI: 0.18-1; P = 0.05) or Hangzhou criteria (HR: 0.26; 95% CI: 0.08-0.89; P = 0.032). HCC recurrence increased the risk of nontumour-related death. In conclusion, sirolimus-based immunosuppression can significantly reduce nontumour-related death in LT patients who exceed the criteria for transplantation. In addition, this finding will further promote the application of sirolimus after liver transplantation for hepatocellular carcinoma.

Post-transplant hepatitis B virus reactivation impacts the prognosis of patients with hepatitis B-related hepatocellular carcinoma: a dual-centre retrospective cohort study in China.

BACKGROUND: Highly active hepatitis B virus (HBV) is known to be associated with poor outcomes in patients with hepatocellular carcinoma (HCC). This study aims to investigate the relationship between HBV status and HCC recurrence after liver transplantation. METHODS: The study retrospectively analyzed HCC patients undergoing liver transplantation in two centres between January 2015 and December 2020. The authors reviewed post-transplant HBV status and its association with outcomes. RESULTS: The prognosis of recipients with hepatitis B surface antigen (HBsAg) reappearance ( n =58) was poorer than those with HBsAg persistent negative ( n =351) and positive ( n =53). In HBsAg persistent positive group, recipients with HBV DNA reappearance or greater than 10-fold increase above baseline had worse outcomes than those without ( P <0.01). HBV reactivation was defined as (a) HBsAg reappearance or (b) HBV DNA reappearance or greater than 10-fold increase above baseline. After propensity score matching, the 5-year overall survival rate and recurrence-free survival rate after liver transplantation in recipients with HBV reactivation were significantly lower than those without (32.0% vs. 62.3%; P <0.01, and 16.4% vs. 63.1%; P <0.01, respectively). Moreover, HBV reactivation was significantly related to post-transplant HCC recurrence, especially lung metastasis. Cox regression analysis revealed that beyond Milan criteria, microvascular invasion and HBsAg-positive graft were independent risk factors for post-transplant HBV reactivation, and a novel nomogram was established accordingly with a good predictive efficacy (area under the time-dependent receiver operating characteristic curve=0.78, C-index =0.73). CONCLUSIONS: Recipients with HBV reactivation had worse outcomes and higher tumour recurrence rates than those without. The nomogram could be used to evaluate the risk of post-transplant HBV reactivation effectively.

Cell cycle arrest induces lipid droplet formation and confers ferroptosis resistance.

How cells coordinate cell cycling with cell survival and death remains incompletely understood. Here, we show that cell cycle arrest has a potent suppressive effect on ferroptosis, a form of regulated cell death induced by overwhelming lipid peroxidation at cellular membranes. Mechanistically, cell cycle arrest induces diacylglycerol acyltransferase (DGAT)-dependent lipid droplet formation to sequester excessive polyunsaturated fatty acids (PUFAs) that accumulate in arrested cells in triacylglycerols (TAGs), resulting in ferroptosis suppression. Consequently, DGAT inhibition orchestrates a reshuffling of PUFAs from TAGs to phospholipids and re-sensitizes arrested cells to ferroptosis. We show that some slow-cycling antimitotic drug-resistant cancer cells, such as 5-fluorouracil-resistant cells, have accumulation of lipid droplets and that combined treatment with ferroptosis inducers and DGAT inhibitors effectively suppresses the growth of 5-fluorouracil-resistant tumors by inducing ferroptosis. Together, these results reveal a role for cell cycle arrest in driving ferroptosis resistance and suggest a ferroptosis-inducing therapeutic strategy to target slow-cycling therapy-resistant cancers.

Disulfidptosis: disulfide stress-induced cell death.

The cystine transporter solute carrier family 7 member 11 (SLC7A11) (also known as xCT) promotes glutathione synthesis and counters oxidative stress-induced cell death, including ferroptosis, by importing cystine. Also, SLC7A11 plays a crucial role in tumor development. However, recent studies have uncovered an unexpected role of SLC7A11 in promoting disulfidptosis, a novel form of regulated cell death induced by disulfide stress. In this review, we examine the opposing roles of SLC7A11 in regulating redox homeostasis and cell survival/death, summarize current knowledge on disulfidptosis, and explore its potential in disease treatment. A deeper understanding of disulfidptosis will offer new insights into fundamental cellular homeostasis and facilitate the development of innovative therapies for disease treatment.

Incorporation of protein induced by vitamin K absence or antagonist-II into transplant criteria expands beneficiaries of liver transplantation for hepatocellular carcinoma: a multicenter retrospective cohort study in China.

INTRODUCTION: In order to maximize the utilization of precious donor liver, precisely determining potential hepatocellular carcinoma (HCC) candidates who will benefit from liver transplantation (LT) is essential. As a crucial diagnostic biomarker for HCC, protein induced by vitamin K absence or antagonist-II (PIVKA-II) has become one of the key indicators for assessing tumor recurrence risk after LT. This study aims to investigate the role of PIVKA-II in recipient selection and prognostic stratification. METHODS: The clinicopathologic data of HCC patients undergoing LT from 2015 to 2020 in six Chinese transplant centers were collected. Univariate and multivariate analyses were performed to determine risk factors for disease free survival (DFS). Based on these risk factors, survival analysis was made by Kaplan-Meier method and their value in prognostic stratification was assessed. RESULTS: A total of 522 eligible HCC patients with pre-LT PIVKA-II records were finally included in this study. Tumor burden>8 cm, α-fetoprotein>400 ng/ml, histopathologic grade III and PIVKA-II>240 mAU/ml were identified as independent risk factors for DFS. DFS of patients with PIVKA-II≤240 mAU/ml ( N =288) were significantly higher than those with PIVKA-II>240 mAU/ml ( N =234) (1-year, 3-year, and 5-year DFS: 83.2, 77.3, and 75.9% vs. 75.1, 58.5, and 50.5%; P <0.001). Compared with Hangzhou criteria ( N =305), incorporating PIVKA-II into Hangzhou criteria (including tumor burden, α-fetoprotein, and histopathologic grade) increased the number of patients with eligibility for LT by 21.6% but achieved comparable DFS and overall survival. CONCLUSIONS: Incorporating PIVKA-II into existing LT criteria could increase the number of eligible HCC patients without compromising post-LT outcomes.

Immunotherapy and biomarkers in patients with lung cancer with tuberculosis: Recent advances and future Directions.

Lung cancer (LC) and tuberculosis (TB) are two major global public health problems, and the incidence of LC-TB is currently on the rise. Therefore effective clinical interventions are crucial for LC-TB. The aim of this review is to provide up-to-date information on the immunological profile and therapeutic biomarkers in patients with LC-TB. We discuss the immune mechanisms involved, including the immune checkpoints that play an important role in the treatment of patients with LC-TB. In addition, we explore the susceptibility of patients with LC to TB and summarise the latest research on LC-TB. Finally, we discuss future prospects in this field, including the identification of potential targets for immune intervention. In conclusion, this review provides important insights into the complex relationship between LC and TB and highlights new advances in the detection and treatment of both diseases.

Characterization of two novel Fe(III)-reducing and electrogenic bacteria, Shewanella ferrihydritica sp. nov. and Shewanella electrica sp. nov., isolated from mangrove sediment.

Three novel strains in the genus Shewanella, designated A3AT, C31T and C32, were isolated from mangrove sediment samples. They were facultative anaerobic, Gram-stain-negative, rod-shaped, flagellum-harbouring, oxidase- and catalase-positive, electrogenic and capable of using Fe(III) as an electron acceptor during anaerobic growth. Results of phylogenetic analysis based on 16S rRNA gene and genomic sequences revealed that the strains should be assigned to the genus Shewanella. The 16S rRNA gene similarity, average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between the isolates and their closely related species were below the respective cut-off values for species differentiation. The 16S rRNA gene similarity, ANI and dDDH values between strains C31T and C32 were 99.7, 99.9 and 99.9 %, respectively, indicating that they should belong to the same genospecies. Based on polyphasic taxonomic approach, two novel species are proposed, Shewanella ferrihydritica sp. nov. with type strain A3AT (GDMCC 1.2732T=JCM 34899T) and Shewanella electrica sp. nov. with type strain C31T (GDMCC 1.2736T=JCM 34902T).

AK112, a novel PD-1/VEGF bispecific antibody, in combination with chemotherapy in patients with advanced non-small cell lung cancer (NSCLC): an open-label, multicenter, phase II trial.

Background: Inhibiting vascular endothelial growth factor (VEGF) function can improve the efficacy of immunotherapy by modulating the tumor immune microenvironment. AK112 is the first-in-class humanized IgG1 bispecific antibody targeting programmed death-1 (PD-1) and VEGF. This study aimed to evaluate the efficacy and safety of AK112 combined with chemotherapy in patients with advanced non-small cell lung cancer (NSCLC). Methods: This open-label, multicenter, phase II clinical trial was conducted in 11 hospitals in China. Eligible participants were adults aged 18-75 years with locally advanced or metastatic NSCLC, an Eastern Cooperative Oncology Group performance status of 0 or 1, at least one measurable lesion, and an estimated life expectancy of at least 3 months. The participants were categorized into three cohorts based on prior therapy and functional genomic alterations. Patients in cohort 1 were previously untreated advanced NSCLC, had no epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) gene modifications, and received AK112 combined with pemetrexed (500 mg/m2) for non-squamous (non-sq)-NSCLC or paclitaxel (175 mg/m2) for sq-NSCLC plus carboplatin (area under the curve of 5 mg/mL per min) for four cycles, followed by AK112 with pemetrexed for non-sq-NSCLC and AK112 alone for sq-NSCLC as maintenance therapy. The participants in cohort 2 had advanced NSCLC with EGFR-sensitive mutations, failed previous EGFR-tyrosine kinase inhibitor (TKI) therapy, and received pemetrexed plus AK112 and carboplatin for four cycles, followed by pemetrexed plus AK112 as maintenance therapy. The participants in cohort 3 had advanced NSCLC who failed systemic platinum-based chemotherapy and anti-PD-1/programmed death-ligand 1 (PD-L1) treatments and received AK112 plus docetaxel (75 mg/m2). Two dosages of AK112 (10 or 20 mg/kg) were examined in each cohort, and the drug was administered intravenously on day 1 of each 3-week treatment cycle. The primary endpoints were the investigator-assessed objective response rate (ORR) and safety. This study was registered with ClinicalTrials.gov (NCT04736823). Findings: Eighty-three patients were enrolled from February 2021 to August 2022 and received the study treatment. Cohorts 1, 2, and 3 had 44, 19, and 20 patients, respectively. The confirmed ORR was 53.5% (23/43) [95% CI, 36.9-67.1], 68.4% (13/19) [95% CI, 43.4-87.4], and 40.0% (8/20) [95% CI, 19.1-63.9] in cohorts 1, 2, and 3, respectively. In cohort 1, the median PFS was not reached, and the 12-month PFS rate was 59.1%. In cohorts 2 and 3, the median PFS were 8.5 [95% CI, 5.5-NE] and 7.5 [95% CI, 2.3-NE] months, and the 12-month PFS rates were 35.5% and 44.5%, respectively. The most common grade ≥3 treatment-related adverse events were decreased white blood cell count [7 (8.4%)], neutropenia [5 (6.0%)], thrombocytopenia [2 (2.4%)], anemia [4 (4.8%)], and myelosuppression [2 (2.4%)]. Interpretation: AK112 plus platinum-doublet showed promising antitumor activity and safety not only in first-line treatment of advanced NSCLC patients without driver mutation but also in patients with EGFR-functional mutation who failed previous EGFR-TKI therapy and advanced NSCLC patients who failed prior systemic platinum-based chemotherapy and PD-1/PD-L1 inhibitor treatments, suggesting a valuable potential new treatment option for this patient population. Funding: Akeso Biopharma, Inc., Zhongshan, China, and National Natural Science Foundation of China.

Unleashing ferroptosis for cancer therapy with warfarin.

Ferroptosis holds promise for cancer therapy. A recent study by Yang et al. in Cell Metabolism reveals that VKORC1L1-mediated reduction of vitamin K inhibits ferroptosis and establishes a direct p53-VKORC1L1 link in its regulation. As warfarin can inhibit VKORC1L1, the study further underscores this drug's potential as a cancer therapy.

HNRNPA2B1-mediated m6A modification of lncRNA MEG3 facilitates tumorigenesis and metastasis of non-small cell lung cancer by regulating miR-21-5p/PTEN axis.

BACKGROUND: Accumulating data indicate that N6-methyladenosine (m6A) RNA methylation and lncRNA deregulation act crucial roles in cancer progression. Heterogeneous nuclear ribonucleoprotein A2B1 (HNRNPA2B1) as an m6A "reader" has been reported to be an oncogene in multiple malignancies. We herein aimed to elucidate the role and underlying mechanism by which HNRNPA2B1-mediated m6A modification of lncRNAs contributes to non-small cell lung cancer (NSCLC). METHODS: The expression levels of HNRNPA2B1 and their association with the clinicopathological characteristics and prognosis in NSCLC were determined by RT-qPCR, Western blot, immunohistochemistry and TCGA dataset. Then, the role of HNRNPA2B1 in NSCLC cells was assessed by in vitro functional experiments and in vivo tumorigenesis and lung metastasis models. HNRNPA2B1-mediated m6A modification of lncRNAs was screened by m6A-lncRNA epi-transcriptomic microarray and verified by methylated RNA immunoprecipitation (Me-RIP). The lncRNA MEG3-specific binding with miR-21-5p was evaluated by luciferase gene report and RIP assays. The effects of HNRNPA2B1 and (or) lncRNA MEG3 on miR-21-5p/PTEN/PI3K/AKT signaling were examined by RT-qPCR and Western blot analyses. RESULTS: We found that upregulation of HNRNPA2B1 was associated with distant metastasis and poor survival, representing an independent prognostic factor in patients with NSCLC. Knockdown of HNRNPA2B1 impaired cell proliferation and metastasis in vitro and in vivo, whereas ectopic expression of HNRNPA2B1 possessed the opposite effects. Mechanical investigations revealed that lncRNA MEG3 was an m6A target of HNRNPA2B1 and inhibition of HNRNPA2B1 decreased MEG3 m6A levels but increased its mRNA levels. Furthermore, lncRNA MEG3 could act as a sponge of miR-21-5p to upregulate PTEN and inactivate PI3K/AKT signaling, leading to the suppression of cell proliferation and invasion. Low expression of lncRNA MEG3 or elevated expression of miR-21-5p indicated poor survival in patients with NSCLC. CONCLUSIONS: Our findings uncover that HNRNPA2B1-mediated m6A modification of lncRNA MEG3 promotes tumorigenesis and metastasis of NSCLC cells by regulating miR-21-5p/PTEN axis and may provide a therapeutic target for NSCLC.

Malignancy in dermatomyositis: a mono-centric retrospective study of 134 patients in China and a potential predictive model.

Objectives: To describe the demographics and phenotypes of malignancies-associated dermatomyositis (MADM) in east China and pinpoint potential factors indicative of malignancies in patients with dermatomyositis and establish a predictive model. Methods: We retrospectively analyzed clinical data from 134 patients with adult-onset dermatomyositis hospitalized between January 2019 and May 2022 in one comprehensive hospital. Clinical data including disease course, initial symptoms and signs, and demographic information were retrieved from the Electronic Medical Records System. Other parameters including myositis-specific autoantibodies profiles, ferritin, sedimentation, etc. were all referable. Multivariable multinomial logistic regression was employed to simulate a model to predict cancer risks. Receiver operating characteristic curve was adopted to evaluate the potency of the model. Results: 134 patients with adult-onset dermatomyositis were aptly enrolled in this study based on inclusive and exclusive criteria: 12 (8.96%) with malignancies, 57 (42.53%) with aberrant tumor biomarkers but no malignancies, 65 (48.51%) with neither malignancies nor abnormal tumor biomarkers. Senior diagnostic age, higher LDH, higher ferritin, positive anti-TIF1γ and anti-Mi2 rather than anti-NXP2 autoantibodies were positive indicators of malignancies. Additionally, neither initial complaints nor signs were found to be correlated to a tendency towards malignancies. Digestive system, nasopharyngeal, and lung malignancies were mostly documented in east China. One multivariable multinomial logistic regression model was established to predict the phenotypes of dermatomyositis on the basis of potential malignancies and the overall sensitivity and specificity was satisfactory. Conclusion: Positivity of anti-TIF1γ and anti-Mi2 autoantibodies are highly indicative of malignancies while the role of anti-NXP2 autoantibody in MADM in the Chinese population remains unclear. The phenotypes of malignancies can be predicted through the model and the predictive power is sufficient. More attention should be paid to malignancies screening in patients with aberrant tumor biomarkers but no malignancies, particularly digestive system, nasopharyngeal, and lung malignancies in patients with dermatomyositis but without malignancies.

SLC7A11 expression level dictates differential responses to oxidative stress in cancer cells.

The cystine transporter solute carrier family 7 member 11 (SLC7A11; also called xCT) protects cancer cells from oxidative stress and is overexpressed in many cancers. Here we report a surprising finding that, whereas moderate overexpression of SLC7A11 is beneficial for cancer cells treated with H2O2, a common oxidative stress inducer, its high overexpression dramatically increases H2O2-induced cell death. Mechanistically, high cystine uptake in cancer cells with high overexpression of SLC7A11 in combination with H2O2 treatment results in toxic buildup of intracellular cystine and other disulfide molecules, NADPH depletion, redox system collapse, and rapid cell death (likely disulfidptosis). We further show that high overexpression of SLC7A11 promotes tumor growth but suppresses tumor metastasis, likely because metastasizing cancer cells with high expression of SLC7A11 are particularly susceptible to oxidative stress. Our findings reveal that SLC7A11 expression level dictates cancer cells' sensitivity to oxidative stress and suggests a context-dependent role for SLC7A11 in tumor biology.

Ferroptosis vulnerability in FLT3-mutant leukemia.

Resistance to FLT3 inhibition is a prevalent challenge in managing FLT3-mutant acute myeloid leukemia (AML). A recent study by Sabatier et al. discovered ferroptosis vulnerability in FLT3-mutant AML and they propose a promising therapeutic approach of combining FLT3 inhibitors with ferroptosis inducers for treating this type of cancer.