Glutamine suppresses senescence and promotes autophagy through glycolysis inhibition-mediated AMPKα lactylation in intervertebral disc degeneration.

Regulating metabolic disorders has become a promising focus in treating intervertebral disc degeneration (IDD). A few drugs regulating metabolism, such as atorvastatin, metformin, and melatonin, show positive effects in treating IDD. Glutamine participates in multiple metabolic processes, including glutaminolysis and glycolysis; however, its impact on IDD is unclear. The current study reveals that glutamine levels are decreased in severely degenerated human nucleus pulposus (NP) tissues and aging Sprague-Dawley (SD) rat nucleus pulposus tissues, while lactate accumulation and lactylation are increased. Supplementary glutamine suppresses glycolysis and reduces lactate production, which downregulates adenosine-5'-monophosphate-activated protein kinase α (AMPKα) lactylation and upregulates AMPKα phosphorylation. Moreover, glutamine treatment reduces NP cell senescence and enhances autophagy and matrix synthesis via inhibition of glycolysis and AMPK lactylation, and glycolysis inhibition suppresses lactylation. Our results indicate that glutamine could prevent IDD by glycolysis inhibition-decreased AMPKα lactylation, which promotes autophagy and suppresses NP cell senescence.

Nano-medicine therapy reprogramming metabolic network of tumour microenvironment: new opportunity for cancer therapies.

Metabolic heterogeneity is one of the characteristics of tumour cells. In order to adapt to the tumour microenvironment of hypoxia, acidity and nutritional deficiency, tumour cells have undergone extensive metabolic reprogramming. Metabolites involved in tumour cell metabolism are also very different from normal cells, such as a large number of lactate and adenosine. Metabolites play an important role in regulating the whole tumour microenvironment. Taking metabolites as the target, it aims to change the metabolic pattern of tumour cells again, destroy the energy balance it maintains, activate the immune system, and finally kill tumour cells. In this paper, the regulatory effects of metabolites such as lactate, glutamine, arginine, tryptophan, fatty acids and adenosine were reviewed, and the related targeting strategies of nano-medicines were summarised, and the future therapeutic strategies of nano-drugs were discussed. The abnormality of tumour metabolites caused by tumour metabolic remodelling not only changes the energy and material supply of tumour, but also participates in the regulation of tumour-related signal pathways, which plays an important role in the survival, proliferation, invasion and metastasis of tumour cells. Regulating the availability of local metabolites is a new aspect that affects tumour progress. (The graphical abstract is by Figdraw).

Metabolic heterogeneity is one of the important characteristics of tumour cells, and the metabolites of tumour cells are very different from those of normal cells.Lactate, fatty acids, glutamine, arginine, tryptophan and adenosine are all important metabolites in tumour metabolism.Nano-medicines are used to regulate tumour metabolites, affecting the energy and material supply of tumour cells, thus achieving therapeutic effects.

The radiation- and chemo-sensitizing capacity of diclofenac can be predicted by a decreased lactate metabolism and stress response.

BACKGROUND: An enhanced aerobic glycolysis ("Warburg effect") associated with an increase in lactic acid in the tumor microenvironment contributes to tumor aggressiveness and resistance to radiation and chemotherapy. We investigated the radiation- and chemo-sensitizing effects of the nonsteroidal anti-inflammatory drug (NSAID) diclofenac in different cancer cell types. METHODS: The effects of a non-lethal concentration of diclofenac was investigated on c-MYC and Lactate Dehydrogenase (LDH) protein expression/activity and the Heat shock Protein (HSP)/stress response in human colorectal (LS174T, LoVo), lung (A549), breast (MDA-MB-231) and pancreatic (COLO357) carcinoma cells. Radiation- and chemo-sensitization of diclofenac was determined using clonogenic cell survival assays and a murine xenograft tumor model. RESULTS: A non-lethal concentration of diclofenac decreases c-MYC protein expression and LDH activity, reduces cytosolic Heat Shock Factor 1 (HSF1), Hsp70 and Hsp27 levels and membrane Hsp70 positivity in LS174T and LoVo colorectal cancer cells, but not in A549 lung carcinoma cells, MDA-MB-231 breast cancer cells and COLO357 pancreatic adenocarcinoma cells. The impaired lactate metabolism and stress response in diclofenac-sensitive colorectal cancer cells was associated with a significantly increased sensitivity to radiation and 5Fluorouracil in vitro, and in a human colorectal cancer xenograft mouse model diclofenac causes radiosensitization. CONCLUSION: These findings suggest that a decrease in the LDH activity and/or stress response upon diclofenac treatment predicts its radiation/chemo-sensitizing capacity.

Current Advances on Nanomaterials Interfering with Lactate Metabolism for Tumor Therapy.

Increasing numbers of studies have shown that tumor cells prefer fermentative glycolysis over oxidative phosphorylation to provide a vast amount of energy for fast proliferation even under oxygen-sufficient conditions. This metabolic alteration not only favors tumor cell progression and metastasis but also increases lactate accumulation in solid tumors. In addition to serving as a byproduct of glycolytic tumor cells, lactate also plays a central role in the construction of acidic and immunosuppressive tumor microenvironment, resulting in therapeutic tolerance. Recently, targeted drug delivery and inherent therapeutic properties of nanomaterials have attracted great attention, and research on modulating lactate metabolism based on nanomaterials to enhance antitumor therapy has exploded. In this review, the advanced tumor therapy strategies based on nanomaterials that interfere with lactate metabolism are discussed, including inhibiting lactate anabolism, promoting lactate catabolism, and disrupting the "lactate shuttle". Furthermore, recent advances in combining lactate metabolism modulation with other therapies, including chemotherapy, immunotherapy, photothermal therapy, and reactive oxygen species-related therapies, etc., which have achieved cooperatively enhanced therapeutic outcomes, are summarized. Finally, foreseeable challenges and prospective developments are also reviewed for the future development of this field.

NIR-Activatable Heterostructured Nanoadjuvant CoP/NiCoP Executing Lactate Metabolism Interventions for Boosted Photocatalytic Hydrogen Therapy and Photoimmunotherapy.

Near-infrared (NIR) laser-induced photoimmunotherapy has aroused great interest due to its intrinsic noninvasiveness and spatiotemporal precision, while immune evasion evoked by lactic acid (LA) accumulation severely limits its clinical outcomes. Although several metabolic interventions have been devoted to ameliorate immunosuppression, intracellular residual LA still remains a potential energy source for oncocyte proliferation. Herein, an immunomodulatory nanoadjuvant based on a yolk-shell CoP/NiCoP (CNCP) heterostructure loaded with the monocarboxylate transporter 4 inhibitor fluvastatin sodium (Flu) is constructed to concurrently relieve immunosuppression and elicit robust antitumor immunity. Under NIR irradiation, CNCP heterojunctions exhibit superior photothermal performance and photocatalytic production of reactive oxygen species and hydrogen. The continuous heat then facilitates Flu release to restrain LA exudation from tumor cells, whereas cumulative LA can be depleted as a hole scavenger to improve photocatalytic efficiency. Subsequently, potentiated photocatalytic therapy can not only initiate systematic immunoreaction, but also provoke severe mitochondrial dysfunction and disrupt the energy supply for heat shock protein synthesis, in turn realizing mild photothermal therapy. Consequently, LA metabolic remodeling endows an intensive cascade treatment with an optimal safety profile to effectually suppress tumor proliferation and metastasis, which offers a new paradigm for the development of metabolism-regulated immunotherapy.

Role of monocarboxylate transporter I/lactate dehydrogenase B-mediated lactate recycling in tamoxifen-resistant breast cancer cells.

Although tamoxifen (TAM) is widely used in patients with estrogen receptor-positive breast cancer, the development of tamoxifen resistance is common. The previous finding suggests that the development of tamoxifen resistance is driven by epiregulin or hypoxia-inducible factor-1α-dependent glycolysis activation. Nonetheless, the mechanisms responsible for cancer cell survival and growth in a lactic acid-rich environment remain elusive. We found that the growth and survival of tamoxifen-resistant MCF-7 cells (TAMR-MCF-7) depend on glycolysis rather than oxidative phosphorylation. The levels of the glycolytic enzymes were higher in TAMR-MCF-7 cells than in parental MCF-7 cells, whereas the mitochondrial number and complex I level were decreased. Importantly, TAMR-MCF-7 cells were more resistant to low glucose and high lactate growth conditions. Isotope tracing analysis using 13C-lactate confirmed that lactate conversion to pyruvate was enhanced in TAMR-MCF-7 cells. We identified monocarboxylate transporter1 (MCT1) and lactate dehydrogenase B (LDHB) as important mediators of lactate influx and its conversion to pyruvate, respectively. Consistently, AR-C155858 (MCT1 inhibitor) inhibited the proliferation, migration, spheroid formation, and in vivo tumor growth of TAMR-MCF-7 cells. Our findings suggest that TAMR-MCF-7 cells depend on glycolysis and glutaminolysis for energy and support that targeting MCT1- and LDHB-dependent lactate recycling may be a promising strategy to treat patients with TAM-resistant breast cancer.

NFYB increases chemosensitivity in glioblastoma by promoting HDAC5-mediated transcriptional inhibition of SHMT2.

Temozolomide (TMZ) is a commonly used chemotherapeutic agent for glioblastoma (GBM), but acquired drug resistance prevents its therapeutic efficacy. We investigated potential mechanisms underlying TMZ resistance and glycolysis in GBM cells through regulation by nuclear transcription factor Y subunit ß (NFYB) of the oncogene serine hydroxymethyltransferase 2 (SHMT2). GBM U251 cells were transfected with NFYB-, SHMT2-, and the potential NFYB target histone deacetylase 5 (HDAC5)-related vectors. Glucose uptake and lactate production were measured with detection kits. CCK-8/colony formation, scratch, Transwell, and flow cytometry assays were performed to detect cell proliferation, migration, invasion, and apoptosis, respectively. The binding of NFYB to the HDAC5 promoter and the regulation of NFYB on HDAC5 promoter activity were detected with chromatin immunoprecipitation and dual-luciferase reporter assays, respectively. NFYB and HDAC5 were poorly expressed and SHMT2 was expressed at high levels in GBM U251 cells. NFYB overexpression or SHMT2 knockdown decreased glucose uptake, lactate production, proliferation, migration, and invasion and increased apoptosis and TMZ sensitivity of the cells. NFYB activated HDAC5 to inhibit SHMT2 expression. SHMT2 overexpression nullified the inhibitory effects of NFYB overexpression on glycolysis and TMZ resistance. Thus, NFYB may reduce tumorigenicity and TMZ resistance of GBM through effects on the HDAC5/SHMT2 axis.

STAT5 promotes PD-L1 expression by facilitating histone lactylation to drive immunosuppression in acute myeloid leukemia.

Immunotherapy is a revolutionized therapeutic strategy for tumor treatment attributing to the rapid development of genomics and immunology, and immune checkpoint inhibitors have successfully achieved responses in numbers of tumor types, including hematopoietic malignancy. However, acute myeloid leukemia (AML) is a heterogeneous disease and there is still a lack of systematic demonstration to apply immunotherapy in AML based on PD-1/PD-L1 blockage. Thus, the identification of molecules that drive tumor immunosuppression and stratify patients according to the benefit from immune checkpoint inhibitors is urgently needed. Here, we reported that STAT5 was highly expressed in the AML cohort and activated the promoter of glycolytic genes to promote glycolysis in AML cells. As a result, the increased-lactate accumulation promoted E3BP nuclear translocation and facilitated histone lactylation, ultimately inducing PD-L1 transcription. Immune checkpoint inhibitor could block the interaction of PD-1/PD-L1 and reactive CD8+ T cells in the microenvironment when co-culture with STAT5 constitutively activated AML cells. Clinically, lactate accumulation in bone marrow was positively correlated with STAT5 as well as PD-L1 expression in newly diagnosed AML patients. Therefore, we have illustrated a STAT5-lactate-PD-L1 network in AML progression, which demonstrates that AML patients with STAT5 induced-exuberant glycolysis and lactate accumulation may be benefited from PD-1/PD-L-1-based immunotherapy.

Continuous renal replacement therapy with the adsorptive oXiris filter may be associated with the lower 28-day mortality in sepsis: a systematic review and meta-analysis.

BACKGROUND: The oXiris is a novel filter for continuous renal replacement therapy (CRRT) featuring an adsorption coating to adsorb endotoxins and remove inflammatory mediators. Given that no consensus has been reached on its potential benefits in treating sepsis, a meta-analysis was conducted to assess its impact on the clinical outcomes of this patient population. METHODS: Eleven databases were retrieved to find relevant observational studies and randomized controlled trials. The Newcastle-Ottawa Scale and the Cochrane Risk of Bias Tool were used to assess the quality of the included studies. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) process was employed to assess the certainty of evidence. The 28-day mortality was the primary outcome. Secondary outcomes were 7-, 14-, and 90-day mortality, length of intensive care unit (ICU) and hospital stay, ICU and hospital mortality, norepinephrine (NE) dose, interleukin-6 (IL-6) and lactate levels, and Sequential Organ Failure Assessment (SOFA) score. RESULTS: The meta-analysis, pooling data from 14 studies, involving 695 patients, showed significant reductions in 28-day mortality [odds ratio (OR) 0.53; 95% confidence interval (CI) 0.36-0.77, p = 0.001] and length of ICU stay [weighted mean difference (WMD) - 1.91; 95% CI - 2.56 to - 1.26, p < 0.001)] in patients with sepsis using the oXiris filter compared to other filters. Besides, the SOFA score, NE dose, IL-6 and lactate levels, and 7- and 14-day mortalities were lower in the oXiris group. However, the 90-day mortality, ICU and hospital mortality, and length of hospital stay were comparable. The quality assessment of the ten observational studies indicated intermediate to high quality (average Newcastle-Ottawa score: 7.8). However, all four randomized controlled trials (RCTs) had an unclear risk of bias. The evidence for all outcomes had a low or very low level of certainty because the original study design was mainly observational studies and the RCTs included had an unclear risk of bias and a small sample size. CONCLUSION: The treatment with the oXiris filter during CRRT in sepsis patients may be associated with lower 28-, 7-, and 14-day mortalities, lactate levels, SOFA score, NE dose, and shorter length of ICU stay. However, due to the low or very low quality of evidence, the effectiveness of oXiris filters was still uncertain. Besides, no significant difference was observed for the 90-day mortality, ICU and hospital mortality, and length of hospital stay.

Histone Methyltransferase NSD2 Activates PKCα to Drive Metabolic Reprogramming and Lenalidomide Resistance in Multiple Myeloma.

Multiple myeloma cells undergo metabolic reprogramming in response to the hypoxic and nutrient-deprived bone marrow microenvironment. Primary oncogenes in recurrent translocations might be able to drive metabolic heterogeneity to survive the microenvironment that can present new vulnerabilities for therapeutic targeting. t(4;14) translocation leads to the universal overexpression of histone methyltransferase NSD2 that promotes plasma cell transformation through a global increase in H3K36me2. Here, we identified PKCα as an epigenetic target that contributes to the oncogenic potential of NSD2. RNA sequencing of t(4;14) multiple myeloma cell lines revealed a significant enrichment in the regulation of metabolic processes by PKCα, and the glycolytic gene, hexokinase 2 (HK2), was transcriptionally regulated by PKCα in a PI3K/Akt-dependent manner. Loss of PKCα displaced mitochondria-bound HK2 and reversed sensitivity to the glycolytic inhibitor 3-bromopyruvate. In addition, the perturbation of glycolytic flux led to a metabolic shift to a less energetic state and decreased ATP production. Metabolomics analysis indicated lactate as a differential metabolite associated with PKCα. As a result, PKCα conferred resistance to the immunomodulatory drugs (IMiD) lenalidomide in a cereblon-independent manner and could be phenocopied by either overexpression of HK2 or direct supplementation of lactate. Clinically, t(4;14) patients had elevated plasma lactate levels and did not benefit from lenalidomide-based regimens. Altogether, this study provides insights into the epigenetic-metabolism cross-talk in multiple myeloma and highlights the opportunity for therapeutic intervention that leverages the distinct metabolic program in t(4;14) myeloma. SIGNIFICANCE: Aberrant glycolysis driven by NSD2-mediated upregulation of PKCα can be therapeutically exploited using metabolic inhibitors with lactate as a biomarker to identify high-risk patients who exhibit poor response towards IMiD-based regimens.

MCT4-dependent lactate secretion suppresses antitumor immunity in LKB1-deficient lung adenocarcinoma.

Inactivating STK11/LKB1 mutations are genomic drivers of primary resistance to immunotherapy in KRAS-mutated lung adenocarcinoma (LUAD), although the underlying mechanisms remain unelucidated. We find that LKB1 loss results in enhanced lactate production and secretion via the MCT4 transporter. Single-cell RNA profiling of murine models indicates that LKB1-deficient tumors have increased M2 macrophage polarization and hypofunctional T cells, effects that could be recapitulated by the addition of exogenous lactate and abrogated by MCT4 knockdown or therapeutic blockade of the lactate receptor GPR81 expressed on immune cells. Furthermore, MCT4 knockout reverses the resistance to PD-1 blockade induced by LKB1 loss in syngeneic murine models. Finally, tumors from STK11/LKB1 mutant LUAD patients demonstrate a similar phenotype of enhanced M2-macrophages polarization and hypofunctional T cells. These data provide evidence that lactate suppresses antitumor immunity and therapeutic targeting of this pathway is a promising strategy to reversing immunotherapy resistance in STK11/LKB1 mutant LUAD.

Combination Therapy With CD147-Targeted Nanoparticles Carrying Phenformin Decreases Lung Cancer Growth.

Lung cancer is one of the most fatal cancers worldwide. Resistance to conventional therapies remains a hindrance to patient treatment. Therefore, the development of more effective anti-cancer therapeutic strategies is imperative. Solid tumors exhibit a hyperglycolytic phenotype, leading to enhanced lactate production; and, consequently, its extrusion to the tumor microenvironment. Previous data reveals that inhibition of CD147, the chaperone of lactate transporters (MCTs), decreases lactate export in lung cancer cells and sensitizes them to phenformin, leading to a drastic decrease in cell growth. In this study, the development of anti-CD147 targeted liposomes (LUVs) carrying phenformin is envisioned, and their efficacy is evaluated to eliminate lung cancer cells. Herein, the therapeutic effect of free phenformin and anti-CD147 antibody, as well as the efficacy of anti-CD147 LUVs carrying phenformin on A549, H292, and PC-9 cell growth, metabolism, and invasion, are evaluated. Data reveals that phenformin decreases 2D and 3D-cancer cell growth and that the anti-CD147 antibody reduces cell invasion. Importantly, anti-CD147 LUVs carrying phenformin are internalized by cancer cells and impaired lung cancer cell growth in vitro and in vivo. Overall, these results provide evidence for the effectiveness of anti-CD147 LUVs carrying phenformin in compromising lung cancer cell aggressiveness.

Is pre-radiotherapy metabolic heterogeneity of glioblastoma predictive of progression-free survival?

BACKGROUND AND PURPOSE: All glioblastoma subtypes share the hallmark of aggressive invasion, meaning that it is crucial to identify their different components if we are to ensure effective treatment and improve survival. Proton MR spectroscopic imaging (MRSI) is a noninvasive technique that yields metabolic information and is able to identify pathological tissue with high accuracy. The aim of the present study was to identify clusters of metabolic heterogeneity, using a large MRSI dataset, and determine which of these clusters are predictive of progression-free survival (PFS). MATERIALS AND METHODS: MRSI data of 180 patients acquired in a pre-radiotherapy examination were included in the prospective SPECTRO-GLIO trial. Eight features were extracted for each spectrum: Cho/NAA, NAA/Cr, Cho/Cr, Lac/NAA, and the ratio of each metabolite to the sum of all the metabolites. Clustering of data was performed using a mini-batch k-means algorithm. The Cox model and logrank test were used for PFS analysis. RESULTS: Five clusters were identified as sharing similar metabolic information and being predictive of PFS. Two clusters revealed metabolic abnormalities. PFS was lower when Cluster 2 was the dominant cluster in patients' MRSI data. Among the metabolites, lactate (present in this cluster and in Cluster 5) was the most statistically significant predictor of poor outcome. CONCLUSION: Results showed that pre-radiotherapy MRSI can be used to reveal tumor heterogeneity. Groups of spectra, which have the same metabolic information, reflect the different tissue components representative of tumor burden proliferation and hypoxia. Clusters with metabolic abnormalities and high lactate are predictive of PFS.

Evaluation of levosimendan as treatment option in a large case-series of preterm infants with cardiac dysfunction and pulmonary hypertension.

Levosimendan as a calcium-sensitizer is a promising innovative therapeutical option for the treatment of severe cardiac dysfunction (CD) and pulmonary hypertension (PH) in preterm infants, but no data are available analyzing levosimendan in cohorts of preterm infants. The design/setting of the evaluation is in a large case-series of preterm infants with CD and PH. Data of all preterm infants (gestational age (GA) < 37 weeks) with levosimendan treatment and CD and/or PH in the echocardiographic assessment between 01/2018 and 06/2021 were screened for analysis. The primary clinical endpoint was defined as echocardiographic response to levosimendan. Preterm infants (105) were finally enrolled for further analysis. The preterm infants (48%) were classified as extremely low GA newborns (ELGANs, < 28 weeks of GA) and 73% as very low birth weight infants (< 1500 g, VLBW). The primary endpoint was reached in 71%, without difference regarding GA or BW. The incidence of moderate or severe PH decreased from baseline to follow-up (24 h) in about 30%, with a significant decrease in the responder group (p < 0.001). The incidence of left ventricular dysfunction and bi-ventricular dysfunction decreased significantly from baseline to follow-up (24 h) in the responder-group (p = 0.007, and p < 0.001, respectively). The arterial lactate level decreased significantly from baseline (4.7 mmol/l) to 12 h (3.6 mmol/l, p < 0.05), and 24 h (3.1 mmol/l, p < 0.01).  Conclusion: Levosimendan treatment is associated with an improvement of both CD and PH in preterm infants, with a stabilization of the mean arterial pressure during the treatment and a significant decrease of arterial lactate levels. Future prospective trials are highly warranted. What is Known: • Levosimendan as a calcium-sensitizer and inodilator is known to improve the low cardiac output syndrome (LCOS), and improves ventricular dysfunction, and PH, both in pediatric as well as in adult populations. Data related to critically ill neonates without major cardiac surgery and preterm infants are not available. What is New: • This study evaluated the effect of levosimendan on hemodynamics, clinical scores, echocardiographic severity parameters, and arterial lactate levels in a case-series of 105 preterm infants for the first time. Levosimendan treatment in preterm infants is associated with a rapid improvement of CD and PH, an increase of the mean arterial pressure, and a significant decrease in arterial lactate levels, as surrogate marker for a LCOS. • How this study might affect research, practice, or policy. As no data are available regarding the use of levosimendan in this population, our results hopefully animate the research community to conduct future prospective trails analyzing levosimendan in randomized controlled trials (RCT) and observational control studies. Additionally, our results potentially motivate clinicians to introduce levosimendan as second second-line therapy in cases of severe CD and PH in preterm infants without improvement using standard treatment strategies.

A randomised-controlled trial (TARGET-C) of high vs. low target mean arterial pressure in patients with cirrhosis and septic shock.

BACKGROUND & AIMS: A high mean arterial pressure (MAP) target has been associated with improved renal outcomes in patients with cirrhosis, though it has not been studied in critically ill patients with cirrhosis and septic shock (CICs). We compared the efficacy of a high (80-85 mmHg; H-MAP) vs. low (60-65; L-MAP) target MAP strategy in improving 28-day mortality in CICs. METHODS: We performed open-label 1:1 randomisation of 150 CICs (H-MAP 75; L-MAP 75). The primary endpoint was 28-day mortality and secondary endpoints included reversal of shock, acute kidney injury (AKI) at day 5, the incidence of intradialytic hypotension (IDH), and adverse events. Endothelial markers were analysed in a subset of patients. RESULTS: The baseline characteristics were comparable. On intention-to-treat analysis, 28-day mortality (65% vs. 56%; p = 0.54), reversal of shock (47% vs. 53%; p = 0.41) and AKI development (45% vs. 31%;p = 0.06) were not different between the H-MAP and L-MAP groups, respectively. A lower incidence of IDH (12% vs. 48%; p <0.001) and higher adverse events necessitating protocol discontinuation (24% vs. 11%; p = 0.031) were noted in the H-MAP group. On per-protocol analysis (L-MAP 67; H-MAP 57), a significantly higher reversal of AKI (53% vs. 31%; p = 0.02) and a lower incidence of IDH (4% vs. 53%; p <0.001) were observed in the H-MAP group. Endothelial repair markers such as ADAMTS (2.11 ± 1.13 vs. 1.15 ± 0.48; p = 0.002) and angiopoietin-2 (74.08 ± 53.00 vs. 41.80 ± 15.95; p = 0.016) were higher in the H-MAP group. CONCLUSIONS: A higher MAP strategy does not confer a survival benefit in CICs, but improves tolerance to dialysis, lactate clearance and renal recovery. Higher adverse events indicate the need for better tools to evaluate target microcirculation pressures in CICs. IMPACT AND IMPLICATIONS: Maintaining an appropriate organ perfusion pressure during sepsis is the ultimate goal of haemodynamic management. A higher mean arterial pressure (MAP) improves renal outcomes in patients with hepatorenal syndrome. Patients with cirrhosis and septic shock have severe circulatory disturbances, low MAP, and poor tissue perfusion. In these patients, targeting higher MAP vs. lower MAP does not confer any survival benefit but is associated with more adverse events. A higher target strategy was associated with better tolerance and lesser episodes of hypotension on dialysis. Patients who could achieve the higher target MAP, without the development of adverse events, had improved renal outcomes and better lactate clearance. Higher MAP was also associated with improvements in markers of endothelial function. A higher target MAP strategy, with close monitoring of adverse events, may be recommended for patients with cirrhosis and septic shock. CLINICAL TRIAL NUMBER: NCT03145168.

An enzyme-instructed self-assembly system induces tumor acidosis via sequential-dual effect for cancer selective therapy.

The acidosis anti-tumor therapy, based on the altered energy metabolism pathway of tumor cells, has been proposed as an attractive method for cancer selective treatment. However, the strategy of inducing tumor acidosis by using a single drug to simultaneously inhibit both lactate efflux and consumption has not been reported yet. Herein, an in situ enzyme-instructed self-assembly (EISA) system was rationally fabricated to induce tumor acidosis apoptosis for cancer selective therapy. Depending on the sequential effect of the in situ EISA system, the targeted drug was successively distributed on the membrane and intracellular, inhibiting MCT4 mediated lactate efflux and mitochondrial tricarboxylic acid (TCA) cycle mediated lactate consumption, respectively. Through the dual obstruction of lactate metabolism to trigger tumor acidosis, the in situ EISA nanomedicine showed selective growth and migration inhibition against cancer cells. In addition, the nanomedicine also displayed a radio-sensitization effect in vitro due to causing the mitochondrial dysfunction, and exhibited a prominent synergistic chemo-radiotherapy anti-tumor performance in vivo. Accordingly, this work demonstrated that the in situ EISA system could endow the LND with sequential-dual effects to induce tumor acidosis, which may provide an enlightening strategy for anticancer drug delivery and cancer selective therapy. STATEMENT OF SIGNIFICANCE: With the help of the sequential effect of in situ EISA , the serial attack of LND against different targets was effectively realized to induce tumor acidosis and combined chemo-radiotherapy, implying the importance of the relationship between structure and function, which could offer a distinctive inspiration for future drug delivery system design and anti-tumor application.

Tumor cell density dependent IL-8 secretion induces the fluctuation of tregs/CD8 + T cells infiltration in hepatocellular carcinoma: one prompt for the existence of density checkpoint.

BACKGROUND: Tumor cell density is a basic pathological feature of solid tumors. Chemotherapy, radiotherapy, and targeted therapy reduce tumor cell density, whereas unrestricted tumor cell proliferation promotes this feature. The impact of tumor cells on the microenvironment following changes in tumor cell density is still unclear. In this study, we focused on the response of key immune cell subsets to tumor cell density in hepatocellular carcinoma (HCC). METHODS: We determined the density of tumor and immune cells in the same area by section staining. We then identified potential mediators using polymerase chain reaction (PCR), enzyme-linked immunofluorescence assay (ELISA), 3D and co-culture, flow cytometry, and lentivirus intervention. The mechanism of lactate promotion was verified using lactate tests, bioinformatics, western blotting, and the above methods. The IL-8/DAPK1/lactate/regulatory T cell (Treg) axis was verified using a mouse liver cancer model. Tumor mutation burden was calculated using maftools in R. RESULTS: We found that the Treg/CD8 + T cell ratio is not consistent with tumor cell density in HCC, and a decreased Treg/CD8 + T cell ratio in the range of 5000-6000 cells/mm2 may elicit the possibility for immunotherapy in an immunosuppressive microenvironment. We showed that IL-8 mediates this immune fluctuation and promotes the infiltration of Tregs through the DAPK1/pyruvate kinase activity/lactate axis in HCC. Based on tumor ploidy and mutation burden data, we discussed the potential significance of immune fluctuation in the homeostasis of HCC mutation burden and proposed a "density checkpoint" and "entropy model" to describe this phenomenon. CONCLUSIONS: In summary, we report the mode of infiltration of Tregs/CD8 + T cells in response to tumor cell density and provide a new theoretical basis for IL-8 as a therapeutic target and the selection of an immunotherapy window in HCC.

Targeting the Glycolytic Enzyme PGK1 to Inhibit the Warburg Effect: A New Strategy for Keloid Therapy.

BACKGROUND: Aerobic glycolysis (the Warburg effect) may play an important role in keloid pathogenesis, which may be aggravated by the hypoxic microenvironment in keloids. Phosphoglycerate kinase 1 (PGK1), a key glycolytic enzyme, is essential for cellular aerobic glycolysis, but its role in keloid formation remains unknown. This study aimed to detect PGK1 expression in keloid tissue and investigate the effects of inhibiting PGK1 expression on keloid fibroblasts (KFbs) under hypoxia and normoxia. METHODS: Normal skin and keloid samples were separated into two parts, one was used for immunohistochemistry, and one for primary cell culture. PGK1 tissue expression was detected by immunohistochemistry. Reverse-transcriptase polymerase chain reaction and Western blotting were used to detect PGK1, GLUT1, LDHA, and COL1 expression, and glucose uptake and lactate production were detected with a microplate reader. Cell proliferation and apoptosis were investigated with IncuCyte and flow cytometry. Cell migration and invasion were detected with Transwell assays. Glycolytic function was explored with the Seahorse XF96 system. RESULTS: Immunohistochemistry showed PGK1 overexpression in keloid tissue compared with normal skin tissue ( P < 0.05). Consistently, PGK1 expression was significantly higher in KFbs than in normal skin fibroblasts (NFbs), and hypoxia stimulated PGK1 expression in KFbs and NFbs ( P < 0.05). PGK1 knockdown significantly inhibited KFb glycolysis, proliferation, migration, invasion, glucose consumption, and lactate production ( P < 0.05). Furthermore, GLUT1, LDHA, and COL1 expression was decreased in KFbs compared with NFbs ( P < 0.05). In addition, suppressing PGK1 may mediate the PI3K/AKT pathway to down-regulate GLUT1, LDHA, and COL1 expression ( P < 0.05). CONCLUSIONS: These findings provide new evidence that suppressing PGK1, inhibiting glycolysis, reduces KFb proliferation, migration, invasion, and type I collagen expression. Targeting PGK1 to inhibit the Warburg effect may be a new therapeutic strategy for keloids. CLINICAL RELEVANCE STATEMENT: This article may provide new suggestions into the pathogenesis and treatment of keloids. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.

Lactate-Oxidase-Instructed Cancer Diagnosis and Therapy.

Lactate oxidase (LOx) has attracted extensive interest in cancer diagnosis and therapy in recent years owing to its specific catalysis on l-lactate; its catalytic process consumes oxygen (O2 ) and generates a large amount of hydrogen peroxide (H2 O2 ) and pyruvate. Given high levels of lactate in tumor tissues and its tight correlation with tumor growth, metastasis, and recurrence, LOx-based biosensors including H2 O2 -based, O2 -based, pH-sensitive, and electrochemical have been designed for cancer diagnosis, and various LOx-based cancer therapy strategies including lactate-depletion-based metabolic cancer therapy/immunotherapy, hypoxia-activated chemotherapy, H2 O2 -based chemodynamic therapy, and multimodal synergistic cancer therapy have also been developed. In this review, the lactate-specific catalytic properties of LOx are introduced, and the recent advances on LOx-instructed cancer diagnostic or therapeutic platforms and corresponding biological applications are summarized. Additionally, the challenges and potential of LOx-based nanomedicines are highlighted.

Oligo-Fucoidan supplementation enhances the effect of Olaparib on preventing metastasis and recurrence of triple-negative breast cancer in mice.

BACKGROUND: Seaweed polysaccharides have been recommended as anticancer supplements and for boosting human health; however, their benefits in the treatment of triple-negative breast cancers (TNBCs) and improving immune surveillance remain unclear. Olaparib is a first-in-class poly (ADP-ribose) polymerase inhibitor. Oligo-Fucoidan, a low-molecular-weight sulfated polysaccharide purified from brown seaweed (Laminaria japonica), exhibits significant bioactivities that may aid in disease management. METHODS: Macrophage polarity, clonogenic assays, cancer stemness properties, cancer cell trajectory, glucose metabolism, the TNBC 4T1 cells and a 4T1 syngeneic mouse model were used to inspect the therapeutic effects of olaparib and Oligo-Fucoidan supplementation on TNBC aggressiveness and microenvironment. RESULTS: Olaparib treatment increased sub-G1 cell death and G2/M arrest in TNBC cells, and these effects were enhanced when Oligo-Fucoidan was added to treat the TNBC cells. The levels of Rad51 and programmed death-ligand 1 (PD-L1) and the activation of epidermal growth factor receptor (EGFR) and adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) facilitate drug resistance and TNBC metastasis. However, the combination of olaparib and Oligo-Fucoidan synergistically reduced Rad51 and PD-L1 levels, as well as the activity of EGFR and AMPK; consistently, TNBC cytotoxicity and stemness were inhibited. Oligo-Fucoidan plus olaparib better inhibited the formation of TNBC stem cell mammospheroids with decreased subpopulations of CD44high/CD24low and EpCAMhigh cells than monotherapy. Importantly, Oligo-Fucoidan plus olaparib repressed the oncogenic interleukin-6 (IL-6)/p-EGFR/PD-L1 pathway, glucose uptake and lactate production. Oligo-Fucoidan induced immunoactive and antitumoral M1 macrophages and attenuated the side effects of olaparib, such as the promotion on immunosuppressive and protumoral M2 macrophages. Furthermore, olaparib plus Oligo-Fucoidan dramatically suppressed M2 macrophage invasiveness and repolarized M2 to the M0-like (F4/80high) and M1-like (CD80high and CD86high) phenotypes. In addition, olaparib- and Oligo-Fucoidan-pretreated TNBC cells resulted in the polarization of M0 macrophages into CD80(+) M1 but not CD163(+) M2 macrophages. Importantly, olaparib supplemented with oral administration of Oligo-Fucoidan in mice inhibited postsurgical TNBC recurrence and metastasis with increased cytotoxic T cells in the lymphatic system and decreased regulatory T cells and M2 macrophages in tumors. CONCLUSION: Olaparib supplemented with natural compound Oligo-Fucoidan is a novel therapeutic strategy for reprogramming cancer stemness, metabolism and the microenvironment to prevent local postsurgical recurrence and distant metastasis. The combination therapy may advance therapeutic efficacy that prevent metastasis, chemoresistance and mortality in TNBC patients.