Metformin sensitizes therapeutic agents and improves outcome in pre-clinical and clinical diffuse large B-cell lymphoma

Fatty Acid Metabolism Provides an Essential Survival Signal in OxPhos and BCR DLBCL Cells

Backgroung/objectives: Diffuse large B-cell lymphoma (DLBCL) is the most frequent subtype of malignant lymphoma and is a heterogeneous disease with various gene and chromosomal abnormalities. The development of novel therapeutic treatments has improved DLBCL prognosis, but patients with early relapse or refractory disease have a poor outcome (with a mortality of around 40%). Metabolic reprogramming is a hallmark of cancer cells. Fatty acid (FA) metabolism is frequently altered in cancer cells and recently emerged as a critical survival path for cancer cell survival. Methods: We first performed the metabolic characterization of an extended panel of DLBCL cell lines, including lipid droplet content. Then, we investigated the effect of drugs targeting FA metabolism on DLBCL cell survival. Further, we studied how the combination of drugs targeting FA and either mitochondrial metabolism or mTOR pathway impacts on DLBCL cell death. Results: Here, we reveal, using a large panel of DLBCL cell lines characterized by their metabolic status, that targeting of FA metabolism induces massive DLBCL cell death regardless of their OxPhos or BCR/glycolytic subtype. Further, FA drives resistance of DLBCL cell death induced by mitochondrial stress upon treatment with either metformin or L-asparaginase, two FDA-approved antimetabolic drugs. Interestingly, combining inhibition of FA metabolism with that of the mTOR oncogenic pathway strongly potentiates DLBCL cell death. Conclusion: Altogether, our data highlight the central role played by FA metabolism in DLBCL cell survival, independently of their metabolic subtype, and provide the framework for the use of drugs targeting this metabolic vulnerability to overcome resistance in DLBCL patients.

Single and Combinatorial Effects of Metformin and Thymoquinone in Diffuse Large B Cell Lymphoma Cells

Diffuse large B cell lymphoma (DLBCL) is classified into Germinal Center B-cell (GCB) and activated B-cell (ABC) subgroups originating from different stages of lymphoid differentiation. Cell of origin dictates the behavior and therapeutic response of DLBCL. This study aimed to evaluate single and combinatorial effects of metformin and thymoquinone (TQ) in two DLBCL cell lines belonging to GCB and ABC subtypes. Metformin and TQ caused dose-dependent responses in both ABC and GCB DLBCL subtypes. Metformin had a greater impact on the ABC subtype while TQ demonstrated more pronounced effects on the GCB subtype. Synergistic effects were observed in the DHL4 (GCB subtype) but not in the HBL1 (ABC subtype) cell line. This is the first study to compare the effects of metformin and TQ in ABC versus GCB subtype of DLBCL. It brings valuable results that could be utilized in further research aimed at reshaping treatments for subtype-specific lymphomas.

Metabolic Heterogeneity in Diffuse Large B-Cell Lymphoma Cells Reveals an Innovative Antimetabolic Combination Strategy

Background/Objectives: Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma, characterized by aggressive and heterogeneous tumors originating from B-cells. Especially in patients with relapsed or refractory (R/R) disease, DLBCL remains a challenging cancer to treat. Metabolic reprogramming is a hallmark of malignant cells. Our research focuses on developing strategies to enhance clinical outcomes for R/R DLBCL patients by targeting metabolic vulnerabilities. Methods: We investigated the effects of combining metformin and L-asparaginase, two FDA-approved antimetabolic drugs, on DLBCL cell metabolism and survival. Nuclear magnetic resonance (NMR) spectroscopy was employed to assess metabolic disturbances induced by the drug combination. The impact on lipid metabolism, glycolysis, glutaminolysis, the tricarboxylic acid (TCA) cycle, and antioxidant responses was examined. Induction of apoptosis was evaluated by FACS analysis. Results: The combination of metformin and L-asparaginase strongly sensitized DLBCL cells to apoptosis, independently of their oxidative phosphorylation (OxPhos) or BCR/glycolytic status. NMR spectroscopy revealed that this combination induces broader metabolic disturbances than either drug alone. It disrupts lipid metabolism by altering levels of phospholipids, cholesterol, and fatty acids. Additionally, it counteracts the pro-glycolytic effect of metformin, decreases glycolysis, and reduces glutaminolysis. It also affects the TCA cycle and antioxidant responses, critical for cellular energy production and redox balance. Furthermore, this combination interferes with two key cancer survival pathways, mTORC1 and MAPK signaling. Importantly, proof of principle for its beneficial effect was demonstrated in DLBCL patients. Conclusions: Combining metformin and L-asparaginase affects DLBCL cell survival by targeting multiple metabolic pathways and may represent a novel therapeutic approach for R/R DLBCL patients.

Anti-Diabetic Therapies and Cancer: From Bench to Bedside

Diabetes mellitus (DM) is a significant risk factor for various cancers, with the impact of anti-diabetic therapies on cancer progression differing across malignancies. Among these therapies, metformin has gained attention for its potential anti-cancer effects, primarily through modulation of the AMP-activated protein kinase/mammalian target of rapamycin (AMPK/mTOR) pathway and the induction of autophagy. Beyond metformin, other conventional anti-diabetic treatments, such as insulin, sulfonylureas (SUs), pioglitazone, and dipeptidyl peptidase-4 (DPP-4) inhibitors, have also been examined for their roles in cancer biology, though findings are often inconclusive. More recently, novel medications, like glucagon-like peptide-1 (GLP-1) receptor agonists, dual GLP-1/glucose-dependent insulinotropic polypeptide (GIP) agonists, and sodium-glucose co-transporter-2 (SGLT-2) inhibitors, have revolutionized DM management by not only improving glycemic control but also delivering substantial cardiovascular and renal benefits. Given their diverse metabolic effects, including anti-obesogenic properties, these novel agents are now under meticulous investigation for their potential influence on tumorigenesis and cancer advancement. This review aims to offer a comprehensive exploration of the evolving landscape of glucose-lowering treatments and their implications in cancer biology. It critically evaluates experimental evidence surrounding the molecular mechanisms by which these medications may modulate oncogenic signaling pathways and reshape the tumor microenvironment (TME). Furthermore, it assesses translational research and clinical trials to gauge the practical relevance of these findings in real-world settings. Finally, it explores the potential of anti-diabetic medications as adjuncts in cancer treatment, particularly in enhancing the efficacy of chemotherapy, minimizing toxicity, and addressing resistance within the framework of immunotherapy.

Assessing the antitumor effects of metformin on ovarian clear cell carcinoma

Developing novel therapies that outperform the existing chemotherapeutic treatments is required for treatment-resistant ovarian clear cell carcinoma. We investigated the antitumor effect of metformin on ovarian clear cell carcinoma, enhancement of the antitumor effect by its combination with chemotherapy, and its molecular regulatory mechanism. First, we evaluated the viability of ovarian clear cell carcinoma lines using the water-soluble tetrazolium-1 assay and found that metformin suppressed cell viability. Cell viability was significantly suppressed by co-treatment with cisplatin and metformin. In contrast, co-treatment with paclitaxel and metformin showed no significant difference in viability compared with the group without metformin. Western blot analysis showed increased phosphorylation of AMP-activated protein kinase in some cell lines and suppressed phosphorylation of the mammalian target of rapamycin in a particular cell line. Flow cytometry analysis revealed a significant increase in the rate of apoptosis in the metformin-treated group and rate of cell cycle arrest at the G2/M phase in a particular cell line. These results indicated that metformin may be effective against cultured ovarian clear cell carcinoma cells, particularly in combination with cisplatin.

Metformin in Combination with Standard Therapy in Patients with Diffuse Large B-Cell Lymphoma: A Randomized Phase II Clinical Trial

BACKGROUND

Metformin has been shown to have antitumor activity in different tumor types. In DLBCL (Diffuse large B cell lymphoma), using metformin with front-line chemotherapy & immunotherapy resulted in improved clinical outcomes.

OBJECTIVES

To assess the effectiveness of incorporating metformin into the standard initial treatment regimen of R-CHOP for patients with DLBCL. The evaluation metrics included response rate, toxicity, progression-free survival (PFS), and overall survival (OS).

PATIENTS AND METHODS

This prospective phase 2 trial included 100 adult patients with histopathological evidence of DLBCL, eligible for first-line treatment with R-CHOP, life expectancy of at least 6 months, and performance status (PS) ≤ 2. Patients were randomized to receive either metformin plus R-CHOP or R-CHOP alone.

RESULTS

Each group included 50 patients. The metformin arm had more females than the standard arm (p=0.016). Nausea was significantly higher in the test arm than the standard arm (p=0.008). Metformin group had higher rates of complete remission (CR) at the end of treatment (92% vs 74%; p=0.017), lower rates of relapse/progression (10% vs 36%; p=0.002), and lower rates of overall mortality (4% vs 20%; p=0.014). The mean disease-free survival (DFS) was 24.5 months in the metformin group versus 20.2 months in the control arm (p=0.023). Likewise, the mean progression-free survival (PFS) was 25.91 versus 19.81 months and the mean overall survival (OS) was 27.39 versus 23.8 months (p-values= 0.002, and 0.013 respectively). By multivariate analysis of response and relapse, the use of metformin was an independent prognostic factor of CR and relapse.

CONCLUSIONS

The addition of metformin to standard R-CHOP could improve clinical outcomes in patients with DLBCL with a tolerable safety profile.

Single-cell and spatial transcriptomics reveal a high glycolysis B cell and tumor-associated macrophages cluster correlated with poor prognosis and exhausted immune microenvironment in diffuse large B-cell lymphoma

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous malignancy characterized by varied responses to treatment and prognoses. Understanding the metabolic characteristics driving DLBCL progression is crucial for developing personalized therapies.

METHODS

This study utilized multiple omics technologies including single-cell transcriptomics (n = 5), bulk transcriptomics (n = 966), spatial transcriptomics (n = 10), immunohistochemistry (n = 34), multiple immunofluorescence (n = 20) and to elucidate the metabolic features of highly malignant DLBCL cells and tumor-associated macrophages (TAMs), along with their associated tumor microenvironment. Metabolic pathway analysis facilitated by scMetabolism, and integrated analysis via hdWGCNA, identified glycolysis genes correlating with malignancy, and the prognostic value of glycolysis genes (STMN1, ENO1, PKM, and CDK1) and TAMs were verified.

RESULTS

High-glycolysis malignant DLBCL tissues exhibited an immunosuppressive microenvironment characterized by abundant IFN_TAMs (CD68+CXCL10+PD-L1+) and diminished CD8+ T cell infiltration. Glycolysis genes were positively correlated with malignancy degree. IFN_TAMs exhibited high glycolysis activity and closely communicating with high-malignancy DLBCL cells identified within datasets. The glycolysis score, evaluated by seven genes, emerged as an independent prognostic factor (HR = 1.796, 95% CI: 1.077-2.995, p = 0.025 and HR = 2.631, 95% CI: 1.207-5.735, p = 0.015) along with IFN_TAMs were positively correlated with poor survival (p < 0.05) in DLBCL. Immunohistochemical validation of glycolysis markers (STMN1, ENO1, PKM, and CDK1) and multiple immunofluorescence validation of IFN_TAMs underscored their prognostic value (p < 0.05) in DLBCL.

CONCLUSIONS

This study underscores the significance of glycolysis in tumor progression and modulation of the immune microenvironment. The identified glycolysis genes and IFN_TAMs represent potential prognostic markers and therapeutic targets in DLBCL.

Metformin as anticancer agent and adjuvant in cancer combination therapy: Current progress and future prospect

Metformin, as the preferred antihyperglycemic drug for type 2 diabetes, has been found to have a significant effect in inhibiting tumor growth in recent years. However, metformin alone in cancer treatment has the disadvantages of high dose concentrations and few targeted cancer types. Increasing studies have confirmed that metformin can be used in combination with conventional anticancer therapy to obtain more promising clinical benefits, which is expected to be rapidly transformed and applied in clinic. Some combination therapy strategies including metformin combined with chemotherapy, radiotherapy, targeted therapy and immunotherapy have been proven to have more significant antitumor effects and longer survival time than monotherapy. In this review, we summarize the synergistic antitumor effects and mechanisms of metformin in combination with other current conventional anticancer therapies. In addition, we update the research progress and the latest prospect of the metformin-combined application in the cancer treatment. This work could provide more evidence and future direction for the clinical application of metformin in antitumor.

Restricting Colorectal Cancer Cell Metabolism with Metformin: An Integrated Transcriptomics Study

BACKGROUND

Metformin is a first-line therapy for type 2 diabetes as it disrupts cellular metabolism. Despite the association between metformin and lower cancer incidence, the anti-tumour activity of the drug in colorectal cancer (CRC) is incompletely understood. This study identifies underlying molecular mechanisms by which metformin slows colorectal cancer cell proliferation by investigating metformin-associated microRNA (miRNA) and target gene pairs implicated in signalling pathways.

METHODS

The present study analysed changes in miRNAs and the coding transcriptome in CRC cells treated with a sublethal dose of metformin, followed by the contextual validation of potential miRNA-target gene pairs.

RESULTS

Analyses of small RNA and transcriptome sequencing data revealed 104 miRNAs and 1221 mRNAs to be differentially expressed in CRC cells treated with metformin for 72 h. Interaction networks between differentially expressed miRNAs and putative target mRNAs were identified. Differentially expressed genes were mainly implicated in metabolism and signalling processes, such as the PI3K-Akt and MAPK/ERK pathways. Further validation of potential miRNA-target mRNA pairs revealed that metformin induced miR-2110 and miR-132-3p to target PIK3R3 and, consequently, regulate CRC cell proliferation, cell cycle progression and the PI3K-Akt signalling pathway. Metformin also induced miR-222-3p and miR-589-3p, which directly target STMN1 to inhibit CRC cell proliferation and cell cycle progression.

CONCLUSIONS

This study identified novel changes in the coding transcriptome and small non-coding RNAs associated with metformin treatment of CRC cells. Integration of these datasets highlighted underlying mechanisms by which metformin impedes cell proliferation in CRC. Importantly, it identified the post-transcriptional regulation of specific genes that impact both metabolism and cell proliferation.

Self-Adjuvanting Polyguanidine Nanovaccines for Cancer Immunotherapy

Tapping into the innate immune system's power, nanovaccines can induce tumor-specific immune responses, which is a promising strategy in cancer immunotherapy. However, traditional vaccine design, requiring simultaneous loading of antigens and adjuvants, is complex and poses challenges for mass production. Here, we developed a tumor nanovaccine platform that integrates adjuvant functions into the delivery vehicle, using branched polyguanidine (PolyGu) nanovaccines. These nanovaccines were produced by modifying polyethylenimine (PEI) with various guanidine groups, transforming PEI's cytotoxicity into innate immune activation. The PolyGu nanovaccines based on poly(phenyl biguanidine ) (Poly-PBG) effectively stimulated dendritic cells, promoted their maturation via the TLR4 and NLRP3 pathways, and displayed robust in vivo immune activity. They significantly inhibited tumor growth and extended mouse survival. The PolyGu also showed promise for constructing more potent mRNA-based nanovaccines, offering a platform for personalized cancer vaccine. This work advances cancer immunotherapy toward potential clinical application by introducing a paradigm for developing self-adjuvanting nanovaccines.

Metformin and risk of hematological cancers in patients with diabetes: a systematic review and meta-analysis

FUNDING

No external funding.

The Association of Metformin With Heart Failure in Patients With Diabetes Mellitus Receiving Anthracycline Chemotherapy

Background

The prevention of heart failure (HF) is an important issue in patients treated with anthracyclines. Metformin, widely used to treat diabetes mellitus (DM), protects from anthracycline-induced cardiotoxicity in vitro and in animal models.

Objectives

The aim of our study was to test the association of metformin with the occurrence of symptomatic HF in patients with DM receiving anthracyclines.

Methods

A total of 561 patients with DM received new anthracycline therapy between 2008 and 2021 in a tertiary care center; propensity score matching was used to compare patients with or without metformin treatment. The primary outcome was new onset symptomatic HF occurring within 1 year of the initiation of anthracyclines.

Results

A total of 315 patients (65 ± 11 years of age, 33.7% male) were included. Patients with and without metformin were well matched for age, sex, type of cancer, medications, and cardiovascular risk factors. Six patients treated with metformin and 17 matched patients developed HF within 1 year of anthracycline initiation. The incidence of HF in patients treated with metformin was lower than patients without metformin within 1 year after anthracyclines (cumulative incidence: 3.6% vs 10.5%; P = 0.022; HR: 0.35; 95% CI: 0.14-0.90; P = 0.029). The use of metformin (HR: 0.71; 95% CI: 0.50-1.00; P = 0.049), was also associated with lower mortality.

Conclusions

The use of metformin was associated with a lower incidence of HF and overall mortality in patients with DM receiving anthracyclines. Our findings should be further confirmed by randomized control trials.

Repurposing Metformin in hematologic tumor: State of art

Metformin is an ancient drug for the treatment of type 2 diabetes, and many studies now suggested that metformin can be used as an adjuvant drug in the treatment of many types of tumors. The mechanism of action of metformin for tumor treatment mainly involves: 1. activation of AMPK signaling pathway 2. inhibition of DNA damage repair in tumor cells 3. downregulation of IGF-1 expression 4. inhibition of chemoresistance and enhancement of chemotherapy sensitivity in tumor cells 5. enhancement of antitumor immunity 6. inhibition of oxidative phosphorylation (OXPHOS). Metformin also plays an important role in the treatment of hematologic tumors, especially in leukemia, lymphoma, and multiple myeloma (MM). The combination of metformin and chemotherapy enhances the efficacy of chemotherapy, and metformin reduces the progression of monoclonal gammopathy of undetermined significance (MGUS) to MM. The purpose of this review is to summarize the anticancer mechanism of metformin and the role and mechanism of action of metformin in hematologic tumors. We mainly summarize the studies related to metformin in hematologic tumors, including cellular experiments and animal experiments, as well as controlled clinical studies and clinical trials. In addition, we also focus on the possible side effects of metformin. Although a large number of preclinical and clinical studies have been performed and the role of metformin in preventing the progression of MGUS to MM has been demonstrated, metformin has not been approved for the treatment of hematologic tumors, which is related to the adverse effects of its high-dose application. Low-dose metformin reduces adverse effects and has been shown to alter the tumor microenvironment and enhance antitumor immune response, which is one of the main directions for future research.

Metabolic Reprogramming and Potential Therapeutic Targets in Lymphoma

Lymphoma is a heterogeneous group of diseases that often require their metabolism program to fulfill the demand of cell proliferation. Features of metabolism in lymphoma cells include high glucose uptake, deregulated expression of enzymes related to glycolysis, dual capacity for glycolytic and oxidative metabolism, elevated glutamine metabolism, and fatty acid synthesis. These aberrant metabolic changes lead to tumorigenesis, disease progression, and resistance to lymphoma chemotherapy. This metabolic reprogramming, including glucose, nucleic acid, fatty acid, and amino acid metabolism, is a dynamic process caused not only by genetic and epigenetic changes, but also by changes in the microenvironment affected by viral infections. Notably, some critical metabolic enzymes and metabolites may play vital roles in lymphomagenesis and progression. Recent studies have uncovered that metabolic pathways might have clinical impacts on the diagnosis, characterization, and treatment of lymphoma subtypes. However, determining the clinical relevance of biomarkers and therapeutic targets related to lymphoma metabolism is still challenging. In this review, we systematically summarize current studies on metabolism reprogramming in lymphoma, and we mainly focus on disorders of glucose, amino acids, and lipid metabolisms, as well as dysregulation of molecules in metabolic pathways, oncometabolites, and potential metabolic biomarkers. We then discuss strategies directly or indirectly for those potential therapeutic targets. Finally, we prospect the future directions of lymphoma treatment on metabolic reprogramming.

Action Mechanism of Metformin and Its Application in Hematological Malignancy Treatments: A Review

Hematologic malignancies (HMs) mainly include acute and chronic leukemia, lymphoma, myeloma and other heterogeneous tumors that seriously threaten human life and health. The common effective treatments are radiotherapy, chemotherapy and hematopoietic stem cell transplantation (HSCT), which have limited options and are prone to tumor recurrence and (or) drug resistance. Metformin is the first-line drug for the treatment of type 2 diabetes (T2DM). Recently, studies identified the potential anti-cancer ability of metformin in both T2DM patients and patients that are non-diabetic. The latest epidemiological and preclinical studies suggested a potential benefit of metformin in the prevention and treatment of patients with HM. The mechanism may involve the activation of the adenosine monophosphate-activated protein kinase (AMPK) signaling pathway by metformin as well as other AMPK-independent pathways to exert anti-cancer properties. In addition, combining current conventional anti-cancer drugs with metformin may improve the efficacy and reduce adverse drug reactions. Therefore, metformin can also be used as an adjuvant therapeutic agent for HM. This paper highlights the anti-hyperglycemic effects and potential anti-cancer effects of metformin, and also compiles the in vitro and clinical trials of metformin as an anti-cancer and chemosensitizing agent for the treatment of HM. The need for future research on the use of metformin in the treatment of HM is indicated.

Current Status of Novel Agents for the Treatment of B Cell Malignancies: What's Coming Next?

Resistance to death is one of the hallmarks of human B cell malignancies and often contributes to the lack of a lasting response to today's commonly used treatments. Drug discovery approaches designed to activate the death machinery have generated a large number of inhibitors of anti-apoptotic proteins from the B-cell lymphoma/leukemia 2 family and the B-cell receptor (BCR) signaling pathway. Orally administered small-molecule inhibitors of Bcl-2 protein and BCR partners (e.g., Bruton's tyrosine kinase and phosphatidylinositol-3 kinase) have already been included (as monotherapies or combination therapies) in the standard of care for selected B cell malignancies. Agonistic monoclonal antibodies and their derivatives (antibody-drug conjugates, antibody-radioisotope conjugates, bispecific T cell engagers, and chimeric antigen receptor-modified T cells) targeting tumor-associated antigens (TAAs, such as CD19, CD20, CD22, and CD38) are indicated for treatment (as monotherapies or combination therapies) of patients with B cell tumors. However, given that some patients are either refractory to current therapies or relapse after treatment, novel therapeutic strategies are needed. Here, we review current strategies for managing B cell malignancies, with a focus on the ongoing clinical development of more effective, selective drugs targeting these molecules, as well as other TAAs and signaling proteins. The observed impact of metabolic reprogramming on B cell pathophysiology highlights the promise of targeting metabolic checkpoints in the treatment of these disorders.

Activation of the Anaphase Promoting Complex Reverses Multiple Drug Resistant Cancer in a Canine Model of Multiple Drug Resistant Lymphoma

Simple Summary

Multiple drug resistant cancers develop all too soon in patients who received successful cancer treatment. A lack of treatment options often leaves palliative care as the last resort. We tested whether the insulin sensitizer, metformin, known to have anti-cancer activity, could impact canines with drug resistant lymphoma when added to chemotherapy. All canines in the study expressed protein markers of drug resistance and within weeks of receiving metformin, the markers were decreased. A microarray was performed, and from four canines assessed, a common set of 290 elevated genes were discovered in tumor cells compared to control cells. This cluster was enriched with genes that stall the cell cycle, with a large component representing substrates of the Anaphase Promoting Complex (APC), which degrades proteins. One canine entered partial remission. RNAs from this canine showed that APC substrates were decreased during remission and elevated again during relapse, suggesting that the APC was impaired in drug resistant canines and restored when remission occurred. We validated our results in cell lines using APC inhibitors and activators. We conclude that the APC may be a vital guardian of the genome and could delay the onset of multiple drug resistance when activated.

Abstract

Like humans, canine lymphomas are treated by chemotherapy cocktails and frequently develop multiple drug resistance (MDR). Their shortened clinical timelines and tumor accessibility make canines excellent models to study MDR mechanisms. Insulin-sensitizers have been shown to reduce the incidence of cancer in humans prescribed them, and we previously demonstrated that they also reverse and delay MDR development in vitro. Here, we treated canines with MDR lymphoma with metformin to assess clinical and tumoral responses, including changes in MDR biomarkers, and used mRNA microarrays to determine differential gene expression. Metformin reduced MDR protein markers in all canines in the study. Microarrays performed on mRNAs gathered through longitudinal tumor sampling identified a 290 gene set that was enriched in Anaphase Promoting Complex (APC) substrates and additional mRNAs associated with slowed mitotic progression in MDR samples compared to skin controls. mRNAs from a canine that went into remission showed that APC substrate mRNAs were decreased, indicating that the APC was activated during remission. In vitro validation using canine lymphoma cells selected for resistance to chemotherapeutic drugs confirmed that APC activation restored MDR chemosensitivity, and that APC activity was reduced in MDR cells. This supports the idea that rapidly pushing MDR cells that harbor high loads of chromosome instability through mitosis, by activating the APC, contributes to improved survival and disease-free duration.

Plasma Metabolites Forecast Occurrence and Prognosis for Patients With Diffuse Large B-Cell Lymphoma

Background

Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin’s lymphoma with considerable heterogeneity and different clinical prognosis. However, plasma metabomics used to forecast occurrence and prognosis of DLBCL are rarely addressed.

Method

A total of 65 volunteers including 22 healthy controls (Ctrl), 25 DLBCL patients newly diagnosed (ND), and 18 DLBCL patients achieving complete remission (CR) were enrolled. A gas chromatography mass spectrometry-based untargeted plasma metabolomics analysis was performed.

Results

Multivariate statistical analysis displayed distinct metabolic features among Crtl, ND, and CR groups. Surprisingly, metabolic profiles of newly diagnosed DLBCL patients undergoing different prognosis showed clear and distinctive clustering. Based on the candidate metabolic biomarkers (glucose and aspartate) and clinical indicators (lymphocyte, red blood count, and hemoglobin), a distinct diagnostic equation was established showing improved diagnostic performance with an area under curve of 0.936. The enrichment of citric acid cycle, deficiency of branched chain amino acid, methionine, and cysteine in newly diagnosed DLBCL patients was closely associated with poor prognosis. In addition, we found that malate and 2-hydroxy-2-methylbutyric acid were positively correlated with the baseline tumor metabolic parameters (metabolically active tumor volume and total lesion glycolysis), and the higher abundance of plasma malate, the poorer survival.

Conclusion

Our preliminary data suggested plasma metabolomics study was informative to characterize the metabolic phenotypes and forecast occurrence and prognosis of DLBCL. Malate was identified as an unfavorable metabolic biomarker for prognosis-prediction of DLBCL, which provided a new insight on risk-stratification and therapeutic targets of DLBCL. More studies to confirm these associations and investigate potential mechanisms are in the process.

Metabolic Biomarkers Assessed with PET/CT Predict Sex-Specific Longitudinal Outcomes in Patients with Diffuse Large B-Cell Lymphoma

In many cancers, including lymphoma, males have higher incidence and mortality than females. Emerging evidence demonstrates that one mechanism underlying this phenomenon is sex differences in metabolism, both with respect to tumor nutrient consumption and systemic alterations in metabolism, i.e., obesity. We wanted to determine if visceral fat and tumor glucose uptake with fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) could predict sex-dependent outcomes in patients with diffuse large B-cell lymphoma (DLBCL). We conducted a retrospective analysis of 160 patients (84 males; 76 females) with DLBCL who had imaging at initial staging and after completion of therapy. CT-based relative visceral fat area (rVFA), PET-based SUVmax normalized to lean body mass (SULmax), and end-of-treatment FDG-PET 5PS score were calculated. Increased rVFA at initial staging was an independent predictor of poor OS only in females. At the end of therapy, increase in visceral fat was a significant predictor of poor survival only in females. Combining the change in rVFA and 5PS scores identified a subgroup of females with visceral fat gain and high 5PS with exceptionally poor outcomes. These data suggest that visceral fat and tumor FDG uptake can predict outcomes in DLBCL patients in a sex-specific fashion.

Metformin and Cancer, an Ambiguanidous Relationship

The deregulation of energetic and cellular metabolism is a signature of cancer cells. Thus, drugs targeting cancer cell metabolism may have promising therapeutic potential. Previous reports demonstrate that the widely used normoglycemic agent, metformin, can decrease the risk of cancer in type 2 diabetics and inhibit cell growth in various cancers, including pancreatic, colon, prostate, ovarian, and breast cancer. While metformin is a known adenosine monophosphate-activated protein kinase (AMPK) agonist and an inhibitor of the electron transport chain complex I, its mechanism of action in cancer cells as well as its effect on cancer metabolism is not clearly established. In this review, we will give an update on the role of metformin as an antitumoral agent and detail relevant evidence on the potential use and mechanisms of action of metformin in cancer. Analyzing antitumoral, signaling, and metabolic impacts of metformin on cancer cells may provide promising new therapeutic strategies in oncology.

Epigenetic, Metabolic, and Immune Crosstalk in Germinal-Center-Derived B-Cell Lymphomas: Unveiling New Vulnerabilities for Rational Combination Therapies

B-cell non-Hodgkin lymphomas (B-NHLs) are highly heterogenous by genetic, phenotypic, and clinical appearance. Next-generation sequencing technologies and multi-dimensional data analyses have further refined the way these diseases can be more precisely classified by specific genomic, epigenomic, and transcriptomic characteristics. The molecular and genetic heterogeneity of B-NHLs may contribute to the poor outcome of some of these diseases, suggesting that more personalized precision-medicine approaches are needed for improved therapeutic efficacy. The germinal center (GC) B-cell like diffuse large B-cell lymphomas (GCB-DLBCLs) and follicular lymphomas (FLs) share specific epigenetic programs. These diseases often remain difficult to treat and surprisingly do not respond advanced immunotherapies, despite arising in secondary lymphoid organs at sites of antigen recognition. Epigenetic dysregulation is a hallmark of GCB-DLBCLs and FLs, with gain-of-function (GOF) mutations in the histone methyltransferase EZH2, loss-of-function (LOF) mutations in histone acetyl transferases CREBBP and EP300, and the histone methyltransferase KMT2D representing the most prevalent genetic lesions driving these diseases. These mutations have the common effect to disrupt the interactions between lymphoma cells and the immune microenvironment, via decreased antigen presentation and responsiveness to IFN-γ and CD40 signaling pathways. This indicates that immune evasion is a key step in GC B-cell lymphomagenesis. EZH2 inhibitors are now approved for the treatment of FL and selective HDAC3 inhibitors counteracting the effects of CREBBP LOF mutations are under development. These treatments can help restore the immune control of GCB lymphomas, and may represent optimal candidate agents for more effective combination with immunotherapies. Here, we review recent progress in understanding the impact of mutant chromatin modifiers on immune evasion in GCB lymphomas. We provide new insights on how the epigenetic program of these diseases may be regulated at the level of metabolism, discussing the role of metabolic intermediates as cofactors of epigenetic enzymes. In addition, lymphoma metabolic adaptation can negatively influence the immune microenvironment, further contributing to the development of immune cold tumors, poorly infiltrated by effector immune cells. Based on these findings, we discuss relevant candidate epigenetic/metabolic/immune targets for rational combination therapies to investigate as more effective precision-medicine approaches for GCB lymphomas.

Metformin sensitizes leukemic cells to cytotoxic lymphocytes by increasing expression of intercellular adhesion molecule-1 (ICAM-1)

Solid tumor cells have an altered metabolism that can protect them from cytotoxic lymphocytes. The anti-diabetic drug metformin modifies tumor cell metabolism and several clinical trials are testing its effectiveness for the treatment of solid cancers. The use of metformin in hematologic cancers has received much less attention, although allogeneic cytotoxic lymphocytes are very effective against these tumors. We show here that metformin induces expression of Natural Killer G2-D (NKG2D) ligands (NKG2DL) and intercellular adhesion molecule-1 (ICAM-1), a ligand of the lymphocyte function-associated antigen 1 (LFA-1). This leads to enhance sensitivity to cytotoxic lymphocytes. Overexpression of anti-apoptotic Bcl-2 family members decrease both metformin effects. The sensitization to activated cytotoxic lymphocytes is mainly mediated by the increase on ICAM-1 levels, which favors cytotoxic lymphocytes binding to tumor cells. Finally, metformin decreases the growth of human hematological tumor cells in xenograft models, mainly in presence of monoclonal antibodies that recognize tumor antigens. Our results suggest that metformin could improve cytotoxic lymphocyte-mediated therapy.

Influence of Hyperglycemia on the Prognosis of Patients with Diffuse Large B-Cell Lymphoma

PURPOSE

To explore the effects of primary and secondary hyperglycemia and the application of the hypoglycemic drug metformin on the prognosis of patients with diffuse large B-cell lymphoma (DLBCL).

METHODS

We performed a retrospective analysis of 1767 DLBCL patients.Cox regression method was used for analysis to evaluate the prognostic factors, and the Kaplan-Meier method was used to draw a survival curve to analyze the effect of hyperglycemia and the hypoglycemic drug metformin on the progression-free survival (PFS) and overall survival (OS) of DLBCL patients.

RESULTS

Our study showed that patients with hyperglycemia tend to have higher age (age>60 years), high body mass index (BMI)(≥24kg/m²), late Ann Arbor stage (III-IV), high international prognostic index (IPI) (3-5 score), high lactic dehydrogenase (LDH) level (>250U/L), bulky disease and comorbidity. Hyperglycemia affects the survival time of the DLBCL population (PFS: adjusted HR 1.41, 95% CI: 1.16-1.70, P <0.001, OS: adjusted HR 1.33, 95% CI:1.09-1.61, P=0.004).Compared with the non-hyperglycemia group, the secondary hyperglycemia increase affects the prognosis of the DLBCL population (P<0.001). Compared with the secondary hyperglycemia group, the primary hyperglycemia group has a poor prognosis (P<0.05). For patients with DLBCL and hyperglycemia (732 patients in total), the use of metformin can improve their PFS and OS (PFS: adjusted HR 0.69, 95% CI: 0.49-0.96, P=0.028, OS: adjusted HR 0.68, 95% CI: 0.49-0.95, P=0.024).

CONCLUSION

Hyperglycemia and secondary hyperglycemia are related to the poor prognosis of DLBCL population.For patients with DLBCL combined with hyperglycemia, the application of metformin can improve survival rate.

Diabetes and the Prognosis in Patients With Non-Hodgkin Lymphoma: A Meta-analysis of Cohort Studies

BACKGROUND

Consensus lacks regarding the association between diabetes mellitus (DM) and the prognosis of patients with non-Hodgkin lymphoma (NHL). We aimed to systematically evaluate the above association, as well as the potential influence of metformin use in a meta-analysis of cohort studies.

MATERIALS AND METHODS

Cohort studies investigating the association between DM and survival outcomes of patients with NHL were included by search of electronic databases that included PubMed, Embase, and Web of Science. A random-effects model was adopted to combine the results.

RESULTS

Eight cohort studies including 8652 patients with NHL were analyzed. Compared to non-DM patients with NHL, DM was associated with poor overall survival (OS, hazard ratio [HR] = 1.49, 95% confidence interval [CI]: 1.18-1.89, P < .001, I² = 69%), progression-free survival (PFS, HR = 1.30, 95% CI: 1.09-1.56, P = .004, I² = 0%), and lymphoma-specific survival (LSS, HR = 1.86, 95% CI: 1.41-2.45, P < .001, I² = 0%). Subgroup analysis showed consistent results in patients with diffuse large B-cell lymphoma (DLBCL, HR = 1.42, 1.35, and 1.95 for outcomes of OS, PFS, and LSS, respectively; P values all <.05). However, the associations between DM and these survival outcomes became nonsignificant in subgroup analysis limited to DM patients with concurrent use of metformin (HR = 1.30, 1.12, and 1.43 for outcomes of OS, PFS, and LSS, respectively; P values all > .10).

CONCLUSIONS

DM is associated with poor survival outcomes in patients with B-cell NHL, which is consistent in patients with DLBCL. Concurrent metformin use in DM patients with NHL may be associated with improved survival outcomes.

Alteration of Cholesterol Metabolism by Metformin Is Associated With Improved Outcome in Type II Diabetic Patients With Diffuse Large B-Cell Lymphoma

Recent studies have demonstrated the benefits of metformin on patients with lymphomas. B-cell receptor (BCR)-PI3K-AKT pathway-dependent cholesterol synthesis may represent a positive feedback mechanism responsible for the pathogenesis of BCR-dependent diffuse large B-cell lymphomas (DLBCLs). Thus, restriction of lipid synthesis would affect the integrity of lipid-forming membranes and block the BCR signaling pathway. Our in vitro findings suggested that the blocking effect of metformin on BCR signaling pathway is possibly exerted via blocking the biosynthesis of cholesterol. A retrospective case-control study was subsequently conducted on type II diabetic patients with DLBCL who were on metformin. Metformin was identified to be associated with improved response rate and PFS in diabetic patients and appeared to be an effective therapeutic drug against DLBCL.

Metformin prevents BAFF activation of Erk1/2 from B-cell proliferation and survival by impeding mTOR-PTEN/Akt signaling pathway

B-cell activating factor (BAFF) is an essential cytokine for B-cell maturation, differentiation and survival, and excess BAFF induces aggressive or neoplastic B-cell disorders and contributes to development of autoimmune diseases. Metformin, an anti-diabetic drug, has recently garnered a great attention due to its anti-proliferative and immune-modulatory features. However, little is known regarding the effect of metformin on BAFF-stimulated B cells. Here, we show that metformin attenuated human soluble BAFF (hsBAFF)-induced cell proliferation and survival by blocking the Erk1/2 pathway in normal and B-lymphoid (Raji) cells. Pretreatment with U0126, knockdown of Erk1/2, or expression of dominant negative MKK1 strengthened metformin's inhibition of hsBAFF-activated Erk1/2 and B-cell proliferation/viability, whereas expression of constitutively active MKK1 rendered high resistance to metformin. Further investigation found that overexpression of wild type PTEN or ectopic expression of dominant negative Akt potentiated metformin's suppression of hsBAFF-induced Erk1/2 activation and proliferation/viability in Raji cells, implying a PTEN/Akt-dependent mechanism involved. Furthermore, we noticed that metformin hindered hsBAFF-activated mTOR pathway in B cells. Inhibition of mTOR with rapamycin or knockdown of mTOR enhanced metformin's suppression of hsBAFF-induced phosphorylation of S6K1, PTEN, Akt, and Erk1/2, as well as B-cell proliferation/viability. These results indicate that metformin prevents BAFF activation of Erk1/2 from cell proliferation and survival by impeding mTOR-PTEN/Akt signaling pathway in normal and neoplastic B-lymphoid cells. Our findings support that metformin has a great potential for prevention of excessive BAFF-induced aggressive B-cell malignancies and autoimmune diseases.

Metformin induces apoptosis and inhibits migration by activating the AMPK/p53 axis and suppressing PI3K/AKT signaling in human cervical cancer cells

Human cervical cancer is the fourth most common malignancy among women worldwide, and it is expected to result in 460,000 deaths per year by 2040. Moreover, patients with cervical cancer often display drug resistance and severe side effects; therefore, the development of effective novel chemotherapeutic agents is important. In the present study, the effects of metformin, a first-line therapeutic drug for type 2 diabetes mellitus, were evaluated in cervical cancer. Compared with the control group, metformin significantly inhibited cell viability and migration, and induced apoptosis and cell cycle arrest in human cervical cancer cell lines (CaSki and HeLa). Following metformin treatment, the protein expression levels of p-AMP-activated protein kinase (p-AMPK), which promotes cell death, and the tumor suppressor protein p-p53 were remarkably upregulated in CaSki and C33A cells compared with the control group. Furthermore, compared with the control group, metformin significantly suppressed the PI3K/AKT signaling pathway in CaSki, C33A and HeLa cells. Compound C (an AMPK inhibitor) significantly reversed the effects of metformin on CaSki, C33A and HeLa cell viability, and AMPK and p53 phosphorylation. The results of the present study suggested that metformin induced AMPK-mediated apoptosis, thus metformin may serve as a chemotherapeutic agent for human cervical cancer.