Non-tumor Cells Research Articles

Design, synthesis, and biological evaluation of novel halogenated chlorido[N,N′-bis(salicylidene)-1,2-bis(3-methoxyphenyl)ethylenediamine]iron(III) complexes as anticancer agents

Iron(III) complexes based on N,N´-bis(salicylidene)ethylenediamine (salene) scaffolds have demonstrated promising anticancer features like induction of ferroptosis, an iron dependent cell death. Since poor cellular uptake limits their therapeutical potential, this study aimed to enhance the lipophilic character of chlorido[N,N′-bis(salicylidene)-1,2-bis(3-methoxyphenyl)ethylenediamine]iron(III) complexes by introducing lipophilicity improving ligands such as fluorine (X1), chlorine (X2) and bromine (X3) in 5-position in the salicylidene moieties. After detailed characterization the binding to nucleophiles, logP values and cellular uptake were determined. The complexes were further evaluated regarding their biological activity on MDA-MB 231 mammary carcinoma, the non-tumorous SV-80 fibroblast, HS-5 stroma and MCF-10A mammary gland cell lines. Stability of the complexes in aqueous and biological environments was proven by the lack of interactions with amino acids and glutathione. Cellular uptake was positively correlated with the logP values, indicating that higher lipophilicity enhanced cellular uptake. The complexes induced strong antiproliferative and antimetabolic effects on MDA-MB 231 cells, but were inactive on all non-malignant cells tested. Generation of mitochondrial reactive oxygen species, increase of lipid peroxidation and induction of both ferroptosis and necroptosis were identified as mechanisms of action. In conclusion, halogenation of chlorido[N,N′-bis(salicylidene)-1,2-bis(3-methoxyphenyl)ethylenediamine]iron(III) complexes raises their lipophilic character resulting in improved cellular uptake.Graphical abstract

The impact of histone lactylation on the tumor microenvironment and metabolic pathways and its potential in cancer therapy.

The complexity of cancer is intricately linked to its multifaceted biological processes, including the roles of the tumor microenvironment (TME) as well as genetic and metabolic regulation. Histone lactylation has recently emerged as a novel epigenetic modification mechanism that plays a pivotal role in regulating cancer initiation, proliferation, invasion, and metastasis. This review aims to elucidate the role of histone lactylation in modulating various aspects of tumor biology, including DNA repair mechanisms, glycolytic metabolic abnormalities, functions of non-tumor cells in the TME, and the promotion of tumor inflammatory responses and immune escape. Additionally, the review explores potential therapeutic strategies targeting histone lactylation. A comprehensive literature review was performed, analyzing recent findings on histone lactylation and its impact on cancer biology. This involved a systematic examination of studies focusing on biochemical pathways, cellular interactions, and clinical implications related to histone lactylation. Histone lactylation was identified as a critical regulator of tumor cell DNA repair mechanisms and glycolytic metabolic abnormalities. It also significantly influences the functions of non-tumor cells within the TME, promoting tumor inflammatory responses and immune escape. Moreover, histone lactylation acts as a multifunctional biological signaling molecule impacting immune responses within the TME. Various cell types within the TME, including T cells and macrophages, were found to regulate tumor growth and immune escape mechanisms through lactylation. Histone lactylation offers a novel perspective on tumor metabolism and its role in cancer development. It presents promising opportunities for the development of innovative cancer therapies. This review underscores the potential of histone lactylation as a therapeutic target, paving the way for new strategies in cancer treatment.

Single-cell RNA sequencing and cell-cell communication analysis reveal tumor microenvironment associated with chemotherapy responsiveness in ovarian cancer.

To investigate the impact of the tumor microenvironment (TME) on the responsiveness to chemotherapy in ovarian cancer (OV). We integrated single cell RNA-seq datasets of OV containing chemo-response information, and characterize their clusters based on different TME sections. We focus on analyzing cell-cell communication to elaborate on the mechanisms by which different components of the TME directly influence the chemo-response of tumor cells. scRNA-seq datasets were annotated according to specific markers for different cell types. Differential analysis of malignant epithelial cells revealed that chemoresistance was associated with the TME. Notably, distinct TME components exhibited varying effects on chemoresistance. Enriched SPP1+ tumor-associated macrophages in chemo-resistant patients could promote chemoresistance through SPP1 binding to CD44 on tumor cells. Additionally, the overexpression of THBS2 in stromal cells could promote chemoresistance through binding with CD47 on tumor cells. In contrast, GZMA in the lymphocytes could downregulate the expression of PARD3 through direct interaction with PARD3, thereby attenuating chemoresistance in tumor cells. Our study indicates that the non-tumor cell components of the TME (e.g. SPP1+ TAMs, stromal cells and lymphocytes) can directly impact the chemo-response of OV and targeting the TME was potentially crucial in chemotherapy of OV.

Integrative single-cell RNA-seq and spatial transcriptomics analyses reveal diverse apoptosis-related gene expression profiles in EGFR-mutated lung cancer

In EGFR-mutated lung cancer, the duration of response to tyrosine kinase inhibitors (TKIs) is limited by the development of acquired drug resistance. Despite the crucial role played by apoptosis-related genes in tumor cell survival, how their expression changes as resistance to EGFR-TKIs emerges remains unclear. Here, we conduct a comprehensive analysis of apoptosis-related genes, including BCL-2 and IAP family members, using single-cell RNA sequence (scRNA-seq) and spatial transcriptomics (ST). scRNA-seq of EGFR-mutated lung cancer cell lines captures changes in apoptosis-related gene expression following EGFR-TKI treatment, most notably BCL2L1 upregulation. scRNA-seq of EGFR-mutated lung cancer patient samples also reveals high BCL2L1 expression, specifically in tumor cells, while MCL1 expression is lower in tumors compared to non-tumor cells. ST analysis of specimens from transgenic mice with EGFR-driven lung cancer indicates spatial heterogeneity of tumors and corroborates scRNA-seq findings. Genetic ablation and pharmacological inhibition of BCL2L1/BCL-XL overcome or delay EGFR-TKI resistance. Overall, our findings indicate that BCL2L1/BCL-XL expression is important for tumor cell survival as EGFR-TKI resistance emerges.

IRF8-driven reprogramming of the immune microenvironment enhances anti-tumor adaptive immunity and reduces immunosuppression in murine glioblastoma.

Glioblastoma (GBM) has a highly immunosuppressive tumor immune microenvironment (TIME), largely mediated by myeloid-derived suppressor cells (MDSCs). Here, we utilized a retroviral replicating vector (RRV) to deliver Interferon Regulatory Factor 8 (IRF8), a master regulator of type 1 conventional dendritic cell (cDC1) development, in a syngeneic murine GBM model. We hypothesized that RRV-mediated delivery of IRF8 could "reprogram" intratumoral MDSCs into antigen-presenting cells (APCs) and thereby restore T-cell responses. Effects of RRV-IRF8 on survival and tumor growth kinetics were examined in the SB28 murine GBM model. Immunophenotype was analyzed by flow cytometry and gene expression assays. We assayed functional immunosuppression and antigen presentation by ex vivo T-cell-myeloid co-culture. Intratumoral injection of RRV-IRF8 in mice bearing intracerebral SB28 glioma significantly suppressed the tumor growth and prolonged survival. RRV-IRF8 treated tumors exhibited significant enrichment of cDC1s and CD8+ T-cells. Additionally, myeloid cells derived from RRV-IRF8 tumors showed decreased expression of the immunosuppressive markers Arg1 and IDO1 and demonstrated reduced suppression of naïve T-cell proliferation in ex vivo co-culture, compared to controls. Furthermore, DCs from RRV-IRF8 tumors showed increased antigen presentation compared to those from control tumors. In vivo treatment with azidothymidine (AZT), a viral replication inhibitor, showed that IRF8 transduction in both tumor and non-tumor cells is necessary for survival benefit, associated with a reprogrammed, cDC1- and CD8 T-cell-enriched TIME. Our results indicate that reprogramming of glioma-infiltrating myeloid cells by in vivo expression of IRF8 may reduce immunosuppression and enhance antigen presentation, achieving improved tumor control.

Senescence-associated secretory phenotype regulation by dual drug delivery biomimetic nanoplatform for enhanced tumor chemotherapy

Many chemotherapies, which are still the main clinical treatment for primary tumors, will induce persistent DNA damage in non-tumor stromal cells, especially cancer-associated fibroblasts (CAFs), and activate them to secrete senescence associated secretory phenotype (SASP). The transition could further result in the formation of tumor immunosuppressive microenvironment and cause drug resistance of neighboring tumor cells. To solve this dilemma, a multi-functional biomimetic drug delivery system (named mPtP@Lipo) was rationally developed by combining CAFs reshaper ginsenoside 20(S)-protopanaxadiol (PPD) and cisplatin prodrug (PtLA) to inhibit tumor progression and the formation of SASP. To achieve effective delivery of these molecules deep into the desmoplastic tumor, fibroblast membrane was fused with liposomes as a targeting carrier. In vitro and in vivo results showed that mPtP@Lipo could penetrate deep into the tumor, reverse CAFs phenotype and inhibit SASP formation, which then blocked the immunosuppressive progresses and thus reinforced anti-tumor immune response. The combination of chemotherapeutics and CAFs regulator could achieve both tumor inhibition and tumor immune microenvironment remodeling. In conclusion, mPtP@Lipo provides a promising strategy for the comprehensive stromal-desmoplastic tumor treatment.

21 Unconventional mechanisms of action and resistance to rapalogs in renal cancer

Abstract Background Clear cell renal cell carcinoma (ccRCC) is a prevalent cancer type in the United States driven by inactivation of the von Hippel-Lindau (VHL) gene and with frequent hyperactivation of mammalian target of rapamycin complex 1 (mTORC1). Multiple drugs have been developed to target VEGF/VEGFR2 and mTORC1 for advanced RCC treatment. Two specific mTORC1 inhibitors, temsirolimus and everolimus (known as rapalogs), are FDA-approved for the treatment of RCC but their clinical efficacy is hindered by the emergence of resistance. Methods To study the development of rapalog resistance in RCC, we utilized patient-derived tumorgrafts (TGs) implanted in immunocompromised mice and treated the mice with rapamycin for prolonged periods to generate resistance. Resistance was studied by transplanting resistant tumors into additional cohorts of mice and establishing primary cultures. The impact of rapamycin on tumor growth and mTORC1 activity in both tumor and stromal cells was assessed using molecular techniques. To dissect the role of the tumor microenvironment (TME), we generated genetically engineered immunocompromised recipient mice with an mTOR inhibitor resistance mutation (S2035T). Coculture experiments were performed to further explore the interplay. Results Prolonged rapamycin treatment resulted in the development of resistance in TGs. Notably, this occurred despite persistent inhibition of mTORC1 in tumor cells. Resistance was transient and lost with subsequent transplantation and in cell culture. Surprisingly, resistance was accompanied by mTORC1 reactivation in the TME, specifically in cancer associated fibroblasts. Introducing an mTOR resistance mutation (S2035T) into recipient mice was sufficient to cause resistance. Co-culture experiments with fibroblasts further demonstrated that rapamycin-resistant mutant fibroblasts conferred resistance in tumor cells even in the absence of mTORC1 activity. Conclusions This study uncovers a critical role of the TME, in mediating the response and resistance to rapalogs in RCC. Our data show that inhibition of mTORC1 in non-tumor cells is essential for the anti-tumor activity of rapalogs. These findings shed light on why mTOR mutations are rarely observed in resistant RCC patients and highlight the significance of the TME in modulating drug response and resistance. Moreover, our study emphasizes the potential of targeting TME cells as a therapeutic strategy in RCC and possibly other cancers. DOD CDMRP Funding: yes

Phospholipid peroxidation in macrophage confers tumor resistance by suppressing phagocytic capability towards ferroptotic cells.

Ferroptosis holds significant potential for application in cancer therapy. However, ferroptosis inducers are not cell-specific and can cause phospholipid peroxidation in both tumor and non-tumor cells. This limitation greatly restricts the use of ferroptosis therapy as a safe and effective anticancer strategy. Our previous study demonstrated that macrophages can engulf ferroptotic cells through Toll-like receptor 2 (TLR2). Despite this advancement, the precise mechanism by which phospholipid peroxidation in macrophages affects their phagocytotic capability during treatment of tumors with ferroptotic agents is still unknown. Here, we utilized flow sorting combined with redox phospholipidomics to determine that phospholipid peroxidation in tumor microenvironment (TME) macrophages impaired the macrophages ability to eliminate ferroptotic tumor cells by phagocytosis, ultimately fostering tumor resistance to ferroptosis therapy. Mechanistically, the accumulation of phospholipid peroxidation in the macrophage endoplasmic reticulum (ER) repressed TLR2 trafficking to the plasma membrane and caused its retention in the ER by disrupting the interaction between TLR2 and its chaperone CNPY3. Subsequently, this ER-retained TLR2 recruited E3 ligase MARCH6 and initiated the proteasome-dependent degradation. Using redox phospholipidomics, we identified 1-steaoryl-2-15-HpETE-sn-glycero-3-phosphatidylethanolamine (SAPE-OOH) as the crucial mediator of these effects. Conclusively, our discovery elucidates a novel molecular mechanism underlying macrophage phospholipid peroxidation-induced tumor resistance to ferroptosis therapy and highlights the TLR2-MARCH6 axis as a potential therapeutic target for cancer therapy.

Tailored amino acid-derived ionic Liquids: Precision chemotherapy for tumors

A set of fourteen imidazolium ionic liquids, each derived from L-amino acids and featuring distinct hydrophobic and hydrophilic components, were synthesized and physicochemically characterized. Thermal analysis showed transition temperatures remaining below 100 °C, being the rigid solid to elastic solid transition temperatures between −27 °C to + 57 °C. The aggregation studies investigated by fluorescence in water and buffered media showed two critical micellar concentrations (CMC) in aqueous media for compounds 7, 8 and 9, with the formation of well-defined aggregates in the second step. The synthesized ILs were assessed for their effects on two cancer cell lines, namely human lung adenocarcinoma A-549 and colon adenocarcinoma HT-29, under both physiological and acidic pH conditions. Furthermore, the influence of the ILs on embryonic kidney cells (HEK-293) was investigated to assess their effect on non-cancerous cells. This study demonstrates that the manipulation of various design vectors allowed for the precise tuning of the structure of ILs, resulting in IC50 values within the micromolar range. ILs featuring a NC12 alkyl side chain in the amide consistently exhibited low IC50 values and a high degree of selectivity against non-tumoral cells under acidic pH conditions. Subsequent investigations were carried out to gain insights into the cellular-level mechanisms of action. These findings provide strong evidence that by meticulously adjusting the molecular structure of these functionalized ILs, it is possible to design potent and selective chemotherapeutic agents.

Tartrolon D induces immunogenic cell death in melanoma

Tartrolon D (TRL) is produced by Teredinibacter turnerae, a symbiotic cellulose-degrading bacteria in shipworm gills. Immunogenic cell death (ICD) induction contributes to a better and longer-lasting response to anticancer treatment. Tumor cells undergoing ICD trigger activation of the immune system, as a vaccine. AimsThis study aimed to evaluate ICD induction by TRL. Main methodsCell viability was evaluated by SRB assay. Cell stress, cell death, ICD features and antigen-presenting molecules were evaluated by flow cytometry and immunoblot. Key findingsTRL showed antiproliferative activity on 7 tumor cell lines (L929, HCT 116, B16–F10, WM293A, SK-MEL-28, PC-3M, and MCF-7) and a non-tumor cell (HEK293A), with an inhibition concentration mean (IC50) ranging from 0.03 μM to 13 μM. Metastatic melanomas, SK-MEL-28, B16–F10, and WM293A, were more sensitive cell lines, with IC50 ranging from 0.07 to 1.2 μM. TRL induced apoptosis along with autophagy and endoplasmic reticulum stress and release of typical damage-associated molecular patterns (DAMPs) of ICD such calreticulin, ERp57, and HSP70 exposure, and HMGB1 release. Additionally, melanoma B16–F10 exposed to TRL increased expression of antigen-presenting molecules MHC II and CD1d and induced activation of splenocytes of C57BL/6 mice. SignificanceIn spite of recent advances provided by target therapy and immunotherapy, advanced metastatic melanoma is incurable for more than half of patients. ICD inducers yield better and long-lasting responses to anticancer treatment. Our findings shed light on an anticancer candidate of marine origin that induces ICD in melanoma.

New Amphiphilic Terpolymers of N-Vinylpyrrolidone with Acrylic Acid and Triethylene Glycol Dimethacrylate as Promising Drug Delivery: Design, Synthesis and Biological Properties In Vitro.

The terpolymers of N-vinylpyrrolidone (VP) with acrylic acid and triethylene glycol methacrylate were synthesized with more than 90% yield by radical copolymerization in ethanol from monomeric mixtures of different molar composition (98:2:2, 95:5: 2 and 98:2:5) and their monomer composition, absolute molecular masses and hydrodynamic radii in aqueous media were determined. Using the MTT test, these terpolymers were established to be low toxic for non-tumor Vero cells and HeLa tumor cells. Polymer compositions of hydrophobic dye methyl pheophorbide a (MPP) based on studied terpolymers and linear polyvinylpyrrolidone (PVP) were obtained and characterized in water solution. Quantum-chemical modeling of the MPP-copolymer structures was conducted, and the possibility of hydrogen bond formation between terpolymer units and the MPP molecule was shown. Using fluorescence microscopy, the accumulation and distribution of polymer particles in non-tumor (FetMSC) and tumor (HeLa) cells was studied, and an increase in the accumulation of MPP with both types of particles was found.

Single-cell profiling of surface glycosphingolipids opens a new dimension for deconvolution of breast cancer intratumoral heterogeneity and phenotypic plasticity

Glycosylated sphingolipids (GSLs) are a diverse group of cellular lipids typically reported as being rare in normal mammary tissue. In breast cancer (BCa), GSLs have emerged as noteworthy markers associated with breast cancer stem cells, mediators of phenotypic plasticity, and contributors to cancer cell chemoresistance. GSLs are potential surface markers that can uniquely characterize the heterogeneity of the tumor microenvironment, including cancer cell subpopulations and epithelial–mesenchymal plasticity (EMP). In this study, mass spectrometry analyses of the total sphingolipidome in breast epithelial cells and their mesenchymal counterparts revealed increased levels of Gb3 in epithelial cells and significantly elevated GD2 levels in the mesenchymal phenotype. To elucidate if GSL-related epitopes on BCa cell surfaces reflect EMP and cancer status, we developed and rigorously validated a 12-color spectral flow cytometry panel. This panel enables the simultaneous detection of native GSL epitopes (Gb3, SSEA1, SSEA3, SSEA4, and GD2), epithelial–mesenchymal transition markers (EpCAM, TROP2, and CD9), and lineage markers (CD45, CD31, and CD90) at the single-cell level. Next, the established panel was used for the analysis of BCa primary tumors and revealed surface heterogeneity in SSEA1, SSEA3, SSEA4, GD2, and Gb3, indicative of native epitope presence also on non-tumor cells. These findings further highlighted the phenotype-dependent alterations in GSL surface profiles, with differences between epithelial and stromal cells in the tumor. This study provides novel insights into BCa heterogeneity, shedding light on the potential of native GSL-related epitopes as markers for EMP and cancer status in fresh clinical samples. The developed single-cell approach offers promising avenues for further exploration.

Glutathione overproduction mediates lymphoma initiating cells survival and has a sex-dependent effect on lymphomagenesis

Lymphoid tumor patients often exhibit resistance to standard therapies or experience relapse post-remission. Relapse is driven by Tumor Initiating Cells (TICs), a subset of tumor cells capable of regrowing the tumor and highly resistant to therapy. Growing cells in 3D gels is a method to discern tumorigenic cells because it strongly correlates with tumorigenicity. The finding that TICs, rather than differentiated tumor cells, grow in 3D gels offers a unique opportunity to unveil TIC-specific signaling pathways and therapeutic targets common to various cancer types. Here, we show that culturing lymphoid cells in 3D gels triggers reactive oxygen species (ROS) production, leading to non-tumor lymphoid cell death while enabling the survival and proliferation of a subset of lymphoma/leukemia cells, TICs or TIC-like cells. Treatment with the antioxidant N-acetylcysteine inhibits this lethality and promotes the growth of primary non-tumor lymphoid cells in 3D gels. A subset of lymphoma cells, characterized by an increased abundance of the antioxidant glutathione, escape ROS-induced lethality, a response not seen in non-tumor cells. Reducing glutathione production in lymphoma cells, either through pharmacological inhibition of glutamate cysteine ligase (GCL), the enzyme catalyzing the rate-limiting step in glutathione biosynthesis, or via knockdown of GCLC, the GCL catalytic subunit, sharply decreased cell growth in 3D gels and xenografts. Tumor cells from B-cell lymphoma/leukemia patients and λ-MYC mice, a B-cell lymphoma mouse model, overproduce glutathione. Importantly, pharmacological GCL inhibition hindered lymphoma growth in female λ-MYC mice, suggesting that this treatment holds promise as a therapeutic strategy for female lymphoma/leukemia patients.

Exploring the potential of tocopherols: mechanisms of action and perspectives in the prevention and treatment of breast cancer.

Currently, breast cancer is the most common cause of mortalitycaused by neoplasia in women worldwide. The unmet challenges of conventional cancer therapy are chemoresistance and lack of selectivity, which can lead to serious side effects in patients; therefore,new treatments based on natural compounds that serve as adjuvants in breast cancer therapyare urgently needed. Tocopherols are naturally occurring antioxidant compounds that have shown antitumor activity against several types of cancer, including breast cancer. This review summarizes the antitumoral activity of tocopherols, such as theantiproliferative, apoptotic, anti-invasive, and antioxidant effects of tocopherols, through different molecular mechanisms. According to the studies described, α-T, δ-T and γ-T are the most studied in breast tumor cells; however, α-T and γ-T show a more critical antitumor activity and significant potential as a complements to chemotherapeutic drugs against breast cancer, enhancing toxicity against tumor cells and preventing cytotoxicity in nontumor cells. However, the possible relationship between tocopherol intake, related to concentration,and the promotion of cancer in particular cases should not be ruled out, so additional studies are required to determine the correct dose to obtain the desired antitumor effect. Moreover, nanomicelles of D-α-tocopherol have promising potential as pharmaceutical excipients for drug delivery to improve the cytotoxicity and selectivity of first-line chemotherapeutics against breast cancer.

Crotoxin induces cytotoxic effects in human malignant melanoma cells in both native and detoxified forms.

Introduction: Melanoma, a highly aggressive skin cancer originating in melanocytes, poses a significant threat due to its metastatic potential. While progress has been made in treating melanoma with targeted therapies and immunotherapies, challenges persist. Crotoxin (CTX), the principal toxin in Crotalus durissus terrificus snake venom, exhibits various biological activities, including anti-tumoral effects across multiple cancers. However, its clinical use is limited by toxicity. Thus, exploring alternatives to mitigate adverse effects is crucial. Methods and Results: This study investigates the antitumoral potential of CTX in its native and in a detoxified form, in melanoma cells. Firstly, we demonstrated that detoxified CTX presented reduced phospholipase activity. Both forms proved to be more cytotoxic to SK-MEL-28 and MeWo melanoma cells than non-tumoral cells. In SK-MEL-28 cells, where cytotoxic effects were more pronounced, native and detoxified CTX induced increased necrosis and apoptosis rates. We also confirmed the apoptosis death demonstrated by the activation of caspase-3 and 7, and the formation of apoptotic bodies. Furthermore, both CTX caused cell cycle arrest at the G2/M phase, interfering with melanoma cell proliferation. Cell migration and invasion were also suppressed by both CTX. These results confirm the antitumoral potential of CTX. Discussion: The maintenance of the antiproliferative effects in the detoxified version, with reduced enzymatic activity often liked to harm effects, supports further studies to identify active parts of the molecule responsible for the interesting effects without causing substantial toxic events, contributing to the future use of CTX-derived drugs with safety and efficacy.

Synergistic Enhancement of Chemotherapy-Induced Cell Death and Antitumor Efficacy against Tumoral T-Cell Lymphoblasts by IMMUNEPOTENT CRP.

T-cell malignancies, including T-cell acute lymphoblastic leukemia (T-ALL) and T-cell lymphoblastic lymphoma (T-LBL), present significant challenges to treatment due to their aggressive nature and chemoresistance. Chemotherapies remain a mainstay for their management, but the aggressiveness of these cancers and their associated toxicities pose limitations. Immunepotent CRP (ICRP), a bovine dialyzable leukocyte extract, has shown promise in inducing cytotoxicity against various cancer types, including hematological cancers. In this study, we investigated the combined effect of ICRP with a panel of chemotherapies on cell line models of T-ALL and T-LBL (CEM and L5178Y-R cells, respectively) and its impact on immune system cells (peripheral blood mononuclear cells, splenic and bone marrow cells). Our findings demonstrate that combining ICRP with chemotherapies enhances cytotoxicity against tumoral T-cell lymphoblasts. ICRP + Cyclophosphamide (CTX) cytotoxicity is induced through a caspase-, reactive oxygen species (ROS)-, and calcium-dependent mechanism involving the loss of mitochondrial membrane potential, an increase in ROS production, and caspase activation. Low doses of ICRP in combination with CTX spare non-tumoral immune cells, overcome the bone marrow-induced resistance to CTX cell death, and improves the CTX antitumor effect in vivo in syngeneic Balb/c mice challenged with L5178Y-R. This led to a reduction in tumor volume and a decrease in Ki-67 proliferation marker expression and the granulocyte/lymphocyte ratio. These results set the basis for further research into the clinical application of ICRP in combination with chemotherapeutic regimens for improving outcomes in T-cell malignancies.

Novel Coumarin-Nucleobase Hybrids with Potential Anticancer Activity: Synthesis, In Vitro Cell-Based Evaluation, and Molecular Docking.

A new series of compounds planned by molecular hybridization of the nucleobases uracil and thymine, or the xanthine theobromine, with coumarins, and linked through 1,2,3-triazole heterocycles were evaluated for their in vitro anticancer activity against the human tumor cell lines: colon carcinoma (HCT116), laryngeal tumor cells (Hep-2), and lung carcinoma cells (A549). The hybrid compound 9a exhibited better activity in the series, showing an IC50 of 24.19 ± 1.39 μM against the HCT116 cells, with a selectivity index (SI) of 6, when compared to the cytotoxicity against the non-tumor cell line HaCat. The in silico search for pharmacological targets was achieved through molecular docking studies on all active compounds, which suggested that the synthesized compounds possess a high affinity to the Topoisomerase 1-DNA complex, supporting their antitumor activity. The in silico toxicity prediction studies suggest that the compounds present a low risk of causing theoretical mutagenic and tumorigenic effects. These findings indicate that molecular hybridization from natural derivative molecules is an interesting approach to seek new antitumor candidates.

Context-dependent roles for autophagy in myeloid cells in tumor progression.

Autophagy is known to suppress tumor initiation by removing genotoxic stresses in normal cells. Conversely, autophagy is also known to support tumor progression by alleviating metabolic stresses in neoplastic cells. Centered on this pro-tumor role of autophagy, there have been many clinical trials to treat cancers through systemic blocking of autophagy. Such systemic inhibition affects both tumor cells and non-tumor cells, and the consequence of blocked autophagy in non-tumor cells in the context of tumor microenvironment is relatively understudied. Here, we examined the effect of autophagy-deficient myeloid cells on the progression of autophagy-competent tumors. We found that blocking autophagy only in myeloid cells modulated tumor progression markedly but such effects were context dependent. In a tumor implantation model, the growth of implanted tumor cells was substantially reduced in mice with autophagy-deficient myeloid cells; T cells infiltrated deeper into the tumors and were responsible for the reduced growth of the implanted tumor cells. In an oncogene-driven tumor induction model, however, tumors grew faster and metastasized more in mice with autophagy-deficient myeloid cells. These data demonstrate that the autophagy status of myeloid cells plays a critical role in tumor progression, promoting or suppressing tumor growth depending on the context of tumor-myeloid cell interactions. This study indicates that systemic use of autophagy inhibitors in cancer therapy may have differential effects on rates of tumor progression in patients due to effects on myeloid cells and that this warrants more targeted use of selective autophagy inhibitors in a cancer therapy in a clinical setting.

Targeting the pancreatic tumor microenvironment by plant-derived products and their nanoformulations.

Pancreatic cancer remains a significant health issue with limited treatment options. The tumor stroma, a complex environment made up of different cells and proteins, plays a crucial role in tumor growth and chemoresistance. Targeting tumor stroma, consisting of diverse non-tumor cells such as fibroblasts, extracellular matrix (ECM), immune cells, and also pre-vascular cells is encouraging for remodeling solid cancers, such as pancreatic cancer. Remodeling the stroma of pancreas tumors can be suggested as a strategy for reducing resistance to chemo/immunotherapy. Several studies have shown that phytochemicals from plants can affect the tumor environment and have anti-cancer properties. By targeting key pathways involved in stromal activation, phytochemicals may disrupt communication between the tumor and stroma and make tumor cells more sensitive to different treatments. Additionally, phytochemicals have immunomodulatory and anti-angiogenic properties, all of which contribute to their potential in treating pancreatic cancer. This review will provide a detailed look at how phytochemicals impact the tumor stroma and their effects on pancreatic tumor growth, spread, and response to treatment. It will also explore the potential of combining phytochemicals with other treatment options like chemotherapy, immunotherapy, and radiation.

Extended Synaptotagmins 1 and 2 Are Required for Store-Operated Calcium Entry, Cell Migration and Viability in Breast Cancer Cells.

Extended synaptotagmins (E-Syts) are endoplasmic reticulum (ER)-associated proteins that facilitate the tethering of the ER to the plasma membrane (PM), participating in lipid transfer between the membranes and supporting the Orai1-STIM1 interaction at ER-PM junctions. Orai1 and STIM1 are the core proteins of store-operated Ca2+ entry (SOCE), a major mechanism for Ca2+ influx that regulates a variety of cellular functions. Aberrant modulation of SOCE in cells from different types of cancer has been reported to underlie the development of several tumoral features. Here we show that estrogen receptor-positive (ER+) breast cancer MCF7 and T47D cells and triple-negative breast cancer (TNBC) MDA-MB-231 cells overexpress E-Syt1 and E-Syt2 at the protein level; the latter is also overexpressed in the TNBC BT20 cell line. E-Syt1 and E-Syt2 knockdown was without effect on SOCE in non-tumoral MCF10A breast epithelial cells and ER+ T47D breast cancer cells; however, SOCE was significantly attenuated in ER+ MCF7 cells and TNBC MDA-MB-231 and BT20 cells upon transfection with siRNA E-Syt1 or E-Syt2. Consistent with this, E-Syt1 and E-Syt2 knockdown significantly reduced cell migration and viability in ER+ MCF7 cells and the TNBC cells investigated. To summarize, E-Syt1 and E-Syt2 play a relevant functional role in breast cancer cells.