Combination Cancer Therapy Research Articles

Metal–Organic Framework-Capped Gold Nanorod Hybrids for Combinatorial Cancer Therapy

Recently, nanomaterials have attracted extensive attention in cancer-targeting therapy and as drug delivery vehicles owing to their unique surface and size properties. Multifunctional combinations of nanomaterials have become a research hotspot as researchers aim to provide a full understanding of their nanomaterial characteristics. In this study, metal–organic framework-capped gold nanorod hybrids were synthesized. Our research explored their ability to kill tumor cells by locally increasing the temperature via photothermal conclusion. The specific peroxidase-like activity endows the hybrids with the ability to disrupt the oxidative balance in vitro. Simultaneously, chemotherapeutic drugs are administered and delivered by loading and transportation for effective combinatorial cancer treatment, thereby enhancing the curative effect and reducing the unpredictable toxicity and side effects of large doses of chemotherapeutic drugs. These studies can improve combinatorial cancer therapy and enhance cancer treatment.

Abstract B011: Predictable successes: drug additivity explains the efficacy of combination therapies for metastatic urothelial cancer

Abstract Objective: Combination drug regimens have changed the treatment landscape of metastatic urothelial cancer (mUC) and other cancers and are integrated into routine clinical practice. Combination drug regimens may impact cancer outcomes via three major pharmacologic principles: less-than-additive, additive, or more-than-additive efficacy (i.e., synergy). Despite the profound implications of these types of interactions on future drug and biomarker development, as well as on treatment sequencing, these principles have been underexplored in contemporary clinical trials. Here we analyze recent phase 3 trials in locally advanced or metastatic UC to assess whether progression-free survival (PFS) distributions of combination therapies with immune checkpoint inhibitors (ICIs) are lesser than, greater than, or equal to the additive effect expected based on single-agent efficacies. Methods: We analyzed phase 3 trials in locally advanced or metastatic UC including EV302, CheckMate 901, KEYNOTE-361, DANUBE, and IMvigor130. When one monotherapy was not included as an arm in the phase 3 trial, we utilized monotherapy PFS distributions from trials in patients with metastatic UC including EV103, KEYNOTE-045, CheckMate 275, and HCRN-GU17-294. The expected additive effect of a drug combination was calculated by adding the PFS durations of individual drugs, sampled from monotherapy distributions, as recently described for other approved oncology drug combinations (Hwangbo et al, Nature Cancer, 2023). Results: Combination therapies with ICIs were as clinically effective as predicted by additivity, or less so in one case. Specifically, Pembrolizumab plus Enfortumab vedotin (EV302), Nivolumab plus Gemcitabine/Cisplatin (CheckMate 901), Pembrolizumab plus chemotherapy (KEYNOTE-361), and Durvalumab plus Tremelimumab (DANUBE) each exhibited PFS distributions that were statistically indistinguishable from PFS predicted by the additivity model (Cox Proportional Hazards). Atezolizumab plus chemotherapy (IMvigor130) was inferior to additivity. Subgroup analyses by PD-L1 expression and by cisplatin versus carboplatin will be presented. Conclusions: Life-prolonging treatments for mUC have been the result of additive combination therapies, wherein the efficacy of the drug combination is quantitatively explained by the individual efficacies of the component drugs. Additivity in this setting has several potential implications: (1) when a single-agent is principally active in a biomarker-defined subpopulation, the use of that agent in a combination will also principally improve outcomes in that subpopulation; (2) net duration of disease control may be similar between up-front combination and sequential use of the same drugs; assuming that the biology of disease at progression does not preclude the ability to receive subsequent lines of therapy, and (3) future drug development should prioritize combinations based on highly active single agents rather than solely based on hypothesized mechanistic rationale. Citation Format: Noah M. Schlachter, Eric J. Miller, Jonathan F. Anker, Matthew D. Galsky, Adam C. Palmer. Predictable successes: drug additivity explains the efficacy of combination therapies for metastatic urothelial cancer [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2024 May 17-20; Charlotte, NC. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(10_Suppl):Abstract nr B011.

Reinforcing Carrier‐Free Photothermal Nanodrugs Through Flavonol‐Driven Assembly

AbstractCarrier‐free nanodrugs that integrate chemodrugs and other therapeutic agents demonstrate good efficacy and minimized side effects, showing promise for combined therapy. However, a key challenge lies in enhancing the bioavailability and therapeutic potential of the nanodrugs through a controllable assembly process. Herein, a carrier‐free photothermal nanodrug (ZPQ NPs) is constructed through flavonol‐driven assembly with amine‐substituted perylene diimide for enhanced chemo‐photothermal combined cancer therapy. The flavonol, particularly quercetin, facilitates J‐aggregation of perylene diimide derivatives within the nanodrug and contributes to multiple improvements, including red‐shifted absorption, enhanced fluorescence intensity, improved photothermal conversion efficiency as well as excellent photostability. Moreover, the nanodrug also demonstrates enhanced cellular uptake and intracellular reactive oxygen species scavenging capability. The combination of quercetin and photothermal effect effectively kills cancer cells, as well as alleviates inflammation following photothermal therapy. Guided by in vivo fluorescence imaging, the application of ZPQ NPs results in complete tumor elimination and effectively inhibits tumor recurrence through chemo‐photothermal combined therapy. This work presents a straightforward strategy for constructing carrier‐free nanodrugs that exhibit simultaneous enhancements in both photophysical properties and biological activity.

Cascade loop of ferroptosis induction and immunotherapy based on metal‐phenolic networks for combined therapy of colorectal cancer

AbstractCancer immunotherapy is the most promising method for tumor therapy, while ferroptosis could activate the immunogenicity of cancer and strengthen the cellular immune response. However, limited by the complex tumor microenvironment, the abundant glutathione (GSH) and low reactive oxygen species (ROS) seriously weaken ferroptosis and the immune response. Herein, the authors report photothermal metal‐phenolic networks (MPNs) supplied with buthionine sulfoximine (BSO) by reducing levels of GSH and then trapping the tumor cells in the ferroptosis and immunotherapy cascade loop to eliminate colorectal cancer (CRC). The MPNs coated with the model antigen ovalbumin can accumulate at the tumor site, mediate immunogenic cell death (ICD) under NIR irradiation, and initiate tumoricidal immunity. Then the activated CD8+ T cells would release IFN‐γ to inhibit GPX4 and promote the immunogenic ferroptosis induced by Fe3+ and BSO. Finally, the tumor cells at intertumoral and intratumoral levels would be involved in the ferroptosis‐dominated cancer‐immunity circle for CRC eradication, resulting in outstanding therapeutic outcomes in both primary and distant tumor models. Overall, this strategy employs a photothermal nanoplatform to rapidly stimulate ICD and restrain the oxidation defense system, which provides a promising approach to significantly amplify the “cascade loop” of ferroptosis induction and immunotherapy for treatment of CRC.

Biogated mesoporous silica nanoagents for inhibition of cell migration and combined cancer therapy.

Migration is an initial step in tumor expansion and metastasis; suppressing cellular migration is beneficial to cancer therapy. Herein, we designed a novel biogated nanoagents that integrated the migration inhibitory factor into the mesoporous silica nanoparticle (MSN) drug delivery nanosystem to realize cell migratory inhibition and synergistic treatment. Antisense oligonucleotides (Anti) of microRNA-330-3p, which is positively related with cancer cell proliferation, migration, invasion, and angiogenesis, not only acted as the locker for blocking drugs but also acted as the inhibitory factor for suppressing migration via gene therapy. Synergistic with gene therapy, the biogated nanoagents (termed as MSNs-Gef-Anti) could achieve on-demand drug release based on the intracellular stimulus-recognition and effectively kill tumor cells. Experimental results synchronously demonstrated that the migration suppression ability of MSNs-Gef-Anti nanoagents (nearly 30%) significantly contributed to cancer therapy, and the lethality rate of the non-small-cell lung cancer was up to 70%. This strategy opens avenues for realizing efficacious cancer therapy and should provide an innovative way for pursuing the rational design of advanced nano-therapeutic platforms with the combination of cancer cell migratory inhibition.

HER2 siRNA Facilitated Gene Silencing Coupled with Doxorubicin Delivery: A Dual Responsive Nanoplatform Abrogates Breast Cancer.

The present study investigated the concurrent delivery of antineoplastic drug, doxorubicin, and HER2 siRNA through a targeted theranostic metallic gold nanoparticle designed using polysaccharide, PSP001. The as-synthesized HsiRNA@PGD NPs were characterized in terms of structural, functional, physicochemical, and biological properties. HsiRNA@PGD NPs exposed adequate hydrodynamic size, considerable ζ potential, and excellent drug/siRNA loading and encapsulation efficiency. Meticulous exploration of the biocompatible dual-targeted nanoconjugate exhibited an appealing biocompatibility and pH-sensitive cargo release kinetics, indicating its safety for use in clinics. HsiRNA@PGD NPs deciphered competent cancer cell internalization, enhanced cytotoxicity mediated via the induction of apoptosis, and excellent downregulation of the overexpressing target HER2 gene. Further in vivo explorations in the SKBR3 xenograft breast tumor model revealed the appealing tumor reduction properties, selective accumulation in the tumor site followed by significant suppression of the HER2 gene which contributed to the exclusive abrogation of breast tumor mass by the HsiRNA@PGD NPs. Compared to free drugs or the monotherapy constructs, the dual delivery approach produced a synergistic suppression of breast tumors both in vitro and in vivo. Hence the drawings from these findings implicate that the as-synthesized HsiRNA@PGD NPs could offer a promising platform for chemo-RNAi combinational breast cancer therapy.

Effective delivery of anti-PD-L1 siRNA with human heavy chain ferritin (HFn) in acute myeloid leukemia cell lines.

Because of the high biocompatibility, self-assembly capability, and CD71-mediated endocytosis, using human heavy chain ferritin (HFn) as a nanocarrier would greatly increase therapeutic effectiveness and reduce possible adverse events. Anti-PD-L1 siRNA can downregulate the level of PD-L1 on tumor cells, resulting in the activation of effector T cells against leukemia. Therefore, this study aimed to produce the tumor-targeting siPD-L1/HFn nanocarrier. Briefly, the HFn coding sequence was cloned into a pET-28a, and the constructed expression plasmid was subsequently transformed into E. coli BL21. After induction of Isopropyl β-D-1-thiogalactopyranoside (IPTG), HFn was purified with Ni-affinity chromatography and dialyzed against PBS. The protein characteristics were analyzed using SDS-PAGE, Western Blot, and Dynamic light scattering (DLS). The final concentration was assessed using the Bicinchoninic acid (BCA) assay. The encapsulation was performed using the standard pH system. The treatment effects of siPD-L1/HFn were carried out on HL-60 and K-562 cancer cell lines. The RT-PCR was used to determine the mRNA expression of PD-L1. The biocompatibility and excretion of siPD-L1/HFn have also been evaluated. The expression and purity of HFn were well verified through SDS-PAGE, WB, and DLS. RT-PCR analyses also showed significant siRNA-mediated PD-L1 silencing in both HL-60 and K-562 cells. Our study suggested a promising approach for siRNA delivery. This efficient delivery system can pave the way for the co-delivery of siRNAs and multiple chemotherapies to address the emerging needs of cancer combination therapy.

Tween 80 Micelles Loaded with Fe3O4 Nanoparticles and Artemisinin for Combined Oxygen-Independent Ferroptosis Therapy of Cancer.

Artemisinin has an endoperoxide bridge structure, which can be cleaved by ferrous ions to generate various carbonyl radicals in an oxygen-independent manner, highlighting its potential for treating hypoxic tumors. In our study, we fabricated Tween 80 micelles loaded with Fe3O4 nanoparticles and artemisinin for cancer therapy. The synthesized Fe3O4 nanoparticles and drug-loaded micelles have particle sizes of about 5 nm and 80 nm, respectively, both exhibiting excellent dispersibility and stability. After uptake by MCF-7 cells, drug-loaded micelles release Fe2+ and ART into the cytoplasm, effectively inducing the generation of reactive oxygen species (ROS) in hypoxic conditions, thereby enhancing toxicity against cancer cells. In vitro and in vivo studies have demonstrated that ART and Fe3O4 nanoparticles are encapsulated in Tween 80 to form micelles, which effectively prevent premature release during circulation in the body. Although free ART and Fe3O4 nanoparticles can inhibit tumor growth, TW80-Fe3O4-ART micelles demonstrate a more pronounced inhibitory effect, with a tumor suppression rate of up to 85%. A novel strategy based on artemisinin and ferroptosis is thus offered, holding a favorable prospect for hypoxic cancer therapy.

Biocompatible Copper-Based Nanocomposites for Combined Cancer Therapy.

Copper (Cu) and Cu-based nanomaterials have received tremendous attention in recent years because of their unique physicochemical properties and good biocompatibility in the treatment of various diseases, especially cancer. To date, researchers have designed and fabricated a variety of integrated Cu-based nanocomplexes with distinctive nanostructures and applied them in cancer therapy, mainly including chemotherapy, radiotherapy (RT), photothermal therapy (PTT), chemodynamic therapy (CDT), photodynamic therapy (PDT), cuproptosis-mediated therapy, etc. Due to the limited effect of a single treatment method, the development of composite diagnostic nanosystems that integrate chemotherapy, PTT, CDT, PDT, and other treatments is of great significance and offers great potential for the development of the next generation of anticancer nanomedicines. In view of the rapid development of Cu-based nanocomplexes in the field of cancer therapy, this review focuses on the current state of research on Cu-based nanomaterials, followed by a discussion of Cu-based nanocomplexes for combined cancer therapy. Moreover, the current challenges and future prospects of Cu-based nanocomplexes in clinical translation are proposed to provide some insights into the design of integrated Cu-based nanotherapeutic platforms.

Protease-activated receptor 2: a promising therapeutic target for women's cancers.

Cancers affecting women, such as breast, uterine, ovarian, endometrial and cervical cancers, have become increasingly prevalent. The growing incidence and death rates associated with these cancers warrant the development of innovative and alternative approaches to current treatments. This article investigates the association of women's cancers with a molecular target known as protease-activated receptor 2 (PAR2), a G-protein coupled receptor that is expressed on the surface of cancer cells. Expression levels of the PAR2 gene were curated from publicly available databases and were found to be significantly overexpressed in tissues from patients with breast, uterine, ovarian, endometrial or cervical cancer compared to normal tissues. PAR2 overexpression has been previously linked to tumor progression and, in some cases, tumor growth. Activation of PAR2 by either endogenous proteases or synthetic agonists triggers certain downstream intracellular signaling pathways that have been associated with tumor progression, cell migration and invasion, angiogenesis and apoptosis of cancer cells. While recent advances have led to the identification of several PAR2 antagonists, none has yet been developed for human use. Additionally, PAR2 inhibition has been shown also to increase the efficacy of chemotherapeutic drugs, allowing them to be potentially used at less toxic doses in combination therapies for cancer. The present work briefly summarizes the current status of PAR2 as a potential therapeutic target for treating women's cancers. Significance Statement This article highlights potential roles for PAR2 in cancers affecting women. Overexpression of the PAR2 gene in women's cancers is associated with various oncogenic processes such as tumor progression, cell migration and invasion, ultimately contributing to poorer patient prognoses. Given the increasing incidence of women's cancers, there is an urgent need to develop novel therapeutic drugs and PAR2 represents a promising target for developing new treatments.

Electrospun medicated gelatin/polycaprolactone Janus fibers for photothermal-chem combined therapy of liver cancer

Liver cancer is a common cancer in the world, and core-shell nanoparticles as a commonly used combination therapy for local tumor ablation, have many shortcomings. In this study, photothermal Janus nanofibers were prepared using a electrospinning technology for tumor treatment, and the products were characterized and in vitro photothermal performance investigated. The micromorphology analysis showed that the photothermic agent CuS and electrospun fibers (loaded with CuS and anticancer drug dihydromyricetin) were successfully prepared, with diameters of 11.58 ± 0.27 μm and 1.19 ± 0.01 μm, respectively. Water contact angle and tensile test indicated that the fiber membranes has a certain hydrophilic adhesion and excellent mechanical strength. The fiber membranes has 808 nm near-infrared laser photothermal heating performance and photothermal stability, and it also has a strong response to the laser that penetrates biological tissue. In addition, in vitro cell culture and in vivo implantation study showed that the fiber membranes could kill HepG2 hepatocellular carcinoma cells combined with photothermal-chem and could be enriched in the implantation area, respectively. Hence, the Janus membranes may be a potential cancer treatment material.

Fabrication of Rhenium Disulfide/Mesoporous Silica Core-Shell Nanoparticles for a pH-Responsive Drug Release and Combined Chemo-Photothermal Therapy.

A stimuli-responsive drug delivery nanocarrier with a core-shell structure combining photothermal therapy and chemotherapy for killing cancer cells was constructed in this study. The multifunctional nanocarrier ReS2@mSiO2-RhB entails an ReS2 hierarchical nanosphere coated with a fluorescent mesoporous silica shell. The three-dimensional hierarchical ReS2 nanostructure is capable of effectively absorbing near-infrared (NIR) light and converting it into heat. These ReS2 nanospheres were generated by a hydrothermal synthesis process leading to the self-assembly of few-layered ReS2 nanosheets. The mesoporous silica shell was further coated on the surface of the ReS2 nanospheres through a surfactant-templating sol-gel approach to provide accessible mesopores for drug uploading. A fluorescent dye (Rhodamine B) was covalently attached to silica precursors and incorporated during synthesis in the mesoporous silica walls toward conferring imaging capability to the nanocarrier. Doxorubicin (DOX), a known cancer drug, was used in a proof-of-concept study to assess the material's ability to function as a drug delivery carrier. While the silica pores are not capped, the drug molecule loading and release take advantage of the pH-governed electrostatic interactions between the drug and silica wall. The ReS2@mSiO2-RhB enabled a drug loading content as high as 19.83 mg/g doxorubicin. The ReS2@mSiO2-RhB-DOX nanocarrier's cumulative drug release rate at pH values that simulate physiological conditions showed significant pH responsiveness, reaching 59.8% at pH 6.8 and 98.5% and pH 5.5. The in vitro testing using HeLa cervical cancer cells proved that ReS2@mSiO2-RhB-DOX has a strong cancer eradication ability upon irradiation with an NIR laser owing to the combined drug delivery and photothermal effect. The results highlight the potential of ReS2@mSiO2-RhB nanoparticles for combined cancer therapy in the future.

Ti3C2Tx MXene nanosheet-based drug delivery/cascaded enzyme system for combination cancer therapy and anti-inflammation

Photothermal therapy (PTT)-based combination therapy is an effective approach to cancer treatment. However, there is a possibility of tumor development due to the inflammation caused by PTT. In addition, hyperthermia can cause damage to normal tissues. This work reported a drug delivery/cascade enzyme system based on Ti3C2Tx MXene nanosheets. Ultra-small, degradable mesoporous silica nanoparticles (DS-MSN) were prepared to load phloretin (Phl), which has anti-inflammatory, antioxidant, and anticancer properties. Subsequently, glucose oxidase (GOx) was adsorbed on the surface of DS-MSN. The nanoparticles were then modified on Ti3C2Tx MXene nanosheets and finally treated with polyethylene glycol (PEG) to obtain the multifunctional system named Ti3C2Tx-Phl@DS-MSN-GOx-PEG (TPDMGP). The high near-infrared photothermal conversion efficiency of Ti3C2Tx made it suitable for PTT. GOx and Ti3C2Tx formed a cascade enzyme system inside cancer cells: Ti3C2Tx exhibited catalase (CAT)-like activity that decomposed intracellular hydrogen peroxide (H2O2) into O2, which was provided to GOx for enhanced starvation therapy. GOx in the presence of O2 produces H2O2, for the oxygen production of Ti3C2Tx. Meanwhile, DS-MSN could be degraded in the reducing environment inside cancer cells as it contains disulfide bonds in its backbone, thus releasing Phl for chemotherapy. Such a combination therapy strategy could achieve a satisfactory therapeutic outcome by low-temperature PTT while evading normal tissue damage by high temperature. The anti-inflammatory effects of both Ti3C2Tx and Phl enabled TPDMGP to eliminate the inflammation caused by PTT via the scavenging of reactive oxygen species (ROS). The multifunctional system is expected to generate new paradigms for cancer PTT.

Von Hippel-Lindau protein signalling in clear cell renal cell carcinoma.

The distinct pathological and molecular features of kidney cancer in adaptation to oxygen homeostasis render this malignancy an attractive model for investigating hypoxia signalling and potentially developing potent targeted therapies. Hypoxia signalling has a pivotal role in kidney cancer, particularly within the most prevalent subtype, known as renal cell carcinoma (RCC). Hypoxia promotes various crucial pathological processes, such as hypoxia-inducible factor (HIF) activation, angiogenesis, proliferation, metabolic reprogramming and drug resistance, all of which contribute to kidney cancer development, growth or metastasis formation. A substantial portion of kidney cancers, in particular clear cell RCC(ccRCC), are characterized by a loss of function of Von Hippel-Lindautumour suppressor (VHL), leading to the accumulation of HIF proteins, especially HIF2α, a crucial driver of ccRCC. Thus, therapeutic strategies targeting pVHL-HIF signalling have been explored in ccRCC, culminating in the successful development of HIF2α-specific antagonists such as belzutifan (PT2977), an FDA-approved drug to treat VHL-associated diseases including advanced-stage ccRCC. An increased understanding of hypoxia signalling in kidney cancer came from the discovery of novel VHL protein (pVHL) targets, and mechanisms of synthetic lethality with VHL mutations. These breakthroughs can pave the way for the development of innovative and potent combination therapies in kidney cancer.

Nanoparticle-enhanced PD-1/PD-L1 targeted combination therapy for triple negative breast cancer.

Breast cancer with triple-negative subtype (TNBC) presents significant challenges with limited treatment options and a poorer prognosis than others. While PD-1/PD-L1 checkpoint inhibitors have shown promise, their efficacy in TNBC remains constrained. In recent years, nanoparticle (NP) technologies offer a novel approach to enhance cancer therapy by optimizing the tumor microenvironment and augmenting chemo- and immunotherapy effects in various preclinical and clinical settings. This review discusses recent investigations in NP strategies for improving PD-1/PD-L1 blockade-based combination therapy for TNBC. Those include single or multi-therapeutic NPs designed to enhance immunogenicity of the tumor, induce immunogenic cell death, and target immunosuppressive elements within the tumor microenvironment. The investigations also include NPs co-loaded with PD-L1 inhibitors and other therapeutic agents, leveraging targeted delivery and synergistic effects to maximize efficacy while minimizing systemic toxicity. Overall, NP approaches represent a promising avenue for enhancing PD-1/PD-L1 checkpoint blockade-based combination therapy in TNBC and encourage further developmental studies.

Exploration of the photothermal role of curcumin-loaded targeted carbon nanotubes as a potential therapy for melanoma cancer

In this research, the hydrophilic structure of multi-walled carbon nanotubes (MWCNTs) was modified by synthesizing polycitric acid (PCA) and attaching folic acid (FA) to create MWCNT–PCA–FA. This modified nanocomplex was utilized as a carrier for the lipophilic compound curcumin (Cur). Characterization techniques including TGA, TEM, and UV–visible spectrophotometry were used to analyze the nanocomplex. The mechanism of cancer cell death induced by MWCNT–PCA–FA was studied extensively using the MTT assay, colony formation analysis, cell cycle assessment via flow cytometry, and apoptosis studies. Furthermore, we assessed the antitumor efficacy of these targeted nanocomplexes following exposure to laser radiation. The results showed that the nanocomposites and free Cur had significant toxicity on melanoma cancer cells (B16F10 cells) while having minimal impact on normal cells (NHDF cells). This selectivity for cancerous cells demonstrates the potential of these compounds as therapeutic agents. Furthermore, MWCNT–PCA–FA/Cur showed superior cytotoxicity compared to free Cur alone. Colony formation studies confirmed these results. The researchers found that MWCNT–FA–PCA/Cur effectively induced programmed cell death. In photothermal analysis, MWCNT–PCA–FA/Cur combined with laser treatment achieved the highest mortality rate. These promising results suggest that this multifunctional therapeutic nanoplatform holds the potential for combination cancer therapies that utilize various established therapeutic methods.

Opposing Interplay between Nuclear Factor Erythroid 2-Related Factor 2 and Forkhead BoxO 1/3 is Responsible for Sepantronium Bromide's Poor Efficacy and Resistance in Cancer cells: Opportunity for Combination Therapy in Triple Negative Breast Cancer.

Survivin, a cancer-cell-specific multifunctional protein, is regulated by many oncogenic signaling pathways and an effective therapeutic target. Although, several types of survivin-targeting agents have been developed over the past few decades, none of them received clinical approval. This could be because survivin expression is tightly controlled by the feedback interaction between different signaling molecules. Of the several signaling pathways that are known to regulate survivin expression, the phosphatidylinositol 3-kinase/AKT serine-threonine kinase/forkhead boxO (PI3K/AKT/FoxO) pathway is well-known for feedback loops constructed by cross-talk among different molecules. Using sepantronium bromide (YM155), the first of its class of survivin-suppressant, we uncovered the existence of an interesting cross-talk between Nuclear Factor Erythroid 2-Related Factor 2 (NRF2) and FoxO transcription factors that also contributes to YM155 resistance in triple negative breast cancer (TNBC) cells. Pharmacological manipulation to interrupt this interaction not only helped restore/enhance the drug-sensitivity but also prompted effective immune clearance of cancer cells. Because the YM155-induced reactive oxygen species (ROS) initiates this feedback, we believe that it will be occurring for many ROS-producing chemotherapeutic agents. Our work provides a rational explanation for the poor efficacy of YM155 compared to standard chemotherapy in clinical trials. Finally, the triple drug combination approach used herein might help reintroducing YM155 into the clinical pipeline, and given the high survivin expression in TNBC cells in general, it could be effective in treating this subtype of breast cancer.

The real-world data of immune-checkpoint inhibitor combination therapy for unresectable or metastatic esophageal cancer: a multi-institutional cohort study.

The real-world efficacy, feasibility, and prognostic factors of immune-checkpoint inhibitor combination therapy for unresectable or metastatic esophageal cancer are not fully established. This multi-institutional retrospective cohort study evaluated 71 consecutive patients treated with immune-checkpoint inhibitor combination therapy for esophageal cancer between March 2021 and December 2022. We assessed tumor response, safety, and long-term survival. In patients with measurable lesions, the response rate was 58%, and the disease control rate for all enrolled patients was 80%. Five patients (7.0%) underwent successful conversion surgery. Grade 3 or higher immune-related adverse events occurred in 13% of patients, and one patient (1.4%) died due to cholangitis. Median progression-free survival was 9.7 (95% confidence interval: 6.5-not reached). C-reactive protein levels and performance status were identified as significant predictors of progression-free survival through Cox proportional hazards analysis. Immune-checkpoint inhibitor combination therapy for esophageal cancer demonstrated comparable tumor response, safety, and long-term survival to previous randomized clinical trials. Patients with good performance status and low C-reactive protein levels may be suitable candidates for this treatment.

BET inhibition induces GDH1-dependent glutamine metabolic remodeling and vulnerability in liver cancer

Abstract Bromodomain and extra-terminal domain (BET) proteins, which function partly through MYC proto-oncogene (MYC), are critical epigenetic readers and emerging therapeutic targets in cancer. Whether and how BET inhibition simultaneously induces metabolic remodeling in cancer cells remains unclear. Here we find that even transient BET inhibition by JQ-1 and other pan-BET inhibitors (pan-BETis) blunts liver cancer cell proliferation and tumor growth. BET inhibition decreases glycolytic gene expression but enhances mitochondrial glucose and glutamine oxidative metabolism revealed by metabolomics and isotope labeling analysis. Specifically, BET inhibition downregulates miR-30a to upregulate glutamate dehydrogenase 1 (GDH1) independent of MYC, which produces α-ketoglutarate for mitochondrial oxidative phosphorylation (OXPHOS). Targeting GDH1 or OXPHOS is synthetic lethal to BET inhibition, and combined BET and OXPHOS inhibition therapeutically prevents liver tumor growth in vitro and in vivo. Together, we uncover an important epigenetic-metabolic crosstalk whereby BET inhibition induces MYC-independent and GDH1-dependent glutamine metabolic remodeling that can be exploited for innovative combination therapy of liver cancer.

Reactive Oxygen Species-Activated Self-Accelerated Drug Release Nanoparticles for Enhanced Cancer Combination Therapy

Reactive Oxygen Species-Activated Self-Accelerated Drug Release Nanoparticles for Enhanced Cancer Combination Therapy