BACKGROUND:Colorectal cancer (CRC) incidence is increasing in recent years due to intestinal flora imbalance, making oral probiotics a hotspot for research. However, numerous studies related to intestinal flora regulation ignore its internal mechanisms without in-depth research.RESULTS:Here, we developed a probiotic microgel delivery system (L.r@(SA-CS)2) through the layer-by-layer encapsulation technology of alginate (SA) and chitosan (CS) to improve gut microbiota dysbiosis and enhance anti-tumor therapeutic effect. Short chain fatty acids (SCFAs) produced by L.r have direct anti-tumor effects. Additionally, it reduces harmful bacteria such as Proteobacteria and Fusobacteriota, and through bacteria mutualophy increases beneficial bacteria such as Bacteroidota and Firmicutes which produce butyric acid. By binding to the G protein-coupled receptor 109A (GPR109A) on the surface of colonic epithelial cells, butyric acid can induce apoptosis in abnormal cells. Due to the low expression of GPR109A in colon cancer cells, MK-6892 (MK) can be used to stimulate GPR109A. With increased production of butyrate, activated GPR109A is able to bind more butyrate, which further promotes apoptosis of cancer cells and triggers an antitumor response.CONCLUSION:It appears that the oral administration of L.r@(SA-CS)2 microgels may provide a treatment option for CRC by modifying the gut microbiota.
Transforming growth factor β (TGF-β), a versatile immunosuppressive cytokine, has gained increasing attention as a potential target for cancer immunotherapy. However, current strategies are constrained by tumor heterogeneity and drug resistance. Therapeutic probiotics, such as Escherichia coli Nissle1917 (EcN), not only regulate the gut microbiota to increase beneficial bacteria with anti-tumor effects, but also modulate immune factors within the body, thereby enhancing immunity. In this study, we developed an oral microgel delivery system of EcN@(CS-SA)2 by electrostatic interaction between chitosan (CS) and sodium alginate (SA), aiming to enhance its bioavailability in the gastrointestinal tract (GIT). Notably, EcN@(CS-SA)2 microgel showed a synergistic enhancement of the anti-tumor efficacy of Galunisertib (Gal, a TGF-β inhibitor) by inducing apoptosis and immunogenic cell death (ICD) in tumor cells, as well as promoting increased infiltration of CD8+ T cells into the tumor microenvironment (TME).
Vascular endothelial growth factor inhibitors, including tyrosine kinase inhibitors (TKIs), possess immunomodulatory properties and have shown promising outcomes when combined with anti-PD-1 antibodies. The OASIS phase II trial (NCT04503967) is designed to determine the clinical activity and safety of nivolumab (anti-PD-1) and anlotinib hydrochloride (a multi-targets TKI) as second-line or above therapy in patients with advanced gastric adenocarcinoma (GAC) and esophageal squamous cell carcinoma (ESCC). From December 2020 to September 2022, 45 patients with GAC and 3 with ESCC were enrolled in this study. The pre-specified endpoints were reached, with the primary endpoint of overall response rate achieving 29.2%. For secondary objectives, disease control rate was 64.6%; median progression-free survival was 4.0 months; and median overall survival was 11.1 months with a manageable toxicity profile. The exploratory analyses unveiled that the balance of gut bacteria and the presence of a pre-existing immune signature characterized by a high percentage of CD68+PD-L1+ PD-1+ macrophages and low pretreatment variant allele frequencies (VAF), as well as low expression of certain cytokines were significantly associated with improved clinical outcomes in patients with GAC. Anlotinib hydrochloride is a multi-target tyrosine kinase receptor inhibitor, previously combined with anti-PD1 as therapeutic strategy for several cancer types. Here the authors report the results of a phase II trial of nivolumab (anti-PD1) plus anlotinib hydrochloride in patients with advanced gastric adenocarcinoma and esophageal squamous cell carcinoma.
Bacteria-mediated antitumor therapy has gained widespread attention for its innate tumor-targeting capability and excellent immune activation properties. Nevertheless, the clinical approval of bacterial therapies remains elusive primarily due to the formidable challenge of balancing safety with enhancing in vivo efficacy. In this study, leveraging the probiotic Escherichia coli Nissle1917 (EcN) emerges as a promising approach for colon cancer therapy, offering a high level of safety attributed to its lack of virulence factors and its tumor-targeting potential owing to its obligate anaerobic nature. Specifically, we delineate the erythrocyte (RBC) membrane-camouflaged EcN, termed as Trojan horse EcN@RBC, which triggers apoptosis in tumor cells by mitigating mitochondrial membrane potential (MMP) and subsequently activating the PINK1/Parkin pathway associated with mitophagy. Concurrently, the decline in MMP induced by mitophagy disrupts the mitochondrial permeability transition pore (MPTP), leading to the release of Cytochrome C and subsequent apoptosis induction. Moreover, synergistic effects were observed through the combination of the autophagy activator rapamycin, bolstering the antitumor efficacy in vivo. These findings offer novel insights into probiotic-mediated antitumor mechanisms and underscore the therapeutic potential of EcN@RBC for colon cancer patients.
The high nutrient and energy demand of tumor cells compared to normal cells to sustain rapid proliferation offer a potentially auspicious avenue for implementing starvation therapy. However, conventional starvation therapy, such as glucose exhaustion and vascular thrombosis, can lead to systemic toxicity and exacerbate tumor hypoxia. Herein, we developed a new “valve-off” starvation tactic, which was accomplished by closing the valve of glucose transporter protein 1 (GLUT1). Specifically, dihydroartemisinin (DHA), 2,20-azobis [2-(2-imidazolin-2-yl) propane] dihydrochloride (AI), and Ink were co-encapsulated in a sodium alginate (ALG) hydrogel. Upon irradiation with the 1064 nm laser, AI rapidly disintegrated into alkyl radicals (R•), which exacerbated the DHA-induced mitochondrial damage through the generation of reactive oxygen species and further reduced the synthesis of adenosine triphosphate (ATP). Simultaneously, the production of R• facilitated DHA-induced starvation therapy by suppressing GLUT1, which in turn reduced glucose uptake. Systematic in vivo and in vitro results suggested that this radical-enhanced “valve-off” strategy for inducing tumor cell starvation was effective in reducing glucose uptake and ATP levels. This integrated strategy induces tumor starvation with efficient tumor suppression, creating a new avenue for controlled, precise, and concerted tumor therapy.
Targeted therapy and immunotherapy have brought hopes for precision cancer treatment. However, complex physiological barriers and tumor immunosuppression result in poor efficacy, side effects, and resistance to antitumor therapies. Bacteria-mediated antitumor therapy provides new options to address these challenges. Thanks to their special characteristics, bacteria have excellent ability to destroy tumor cells from the inside and induce innate and adaptive antitumor immune responses. Furthermore, bacterial components, including bacterial vesicles, spores, toxins, metabolites, and other active substances, similarly inherit their unique targeting properties and antitumor capabilities. Bacteria and their accessory products can even be reprogrammed to produce and deliver antitumor agents according to clinical needs. This review first discusses the role of different bacteria in the development of tumorigenesis and the latest advances in bacteria-based delivery platforms and the existing obstacles for application. Moreover, the prospect and challenges of clinical transformation of engineered bacteria are also summarized.
Epigenetic alteration is a key feature that contributes to the progression of bladder cancer (BC) and long non-coding RNAs serve crucial role in the epigenetic modulation. This study was designed to explore the epigenetic regulation of LINC00592 in BC. LINC00592 expression in BC was examined. Then, LINC00592 was silenced in BC cell followed by cell behavior analyses using CCK-8, transwell, western blot, or flow cytometry. Potential downstream target of LINC00592 was explored using RNA pull-down assay and methylation of WIF1 was determined using methylated-specific PCR. In addition, WIF1 or/and LINC00592 were silenced in BC cells followed by cell behavior analyses to explore the regulation between them. Upregulation of LINC00592 was significantly detected in BC tissues and cells. In BC cells silencing LINC00592 suppressed the proliferation, migration, and epithelial-mesenchymal transitions (EMT), but enhanced apoptosis. Moreover, LINC00592 recruited DNMT1, DNMT3A, and DNMT3B to enhance WIF1 promoter methylation. In addition, WIF1 overexpression suppressed the proliferation, migration, as well as EMT, but enhanced apoptosis. Silencing WIF1 significantly attenuated the role of silencing LINC00592 in suppressing the proliferative, migratory, and EMT ability of BC cells, and increasing the apoptosis. LINC00592 promoted the growth and metastasis of BC via enhancing the promoter methylation of WIF1 and decreasing WIF1 transcription.
Introduction: As a member of annexin family proteins, annexin A3 (ANXA3) has 36-kDa and 33-kDa isoforms. ANXA3 plays crucial roles in the tumorigenesis, aggressiveness and drug-resistance of cancers. However, previous studies mainly focused on the role of total ANXA3 in cancers without distinguishing the distinction between the two isoforms, the role of 33-kDa ANXA3 in cancer remains unclear. Objectives: Current work aimed to investigate the function and regulation mechanism of 33-kDa ANXA3 in hepatocarcinoma. Methods: The expressions of ANXA3, CRKL, Rac1, c-Myc and pAkt were analyzed in hepatocarcinoma specimens by Western blotting. The biological function of 33-kDa ANXA3 in the growth, metastasis, apoptosis, angiogenesis, chemoresistance of hepatocarcinoma cells with the underlying molecular mechanism were investigated using gain-of-function strategy in vitro or in vivo. Results: 33-kDa ANXA3 was remarkably upregulated in tumor tissues compared with corresponding normal liver tissues of hepatocarcinoma patients. Its stable knockdown decreased the in vivo tumor growing velocity and malignancy of hepatocarcinoma HepG2 cells transplanted in nude mice. The in vitro experimental results indicated 33-kDa ANXA3 knockdown suppressed the proliferation, colony forming, migration and invasion abilities of HepG2 cells through downregulating CRKL, Rap1b, Rac1, pMEK, pERK2 and c-Myc in ERK pathway; inhibited angiogenesisability of HepG2 cells through inactivating PI3K/Akt-HIF pathway; induced apoptosis and enhanced chemoresistance of HepG2 cells through increasing Bax/decreasing Bcl-2 expressions and inactivating caspase 9/caspase 3 in intrinsic apoptosis pathway. Accordingly, CRKL, Rac1, c-Myc and pAkt were also upregulated in hepatocarcinoma patients ’ tumor tissues compared with corresponding normal liver tissues. Conclusions: The overexpression of 33-kDa ANXA3 is involved in the clinical progression of hepatocarcinoma and in the malignancy, angiogenesis and apoptosis of hepatocarcinoma cells. It is of potential use in hepatocarcinoma diagnosis and treatment.
Background: As a member of annexin family proteins, annexin A3 (ANXA3) has 36-kDa and 33-kDa isoforms, which plays important roles in aggressiveness, tumorigenesis and drug resistance in tumors. Previous studies mainly focused on the role of total ANXA3 in cancers without distinguishing the distinction between the two isoforms, the role of 33-kDa ANXA3 in cancer remains unclear. Current work established the potential role and regulation mechanism of 33-kDa ANXA3 in hepatocarcinoma. Methods: The expression patterns of ANXA3, CRKL, Rac1, c-Myc and pAkt were analyzed in hepatocarcinoma specimens by western blotting; The biological function of 33-kDa ANXA3 in hepatocarcinoma cell growth, metastasis, apoptosis, angiogenesis, chemoresistance and the underlying molecular mechanism were investigated using gain-of-function strategyin vitro or in vivo. Findings: 33-kDa ANXA3 protein was significantly upregulated in cancerous tissues compared with paracancerous non-tumor liver tissues of hepatocarcinoma patients. Its stable knockdown decreased the in vivo tumor growing velocity and malignancy of hepatocarcinoma HepG2 cells transplanted in nude mice. The in vitro experimental results indicated 33-kDa ANXA3 knockdown suppressed proliferative, colony forming, migrative and invasive abilities of HepG2 cells through downregulating CRKL, Rap1b, Rac1, pMEK, pERK2 and c-Myc in ERK pathway; inhibited angiogenesis ability of HepG2 cells through inactivating PI3K/Akt-HIF pathway; induced apoptosis and enchanced chemoresistance of HepG2 cells through increasing Bax/decreasing Bcl-2 expressions and inactivating caspase 9/caspase 3 in intrinsic apoptosis pathway. Accordingly, CRKL, Rac1, c-Myc and pAkt were also upregulated in cancerous tissues compared with paracancerous non-tumor liver tissues of hepatocarcinoma patients. Interpretation: 33-kDa ANXA3 plays vital role in hepatocarcinoma malignancy, angiogenesis and chemoresistance. It is of potential use in prognosis and therapeutics for hepatocarcinoma.Funding Statement: This work was supported by grants from National Natural Science Foundation of China (81672737, 81272186, 31900517) and Natural Science Foundation of Liaoning (LZ2019003, 20181550168, LQ2017001).Declaration of Interests: The authors declare no potential conflicts of interest.Ethics Approval Statement: Tissue use and study protocol were approved by the Medical Ethics Committee of Dalian Medical University. Informed consent was obtained from each patient. All experiment methods were performed in accordance with the relevant guidelines and regulations.