Suppressed Tumor Growth Research Articles

Discovery of Novel PROTAC-Based HPK1 Degraders with High Potency and Selectivity for Cancer Immunotherapy.

Hematopoietic progenitor kinase 1 (HPK1, MAP4K1), a serine/threonine (SER/THR) kinase, has been identified as a negative immune regulator of T-cell receptor signaling. Deprivation of the HPK1 function suppresses tumor growth, providing an attractive strategy for cancer immunotherapy. Herein, we present a novel PROTAC-based HPK1 degrader compound DD205-291 with high selectivity and potency. DD205-291 showed a dose-dependent inhibition of SLP-76 phosphorylation and an induction of IL-2 and IFN-γ. Compared with other inhibitors, DD205-291 exhibited good efficacy and a favorable safety profile in the MC38 model. Specifically, oral administration of DD205-291 at 0.5 mg/kg in combination with anti-PD1 resulted in significant suppression with a TGI value of 91.0%. Furthermore, DD205-291 exhibited a low risk of cardiotoxicity and a wide safety window. This research effort demonstrates that DD205-291 is a promising preclinical candidate (PCC) for potential mono- and comboimmunotherapy of cancer.

Astragaloside IV augments anti-PD-1 therapy to suppress tumor growth in lung cancer by remodeling the tumor microenvironment.

Programmed cell death protein-1 (PD-1) inhibitors are increasingly utilized in the treatment of lung cancer (LC). Combination therapy has recently gained popularity in treating LC. This study aimed to assess the efficacy of combining Astragaloside IV (AS-IV) and anti-PD-1 in LC. C57BL/6J mice were subcutaneously injected with Lewis lung carcinoma (LLC) cells. After 3 weeks, the animals were sacrificed, and the tumors were harvested for analysis. Ki-67 immuno-labeling and TUNEL assay were used for evaluating cell proliferation and apoptosis in tumor tissues. In addition, anti-cleaved caspase 3 was used for immunolabelling of apoptotic cells. Immune cell infiltration (macrophages and T cells) and gene expression in tumor tissues were also investigated by using immunofluorescence staining. Compared to treatment with anti-PD-1 or AS-IV, the combination of AS-IV and anti-PD-1 notably reduced tumor volume and weight of LLC-bearing mice. Additionally, the combination treatment strongly induced the apoptosis and suppressed the proliferation in tumor tissues through inactivating PI3K/Akt and ERK signaling pathways, compared to single treatment group. Moreover, the combination treatment elevated levels of the M1 macrophage marker mCD86, reduced levels of the M2 macrophage marker mCD206, as well as upregulated levels of the T cell activation marker mCD69 in tumor tissues. Collectively, the combination treatment effectively inhibited tumor growth in LLC mice through promoting M1 macrophage polarization and T cell activation. These findings showed that combining AS-IV with anti-PD-1 therapy could be a promising therapeutic approach for LC.

IL-18, a therapeutic target for immunotherapy boosting, promotes temozolomide chemoresistance via the PI3K/AKT pathway in glioma

Interleukin-18, a member of the interleukin − 1 family of cytokines, is upregulated in glioma. However, its effects on glioma remain unclear. This study aimed to explore the role and underlying mechanisms of interleukin-18 expression in glioma. Here, we demonstrated that interleukin-18 enhanced resistance to temozolomide by increasing proliferation and inhibiting apoptosis in cultured glioma cells. Further in vivo studies revealed that interleukin-18 promoted temozolomide resistance in BALB/c nude mice bearing tumor. Mechanical exploration indicated that interleukin-18 stimulation could activate the PI3K/AKT signaling pathway in glioma cells, and PI3K inhibition could reduce the temozolomide resistance promoted by interleukin-18. We found that interleukin-18 upregulated CD274 expression in glioma, revealing its potential effects on the microenvironment. Furthermore, we established a tumor xenograft model and explored the therapeutic efficacy of anti-interleukin-18 monoclonal antibody. Targeting interleukin-18 prolonged survival and attenuated CD274 expression in the mice bearing tumor. Combined treatment with anti-interleukin-18 and anti-PD-1 monoclonal antibody showed better efficacy in suppressing tumor growth than either treatment alone in mice bearing tumor. Collectively, these data present that interleukin-18 promotes temozolomide chemoresistance in glioma cells via PI3K/Akt activation and establishes an immunosuppressive milieu by modulating CD274. This study highlights the therapeutic value of interleukin-18 in glioma.

Enabling oral novel Taxanes-based Chemotherapy with Lipophilic prodrug Self-nanoemulsifying drug delivery system

Larotaxel (LTX) and SB-T-1214 (SBT), two new synthetic experimental toxoids, have shown broad-spectrum antitumor activity, especially against tumors that are resistant to other drugs. However, their poor solubility, membrane permeability, and first-pass effect limits their use in oral administration. We designed and synthesized two long-chain triglyceride-mimic prodrugs of LTX (LTXSSTG) and SBT (SBTSSTG), which are bridged by disulfide bonds and efficiently incorporated them into Self-nanoemulsifying drug delivery system (SNEDDS). These prodrugs can bypass hepatic metabolism by entering the blood through intestinal lymphatic transport, following a similar oral absorption pathway to dietary lipids. It was found that LTXSSTG and SBTSSTG significantly improved oral bioavailability (about 4.5-fold for LTX and 3.4-fold for SBT) compared to their solution forms. Moreover, with LTXSSTG and SBTSSTG incorporating reduction stimulus-responsive spacer were much more effective in suppressing tumor growth in vivo with eliminated adverse effects than solution form. To sum up, this strategy provides a new avenue to enhance oral delivery of new toxoids.

Abstract A047: Activation of conventional type 2 dendritic cells (cDC2) by anti-CD47 may enhance antitumor T cell function in mouse liver cancer models

Abstract Anti-CD47 has been extensively studied for its effects on activating phagocytosis by blocking the ‘don’t eat me’ signal presented by CD47 expressed on cancer cells. This study explored the effects of anti-CD47 on enhancing antigen presentation by dendritic cells and improving antigen-specific antitumor immunity. Mouse Hepa1-6 liver cancer cells with or without over-expression of LCMV-GP protein and splenocytes from P14 transgenic mice were used to test antigen-specific antitumor immunity. Bone marrow-derived conventional type 1 and type 2 dendritic cells (cDC1 and cDC2) or MutuDC1/ DC2 cell lines were co-cultured with CD8 T cells with or without exhaustion. Effects of anti-CD47 on the cross-priming ability of DC were analyzed by T cell proliferation (CSFE labeling), activation (expression of IFNγ, granzyme B, TNFa, and IL-2), cell killing (in vitro cytotoxicity assay) and T cell exhaustion (LAG3, TOX, PD1 expression). In vivo studies indicated that anti-CD47 treatment may suppress tumor growth, activate intra-tumoral cDC2 but not type 1 dendritic cells (cDC1), and delay CD8 T cells from entering terminal exhaustion in the tumor microenvironments. In vitro studies indicated that anti-CD47 may enhance the priming ability of cDC2, but not cDC1, and increase ISG15 expression in cDC2. When co-cultured with exhausted T cells, anti-CD47-treated cDC2 may delay the exhaustion process and restore antigen-specific effector function and cytotoxic capacity. Conclusion: Anti-CD47 may enhance antitumor T cell function in mouse liver cancer models by activation of cDC2, which may serve as a new strategy of developing immunotherapeutic agents for liver cancer (supported by grants NSTC 111- 2314-B-002-039 and 113-2314-B-002-113-MY3). Citation Format: Cheng-Zhe Jian, Da-Liang Ou, Chia-Lang Hsu, Chien-Kuo Lee, Chiun Hsu. Activation of conventional type 2 dendritic cells (cDC2) by anti-CD47 may enhance antitumor T cell function in mouse liver cancer models [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor Immunology and Immunotherapy; 2024 Oct 18-21; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2024;12(10 Suppl):Abstract nr A047.

"Trinity" Comprehensively Regulates the Tumor Microenvironment of Lipid-Coated CaCO3@CuO2 Nanoparticles Induces "Cuproptosis" in HCC.

Tumor cell death induced by "cuproptosis" is a novel form of tumor death that differs from apoptosis induced by chemotherapy. It is expected to emerge as a new approach for cancer treatment. In this study, our focus was on exploiting the characteristic of "cuproptosis" which necessitates increased aerobic respiration to induce tumor cell death. To achieve this, we developed a novel drug delivery system using a CaCO3@CuO2 lipid coating (CaCO3@CuO2@L). This system aimed to comprehensively modulate the tumor microenvironment and trigger "cuproptosis" in hepatocellular carcinoma (HCC) through the interaction between copper ions and peroxides. Experimental results revealed that the CaCO3@CuO2@L exhibited a distinct watermelon shape, with CuO2 evenly distributed within the CaCO3 nanoparticles. The nanoparticles had an average size of approximately 191 nm. In vitro studies demonstrated that the nanoparticles released CuO2 in a slightly acidic environment while simultaneously elevating pH levels, reducing glutathione (GSH), and increasing oxygen production. Within liver cancer cells, the CaCO3@CuO2@L effectively regulated the acidity, GSH levels, and oxygen-depleted microenvironment through the "trinity" mechanism, ultimately inducing "cuproptosis" in HCC. Furthermore, in mouse models with transplanted tumors and orthotopic liver cancer tumors, the CaCO3@CuO2@L significantly suppressed tumor growth. By triggering "cuproptosis" in HCC, this study offers valuable insights for developing a comprehensive treatment approach for HCC. Ultimately, this research may pave the way for the clinical implementation of the drug delivery system based on "cuproptosis" in liver cancer treatment.

RNA binding protein ZCCHC24 promotes tumorigenicity in triple-negative breast cancer.

Triple-negative breast cancer (TNBC) lacks the expression of hormone and HER2 receptors and is highly malignant with no effective therapeutic targets. In TNBC, the cancer stem-like cell (CSC) population is considered to be the main cause of resistance to treatment. Thus, the therapeutic targeting of this population could substantially improve patient survival. Here, we identify the RNA-binding protein ZCCHC24 as enriched in the mesenchymal-like TNBC population. ZCCHC24 promotes the expression of a set of genes related to tumorigenicity and treatment resistance by directly binding to the cis-element "UGUWHWWA" in their mRNAs, thereby stabilizing them. One of the ZCCHC24 targets, ZEB1, is a transcription factor that promotes the expression of cancer stemness genes and reciprocally induces ZCCHC24 expression. ZCCHC24 knockdown by siRNAs shows a therapeutic effect and reduces the mesenchymal-like cell population in TNBC patient-derived xenografts. ZCCHC24 knockdown also has additive effects with the BET inhibitor JQ1 in suppressing tumor growth in TNBC patient-derived xenografts.

Disturbing microtubule-endoplasmic reticulum dynamics by gold nanoclusters for improved triple-negative breast cancer treatment.

Microtubules are highly dynamic structures, and their dynamic instability is indispensable for not only cell growth and movement, but also stress responses, such as endoplasmic reticulum (ER) stress. Docetaxel, a microtubule targeting agent (MTA), is the first-line drug for cancer treatment by simultaneously promoting microtubule dysregulation- and ER stress-induced cell death. However, it also causes adverse effects and drug resistance, especially in triple-negative breast cancer (TNBC) with a poor prognosis and high mortality rate. In this study, we developed a peptide-templated gold nanocluster, namely GA. GA significantly sensitizes TNBC cells to docetaxel, causing severe cell death. This effect is further validated by a 3D tumor spheroid model. Mechanistically, GA disrupted microtubule dynamic instability, meanwhile promoting PERK-mediated ER stress. Interestingly, ER stress inhibitors profoundly suppressed microtubule dysregulation, suggesting a retrograde regulation of ER stress on microtubules. In vivo, the combined administration of docetaxel and GA significantly suppresses tumor growth while docetaxel alone cannot. GA similarly elevated the level of caspases and PERK within tumors as in vitro. Importantly, GA treatment also profoundly promoted the production of anti-tumor inflammatory cytokines. Collectively, we developed an ER-microtubule regulatory nanomaterial that enhanced the therapeutic effect of docetaxel by elevating tumor cell death and anti-tumor cytokine production, providing a potential supplemental strategy for TNBC treatment.

Heparin-binding EGF-like growth factor via miR-126 controls tumor formation/growth and the proteolytic niche in murine models of colorectal and colitis-associated cancers

MicroRNAs, including the tumor-suppressor miR-126 and the oncogene miR-221, regulate tumor formation and growth in colitis-associated cancer (CAC) and colorectal cancer (CRC). This study explores the impact of the epithelial cytokine heparin-binding epidermal growth factor (HB-EGF) and its receptor epidermal growth factor receptor (EGFR) on the pathogenesis of CAC and CRC, particularly in the regulation of microRNA-driven tumor growth and protease expression. In murine models of CRC and CAC, lack of miR-126 and elevated miR-221 expression in colonic tissues enhanced tumor formation and growth. MiR-126 downregulation in colon cells established a pro-tumorigenic proteolytic niche by targeting HB-EGF-active metalloproteinase-7, -9 (MMP7/MMP9), disintegrin, and metalloproteinase domain-containing protein 9, and modulating chemokine-mediated recruitment of HB-EGF-loaded inflammatory cells. Mechanistically, downregulation of HB-EGF and EGFR in the colon suppressed miR-221 and enhanced miR-126 expression via activating enhancer-binding protein 2 alpha. Reintroducing miR-126 reduced tumor development and HB-EGF expression. Combining miR-126 reintroduction, which targets specific HB-EGF-active proteases but not ADAM17, with MMP inhibitors like Batimastat or Marimastat effectively suppressed tumor growth. This combination normalized protease expression and balanced miR-126 and miR-221 levels in developing and growing tumors. These findings demonstrate that suppressing HB-EGF and EGFR1 shifts the balance from oncogenic miR-221 to tumor-suppressive miR-126 action. Consequently, normalizing miR-126 expression could open new avenues for treating patients with CAC and CRC, and this normalization is intertwined with the anticancer efficacy of MMP inhibitors.

Suppressing Pancreatic Cancer Survival and Immune Escape via Nanoparticle-Modulated STING/STAT3 Axis Regulation.

Pancreatic ductal adenocarcinoma (PDAC) poses a challenge in oncology due to its high lethality and resistance to immunotherapy. Recently, emerging research on the stimulator of interferon gene (STING) pathway offers novel opportunities for immunotherapy. Although STING expression is retained in PDAC cells, the response of PDAC cells to STING agonists remains ineffective. Signal transducer and activator of transcription 3 (STAT3), a downstream pathway of STING, is notably overexpressed in pancreatic cancer and related to tumor survival and immune escape. We observed that inhibiting STAT3 signaling post-STING activation effectively suppressed tumor growth through signal transducer and activator of transcription 1 (STAT1)-mediated apoptosis but led to a potential risk of immune-related adverse events (irAEs). To address this issue, we designed a tumor-penetrating liposome for the codelivery of STING agonist and STAT3 inhibitor. These nanoparticles regulated the STING/STAT3 signaling axis and effectively inhibited the proliferation and survival of tumor. Simultaneously, we found a significant increase in the activation of NK cells and CD8+ T cells after treatment, leading to robust innate immunity and adaptive immune response. We highlight the potential of regulating the STING/STAT3 axis as a promising treatment for improving clinical outcomes in PDAC patients.

Hollow Calcium/Copper Bimetallic Amplifier for Cuproptosis/Paraptosis/Apoptosis Cancer Therapy via Cascade Reinforcement of Endoplasmic Reticulum Stress and Mitochondrial Dysfunction.

The endoplasmic reticulum (ER) and mitochondria are essential organelles that play crucial roles in maintaining cellular homeostasis. The simultaneous induction of ER stress and mitochondrial dysfunction represents a promising yet challenging strategy for cancer treatment. Herein, a hollow calcium-copper bimetallic nanoplatform is developed as a cascade amplifier to reinforce ER stress and mitochondrial dysfunction for breast cancer treatment. For this purpose, we report a facile method for preparing hollow CaCO3 (HCC) nanoparticles by regulating the dissolution-recrystallization process of amorphous CaCO3, and the amplifier D@HCC-CuTH is meticulously fabricated by sequentially coating disulfiram-loaded HCC nanoparticles with a copper coordination polymer and hyaluronan. In tumor cells, the dithiocarbamate-copper complex generated in situ by liberated disulfiram and Cu2+ inhibits the ubiquitin-proteasome system, causing irreversible ER stress and intracellular Ca2+ redistribution. Meanwhile, the amplifier induces mitochondrial dysfunction via triggering a self-amplifying loop of mitochondrial Ca2+ burst, and reactive oxygen species augment. Additionally, Cu2+ induces dihydrolipoamide S-acetyltransferase oligomerization in mitochondria, further exacerbating mitochondrial damage via cuproptosis. Collectively, ER stress amplification and mitochondrial dysfunction synergistically induce a cuproptosis-paraptosis-apoptosis trimodal cell death pathway, which demonstrates significant efficacy in suppressing tumor growth. This study presents a paradigm for synchronously inducing subcellular organelle disorders to boost cancer multimodal therapy.

E2F1-induced upregulation of TROAP contributes to endometrial cancer progression.

To investigate the role of Trophinin-associated protein (TROAP) in endometrial cancer (EC) progression and elucidate how the transcription factor E2F transcription factor 1 (E2F1) modulates EC by upregulating TROAP expression. TROAP expression in EC tissues and cell lines was analyzed using bioinformatics databases, quantitative real-time polymerase chain reaction (qRT-PCR), western blot, and immunohistochemistry. TROAP was knocked down in EC cells to assess its effects on proliferation, migration, invasion, and glycolysis. Potential transcription factors regulating TROAP were identified, and the relationship between E2F1 and TROAP gene regulation was examined using dual luciferase assay. In vivo tumor growth was evaluated using a mouse xenograft model. TROAP was overexpressed in EC tissues and cell lines compared with normal controls. High TROAP expression correlated with poor differentiation, advanced stage, lymph node metastasis, and worse overall survival in EC patients. Knockdown of TROAP inhibited the proliferation, migration, invasion, and glycolytic capacity of EC cells. E2F1 was identified as a transcriptional activator of TROAP. E2F1 overexpression enhanced TROAP expression and promoted EC cell proliferation, migration, and glycolysis in a TROAP-dependent manner. TROAP knockdown suppressed tumor growth in vivo. TROAP is transcriptionally activated by E2F1 and promotes EC progression by enhancing cell proliferation, metastasis, and glycolysis. The E2F1-TROAP axis may serve as a potential therapeutic target for EC treatment.

SMAC mimetic BV6 acts in synergy with mTOR inhibitor to increase cisplatin sensitivity in ovarian cancer.

The objective of this study is to observe the antitumor efficacy of the second mitochondria-derived activator of caspases (SMAC) mimetic bivalent smac mimetic (BV6) in combination with target of rapamycin (mTOR) inhibitor on DDP (cisplatin) sensitivity. Ovarian cancer cells were exposed to cisplatin, BV6, DDP + BV6, and DDP + BV6 + mTOR inhibitor Rapamycin. Using proteomics and bioinformatics, protein expression profiles in ovarian cancer were determined. Bagg Albino color nude mice were treated with DDP or BV6 alone or in combination, or BV6 + DDP + Rapamycin. The effects of different treatments on ovarian cancer cells and tumor growth were evaluated in vivo and in vitro. Proteomics and bioinformatics analysis revealed significant changes of protein kinase (AKT)/mTOR pathway. Consistently, western blot data indicated that AKT/mTOR axis was gradually activated in BV6-treated ovarian cancer cells and attenuated the cytotoxic effect of BV6. Functional assays showed that DDP or BV6 treatment alone significantly enhanced the sensitivity and inhibited the migration of ovarian cancer cells, but without any synergistic effects. In addition, combination with BV6 and mTOR inhibitor Rapamycin significantly decreased cell viability and inhibited migration of ovarian cancer cells exposed to DDP. Consistently, the xenograft model showed that co-treatment with Rapamycin with BV6 had significantly suppressed tumor growth and metastasis. Our study demonstrated that SMAC analogue BV6 exhibits a strong anticancer effect on ovarian cancer in vitro and in vivo. Combination with Rapamycin overcomes the activation of mTOR pathway by BV6 and increases the chemosensitivity to DDP. These data suggest a potential application of triple combination with DDP + BV6 + Rapamycin in clinical management of ovarian cancer.

Circadian rhythms of macrophages are altered by the acidic tumor microenvironment

Tumor-associated macrophages (TAMs) are prime therapeutic targets due to their pro-tumorigenic functions, but varying efficacy of macrophage-targeting therapies highlights our incomplete understanding of how macrophages are regulated within the tumor microenvironment (TME). The circadian clock is a key regulator of macrophage function, but how circadian rhythms of macrophages are influenced by the TME remains unknown. Here, we show that conditions associated with the TME such as polarizing stimuli, acidic pH, and lactate can alter circadian rhythms in macrophages. While cyclic AMP (cAMP) has been reported to play a role in macrophage response to acidic pH, our results indicate pH-driven changes in circadian rhythms are not mediated solely by cAMP signaling. Remarkably, circadian disorder of TAMs was revealed by clock correlation distance analysis. Our data suggest that heterogeneity in circadian rhythms within the TAM population level may underlie this circadian disorder. Finally, we report that circadian regulation of macrophages suppresses tumor growth in a murine model of pancreatic cancer. Our work demonstrates a novel mechanism by which the TME influences macrophage biology through modulation of circadian rhythms.

Mechanism of APC truncation involved in colorectal cancer tumorigenesis (Review).

Adenomatous polyposis coli (APC) is widely recognized as a heavily mutated gene that suppresses tumor growth in colorectal cancer (CRC). Its mutation is considered to be the primary and early event that occurs in the development of CRC. In addition, APC has a crucial role in inhibiting the canonical Wnt signaling pathway. APC mutations in CRC result in the production of shortened gene products. This impairment of β-catenin destruction complexes causes an accumulation of active β-catenin in the cytoplasm and nucleus. In these compartments, β-catenin can bind with DNA-binding proteins of the transcription factor/lymphoid enhancer-binding factor family, thereby activating the Wnt signaling pathway. Consequently, the balance of numerous cellular processes is disrupted, ultimately driving the formation of tumors. There is a growing body of evidence indicating the prevalent occurrence of APC truncation in the majority of CRC cases. Furthermore, it has been observed that these truncated proteins have a crucial role in the activation of the Wnt signaling pathway and the subsequent loss of tumor inhibitory function. This review aimed to provide an overview of the recent advancements in understanding the mechanism behind APC truncation and its association with the onset and progression of CRC.

Association of glutaminase expression with immune-suppressive tumor microenvironment, clinicopathologic features, and clinical outcomes in endometrial cancer

ObjectiveIncreased glutamine metabolism by cancer cells via upregulation of the drug-targetable enzyme glutaminase may contribute to an immune-suppressive tumor microenvironment. Inhibiting glutamine metabolism can not only suppress tumor growth, but...

Intracellular Generation of Alkyl Radicals Enabled by a Self-Catalytic ATRP Nanoinitiator.

Oxygen-independent alkyl radicals (R•) have demonstrated great promise in combating tumor hypoxia. Currently, Azo compounds have been the primary source of R•, suffering from external stimuli and decomposition during circulation. Herein, we developed a self-catalytic ATRP nanoinitiator that could generate R• via glutathione (GSH) reduction and thus selectively induce apoptosis of tumor cells. Specifically, a conjugation of laccase (possessing a copper(II) complex) and polymeric alkyl bromide, poly(iBBr), was fabricated to yield an ATRP nanoinitiator (Lac-P(iBBr)). After internalization by cells featured with overexpressed GSH, copper(II) in Lac-P(iBBr) was reduced to copper(I) by GSH, which abstracted the Br atom in poly(iBBr) to yield toxic R•. Moreover, GSH-depletion intensified the oxidative damage caused by R•. Efficient generation of R• by Lac-P(iBBr) could happen in lab flasks, living cells, and tumor-bearing mice without any external stimuli, as demonstrated by the radical product, as well as the consumption of GSH. Moreover, the self-catalytic ATRP nanoinitiator significantly induced cell apoptosis and suppressed tumor growth. Our study expands the chemical toolbox to manipulate cell fates.

Innovative Oral Nano/Gene Delivery System Based on Engineered Modified Saccharomyces cerevisiae for Colorectal Cancer Therapy.

The efficient delivery of RNA-based drugs to solid tumors remains a formidable obstacle. We aim to develop a safe and efficient oral drug delivery system compatible with RNA-based drugs that is urgently needed to overcome challenges such as enzymatic degradation and gastrointestinal barriers to facilitate effective treatment for treating colorectal cancer (CRC). To address these challenges, we utilized engineered modified Saccharomyces cerevisiae to evaluate the delivery efficacy of miR21-antagomir for treating CRC in preclinical mouse models, including adenomatosis polyposis coli mutant transgenic mice ApcMin/+ and in situ tumor-bearing mice. An orally deliverable gene delivery system, YS@NPs21, was designed. This gene delivery system demonstrated effectively suppressed tumor growth in both ApcMin/+ and in situ tumor-bearing mice models. This system exhibited tumor-targeting capability, effective inhibition of tumor growth, and low toxicity toward nontumor cells. Successful implementation of this innovative oral drug delivery system could offer a straightforward, safe, and RNA drug-compatible approach to CRC treatment, ultimately improving patient outcomes and reducing medical costs.

Astaxanthin Is a Novel Candidate for Glioblastoma Treatment? A Review.

Glioblastoma (GBM) is a malignant primary brain tumor with a poor prognosis and high recurrence rates. At present, the current treatments available for GBM patients can only prolong their overall survival and cannot provide a complete cure. Discovering an effective therapy against the disease is a challenge due to its recurrence and resistance to common available treatments for GBM. Several natural products have been documented to possess the potential to function as anticancer agents through diverse mechanisms. Astaxanthin (AXT) is an orange-red pigment that is a natural lipophilic and xanthophyll carotenoid derived mostly from microalgae. Numerous studies have examined that AXT impacts GBM cells in laboratory settings and animal models. This review aims to provide the latest information about the potential of astaxanthin as a novel therapeutic option for GBM. AXT has been targeted more on reactive oxygen species (ROS), and suppressed tumor growth in vitro and in vivo conditions. The available data suggests that AXT might serve as a key component in the development of innovative cancer therapies, especially for glioblastoma.

Plasmodium infection downregulates hypoxia‑inducible factor 1α expression to suppress the vascularization and tumorigenesis of liver cancer.

Liver cancer is characterized by hypervascularization. Anti-angiogenic agents may normalize the tumor vasculature and improve the efficacy of other treatments. The present study aims to investigate the anti-angiogenic effect of Plasmodium infection in a mouse model of implanted liver cancer cells. HepG2 cells were injected into the left liver lobe of nude mice as a model of in situ hepatic tumorigenesis. Plasmodium yoelii parasitized erythrocytes were administered in the animal model of liver cancer to introduce Plasmodium infection. The tumor growth and microvascular density were determined in the presence or absence of Plasmodium infection. The expression levels of hypoxia-inducible factor 1α (HIF-1α) and angiogenesis-related factors were evaluated using western blotting and reverse transcription-quantitative PCR analysis. The results demonstrated that Plasmodium infection suppressed tumor growth and vascularization in the mouse model of implanted HepG2 cells. Plasmodium parasites reduced the expression of pro-angiogenic factors (vascular endothelial growth factor A and angiopoietin 2), matrix metalloproteinases [(MMP)2 and MMP9] and inflammatory cytokines [tumor necrosis factor α, interleukin 6 (IL)-6) and IL-1β] in both hepatic and tumor tissues. HIF-1α was downregulated in both hepatic and tumor tissues upon Plasmodium infection, and HIF-1α overexpression rescued angiogenesis and tumor growth under the condition of Plasmodium infection. In conclusion, the results of the present study demonstrated the anti-angiogenic and anti-tumorigenic effects of Plasmodium infection on liver cancer through downregulating HIF-1α expression, indicating that Plasmodium parasites could be developed as an intervention strategy to restrain neo-angiogenesis in liver cancer.