Antitumor Efficacy Research Articles

Multicompartment Polyion Complex Micelles Based on Triblock Polypept(o)ides Mediate Efficient siRNA Delivery to Cancer-Associated Fibroblasts for Antistromal Therapy of Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is the most frequent type of primary liver cancer and the third leading cause for cancer-related death worldwide. The tumor is difficult-to-treat due to its inherent resistance to chemotherapy. Antistromal therapy is a novel therapeutic approach, targeting cancer-associated fibroblasts (CAF) in the tumor microenvironment. CAF-derived microfibrillar-associated protein 5 (MFAP-5) is identified as a novel target for antistromal therapy of HCC with high translational relevance. Biocompatible polypept(o)ide-based polyion complex micelles (PICMs) constructed with a triblock copolymer composed of a cationic poly(l-lysine) complexing anti-MFAP-5 siRNA (siMFAP-5) via electrostatic interaction, a poly(γ-benzyl-l-glutamate) block loading cationic amphiphilic drug desloratatine (DES) via π-πinteraction as endosomal escape enhancer and polysarcosine poly(N-methylglycine) for introducing stealth properties, are generated for siRNA delivery. Intravenous injection of siMFAP-5/DES PICMs significantly reduces the hepatic tumor burden in a syngeneic implantation model of HCC, with a superior MFAP-5 knockdown effect over siMFAP-5 PICMs or lipid nanoparticles. Transcriptome and histological analysis reveal that MFAP-5 knockdown inhibited CAF-related tumor vascularization, suggesting the anti-angiogenic effect of RNA interference therapy. In conclusion, multicompartment PICMs combining siMFAP-5 and DES in a single polypept(o)ide micelle induce a specific knockdown of MFAP-5 and demonstrate a potent antitumor efficacy (80% reduced tumor burden vs untreated control) in a clinically relevant HCC model.

Integrating Theory with Experimental Studies on the Directed Assembly of Phenforminium 5-Fluorouracilate toward Enhanced In Vitro/Vivo Properties and Synergistic Antitumor Efficacy

Integrating Theory with Experimental Studies on the Directed Assembly of Phenforminium 5-Fluorouracilate toward Enhanced <i>In Vitro</i>/<i>Vivo</i> Properties and Synergistic Antitumor Efficacy

Light-Activated In Situ Vaccine with Enhanced Cytotoxic T Lymphocyte Infiltration and Function for Potent Cancer Immunotherapy.

In situ cancer vaccination is an attractive strategy that stimulates protective antitumor immunity. Cytotoxic T lymphocytes (CTLs) are major mediators of the adaptive immune defenses, with critical roles in antitumor immune response and establishing immune memory, and are consequently extremely important for in situ vaccines to generate systemic and lasting antitumor efficacy. However, the dense extracellular matrix and hypoxia in solid tumors severely impede the infiltration and function of CTLs, ultimately compromising the efficacy of in situ cancer vaccines. To address this issue, a robust in situ cancer vaccine, Au@MnO2 nanoparticles (AMOPs), based on a gold nanoparticle core coated with a manganese dioxide shell is developed. The AMOPs modulated the unfavorable tumor microenvironment (TME) to restore CTLs infiltration and function and efficiently induced immunogenic cell death. The Mn2+-mediated stimulator of the interferon genes pathway can be activated to further augment the therapeutic efficacy of the AMOPs. Thus, the AMOPs vaccine successfully elicited long-lasting antitumor immunity to considerably inhibit primary, recurrent, and metastatic tumors. This study not only highlights the importance of revitalizing CTLs efficacy against solid tumors but also makes progress toward overcoming TME barriers for sustained antitumor immunity.

Synergistic Antitumor and Apoptotic Activity of Sitagliptin or Linagliptin Plus Cisplatin Against A549 Lung Cancer Cells (an Invitro Study)

Objective: Lung cancer (LC) has the highest mortality rate globally. Most chemotherapeutic medicines now in use are cytotoxic, prompting the search for novel compounds with anticancer properties and improved safety profiles for normal cells. Dipeptidyl peptidase-4 inhibitors have demonstrated anticancer effects and apoptotic properties by specifically inhibiting dipeptidyl peptidase -4, a glycoprotein found in various organs that support the spread of cancer and tumor formation. Based on that, this study aimed to evaluate the cytotoxicity and apoptotic activity of sitagliptin (SITA) and linagliptin (LINA) against the lung cancer cell line (A549) alone and in combination with cisplatin (CP). Methods: A549 cells were categorized into six groups: control (untreated cells), CP-treated cells, SITA-treated cells, LINA-treated cells, CP plus SITA treated cells (1:1 ratio), and CP plus LINA treated cells (1:1 ratio). After 72 hours of incubation, cell viability (or cytotoxicity) and concentration required to inhibit 50% of cell viability (IC50) for each group were determined using an MTT assay. This method is safe and easy to use, has more reproducibility, and is commonly used for cell viability and cytotoxicity tests. Later, A549 cells were cultured in six flasks and exposed to the IC50 for 36 hours. Afterward, the cells were harvested and centrifuged, and the supernatant was removed. The remaining cell pellets were collected and lysed using a lysis buffer to measure B-cell lymphoma type 2 (BCL-2) levels with ELISA test kits. The data was collected and subjected to statistical analysis techniques. Results: MTT assay results determined that SITA and LINA significantly increased A549 cell cytotoxicity compared to the control group (P&lt;0.0001). Moreover, combining SITA or LINA with CP showed markedly increased antitumor efficacy and more significant cytotoxicity directed toward A549 cells. Additionally, these combinations highly reduced IC50 in comparison to monotherapy. Considerably, both drugs showed remarkable apoptotic activity on A549 cells when used alone or combined with CP by decreasing BCL2 levels. Consequently, it potentiates apoptotic effects and cytotoxicity of CP against cancer cells. Interestingly, Lina was more potent than Sita regarding cytotoxicity and apoptotic activity on A549 cells. Conclusion: SITA and Lina exhibited significant cytotoxic and apoptotic effects against A549 cells through the induction of apoptosis. Notably, the results suggest a potential synergistic anticancer impact on CP.

Tumor-intrinsic IFNα and CXCL10 are critical for immunotherapeutic efficacy by recruiting and activating T lymphocytes in tumor microenvironment

Tumor immunotherapies targeting PD-(L)1 exhibit anti-tumor efficacy in only 10–30% of patients with various cancers. Literature has demonstrated that a “hot tumor” which contains high T lymphocytes in the tumor microenvironment exhibits a better response to immunotherapies than a “cold tumor.” This study aimed to investigate whether tumor-intrinsic IFNα and CXCL10 determine the recruitment and activation of CD8+ T cells to become “hot tumor.” In this study, we found that CXCL10 overexpressed in a variety of tumors including lung, colon, and liver tumors with a correlation with PD-L1. High PD-L1 and CXCL10 are associated with better survival rates in tumor patients receiving immunotherapies. IFNs-downstream transcriptional factor IRF-1 and STAT1 were correlated with PD-L1 and CXCL10 expression. We demonstrated that IRF-1 and STAT1 were both bound with the promoters of PD-L1 and CXCL10, sharing the same signaling pathway and determining IFNs-mediated PD-L1 and CXCL10 expression. In addition, IFNα significantly increased activation marker IFNγ in PBMCs, promoting M1 type monocyte differentiation, CD4+ T, and CD8+ T cell activation. Particularly, we found that CD8+ T lymphocytes abundantly expressed CXCR3, a receptor of CXCL10, by flow cytometry, indicating that tumor-intrinsic CXCL10 potentially recruited CD8+ T in tumor microenvironment. To demonstrate the hypothesis, immunotherapy-sensitive CT26 and immunotherapy-resistant LL/2 were used and we found that CT26 cells exhibited higher IFNα, IFNγ, CXCL10, and PD-L1 levels compared to LL/2, leading to higher IFNγ expression in mouse splenocytes. Moreover, we found that CD8+ T cells were recruited by CXCL10 in vitro, whereas SCH546738, an inhibitor of CXCR3, inhibited T cell migration and splenocytes-mediated anti-tumor effect. We then confirmed that CT26-derived tumor was sensitive to αPD-L1 immunotherapy and LL/2-tumor was resistant, whereas αPD-L1 significantly increased T lymphocyte activation marker CD107a in CT26-derived BALB/c mice. In conclusion, this study revealed that CXCL10 expression is correlated with PD-L1 in tumors, sharing the same signaling pathway and associating with better immunotherapeutic efficacy. Further evidence in the syngeneic tumor models demonstrated that immunotherapy-sensitive CT26 intrinsically exhibited higher IFNα and CXCL10 compared to immunotherapy-resistant LL/2 to recruit and activate CD8+ T cells in the tumor microenvironment, exhibiting “hot tumor” characteristic of sensitizing αPD-L1 immunotherapies.

The Evolving Paradigm of Antibody–Drug Conjugates Targeting the ErbB/HER Family of Receptor Tyrosine Kinases

Current therapies targeting the human epidermal growth factor receptor (HER) family, including monoclonal antibodies (mAbs) and tyrosine kinase inhibitors (TKIs), are limited by drug resistance and systemic toxicities. Antibody–drug conjugates (ADCs) are one of the most rapidly expanding classes of anti-cancer therapeutics with 13 presently approved by the FDA. Importantly, ADCs represent a promising therapeutic option with the potential to overcome traditional HER-targeted therapy resistance by delivering highly potent cytotoxins specifically to HER-overexpressing cancer cells and exerting both mAb- and payload-mediated antitumor efficacy. The clinical utility of HER-targeted ADCs is exemplified by the immense success of HER2-targeted ADCs including trastuzumab emtansine and trastuzumab deruxtecan. Still, strategies to improve upon existing HER2-targeted ADCs as well as the development of ADCs against other HER family members, particularly EGFR and HER3, are of great interest. To date, no HER4-targeting ADCs have been reported. In this review, we extensively detail clinical-stage EGFR-, HER2-, and HER3-targeting monospecific ADCs as well as novel clinical and pre-clinical bispecific ADCs (bsADCs) directed against this receptor family. We close by discussing nascent trends in the development of HER-targeting ADCs, including novel ADC payloads and HER ligand-targeted ADCs.

Enhancing the Antitumor Efficacy of Oncolytic Adenovirus Through Sonodynamic Therapy-Augmented Virus Replication.

The therapeutic efficacy of oncolytic adenoviruses (OAs) relies on efficient viral transduction and replication. However, the limited expression of coxsackie-adenovirus receptors in many tumors, along with the intracellular antiviral signaling, poses significant obstacles to OA infection and oncolysis. Here, we present sonosensitizer-armed OAs (saOAs) that potentiate the antitumor efficacy of oncolytic virotherapy through sonodynamic therapy-augmented virus replication. The saOAs could not only efficiently infect tumor cells via transferrin receptor-mediated endocytosis but also exhibit enhanced viral replication and tumor oncolysis under ultrasound irradiation. We revealed that the sonosensitizer loaded on the viruses induced the generation of ROS within tumor cells, which triggered JNK-mediated autophagy, ultimately leading to the enhanced viral replication. In mouse models of malignant melanoma, the combination of saOAs and sonodynamic therapy elicited a robust antitumor immune response, resulting in significant inhibition of melanoma growth and improved host survival. This work highlights the potential of sonodynamic therapy in enhancing the effectiveness of OAs and provides a promising platform for fully exploiting the antitumor efficacy of oncolytic virotherapy.

Stimuli-Responsive mRNA Vaccines to Induce Robust CD8+ T Cell Response via ROS-Mediated Innate Immunity Boosting.

The messenger RNA (mRNA) vaccines hold great significance in contagion prevention and cancer immunotherapy. However, safely and effectively harnessing innate immunity to stimulate robust and durable adaptive immune protection is crucial, yet challenging. In this study, we synthesized a library of stimuli-responsive bivalent ionizable lipids (srBiv iLPs) with smart molecular blocks responsive to esterase, H2O2, cytochrome P450, alkaline phosphatase, nitroreductase, or glutathione (GSH), aiming to leverage physiological cues to trigger fast lipid degradation, promote mRNA translation, and induce robust antitumor immunity via reactive oxygen species (ROS)-mediated boosting. After subcutaneous immunization, esterase-responsive vaccine (eBiv-mVac) was rapidly internalized and transported into the draining lymph nodes. It then underwent fast decaging and self-immolative degradation in esterase-rich antigen-presenting cells, releasing sufficient mRNA for antigen translation and massive reactive quinone methides to elevate ROS levels. This resulted in broad activation of innate immunity to boost T cell response, prompting a large number of primed antigen-specific CD8+ T cells to circulate and infiltrate into tumors (>1000-fold versus unvaccinated control), thereby orchestrating innate and adaptive immunity to control tumor growth. Moreover, by further combining our vaccination strategy with immune checkpoint blockade, we demonstrated a synergism that significantly amplified the magnitude and function of antigen-specific CD8+ T cells. This, in turn, caused potent systemic antitumor efficacy and prolonged survival with high complete response rate in xenograft and metastasis models. Overall, our generalized stimuli-responsive mRNA delivery platform promises a paradigm shift in the design of potent vaccines for cancer immunotherapy, as well as effective and precise carriers for gene editing, protein replacement, and cell engineering.

Cryoablation combined with dual immune checkpoint blockade enhances antitumor efficacy in hepatocellular carcinoma model mice

Background Cryoablation (Cryo) is a minimally invasive treatment for tumors. Cryo can activate the body’s immune response, although it is typically weak. The immune response induced by Cryo in hepatocellular carcinoma (HCC) is poorly understood. PD-1 and CTLA-4 monoclonal antibodies are immune checkpoint inhibitors used in immunotherapy for tumors. The combined use of these antibodies with Cryo may enhance the immune effect. Methods A Balb/c mouse model of HCC was established and treated with Cryo, immune checkpoint blockade (ICB), or Cryo + ICB (combination therapy). The growth trend of right untreated tumors and survival time of mice were determined. The expression of apoptosis-related proteins was detected by Western blot (WB) assay. The percentages of immune cells and immunosuppressive cells were analyzed by flow cytometry. The numbers of infiltrating T lymphocytes were checked by immunohistochemistry, and the levels of T-cell-associated cytokines were detected by Quantitative real-time Polymerase Chain Reaction (qRT-PCR) assays and Enzyme-Linked Immunosorbent Assays (ELISA) assays. Results Cryo + ICB inhibited the growth of right untreated tumors, promoted tumor cell apoptosis, and prolonged the survival time of mice. Local T-cell infiltration in right tumor tissues increased after the combination therapy, while the number of immunosuppressive cells was significantly reduced. In addition, the combination therapy may induce the production of multiple Th1-type cytokines but reduce the production of Th2-type cytokines. Conclusions Cryo can activate CD8+ and CD4+ T-cell immune responses. Cryo + ICB can relieve the immunosuppressive tumor microenvironment and shift the Th1/Th2 balance toward Th1 dominance, further enhancing the Cryo-induced T-cell immune response and resulting in a stronger antitumor immune response.

Berberine attenuates 5-fluorouracil-induced intestinal mucosal injury by modulating the gut microbiota without compromising its anti-tumor efficacy

Background5-Fluorouracil (5-Fu), a prominent chemotherapeutic agent for colorectal cancer (CRC) treatment, is often associated with gastrointestinal toxicities, particularly diarrhea. Our previous study demonstrated that berberine (BBR) ameliorates 5-Fu-induced intestinal mucosal injury by modulating the gut microbiota in rats. Nevertheless, the precise molecular mechanism underlying BBR's protective effect on intestinal mucosa remains elusive, and its impact on the anti-tumor efficacy of 5-Fu warrants further investigation. MethodsThe effect of BBR on 5-Fu-induced intestinal mucosal injury was investigated using a tumor-bearing murine model, employing H&E staining, 16S rRNA sequencing, transcriptome sequencing, western blot analysis, cell experiments and constructing a pseudo-germ-free tumor xenograft model. ResultOur findings demonstrate that BBR alleviates intestinal mucosal damage, reduces the levels of inflammatory factors (IL-6, TNF-α, and IL-1β), and inhibits epithelial cell apoptosis in 5-Fu-treated mice without compromising 5-Fu's anti-tumor efficacy. Moreover, 16S rRNA sequencing indicated that BBR significantly increases the abundance of Akkermansia and decreases the abundance of pathogenic bacteria Escherichia/Shigella at the genus level. Mechanistically, transcriptome sequencing and western blot analysis confirmed that BBR upregulates PI3K/AKT/mTOR expression in the intestinal mucosa. However, this effect was not observed in tumor tissues. Notably, BBR did not demonstrate a direct protective effect on 5-Fu-treated CCD841 and SW480 cells. Additionally, BBR had no effect on the PI3K/AKT/mTOR pathway in the intestinal tissue of the 5-Fu-treated mouse model with a depleted gut microbiota. ConclusionThis study indicates that BBR alleviates 5-Fu-induced intestinal mucosal injury by modulating the gut microbiota and regulating the PI3K/AKT/mTOR signaling pathway without compromising the anti-tumor efficacy of 5-Fu.

Two-tailed modification module tuned steric-hindrance effect enabling high therapeutic efficacy of paclitaxel prodrug nanoassemblies

Self-assembled prodrug nanomedicine has emerged as an advanced platform for antitumor therapy, mainly comprise drug modules, response modules and modification modules. However, existing studies usually compare the differences between single types of modification modules, neglecting the impact of steric-hindrance effect caused by chemical structure. Herein, single-tailed modification module with low-steric-hindrance effect and two-tailed modification module with high-steric-hindrance effect were selected to construct paclitaxel prodrugs (P-LAC18 and P-BAC18), and the in-depth insights of the steric-hindrance effect on prodrug nanoassemblies were explored. Notably, the size stability of the two-tailed prodrugs was enhanced due to improved intermolecular interactions and steric hindrance. Single-tailed prodrug nanoassemblies were more susceptible to attack by redox agents, showing faster drug release and stronger antitumor efficacy, but with poorer safety. In contrast, two-tailed prodrug nanoassemblies exhibited significant advantages in terms of pharmacokinetics, tumor accumulation and safety due to the good size stability, thus ensuring equivalent antitumor efficacy at tolerance dose. These findings highlighted the critical role of steric-hindrance effect of the modification module in regulating the structure-activity relationship of prodrug nanoassemblies and proposed new perspectives into the precise design of self-assembled prodrugs for high-performance cancer therapeutics.

Two-tailed modification module tuned steric-hindrance effect enabling high therapeutic efficacy of paclitaxel prodrug nanoassemblies

Self-assembled prodrug nanomedicine has emerged as an advanced platform for antitumor therapy, mainly comprise drug modules, response modules and modification modules. However, existing studies usually compare the differences between single types of modification modules, neglecting the impact of steric-hindrance effect caused by chemical structure. Herein, single-tailed modification module with low-steric-hindrance effect and two-tailed modification module with high-steric-hindrance effect were selected to construct paclitaxel prodrugs (P-LAC18 and P-BAC18), and the in-depth insights of the steric-hindrance effect on prodrug nanoassemblies were explored. Notably, the size stability of the two-tailed prodrugs was enhanced due to improved intermolecular interactions and steric hindrance. Single-tailed prodrug nanoassemblies were more susceptible to attack by redox agents, showing faster drug release and stronger antitumor efficacy, but with poorer safety. In contrast, two-tailed prodrug nanoassemblies exhibited significant advantages in terms of pharmacokinetics, tumor accumulation and safety due to the good size stability, thus ensuring equivalent antitumor efficacy at tolerance dose. These findings highlighted the critical role of steric-hindrance effect of the modification module in regulating the structure-activity relationship of prodrug nanoassemblies and proposed new perspectives into the precise design of self-assembled prodrugs for high-performance cancer therapeutics.

Arsenic Trioxide Suppresses Angiogenesis in Non-small Cell Lung Cancer via the Nrf2-IL-33 Signaling Pathway

Background: Non-Small Cell Lung Cancer (NSCLC) ranks as a leading cause of cancer-related mortality, necessitating the urgent search for cost-effective and efficient anti-NSCLC drugs. Our preliminary research has demonstrated that arsenic trioxide (ATO) significantly inhibits NSCLC angiogenesis, exerting anti-tumor effects. In conjunction with existing literature reports, the Nrf2-IL-33 pathway is emerging as a novel mechanism in NSCLC angiogenesis. Objective: This study aimed to elucidate whether ATO can inhibit NSCLC angiogenesis through the Nrf2-IL-33 pathway. Methods: Immunohistochemistry was employed to assess the expression of Nrf2, IL-33, and CD31 in tumor tissues from patients with NSCLC. DETA-NONOate was used as a nitric oxide (NO) donor to mimic high levels of NO in the tumor microenvironment. Western blot, quantitative real-time PCR, and enzyme-linked immunosorbent assay were utilized to evaluate the expression of Nrf2 and IL-33 in the NCI-H1299 cell line. Subcutaneous xenograft models were established in nude mice by implanting NCI-H1299 cells to assess the anti-tumor efficacy of ATO. Results: High expression levels of Nrf2 and IL-33 were observed in tumor samples from patients with NSCLC, and Nrf2 expression positively correlated with microvascular density in NSCLC. In vitro, NO (released from 1mM DETA-NONOate) promoted activation of the Nrf2-IL-33 signaling pathway in NCI-H1299 cells, which was reversed by ATO. Additionally, both Nrf2 deficiency and ATO treatment significantly attenuated NOinduced IL-33 expression. In vivo, both ATO and the Nrf2 inhibitor ML385 demonstrated significant inhibitory effects on angiogenesis tumor growth. Conclusion: Nrf2-IL-33 signaling is usually activated in NSCLC and positively correlates with tumor angiogenesis. ATO effectively disrupts the activation of the Nrf2-IL-33 pathway in NSCLC and thus inhibits angiogenesis, suggesting its potential as an anti-angiogenic agent for use in the treatment of NSCLC.

In vitro antitumor efficacy of atorvastatin against acute monocytic leukemia cells

In vitro antitumor efficacy of atorvastatin against acute monocytic leukemia cells

PI3K/AKT confers intrinsic and acquired resistance to pirtobrutinib in chronic lymphocytic leukemia

PurposePirtobrutinib, a non-covalent Bruton’s tyrosine kinase (BTK) inhibitor, has been approved as the first agent to overcome resistance to covalent BTK inhibitors (such as ibrutinib, acalabrutinib, and zanubrutinib). However, the mechanisms of pirtobrutinib resistance in chronic lymphocytic leukemia (CLL) remain poorly understood. MethodsTo investigate pirtobrutinib resistance, we established resistant cell models using BTK knock-out via CRISPR-Cas9 or chronic exposure to pirtobrutinib in MEC-1 cells. These models mimicked intrinsic or acquired resistance, respectively. We then analyzed differential protein expression between wild-type (WT) and resistant MEC-1 cells using Revers Phase Protein microArray (RPPA) and confirmed the findings through Western Blot. Additionally, we evaluated potential drugs to overcome pirtobrutinib resistance by conducting cell proliferation assays, apoptosis studies, and animal experiments using both sensitive and resistant cells. ResultsMEC-1 cells developed resistance to pirtobrutinib either through BTK knock-out or prolonged drug exposure over three months. RPPA analysis revealed significant activation of proteins related to the PI3K/AKT pathway, including AKT and S6, in the resistant cells. Western Blot confirmed increased phosphorylation of AKT and S6 in pirtobrutinib-resistant MEC-1 cells. Notably, both the PI3K inhibitor (CAL101) and the AKT inhibitor (MK2206) effectively reduced cell proliferation and induced apoptosis in the resistant cells. The anti-tumor efficacy of these drugs was mediated by inhibiting the PI3K/AKT pathway. In vivo animal studies further supported the potential of targeting PI3K/AKT to overcome both intrinsic and acquired resistance to pirtobrutinib. ConclusionThe PI3K/AKT pathway plays a crucial role in both intrinsic and acquired resistance to pirtobrutinib in CLL. Therapeutically targeting this pathway may offer a promising strategy to overcome pirtobrutinib resistance.

Antitumor efficacy of atorvastatin in lung cancer mice model

Antitumor efficacy of atorvastatin in lung cancer mice model

DOK1 and DOK2 regulate CD8 T cell signaling and memory formation without affecting tumor cell killing

Targeting intracellular inhibiting proteins has been revealed to be a promising strategy to improve CD8+ T cell anti-tumor efficacy. Here, we are focusing on intracellular inhibiting proteins specific to TCR signaling: DOK1 and DOK2 expressed in T cells. We hypothesized that depletion of intracellular inhibition checkpoint DOK1 and DOK2 could improve CD8+ T-cell based cancer therapies. To evaluate the role of DOK1 and DOK2 depletion in physiology and effector function of CD8+ T lymphocytes and in cancer progression, we established a transgenic T cell receptor mouse model specific to melanoma antigen hgp100 (pmel-1 TCR Tg) in WT and Dok1/Dok2 DKO (double KO) mice. We showed that both DOK1 and DOK2 depletion in CD8+ T cells after an in vitro pre-stimulation induced a higher percentage of effector memory T cells as well as an up regulation of TCR signaling cascade- induced by CD3 mAbs, including the increased levels of pAKT and pERK, two major phosphoproteins involved in T cell functions. Interestingly, this improved TCR signaling was not observed in naïve CD8+ T cells. Despite this enhanced TCR signaling essentially shown upon stimulation via CD3 mAbs, pre-stimulated Dok1/Dok2 DKO CD8+ T cells did not show any increase in their activation or cytotoxic capacities against melanoma cell line expressing hgp100 in vitro. Altogether we demonstrate here a novel aspect of the negative regulation by DOK1 and DOK2 proteins in CD8+ T cells. Indeed, our results allow us to conclude that DOK1 and DOK2 have an inhibitory role following long term T cell stimulations.

Construction and performance evaluation of polyguluronic acid polysaccharides-based drug delivery systems

Polysaccharides have garnered significant attention as potential nanoparticle carriers for targeted tumor therapy due to their excellent biodegradability and biocompatibility. Polyguluronic acid (PG) is a homogeneous acidic polysaccharide fragment derived from alginate, which is found in brown algae, possesses excellent bioactivities, unique properties. This study explored the immunomodulatory activity of PG and developed PG-based nanogels through modified disulfide bonds and Ca2+ dual crosslinking. We characterized their structure, assessed their drug-loading and release properties, and ultimately validated both the safety of the nanocarrier and the in vitro anti-tumor efficacy of the encapsulated drug. Results indicated that PG significantly enhanced the proliferative activity and phagocytosis of RAW264.7 cells while promoting reactive oxygen species (ROS) production and cytokine secretion. The study identified TLR4 as the primary receptor for PG recognition in RAW264.7 cells. Furthermore, PG-based drug-carrying nanogels were prepared, exhibiting uniform sizes of about 184nm and demonstrating exceptional encapsulation efficiency (82.15 ± 0.82%) and drug loading capacity (8.12 ± 0.08%). In vitro release experiments showed that these nanogels could responsively release drugs under conditions of high glutathione (GSH) reduction, facilitating drug accumulation at tumor sites and enhancing therapeutic efficacy. This research not only expands the application of PG in drug delivery systems but also provides valuable insights into leveraging natural immunomodulatory polysaccharides as carriers for targeted drug delivery.

Supramolecular assembly of Polydopamine@Fe nanoparticles with near-infrared light-accelerated cascade catalysis applied for synergistic photothermal-enhanced chemodynamic therapy

Chemodynamic therapy (CDT) via Fenton-like reaction is greatly attractive owing to its capability to generate highly cytotoxic •OH radicals from tumoral hydrogen peroxide (H2O2). However, the antitumor efficacy of CDT is often challenged by the relatively low radical generation efficiency and the high levels of antioxidative glutathione in tumor microenvironment. Herein, an innovative photothermal Fenton-like catalyst, Fe-chelated polydopamine (PDA@Fe) nanoparticle, with excellent GSH-depleting capability is constructed via one-step molecular assembly strategy for dual-modal imaging-guided synergetic photothermal-enhanced chemodynamic therapy. Fe(III) ions in PDA@Fe nanoparticles can consume the GSH overexpressed in tumor microenvironment to avoid the potential •OH consumption, while the as-produced Fe(II) ions subsequently convert tumoral H2O2 into cytotoxic •OH radicals through the Fenton reaction. Notably, PDA@Fe nanoparticles demonstrate excellent near-infrared light absorption that results in superior photothermal conversion ability, which further boosts above-mentioned cascade catalysis to yield more •OH radicals for enhanced CDT. Taken together with T1-weighted magnetic resonance imaging (MRI) contrast enhancement (r1 = 8.13 mM−1 s−1) and strong photoacoustic (PA) imaging signal of PDA@Fe nanoparticles, this design finally realizes the synergistic photothermal-chemodynamic therapy. Overall, this work offers a new promising paradigm to effectively accommodate both imaging and therapy functions in one well-defined framework for personalized precision disease treatment.

Mitochondria mediated inhibitory effect of Nyctanthes arbor-tristis (L.) flower extract against breast adenocarcinoma and T-cell lymphoma: An in vitro and in vivo study

Ethnopharmacological relevanceThe flowers of Nyctanthes arbor-tristis (L.) heals mouth ulcers. Its tinctures promote gastric secretions, and improve lung expectoration when taken orally. It has traditionally been used to treats scabies and other skin problems. The leaves of NAT(L.) plant are used in Ayurvedic medicine to treat sciatica, chronic fever, rheumatism, internal worm infections, and as a laxative, diaphoretic, and diuretic. The bark used in treatment of snakebite and bronchitis. In addition to traditional uses, pharmacologically this plant has potent antimalarial, antiarthritic, anticancer and antidiabetic activity. However, the mechanistic antiproliferative potentials of NAT(L.) flower as anticancer therapeutics has not yet been explored. Aim of the studyThe current study is based on a broad range of scientific literature that highlights the nutritional and therapeutic benefits of NAT (L.). Present investigation was carried out to determine the therapeutic efficacy of NAT (L.) against breast adenocarcinoma cells and T-cell lymphoma. Materials and methodsThe ethyl-acetate extract of NAT(L.) was tested against breast cancer cells to assess the anticancer potential. To evaluate apoptosis, intracellular ROS levels and mitochondrial dynamics, fluorescence microscopy and flow cytometry were employed. Additionally, cell cycle analysis and western blotting were also performed. Furthermore, in vivo antitumor efficacy of flower extracts was investigated in T-cell lymphoma-bearing BALB/c mice model. ResultsOur present study revealed that NAT (L.) exert anticancer activity against breast cancer cells effectively at IC50 320 μg/ml while having less impact on normal cells with IC50 more than 480 μg/ml. Fluorescence imaging showed that NAT (L.) treatment elicits a concentration-dependent rise in the occurrence of apoptotic cell deaths with altered mitochondrial dynamics and was subsequently confirmed by flow cytometry. Further, flow cytometric analysis delineates ethyl acetate flower extract exposure promotes arrest of cells in S phase of the cell cycle. The differential expression of apoptotic proteins such as Bax, Bcl-2, cleaved PARP-1, cleaved caspase 3, Cytochrome-c, p53 and VEGF A were influenced by NAT (L.) treatment. The in vivo antitumor activity study delineates that NAT(L.) therapy significantly increased the life span of T-cell lymphoma bearing mice while reducing tumor load and belly size growth pattern without causing significant other distinct side effects as evident by histopathological studies. ConclusionOur current findings unveil that NAT(L.) ethyl acetate flower extract potentially induces mitochondrial pathway of apoptosis, promote cell cycle arrest, reduces tumor load of mice, enhances survivability and could be a promising agent against the triple negative breast cancer and lymphoma.