Extracellular vesicle-mediated communication between CD8+ cytotoxic T cells and tumor cells.

Tumors pose a significant global public health challenge, resulting in numerous fatalities annually. CD8+ T cells play a crucial role in combating tumors; however, their effectiveness is compromised by the tumor itself and the tumor microenvironment (TME), resulting in reduced efficacy of immunotherapy. In this dynamic interplay, extracellular vesicles (EVs) have emerged as pivotal mediators, facilitating direct and indirect communication between tumors and CD8+ T cells. In this article, we provide an overview of how tumor-derived EVs directly regulate CD8+ T cell function by carrying bioactive molecules they carry internally and on their surface. Simultaneously, these EVs modulate the TME, indirectly influencing the efficiency of CD8+ T cell responses. Furthermore, EVs derived from CD8+ T cells exhibit a dual role: they promote tumor immune evasion while also enhancing antitumor activity. Finally, we briefly discuss current prevailing approaches that utilize functionalized EVs based on tumor-targeted therapy and tumor immunotherapy. These approaches aim to present novel perspectives for EV-based tumor treatment strategies, demonstrating potential for advancements in the field.

Strategies to reinvigorate exhausted CD8+ T cells in tumor microenvironment.

CD8+ T cell exhaustion is a stable dysfunctional state driven by chronic antigen stimulation in the tumor microenvironment (TME). Differentiation of exhausted CD8+ T cells (CD8+ TEXs) is accompanied by extensive transcriptional, epigenetic and metabolic reprogramming. CD8+ TEXs are mainly characterized by impaired proliferative and cytotoxic capacity as well as the increased expression of multiple co-inhibitory receptors. Preclinical tumor studies and clinical cohorts have demonstrated that T cell exhaustion is firmly associated with poor clinical outcomes in a variety of cancers. More importantly, CD8+ TEXs are regarded as the main responder to immune checkpoint blockade (ICB). However, to date, a large number of cancer patients have failed to achieve durable responses after ICB. Therefore, improving CD8+ TEXs may be a breakthrough point to reverse the current dilemma of cancer immunotherapy and eliminate cancers. Strategies to reinvigorate CD8+ TEXs in TME mainly include ICB, transcription factor-based therapy, epigenetic therapy, metabolism-based therapy and cytokine therapy, which target on different aspects of exhaustion progression. Each of them has its advantages and application scope. In this review, we mainly focus on the major advances of current strategies to reinvigorate CD8+ TEXs in TME. We summarize their efficacy and mechanisms, identify the promising monotherapy and combined therapy and propose suggestions to enhance the treatment efficacy to significantly boost anti-tumor immunity and achieve better clinical outcomes.

Novel Prognostic Nomogram to Predict Progression-Free Survival of Patients with Hepatocellular Carcinoma After Transarterial Chemoembolization.

Purpose: A retrospective analysis of hepatocellular carcinoma (HCC) patients treated with transarterial chemoembolization (TACE) to identify risk factors was conducted, and a novel predictive nomogram model was constructed. Patients and Methods: A total of 346 HCC patients who underwent TACE as initial treatment were retrospectively included, of which 208 were randomly allocated to the derivation cohort and 138 were allocated to the validation cohort. Progression-free survival (PFS) was used as the follow-up endpoint according to mRECIST. Kaplan‒Meier analysis and the Cox regression model screened out some indicators associated with short-term prognosis, and R language was further used to construct a nomogram model. The nomogram was compared with the classical BCLC staging system. Results: The independent predictors affecting PFS in HCC patients undergoing TACE included the following: 1. Baseline indicators: age (P=0.013), albumin-bilirubin (ALBI) grade (grade 2 vs grade 1, P=0.029; grade 3 vs grade 1, P<0.001), and portal vein tumour thrombus (PVTT, P<0.001); 2. Indicators at the 1-month follow-up: Neutrophil To Lymphocyte Ratio (NLR, P=0.032) and changes in alpha-fetoprotein (AFP, P<0.05) and des-γ-carboxy prothrombin (DCP, P<0.001); and 3. Cumulative treatment numbers of TACE in 6 months (P=0.007). In the derivation cohort, the calibration curve of the nomogram showed a high consistency between the predicted and actual PFS probability, and the nomogram outperformed the BCLC staging system (P=0.004). This result was also confirmed in the validation cohort (P=0.012). Conclusion: The constructed nomogram was suggested to have good predictive efficacy and could be used as a complementary assessment to predict the survival and prognosis of HCC patients treated with TACE.

Efficacy of 125I seed implantation combined with intermittent hormonal therapy on moderate- and high-risk non-metastatic prostate cancer.

PURPOSE: Long non-coding RNA (lncRNA) plasmacytoma variant translocation 1-214 transcript (PVT1-214) is a notable lncRNA involved in gastric cancer and colorectal cancer (CRC) so far. Nowadays, the biological function of PVT1-214 on the response of CRC to chemotherapy is still unclear. We aimed to explore the molecular mechanism of PVT1-214 and its regulatory mechanism in advanced CRC. METHODS: The levels of PVT1-214, microRNA (miR)-128, and interferon regulatory factor-1 (IRF-1) in CRC tissues and cell lines were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). Log-rank test was applied to evaluate the role of high PVT1-214 levels in shortening the overall survival of CRC patients. Chi-square test was to assess the relation between PVT1-214 expression and clinicopathological features of CRC patients. CCK8 assays tested the cell proliferation of oxaliplatin-resistant CRC cells (HCT116/Oxa and SW480/Oxa) with PVT1-214 knockdown. The underlying regulatory mechanism between PVT1-214 and miR-128 was predicted by bioinformatics and verified by RNA transfection, qRT-PCR and western blotting. Chromatin immunoprecipitation (ChIP) assay was done to examine the relationship between or IRF-1 and the PVT1-214 gene. RESULTS: High levels of PVT1-214 expression were more likely to be present in patients with late-stage (IV), chemotherapy resistance, and inferior overall survival. PVT1-214 was aberrantly elevated in oxaliplatin-resistant CRC tissues and cell lines (HCT116/Oxa and SW480/Oxa). PVT1-214 knockdown reduced cell proliferation, migration and invasion of oxaliplatin-resistant CRC cells in vitro. Moreover, IRF-1 was found to be a negative transcription regulator of PVT1-214 and decreased PVT1-214 levels in oxaliplatin-resistant CRC cells. Besides, PVT1-214 repressed miR-128 function by binding to the complementary sites of miR-128. CONCLUSIONS: IRF-1/PVT1-214 may markedly boost the oxaliplatin-resistance of CRC, resulting in the late TNM stage and poor survival. These findings suggest that the IRF-1/PVT1-214 axis may be a helpful target for intervention in CRC.

Actein Inhibits Cell Proliferation and Migration in Human Osteosarcoma.

BACKGROUND Osteosarcoma is one of the most common malignant bone cancers worldwide. Although the traditional chemotherapies have made some progression in the past decades, the mortality of osteosarcoma in children and adolescent is very high. Herein, the role of actein in osteosarcoma was explored. MATERIAL AND METHODS Cell viability assay was performed in osteosarcoma cell lines 143B and U2OS. Colony formation analysis was included when cells were treated with different doses of actin. Cell cycle assay was conducted to further examine the role of actein. Cell apoptotic rate and the relative activities of caspase-3, caspase-8, and caspase-9 were detected in 143B and U2OS osteosarcoma cells. Moreover, transwell assays were used to explore the effects of actein on cell metastasis. RESULTS Actein significantly inhibited osteosarcoma cell viability in a time- and dose-dependent manner. Actein also dramatically suppressed the colony formation ability in osteosarcoma143B and U2OS cells. It was revealed that osteosarcoma cells were arrested in G0/G1 phase in the cell cycle progression and induced to apoptosis by administration of actein. The activities of pro-apoptotic factors such as caspase-3 and caspase-9 were significantly increased by actein. Furthermore, administration of actein decreased cell migrated and invasive abilities in both 143B and U2OS cell lines. CONCLUSIONS Actein inhibits tumor growth by inducing cell apoptosis in osteosarcoma. The inhibitive roles of actein in cell proliferation, migration and invasion suggest that actein may serve as a potential therapeutic agent in the treatment of osteosarcoma.