The year 2024 marks the 60th anniversary of the discovery of the Epstein-Barr virus (EBV), the first virus confirmed to cause human cancer. Viral infections significantly contribute to the global cancer burden, with seven known Group 1 oncogenic viruses, including hepatitis B virus (HBV), human papillomavirus (HPV), EBV, Kaposi sarcoma-associated herpesvirus (KSHV), hepatitis C virus (HCV), human T-cell leukemia virus type 1 (HTLV-1), and human immunodeficiency virus (HIV). These oncogenic viruses induce cellular transformation and cancer development by altering various biological processes within host cells, particularly under immunosuppression or co-carcinogenic exposures. These viruses are primarily associated with hepatocellular carcinoma, gastric cancer, cervical cancer, nasopharyngeal carcinoma, Kaposi sarcoma, lymphoma, and adult T-cell leukemia/lymphoma. Understanding the mechanisms of viral oncogenesis is crucial for identifying and characterizing the early biological processes of virus-related cancers, providing new targets and strategies for treatment or prevention. This review first outlines the global epidemiology of virus-related tumors, milestone events in research, and the process by which oncogenic viruses infect target cells. It then focuses on the molecular mechanisms by which these viruses induce tumors directly or indirectly, including the regulation of oncogenes or tumor suppressor genes, induction of genomic instability, disruption of regular life cycle of cells, immune suppression, chronic inflammation, and inducing angiogenesis. Finally, current therapeutic strategies for virus-related tumors and recent advances in preclinical and clinical research are discussed.

Killer cell lectin-like receptor G1 (KLRG1) is an immune checkpoint receptor expressed predominantly in NK and T-cell subsets that downregulates the activation and proliferation of immune cells and participates in cell-mediated immune responses. Accumulating evidence has demonstrated the importance of KLRG1 as a noteworthy disease marker and therapeutic target that can influence disease onset, progression, and prognosis. Blocking KLRG1 has been shown to effectively mitigate the effects of downregulation in various mouse tumor models, including solid tumors and hematologic malignancies. However, KLRG1 inhibitors have not yet been approved for human use, and the understanding of KLRG1 expression and its mechanism of action in various diseases remains incomplete. In this review, we explore alterations in the distribution, structure, and signaling pathways of KLRG1 in immune cells and summarize its expression patterns and roles in the development and progression of autoimmune diseases, infectious diseases, and cancers. Additionally, we discuss the potential applications of KLRG1 as a tool for tumor immunotherapy.

Acute myeloid leukemia (AML) is characterized by abundant immature myeloid cells, relapse and refractory due to leukemia stem cells (LSCs). Bone marrow mesenchymal stem/ stromal cells (BMSCs) supported LSCs survival, meanwhile, chemotherapy improved connexin43 (CX43) expression. CX43, as the most intercellular gap junction, facilitated transmit mitochondria from BMSCs into AML. We hypothesized that increased mitochondria transferred from BMSCs supported metabolic remodeling in LSCs to sustain their stemness. Primary BMSCs from AML patients were isolated. CX43-BMSCs, overexpressing CX43, were cocultured with KG-1a cells. Fluorescence and confocal microscopy observed mitochondrial transfer. Flow cytometry, EdU assay, and clonogenicity evaluated cell cycle, proliferation, and clonogenic potential. Xenograft mouse models were used to evaluate the tumorigenicity of KG-1a in vivo. Seahorse, RNA-seq, and LC-MS assessed mitochondrial function, transcriptomes, and metabolites post-coculture. CX43-BMSCs promoted unidirectional mitochondrial transfer, enhancing KG-1a adhesion and proliferation to maintain LSCs stemness in vitro and vivo. RNA-seq revealed coculture with CX43-BMSCs upregulated genes related to adhesion, proliferation, and migration in KG-1a cells. Elevated CX43 expression strengthened BMSCs-KG-1a interaction, facilitating mitochondrial transfer and nucleoside metabolism, fueling KG-1a cells. This enhanced mitochondrial energy metabolism, promoting metabolic reprogramming and clonogenicity. CX43-mediated mitochondrial transfer from BMSCs to KG-1a enhances LSCs adhesion, proliferation, clonogenicity, and metabolic reprogramming. CX43 emerges as a potential therapeutic target for AML by sustaining LSCs stemness through metabolic remodeling.

Introduction: Little is known about the first line induction chemotherapy cycles for HIV-associated diffuse large B-cell lymphoma (DLBCL) as these are less common than HIV-negative lymphoma. Currently, the optimal treatment cycles option remains undefined. Therefore, we performed a multi-center study to analyze the clinical characteristics and outcomes of HIV-associated DLBCL patients in different treatment modes in China.Methods: Totally 273 newly diagnosed HIV-associated DLBCL patients at eleven large academic centers from October 2008 to October 2021, were analyzed.Results: In the entire cohort, the median age was 47 years (range, 21-90) at lymphoma diagnosis, and 223 patients were male (81.7%). One hundred and ninety-four (71.1%) patients were germinal center B-cell-like lymphoma (GCB) subtype. Most patients (65.2%, 178/273) had elevated lactate dehydrogenase (LDH), and advanced Ann Arbor stage (78.9% 213/273) at diagnosis. High international prognostic index (IPI) score (3-5) at diagnosis was found in 65.2% (178/273) of patients. One hundred and fifty-five patients (56.8%) had extranodal involvement. The median CD4 cell count was 168/μl (range, 2-1067), of whom 174 (63.7%) had a CD4 cell count below 200/μl. The median follow‐up of our cohort was 10.1 (0.1-160) months. The overall 2-year OS rates 58.0%. Median OS times in the 0, 1-3, 4-6, and >6 cycles chemotherapy cohort were 7.1 months, 20.0 months, not reached, and not reached, respectively (Hazard Ratio (HR)=0.549, 95% Confidence interval (CI) 0.451-0.667; p6 cycles chemotherapy did not further improve the survival of patients.

Haematological malignancies are one of the most common tumors, with a rising incidence noted over recent decades. Viral infections play significant roles in the pathogenesis of these malignancies globally. This review delves into the contributions of various known viruses—specifically Epstein-Barr virus (EBV), human immunodeficiency virus (HIV), human T-cell leukemia virus type 1 (HTLV-1), Kaposi’s sarcoma-associated herpesvirus (KSHV), human cytomegalovirus (HCMV), hepatitis B virus (HBV), hepatitis C virus (HCV), and human papillomavirus (HPV)—in the development of haematological malignancies. These viruses are shown to drive tumorigenesis through mechanisms, such as metabolic reprogramming, epigenetic modifications, and remodeling of the immune microenvironment. By directly disrupting fundamental cellular functions and altering metabolic and epigenetic pathways, these viruses foster an immune milieu that supports both viral persistence and tumor growth. A thorough understanding of these viral oncogenic processes is crucial not only for etiological discovery but also for developing targeted interventions. This review emphasizes the need for continued research into the specific ways these viruses manipulate the host cell’s metabolic and epigenetic environments, aiming to provide insights that could guide future advancements in treatment modalities.

Little is known about the incidence, clinical characteristics and prognostic factors in HIV associated lymphoma as these are less common than HIV‐negative lymphoma in China. Currently, there are no standard guidelines for treatment of these patients. Therefore, we performed a study to analyse the clinical characteristics and outcomes of newly diagnosed HIV‐associated aggressive B‐cell non‐Hodgkin's lymphoma (NHL) patients in Chongqing University Cancer Hospital (CUCH). Totally 86 newly diagnosed HIV‐associated aggressive B‐cell NHL patients in CUCH, southwest China, from July 2008 to August 2021, were analysed. In the entire cohort, median age was 48 years (range, 23–87 years), and more patients were male (87.2%). Most patients had elevated lactate dehydrogenase (LDH) (82.6%), advanced ann arbor stage (80.2%) and high IPI score (IPI score, 3–5) (62.7%) at diagnosis. Median CD4+ T‐cell count at diagnosis was 191/μl (range, 4–1022), 84 patients (97.7%) were on combination antiretroviral therapy (cART) at lymphoma diagnosis. In DLBCL patients, cox multivariate analysis showed that age ≥ 60 (HR = 2.251, 95%CI 1.122–4.516; p = 0.012), elevated LDH (HR = 4.452, 95%CI 1.027–19.297; p = 0.041) and received less than two cycles of chemotherapy (HR = 0.629, 95%CI 0.589–1.071; p = 0.012) were independent risk factors for adverse prognosis based on PFS. Age ≥ 60 (HR = 3.162, 95%CI 1.500–6.665; p = 0.002) and received less than two cycles of chemotherapy (HR = 0.524, 95%CI 0.347–0.791; p = 0.002) were also independent risk factor for adverse prognosis based on OS. In BL patients, cox multivariate analysis showed that elevated LDH and received less than two cycles of chemotherapy were independent risk factors for adverse prognosis. In the DLBCL group, median PFS times in the received rituximab and no received rituximab groups were not reached and 12 months, respectively (p = 0.006). Median OS times were not reached and 36 months, respectively (p = 0.021). In the BL group, median PFS times in the received rituximab and no received rituximab groups were not reached and 4.8 months, respectively (p = 0.046). Median OS times were not reached and 10.1 months, respectively (p = 0.035). Overall, these data indicated that standardized anti‐lymphoma therapy and rituximab administration were significantly associated with improved outcomes in patients with HIV‐associated DLBCL and BL.