Cellular Oncology最新文献

Background: Potassium channel tetramerization domain-containing 1 (KCTD1) plays a critical role in transcriptional regulation and adipogenesis, but its significance in hepatocellular cancer (HCC) has not been reported.

Methods: Immunohistochemistry, Western blotting and quantitative real-time PCR analysis were performed to assess the expression of KCTD1 and related genes in HCC cells. MTT assays, colony formation, cell migration, invasion and the in-vivo mouse models were utilized to evaluate the function of KCTD1 in HCC progression. Co-immunoprecipitation, chromatin immunoprecipitation and luciferase reporter assays were conducted to elucidate the molecular mechanisms of KCTD1 in HCC.

Results: KCTD1 expression was increased in human HCC tissues and closely associated with advanced tumor stages. KCTD1 overexpression enhanced growth, migration, and invasion of Huh7 and HepG2 cells both in vitro and in vivo, while KCTD1 knockdown reversed these effects in MHCC97H cells. Mechanistically, KCTD1 interacted with hypoxia-inducible factor 1 alpha (HIF-1α) and enhanced HIF-1α protein stability with the inhibited prolyl-hydroxylases (PHD)/Von Hippel-Lindau (VHL) pathway, consequently activating the Vascular Endothelial Growth Factor (VEGF)/VEGFR2 pathway in HCC cells. Sorafenib and KCTD1 knockdown synergistically inhibited intrahepatic tumor growth following in situ injection of MHCC97H cells. miR-129-5p downregulated KCTD1 by binding to KCTD1 3'UTR. Finally, 45 µg exosomes from miR-129-5p-overexpressing MHCC97H cells combined with 25 mg/kg sorafenib to decrease HCC tumor size.

Conclusions: These results suggested that KCTD1 protects HIF-1α from degradation and activates the VEGF signaling cascade to enhance HCC progression. Therefore, KCTD1 may serve as a novel target of HCC and pave the way for an efficient combined therapy in advanced HCC.

Purpose: The Hippo pathway in the tumorigenesis and progression of PDAC, with lysophosphatidic acid (LPA) regulating the Hippo pathway to facilitate cancer progression. However, the impact of the Hippo signaling pathway on tumor repopulation in PDAC remains unreported.

Methods: Direct and indirect co-culture models to investigate gemcitabine-induced apoptotic cells can facilitate the repopulation of residual tumor cells. Mass spectrometry analysis was conducted to assess the impact of gemcitabine treatment on the lipid metabolism of pancreatic cancer cells. ELISA assays confirmed gemcitabine promotes the release of LPA from apoptotic pancreatic cancer cells. The expression of Yes-associated protein 1 (YAP1) elucidated the underlying mechanism by which dying cells induce tumor repopulation using qRT-PCR and Western blot. We studied the biological function of pancreatic cancer cells using CCK-8, colony formation, and transwell invasion assays in vitro. Co-culture models were used to validate the impact of Hippo pathway on tumor repopulation, while flow cytometry was employed to assess the sensitivity of pancreatic cancer cells to gemcitabine in the context of Hippo pathway.

Results: Gemcitabine-induced dying cells released LPA in a dose-dependent manner, which promoted the proliferation, clonal formation, and invasion of pancreatic cancer cells. Mechanistic studies showed that gemcitabine and LPA facilitated the translocation of YAP1 and induced the inactivation of the Hippo pathway. YAP1 overexpression significantly enhanced the activity of autotaxin, leading to stimulated pancreatic cancer cells to secrete LPA. This mechanism orchestrated a self-sustaining LPA-Hippo feedback loop, which drove the repopulation of residual tumor cells. Simultaneously, it was observed that suppressing LPA and YAP1 expression enhanced the sensitivity of pancreatic cancer cells to gemcitabine.

Conclusion: Our investigation indicated that targeting the LPA-YAP1 signaling pathway could serve as a promising strategy to augment the overall therapeutic efficacy against PDAC.

Introduction: Tertiary lymphoid structures (TLS) are lymphocyte aggregates resembling secondary lymphoid organs and are pivotal in cancer immunity. The ambiguous morphological definition of TLS makes it challenging to ascertain their clinical impact on patient survival and response to immunotherapy.

Objectives: This study aimed to characterize TLS in hematoxylin-eosin tissue sections from lung cancer patients, assessing their occurrence in relation to the local immune environment, mutational background, and patient outcome.

Methods: Two pathologists evaluated one whole tissue section from resection specimens of 680 NSCLC patients. TLS were spatially quantified within the tumor area or periphery and further categorized based on the presence of germinal centers (mature TLS). Metrics were integrated with immune cell counts, genomic and transcriptomic data, and correlated with clinical parameters.

Results: TLS were present in 86% of 536 evaluable cases, predominantly in the tumor periphery, with a median of eight TLS per case. Mature TLS were found in 24% of cases. TLS presence correlated positively with increased plasma cell (CD138+) and lymphocytic cell (CD3+, CD8+, FOXP3+) infiltration. Tumors with higher tumor mutational burden exhibited higher numbers of peripheral TLS. The overall TLS quantity was independently associated with improved patient survival, irrespective of TLS maturation status. This prognostic association held true for peripheral TLS but not for tumor TLS.

Conclusion: TLS in NSCLC is common and their correlation with a specific immune phenotype suggests biological relevance in the local immune reaction. The prognostic significance of this scoring system on routine hematoxylin-eosin sections has the potential to augment diagnostic algorithms for NSCLC patients.

Purpose: Malignant melanoma is the deadliest skin cancer, with a poor prognosis in advanced stages. We reported that both Hedgehog-GLI (HH/GLI) and Mitogen-activated protein Kinase (MAPK) extracellular signal-regulated kinase 5 (ERK5) pathways promote melanoma growth, and that ERK5 activation is required for HH/GLI-dependent melanoma cell proliferation. Here, we explored whether ERK5 regulates HH/GLI signaling.

Methods: Both genetic (using ERK5-specific shRNA) and pharmacologic (using the ERK5 inhibitors JWG-071 and AX15836, and the MAPK/ERK kinase 5, MEK5 inhibitors GW284543 and BIX02189) targeting approaches were used. Luciferase assay using the GLI-binding site luciferase reporter was performed to evaluate GLI transcriptional activity. A constitutively active form of MEK5 (MEK5DD) was used to induce ERK5 activation. 3D spheroid assays were performed in melanoma cells.

Results: Genetic and pharmacologic ERK5 inhibition reduces GLI1 and GLI2 protein levels and transcriptional activity of endogenous HH/GLI pathway induced by the agonist SAG in NIH/3T3 cells. In these cells, MEK5DD overexpression potentiates transcriptional activity of endogenous HH/GLI pathway induced by SAG, whereas ERK5 silencing prevents this effect. Consistently, MEK5DD overexpression increases GLI1 and GLI2 protein levels. In melanoma cells, ERK5 silencing reduces GLI1 and GLI2 mRNA and protein levels and inhibits GLI transcriptional activity. MEK5DD further increases the transcriptional activity of the HH/GLI pathway and GLI1 protein levels. Combination of GLI and MEK5 inhibitors is more effective than single treatments in reducing melanoma spheroid growth.

Conclusions: MEK5-ERK5 is an activator of GLI transcription factors, and combined targeting of these pathways warrants further preclinical investigation as a potential innovative therapeutic approach for melanoma.

Hypoxia is a critical microenvironmental condition that plays a major role in driving tumorigenesis and cancer progression. Increasing evidence has revealed novel functions of hypoxia in intercellular communication. The hypoxia induced tumor derived exosomes (hiTDExs) released in high quantities by tumor cells under hypoxia are packed with unique cargoes that are essential for cancer cells' interactions within their microenvironment. These hiTDExs facilitate not only immune evasion but also promote cancer cell growth, survival, angiogenesis, EMT, resistance to therapy, and the metastatic spread of the disease. Nevertheless, direct interventions targeting hypoxia signaling in cancer therapy face challenges related to tumor progression and resistance, limiting their clinical effectiveness. Therefore, deepening our understanding of the molecular processes through which hiTDExs remodels tumors and their microenvironment, as well as how tumor cells adjust to hypoxic conditions, remains essential. This knowledge will pave the way for novel approaches in treating hypoxic tumors. In this review, we discuss recent work revealing the hiTDExs mediated interactions between tumor and its microenvironment. We have described key hiTDExs cargos (lncRNA, circRNAs, cytokines, etc.) and their targets in the receipt cells, responsible for various biological effects. Moreover, we emphasized the importance of hiTDExs as versatile elements of cell communication in the tumor microenvironment. Finally, we highlighted the effects of hiTDExs on the molecular changes in target cells by executing molecular cargo transfer between cells and altering signaling pathways. Currently, hiTDExs show promise in the treatment of diseases. Understanding the molecular processes through which hiTDExs influence tumor behavior and their microenvironment, along with how tumor cells adapt to and survive in low-oxygen conditions, remains a central focus in cancer research, paving the way for innovative strategies in treating hypoxic tumors and enhancing immunotherapy.

Purpose: Central nervous system (CNS) involvement and/or relapse remains one of the most important causes of morbidity/mortality in paediatric B-cell precursor acute lymphoblastic leukaemia (BCP-ALL) patients. To identify novel therapeutic targets and develop less aggressive therapies, a better understanding of the cellular and molecular microenvironment in leptomeningeal metastases is key. Here, we aimed to investigate the formation of metastatic leptomeningeal aggregates and their relevance to the expansion, survival and chemoresistance acquisition of leukaemia cells.

Methods: We used BCP-ALL xenograft mouse models, combined with immunohistofluorescence and flow cytometry, to study the development of CNS metastasis and the contribution of leptomeningeal cells to the organisation of leukaemic aggregates. To in vitro mimic the CNS metastasis, we established co-cultures of three-dimensional (3D) ALL cell spheroids and human leptomeningeal cells (hLMCs) and studied the effects on gene expression, proliferation, cytokine production, and chemoresistance.

Results: In xenografted mice, ALL cells infiltrated the CNS at an early stage and, after crossing an ER-TR7⁺ fibroblast-like meningeal cell layer, they proliferated extensively and formed large vascularised leukaemic aggregates supported by a network of podoplanin⁺ leptomeningeal cells. In leukaemia spheroid-hLMC co-cultures, unlike conventional 2D co-cultures, meningeal cells strongly promoted the proliferation of leukaemic cells and generated a pro-inflammatory microenvironment. Furthermore, in 3D cell aggregates, leukaemic cells also developed chemoresistance, at least in part due to ABC transporter up-regulation.

Conclusion: Our results provide evidence for the formation of metastatic ALL-leptomeningeal cell aggregates, their pro-inflammatory profile and their contribution to leukaemic cell expansion, survival and chemoresistance in the CNS.

Introduction: Germline CDKN2A variant predisposes to childhood acute lymphoblastic leukemia (ALL) through allelic expression imbalance (AEI). It is unknown, therefore, how these germline variations work and whether they all confer B-ALL susceptibility through AEI.

Methods and results: Using allele-specific Taqman PCR assays, we demonstrated that preferentially expressed of those functional inherited coding variants in leukemic cells compared to hematopoietic cells. In an inherent p 16^Ink4a-defective Ba/F3 cell model overexpressing functional p16^INK4A variants showed enhanced susceptibility to transformation by BCR-ABL1-, NRAS^G12D-, and JAK2^R683G + CRLF2-. Notably, the variant p16^INK4A exhibited higher transcription level than wild-type allele in co-expression studies. While CDK4/6 inhibitor partially suppressed NRAS^G12D-, and JAK2^R683G + CRLF2-induced transformation, it proved ineffective against BCR-ABL1-induced leukemic transformation. Differential gene expression analysis revealed upregulation of m6A-related gene PRRC2A, whose knockout partially restored wild-type p16^INK4A expression.

Conclusion: These findings illuminate how inherited CDKN2A genetic variations of coding region influence ALL development through AEI mechanisms.

Tumor-infiltrating myeloid cells (TIMs), which encompass tumor-associated macrophages (TAMs), tumor-associated neutrophils (TANs), myeloid-derived suppressor cells (MDSCs), and tumor-associated dendritic cells (TADCs), are of great importance in tumor microenvironment (TME) and are integral to both pro- and anti-tumor immunity. Nevertheless, the phenotypic heterogeneity and functional plasticity of TIMs have posed challenges in fully understanding their complexity roles within the TME. Emerging evidence suggested that the presence of TIMs is frequently linked to prevention of cancer treatment and improvement of patient outcomes and survival. Given their pivotal function in the TME, TIMs have recently been recognized as critical targets for therapeutic approaches aimed at augmenting immunostimulatory myeloid cell populations while depleting or modifying those that are immunosuppressive. This review will explore the important properties of TIMs related to immunity, angiogenesis, and metastasis. We will also document the latest therapeutic strategies targeting TIMs in preclinical and clinical settings. Our objective is to illustrate the potential of TIMs as immunological targets that may improve the outcomes of existing cancer treatments.

Background: Adoptive cell therapy (ACT) mediates durable and complete regression of various cancers. However, its efficacy is limited by the long-term persistence of cytotoxic T lymphocytes, given their irreversible dysfunction within the tumor microenvironment. Herein, we aimed to establish an artificial lung metastasis model to examine T-lymphocyte subsets, in order to identify potential effective cell subsets for ACT.

Methods: A metastatic lung melanoma mouse model was established using OVA-expressing melanoma B16 cells. Flow cytometry analysis was conducted to examine the surface markers, transcription factors, and secreted cytokines of tumor-specific CD8⁺ T cells within metastatic tissues. The infiltrated cells were sorted by flow cytometry for in vitro tumor cell killing assays or in vivo cell infusion therapy combined with chemotherapeutic drugs and immune checkpoint blockade antibodies.

Results: Exhausted CD8⁺ T cells (Tex) exhibited high heterogeneity in metastatic tissues. Among Tex cells, the CXCR6^- precursor cell showed certain memory characteristics, including phenotype, transcription factors, and maintenance, whereas the CXCR6⁺ subpopulation partially lost these traits. Moreover, CXCR6⁺ precursor cells effectively replenished effector-like Tex cells in metastatic tissues and exerted direct cytotoxicity against tumor cells. Notably, transferring these tumor-specific CXCR6⁺ precursor-exhausted T (Texp) cells into recipients induced a substantial regression of metastasis. In addition, these cells could respond to immune checkpoint blockade, which could better control tumor metastasis.

Conclusions: In our study, a subset of antigen-specific CXCR6-expressing Texp cells was observed within the metastatic tissue. The cells served as a crucial source of effector-like Tex cells and exerted direct cytotoxic effects on tumor cells. Adoptive transfer of CXCR6⁺ Texp cells effectively mitigated lung metastasis in mice. This study helps elucidate the role of Texp cells in metastasis, thereby offering novel insights into enhancing the efficacy and durability of immunotherapy.

Cell senescence is a natural response within our organisms. Initially, it was considered an effective anti-tumor mechanism. However, it is now believed that while cell senescence initially acts as a robust barrier against tumor initiation, the subsequent accumulation of senescent cells can paradoxically promote cancer recurrence and cause damage to neighboring tissues. This intricate balance between cell proliferation and senescence plays a pivotal role in maintaining tissue homeostasis. Moreover, senescence cells secrete many bioactive molecules collectively termed the senescence-associated secretory phenotype (SASP), which can induce chronic inflammation, alter tissue architecture, and promote tumorigenesis through paracrine signaling. Among the myriads of compounds, senotherapeutic drugs have emerged as exceptionally promising candidates in anticancer treatment. Their ability to selectively target senescent cells while sparing healthy tissues represents a paradigm shift in therapeutic intervention, offering new avenues for personalized oncology medicine. Senolytics have introduced new therapeutic possibilities by enabling the targeted removal of senescent cells. As standalone agents, they can clear tumor cells in a senescent state and, when combined with chemo- or radiotherapy, eliminate residual senescent cancer cells after treatment. This dual approach allows for the intentional use of lower-dose therapies or the removal of unintended senescent cells post-treatment. Additionally, by targeting non-cancerous senescent cells, senolytics may help reduce tumor formation risk, limit recurrence, and slow disease progression. This article examines the mechanisms of cellular senescence, its role in cancer treatment, and the importance of senotherapy, with particular attention to the therapeutic potential of senolytic drugs.