Altered HLA-A2-restricted TP53 epitope induces specific CTL cytotoxicity against hepatocellular carcinoma.

High-frequency mutation of the TP53 tumor suppressor gene is observed in multiple human cancers, which promotes cancer progression. However, the mutated gene-encoded protein may serve as a tumor antigen to elicit tumor-specific immune responses. In this study, we detected widespread expression of shared TP53-Y220C neoantigen in hepatocellular carcinoma with low affinity and low stability of binding to HLA-A0201 molecules. We substituted the amino acid sequences VVPCEPPEV with VLPCEPPEV in the TP53-Y220C neoantigen to yield a TP53-Y220C (L2) neoantigen. This altered neoantigen was found to increase affinity and stability and induce more cytotoxic T lymphocytes (CTLs), indicating improvements in immunogenicity. In vitro assays showed the cytotoxicity of CTLs stimulated by both TP53-Y220C and TP53-Y220C (L2) neoantigens against multiple HLA-A0201-positive cancer cells expressing TP53-Y220C neoantigens; however, the TP53-Y220C (L2) neoantigen showed higher cytotoxicity than the TP53-Y220C neoantigen against cancer cells. More importantly, in vivo assays demonstrated greater inhibition of hepatocellular carcinoma cell proliferation by TP53-Y220C (L2) neoantigen-specific CTLs relative to TP53-Y220C neoantigen in zebrafish and nonobese diabetic/severe combined immune deficiency mouse models. The results of this study demonstrate enhanced immunogenicity of the shared TP53-Y220C (L2) neoantigen, which has the potential as dendritic cells or peptide vaccines for multiple cancers.

EIF3B affects the invasion and metastasis of hepatocellular carcinoma cells via the TGFBI/MAPK/ERK pathway.

INTRODUCTION AND OBJECTIVES: To study the effect of eukaryotic initiation factor 3B (EIF3B) on the invasion and migration of hepatocellular carcinoma (HCC) and its potential mechanism. MATERIALS AND METHODS: The clinical significance of EIF3B expression was studied with The Cancer Genome Atlas (TCGA) and Gene Expression Profiling Interaction Analysis datasets. Immunohistochemical staining and western blotting were used to examine EIF3B expression in cell lines and tissues from HCC patients. The scratch assay and transwell assay were used to measure the invasion and metastasis of different HCC cell lines in vitro. The molecular mechanism of EIF3B was determined using RNA-seq and identification of dysregulated signaling pathways. Western blotting was used to verify the alterations of EIF3B signaling functioned in the promotion of HCC progression. RESULTS: Elevated expression of EIF3B in HCC correlated significantly with aggressive clinicopathologic characteristics, including advanced tumor grade and poor prognosis. Studies with cultured cells indicated that EIF3B knockdown inhibited HCC cell invasion and metastasis by depressing the epithelial-mesenchymal transition (EMT). EIF3B also activated the TGFBI/MAPK/ERK signaling pathway by increasing the levels of pMEK and pERK. CONCLUSIONS: Our results indicate that EIF3B functions as an oncogene in HCC that accelerates cell invasion, metastasis, and the EMT by stimulation of the TGFBI/MAPK/ERK signaling pathway. EIF3B is a potential target for the treatment of HCC.

A positive feedback loop between ID3 and PPARγ via DNA damage repair regulates the efficacy of radiotherapy for rectal cancer.

OBJECTIVE: To study the effect of inhibitor of differentiation 3 (ID3) on radiotherapy in patients with rectal cancer and to explore its primary mechanism. METHODS: Cell proliferation and clonogenic assays were used to study the relationship between ID3 and radiosensitivity. Co-immunoprecipitation and immunofluorescence were performed to analyze the possible mechanism of ID3 in the radiosensitivity of colorectal cancer. At the same time, a xenograft tumor model of HCT116 cells in nude mice was established to study the effect of irradiation on the tumorigenesis of ID3 knockdown colorectal cancer cells in vivo. Immunohistochemistry was performed to analyze the relationship between ID3 expression and the efficacy of radiotherapy in 46 patients with rectal cancer. RESULTS: Proliferation and clonogenic assays revealed that the radiosensitivity of colorectal cancer cells decreased with ID3 depletion through p53-independent pathway. With the decrease in ID3 expression, MDC1 was downregulated. Furthermore, the expression of ID3, MDC1, and γH2AX increased and formed foci after irradiation. ID3 interacted with PPARγ and form a positive feedback loop to enhance the effect of ID3 on the radiosensitivity of colorectal cancer. Irradiation tests in nude mice also confirmed that HCT116 cells with ID3 knockdown were more affected by irradiation. Immunohistochemical study showed that rectal cancer patients with low expression of ID3 had better radiotherapy efficacy. CONCLUSIONS: ID3 and PPARγ influence the radiosensitivity of colorectal cancer cells by interacting with MDC1 to form a positive feedback loop that promotes DNA damage repair. Patients with low expression of ID3 who received neoadjuvant chemoradiotherapy can obtain a better curative effect.

RNF38 suppress growth and metastasis via ubiquitination of ACTN4 in nasopharyngeal carcinoma.

BACKGROUND: Accumulated evidence suggests that RING finger proteins (RNFs) are involved in the carcinogenesis of cancers. However, RNF38, a member of the RNF protein family, has not been studied in nasopharyngeal carcinoma (NPC). METHODS: RNF38 expression was analyzed by RT-PCR, Western blotting and Immunohistochemistry. Biological functions of RNF38 were evaluated by cell growth, colony formation, apoptosis, migration and invasion assays in vitro. Xenograft growth and lung metastasis models were conducted to investigate the effect of RNF38 in vivo. Liquid chromatography coupled with tandem mass spectrometry, co-immunoprecipitation, and CHX assay were implemented to detect the interaction among RNF38 and ACTN4. RESULTS: RNF38 was significantly downregulated in NPC cells and tissues. Immunohistochemistry implied that loss of RNF38 was an independent prognostic factor for poor outcomes of NPC patients. Gain- and loss-of-function experiments showed that RNF38 inhibited proliferation and metastasis in NPC in vitro and in vivo. Upregulation of RNF38 promoted apoptosis of NPC cells to etoposide but not cisplatin. ACTN4 was upregulated in NPC and negatively correlated with RNF38. Mechanistic investigations suggested that RNF38 inactivates the NF-𝛋B and ERK1/2 signaling pathways by inducing ubiquitination and degradation of ACTN4. RNF38 suppress the development of NPC by interacting with ACTN4. CONCLUSIONS: RNF38 plays a potential cancer suppressor gene role in NPC tumorigenesis and is a prognostic biomarker in NPC.

An altered HLA-A0201-restricted MUC1 epitope that could induce more efficient anti-tumor effects against gastric cancer.

MUC1 is a tumor-associated antigen (TAA) overexpressed in many tumor types, which makes it an attractive target for cancer immunotherapy. However, this marker is a non-mutated antigen without high immunogenicity. In this study, we designed several new altered peptides by replacing amino acids in their sequences, which were derived from a low-affinity MUC1 peptide, thus bypassing immune tolerance. Compared to the wild-type (WT) peptide, the altered MUC1 peptides (MUC11081-1089L2, MUC11156-1164L2, MUC11068-1076Y1) showed higher affinity to the HLA-A0201 molecule and stronger immunogenicity. Furthermore, these altered peptides resulted in the generation of more cytotoxic T lymphocytes (CTLs) that could cross-recognize gastric cancer cells expressing WT MUC1 peptides, in an HLA-A0201-restricted manner. In addition, M1.1 (MUC1950-958), a promising antitumor peptide that has been tested in multiple tumors, was not able to induce stronger antitumor responses. Collectively, our results demonstrated that altered peptides from MUC1, as potential HLA-A0201-restricted CTL epitopes, could serve as peptide vaccines or constitute components of peptide-loaded dendritic cell vaccines for gastric cancer treatment.

Multiscale network analysis reveals molecular mechanisms and key regulators of the tumor microenvironment in gastric cancer.

Gastric cancer (GC) is the third leading cause of cancer deaths and the fourth most prevalent malignancy worldwide. The high incidence and mortality rates of gastric cancer result from multiple factors such as ineffective screening, diagnosis, and limited treatment options. In our study, we sought to systematically identify predictive molecular networks and key regulators to elucidate complex interacting signaling pathways in GC. We performed an integrative network analysis of the transcriptomic data in The Cancer Genome Atlas (TCGA) gastric cancer cohort and then comprehensively characterized the predictive subnetworks and key regulators by the matched genetic and epigenetic data. We identified 221 gene subnetworks (modules) in GC. The most prognostic subnetworks captured multiple aspects of the tumor microenvironment in GC involving interactions among stromal, epithelial and immune cells. We revealed the genetic and epigenetic underpinnings of those subnetworks and their key transcriptional regulators. We computationally predicted and experimentally validated specific mechanisms of anticancer effects of GKN2 in gastric cancer proliferation and invasion in vitro. The network models and the key regulators of the tumor microenvironment in GC identified here pave a way for developing novel therapeutic strategies for GC.

Circulating Epstein-Barr virus microRNAs BART7-3p and BART13-3p as novel biomarkers in nasopharyngeal carcinoma.

Epstein-Barr virus (EBV) BamHI A rightward transcripts (BART) encoded microRNAs (EBV-miR-BARTs) are abnormally highly expressed in nasopharyngeal carcinoma (NPC). This study aims to investigate the diagnostic and prognostic performance of miR-BART7-3p and miR-BART13-3p. Plasma levels of EBV DNA, miR-BART7-3p, and miR-BART13-3p were examined by quantitative PCR in 483 treatment-naïve NPC patients and 243 controls without NPC. The prognostic performance was examined by comparing plasma levels with rates of distant metastasis during follow-up. The area under the receiver operating characteristic curve for diagnosing NPC was 0.926 for EBV DNA, 0.964 for plasma miR-BART7-3p, 0.973 for miR-BART13-3p, and 0.997 for all three indices. Among 465 NPC patients without distant metastasis, the above-median miR-BART7-3p and EBV DNA were independent risk for shorter distant metastasis-free survival (DMFS) (hazard ratio [HR] = 2.94, 95% confidence interval [CI], 1.44-5.97, P = .003; HR = 2.27, 95% CI, 1.26-4.10, P = .006) in multivariate Cox regression. Epstein-Barr virus DNA, miR-BART7-3p, and miR-BART13-3p after radiotherapy were detectable in 28.6%, 17.6%, and 54.7% of patients, respectively. In multivariate Cox regression, detectable miR-BART7-3p and EBV DNA were independent risks for shorter DMFS (HR = 4.13, 95% CI, 1.89-9.01, P < .001; HR = 2.14, 95% CI, 1.04-4.42, P = .039). The 4-year DMFS rate was 92.0% in subjects (n = 156) with neither detectable miR-BART7-3p nor EBV DNA, 80.0% in subjects (n = 65) with either detectable miR-BART7-3p or EBV DNA, and 52.9% in subjects (n = 24) with both detectable miR-BART7-3p and EBV DNA after radiotherapy (P < .001). Circulating levels of miR-BART7-3p and miR-BART13-3p show excellent diagnostic performance for NPC. The combination of plasma levels of miR-BART7-3p and EBV DNA at diagnosis and after radiotherapy could help stratify patients by risk of poor DMFS.

Dual-target IL-12-containing nanoparticles enhance T cell functions for cancer immunotherapy.

Cytotoxic T lymphocytes (CTLs) play a major role in cancer immunotherapy. A potent tumor immunotherapy may not only require activation of anti-tumor effector cells but also rely on the use of cytokines to create a controlled environment for the development of anti-tumor T cells. In this study, we fabricated a dual-target immunonanoparticle, e.g. poly(d,l-lactide-co-glycolide) nanoparticle, by loading Interleukin-12 (IL-12) and modifying with CD8 and Glypican-3 antibodies on the surface. Our results demonstrate that the fabricated targeting immunonanoparticles bind specifically to the two target cells of interest, i.e. CD8+ T cells and HepG-2 cells via the antibody-antigen interactions and form T cell-HepG-2 cell clusters, which enhances the cytotoxicity of T cells. IL-12-containing dual-target immunonanoparticles delivered IL-12 specifically to CD8+ T cells, and favored the expansion, activation and cytotoxic activity of CD8+ T lymphocytes. These results suggest that dual-target IL-12-encapsulated nanoparticles are a promising platform for cancer immunotherapy.

A kinase-interacting protein 1 may serve as a potential biomarker for deteriorative tumor features and poor prognosis in gastric cancer patients.

OBJECTIVE: This study aimed to explore the association of A kinase-interacting protein 1 (AKIP1) expression with clinicopathological characteristics and prognosis in gastric cancer patients. METHODS: Data of 260 gastric cancer patients were retrospectively reviewed. AKIP1 expression in tumor tissue and non-cancerous tissue specimens was detected by immunohistochemistry and semi-quantitatively scored according to the staining intensity and density. Moreover, the clinicopathological features were retrieved, and disease-free survival (DFS) and overall survival (OS) were calculated. RESULTS: A kinase-interacting protein 1 expression was increased in tumor tissues compared with non-cancerous tissues (P < .001). In terms of tumor features, tumor AKIP1 high expression correlated with elevated T stage (P < .001) and raised TNM stage (P = .042), while did not correlate with pathological grade (P > .999), tumor size (P = .060), N stage (P = .180), or tumor location (P > .999). Meanwhile, tumor AKIP1 was not associated with the non-tumor features either. Kaplan-Meier curves disclosed that AKIP1 high expression patients had shorter DFS (P = .004) and OS (P = .043) compared with AKIP1 low expression patients. Univariate Cox's regression showed that AKIP1 high expression correlated with shorter DFS (P = .005, hazard ratio [HR] = 1.635) and OS (P = .046, HR = 1.519), whereas multivariate Cox's regression displayed that AKIP1 did not independently predict worse DFS (P = .172, HR = 1.276) or shorter OS (P = .433, HR = 1.183). CONCLUSION: A kinase-interacting protein 1 may serve as a potential biomarker for deteriorative tumor features and poor prognosis in gastric cancer patients.

Somatostatin Octapeptide Inhibits Cell Invasion and Metastasis in Hepatocellular Carcinoma Through PEBP1.

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) is a major threat to human health. The condition carries a high risk of death; 45% of new cases occur in China. Surgical resection is the first choice for treatment of HCC, but 30.9% of patients experience recurrence within 6 months after the operation. To improve patient survival, we must determine how to reduce the probability of recurrence and metastasis and elucidate the underlying mechanism of disease. We therefore studied the effect of somatostatin octapeptide (octreotide) on the invasion and metastasis of HCC. METHODS: The migration and invasion cytological tests were used to detect the effect of octreotide on liver cancer cells (SK-Hep-1 and HepG2). PEBP1 RNAi was used to knockdown expression. Invasion and metastasis were measured with transwell migration and wound-healing assays. Western blotting was used to detect changes in levels of PEBP1 and invasion pathway proteins after octreotide treatment. The effect of octreotide was studied in vivo by establishing a pulmonary metastasis model using SK-Hep-1 cells in nude mice. In-vivo bioluminescence imaging and hematoxylin and eosin staining of lung tissue were used to verify the results. RESULTS: Increasing concentrations of octreotide were progressively more effective in halting the invasion and metastasis of liver cancer cells. Octreotide may upregulate PEBP1, TIMP-2, and E-cadherin while downregulating MMP-2 and Twist to inhibit cell invasion and metastasis. And downregulation of PEBP1 would also change the expression of MMP-2, TIMP-2 and Twist. The in-vivo experiments showed no cancer cell metastasis in 4 of the 6 mice in the octreotide-treatment group, while all of the mice in the control group displayed pulmonary metastasis of human HCC cells. And the survival period of the mice in the octreotide-treatment group was significantly prolonged. CONCLUSIONS: Octreotide may weaken invasion and metastasis through the upregulation of PEBP1. Octreotide may reduce the risk of recurrence and metastasis after surgery for liver cancer.

PLGA-nanoparticle mediated delivery of anti-OX40 monoclonal antibody enhances anti-tumor cytotoxic T cell responses.

OX40 (CD134) is a tumor necrosis factor (TNF) receptor expressed mainly on activated T cells and transmits a potent costimulatory signal once engaged. Agonistic anti-OX40 monoclonal antibody (mAb) enhances tumor immune response leading to therapeutic effects in mouse tumor models. However, when tested in phase I clinical trials it did not show objective clinical activity in cancer patients. In this study, we examined the feasibility of nanoparticle (NP)-mediated delivery of anti-OX40 mAb to efficiently induce cytotoxic T lymphocyte (CTL) responses. The biodegradable poly(DL-lactide-co-glycolide) nanoparticle (PLGA-NP) carrying anti-OX40 mAb, anti-OX40-PLGA-NP, was prepared by double emulsion method and showed an average diameter of 86 nm with a loading efficiency of 25%. We found that anti-OX40-PLGA-NP induced CTL proliferation and tumor antigen-specific cytotoxicity as well as cytokine production more strongly than free anti-OX40 mAb. These results suggest that PLGA-based nanoparticle formulation may provide efficient delivery system of anti-OX40 mAb for cancer immunotherapy.

Decreased expression of liver-type fatty acid-binding protein is associated with poor prognosis in hepatocellular carcinoma.

BACKGROUND/AIMS: The purpose of this study was to assess liver-type fatty acid-binding protein (L-FABP) expression and its association with clinicopathological features in hepatocellular carcinoma (HCC). METHODOLOGY: L-FABP mRNA expression in 57 samples of HCC and corresponding adjacent liver tissue and 8 normal liver tissue samples were examined by real-time reverse transcriptase (RT)­PCR analyses. Tissue microarray technique and immunohistochemistry (IHC) were used to detect the expression of L-FABP in 163 HCCs. The association between L-FABP expression and the clinicopathological factors and prognosis was analyzed. RESULTS: The average expression of L-FABP mRNA was 0.233 in the HCC tissues, 1.407 in the peri-carcinoma tissues, and 1.0 in the normal liver tissues. IHC analysis showed that there were 47% (76/163) HCCs exhibited weak or even no immunoreactivity of L-FABP. The L-FABP expression in HCC showed significant associations with preoperative levels of AFP (p=0.039), tumor size (p=0.026), histological grade (p=0.000), differential degree (p=0.000), vascular invasion (p=0.016), capsular invasion (p=0.029) and recurrence (p=0.004). Patients with L-FABP high-expression showed better prognosis than patients with L-FABP low-expression (p=0.008). CONCLUSIONS: L-FABP was downregulated in HCC and could be served as a promising prognostic marker for HCC patients.

Predictive indicators of immune therapy efficacy in hepatocellular carcinoma based on neutrophil-to-lymphocyte ratio.

Hepatocellular carcinoma (HCC) exhibits high incidence and mortality rates in China. Most cases are often diagnosed at late stages and require multi-strategy therapies. In recent years, immune checkpoint inhibitors (ICIs), particularly programmed cell death protein 1 (PD-1) antibodies, have demonstrated effectiveness in comprehensive HCC treatment. However, the efficacy and prognosis vary greatly among patients. Screening suitable patients and predicting outcomes are crucial for improving the efficacy of ICIs. Although PD-L1 expression levels in tumor cells have been used as predictors of PD-1/PD-L1 antibody therapy, they may not consistently correlate with clinical response in some studies; thus, exploring new biomarkers is necessary. The neutrophil-to-lymphocyte ratio (NLR) emerged as a new predictor of ICI immunotherapy efficacy, and its application in HCC is worth exploring. This study utilizes the Cancer Genome Atlas Liver Hepatocellular Carcinoma Collection (TCGA-LIHC) project in the Genomic Data Commons (GDC) database for methylation and transcriptome data analysis. The correlation between NLR and ICI immunotherapy efficacy for HCC was evaluated, identifying differentially expressed genes. Analysis revealed 74 up-regulated and 445 down-regulated genes in the high-NLR group compared to the low-NLR group. NLR-related differential methylation analysis identified 68 hypermethylated and 65 hypomethylated probes in the NLR high group. Furthermore, a machine learning model using 27 intersecting genes predicted PD-1 antibody therapy efficacy, achieving an AUC value of 0.813. In summary, we established a predictive model for HCC immunotherapy based on 27 genes related to differential expressions and NLR-associated methylation, showing significant potential for clinical research potential in this field.

Combination of microparticles vaccine with MSI-1436 exerts a strong immune response for hepatocellular carcinoma.

Although tumor cell-derived microparticles (MPs) vaccines have reportedly induced antitumor immune reactions for various cancers, the mechanism by which MPs derived from Hepa1-6 cells are taken up by dendritic cells (DCs) and provide the MPs antigens message to CD8+ T cells to exert their anti-hepatocellular carcinoma (HCC) effects remain unclear. Furthermore, the role of MPs in combination with the small-molecule drug MSI-1436, an inhibitor of protein tyrosine phosphatase 1B (PTP1B), in HCC has not yet been reported. In this study, protein mass spectrometry combined with cytology revealed that MPs are mainly taken up by DCs via the clathrin-mediated endocytosis and phagocytosis pathway and localized mainly in lysosomes. High concentration of tumor necrosis factor-α and interferon-γ was detected in CD8+ T cells stimulated with MPs-loaded DCs. Moreover, MPs combined with MSI-1436 further suppressed the proliferation of HCC cells in C57BL/6 tumor-bearing mice, which was closely correlated with CD4+/CD8+ T cells counts in peripheral blood, spleen, and the tumor microenvironment. Mechanistically, the combination of MPs and MSI-1436 exerts a more powerful anti-HCC effect, which may be related to the further inhibition of the expression of PTP1B. Overall, MPs combined with MSI-1436 exerted stronger antitumor effects than MPs or MSI-1436 alone. Therefore, the combination of MPs and MSI-1436 may be a promising means of treating HCC.

BCL2A1 neoepitope-elicited cytotoxic T lymphocytes are a promising individualized immunotherapy of pancreatic cancer.

Conventional treatments have shown a limited efficacy for pancreatic cancer, and immunotherapy is an emerging option for treatment of this highly fatal malignancy. Neoantigen is critical to improving the efficacy of tumor-specific immunotherapy. The cancer and peripheral blood specimens from an HLA-A0201-positive pancreatic cancer patient were subjected to next-generation sequencing, and bioinformatics analyses were performed to screen high-affinity and highly stable neoepitopes. The activation of cytotoxic T lymphocytes (CTLs) by dendritic cells (DCs) loaded with mutBCL2A111-20 neoepitope targeting a BCL2A1 mutant epitope was investigated, and the cytotoxicity of mutBCL2A111-20 neoepitope-specific CTLs to pancreatic cancer cells was evaluated. The mutBCL2A111-20 neoepitope was found to present a high immunogenicity and induce CTLs activation and proliferation, and these CTLs were cytotoxic to mutBCL2A111-20 neoepitope-loaded T2 cells and pancreatic cancer PANC-1-Neo and A2-BxPC-3-Neo cells that overexpressed mutBCL2A111-20 neoepitopes, appearing to be a targeting neoepitope specificity. In addition, high BCL2A1 expression correlated with a low 5-yr progression-free interval among pancreatic cancer patients. Our findings provide experimental supports to individualized T cell therapy targeting mutBCL2A111-20 neoepitopes, and provide an option of immunotherapy for pancreatic cancer.

Targeting Nuclear Receptor Coactivator SRC-1 Prevents Colorectal Cancer Immune Escape by Reducing Transcription and Protein Stability of PD-L1.

Programmed death-ligand 1 (PD-L1) is overexpressed in multiple cancers and critical for their immune escape. It has previously shown that the nuclear coactivator SRC-1 promoted colorectal cancer (CRC) progression by enhancing CRC cell viability, yet its role in CRC immune escape is unclear. Here, we demonstrate that SRC-1 is positively correlated with PD-L1 in human CRC specimens. SRC-1 deficiency significantly inhibits PD-L1 expression in CRC cells and retards murine CRC growth in subcutaneous grafts by enhancing CRC immune escape via increasing tumor infiltration of CD8+ T cells. Genetic ablation of SRC-1 in mice also decreases PD-L1 expression in AOM/DSS-induced murine CRC. These results suggest that tumor-derived SRC-1 promotes CRC immune escape by enhancing PD-L1 expression. Mechanistically, SRC-1 activated JAK-STAT signaling by inhibiting SOCS1 expression and coactivated STAT3 and IRF1 to enhance PD-L1 transcription as well as stabilized PD-L1 protein by inhibiting proteasome-dependent degradation mediated by speckle type POZ protein (SPOP). Pharmacological inhibition of SRC-1 improved the antitumor effect of PD-L1 antibody in both subcutaneous graft and AOM/DSS-induced murine CRC models. Taken together, these findings highlight a crucial role of SRC-1 in regulating PD-L1 expression and targeting SRC-1 in combination with PD-L1 antibody immunotherapy may be an attractive strategy for CRC treatment.

Characterization of the Prognosis and Tumor Microenvironment of Cellular Senescence-related Genes through scRNA-Seq and Bulk RNA-Seq Analysis in GC.

BACKGROUND: Cellular senescence (CS) is thought to be the primary cause of cancer development and progression. This study aimed to investigate the prognostic role and molecular subtypes of CS-associated genes in gastric cancer (GC). METHODS: The CellAge database was utilized to acquire CS-related genes. Expression data and clinical information of GC patients were obtained from The Cancer Genome Atlas (TCGA) database. Patients were then grouped into distinct subtypes using the "ConsesusClusterPlus" R package based on CS-related genes. An in-depth analysis was conducted to assess the gene expression, molecular function, prognosis, gene mutation, immune infiltration, and drug resistance of each subtype. In addition, a CS-associated risk model was developed based on Cox regression analysis. The nomogram, constructed on the basis of the risk score and clinical factors, was formulated to improve the clinical application of GC patients. Finally, several candidate drugs were screened based on the Cancer Therapeutics Response Portal (CTRP) and PRISM Repurposing dataset. RESULTS: According to the cluster result, patients were categorized into two molecular subtypes (C1 and C2). The two subtypes revealed distinct expression levels, overall survival (OS) and clinical presentations, mutation profiles, tumor microenvironment (TME), and drug resistance. A risk model was developed by selecting eight genes from the differential expression genes (DEGs) between two molecular subtypes. Patients with GC were categorized into two risk groups, with the high-risk group exhibiting a poor prognosis, a higher TME level, and increased expression of immune checkpoints. Function enrichment results suggested that genes were enriched in DNA repaired pathway in the low-risk group. Moreover, the Tumor Immune Dysfunction and Exclusion (TIDE) analysis indicated that immunotherapy is likely to be more beneficial for patients in the low-risk group. Drug analysis results revealed that several drugs, including ML210, ML162, dasatinib, idronoxil, and temsirolimus, may contribute to the treatment of GC patients in the high-risk group. Moreover, the risk model genes presented a distinct expression in single-cell levels in the GSE150290 dataset. CONCLUSION: The two molecular subtypes, with their own individual OS rate, expression patterns, and immune infiltration, lay the foundation for further exploration into the GC molecular mechanism. The eight gene signatures could effectively predict the GC prognosis and can serve as reliable markers for GC patients.

KRAS mutation and NF-κB activation indicates tolerance of chemotherapy and poor prognosis in colorectal cancer.

BACKGROUND: Evidence shows a strong relationship between KRAS mutations and the NF-κB signaling pathway. In colorectal cancer, however, the study of this subject has been very limited and results are inconsistent. AIMS: To examine the relationship between KRAS mutations and NF-κB activation and their effect on chemotherapy response and survival of colorectal cancer patients. MATERIALS AND METHODS: NF-κB activation was analyzed by immunohistochemistry in 167 primary colorectal cancer specimens in which the KRAS mutation status was confirmed. Clinical and pathologic data were extracted from the medical records and reviewed. RESULTS: Of 167 tumors screened, 63 (37.7 %) had NF-κB activation, 59 (35.3 %) had KRAS mutations, and 30 (18.0 %) had both NF-κB activation and KRAS mutations. The frequency of NF-κB activation in tumors with KRAS mutations was significantly higher than in tumors with wild type KRAS; 50.8 versus 30.6 %, P = 0.012. Patients with both KRAS mutations and NF-κB activation had a lower objective response to first-line chemotherapy than patients with other tumors, 23.8 versus 49.4 % (P = 0.035). Compared to patients with both KRAS mutations and NF-κB activation, overall survival of patients in other groups was significantly higher; median overall survival was 28.4 months (95 % CI 21.0-35.8) versus 46.3 months (95 % CI 39.4-53.2), hazard ratio 0.259 (95 % CI 0.125-0.538), P = 0.005. CONCLUSIONS: NF-κB activation was associated with KRAS mutation, and both KRAS mutation and NF-κB activation were indicative of high tolerance of chemotherapy and poor prognosis for colorectal cancer patients. Tumors with KRAS mutations and NF-κB activation may be a unique subtype of colorectal cancer.

Interleukin-15 and chemokine ligand 19 enhance cytotoxic effects of chimeric antigen receptor T cells using zebrafish xenograft model of gastric cancer.

Chimeric antigen receptor (CAR) T cells have been proven effective for the treatment of B-cell-mediated malignancies. Currently, the development of efficient tools that supply CAR T cells for the treatment of other malignancies would have great impact. In this study, interleukin (IL)-15 and C-C motif chemokine ligand 19 (CCL19) were introduced into natural killer group 2D (NKG2D)-based CARs to generate 15×19 CAR T cells, which remarkably increased T-cell expansion and promoted the production of central memory T (Tcm) cells. 15×19 CAR T cells showed greater cytotoxicity to gastric cell lines than conventional CAR T cells and produced higher levels of IL-15 and CCL-19, which resulted in increased responder T cell chemotaxis and reduced expression of T cell exhaustion markers. A live zebrafish model was used for single-cell visualization of local cytotoxicity and metastatic cancers. Administration of 15×19 CAR T cells resulted in significant shrinking of gastric cancer xenograft tumors and expansion of 15×19 CAR T cells in zebrafish models. Taken together, these findings demonstrate that 15×19 CAR T cells are highly efficient in killing gastric cancer cells, are effective to avoid off-target effects, and migrate to local and metastatic sites for long-term surveillance of cancers.

Inhibitor of DNA binding 2 knockdown inhibits the growth and liver metastasis of colorectal cancer.

BACKGROUND: Liver metastasis of colorectal cancer (CRC) remains high mortality and the mechanism is still unknown. Here we investigated the effects of inhibitor of DNA binding 2 (Id2) on growth and liver metastasis of CRC. METHODS: qPCR and western blotting were used to demonstrate mRNA and protein expressions in Id2-knockdown HCT116 cells. Cell growth was observed by cell proliferation assay, colony formation assay and flow cytometry. Cell migration and invasion were observed with wound healing assay and transwell migration and invasion assay. The effects of Id2 knockdown on tumor growth and liver metastasis in vivo were evaluated respectively with subcutaneous tumor model and colorectal liver metastasis model by injecting HCT116 cells into the mesentery triangle of cecum in mice. RESULTS: Id2 overexpression was found in CRC cell lines. Id2 knockdown resulted in a reduction in the proliferation, colony formation, migration and invasion of HCT116 cells. The suppression of cell proliferation was accompanied by the cell cycle arrest in the G0/G1 phase with down-regulation of Cyclin D1, Cyclin E, p-Cdk2/3, Cdk6, p-p27 and up-regulation of p21 and p27. Id2 knockdown reversed epithelial-mesenchymal transition (EMT) through increasing E-Cadherin and inhibiting N-Cadherin, Vimentin, ß-catenin, Snail and Slug. Id2 was also found to inhibit CRC metastasis via MMP2, MMP9 and TIMP-1. Furthermore, Id2 knockdown suppressed CRC liver metastasis in vivo. CONCLUSION: Id2 promotes CRC growth through activation of the PI3K/AKT signaling pathway, and triggers EMT to enhance CRC migration and invasion.