Tumor immunotherapy resistance: Revealing the mechanism of PD-1 / PD-L1-mediated tumor immune escape.

Tumor immunotherapy, an innovative anti-cancer therapy, has showcased encouraging outcomes across diverse tumor types. Among these, the PD-1/PD-L1 signaling pathway is a well-known immunological checkpoint, which is significant in the regulation of immune evasion by tumors. Nevertheless, a considerable number of patients develop resistance to anti-PD-1/PD-L1 immunotherapy, rendering it ineffective in the long run. This research focuses on exploring the factors of PD-1/PD-L1-mediated resistance in tumor immunotherapy. Initially, the PD-1/PD-L1 pathway is characterized by its role in facilitating tumor immune evasion, emphasizing its role in autoimmune homeostasis. Next, the primary mechanisms of resistance to PD-1/PD-L1-based immunotherapy are analyzed, including tumor antigen deletion, T cell dysfunction, increased immunosuppressive cells, and alterations in the expression of PD-L1 within tumor cells. The possible ramifications of altered metabolism, microbiota, and DNA methylation on resistance is also described. Finally, possible resolution strategies for dealing with anti-PD-1/PD-L1 immunotherapy resistance are discussed, placing particular emphasis on personalized therapeutic approaches and the exploration of more potent immunotherapy regimens.

Exploring the pharmacological mechanism of Wuzhuyu decoction on hepatocellular carcinoma using network pharmacology.

BACKGROUND: Wuzhuyu decoction, a traditional Chinese medicinal formula, is effective in treating hepatocellular carcinoma (HCC). AIM: To explore the potential mechanism of action of Wuzhuyu decoction against HCC. METHODS: The active components of each Chinese herbal medicinal ingredient in Wuzhuyu decoction and their targets were obtained from the Traditional Chinese Medicine Database and Analysis Platform. HCC was used as a search query in GeneCards, Online Mendelian Inheritance in Man, Malacards, DisGeNET, Therapeutic Target Database, and Comparative Toxicogenomics Database. The overlapping targets of the Wuzhuyu decoction and HCC were defined, and then protein-protein interaction, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed. CytoHubba was used to select hub genes, and their binding activities and key active components were verified using molecular docking. RESULTS: A total of 764 compounds, 77 active compounds, and 204 potential target genes were identified in Wuzhuyu decoction. For HCC, 9468 potential therapeutic target genes were identified by combining the results from the six databases and removing duplicates. A total of 179 overlapping targets of Wuzhuyu decoction and HCC were defined, including 10 hub genes (tumor necrosis factor, interleukin-6, AKT1, TP53, caspase-3, mitogen-activated protein kinase 1, epidermal growth factor receptor, MYC, mitogen-activated protein kinase 8, and JUN). There were six main active components (quercetin, kaempferol, ginsenoside Rh2, rutaecarpine, ß-carotene, and ß-sitosterol) that may act on hub genes to treat HCC in Wuzhuyu decoction. Kyoto Encyclopedia of Genes and Genomes enrichment analysis mainly involved the mitogen-activated protein kinase, p53, phosphatidylinositol-4,5-bisphosphate 3-kinase-Akt, Janus kinase-signal transducer of activators of transcription, and Hippo signaling pathways. Further verification based on molecular docking results showed that the small molecule compounds (quercetin, kaempferol, ginsenoside Rh2, rutaecarpine, ß-carotene, and ß-sitosterol) contained in Wuzhuyu decoction generally have excellent binding affinity to the macromolecular target proteins encoded by the top 10 genes. CONCLUSION: This study revealed that Wuzhuyu decoction may be a latent multicomponent, multitarget, and multipathway treatment for HCC. It provided novel insights for verifying the mechanism of Wuzhuyu decoction in the treatment of HCC.

Recent advances in optical aptasensors for biomarkers in early diagnosis and prognosis monitoring of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) accounts for approximately 90% of all primary liver cancers and is one of the main malignant tumor types globally. It is essential to develop rapid, ultrasensitive, and accurate strategies for the diagnosis and surveillance of HCC. In recent years, aptasensors have attracted particular attention owing to their high sensitivity, excellent selectivity, and low production costs. Optical analysis, as a potential analytical tool, offers the advantages of a wide range of targets, rapid response, and simple instrumentation. In this review, recent progress in several types of optical aptasensors for biomarkers in early diagnosis and prognosis monitoring of HCC is summarized. Furthermore, we evaluate the strengths and limitations of these sensors and discuss the challenges and future perspectives for their use in HCC diagnosis and surveillance.

Single-Cell RNA Sequencing Analysis of the Heterogeneity in Gene Regulatory Networks in Colorectal Cancer.

Colorectal cancer (CRC) manifests as gastrointestinal tumors with high intratumoral heterogeneity. Recent studies have demonstrated that CRC may consist of tumor cells with different consensus molecular subtypes (CMS). The advancements in single-cell RNA sequencing have facilitated the development of gene regulatory networks to decode key regulators for specific cell types. Herein, we comprehensively analyzed the CMS of CRC patients by using single-cell RNA-sequencing data. CMS for all malignant cells were assigned using CMScaller. Gene set variation analysis showed pathway activity differences consistent with those reported in previous studies. Cell-cell communication analysis confirmed that CMS1 was more closely related to immune cells, and that monocytes and macrophages play dominant roles in the CRC tumor microenvironment. On the basis of the constructed gene regulation networks (GRNs) for each subtype, we identified that the critical transcription factor ERG is universally activated and upregulated in all CMS in comparison with normal cells, and that it performed diverse roles by regulating the expression of different downstream genes. In summary, molecular subtyping of single-cell RNA-sequencing data for colorectal cancer could elucidate the heterogeneity in gene regulatory networks and identify critical regulators of CRC.

Tribbles pseudokinase 3 (TRIB3) contributes to the progression of hepatocellular carcinoma by activating the mitogen-activated protein kinase pathway.

BACKGROUND: Tribble pseudokinase 3 (TRIB3) plays a key role in regulating the malignancy of many tumors. This study examined its function in cancer cells and explored the potential mechanisms of action. METHODS: The expression of TRIB3 was examined in hepatocellular carcinomas (HCCs) using The Cancer Genome Atlas (TCGA) database. A TRIB3 lentivirus with a flag label was constructed and transfected into Huh7 and Hep3B human hepatoma cell lines to generate cells that stably overexpress TRIB3. A small interfering RNA (siRNA) was designed to knockdown TRIB3 mRNA in HepG2 and Huh7. Cell viability and cell colony formation assays were conducted. Flow cytometry was performed to assess the cell cycle in cells overexpressing TRIB3. Western blotting were performed to examine the expression of (Mitogen-activated protein kinase, MAPKK) (MEK), phosphorylated-MEK (p-MEK), extracellular signal-regulated kinase (ERK), and p-MEK in cells with TRIB3 knockdown. The correlation between TRIB3 and SMARCD3 was assessed using co-immunoprecipitation assays and immunofluorescence. RESULTS: TRIB3 was significantly overexpressed in advanced grade HCC tissues and was closely correlated with poor prognosis. TRIB3 overexpression promoted the cell growth and cell cycle but had little effect on migration capabilities in Huh7 and Hep3B cells. Conversely, knockdown of TRIB3 had slow down the cell growth in Huh7 and HepG2 cells detected by CCK8 and colony formation assay. The expression of MEK and ERK at both the protein and mRNA levels were downregulated when TRIB3 was knocked down. The protein expression of p-ERK and p-MEK were also downregulated upon TRIB3 silencing. SMARCD3 is a transcript factor that is belongs to the SWI/SNF complex and has been shown to regulate many genes. Indeed, co-immunoprecipitation assays demonstrated that TRIB3 interacts with SMARCD3 in the nucleus, suggesting that it may regulate TRIB3 in HCCs. CONCLUSIONS: This study demonstrated that TRIB3 promotes the malignancy of HCC cells and its expression may be a potential diagnostic biomarker for HCC progression.

[Identification of a novel PHOX2A gene mutation in a Chinese family with congenital fibrosis of extraocular muscles type 2].

OBJECTIVE: To investigate potential mutation of PHOX2A (or ARIX) gene in a Chinese family affected with congenital fibrosis of extraocular muscles tyep 2 (CFEOM2). METHODS: Genomic DNA was obtained from affected and unaffected members of the family. With an ABI PRSIM Linkage Mapping Set-MD10 kit, selected markers flanking the PHOX2A locus were used for linkage analysis. Exons of PHOX2 gene were amplified and sequenced. A total of 100 normal subjects were recruited as controls. RESULTS: Genetic linkage was found at 11q13 between D11S4151 and D11S1320 and the PHOX2A gene. DNA sequencing has identified a heterozygous mutation in the exon 2 of the gene (227T to G, N76K). The same mutation was not found in the unaffected and 100 normal controls. CONCLUSION: A mutation of the PHOX2A gene 227T to G is responsible for the onset of congenital fibrosis of extraocular muscles type 2 in this Chinese family.

Structural changes in exon 11 of MEF2A are not related to sporadic coronary artery disease in Han Chinese population.

BACKGROUND: A mutation in MEF2A (myocyte enhancer factor-2A) had been reported to be the first gene linked directly to coronary artery disease (CAD). However, an opposing opinion was proposed recently that MEF2A mutations are not a common cause of sporadic CAD. In this study, we screened exon 11 of the MEF2A gene in people of the Han nationality in China and finished some functional analysis of found variations. MATERIALS AND METHODS: A gene structural investigation of MEF2A in 257 CAD patients and 154 control individuals were developed in this study. Subsequently, typical MEF2A variations were cloned and expressed in HeLa or 293T cell line to illustrate whether found structure changes could influence the main biological functions of these proteins. At last, another set of gene structural screen was initialized to get more reliable conclusions. RESULTS: Totally 16 different variations were detected in exon 11 of this gene in the first set of gene structural screen. By cloning and expressing typical MEF2A proteins in cultured cells, all the acquired MEF2A variations had transcriptional activation capabilities and subcellular localization patterns similar to those of the wild-type protein. Further larger scale genetic screening also revealed that the reported genetic variations of MEF2A did not differ significantly between CAD patients and healthy controls. CONCLUSIONS: Our results reveal that structural changes of exon 11 in MEF2A are not involved in sporadic CAD in the Han population of China.

[Linkage analysis of a Chinese family with autosomal dominant congenital retinaochoroidal coloboma].

OBJECTIVE: To map the candidate gene by linkage analysis in a Chinese family with autosomal dominant congenital retinaochoroidal coloboma. METHODS: A detailed clinical examination was performed for all patients in the family. The genomic DNA of all family members was extracted from peripheral blood leukocytes. Linkage analysis and genome-wide linkage screening was conducted using fluorescent detection of 398 microsatellite markers representing all autosomes at an average resolution of approximately 10 cM. Polymerase chain reaction was carried out to amplify all 398 microsatellite markers. The allele sizes were determined on ABI 3130-Avant genetic analyzer according to an internal size standard, and the results were analyzed using Genescan 3.1 and Genotyper 2.0 software. RESULTS: Linkage analysis showed the markers D2S2382-D2S301-D2S2244-D2S163 co-segregated with the disease locus in all affected members. The maximum Lod score was 3.01(D2S2382). CONCLUSION: The candidate region of the disease gene in the family was located in 2q34-2q35.

Identification of a genetic locus for autosomal dominant infantile cataract on chromosome 20p12.1-p11.23 in a Chinese family.

PURPOSE: To map a gene responsible for infantile cataract in a large four-generation, non-consanguineous Chinese family. METHODS: Twenty-two family members including 17 cataract patients in the Chinese family were analyzed clinically. All family members were genotyped with 382 microsatellite markers that provide genome-wide coverage every 10 cM. Linkage analysis was performed to identify the chromosomal location of the infantile cataract gene in the family. Candidate genes were studied by direct DNA sequence analysis. RESULTS: Genome-wide linkage analysis provided evidence for a genetic locus for infantile cataract on chromosome 20p12.2-20p11.23. The maximum LOD score was 5.15 for marker D20S471 at a recombination fraction of 0. Fine mapping defined the cataract gene within a 7.4 Mb interval between markers D20S915 and D20S912. No mutation was detected in potential candidate genes, BFSP1 and CHMP4B. CONCLUSIONS: Our results suggest that there is a new gene for infantile cataract on chromosome 20p12.2-p11.23. Our results suggest that new genes for infantile cataract could be found through further study of candidate genes at the 20q locus, which may provide insights into the pathogenic mechanisms of cataracts.