Oncogenic role of karyopherin α2 (KPNA2) in human tumors: A pan-cancer analysis

Spatial Proteomic Profiling of Colorectal Cancer Revealed Its Tumor Microenvironment Heterogeneity

Colorectal cancer is a predominant malignancy with a second mortality worldwide. Despite its prevalence, therapeutic options remain constrained and surgical operation is still the most useful therapy. In this regard, a comprehensive spatially resolved quantitative proteome atlas was constructed to explore the functional proteomic landscape of colorectal cancer. This strategy integrates histopathological analysis, laser capture microdissection, and proteomics. Spatial proteome profiling of 200 tissue section samples facilitated by the fully integrated sample preparation technology SISPROT enabled the identification of more than 4000 proteins on the Orbitrap Exploris 240 from 2 mm2 × 10 μm tissue sections. Compared with normal adjacent tissues, we identified a spectrum of cancer-associated proteins and dysregulated pathways across various regions of colorectal cancer including ascending colon, transverse colon, descending colon, sigmoid colon, and rectum. Additionally, we conducted proteomic analysis on tumoral epithelial cells and paracancerous epithelium from early to advanced stages in hallmark rectum cancer and sigmoid colon cancer. Bioinformatics analysis revealed functional proteins and cell-type signatures associated with different regions of colorectal tumors, suggesting potential clinical implications. Overall, this study provides a comprehensive spatially resolved functional proteome landscape of colorectal cancer, serving as a valuable resource for exploring potential biomarkers and therapeutic targets.

Hsa_circRNA_007630 knockdown delays colon cancer progression by modulation of ferroptosis via miR-506-3p/AURKA axis

Colon cancer contributes to high mortality rates internationally that has seriously endangered human health. Aurora kinase A (AURKA) served as a key molecule in colon cancer. However, its role of AURKA on regulating ferroptosis in colon cancer and their possible interactions with miRNAs and circRNAs remain still elusive. Comprehensive bioinformatics analysis after RNA-sequencing was conducted to determine the differentially expressed genes (DEGs), ferroptosis-related DEGs and hub genes. The direct relationship between miR-506-3p and hsa_circRNA_007630 or AURKA was predicted, then verified by dual luciferase reporter and quantitative real-time polymerase chain reaction. The rescue experiments were conducted by cotransfection with si-hsa_circRNA_007630, miR-506-3p inhibitor or pcDNA-AURKA in HT29 cells. Erastin was used to induce ferroptosis in HT29 cells and validated by detecting levels of intracellular Fe2+, lipid reactive oxygen species, glutathione, malondialdehyde and ferroptosis markers expression. We screened a total of 331 DEGs, 26 ferroptosis-related genes, among which 3 hub genes were identified through PPI network analysis. Therein, AURKA expression was elevated in colon cancer cells. Moreover, AURKA was targeted by miR-506-3p, and hsa_circRNA_007630 operated as miR-506-3p sponge. The effect of hsa_circRNA_007630 depletion on the inhibiting malignant phenotypes of HT29 cells was rescued by inhibition of miR-506-3p or AURKA overexpression. Additionally, AURKA reduced erastin-induced ferroptosis in HT29 cells. Depletion of circRNA_007630 exerts as a suppressive role in colon cancer through a novel miR-506-3p/AURKA pathway related to ferroptosis, and might become a novel marker for colon cancer.

Oxidative stress mediates nucleocytoplasmic shuttling of KPNA2 via AKT1-CDK1 axis-regulated S62 phosphorylation

Karyopherin α 2 (KPNA2, importin α1), a transport factor shuttling between the nuclear and cytoplasmic compartments, is involved in the nuclear import of proteins and participates in cellular processes such as cell cycle regulation, apoptosis, and transcriptional regulation. However, it is still unclear which signaling regulates the nucleocytoplasmic distribution of KPNA2 in response to cellular stress. In this study, we report that oxidative stress increases nuclear retention of KPNA2 through alpha serine/threonine-protein kinase (AKT1)-mediated reduction of serine 62 (S62) phosphorylation. We first found that AKT1 activation was required for H2O2-induced nuclear accumulation of KPNA2. Immunoprecipitation and quantitative proteomic analysis revealed that the phosphorylation of KPNA2 at S62 was decreased under H2O2-induced oxidative stress. We showed that cyclin-dependent kinase 1 (CDK1), a kinase responsible for KPNA2 S62 phosphorylation, contributes to the localization of KPNA2 in the cytoplasm. AKT1 knockdown increased KPNA2 S62 phosphorylation and inhibited CDK1 activation. Furthermore, H2O2-induced AKT1 activation promoted nuclear KPNA2 interaction with nucleophosmin 1 (NPM1), resulting in attenuation of NPM1-mediated cyclin D1 gene transcription. Thus, we infer that the AKT1-CDK1 axis regulates the nucleocytoplasmic shuttling and function of KPNA2 through spatiotemporal regulation of KPNA2 S62 phosphorylation under oxidative stress conditions.

KPNA2 promotes the progression of gastric cancer by regulating the alternative splicing of related genes

RNA-binding proteins (RBPs) play critical roles in genome regulation. In this study, we explored the latent function of KPNA2, which is an essential member of the RBP family, in the regulation of alternative splicing (AS) in gastric cancer (GC). We analyzed the role of KPNA2 in regulating differential expression and AS via RNA sequencing (RNA-seq) and improved RNA immunoprecipitation sequencing (iRIP-seq). Clinical specimens were used to analyze the associations between KPNA2 expression and clinicopathological characteristics. CCK8 assays, transwell assays and wound healing assays were performed to explore the effect of KPNA2/WDR62 on GC cell progression. KPNA2 was shown to be highly expressed in GC cells and tissues and associated with lymph node metastases. KPNA2 promoted the proliferation, migration and invasion of GC cells and primarily regulated exon skipping, alternative 3's splice sites (A3SSs), alternative 5' splice sites (A5SSs), and cassette exons. We further revealed that KPNA2 participated in biological processes related to cell proliferation, and the immune response in GC via the regulation of transcription. In addition, KPNA2 preferentially bound to intron regions. Notably, KPNA2 regulated the A3SS AS mode of WDR62, and upregulation of WDR62 reversed the KPNA2 downregulation-induced inhibition of GC cell proliferation, migration and invasion. Finally, we discovered that the AS of immune-related molecules could be regulated by KPNA2. Overall, our results demonstrated for the first time that KPNA2 functions as an oncogenic splicing factor in GC that regulated the AS and differential expression of GC-related genes, and KPNA2 may be a potential target for GC treatment.

Proteomic profiling improves prognostic risk stratification of the Sarculator nomogram in soft tissue sarcomas of the extremities and trunk wall

BACKGROUND

High-risk soft tissue sarcomas of the extremities and trunk wall (eSTS), as defined by the Sarculator nomogram, are more likely to benefit from (neo)adjuvant anthracycline-based therapy compared to low/intermediate-risk patients. The biology underpinning these differential treatment outcomes remain unknown.

METHODS

We analysed proteomic profiles and clinical outcomes of 123 eSTS patients. A Cox model for overall survival including the Sarculator was fitted to individual data to define four risk groups. A DNA replication protein signature-Sarcoma Proteomic Module 6 (SPM6) was evaluated for association with clinicopathological factors and risk groups. SPM6 was added as a covariate together with Sarculator in a multivariable Cox model to assess improvement in prognostic risk stratification.

RESULTS

DNA replication and cell cycle proteins were upregulated in high-risk versus very low-risk patients. Evaluation of the functional effects of CRISPR-Cas9 gene knockdown of proteins enriched in high-risk patients using the cancer cell line encyclopaedia database identified candidate drug targets. SPM6 was significantly associated with tumour malignancy grade (p = 1.6e-06), histology (p = 1.4e-05) and risk groups (p = 2.6e-06). Cox model analysis showed that SPM6 substantially contributed to a better calibration of the Sarculator nomogram (Index of Prediction Accuracy = 0.109 for Sarculator alone versus 0.165 for Sarculator + SPM6).

CONCLUSIONS

Risk stratification of patient with STS is defined by distinct biological pathways across a range of cancer hallmarks. Incorporation of SPM6 protein signature improves prognostic risk stratification of the Sarculator nomogram. This study highlights the utility of integrating protein signatures for the development of next-generation nomograms.

MiRNA and Potential Prognostic Value in Non-Smoking Females with Lung Adenocarcinoma by High-Throughput Sequencing

Background

Non-smoking females with lung adenocarcinoma (LUAD) account for a unique disease entity and miRNA play critical roles in cancer development and progression. The purpose of this study is to explore prognosis-related differentially expressed miRNA (DEmiRNA) and establish a prognostic model for non-smoking females with LUAD.

Methods

Eight specimens were collected from thoracic surgery of non-smoking females with LUAD and implemented the miRNA sequencing. The intersection of our miRNA sequencing data and TCGA database were identified as common DEmiRNA. Then, we predicted the target genes of the common DEmiRNAs (DETGs) and explored the functional enrichment and prognosis of DETGs. A risk model by overall survival (OS)-related DEmiRNA was constructed based on multivariate Cox regression analyses.

Results

A total of 34 overlapping DEmiRNA were obtained. The DETGs were enriched in pathways including "Cell cycle" and "miRNAs in cancer". The DETGs (KPNA2, CEP55, TRIP13, MYBL2) were risk factors, significantly related to OS, progression-free survival (PFS), and were also hub genes. ScRNA-seq data also validated the expression of the four DETGs. Hsa-mir-200a, hsa-mir-21, and hsa-mir-584 were significantly associated with OS. The prognostic prediction model constructed by the 3 DEmiRNA could effectively predict OS and can be used as an independent prognostic factor of non-smoking females with LUAD.

Conclusion

Hsa-mir-200a, hsa-mir-21, and hsa-mir-584 can serve as potential prognostic predictors in non-smoking females with LUAD. A novel prognostic model based on the three DEmiRNAs was also constructed to predict the survival of non-smoking females with LUAD and showed good performance. The result of our paper can be helpful for treatment and prognosis prediction for non-smoking females with LUAD.

A sensitive double antibodies sandwich ELISA for the diagnosis and therapeutic evaluation of cervical cancer

BACKGROUND

Vascular endothelial growth factor (VEGF) is a highly specific factor for tumors growth. However, the study on the mechanism of VEGF in cervical cancer, and the correlation between the expression level of VEGF and the therapeutic evaluation, prognosis of cervical cancer is not clear till now.

METHODS

In this study, RT-qPCR and IHC were used to evaluate the abnormal expression of VEGF in cervical cancer. The survival plots of the VEGF expression related to OS were observed by using the KM plotter. The mAbs against VEGF were screened and identified by ELISA addicted test, indirect ELISA, Western-blot, and dot-ELISA. We designed and prepared the overlapping truncations (V1, V2, V3) of VEGF to identify the B cell epitopes. Then, the epitopes recognized by anti-VEGF mAbs were mapped and displayed on a 3D structure of VEGF by using the PyMOL software. The highly specific and sensitive sandwich ELISA was established to detect the total VEGF quantification in 206 clinical sera samples, thus to evaluate the changes of VEGF before and after chemoradiotherapy in cervical cancer patients.

RESULTS

The VEGF was high expressed in cervical cancer tissues and cells, resulting a poor prognosis of cervical cancer. The mAbs 2E5 and 6D9 were selected with the titer of 1:256000 and 1:128000 respectively. The mAbs both had strong ability to combine with VEGF protein within 15 min and were identified as subclass IgG1 with κ-type light chains. 2E5 bound to V1 and V2, recognizing the N-terminal (1-121 aa) of VEGF, however 6D9 bound to V3, recognizing the C-terminal (116-174 aa) of VEGF. The 206 clinical samples were tested with the established VEGF-DAS-ELISA and calculated according to the equation (y = 0.0042088× + 0.105109, R² = 0.998). The results indicated that the expression levels of VEGF in cervical cancer samples were positively higher than those in normal samples. Importantly, we found the expression level of sera VEGF in cervical cancer patients decreased significantly after chemoradiotherapy. Therefore, the variable of VEGF levels in cervical cancer patients before and after treatment can be used as a new indicator of efficacy evaluation to guide the clinical treatment of cervical cancer.

CONCLUSION

A sensitive DAS-ELISA was established successfully, using which we can track the VEGF to evaluate the efficacy and estimate prognosis of cervical cancer. It is helpful for the diagnosis, therapeutic evaluation and prognosis of cervical cancer.

Exploration of an Prognostic Signature Related to Endoplasmic Reticulum Stress in Colorectal Adenocarcinoma and Their Response Targeting Immunotherapy

Background: Endoplasmic reticulum (ER) stress plays a pro-apoptotic role in colorectal adenocarcinoma (COAD). This study aimed to develop a novel ER-stress-related prognostic risk model for COAD and provide support for COAD cohorts with different risk score responses to immune checkpoint inhibitor therapies. Methods: TCGA-COAD and GSE39582 were included in this prospective study. Univariate and multivariate Cox analyses were performed to identify prognostic ER stress-related genes (ERSGs). Accordingly, the immune infiltration landscape and immunotherapy response in different risk groups were assessed. Finally, the expression of prognostic genes in 10 normal and 10 COAD tissue samples was verified using reverse transcription-quantitative polymerase chain reaction. Results: Eight prognostic genes were selected to establish an ERSG-based signature in the training set of the TCGA-COAD cohort. The accuracy of this was confirmed using a testing set of TCGA-COAD and GSE39582 cohorts. Gene set variation analysis indicated that differential functionality in high-low-risk groups was related to immune-related pathways. Corresponding to this, CD36, TIMP1, and PTGIS were significantly associated with 19 immune cells with distinct proportions between the different risk groups, such as central memory CD4T cells and central memory CD8T cells. Moreover, the risk score was considered effective for predicting the clinical response to immunotherapy, and the immunotherapy response was significantly and negatively correlated with the risk score of individuals with COAD. Furthermore, the immune checkpoint inhibitor treatment was less effective in the high-risk group, where the expression levels of PD-L1 and tumor immune dysfunction and exclusion scores in the high-risk group were significantly increased. Finally, the experimental results demonstrated that the expression trends of prognostic genes in clinical samples were consistent with the results from public databases. Conclusion: Our study established a novel risk signature to predict the COAD prognosis of patients and provide theoretical support for the clinical treatment of COAD.

Oncogenic KPNA2 Serves as a Biomarker and Immune Infiltration in Patients With HPV Positive Tongue Squamous Cell Carcinoma

Human tongue squamous cell carcinoma (TSCC), the most prevalent type of oral cancer, is associated with human papillomavirus (HPV) infection. Our previous work showed Karyopherin α2 (KPNA2), as an oncogene of TSCC, by relegating the p53/autophagy signaling pathway. Nevertheless, the significance of KPNA2 in TSCC pathogenesis has not been established. KPNA2 levels were evaluated via the TCGA database, and its effects on survival outcomes were assessed by LASSO, Kaplan‐Meier, and COX regression analyses. CIBERSORT and ESTIMATE investigated the relationships between KPNA2 and immune infiltration. At the same time, KPNA2 and HPV infection was analyzed by immunohistochemistry. In addition, the association between downstream molecular regulation pathways and KPNA2 levels was determined by GO, GSEA, and WGCNA. In TSCC, KPNA2 levels were associated with clinical prognosis and tumor grade. Moreover, KPNA2 may be involved in cancer cell differentiation and facilitates tumor-related genes and signaling pathways, such as Cell Cycle, Mitotic G1 phase, G1/S transition, DNA Repair, and Transcriptional Regulation TP53 signaling pathways. Nevertheless, regulatory B cells, follicular helper B cells, and immune and stromal scores between low- and high-KPNA2 expression groups were insignificant. These results imply that KPNA2 is highly involved in tumor grade and prognosis of TSCC. KPNA2 levels correct with HPV 16 markedly regulated cell differentiation, several oncogenes, and cancer‐related pathways.

Mechanisms of Cell Cycle Arrest and Apoptosis in Glioblastoma

Cells of glioblastoma, the most frequent primary malignant brain tumor, are characterized by their rapid growth and infiltration of adjacent healthy brain parenchyma, which reflects their aggressive biological behavior. In order to maintain their excessive proliferation and invasion, glioblastomas exploit the innate biological capacities of the patients suffering from this tumor. The pathways involved in cell cycle regulation and apoptosis are the mechanisms most commonly affected. The following work reviews the regulatory pathways of cell growth in general as well as the dysregulated cell cycle and apoptosis relevant mechanisms observed in glioblastomas. We then describe the molecular targeting of the current established adjuvant therapy and present ongoing trials or completed studies on specific promising therapeutic agents that induce cell cycle arrest and apoptosis of glioblastoma cells.

Identification and verification of YBX3 and its regulatory gene HEIH as an oncogenic system: A multidimensional analysis in colon cancer

The novel gene YBX3 is important for regulating translation and RNA catabolism and encodes a protein with a highly conserved cold-shock domain. However, its pathogenic roles across cancers (e.g., colon cancer) and its regulation remain unclear. We identified the pathogenic roles of YBX3 and its regulatory lncRNA HEIH in various cancers and investigated their effects on tumor progression in colon cancer. Methods including RNA pull-down, MS, and TMA of 93 patients, qPCR of 12 patients with diverse clinicopathologic stages, and western blotting were performed. The pancancer analysis showed that YBX3 expression varies significantly among not only cancer types but also molecular and immune subtypes of the same cancer. Furthermore, its expression in colon cancer is clinically significant, and there is an obvious negative regulatory association between HEIH and YBX3. Among various cancers, especially colon cancer, YBX3 is more related than HEIH expression to the clinical features and prognosis of subgroups. The receiver operating characteristic analysis showed that HEIH and YBX3 have similar predictive capacity in various cancers. The analysis of differentially expressed genes in colon cancer revealed that they have similar hub gene networks, indicating an oncogenic system with a strong overlap. The results also suggest that YBX3 is associated with tumor immune evasion via different mechanisms involving T-cell exclusion in different cancer types and by the tumor infiltration of immune cells. Interestingly, scRNA-seq revealed that HEIH inhibits this phenomenon. Our results also suggest that YBX3 expression is associated with immune or chemotherapeutic outcomes in various cancers, and YBX3 exhibited a higher predictive power than two of seven standardized biomarkers for response outcomes and overall survival of immune checkpoint blockade subcohorts. In colon cancer cell lines, lncRNA-HEIH and YBX3 associate. MS confirmed that YBX3 was pulled down with HEIH, and western blot showed that HEIH knockdown disinhibited YBX3. This study strongly suggests that lncRNA-HEIH/YBX3 is a pancancer immune-oncogenic system and could serve as a biomarker for diagnosis and prognosis and as a therapeutic target, especially in colon cancer.