Microenvironment-induced CREPT expression by cancer-derived small extracellular vesicles primes field cancerization.

Rationale: Cancer local recurrence increases the mortality of patients, and might be caused by field cancerization, a pre-malignant alteration of normal epithelial cells. It has been suggested that cancer-derived small extracellular vesicles (CDEs) may contribute to field cancerization, but the underlying mechanisms remain poorly understood. In this study, we aim to identify the key regulatory factors within recipient cells under the instigation of CDEs. Methods: In vitro experiments were performed to demonstrate that CDEs promote the expression of CREPT in normal epithelial cells. TMT-based quantitative mass spectrometry was employed to investigate the proteomic differences between normal cells and tumor cells. Loss-of-function approaches by CRISPR-Cas9 system were used to assess the role of CREPT in CDEs-induced field cancerization. RNA-seq was performed to explore the genes regulated by CREPT during field cancerization. Results: CDEs promote field cancerization by inducing the expression of CREPT in non-malignant epithelial cells through activating the ERK signaling pathway. Intriguingly, CDEs failed to induce field cancerization when CREPT was deleted, highlighting the importance of CREPT. Transcriptomic analyses revealed that CDEs elicited inflammatory responses, primarily through activation of the TNF signaling pathway. CREPT, in turn, regulates the transduction of downstream signals of TNF by modulating the expression of TNFR2 and PI3K, thereby promoting inflammation-to-cancer transition. Conclusion: CREPT not only serves as a biomarker for field cancerization, but also emerges as a target for preventing the cancer local recurrence.

Comprehensive Multiomics Analyses Establish the Optimal Prognostic Model for Resectable Gastric Cancer : Prognosis Prediction for Resectable GC.

BACKGROUND: Prognostic models based on multiomics data may provide better predictive capability than those established at the single-omics level. Here we aimed to establish a prognostic model for resectable gastric cancer (GC) with multiomics information involving mutational, copy number, transcriptional, methylation, and clinicopathological alterations. PATIENTS AND METHODS: The mutational, copy number, transcriptional, methylation data of 268, 265, 226, and 252 patients with stages I-III GC were downloaded from the TCGA database, respectively. Alterations from all omics were characterized, and prognostic models were established at the individual omics level and optimized at the multiomics level. All models were validated with a cohort of 99 patients with stages I-III GC. RESULTS: TTN, TP53, and MUC16 were among the genes with the highest mutational frequency, while UBR5, ZFHX4, PREX2, and ARID1A exhibited the most prominent copy number variations (CNVs). Upregulated COL10A1, CST1, and HOXC10 and downregulated GAST represented the biggest transcriptional alterations. Aberrant methylation of some well-known genes was revealed, including CLDN18, NDRG4, and SDC2. Many alterations were found to predict the patient prognosis by univariate analysis, while four mutant genes, two CNVs, five transcriptionally altered genes, and seven aberrantly methylated genes were identified as independent risk factors in multivariate analysis. Prognostic models at the single-omics level were established with these alterations, and optimized combination of selected alterations with clinicopathological factors was used to establish a final multiomics model. All single-omics models and the final multiomics model were validated by an independent cohort. The optimal area under the curve (AUC) was 0.73, 0.71, 0.71, and 0.85 for mutational, CNV, transcriptional, and methylation models, respectively. The final multiomics model significantly increased the AUC to 0.92 (P < 0.05). CONCLUSIONS: Multiomics model exhibited significantly better capability in predicting the prognosis of resectable GC than single-omics models.

Evaluation of the advantages of robotic versus laparoscopic surgery in elderly patients with colorectal cancer.

BACKGROUND: The incidence of colorectal cancer increases with aging. Curative-intent surgery based on a minimally invasive concept is expected to bring survival benefits to elderly patients (aged over 80 years) with colorectal cancer who are frequently with fragile health status and advanced tumors. The study explored survival outcomes in this patient population who received robotic or laparoscopic surgery and aimed to identify an optimal surgical option for those patients. METHODS: We retrieved the clinical materials and follow-up data on elderly patients with colorectal carcinoma who received robotic or laparoscopic surgery in our institution. The pathological and surgical outcomes were compared to examine the efficacy and safety of the two approaches. The DFS (disease-free survival) and OS (overall survival) results at 3 years after surgery were assessed to explore the survival benefits. RESULTS: A total of 111 patients were screened for the study, including 55 in the robotic group and 56 in the laparoscopic group. The demographic details were generally similar between the two groups. No statistically significant difference in the number of removed lymph nodes was observed between the two approaches, with a median of 15 versus 14 (P = 0.053). The intraoperative blood loss was significantly reduced by robotic technique when compared to the laparoscopic approach, with a mean of 76.9 ml versus 161.6 ml (P = 0.025). There were no significant differences in operation time, conversion, postoperative complications and recovery, and long-term outcomes between the two groups. CONCLUSION: Robotic surgery was prized for elderly patients with colorectal cancer who developed anemia and/or hematological conditions.

Immunodeficiencies Push Readmissions in Malignant Tumor Patients: A Retrospective Cohort Study Based on the Nationwide Readmission Database.

BACKGROUND: Immunodeficiency diseases (IDDs) are associated with an increased proportion of cancer-related morbidity. However, the relationship between IDDs and malignancy readmissions has not been well described. Understanding this relationship could help us to develop a more reasonable discharge plan in the special tumor population. METHODS: Using the Nationwide Readmissions Database, we established a retrospective cohort study that included patients with the 16 most common malignancies, and we defined two groups: non-immunodeficiency diseases (NOIDDs) and IDDs. RESULTS: To identify whether the presence or absence of IDDs was associated with readmission, we identified 603,831 patients with malignancies at their time of readmission in which 0.8% had IDDs and in which readmission occurred in 47.3%. Compared with NOIDDs, patients with IDDs had a higher risk of 30-day (hazard ratio (HR) of 1.32; 95% CI of 1.25-1.40), 90-day (HR of 1.27; 95% CI of 1.21-1.34) and 180-day readmission (HR of 1.28; 95% CI of 1.22-1.35). More than one third (37.9%) of patients with IDDs had readmissions that occurred within 30 days and most (82.4%) of them were UPRs. An IDD was an independent risk factor for readmission in patients with colorectal cancer (HR of 1.32; 95% CI of 1.01-1.72), lung cancer (HR of 1.23; 95% CI of 1.02-1.48), non-Hodgkin's lymphoma (NHL) (HR of 1.16; 95% CI of 1.04-1.28), prostate cancer (HR of 1.45; 95% CI of 1.07-1.96) or stomach cancer (HR of 2.34; 95% CI of 1.33-4.14). Anemia (44.2%), bacterial infections (28.6%) and pneumonia (13.9%) were the 30-day UPR causes in these populations. (4) Conclusions: IDDs were independently associated with higher readmission risks for some malignant tumors. Strategies should be considered to prevent the causes of readmission as a post discharge plan.

Association of CSMD1 with Tumor Mutation Burden and Other Clinical Outcomes in Gastric Cancer.

BACKGROUND: Immunotherapy is considered as a powerful and promising clinical approach for the treatment of gastric cancer (GC). However, it is still challenging to precisely screen patients who potentially benefit from immune checkpoint therapy (ICT). Identification of potential biomarkers for selecting patients sensitive to immunotherapy was urgently needed. METHODS: Public sequence data and corresponding clinical data were used to explore the potential biomarkers for immunotherapy. RESULTS: We found that CSMD1 is the most frequently mutated gene and its mutation is highly correlated with prognosis in gastric cancer patients. Interestingly, patients with mutated CSMD1 exhibit a high mutation burden and upregulated PDL1 expression. The ratio of microsatellite instability (MSI) in the CSMD1 mutation cohort was higher than that in the cohort without CSMD1 mutation. Furthermore, patients with CSMD1 mutation have been found to possess a higher number of activated CD4+ T cells and neoantigens. CONCLUSION: CSMD1 mutation may act as a novel biomarker for assessing the survival and immune therapy response in patients with gastric cancer.

CREPT/RPRD1B promotes tumorigenesis through STAT3-driven gene transcription in a p300-dependent manner.

BACKGROUND: Signal transducer and activator of transcription 3 (STAT3) has been shown to upregulate gene transcription during tumorigenesis. However, how STAT3 initiates transcription remains to be exploited. This study is to reveal the role of CREPT (cell cycle-related and elevated-expression protein in tumours, or RPRD1B) in promoting STAT3 transcriptional activity. METHODS: BALB/c nude mice, CREPT overexpression or deletion cells were employed for the assay of tumour formation, chromatin immunoprecipitation, assay for transposase-accessible chromatin using sequencing. RESULTS: We demonstrate that CREPT, a recently identified oncoprotein, enhances STAT3 transcriptional activity to promote tumorigenesis. CREPT expression is positively correlated with activation of STAT3 signalling in tumours. Deletion of CREPT led to a decrease, but overexpression of CREPT resulted in an increase, in STAT3-initiated tumour cell proliferation, colony formation and tumour growth. Mechanistically, CREPT interacts with phosphorylated STAT3 (p-STAT3) and facilitates p-STAT3 to recruit p300 to occupy at the promoters of STAT3-targeted genes. Therefore, CREPT and STAT3 coordinately facilitate p300-mediated acetylation of histone 3 (H3K18ac and H3K27ac), further augmenting RNA polymerase II recruitment. Accordingly, depletion of p300 abolished CREPT-enhanced STAT3 transcriptional activity. CONCLUSIONS: We propose that CREPT is a co-activator of STAT3 for recruiting p300. Our study provides an alternative strategy for the therapy of cancers related to STAT3.

CREPT is required for murine stem cell maintenance during intestinal regeneration.

Intestinal stem cells (ISCs) residing in the crypts are critical for the continual self-renewal and rapid recovery of the intestinal epithelium. The regulatory mechanism of ISCs is not fully understood. Here we report that CREPT, a recently identified tumor-promoting protein, is required for the maintenance of murine ISCs. CREPT is preferably expressed in the crypts but not in the villi. Deletion of CREPT in the intestinal epithelium of mice (Vil-CREPTKO) results in lower body weight and slow migration of epithelial cells in the intestine. Vil-CREPTKO intestine fails to regenerate after X-ray irradiation and dextran sulfate sodium (DSS) treatment. Accordingly, the deletion of CREPT decreases the expression of genes related to the proliferation and differentiation of ISCs and reduces Lgr5+ cell numbers at homeostasis. We identify that CREPT deficiency downregulates Wnt signaling by impairing ß-catenin accumulation in the nucleus of the crypt cells during regeneration. Our study provides a previously undefined regulator of ISCs.

Genome-Wide Analysis of Methylation-Driven Genes and Identification of an Eight-Gene Panel for Prognosis Prediction in Breast Cancer.

BACKGROUND: Aberrant DNA methylation is a crucial epigenetic regulator that is closely related to the occurrence and development of various cancers, including breast cancer (BC). The present study aimed to identify a novel methylation-based prognosis biomarker panel by integrally analyzing gene expression and methylation patterns in BC patients. METHODS: DNA methylation and gene expression data of breast cancer (BRCA) were downloaded from The Cancer Genome Atlas (TCGA). R packages, including ChAMP, SVA, and MethylMix, were applied to identify the unique methylation-driven genes. Subsequently, these genes were subjected to Metascape for GO analysis. Univariant Cox regression was used to identify survival-related genes among the methylation-driven genes. Robust likelihood-based survival modeling was applied to define the prognosis markers. An independent data set (GSE72308) was used for further validation of our risk score system. RESULTS: A total of 879 DNA methylation-driven genes were identified from 765 BC patients. In the discovery cohort, we identified 50 survival-related methylation-driven genes. Finally, we built an eight-methylation-driven gene panel that serves as prognostic predictors. CONCLUSIONS: Our analysis of transcriptome and methylome variations associated with the survival status of BC patients provides a further understanding of basic biological processes and a basis for the genetic etiology in BC.

Identification of Eight Small Nucleolar RNAs as Survival Biomarkers and Their Clinical Significance in Gastric Cancer.

Gastric cancer is one of most common cancers worldwide. Studies have shown that small nucleolar RNAs (snoRNAs) play important roles in several cancers. In this study, we analyzed the snoRNAs that were differentially expressed between gastric tumors and normal tissues, identified survival-associated snoRNAs, and developed an eight-snoRNA signature to predict overall survival of patients with gastric cancer. Furthermore, we explored the clinical significance of the eight signature snoRNAs. The risk biomarker established by the eight snoRNA signature was an independent prognostic factor (hazard ratio = 3.43, 95% confidence interval: 1.93-6.09, P = 2.72e-05). Furthermore, we validated the expression pattern of those snoRNAs in different gastric cancer cell lines and 5 paired normal and tumor tissues by using real time quantification PCR. Knocking down U66, one of the eight snoRNAs, inhibited the cell proliferation. In conclusion, we identified an eight-snoRNA risk signature to predict overall survival of gastric cancer patients. Seven of these snoRNAs were associated with clinical features of the disease. Knocking down U66 inhibited cell proliferation. These findings provide new clues with prognostic and therapeutic implications in gastric cancer.

CREPT/RPRD1B associates with Aurora B to regulate Cyclin B1 expression for accelerating the G2/M transition in gastric cancer.

Gastric cancer, like most of other cancers, has an uncontrolled cell cycle regulated by cyclins and cyclin-dependent kinases (CDKs). In this study, we reported that gastric cancer cells showed an accelerated G2/M transition promoted by CREPT/RPRD1B and Aurora kinase B (Aurora B). We found that CREPT/RPRD1B and Aurora B were coordinately expressed during the cell cycle in gastric cancer cells. Deletion of CREPT/RPRD1B disturbed the cell progression and extended the length of cell cycle, leading to a significant accumulation of mitotic cells. Mechanistically, we revealed that CREPT/RPRD1B interacted with Aurora B to regulate the expression of Cyclin B1 in gastric cancer cells. Interestingly, Aurora B phosphorylates S145 in a well-conserved motif of CREPT/RPRD1B. We proposed that phosphorylation of CREPT/RPRD1B by Aurora B is required for promoting the transcription of Cyclin B1, which is critical for the regulation of gastric tumorigenesis. Our study provides a mechanism by which gastric tumor cells maintain their high proliferation rate via coordination of Aurora B and CREPT/RPRD1B on the expression of Cyclin B1. Targeting the interaction of Aurora B and CREPT/RPRD1B might be a strategy for anti-gastric cancer therapy in the future.

A 15-lncRNA signature predicts survival and functions as a ceRNA in patients with colorectal cancer.

PURPOSE: Colorectal cancer (CRC) is one of the most common malignant tumors worldwide. This study aimed to explore the prognostic value of lncRNAs in CRC. MATERIAL AND METHODS: We performed gene expression profiling to identify differentially expressed lncRNAs between 51 normal and 646 tumor tissues from The Cancer Genome Atlas database. Cox regression and robust likelihood-based survival models were used to find prognosis-related lncRNAs. A lncRNA signature was developed to predict the overall survival of patients with CRC. In addition, a receiver operating characteristic curve analysis was performed to identify the optimal cutoff with the best Youden index to divide patients into different groups based on risk level. RESULTS: Eighty survival-related lncRNAs were identified and a 15-lncRNA signature was developed on the basis of a risk score to comprehensively predict the overall survival of patients with CRC. The prognostic value of the 15-lncRNA risk score was validated using the internal testing set and total set. The risk indicator was shown to be an independent prognostic factor (hazard ratio =2.92; 95% CI: 1.73-4.94; P<0.001). Notably, all 15 lncRNAs (AC024581.1, FOXD3-AS1, AC012531.1, AC003101.2, LINC01219, AC083967.1, AL590483.1, AC105118.1, AC010789.1, AC067930.5, AC105219.2, LINC01354, LINC02474, LINC02257, and AC079612.1) were newly found to correlate with the prognosis of patients with CRC. Furthermore, the function of 15 lncRNAs was explored through the ceRNA network. These lncRNAs regulated coding genes that were involved in many key cancer pathways. CONCLUSION: A 15-lncRNA expression signature was discovered as a prognostic indicator for patients with CRC, which may act as competing endogenous RNA (ceRNAs) to play a crucial role in the modulation of cancer-related pathways. These findings may allow a better understanding of the prognostic value of lncRNAs.

Overexpression of CREPT confers colorectal cancer sensitivity to fluorouracil.

AIM: To investigate expression of cell cycle-related and expression-elevated protein in tumor (CREPT) in colorectal cancer (CRC) and determine its prognostic value in response to 5-fluorouracil (5-FU). METHODS: The relative expression of CREPT in CRC tumor samples was determined using immunohistochemistry. The protein content in cell lines was analyzed by immunoblotting. Cell viability was measured with the CCK-8 assay. Cell cycle and apoptosis analyses were performed with flow cytometry. RESULTS: CREPT was overexpressed in CRC tissues and correlated with histological grade. Clinicopathological analysis indicated that CREPT was positively related to tumor progression. Exogenous expression of CREPT stimulated cell proliferation and accelerated the cell cycle. More importantly, high expression of CREPT sensitized CRC cells to 5-FU treatment. Furthermore, we demonstrated that 5-FU elicited significant apoptosis in CREPT-positive cells. CONCLUSION: Aberrant overexpression of CREPT contributes to tumorigenesis of CRC by promoting cell proliferation and accelerating the cell cycle, and confers sensitivity to 5-FU. CREPT is a potential prognostic biomarker for 5-FU in CRC.