Micro-power negative pressure wound technique reduces risk of incision infection following loop ileostomy closure.

BACKGROUND: Prophylactic loop ileostomy is an effective way to reduce the clinical severity of anastomotic leakage following radical resection of rectal cancer. Incisional surgical site infection (SSI) is a common complication after ileostomy closure. AIM: To evaluate the efficacy and safety of the micro-power negative pressure wound technique (MPNPWT) in preventing incisional SSI. METHODS: This was a prospective, randomized controlled clinical trial conducted at a single center. A total of 101 consecutive patients who underwent ileostomy closure after rectal cancer surgery with a prophylactic ileostomy were enrolled from January 2019 to December 2021. Patients were randomly allocated into an MPNPWT group and a control group. The MPNPWT group underwent intermittent suturing of the surgical incision with 2-0 Prolene and was covered with a micro-power negative pressure dressing. The surgical outcomes were compared between the MPNPWT (n = 50) and control (n = 51) groups. Risk factors for incisional SSI were identified using logistic regression. RESULTS: There were no differences in baseline characteristics between the MPNPWT (n = 50) and control groups (n = 51). The incisional SSI rate was significantly higher in the control group than in the MPNPWT group (15.7% vs 2.0%, P = 0.031). However, MPNPWT did not affect other surgical outcomes, including intra-abdominal complications, operative time, and blood loss. Postoperative hospital stay length and hospitalization costs did not differ significantly between the two groups (P = 0.069 and 0.843, respectively). None of the patients experienced adverse effects of MPNPWT, including skin allergy, dermatitis, and pain. MPNPWT also helped heal the infected incision. Our study indicated that MPNPWT was an independent protective factor [odds ratio (OR) = 0.005, P = 0.025)] and diabetes was a risk factor (OR = 26.575, P= 0.029) for incisional SSI. CONCLUSION: MPNPWT is an effective and safe way to prevent incisional SSI after loop ileostomy closure.

Pyroptosis in cancer treatment and prevention: the role of natural products and their bioactive compounds.

Targeting programmed cell death (PCD) has been emerging as a promising therapeutic strategy in cancer. Pyroptosis, as a type of PCDs, leads to the cleavage of the gasdermin family and the secretion of pro-inflammatory factors. Gasdermin D (GSDMD) and gasdermin E (GSDME) are the two main executors of pyroptosis. Pyroptosis in tumor and immune cells is essential for tumor progression. Natural products, especially Chinese medicinal herb and their bioactive compounds have recently been regarded as anti-tumor agents that regulate cell pyroptosis under different circumstances. Here, we review the underlying mechanisms of natural products that activate pyroptosis in tumor cells and inhibit pyroptosis in immune cells. Pyroptosis activation in tumor cells leads to tumor cell death, yet pyroptosis inhibition in immune cells may prevent tumor occurrence. Elucidation of the signaling pathways involved in pyroptosis contributes to the understanding of the anti-tumor role of natural products and their potential clinical applications. Therefore, we outline a promising strategy for cancer therapy and prevention using natural products via modulation of pyroptosis.

Genetic effect of metformin use on risk of cancers: evidence from Mendelian randomization analysis.

BACKGROUND: Increasing number of studies reported the positive effect of metformin on the prevention and treatment of cancers. However, the genetic causal effect of metformin utilization on the risk of common cancers was not completely demonstrated. METHODS: Two-sample Mendelian Randomization (two-sample MR) analysis was conducted to uncover the genetically predicted causal association between metformin use and 26 kinds of cancers. Besides, two-step Mendelian Randomization (two-step MR) assessment was applied to clarify the mediators which mediated the causal effect of metformin on certain cancer. We utilized five robust analytical methods, in which the inverse variance weighting (IVW) method served as the major one. Sensitivity, pleiotropy, and heterogeneity were assessed. The genetic statistics of exposure, outcomes, and mediators were downloaded from publicly available datasets, including the Open Genome-Wide Association Study (GWAS), FinnGen consortium (FinnGen), and UK Biobank (UKB). RESULTS: Among 26 kinds of common cancers, HER-positive breast cancer was presented with a significant causal relationship with metformin use [Beta: - 4.0982; OR: 0.0166 (95% CI: 0.0008, 0.3376); P value: 0.0077], which indicated metformin could prevent people from HER-positive breast cancer. Other cancers only showed modest associations with metformin use. Potential mediators were included in two-step MR, among which total testosterone levels (mediating effect: 24.52%) displayed significant mediating roles. Leave-one-out, MR-Egger, and MR-PRESSO analyses produced consistent outcomes. CONCLUSION: Metformin use exhibited a genetically protective effect on HER-positive breast cancer, which was partially mediated by total testosterone levels.

A WGCNA-based cancer-associated fibroblast risk signature in colorectal cancer for prognosis and immunotherapy response.

Background: Cancer-associated fibroblasts (CAFs) are notably involved in colorectal cancer (CRC) tumorigenesis, progression, and treatment failure. In this article, we report the in silico development of a CAF-related prognostic signature for CRC. Methods: We separately downloaded CRC transcription data from The Cancer Genome Atlas and the Gene Expression Omnibus database. Deconvolution algorithms, including Estimating the Proportions of Immune and Cancer Cells and the Microenvironment Cell Population-counter, were used to calculate CAF abundance, while the Estimation of Stromal and Immune cells in Malignant Tumor tissues using Expression algorithm was used to calculate the stromal score. Weighted gene co-expression network analysis (WGCNA) and the least absolute shrinkage and selection operator algorithm were used to identify CAF-related genes and prognostic signatures. Results: We identified a three-gene, prognostic, CAF-related signature and defined risk groups based on the Riskscores. Multidimensional validations were applied to evaluate the robustness of the signature and its correlation with clinical parameters. We utilized Tumor Immune Dysfunction and Exclusion (TIDE) and oncoPredict algorithms to predict therapy responses and found that patients in low-risk groups are more sensitive to immunotherapy and chemotherapy drugs such as 5-fluorouracil and oxaliplatin. Finally, we used the Cancer Cell Line Encyclopedia and Human Protein Atlas databases to evaluate the mRNA and protein levels encoded by the signature genes. Conclusions: This novel CAF-related three-gene signature is expected to become a potential prognostic biomarker in CRC and predict chemotherapy and immunotherapy responses. It may be of considerable value for studying the tumor microenvironment in CRC.

BMAL1 promotes colorectal cancer cell migration and invasion through ERK- and JNK-dependent c-Myc expression.

BACKGROUND: Cancer metastasis is still a life threat to patients with colorectal cancer (CRC). Brain and muscle ARNT-like protein 1 (BMAL1) is an important biological proteins that can regulate the behavior of cancer cells and their response to chemotherapy. However, the role of BMAL1 in the tumorigenic phenotype of CRC remains unclear. Here, we aim to investigate the functional role and mechanisms of BMAL1 in CRC. METHODS: The mRNA expression of BMAL1 was studied using the Cancer Genome Atlas (TCGA) databases. The protein level in clinical tissues was confirmed by immunohistochemistry (IHC). The effects of BMAL1 on the epithelial-to-mesenchymal transition (EMT) and proliferation of CRC cell lines (including BMAL1 overexpressed or silencing cells) were studied by Transwell, wound healing, CCK-8 and colony formation experiments. A series of experiments were conducted to demonstrate the mechanisms of BMAL1 regulating EMT and cancer proliferation in vitro and in vivo. RESULTS: We found that BMAL1 expression was closely related to the poor prognosis of CRC. BMAL1 overexpression promoted cell proliferation and migration. Mechanistically, we found that BMAL1 may activate the epithelial-to-mesenchymal transition (EMT) pathway and induce the ß-catenin release further promotes the expression of oncogene c-Myc and the migration of colorectal cells by activating MAPK pathway. However, BMAL1 silencing achieved the opposite effect. In addition, blocking MAPK-signaling pathway with specific inhibitors of ERK1/2 and JNK can also downregulate the expressions of c-Myc in vitro. Taken together, these results suggested that the BMAL1/ c-Myc-signaling pathway may regulate the metastasis of CRC through the JNK/ERK1/2 MAPK-dependent pathway. CONCLUSIONS: Our study showed that BMAL1 promotes CRC metastasis through MAPK-c-Myc pathway. These results deepen our understanding of the relationship between BMAL1 and tumorigenic phenotypes, which may become a promising therapeutic target for BMAL1 overexpressing CRC.

Anti-PD-1 combined with targeted therapy: Theory and practice in gastric and colorectal cancer.

Gastric cancer (GC) and colorectal cancer (CRC) are frequent and aggressive malignancies worldwide. Despite the emergence of various therapeutic regimens, the prognosis of gastric and colorectal cancer is relatively poor. Immunotherapy targeting PD-1 is one of the most prevalent approaches, but it has a low response rate in most patients, particularly those with microsatellite stability (MSS). Recently, some targeted drugs have been found to remarkably enhance the anti-tumor immunity of cancer models, mainly through increasing the level of CD8+ T cells, M1-type macrophages, expression of PD-L1, and decreasing the level of regulatory T cells and M2 macrophages. The above finding implies that the combination of anti-PD-1 and targeted therapies may be a potential treatment for gastric and colorectal cancer patients. Although many encouraging preclinical results have been shown, the clinical outcomes were not approving enough. To further enhance the therapeutic efficacy and improve the prognosis in GC and CRC patients, deeper and larger-scale studies should be done to determine the complicated interactions between the two therapies and the concrete use of combination regimens.

Orally Administrable Therapeutic Nanoparticles for the Treatment of Colorectal Cancer.

Colorectal cancer (CRC) is one of the most common and lethal human malignancies worldwide; however, the therapeutic outcomes in the clinic still are unsatisfactory due to the lack of effective and safe therapeutic regimens. Orally administrable and CRC-targetable drug delivery is an attractive approach for CRC therapy as it improves the efficacy by local drug delivery and reduces systemic toxicity. Currently, chemotherapy remains the mainstay modality for CRC therapy; however, most of chemo drugs have low water solubility and are unstable in the gastrointestinal tract (GIT), poor intestinal permeability, and are susceptible to P-glycoprotein (P-gp) efflux, resulting in limited therapeutic outcomes. Orally administrable nanoformulations hold the great potential for improving the bioavailability of poorly permeable and poorly soluble therapeutics, but there are still limitations associated with these regimes. This review focuses on the barriers for oral drug delivery and various oral therapeutic nanoparticles for the management of CRC.

Therapeutic effects of dihydroartemisinin in multiple stages of colitis-associated colorectal cancer.

Colitis-associated colorectal cancer (CAC) develops from chronic intestinal inflammation. Dihydroartemisinin (DHA) is an antimalarial drug exhibiting anti-inflammatory and anti-tumor effects. Nonetheless, the therapeutic effects of DHA on CAC remain unestablished. Methods: Mice were challenged with azoxymethane (AOM) and dextran sulfate sodium (DSS) to establish CAC models. DHA was administered via oral gavage in different stages of CAC models. Colon and tumor tissues were obtained from the AOM/DSS models to investigate inflammatory responses and tumor development. Inflammatory cytokines in the murine models were detected through qRT-PCR and ELISA. Toll-like receptor 4 (TLR4) signaling-related proteins were detected by western blot. Macrophage infiltration was measured using immunostaining analysis, and apoptosis in the colon cancer cells was detected by flow cytometry and western blot. Results: DHA inhibited inflammatory responses in the early stage of the AOM/DSS model and subsequent tumor formation. In the early stage, DHA reversed macrophage infiltration in colon mucosa and decreased the expression of pro-inflammatory cytokines. DHA inhibited the activation of macrophage by suppressing the TLR4 signal pathway. In the late stage of CAC, DHA inhibited tumor growth by enhancing cell cycle arrest and apoptosis in tumor cells. Administration of DHA during the whole period of the AOM/DSS model generated an addictive effect based on the inhibition of inflammation and tumor growth, thereby improving the therapeutic effect of DHA on CAC. Conclusion: Our study indicated that DHA could be a potent agent in managing the initiation and development of CAC without obvious side effects, warranting further clinical translation of DHA for CAC treatment.

Comparative genomic signatures in young and old Chinese patients with colorectal cancer.

BACKGROUND: Occurrence at a young age is known to be associated with unique clinical features in colorectal cancer (CRC). However, the genomic differences between young and old patients with CRC are not well elucidated and, to the best of our knowledge, have never been investigated in a Chinese population. METHODS: Tumor tissue samples from 29 young (age ≤50 years) and 46 old (age >50 years) patients with CRC were collected. Targeted sequencing of 808 cancer-related genes was conducted to characterize the genomic landscape for Chinese CRC. RESULTS: Overall, mutational profiles exhibited notable differences between the two groups. In particular, APC and PIK3CA mutations were more frequently observed in old patients (p = 0.009 and p = 0.012, respectively), while SMAD4 mutations tended to occur in young patients (p = 0.054). Mutation loci distributions of KRAS in the young cohort differed from those in the old cohort, and a higher frequency of KRAS codon 12 mutations was potentially associated with a young age (p = 0.076). The frequencies of clinically actionable alterations were analyzed by defined age categories, which unveiled a distinctive targeted genomic profile in the young group. Furthermore, among patients with mismatch repair-proficient (pMMR) CRC, tumor mutation burden (TMB) was positively correlated with age (Pearson's r = 0.306, p = 0.011), and genomic alterations associated with high TMB in young patients differentiated from those in old patients. CONCLUSIONS: These findings revealed different molecular characterization between young and old Chinese patients with CRC, which may provide novel insights for the personalized treatment of CRC.

Pyrvinium pamoate inhibits cell proliferation through ROS-mediated AKT-dependent signaling pathway in colorectal cancer.

The use of the anthelmintic drug pyrvinium pamoate (PP) in cancer therapy has been extensively investigated in the last decade. PP has been shown to have an inhibitory effect in colorectal cancer (CRC), but the underlying mechanism remains elusive. We aimed to investigate the antitumor activity and mechanisms of PP in CRC. In the present study, we used CCK-8 assays, colony formation assays, and western blotting to reveal that PP effectively suppressed CRC cell proliferation and the AKT-dependent signaling pathway in a concentration-dependent and time-dependent manner. Flow cytometric analysis and fluorescence microscopy demonstrated that PP increased intracellular reactive oxygen species (ROS) accumulation. We found that the inhibitory effect of PP on cell proliferation and AKT protein expression induced by PP could be partially reversed by N-acetyl-L-cysteine (NAC), an ROS scavenger. In addition, the results also demonstrated that PP inhibited cell migration by modulating epithelial-to-mesenchymal transition (EMT)-related proteins, including E-cadherin and vimentin. In conclusion, our data suggested that PP effectively inhibited cell proliferation through the ROS-mediated AKT-dependent signaling pathway in CRC, further providing evidence for the use of PP as an antitumor agent.

Small molecule 2,3-DCPE induces S phase arrest by activating the ATM/ATR-Chk1-Cdc25A signaling pathway in DLD-1 colon cancer cells.

In our previous study, it was reported that 2[[3-(2,3-dichlorophenoxy)propyl]amino]ethanol (2,3-DCPE) induces apoptosis and cell cycle arrest. The current study aimed to investigate the molecular mechanism involved in 2,3-DCPE-induced S phase arrest. The results demonstrated that 2,3-DCPE upregulated phosphorylated (p-)H2A histone family member X, a biomarker of DNA damage, in the DLD-1 colon cancer cell line. Western blotting revealed that 2,3-DCPE increased the checkpoint kinase (Chk)1 (Ser317 and Ser345) level and decreased the expression of M-phase inducer phosphatase 1 (Cdc25A) in a time-dependent manner. Subsequently, the results demonstrated that the ataxia-telangiectasia mutated (ATM) and ataxia-telangiectasia and Rad3-related (ATR) inhibitors wortmannin and caffeine had no effect on the cell cycle; however, the inhibitors partially abrogated 2,3-DCPE-induced S phase arrest. Flow cytometry assays revealed that caffeine (2 mM) reduced the proportion of S phase cells from 83 to 39.6% and that wortmannin (500 nM) reduced the proportion of S phase cells from 83 to 48.2%. Furthermore, wortmannin and caffeine inhibited the 2,3-DCPE-mediated phosphorylation of Chk1 and the degradation of Cdc25A. However, these ATM/ATR inhibitors had limited effect on 2,3-DCPE-induced apoptosis. Taken together, the data of the current study indicated that 2,3-DCPE caused DNA damage in colon cancer cells and that 2,3-DCPE-induced S phase arrest was associated with the activation of the ATM/ATR-Chk1-Cdc25A pathway.

Diverse molecular functions of aspartate ß­hydroxylase in cancer (Review).

Aspartate/asparagine ß­hydroxylase (AspH) is a type II transmembrane protein that catalyzes the post­translational hydroxylation of definite aspartyl and asparaginyl residues in epidermal growth factor­like domains of substrates. In the last few decades, accumulating evidence has indicated that AspH expression is upregulated in numerous types of human malignant cancer and is associated with poor survival and prognosis. The AspH protein aggregates on the surface of tumor cells, which contributes to inducing tumor cell migration, infiltration and metastasis. However, small­molecule inhibitors targeting hydroxylase activity can markedly block these processes, both in vitro and in vivo. Immunization of tumor­bearing mice with a phage vaccine fused with the AspH protein can substantially delay tumor growth and progression. Additionally, AspH antigen­specific CD4+ and CD8+ T cells were identified in the spleen of tumor­bearing mice. Therefore, these agents may be used as novel strategies for cancer treatment. The present review summarizes the current progress on the underlying mechanisms of AspH expression in cancer development.

Identification of Four Pathological Stage-Relevant Genes in Association with Progression and Prognosis in Clear Cell Renal Cell Carcinoma by Integrated Bioinformatics Analysis.

Clear cell renal cell carcinoma (ccRCC) is a major histological subtype of renal cell carcinoma and can be clinically divided into four stages according to the TNM criteria. Identifying clinical stage-related genes is beneficial for improving the early diagnosis and prognosis of ccRCC. By using bioinformatics analysis, we aim to identify clinical stage-relevant genes that are significantly associated with the development of ccRCC. First, we analyzed the gene expression microarray data sets: GSE53757 and GSE73731. We divided these data into five groups by staging information-normal tissue and ccRCC stages I, II, III, and IV-and eventually identified 500 differentially expressed genes (DEGs). To obtain precise stage-relevant genes, we subsequently applied weighted gene coexpression network analysis (WGCNA) to the GSE73731 dataset and KIRC data from The Cancer Genome Atlas (TCGA). Two modules from each dataset were identified to be related to the tumor TNM stage. Several genes with high inner connection inside the modules were considered hub genes. The intersection results between hub genes of key modules and 500 DEGs revealed UBE2C, BUB1B, RRM2, and TPX2 as highly associated with the stage of ccRCC. In addition, the candidate genes were validated at both the RNA expression level and the protein level. Survival analysis also showed that 4 genes were significantly correlated with overall survival. In conclusion, our study affords a deeper understanding of the molecular mechanisms associated with the development of ccRCC and provides potential biomarkers for early diagnosis and individualized treatment for patients at different stages of ccRCC.

Tumor-suppressive function and mechanism of HOXB13 in right-sided colon cancer.

Right-sided colon cancer (RCC) and left-sided colon cancer (LCC) differ in their clinical and molecular features. An investigation of differentially expressed genes (DEGs) between RCC and LCC could contribute to targeted therapy for colon cancer, especially RCC, which has a poor prognosis. Here, we identified HOXB13, which was significantly less expressed in RCC than in LCC and associated with prognosis in RCC, by using 5 datasets from the Gene Expression Omnibus (GEO). Tissue sample analysis showed that HOXB13 was differentially expressed between normal and only RCC tumor tissues. HOXB13 inhibited colon cancer cell proliferation and induced apoptosis both in vitro and in vivo. Furthermore, we found that HOXB13 might be regulated by DNMT3B and suppress C-myc expression to exert antitumor effects via ß-catenin/TCF4 signals in RCC. In conclusion, the current study is the first to demonstrate that HOXB13 has a tumor-suppressive effect in RCC. High expression levels of HOXB13 are associated with prolonged overall survival in patients with RCC. The DNMT3B-HOXB13-C-myc signaling axis might be a molecular target for the treatment of RCC.

Weighted gene coexpression analysis indicates that PLAGL2 and POFUT1 are related to the differential features of proximal and distal colorectal cancer.

In the current era of precision medicine, there is a general consensus that the anatomical site is an important factor in the management of colorectal cancer (CRC). To investigate the underlying molecular mechanisms between proximal and distal CRC and to identify the responsible genes, we analyzed the gene expression patterns of colorectal tumors from two microarray datasets, GSE39582 and GSE14333, on the NCBI Gene Expression Omnibus and the RNA­seq data from TCGA. Weighted coexpression network analysis (WGCNA) was applied to construct a gene coexpression network. The red module in GSE39582 and the dark­gray module from the TCGA dataset were found to be highly correlated with the anatomical site of CRC. A total of 12 hub genes were found in two datasets, 2 of which PLAG1 like zinc finger 2 (PLAGL2) and protein O­fucosyltransferase 1 (POFUT1) were common and upregulated in tumor samples in CRC. The module with the highest correlation provided references that will help to characterize the difference between left­sided and right­sided CRC. The survival analysis of PLAGL2 and POFUT1 expression revealed differences between proximal and distal CRC. Gene set enrichment analysis based on those two genes provided similar results: GPI anchor biosynthesis and peroxisome and selenoamino acid metabolism. PLAGL2 and POFUT1, which have the highest correlation with tumor location, may serve as biomarkers and therapeutic targets for the precise diagnosis and treatment of CRC in the future.

Identification of key tumorigenesis­related genes and their microRNAs in colon cancer.

Colorectal cancer (CRC) is one of the most common malignant tumors and its development involves multi­gene driven processes that affect the digestive system. The objective of this study was to identify tumorigenesis­associated gene signatures using microarray expression profiling data. The gene expression profiling of GSE39582, a dataset containing 566 colon cancer samples and 19 non­tumoral colorectal mucosae was downloaded from Gene Expression Omnibus (GEO) database. A total of 439 differentially expressed genes (DEGs) were extracted by GEO2R. Many of these DEGs were cancer­related, involved in the regulation of cell proliferation, extracellular matrix (ECM)­receptor interaction and phosphatidylinositol 3­kinase (PI3K)­Akt signaling pathway according to the results of pathway enrichment analysis in Database for Annotation, Visualization and Integrated Discovery (DAVID). Then, 10 genes were predicted to play an important role in the development of CRC. Transient receptor potential cation channel, subfamily M, and member 6 (TRPM6), a member of 10 hub genes, was confirmed to be downregulated in 16 (80%) of 20 colon cancer tissues using quantitative polymerase chain reaction (qPCR) technology. Furthermore, high expression of TRPM6 was indicative of a prolonged overall survival (OS) in CRC patients through the analysis of GSE39582. Hsa­let­7g and hsa­let­7f­1 were believed to be the regulatory miRNAs of TRPM6 by TCGA and miRanda database. In conclusion, this study may play a critical role in promoting the discovery of potential targets for diagnosis, treatment and prognosis of CRC.

Lobaplatin suppresses proliferation and peritoneal metastasis of colorectal cancer in a preclinical model.

Peritoneal metastasis from colorectal cancer (CRC) is related to poor prognosis. Intraperitoneal chemotherapy is an efficient method to treat peritoneal metastasis (PM); however, the outcomes remain unsatisfactory. The present study aimed to investigate the antitumor activity of lobaplatin and its role in intraperitoneal chemotherapy. The findings showed that the proliferation of CRC was inhibited in a dose-dependent manner when DLD1 and HCT116 cells were treated with various concentrations of lobaplatin (0, 6.3, 12.5, 25, 50, and 100 µg/mL, respectively). Flow cytometry and Western blot analysis confirmed that lobaplatin affected CRC cells by inducing apoptosis and modulating the caspase family. In the animal study, nude mice were injected with DLD1 cells and divided into three groups. Lobaplatin was injected intraperitoneally to simulate intraperitoneal chemotherapy. Group A was the control group treated with PBS. Group B was injected with DLD1 and treated with lobaplatin simultaneously, while group C was treated with lobaplatin 1 week after cell injection. The results showed that group A harbored maximal tumors on the peritoneal surface, while group B had the least number (9.2 ± 1.3 and 0.4 ± 0.5, respectively P < 0.01). These findings indicated that lobaplatin suppressed the tumor growth as an intraperitoneal chemotherapy agent and achieved a satisfactory therapeutic effect at an early stage. Further blood test and tissue staining did not reveal any liver and kidney toxicity that was induced by lobaplatin. In conclusion, lobaplatin could be an effective and safe agent for CRC treatment, thereby commissioning a novel strategy in intraperitoneal chemotherapy for patients with peritoneal metastasis.

Variability in HER2 expression between primary colorectal cancer and corresponding metastases.

PURPOSE: This study aimed to investigate the HER2 status of primary colorectal cancer (CRC) and corresponding metastases, and determine the correlation between HER2 and clinicopathological characteristics. METHODS: We collected the clinicopathological features of 98 CRC patients and 66 patients which were previously evaluated for the KRAS status. The tissue samples of primary CRC tumors (n = 98), noninvolved colorectal mucosa (n = 98), paired lymph nodes (n = 98, 69 patients had positive metastatic nodes), and liver metastases (n = 22) were evaluated using immunohistochemistry for HER2. The kappa test was used to evaluate the concordance rate of HER2 status. Survival analysis was established according to the Kaplan-Meier method. RESULTS: HER2 overexpression was more common in primary tumors among the younger patients (P < 0.05). No survival significance was revealed in the HER2 status. The HER2-positive rate was 11.2% for the primary CRC tumors, 0% for the normal adjacent mucosa tissues, 10.1% for the matched positive lymph nodes, and 31.8% for the corresponding metastasis. Seven of sixty-nine cases (10.1%) exhibited biomarker discordance in nodal metastases compared with primary tumors (κ = 0.48, P < 0.05); 6 out of 22 cases (27.3%) exhibited biomarker discrepancy in liver metastases compared with primary tumors (κ = 0.32, P > 0.05). Compared with lymph nodes, HER2 overexpression in the primary tissue was more common in KRAS wild-type patients (P < 0.05). CONCLUSIONS: The present study showed a high rate of discordance in matched pairs of primary tumors and metastases, suggesting that the accurate evaluation of HER2 status is essential before any therapeutic decision.

Identification of candidate genes and long non-coding RNAs associated with the effect of ATP5J in colorectal cancer.

The incidence and development of colorectal cancer (CRC) is a process with multiple gene interactions. We have previously demonstrated that ATP synthase-coupling factor 6, mitochondrial (ATP5J) is associated with CRC migration and 5-fluorouracil resistance; nevertheless, the exact molecular mechanism remains unclear. The following study uses microarray and bioinformatics methods to identify candidate genes and long non-coding RNAs (lncRNAs) in CRC cells (two pairs) with upregulated and downregulated ATP5J. Briefly, a total of 2,190 differentially expressed mRNAs (DEmRNAs) were sorted. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed for 4 DEmRNAs to validate the results of microarray analysis. Functional annotation and pathway enrichment were analyzed for DEmRNAs using the Database for Annotation, Visualization and Integrated Discovery. Significantly enriched pathways included the regulation of gene expression and cell growth. The protein­protein interaction network was constructed, and AKT serine/threonine kinase 2 (AKT2) was considered as one of the hub genes. For further analysis, 51 DEmRNAs and 30 DElncRNAs were selected that were positively or negatively associated with the expression of ATP5J in the two cell pairs. X-inactive specific transcript (XIST), premature ovarian failure 1B (POF1B) and calmin (CLMN) were identified in the DEmRNA-DElncRNA co-expression network. The expression of AKT2 and XIST in CRC cells was confirmed by RT-qPCR. To sum up, the candidate genes and lncRNAs, as well as potential signaling pathways, which were identified using integrated bioinformatics analysis, could improve the understanding of molecular events involved in the function of ATP5J in CRC.

Mutations in KRAS codon 12 predict poor survival in Chinese patients with metastatic colorectal cancer.

KRAS mutations serve a function in tumorigenesis of colorectal cancer (CRC) and guide the use of targeted drugs. However, the prognostic value of KRAS mutations and their subtypes remain controversial. The present study aimed to investigate the correlations between KRAS mutations and clinicopathological characteristics, and their prognostic significance in Chinese patients with metastatic CRC (mCRC). A total of 135 patients with mCRC were analyzed for KRAS mutations. Mutations in codon 12 and 13 were identified in 45 (33.3%) patients. Only 3 patients harbored a mutation of V600E. Compared with male patients, KRAS codon 12 mutations were more common in female patients (P<0.05). KRAS codon 13 mutations tended to arise in right-sided compared with left-sided colon cancer (P<0.05). Survival analysis was performed in 101 patients receiving primary tumor resection. Compared with KRAS codon 12 wild-type, codon 12 mutations were markedly correlated with a poorer survival (log-rank P=0.002). No prognostic significance was revealed in codon 13 mutations. In univariate analysis, mortality risk was significantly increased by subtypes of G12D and G12V [hazard ratio (HR) =2.313, 95% confidence interval (CI) =1.069-5.004, P=0.03; HR=2.621, 95% CI=1.057-6.497, P=0.04, respectively]. The results of the present study suggested that codon 12 mutations, in particular G12D and G12V, predicted a negative prognosis in Chinese patients with mCRC. These findings require further confirmation via prospective studies with larger samples.