The impact of SARS-Cov-2 Omicron infection on short-term outcomes after elective surgery in patients with gastrointestinal cancer.

With the emergence of novel variants, Omicron variant caused a different clinical picture than the previous variants and little evidence was reported regarding perioperative outcomes after Omicron variants. The aim of the study was to evaluate the postoperative outcomes of gastrointestinal cancer patients following Omicron variants infection and also to determine the timing of surgery after infection recovery. A total of 124 patients who underwent gastrointestinal cancer surgery with prior SARS-CoV-2 infection between December 2022 and February 2023 were retrospectively reviewed. 174 cases underwent the same operation during December 2018 and February 2019 as control group. SARS-CoV-2-infected patients were further categorized into three groups based on infected time (1-3 weeks; 4-6 weeks; and ≥ 7 weeks). 90.3% of SARS-CoV-2-infected patients had mild symptoms. The COVID-19 vaccination rate was 71.0%, with a full vaccination rate of 48.4%. There were no significant differences in 30-day morbidity and mortality. There was also no significant difference in pulmonary complications, cardiovascular complications, and surgical complications between the three different diagnosis time groups. In conclusion, reducing waiting time for elective surgery was safe for gastrointestinal cancer patients in the context of an increased transmissibility and milder illness severity with Omicron variant.

Integration of machine learning for developing a prognostic signature related to programmed cell death in colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) presents a significant global health burden, characterized by a heterogeneous molecular landscape and various genetic and epigenetic alterations. Programmed cell death (PCD) plays a critical role in CRC, offering potential targets for therapy by regulating cell elimination processes that can suppress tumor growth or trigger cancer cell resistance. Understanding the complex interplay between PCD mechanisms and CRC pathogenesis is crucial. This study aims to construct a PCD-related prognostic signature in CRC using machine learning integration, enhancing the precision of CRC prognosis prediction. METHOD: We retrieved expression data and clinical information from the Cancer Genome Atlas and Gene Expression Omnibus (GEO) datasets. Fifteen forms of PCD were identified, and corresponding gene sets were compiled. Machine learning algorithms, including Lasso, Ridge, Enet, StepCox, survivalSVM, CoxBoost, SuperPC, plsRcox, random survival forest (RSF), and gradient boosting machine, were integrated for model construction. The models were validated using six GEO datasets, and the programmed cell death score (PCDS) was established. Further, the model's effectiveness was compared with 109 transcriptome-based CRC prognostic models. RESULT: Our integrated model successfully identified differentially expressed PCD-related genes and stratified CRC samples into four subtypes with distinct prognostic implications. The optimal combination of machine learning models, RSF + Ridge, showed superior performance compared with traditional methods. The PCDS effectively stratified patients into high-risk and low-risk groups, with significant survival differences. Further analysis revealed the prognostic relevance of immune cell types and pathways associated with CRC subtypes. The model also identified hub genes and drug sensitivities relevant to CRC prognosis. CONCLUSION: The current study highlights the potential of integrating machine learning models to enhance the prediction of CRC prognosis. The developed prognostic signature, which is related to PCD, holds promise for personalized and effective therapeutic interventions in CRC.

Inhibition of OTUB2 suppresses colorectal cancer cell growth by regulating ß-Catenin signaling.

In the effort to identify deubiquitinating enzymes required for the growth of colorectal cancer (CRC) cells, we found that OTUB2 knockdown markedly inhibited the viability of these cancer cells in culture and in xenografted mice. It was also found that the level of OTUB2 was elevated in primary CRCs, and its high expression was a poor prognostic indicator for the patients. Interestingly, immunoprecipitation and LC-MS/MS analyses suggested that ß-Catenin was an OTUB2-interacting protein, and there was a positive correlation between OTUB2 and ß-Catenin expression in both CRC tissues and cell lines. We then performed reciprocal co-immunoprecipitations and demonstrated that OTUB2 and ß-Catenin bound to each other. Enforced expression of OTUB2 decreased ubiquitination of ß-Catenin and increased the half-life and intracellular level of ß-Catenin, whereas the catalytic inactive OTUB2 did not. OTUB2 also enhanced ß-Catenin-mediated transactivation as measured by TCF-luciferase and expression of endogenous CCND1 and MYC in CRC cells. These results indicated that OTUB2 was a potential target for therapeutic intervention for CRC.

Application of a New Retraction Method in Laparoscopic Gastrectomy for Gastric Cancer.

BACKGROUND: Better exposition is important for lymph node dissection in the suprapancreatic region and lesser curvature region of the stomach, and digestive tract reconstruction, especially without excellent assistants. PATIENTS AND METHODS: We developed a new laparoscopic retraction method with the use of two internal retractors (TIRs) punctured along with suture. Clinicopathological data, surgical data, and postoperative outcomes were assessed. RESULTS: Of the 143 patients included, 51 underwent surgery with the double-sling suture method and 92 underwent surgery with the TIRs method. Laparoscopic radical gastrectomy was successfully performed in all patients. There were no significant differences in patient characteristics or preoperative data in the 2 groups. The operative time was significantly shorter in the TIR group, but the amount of bleeding did not differ. No retraction-related complications both in clipped tissue and liver occurred in all patients. CONCLUSIONS: Our new retraction technique provided an optimal surgical field and make surgery lower requirements for assistants.

Improvement of esophagojejunostomy technique after total gastrectomy with overlap method: reduce the difficulty of surgery and shorten operation time.

Gastric cancer (GC) is one of the most malignant human cancers. Totally laparoscopic total gastrectomy (TLTG) is a difficult operation, especially esophagojejunostomy. Our team has adopted the method of suspending and pulling the esophagus with the visceral retractor and two needles of barbed wire interlocking to suture the common opening, which reduces the difficulty of the operation. From January to December 2020, 20 patients underwent TLTG with the overlap method by improved esophagojejunostomy technique and 20 patients with the traditional overlap method after TLTG were used as the control group. The surgery was performed using a five-trocar system. After lymphadenectomy, the esophagus was separated at least 2 cm from the upper edge of the tumor. Improved esophagojejunostomy technique was completed by the following steps: (1) cutting end of the esophagus suspension; (2) jejuno-jejunostomy; (3) esophagojejunostomy; (4) close the esophagojejunum common incision opening. The results showed that the operative time, and anastomosis time of the modified group were shorter than those of the traditional group, There were no postoperative complications such as anastomotic leakage, anastomotic stenosis, duodenal stump fistula and Roux stasis syndrome in the both group. There was no statistically significant difference in postoperative complications between the two groups. Taken together, our modified esophagojejunostomy technique after total gastrectomy is feasible and safe. This procedure is an efficient method to shorten the operation time and reduce the difficulty of surgery in esophagojejunostomy of laparoscopic total gastrectomy.

Comparison of [68Ga]Ga-DOTA-FAPI-04 and [18F]FDG PET/MRI in the Preoperative Diagnosis of Gastric Cancer.

Purpose: Our objective was to compare the value of positron emission tomography/magnetic resonance imaging (PET/MRI) with the new imaging agent [68Ga]Ga-DOTA-FAPI-04 and the traditional imaging agent [18F]FDG for the preoperative diagnosis of gastric cancer. Methods: Forty patients with gastric cancer diagnosed by gastroscopy in gastrointestinal surgery at our hospital from June 2020 to January 2021 were analyzed. All patients underwent simultaneous [68Ga]Ga-DOTA-FAPI-04 and [18F]FDG PET/MRI. The standard uptake value (SUV), fat removal standard uptake value (SUL), and diagnostic sensitivity, specificity, and accuracy for primary and metastatic lesions were compared, and their diagnostic value for different lymph node dissection stages was analyzed. Results: The median age of the patients in this cohort was 68 years. Twenty-nine patients underwent surgery, and 11 patients underwent gastroscopic biopsy. The SUVmax of primary lesions in the FDG group and the FAPI group was 5.74 ± 5.09 and 8.06 ± 4.88, respectively (P < 0.01); SULmax values were 3.52 ± 2.80 and 5.64 ± 3.25, respectively (P < 0.01). The SUVmax of metastases in the two groups was 3.81 ± 3.08 and 5.17 ± 2.80, respectively (P < 0.05). The diagnostic sensitivities for primary lesions in the FDG group and the FAPI group were 0.72 and 0.94, respectively (P < 0.05). Combined with postoperative pathological staging, there was no difference in diagnostic sensitivity and specificity of lymph node staging between the FDG and FAPI groups (P > 0.05). Conclusion: Compared with the traditional imaging agent, [68Ga]Ga-DOTA-FAPI-04 has better diagnostic efficiency but no substantial advantage for preoperative lymph node staging.

Assessment of Autologous Blood marker localIzation and intraoperative coLonoscopy localIzation in laparoscopic colorecTal cancer surgery (ABILITY): a randomized controlled trial.

BACKGROUND: Laparoscopic colorectal surgery has been proved to have similar oncological outcomes with open surgery. Due to the lack of tactile perception, surgeons may have misjudgments in laparoscopic colorectal surgery. Therefore, the accurate localization of a tumor before surgery is important, especially in the early stages of cancer. Autologous blood was thought a feasible and safe tattooing agent for preoperative endoscopic localization but its benefits remain controversial. We therefore proposed this randomized trial to the accuracy and safety of autogenous blood localization in small, serosa-negative lesion which will be resected by laparoscopic colectomy. METHODS: The current study is a single-center, open-label, non-inferiority, randomized controlled trial. Eligible participants would be aged 18-80 years and diagnosed with large lateral spreading tumors that could not be treated endoscopically, malignant polyps treated endoscopically that required additional colorectal resection, and serosa-negative malignant colorectal tumors (≤ cT3). A total of 220 patients would be randomly assigned (1:1) to autologous blood group or intraoperative colonoscopy group. The primary outcome is the localization accuracy. The secondary endpoint is adverse events related to endoscopic tattooing. DISCUSSION: This trial will investigate whether autologous blood marker achieves similar localization accuracy and safety in laparoscopic colorectal surgery compared to intraoperative colonoscopy. If our research hypothesis is statistically proved, the rational introduction of autologous blood tattooing in preoperative colonoscopy can help improve identification of the location of tumors for laparoscopic colorectal cancer surgery, performing an optimal resection, and minimizing unnecessary resections of normal tissues, thereby improving the patient's quality of life. Our research data will also provide high quality clinical evidence and data support for the conduction of multicenter phase III clinical trials. TRIAL REGISTRATION: This study is registered with ClinicalTrials.gov, NCT05597384. Registered 28 October 2022.

Quality and accuracy of gastric cancer related videos in social media videos platforms.

BACKGROUND: Gastric cancer is a major public health problem worldwide. Social media has affected public's daily lives in ways no one ever thought possible. Both TikoTok and its Chinese version Douyin are the most popular short video posting platform. This study aimed to evaluate the quality, accuracy, and completeness of videos for gastric cancer on TikTok and Douyin. METHODS: The terms "gastric cancer" was searched on TikTok in both English and Japanese, and on Douyin in Chinese. The first 100 videos in three languages (website's default setting) were checked. QUality Evaluation Scoring Tool (QUEST) and DISCERN as the instrument for assessing the quality of the information in each video. Content was analysed under six categories (aetiology, anatomy, symptoms, preventions, treatments, and prognosis). The educational value and completeness were evaluated with a checklist developed by the researchers. RESULTS: A total of 78 videos in English, 63 in Japanese, and 99 in Chinese were analyzed. The types of sources were as follows: 6.4% in English, 4.8% in Japanese, and 57.6% in Chinese for health professionals; 93.6% in English, 95.2% in Japanese, and 3.0% in Chinese for private users; none in English and Japanese, but 39.4% in Chinese for other sources. In all, 20.5% in English, 17.5% in Japanese, and 93.9% in Chinese of videos had useful information about gastric cancer. Among the useful videos, the videos published in Chinese had the highest QUEST(p < 0.05) and DISCERN scores(p < 0.05), followed by those published in Japanese. Among the educational videos, prognosis in English (37.5%), symptoms in Japanese (54.5%), and prevention in Chinese (47.3%) were the most frequently covered topic. CONCLUSIONS: TikTok in English and Japanese might not fully meet the gastric cancer information needs of public, but Douyin in Chinese was the opposite.

The Modified Glasgow Prognostic Score Predicts Survival in Gastric Cancer Patients with Normal CEA and CA19-9.

Background: Traditionally, serum CEA and CA19-9 levels are good prognostic factors for gastric cancer. Many gastric cancer patients do not have elevated CEA or CA19-9 levels even at a very advanced stage. This study investigates the significance of the modified Glasgow prognostic score (mGPS) for the survival of gastric cancer patients with normal CEA and CA19-9. Methods: We retrospectively examined 488 curatively resected gastric cancer patients with normal preoperative serum levels of CEA and CA19-9 to evaluate the prognostic ability of mGPS for overall survival. The prognostic significance was analyzed by univariate and multivariate analyses. Results: Age, hemoglobin, white cell count, and neutrophils were each significantly correlated with the mGPS. Multivariate analyses showed that tumor location (HR, 0.803; 95% CI, 0.667-0.966; P=0.020), TNM stage (HR, 2.714; 95% CI, 2.250-3.275; P < 0.001), and mGPS (HR, 1.042; 95% CI, 1.105-1.772; P=0.023) were significantly associated with overall survival. Significant correlations were found between overall survival and mGPS. The Kaplan-Meier analysis demonstrated significant differences among patients with mGPS of 0, 1, and 2 (P < 0.001), with the mortality rate being higher for patients with a higher mGPS. Conclusion: The mGPS can predict survival in gastric cancer patients with normal CEA and CA19-9.

SHMT2 Drives the Progression of Colorectal Cancer by Regulating UHRF1 Expression.

INTRODUCTION: Serine hydroxymethyltransferase 2 (SHMT2) has a critical role in serine-glycine metabolism to drive cancer cell proliferation. Yet, the function of SHMT2 in tumorigenesis, especially in human colorectal cancer (CRC) progression, remains largely unclear. MATERIALS AND METHODS: CRC and paired normal samples were collected in the Department of Colorectal Surgery, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, and assessed by real-time polymerase chain reaction (qPCR) analysis, western blot (WB), and immunohistochemistry (IHC). Moreover, SHMT2 expression in human CRC cells was identified by qPCR and WB. The CRC cell proliferation, migration, and invasion after SHMT2 knockdown were explored through in vitro and in vivo assays. mRNA-seq assays were used to investigate the underlying mechanisms behind the SHMT2 function. RESULTS: It was found that SHMT2 mRNA and protein were overexpressed in CRC tissue compared to the levels in normal mucosa. Positive expression of SHMT2 was significantly correlated with TNM stage and lymph node metastasis, and elevated expression of SHMT2 resulted as an independent prognostic factor in patients with CRC. SHMT2 knockdown impaired the proliferation of CRC in vitro and in vivo and induced cell cycle arrest by regulating UHRF1 expression. CONCLUSION: Taken together, our findings reveal that UHRF1 is a novel target gene of SHMT2, which can be used as a potential therapeutic strategy for CRC therapy.

Ubiquitin specific peptidase 5 regulates colorectal cancer cell growth by stabilizing Tu translation elongation factor.

Ubiquitin specific peptidase 5 (USP5) is a ubiquitous expressed deubiquitinating enzyme (DUB). It has been shown involved in DNA repair, apoptosis, inflammation, and tumor cell growth. However, the function and molecular mechanism of USP5 in colorectal cancer (CRC) are still unclear. In the present study, we asked how it affected the growth of colorectal cancer cells. Methods: A shRNA-based high-content screening was performed to identify DUBs affecting the growth of CRC cells. CCK-8 assay and xenografts were used to assess CRC cell growth, survival and tumorigenesis. RT-qPCR, immunoblotting and immunohistochemistry were carried out to quantitate USP5 expression in CRC tissues and cell lines. Immunoprecipitation and mass spectrometry analysis were performed to identify USP5-interacting proteins. Cycloheximide chase was performed to assess Tu translation elongation factor (TUFM) stability. Dual luciferase reporter assay was utilized for USP5 promoter analysis. Results: We found that USP5 was highly expressed in a group of primary CRC tissues, and the increased USP5 was correlated with clinical stages and shorter overall survival. While USP5 knockdown effectively inhibited CRC cell growth, overexpressed USP5 promoted the growth of CRC cells and made them more resistant to doxorubicin (DOX). TUFM was discovered as a substrate of USP5. USP5 deubiquitinated TUFM and increased its level in CRC cells. Enforced expression of TUFM was able to alleviate the growth inhibition induced by USP5 knockdown. Further analyses showed that EBF transcription factor 1 (EBF1) was a major regulator for USP5 transcription, and DOX inhibited EBF1-USP5-TUFM axis in CRC cells. Conclusions: USP5 was required for CRC cells and promoted their growth and resistance to chemotherapeutics. TUFM was a USP5 deubiquitinating substrate that mediated the cellular effects of USP5. The transcription of USP5 was regulated by EBF1. Thus, targeting EBF1-USP5-TUFM axis is a potential novel strategy for CRC treatment.

Reduced Frequency and Prognostic Significance of Ring Finger Protein 43 Nucleotide Polymorphisms in a Chinese Colorectal Cancer Cohort.

The aim of this research was to verify the mutation rate of the ring finger protein 43 (RNF43) of the transmembrane E3 ubiquitin ligase and investigate the influence of single nucleotide polymorphisms (SNPs) rs2257205 in RNF43 in a Chinese colorectal cancer (CRC) cohort. DNA from 177 diagnosed CRC patients' tissues or blood samples were extracted, amplified, and sequenced. Clinicopathological features, including age, gender, tumor location, tumor-lymph node-metastasis stage, and survival information, were analyzed. Four novel RNF43 mutations (including G659 and R117 sites) were validated in 177 CRC patients; all events were somatic frameshift mutations. Furthermore, we also found that an SNP (rs2257205) of the RNF43 X117 site was associated with overall survival (OS) instead of disease-free survival. G homozygote subjects were significantly correlated with poor OS compared with another group. Then we rescued RNF43 R117R (encoded by nucleotide CGC) and R117H (encoded by nucleotide CAC) expression in the HCT116 cells and analyzed the targets of the Wnt/ß-catenin pathway. The expression of CCND1 and c-Myc were decreased. The prognosis of CRC patients could be affected by the different functions of SNPs of RNF43.

Publisher Correction: Deacetylation of serine hydroxymethyl-transferase 2 by SIRT3 promotes colorectal carcinogenesis.

The original version of this Article contained an error in the Data Availability Statement. The accession code indicated '53V' and should have read '5X3V'. This has been corrected in both PDF and HTML versions of the Article.

Inhibition of Ubiquitin Specific Protease 1 Sensitizes Colorectal Cancer Cells to DNA-Damaging Chemotherapeutics.

Mutations and altered expression of deubiquitinating enzymes (DUBs) have been found associated with many human diseases including cancers. In this study, Ubiquitin specific protease 1 (USP1) expression was found significantly increased in some colorectal cancers (CRC). The elevated USP1 level was associated with short overall survival of patients and with advanced stages of cancers. In cultured CRC cells, knockdown of USP1 induced growth arrest at G2/M of cell cycle and reduced the expression of anti-apoptotic proteins Bcl-2 and Mcl-1. Its knockdown also led to reduction of DNA-repair related substrates FANCD2 and ID1. Further investigations found that small molecular inhibitor of USP1 ML323 sensitized CRC cells to DNA-targeting chemotherapeutics, including doxorubicin, TOPI/II inhibitors, and PARP inhibitor, but not to 5-Fu. These results indicate that USP1 plays a critical in colorectal cancer cell survival and is a promising target for anti-colorectal cancer chemotherapy. Targeting USP1 may represent an effective strategy to regulate the DNA-repairing system.

Deacetylation of serine hydroxymethyl-transferase 2 by SIRT3 promotes colorectal carcinogenesis.

The conversion of serine and glycine that is accomplished by serine hydroxymethyltransferase 2 (SHMT2) in mitochondria is significantly upregulated in various cancers to support cancer cell proliferation. In this study, we observed that SHMT2 is acetylated at K95 in colorectal cancer (CRC) cells. SIRT3, the major deacetylase in mitochondria, is responsible for SHMT2 deacetylation. SHMT2-K95-Ac disrupts its functional tetramer structure and inhibits its enzymatic activity. SHMT2-K95-Ac also promotes its degradation via the K63-ubiquitin-lysosome pathway in a glucose-dependent manner. TRIM21 acts as an E3 ubiquitin ligase for SHMT2. SHMT2-K95-Ac decreases CRC cell proliferation and tumor growth in vivo through attenuation of serine consumption and reduction in NADPH levels. Finally, SHMT2-K95-Ac is significantly decreased in human CRC samples and is inversely associated with increased SIRT3 expression, which is correlated with poorer postoperative overall survival. Our study reveals the unknown mechanism of SHMT2 regulation by acetylation which is involved in colorectal carcinogenesis.

Lysyl oxidase-like 2 is highly expressed in colorectal cancer cells and promotes the development of colorectal cancer.

Colorectal cancer (CRC) is the third most common type of cancer. In the present study, the expression and intracellular localization of lysyl oxidase-like 2 (LOXL2) protein in CRC were examined. Quantitative polymerase chain reaction and western blot analysis of LOXL2 mRNA and protein expression was performed for 40 pairs of CRC tumor and normal mucosa tissue samples. The immunohistochemical staining of tissue microarrays was performed to detect LOXL2 protein expression. LOXL2 was highly expressed in the extracellular matrix and CRC cells. The positive expression of LOXL2 in CRC cells was significantly associated with the tumor tumor-node metastasis stage and distant metastasis, while elevated LOXL2 expression within the CRC cells was an independent prognostic factor in patients with CRC. The knockdown of LOXL2 impaired the proliferative and migratory abilities of CRC cells in vitro and in vivo, and induced cell cycle arrest and apoptosis. These findings indicated that LOXL2 might have an important role in CRC.

Reduced Risk of Inflammatory Bowel Disease-associated Colorectal Neoplasia with Use of Thiopurines: a Systematic Review and Meta-analysis.

BACKGROUND AND AIMS: The association between thiopurines and colorectal neoplasia risk remains controversial in inflammatory bowel disease [IBD] patients. We performed a systematic review and meta-analysis examining this association. METHODS: A comprehensive search of the PubMed, EMBASE and Cochrane Library databases was performed to identify relevant literature. Random-effects models were applied to calculate the pooled odds ratio [OR] and relative risk [RR] with corresponding 95% confidence intervals [CIs] among case-control and cohort studies. RESULTS: Eleven cohort and 16 case-control studies involving 95397 patients were included in this study. Overall, the use of thiopurines was associated with a reduced risk of colorectal neoplasia both in case-control [OR = 0.49, 95% CI: 0.34-0.70] and cohort studies [RR = 0.96, 95% CI: 0.94-0.98]. Moreover, a protective effect of thiopurines against advanced neoplasia [high-grade dysplasia and cancer] [OR = 0.51, 95% CI: 0.31-0.84 for case-control studies; RR = 0.96, 95% CI: 0.94-0.98 for cohort studies] and colorectal cancer [CRC] [OR = 0.56, 95% CI: 0.34-0.93 for case-control studies; RR = 0.96, 95% CI: 0.94-0.98 for cohort studies] was also observed. Furthermore, when the analysis was conducted on patients at a high risk for colorectal neoplasia, the chemopreventive effect was confirmed in patients with long disease duration [> 8 years] but not in those with extensive colitis or primary sclerosing cholangitis. CONCLUSIONS: This study demonstrated that thiopurine use was associated with a reduced risk of colorectal neoplasia, advanced neoplasia and CRC in IBD patients, especially those with long disease duration [> 8 years].

Ring finger protein 152 inhibits colorectal cancer cell growth and is a novel prognostic biomarker.

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in the world. RING finger-related E3 ubiquitin ligases play a role in tumorigenesis and can function either as oncogenes or tumor suppressors based on their target proteins. Here, we show that the expression of RNF152, a ring finger protein, in CRC tissues was significantly reduced compared with adjacent non-cancerous tissues. High expression levels of RNF152 correlated with better prognosis in patients with colorectal cancer. Low expression of RNF152 correlated with lymphatic metastasis. Overexpression of RNF152 inhibited CRC cell proliferation both in vitro and in vivo by inactivating the mechanistic target of rapamycin complex 1 (mTORC1) and inducing autophagy and apoptotic cell death. This strong inhibition was dependent on the E3 ligase activity of RNF152. Ectopic expression of the RNF152-CS-mutant, which lacks E3 ligase activity, significantly restored the proliferation ability of CRC cells. Our findings showed that RNF152 inhibits colorectal cancer growth and may be a novel prognostic biomarker for the treatment of CRC.

Aberrant KLK4 gene promoter hypomethylation in pediatric hepatoblastomas.

DNA methylation has a crucial role in cancer biology and has been recognized as an activator of oncogenes and inactivator of tumor suppressor genes, both of which are mechanisms for tumorigenesis. Kallikrein-related peptidase 4 (KLK4), has been suggested to be an oncogene in various types of cancer. The aim of the present study was to assess the DNA methylation patterns of the KLK4 gene in cancerous samples harvested from patients with hepatoblastoma (HB). KLK4 mRNA expression levels were detected using reverse transcription-quantitative polymerase chain reaction and assessed its DNA methylation patterns using high-throughput mass spectrometry on a matrix-assisted laser desorption/ionization time-of-flight mass array. A total of 10 HB and 10 normal liver tissue samples were obtained from patients with HB. The results of the present study showed that a significantly higher level of KLK4 mRNA expression levels were detected in HB tissues, as compared with the matched controls. Furthermore, the KLK4 gene promoter region was distinctively less methylated in the HB samples compared with the controls and negatively correlated with KLK4 mRNA expression levels. These findings indicate that aberrant methylation of KLK4 may contribute to its upregulated mRNA expression in HB.

Phosphorylase kinase ß affects colorectal cancer cell growth and represents a novel prognostic biomarker.

PURPOSE: To study the expression and intracellular localization of phosphorylase kinase ß (PHKß) protein in colorectal cancers (CRCs), analyze its correlation with clinicopathological features and prognosis, and study the biological roles and mechanism-of-action of PHKß in CRC cell lines. METHODS: Quantitative polymerase chain reaction (qPCR) and western blot assays were performed to compare the expressions of PHKß mRNA and protein in CRC tissues and matched normal mucosa. Tissue microarrays and immunohistochemical staining were performed to detect the expression and intracellular location of PHKß protein and analyze its correlation with the clinicopathological characteristics and prognosis in CRC patients. Proliferation, cell cycle, wound healing, and xenograft models were used to elucidate the potential role of PHKß in vitro and in vivo. RESULTS: PHKß mRNA and protein were found to be overexpressed in CRC tissue compared to the levels in normal mucosa. Positive expression of PHKß was significantly correlated with TNM stage and distal metastasis, and elevated expression of PHKß was an independent prognostic factor in patients with CRC. PHKß knockdown impaired proliferation of CRC in vitro and in vivo and induced cell cycle arrest. CONCLUSIONS: PHKß affects CRC cell growth and represents a novel prognostic biomarker.