Liquid biopsy: Precise diagnosis and therapy for cholangiocarcinoma.

The following letter to the editor highlights the review titled "Liquid biopsy in cholangiocarcinoma: Current status and future perspective" in World J Gastrointest Oncol 2021; 13: 332-350. It is necessary to realize individualized therapy to improve the clinical prognosis of patients with cholangiocarcinoma.

Photodynamic therapy: A next alternative treatment strategy for hepatocellular carcinoma?

Liver cancer is one of the most common cancers in the world. Of all types of liver cancer, hepatocellular carcinoma (HCC) is known to be the most frequent primary liver malignancy and has seriously compromised the health status of the general population. Locoregional thermal ablation techniques such as radiofrequency and microwave ablation, have attracted attention in clinical practice as an alternative strategy for HCC treatment. However, their aggressive thermal effect may cause undesirable complications such as hepatic decompensation, hemorrhage, bile duct injury, extrahepatic organ injuries, and skin burn. In recent years, photodynamic therapy (PDT), a gentle locoregional treatment, has attracted attention in ablation therapy for patients with superficial or luminal tumors as an alternative treatment strategy. However, some inherent defects and extrinsic factors of PDT have limited its use in clinical practice for deep-seated HCC. In this contribution, the aim is to summarize the current status and challenges of PDT in HCC treatment and provide potential strategies to overcome these deficiencies in further clinical translational practice.

Mechanism of dynamic near-infrared fluorescence cholangiography of extrahepatic bile ducts and applications in detecting bile duct injuries using indocyanine green in animal models.

Fluorescence intraoperative cholangiography (IOC) is a potential alternative for identifying anatomical variation and preventing iatrogenic bile duct injuries by using the near-infrared probe indocyanine green (ICG). However, the dynamic process and mechanism of fluorescence IOC have not been elucidated in previous publications. Herein, the optical properties of the complex of ICG and bile, dynamic fluorescence cholangiography and iatrogenic bile duct injuries were investigated. The emission spectrum of ICG in bile peaked at 844 nm and ICG had higher tissue penetration. Extrahepatic bile ducts could fluoresce 2 min after intravenous injection, and the fluorescence intensity reached a peak at 8 min. In addition, biliary dynamics were observed owing to ICG excretion from the bile ducts into the duodenum. Quantitative analysis indicated that ICG-guided fluorescence IOC possessed a high signal to noise ratio compared to the surrounding peripheral tissue and the portal vein. Fluorescence IOC was based on rapid uptake of circulating ICG in plasma by hepatic cells, excretion of ICG into the bile and then its interaction with protein molecules in the bile. Moreover, fluorescence IOC was sensitive to detect bile duct ligation and acute bile duct perforation using ICG in rat models. All of the results indicated that fluorescence IOC using ICG is a valid alternative for the cholangiography of extrahepatic bile ducts and has potential for measurement of biliary dynamics.

Mechanism of Dynamic Near-infrared Fluorescence Cholangiography of Extrahepatic Bile Ducts and Applications in Detecting Bile Duct Injuries Using Indocyanine Green in Animal Models / 华中科技大学学报（医学）（英德文版）

Fluorescence intraoperative cholangiography (IOC) is a potential alternative for identifying anatomical variation and preventing iatrogenic bile duct injuries by using the near-infrared probe indocyanine green (ICG).However,the dynamic process and mechanism of fluorescenceIOC have not been elucidated in previous publications.Herein,the optical properties of the complex of ICG and bile,dynamic fluorescence cholangiography and iatrogenic bile duct injuries were investigated.The emission spectrum of ICG in bile peaked at 844 nm and ICG had higher tissue penetration.Extrahepatic bile ducts could fluoresce 2 min after intravenous injection,and the fluorescence intensity reached a peak at 8 min.Inaddition,biliary dynamics were observed owing to ICG excretion from the bile ducts into the duodenum.Quantitative analysis indicated that ICG-guided fluorescence IOC possessed a high signal to noise ratio compared to the surrounding peripheral tissue and the portal vein.Fluorescence IOC was based on rapid uptake of circulating ICG in plasma by hepatic cells,excretion of ICG into the bile and then its interaction with protein molecules in the bile.Moreover,fluorescence IOC was sensitive to detect bile duct ligation and acute bile duct perforation using ICG in rat models.All of the results indicated that fluorescence IOC using ICG is a valid alternative for the cholangiography of extrahepatic bile ducts and has potential for measurement of biliary dynamics.

Tumor suppressor TSLC1 inhibits growth, proliferation, invasiveness and angiogenesis in nude mice xenografted tumor of Eca109 cells.

Tumor suppressor in lung cancer 1 (TSLC1) is a novel tumor suppressor gene whose inactivation is implicated in the occurrence, invasion, metastasis and prognosis of esophageal cancer. TSLC1 was studied by comparing the tumor formation of TSLC1 transfectant and control cells in nude mice. Compared with blank group and mock group, tumor size and infiltrating range of transfected group was less, differentiation of tumor tissue was slightly better, and differences of tumor angiogenesis was worse. There was no obvious difference between blank group and mock group. We have shown TSLC1 gene inhibited the growth proliferation, infiltration and angiogenesis of Eca109 cells.

Effect of TSLC1 gene on growth and apoptosis in human esophageal carcinoma Eca109 cells.

INTRODUCTION: To explore the effect of tumor suppressor in lung cancer 1 (TSLC1) on proliferation and apoptosis in esophageal cancer Eca109 cells. MATERIAL AND METHODS: Eca109 cells were divided into three groups: TSLC1 transfected group (TTG), mock group (MG) and untransfected group (UTG). The TTG and MG were transfected transiently with the pIRES2-EGFP-TSLC1 eukaryotic expression vector and pIRES2-EGFP vector respectively. The UTG was a blank control. The TSLC1 expression in TTG was analyzed with the fluorogram and RT-PCR method. Cell proliferation was measured with 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium (MTT) assay. Cell cycle was measured by flow cytometry (FCM). Cell apoptosis was detected by Annexin-V/PI double staining FCM. RESULTS: Green color was found in TTG and MG. The band of TSLC1 mRNA of TTG was located at about 1400 bp by RT-PCR and agarose gel electrophoresis assay. The TSLC1 inhibited cell proliferation significantly in MTT assay, and the cell proliferation was slower in TTG than MG and UTG. After TSLC1 transfection, cell numbers increased in G0/G1 phase and decreased in S phase. Forty-eight hours after transfection, the apoptosis rate and death rate of TTG were higher than MG and UTG. Thus TSLC1 induced Eca109 cells to apoptosis. CONCLUSIONS: The TSLC1 gene had a potent effect on cell proliferation inhibition, G1/S cell cycle arrest and induction of cell apoptosis in Eca109 cells.

Function and histopathology of a cell adhesion molecule TSLC1 in cancer.

Even less than a decade since the discovery of TSLC1, overwhelming evidence demonstrates that the loss of TSLC1 expression by methylation-mediated epigenetic silencing or LOH is crucially implicated in various processes during tumorigenesis. Here, we summarize TSLC1 function, highlighting the concept that TSLC1 mediates the formation of tumor suppressor network via its multidomain structure and bridges extracellular adhesive activity with intracellular signaling. Next, we focus on the histopathology of TSLC1 in various cancers and the association with clinicopathological characteristics. On the basis of these, we propose that TSLC1 represents a promising biomarker for cancer diagnosis and a potential target for cancer therapy.

Construction of eukaryotic expression vector of TSLC1 gene.

INTRODUCTION: To construct a eukaryotic expression vector of the tumour suppressor in lung cancer 1 (TSLC1) gene, so as to explore the mechanisms of tumour suppression of the gene theoretically. MATERIAL AND METHODS: The open reading frame (ORF) of TSLC1 gene was amplified with RT-PCR from normal human foreskin acrobystia, and cloned to pMD19-T simple vector (TA Clone method). The resultant plasmid was transformed into Escherichia coli JM109 for amplification. The TA Clone recombinant was digested by double restriction enzyme (Bgl II/EcoR I) and analysed with agarose gel electrophoresis. The positive one was sequenced. The inserted DNA fragment was recovered, and then it was mounted into the eukaryotic expression vector pIRES2-EGFP, transformed into E. coli JM109 for amplification. A positive recombinant plasmid named pIRES2-EGFP-TSLC1 was confirmed by Bgl II/EcoR I double-enzyme digestion analysis. RESULTS: RT-PCR amplified the ORF of the TSLC1 gene. It was approximately 1400 base pairs. The obtained DNA was confirmed a high degree of homology with the sequence of TSLC1 cDNA sequence (AY358334) stored at GenBank. CONCLUSIONS: Construction of a TSLC1 eukaryotic expression vector was successful, and it has established a solid foundation for further study.

Prognostic value of serum soluble Fas in patients with locally advanced unresectable rectal cancer receiving concurrent chemoradiotherapy.

OBJECTIVE: This study was designed to detect the changes of serum soluble Fas (sFas) levels in patients with locally advanced unresectable rectal cancer (LAURC), and to explore its prognostic value of response. METHODS: Soluble samples were obtained from LAURC subjects, treated by concurrent chemoradiotherapy, before treatment and one month after treatment. Healthy donor serum samples were used as controls. sFas concentration was measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: The sFas levels before treatment and one month after treatment were both significantly higher in LAURC subjects than in healthy controls [(8.79±1.39) and (7.74±1.32) vs. (5.53±1.13) ng/L, P<0.01]. The sFas levels before treatment and one month after treatment were significantly lower in the response group (complete and partial responses) than in the non-response group (stable and progressive diseases) [(8.50±1.25) vs. (10.17±1.26) ng/L, P<0.01 and (7.50±1.24) vs. (8.90±1.13) ng/L, P<0.01, respectively]. The one-year survival rate was 54.2% and 82.6% in those with sFas levels >8.79 ng/L and <8.79 ng/L before treatment (P<0.02), respectively, 50.0% and 87.0% in those with sFas levels >7.74 ng/L and <7.74 ng/L one month after treatment (P<0.01), respectively. CONCLUSIONS: The sFas level is higher in LAURC subjects than in healthy controls. Concurrent chemoradiotherapy can reduce sFas levels in LAURC patients. The monitoring of sFas may provide prognostic information for LAURC patients.

Clinical significance of vascular endothelial growth factor and connexin43 for predicting pancreatic cancer clinicopathologic parameters.

Vasiformation is essential for the growth and metastasis of tumor. Vascular endothelial growth factor (VEGF) and connexin43 (Cx43) are important regulatory factors of vasiformation. This study aimed to find out the expression features of VEGF and Cx43 and their significance in pancreatic cancer. The expression levels of VEGF and Cx43 protein in the samples, which came from 100 patients of human pancreatic cancer tissues and adjacent normal pancreatic tissues, were examined by using immunohistochemical streptavidin-peroxidase (S-P) method, Western-blotting, and RT-PCR analyses. Compared with adjacent normal pancreatic tissues, RT-PCR showed that the expression of VEGF mRNA was significantly higher in pancreatic cancer tissues (0.788±0.290, P<0.01) and Cx43 mRNA was significantly lower in pancreatic cancer tissues (0.403±0.204, P<0.01). The expression of VEGF protein was higher in pancreatic cancer tissue (0.745±0.254, P<0.01) by Western-blot, and Cx43 protein was obviously lower in pancreatic cancer tissues (0.373±0.164, P<0.01). The immunohistochemical S-P method showed as follows: the positive expression rate of VEGF and Cx43 protein was 77 and 48% in pancreatic cancer tissues and 15 and 100% in adjacent normal pancreatic tissues; expressions of VEGF were related to tumor size, TNM stage, and lymph node metastasis (P<0.05); there was a close relation between the expression of Cx43 and histological grades, TNM stage, and lymph node metastasis (P<0.05). This present study suggests that VEGF is overexpressed and the expression of Cx43 is lower in pancreatic cancer. The expression of VEGF and Cx43 is significantly correlated with TNM stage and lymph node metastasis. Furthermore, VEGF and Cx43 may play an important role in the occurrence, development, and metastasis of pancreatic cancer. To examine VEGF and Cx43 may be of value in judging the malignancy degree and the prognosis of pancreatic cancer.

DcR3 and survivin are highly expressed in colorectal carcinoma and closely correlated to its clinicopathologic parameters.

OBJECTIVE: To investigate the expression of death decoy receptor 3 (DcR3) and survivin in colorectal carcinoma. METHODS: Tumor and normal tissues were taken from a total of 100 colorectal carcinoma patients during surgery, and the expression of DcR3 and survivin was examined by immunohistochemistry, Western blotting, and reverse transcription-polymerase chain reaction (RT-PCR) analyses. RESULTS: RT-PCR showed that the expression levels of DcR3 mRNA (0.846+/-0.242, P<0.01) and survivin mRNA (0.7835+/-0.2392, P<0.01) in colorectal cancer tissues were significantly higher than those in adjacent normal tissues. Western blotting showed that the expression levels of DcR3 protein (0.795+/-0.261, P<0.01) and survivin protein (0.6765+/-0.1351, P<0.01) in tumor tissues were significantly higher than those in non-cancer tissues. The immunohistochemical streptavidin-peroxidase (SP) method showed that the positive expression rates of DcR3 and survivin were 67.0% and 58.0% in colorectal cancer tissues, and 18.0% and 3.0% in non-cancerous colorectal tissues (P<0.05), respectively. The positive correlations of DcR3 (P<0.01) and survivin (P<0.01) to the differentiation of colorectal carcinoma cells, lymph node metastasis, and pathological stage were observed. The expression of DcR3 and survivin was found to be positively correlated to clinicopathologic parameters of colorectal carcinoma. CONCLUSION: The overexpressed DcR3 and survivin in colorectal cancer may contribute to the development of the cancer. The monitoring of these two proteins may be useful for the diagnosis, differentiation, metastasis, and determination of stages of colorectal carcinoma.