Characteristics of a novel cell line ZJU-0430 established from human gallbladder carcinoma

CD24 and tumor budding as a prognostic variable in carcinoma gall bladder: A pilot study

BACKGROUND

CD24 is a small heavily glycosylated glycosylphosphotidylinositol-linked cell surface protein that is expressed in a variety of hematological and solid tumors. It is majorly involved in tumor development, proliferation, invasion, metastasis, and prevention of tumor cell death via various major and minor signalling pathways although it can also inhibit invasiveness via degrading BART mRNA.

AIM AND OBJECTIVE

We aimed to evaluate CD24 expression in gall bladder carcinoma (GBC), via immunohistochemical (IHC) staining on paraffin-embedded histological tissue along with assessment of tumor budding.

MATERIAL AND METHODS

87 patients were enrolled and CD24 IHC staining was evaluated using four degrees of positivity (negative, mild, moderate, and strong). The expression was then correlated with various clinicopathological parameters. Interpretation was tumor budding was done on the H and E slide. Hotspots were chosen and the total number of buds was reported in an area measuring 0.785 mm2 corresponding to 20× fields in the microscope.

RESULTS

CD24 positive expression was found in 77.5% of cases. Its positive expression correlated inversely with tumor stage, necrosis, and lymph vascular invasion establishing its usefulness as a prognostic marker. Tumor budding correlated with poor tumor differentiation and higher tumor grade and poorly differentiated cancer with higher budding responded well to chemotherapy.

CONCLUSION

Our study supports the importance of CD24 and tumor budding as prognostic markers and thus its usefulness in risk stratification in GBC. CD 24 positive subgroup of GBC cases may benefit from anti-CD24 mAb therapy and we also recommend that tumor budding may be included in the morphological synoptic reporting in gall bladder cancer.

Dynamic gene expression pattern in zebrafish gallbladder: an experimental study

Gallbladder cancer (GBC) is one of the common biliary tract malignancies that is often associated with late presentation of clinical symptoms resulting in poor prognosis, thereby considerably increasing the mortality rate. Geographic and ethnic variations are one of the major causes of GBC incidence. However, in addition to genetic susceptibility to GBC, other factors like age, obesity, sex, and exposure to certain heavy chemicals may also lead to the incidence of GBC. Most of GBC research has so far used traditional cell culture systems. Recently, newer approaches using 2D and 3D cultures, xenograft models, and organoids are also becoming popular. However, whole organism model systems for GBC research have not yet been established. In this study, the authors propose the use of zebrafish as a model organism to study GBC. However, the zebrafish gallbladder is relatively unexplored besides the anatomical features. Here, the authors unravel and then compare the unique transcriptomic profile of zebrafish gallbladder with humans to identify genes consistently expressed in both species. The authors provide a comprehensive list of all gallbladder specific genes in zebrafish that also have their orthologous counterparts in humans. Therefore, they can be used as potential biomarkers for gallbladder transcriptomic profile. To the best of our knowledge, this is the only study so far to provide a complete genomic expression profile of zebrafish gallbladder along with an exhaustive cross-species comparison, thus paving the path for using zebrafish as a model organism to study GBC and help identify novel biomarkers for its early detection and diagnosis.

FAM84B promotes breast cancer tumorigenesis through activation of the NF-κB and death receptor signaling pathways

Breast cancer (BC) occurs predominantly in women and leads to numerous deaths every year. The identification of effective therapeutic targets will benefit BC patients and increase the likelihood of finding a cure. Family with similar sequence 84, member B (FAM84B) has been implicated in the progression of many kinds of cancers, but its function in BC remains to be explored. In this study, online database analysis revealed that FAM84B expression was higher in BC patient tissues, especially in luminal BC tissues, than in the corresponding normal tissues; furthermore, increased FAM84B expression was related to poor prognosis. Additionally, western blot (WB) analysis revealed that the FAM84B protein was highly expressed in luminal BC cell lines compared to normal and basal-like BC cell lines. Moreover, clinical BC patient tissues were collected and subjected to WB and immunohistochemical (IHC) analyses, and the results showed that FAM84B was expressed mainly in luminal BC samples. Therefore, to determine the function of FAM84B in luminal BC cells, luminal BC cell lines with FAM84B knockout and overexpression were generated. In addition, the functions of FAM84B were evaluated in vitro (via cell proliferation, wound healing, colony formation and invasion assays) and in vivo (via a subcutaneous xenograft experiment), and the results showed that FAM84B regulated cell proliferation but not cell invasion. Furthermore, the results of RNA sequencing analysis in ZR-75-1 FAM84B knockout and FAM84B-overexpressing cells showed that FAM84B could affect the TNF signaling pathway. Subsequently, WB analysis of death receptor signaling and immunofluorescence (IF) analysis of NF-κB p65 localization revealed that FAM84B affected death receptor signaling and promoted NF-κB p65 nuclear entry. In conclusion, we found that FAM84B promotes luminal BC tumorigenesis through the activation of the NF-κB and death receptor signaling pathways.

Establishment and characterization of an immortalized epithelial cell line from human gallbladder

Background

Although a plethora of studies have employed multiple gallbladder cancer (GBC) cell lines, it is surprisingly noted that there is still lack of a normal gallbladder epithelial cell line as a normal counterpart, thus impeding substantially the progress of mechanistic studies on the transformation of normal epithelial cells to cancer. Here, we created a normal gallbladder epithelial cell line named L-2F7 from human gallbladder tissue.

Methods

Gallbladder tissues from a diagnosed cholecystitis female patient were collected, and epithelial cells were enriched by magnetic cell sorting. Then, the cells were immortalized by co-introduction of human telomerase reverse transcriptase (hTERT) and Simian virus 40 large T antigen (LT-SV40) via a lentivirus infection system. After clonal selection and isolation, L-2F7 cells were tested for epithelial markers CK7, CK19, CK20, and CD326, genomic feature, cell proliferation, and migration using Western blot, immunofluorescence, whole genome sequencing, karyotyping, and RNA sequencing. L-2F7 cells were also transplanted to Nude (nu/nu) mice to determine tumorigenicity.

Results

We successfully identified one single-cell clone named L-2F7 which highly expressed epithelial markers CD326, CK7, CK19, and CK20. This cell line proliferated with a doubling time of 23 h and the epithelial morphology sustained over 30 passages following immortalization. Transient gene transduction of L-2F7 cells led to expression of exogenous GFP and FLAG protein. L-2F7 cells exhibited both distinct non-synonymous mutations from those of gallbladder cancer tissues and differential non-cancerous gene expression patterns similar to normal tissue. Although they displayed unexpected mobility, L-2F7 cells still lacked the ability to develop tumors.

Conclusion

We developed a non-cancerous gallbladder epithelial cell line, offering a valuable system for the study of gallbladder cancer and other gallbladder-related disorders.

HMGA2 promotes the migration and invasion of gallbladder cancer cells and HMGA2 knockdown inhibits angiogenesis via targeting VEGFA

The high mobility group AT-hook 2 (HMGA2) protein has been found to be upregulated in the majority of tumor types and is associated with a poor prognosis. Previous studies have suggested the oncogenic role of HMGA2 in gallbladder cancer (GBC). The present study aimed to investigate the effects of HMGA2 on the invasion, migration and angiogenesis of GBC cells. To achieve this aim, HMGA2 was overexpressed or silenced in the GBC cell line, EH-GB1, and then the proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) abilities of EH-GB1 cells were investigated using Cell Counting Kit-8, wound healing, Transwell and western blotting assays. In addition, the expression levels of VEGFA were determined in EH-GB1 cells using western blotting and reverse transcription-quantitative PCR following HMGA2 overexpression or silencing. Furthermore, HMGA2-silenced EH-GB1 cells were transfected with VEGFA overexpression plasmids to evaluate the tube formation ability of HUVECs using tube formation assay. The results demonstrated that HMGA2 silencing inhibited GBC cell proliferation, migration, invasion and EMT, as evidenced by the downregulated expression of Ki67, proliferating cell nuclear antigen, MMP2, MMP9, N-cadherin, snail family transcriptional repressor 2 and zinc finger E-box-binding homeobox 1, and attenuated cell migration and invasion. However, the opposite results were obtained following HMGA2 overexpression. Moreover, HMGA2 knockdown and overexpression downregulated and upregulated VEGFA expression, respectively. In addition, the tube formation ability of HUVECs and the expression levels of CD31, VEGFR1 and VEGFR2 were downregulated following HMGA2 silencing. However, these effects were partially rescued by simultaneous VEGFA overexpression. In conclusion, the findings of the present study revealed that HMGA2 may promote GBC cell migration, invasion, EMT and angiogenesis. Therefore, inhibiting HMGA2 expression could be considered as a possible therapeutic approach for GBC.

Salmonella enterica subsp. enterica host-pathogen interactions and their implications in gallbladder cancer

BACKGROUND

Several studies have linked chronic typhoid infection with gallbladder carcinoma without completely understood mechanism. This study was performed in order to understand role of Salmonella in gallbladder cancer etiology.

METHODS

Known Salmonella host-pathogen interactions were screened from database in addition to known gallbladder carcinoma targets. Host-pathogen interaction map of S. enterica was prepared and screened for interactions with gallbladder carcinoma targets. Further functional overrepresentation analysis was performed to understand the role of human targets involved in Salmonella host-pathogen interactions in gallbladder carcinoma.

RESULTS

Salmonella interact with several human proteins involved in gallbladder carcinoma. MAPK and RAC1 are the most important human proteins based on node degree value among all GBC associated interactors identified in current data search. Functional over-representation analysis reveals that Salmonella can induce adenocarcinoma which constitutes 85% of gallbladder cancer.

CONCLUSION

Though, the role of MAPK/ERK and PI3K/AKT/mTOR pathway is already suggested for Salmonella mediated gallbladder cancer, but current data based approach indicate several new insight for exploration of the role of Salmonella in gallbladder cancer etiology. The results indicate about several other processes including CREB/SP-1 and BSG(CD147) signaling, that must be given consideration for understanding the role of Salmonella in gallbladder cancer.

Establishment and characterization of 38 novel patient-derived primary cancer cell lines using multi-region sampling revealing intra-tumor heterogeneity of gallbladder carcinoma

Gallbladder carcinoma (GBC) is a lethal biliary tract malignant neoplasm. Patient-derived primary cancer cell lines (PDPCs) are appropriate models to explore biological characteristics and potential therapeutics; however, there is a lack of PDPCs in GBC. In this study, we aimed to establish and characterize the GBC PDPCs, and further investigated the intra-tumor heterogeneity (ITH). Multi-region sampling (3–9 regions) of the operable tumor tissue samples was used to establish PDPCs. Short tandem repeat genotyping for cell authentication and karyotyping was performed, followed by whole-exome sequencing and RNA sequencing to assess the ITH at the genetic and transcriptional levels, respectively. Thirty-eight PDPCs were successfully established from seven GBC patients and characterized. ITH was observed with a median of 38.3% mutations being heterogeneous (range, 26.6–59.4%) across all patients. Similar with other tumor types, TP53 mutations were always truncal. In addition, there were three genes, KMT2C, CDKN2A, and ARID1A, with truncal mutations in at least two patients. A median of 370 differentially expressed genes (DEGs) was identified per patient. Distinct expression patterns were observed between major histocompatibility complex (MHC) class I and II genes. We found the expression of MHC class II genes in the PDPC samples was closely regulated by CIITA, while that of MHC class I genes were not correlated with CIITA expression. The PDPCs established from GBC patients can serve as novel in vitro models to identify the ITH, which may pave a crucial molecular foundation for enhanced understanding of tumorigenesis and progression.