Establishment and characterization of an expanding-type gastric cancer cell line by Ming's classification

Establishment and characterization of a new human ampullary carcinoma cell line, DPC-X1

BACKGROUND

An in-depth study of the pathogenesis and biological characteristics of ampullary carcinoma is necessary to identify appropriate treatment strategies. To date, only eight ampullary cancer cell lines have been reported, and a mixed-type ampullary carcinoma cell line has not yet been reported.

AIM

To establish a stable mixed-type ampullary carcinoma cell line originating from Chinese.

METHODS

Fresh ampullary cancer tissue samples were used for primary culture and subculture. The cell line was evaluated by cell proliferation assays, clonal formation assays, karyotype analysis, short tandem repeat (STR) analysis and transmission electron microscopy. Drug resistances against oxaliplatin, paclitaxel, gemcitabine and 5-FU were evaluated by cell counting kit-8 assay. Subcutaneous injection 1 × 10⁶ cells to three BALB/c nude mice for xenograft studies. The hematoxylin-eosin staining was used to detect the pathological status of the cell line. The expression of biomarkers cytokeratin 7 (CK7), cytokeratin 20 (CK20), cytokeratin low molecular weight (CKL), Ki67 and carcinoembryonic antigen (CEA) were determined by immunocytochemistry assay.

RESULTS

DPC-X1 was continuously cultivated for over a year and stably passaged for more than 80 generations; its population doubling time was 48 h. STR analysis demonstrated that the characteristics of DPC-X1 were highly consistent with those of the patient’s primary tumor. Furthermore, karyotype analysis revealed its abnormal sub-tetraploid karyotype. DPC-X1 could efficiently form organoids in suspension culture. Under the transmission electron microscope, microvilli and pseudopods were observed on the cell surface, and desmosomes were visible between the cells. DPC-X1 cells inoculated into BALB/C nude mice quickly formed transplanted tumors, with a tumor formation rate of 100%. Their pathological characteristics were similar to those of the primary tumor. Moreover, DPC-X1 was sensitive to oxaliplatin and paclitaxel and resistant to gemcitabine and 5-FU. Immunohistochemistry showed that the DPC-X1 cells were strongly positive for CK7, CK20, and CKL; the Ki67 was 50%, and CEA was focally expressed.

CONCLUSION

Here, we have constructed a mixed-type ampullary carcinoma cell line that can be used as an effective model for studying the pathogenesis of ampullary carcinoma and drug development.

Establishment and characterization of a new gastric cancer cell line, XGC-1

Background

To establish a primary human gastric cancer cell line.

Methods

Fresh gastric cancer tissue samples were separated into a cell suspension, and DMEM/F12 medium containing 10% foetal bovine serum was used for primary culture and subculture. The morphology of the cells was observed under a light microscope, and the cell growth curve was plotted. A soft agar colony formation assay was used to detect the colony formation ability of the cell line. Immunohistochemical methods were used to detect cytokeratin, vimentin and Ki-67, the chromosome G banding method was used to analyse the karyotype of the cells, and the tumourigenic ability of the cells was detected by subcutaneous inoculation of BALB/C nude mice.

Results

We established a gastric cancer cell line from a 68-year-old male patient. This gastric cancer cell line was named XGC-1 and had a doubling time of approximately 48 h. The cell line displayed strong colony formation ability and tumourigenicity in BALB/C nude mice and had complicated chromosomal abnormalities. When nutrients were insufficient, the cells shed and floated in the medium, but adherent growth was observed in nutrient-rich conditions.

Conclusions

The XGC-1 cell line will be useful for future studies of gastric cancer development, progression, metastasis and therapy.

Identification of the Combinatorial Effect of miRNA Family Regulatory Network in Different Growth Patterns of GC

According to the growth pattern, gastric cancer (GC) could be classified into expanding-type GC and infiltrative-type GC (Ming’s classification). The growth pattern of GC is often related to the malignant degree, invasion, metastasis, and other pathological characteristics of tumors. MicroRNAs (miRNAs) play important roles in modulating gene expression during the GC development. In this study, miR-29s were significantly correlated with the gastric carcinogenesis and Ming’s classification. Biological function of miR-29s is most closely related to the pathway of extracellular matrix (ECM)-receptor interaction. ECM structural assembly, cell movement, and cell adhesion are the main functional categories of target genes in this pathway. Among these targets, the COL4A1 gene ranked at the top in the association analysis of combined miR-29s biological function and GC subtype, and miR-29s inhibited its translation by binding to the 3′ UTR region. Infiltrative-type GC cells secrete a higher level of COL4A1 protein than do expanding-type GC cells. The expression of COL4A1 in GC is correlated with clinicopathological features. Downregulation of COL4A1 expression significantly inhibited the migration and invasion of GC cells. High COL4A1 expression was correlated with poor prognosis in survival analysis. The miR-29s regulatory network may affect the development of growth patterns and pathological progress of GC by regulating the function of COL4A1.

Regulatory network of circRNA-miRNA-mRNA contributes to the histological classification and disease progression in gastric cancer

Background

Little has been known about the role of non-coding RNA regulatory network in the patterns of growth and invasiveness of gastric cancer (GC) development.

Methods

MicroRNAs (miRNAs) microarray was used to screen differential miRNA expression profiles in Ming’s classification. The significant differential expressions of representative miRNAs and their interacting circular RNA (circRNA) were confirmed in GC cell line and 63 pairs of GC samples. Then, a circRNA/miRNA network was constructed by bioinformatics approaches to identify molecular pathways. Finally, we explored the clinical value of the common targets in the pathway by using receiver operating characteristic curve and survival analysis.

Results

Significantly differential expressed miRNAs were found in two pathological types of GC. Both of miR-124 and miR-29b were consistently down-regulated in GC. CircHIPK3 could play a negative regulatory role on miR-124/miR-29b expression and associated with T stage and Ming’s classification in GC. The bioinformatics analyses showed that targets expression of circHIPK3-miR-124/miR-29b axes in cancer-related pathways was able to predict the status of GC and associated with individual survival time.

Conclusions

The targets of circHIPK3-miR-124/miR-29b axes involved in the progression of GC. CircHIPK3 could take part in the proliferation process of GC cell and may be potential biomarker in histological classification of GC.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1582-8) contains supplementary material, which is available to authorized users.