Stromal interaction molecule 1 promotes tumor growth in Esophageal squamous cell carcinoma

3,3'-Diindolylmethane inhibits the proliferation of esophageal squamous cell carcinoma cells via downregulation of STIM1

3,3'-Diindolylmethane (DIM) is a natural phytochemical derived from cruciferous plants that has inhibitory effects on a wide range of tumor cells; however, its relevant effects on esophageal cancer cells have been poorly studied. Therefore, in the present study, a pharmacology network approach was used to predict the possible core targets of DIM acting on esophageal cancer. Subsequently, using in vitro experiments, TE-1 human esophageal cancer cells were treated with different concentrations of DIM (0, 40, 60 and 80 µM) for 24 h. Changes in cell activity were detected by Cell Counting Kit-8 assay, and changes in the expression levels of stromal interaction molecule 1 (STIM1) and apoptosis-related proteins, B-cell lymphoma-2 (Bcl-2) and Bax, were assessed by western blotting, followed by the upregulation of STIM1 by thapsigargin (Tg). Network pharmacology analysis showed that there were 39 potential core targets of DIM in esophageal cancer. The results of the in vitro experiments showed that DIM could inhibit the viability of esophageal cancer cells, downregulate the expression of STIM1 and Bcl-2 proteins and upregulate the expression of Bax protein, all in a concentration-dependent manner. The results also demonstrated that toxic carotenoids were agonist against STIM1 protein and upregulated STIM1 and Bax protein expression. After agonizing STIM1 protein expression using Tg, DIM was able to counteract the expression trend of STIM1, Bcl-2 and Bax protein in TE-1 cells. In summary, DIM induced apoptosis and inhibited the viability of esophageal cancer cells by downregulating the expression of STIM1 protein; therefore, the natural phytochemical, DIM, may be a potential substance for the early prevention and treatment of esophageal cancer cells.

STIM1/SOX2 proteins are co-expressed in the tumor and microenvironmental stromal cells of pancreatic ductal adenocarcinoma and ampullary carcinoma

Pancreatic ductal adenocarcinoma (PDAC) and ampullary carcinoma (AAC) are lethal malignancies with modest benefits from surgery. SOX2 and STIM1 have been linked to anticancer activity in several human malignancies. This study included 94 tumor cases: 48 primary PDAC, 25 metastatic PDAC, and 21 primary AAC with corresponding non-tumor tissue. All cases were immunohistochemically stained for STIM1 and SOX2 and results were correlated with clinicopathologic data, patient survival, and BCL2 immunostaining results. Results revealed that STIM1 and SOX2 epithelial/stromal expressions were significantly higher in PDAC and AAC in comparison to the control groups. STIM1 and SOX2 expressions were positively correlated in the primary and metastatic PDAC (P = 0.016 and, P = 0.001, respectively). However, their expressions were not significantly associated with BCL2 expression. SOX2 epithelial/stromal expressions were positively correlated with the large tumor size in the primary AAC group (P = 0.052, P = 0.044, respectively). STIM1 stromal and SOX2 epithelial over-expressions had a bad prognostic impact on the overall survival of AAC (P = 0.002 and P = 0.001, respectively). Therefore, STIM1 and SOX2 co-expression in tumor cells and intra-tumoral stroma could contribute to the development of PDAC and AAC. STIM1/SOX2 expression is linked to a bad prognosis in AAC.

TJP1, a Membrane-Expressed Protein, is a Potential Therapeutic and Prognostic Target for Lung Cancer

Objective: Lung cancer is a malignant tumor with the highest mortality rate in the world. It is necessary to develop effective biomarkers for diagnosis or prognostic treatment to improve the survival rate of patients. In this prospective study, we identified a membrane-expressed protein Tight Junction Protein 1 (TJP1), which is an ideal therapeutic target for lung cancer, and demonstrated its role in invasion, migration, and proliferation of lung cancer. Methods: High-throughput monoclonal antibody microarrays were used to screen for differential expression of monoclonal antibodies (mAbs) in lung cancer and normal lung tissue. Differentially expressed antibodies were used to immunoprecipitate their cellular targets to be identified by mass spectrometry. The identified target TJP1 was knocked down to observe the effect of reduced gene expression on lung cancer cell function. Immunohistochemistry on human tumor tissues and The Cancer Genome Atlas (TCGA) database was used to explore the relationship between TJP1 expression in multiple cancer types and patient prognosis. Results: The antibody CL007473 was overexpressed in tumor tissue and its target protein was identified by mass spectrometry and immunofluorescence as TJP1, a membrane-expressed protein. Knockdown of TJP1 in lung cancer cell lines showed that reduced expression of TJP1 could inhibit the invasion and migration of lung cancer cells and inhibit the proliferation of cancer cells, suggesting that membrane-expressed protein TJP1 may be used as a therapeutic target for lung cancer. TCGA database analysis showed that TJP1 was highly expressed in pancreatic cancer (PAAD) tissues compared with normal tissues, and low expression was more beneficial to the prognosis and survival of PAAD patients. Conclusion: Membrane-expressed protein TJP1 may be a good therapeutic and prognostic target for lung cancer and has the potential to be a prognostic biomarker in pancreatic cancer.

Silencing Sirtuin 6 induces cell cycle arrest and apoptosis in non-small cell lung cancer cell lines

Sirtuins (SIRT1-7), are NAD-dependent deacetylases and ADP-ribosyl transferases, plays a major part in carcinogenesis. The previous report suggests that in cancer, sirtuins gained tremendous interest and critical regulators of the unusual processes. In carcinogenesis, sirtuins possess either tumor suppressor or promoter. However, in lung cancer condition the studies of sirtuins are less studied. Hence, this designed study investigates the impact of multifaceted sirtuins in NSCLC cells. We evaluated the mRNA and protein expressions of sirtuins by RTPCR and western blot. We found SIRT6 significantly overexpressed in NCI-H520, A549, and NCI-H460 compared with the normal BEAS-2B cell line. Silencing of SIRT6 by siRNA in NSCLC cells caused activation of p53/p21 mediated inhibition of cell proliferation leading to arrest in cell cycle and apoptosis induction. Our results implied that SIRT6 is a tumor promoter in NSCLC development, progression, and regulation. The silencing of SIRT6 to be a novel therapy for lung cancer.