Increasing evidences indicate that shikonin can suppress the tumor growth. However, the mechanisms remain elusive. In the present study, we investigated the effects and mechanisms of shikonin against esophageal cancer. The expression of hypoxia inducible factor 1α (HIF1α) and pyruvate kinase M2 (PKM2) in esophageal cancer tissues and cells was detected by immunohistochemistry and Western blot. CCK-8 was used to examine the esophageal cancer cell viability. Apoptosis and cell cycle were analyzed by flow cytometry. The expression of EGFR, PI3K, Akt, p-AKT, mTOR, HIF1α and PKM2 was detected by Western blot. EC109/pkm2 was established by lentivirus transducer. Ec109 tumor model was founded to observe the antitumor effect of shikonin in vivo.

The purpose of this study was to observe the effects of metformin on human esophageal cancer cell and to investigate its possible mechanisms. Cell viability was detected by using a Cell Counting Kit-8, while cell cycle and apoptosis were assessed by flow cytometry and western blot was used to measure the expression of the related proteins. RNAi was used to knockout pyruvate kinase muscle isozyme 2 (PKM2). An Eca109 tumor model was established to evaluate the antitumor effect in vivo. Immunohistochemistry was determined based on the expression of PKM2 and Bim in tumor tissues. Tunnel was used to assess tumor cell apoptosis. Esophageal cancer cells viability was reduced after metformin treatment. The cell cycle was arrested in the G0/G1 phase, apoptosis was induced, caspase 3 was activated, caspase 9 was downregulated, and the pro-apoptotic protein Bim increased. Further study revealed that metformin could suppress the expression of insulin-like growth factor 1 receptor and its downstream proteins, phosphoinositide 3-kinase (PI3K), protein kinase B (AKT/PKB), phosphorylation of AKT (pAKT), mammalian target of rapamycin (mTOR), p70S6K, and PKM2. Insulin-like growth factor 1 partly reversed metfromin-induced apoptosis and attenuated the repression effect of metfomin to PI3K, pAKT, and PKM2. Knockout PKM2 resulted in the activation of caspase 3, down-regulation of caspase 9, and increased expression of Bim. In the Eca109 xenograft model, metformin significantly reduced tumor growth. Furthermore, we found that metformin treatment increased the rate of apoptosis, down-regulation of PKM2, and up-regulation of Bim in tumor tissues. Metformin restrained esophageal cancer cell proliferation partly by suppressing the PI3K/AKT/mTOR pathway.

Non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR)-sensitive mutations benefit from epidermal growth factor receptor tyrosine kinase inhibitors (EGFR- TKIs). However, drug resistance is a major cause of therapeutic failure. This study examined whether saikosaponin-d (SSD) enhances the anti-tumor effect of gefitinib in NSCLC cells. Cell Counting Kit-8 (CCK-8) was used to determine cell viability. Cell apoptosis was examined by flow cytometry. Signal transducer and activator of transcription (STAT3), phosphor-STAT3 (P-STAT3), and B-cell lymphoma 2 (Bcl-2) were detected by Western blot. An HCC827/GR tumor model was established to observe the effect of combination therapy in vivo. The combination of SSD with gefitinib had an enhanced inhibitory effect by reducing cell viability and inducing cells apoptosis in NSCLC cells. Furthermore, SSD decreased and increased the expression of P-STAT3 and Bcl-2, respectively. Down-regulated STAT3 promoted the sensitivity of lung cancer cells to gefitinib. The results of animal experiments also showed that SSD enhanced the anti-tumor effect of gefitinib. These results indicated that the combination of SSD with gefitinib had an increased antitumor effect in NSCLC cells and that the molecular mechanisms were associated with the inhibition of STAT3/Bcl-2 signaling pathway. Our findings suggest a promising approach for the treatment of NSCLC patients with EGFR-TKI resistance.

Background: Esophageal squamous cell carcinoma (ESCC) is a common digestive tract malignant tumor with high incidence and dismal prognosis worldwide. However, the reliable biomarkers for clinical diagnosis and the underlying signaling pathways insights of ESCC are not unequivocally understood yet. The serum proteome may provide valuable clues for the early diagnosis of ESCC and the discovery of novel molecular insights. Methods: In the current study, an optimized proteomics approach was employed to discover novel serum-based biomarkers for ESCC, and unveil abnormal signal pathways. Gene ontology (GO) enrichment analysis was done by Gene Set Enrichment Analysis (GSEA) and Metascape database, respectively. Pathway analysis was accomplished by GeneCards database. The correlation coefficient was assessed using Pearson and distance correlation analyses. Prioritized candidates were further verified in two independent validation sets by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) staining. Results: A total of 633 non-redundant proteins were identified in the serum of patients with ESCC, of which 59 and 10 proteins displayed a more than 1.5-fold increase or decrease compared with healthy controls. Verification was performed for six candidate biomarkers, including S100A8/A9, SAA1, ENO1, TPI1 and PGAM1. Receiver operating characteristics (ROC) curve plotting showed the high diagnostic sensitivity and specificity of these six protein molecules as a biomarker panel: the area under characteristic curve (AUC) is up to 0.945. Differentially expressed proteins were subjected to functional enrichment analysis, which revealed the dysregulation of signaling pathways mainly involved in glycolysis, TLR4, HIF-1α, Cori cycle, TCA cycle, folate metabolism, and platelet degranulation. The latter finding was all the more noteworthy as a strong positive correlation was discovered between activated glycolysis and TLR4 pathways and unfavorable clinicopathological TNM stages in ESCC. Conclusions: Our findings propose a potential serum biomarker panel for the early detection and diagnosis of ESCC, which could potentially broaden insights into the characteristics of ESCC from the proteomic perspective.