Purification and characterization a polysaccharide from Hedyotis diffusa and its apoptosis inducing activity toward human lung cancer cell line A549.

In this study, we first isolated and purified a homogeneous polysaccharide (HDP) from Hedyotis diffusa. Its molecular weight was estimated to be about 89 kDa and GC analysis identified that it was composed of glucose, galactose, and mannose in a molar ratio of 2.0:1.0:1.0. Treatment with HDP (25, 100, and 200 µg/ml) resulted in growth inhibitory effect on A549 cells by inducing apoptosis. Moreover, induction of apoptosis by HDP was accompanied with the release of cytochrome c from mitochondria into the cytosol prior to the activation of caspase-9 and -3 in A549 cells. Also, a higher ratio of Bax/Bcl-2 proteins was observed in A549 cells followed by HDP treatment. Additionally, in vivo study showed that HDP (50 and 100 mg/kg) could suppress the growth of A549 subcutaneous xenograft tumors. Taken together, these results indicated that the HDP exerted an anticancer effect in vitro and in vivo and may be useful as a potent antitumor agent for the prevention of lung cancer.

A polysaccharide from Hedyotis diffusa interrupts metastatic potential of lung adenocarcinoma A549 cells by inhibiting EMT via EGFR/Akt/ERK signaling pathways.

In this study we investigated the potential effects of a polysaccharide (HDP) from Hedyotis diffusa on the metastasis in human lung adenocarcinoma A549 cells. HDP (25, 50 and 100µg/ml) significantly suppressed the cell adhesion, invasion and migration of A549 cells in a dose dependent manner by downregulation of matrix metalloproteinase (MMP-2 and MMP-9) and upregulation of tissue inhibitors of metalloproteinase (TIMP-2 and TIMP-9). Moreover, HDP effectively downregulated the protein expressions of epithelial-mesenchymal transition (EMT) markers (N-cadherin and vimentin), and upregulated E-cadherin protein expression, which is involved in interrupting EGFR/Akt/ERK signaling pathways, as well as inhibiting COX-2 protein expression. All these results demonstrated that HDP might be a novel anti-metastatic agent for NSCLC treatment.

Correlation between the presence of circulating tumor cells and the pathologic type and staging of non-small cell lung cancer during the early postoperative period.

This study investigated possible correlations between the presence of circulating tumor cells (CTCs) and the pathologic types and staging of non-small cell lung cancer (NSCLC) during the early postoperative period. Sixty-nine patients with NSCLC were enrolled in the study. Clinical staging was performed by postoperative pathological examination and imaging. Multiple mRNA in situ analyses targeting specifically expressed genes were carried out to identify the presence of CTCs. Correlations between age, sex, TNM stage and pathological types with the detection rate of CTCs were also established. The results showed the positivity rate of CTCs in patients >55 years was significantly higher than that of patients <55 years (94.74 vs. 70.97%, P<0.05). There was no significant difference in the positivity rate of CTCs between male and female patients (85.71 vs. 85.29%, P>0.05). The correlations between the detection rate of epithelial type or mixed type CTCs with tumor size, lymph node metastasis and distant metastasis TNM in patients with NSCLC were not significant (P>0.05). However, higher TNM stages correlated with higher detection rates of mesenchymal CTCs (P<0.05). There were also significant differences in the detection rates of CTCs amongst the three different pathologic types (adenocarcinoma, squamous cell and large cell carcinomas) (P<0.05). Based on our results, the detection of mesenchymal CTCs during the early postoperative period can help prognosticate the recurrence and metastasis of NSCLC, which is beneficial to the development of individualized treatment strategies.

Overexpression of miR-191 Predicts Poor Prognosis and Promotes Proliferation and Invasion in Esophageal Squamous Cell Carcinoma.

PURPOSE: Accumulating evidence has shown that dysregulation of microRNA-191 (miR-191) is closely associated with tumorigenesis and progression in a wide range of cancers. This study aimed to explore the potential role of miR-191 in esophageal squamous cell carcinoma (ESCC). MATERIALS AND METHODS: miR-191 expression was assessed in 93 ESCC tissue specimens by real-time polymerase chain reaction, and survival analysis was performed via Kaplan-Meier and Cox regression analyses. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, plate colony-forming, BrdU, and Transwell assays were conducted to observe the effect of miR-191 on ESCC proliferation and invasion. Luciferase reporter and western blot assays were taken to identify target genes of miR-191. RESULTS: miR-191 was overexpressed in 93 cases of ESCC, compared with adjacent normal tissues, and miR-191 expression was significantly related to differentiation, depth of invasion, TNM stage, lymph node metastasis, and distant metastasis of tumor. Kaplan-Meier and Cox regression analyses demonstrated that overexpression of miR-191 was an independent and significant predictor of ESCC prognosis. Both gain-of-function and loss-of-function experiments showed that miR-191 promoted ESCC cell proliferation and invasion activities in vitro. Early growth response 1 (EGR1), a tumor suppressor, was predicted as a direct target of miR-191. Luciferase reporter and western blot assays proved that miR-191 reduced EGR1 expression by directly binding its 3' untranslated region. Moreover, EGR1 knockdown by siRNA enhanced ESCC cell growth and invasion. CONCLUSION: Our findings provide specific biological roles of miR-191 in ESCC survival and progression. Targeting the novel miR-191/EGR1 axis represents a potential new therapeutic way to block ESCC development.

High expression of miR-493-5p positively correlates with clinical prognosis of non small cell lung cancer by targeting oncogene ITGB1.

Increasing evidence supports that microRNA (miRNA)-mediated gene regulation plays a significant functional role in cancer progression. To investigate the expression and clinical significance of ITGB1 in non small cell lung cancer (NSCLC), the expression levels of ITGB1 in NSCLC tissues and human normal lung tissues were analyzed in silico using genes microarray, KEGG pathway and hierarchical clustering analysis followed by validation with quantitative RT-PCR. Our results showed that ITGB1 was upregulated in NSCLC tissues when compared with normal lung tissues. Survival analysis based on the qRT-PCR data established that ITGB1 expression was attentively related to the prognosis of NSCLC, and patients with higher ITGB1 expression had shorter overall survival (OS). Moreover, ITGB1 was confirmed to be a direct target of miR-493-5p. Furthermore, concomitant high expression of ITGB1 and low expression of miR-493-5p correlated with a shorter median OS and PFS in NSCLC patients. In conclusion, our results provide the first evidence that ITGB1 is a direct target of miR-493-5p suggesting that ITGB1 and miR-493-5p may have potential prognostic value and may be useful as tumor biomarkers for the diagnosis of NSCLC patients.