Ying Tian

Circulating miR‐221 directly amplified from plasma is a potential diagnostic and prognostic marker of colorectal cancer and is correlated with p53 expression

Background and Aim:  Circulating miRNAs exist in serum and plasma and they can be used as a potential noninvasive molecular marker for colorectal cancer (CRC) diagnosis. The present study was to test the availability of direct amplification of miRNAs from plasma without RNA extraction, and to evaluate its clinical application value in CRC.

Activation of notch-1 enhances epithelial-mesenchymal transition in gefitinib-acquired resistant lung cancer cells

Despite an initial response to EGFR tyrosine kinase inhibitors (EGFR‐TKI) in EGFR mutant lung cancer, most patients eventually become resistant and result in treatment failure. Recent studies have shown that epithelial to mesenchymal transition (EMT) is associated with drug resistance and cancer cell metastasis. Strong multiple gene signature data indicate that EMT acts as a determinant of insensitivity to EGFR‐TKI. However, the exact mechanism for the acquisition of the EMT phenotype in EGFR‐TKI resistant lung cancer cells remains unclear. In the present study, we showed that the expression of Notch‐1 was highly upregulated in gefitinib‐resistant PC9/AB2 lung cancer cells. Notch‐1 receptor intracellular domain (N1IC), the activated form of the Notch‐1 receptor, promoted the EMT phenotype in PC9 cells. Silencing of Notch‐1 using siRNA reversed the EMT phenotype and restored sensitivity to gefitinib in PC9/AB2 cells. Moreover, Notch‐1 reduction was also involved in inhibition of anoikis as well as colony‐formation activity of PC9/AB2 cells. Taken together, these results provide strong molecular evidence that gefitinib‐acquired resistance in lung cancer cells undergoing EMT occurs through activation of Notch‐1 signaling. Thus, inhibition of Notch‐1 can be a novel strategy for the reversal of the EMT phenotype thereby potentially increasing therapeutic drug sensitivity to lung cancer cells. J. Cell. Biochem. 113: 1501–1513, 2012.

Network meta-analysis of erlotinib, gefitinib, afatinib and icotinib in patients with advanced non-small-cell lung cancer harboring EGFR mutations.

Background Several EGFR-tyrosine kinase inhibitors (EGFR-TKIs) including erlotinib, gefitinib, afatinib and icotinib are currently available as treatment for patients with advanced non-small-cell lung cancer (NSCLC) who harbor EGFR mutations. However, no head to head trials between these TKIs in mutated populations have been reported, which provides room for indirect and integrated comparisons. Methods We searched electronic databases for eligible literatures. Pooled data on objective response rate (ORR), progression free survival (PFS), overall survival (OS) were calculated. Appropriate networks for different outcomes were established to incorporate all evidences. Multiple-treatments comparisons (MTCs) based on Bayesian network integrated the efficacy and specific toxicities of all included treatments. Results Twelve phase III RCTs that investigated EGFR-TKIs involving 1821 participants with EGFR mutation were included. For mutant patients, the weighted pooled ORR and 1-year PFS of EGFR-TKIs were significant superior to that of standard chemotherapy (ORR: 66.6% vs. 30.9%, OR 5.46, 95%CI 3.59 to 8.30, P<0.00001; 1-year PFS: 42.9% vs. 9.7%, OR 7.83, 95%CI 4.50 to 13.61; P<0.00001) through direct meta-analysis. In the network meta-analyses, no statistically significant differences in efficacy were found between these four TKIs with respect to all outcome measures. Trend analyses of rank probabilities revealed that the cumulative probabilities of being the most efficacious treatments were (ORR, 1-year PFS, 1-year OS, 2-year OS): erlotinib (51%, 38%, 14%, 19%), gefitinib (1%, 6%, 5%, 16%), afatinib (29%, 27%, 30%, 27%) and icotinib (19%, 29%, NA, NA), respectively. However, afatinib and erlotinib showed significant severer rash and diarrhea compared with gefitinib and icotinib. Conclusions The current study indicated that erlotinib, gefitinib, afatinib and icotinib shared equivalent efficacy but presented different efficacy-toxicity pattern for EGFR-mutated patients. Erlotinib and afatinib revealed potentially better efficacy but significant higher toxicities compared with gefitinib and icotinib.

Effects of an oral allosteric AKT inhibitor (MK-2206) on human nasopharyngeal cancer in vitro and in vivo

Aim Protein kinase B (AKT) signaling frequently is deregulated in human cancers and plays an important role in nasopharyngeal carcinoma (NPC). This preclinical study investigated the effect of MK-2206, a potent allosteric AKT inhibitor, on human NPC cells in vitro and in vivo. Methods The effect of MK-2206 on the growth and proliferation of CNE-1, CNE-2, HONE-1, and SUNE-1 cells was assessed by Cell Counting Kit 8 and colony formation assay. Flow cytometry was performed to analyze cell cycle and apoptosis. The effects of MK-2206 on the AKT pathway were analyzed by Western blotting. Autophagy induction was evaluated via electron microscopy and Western blot. To test the effects of MK-2206 in vivo, CNE-2 cells were subcutaneously implanted into nude mice. Tumor-bearing mice were treated orally with MK-2206 or placebo. Tumors were harvested for immunohistochemical analysis. Results In vitro, MK-2206 inhibited the four NPC cell line growths and reduced the sizes of the colonies in a dose-dependent manner. At 72 and 96 hours, the half maximal inhibitory concentration (IC50) values of MK-2206 in CNE-1, CNE-2, and HONE-1 cell lines were 3–5 μM, whereas in SUNE-1, IC50 was less than 1 μM, and MK-2206 induced cell cycle arrest at the G1 phase. However, our study found no evidence of apoptosis. MK-2206 induced autophagy in NPC cells, as evidenced by electron microscopy and Western blot, and inhibited the growth of tumors that were subcutaneously implanted in mice. Inhibition of downstream phosphorylation through the PRAS40 and S6 pathways seems to be the main mechanism for the MK-2206-induced growth inhibition. Conclusion Our preclinical study suggests that MK-2206’s antiproliferative effect may be useful for NPC treatment; however, strategies for reinforcing this effect are needed to maximize clinical benefit.

PD-L1 is remarkably over-expressed in EBV-associated pulmonary lymphoepithelioma-like carcinoma and related to poor disease-free survival

Backgroud Programmed cell death-ligand 1 (PD-L1) and driver mutations are commonly seen in non-small-cell lung cancer (NSCLC). However, the prevelance of PD-L1 over-expression and its prognostic value in Epstein–Barr virus (EBV) associated pulmonary lymphoepithelioma-like carcinoma (LELC) remains poorly understood. Methods A total of 214 NSCLC patients and 113 surgically treated pulmonary LELC patients were included. Paraffin-embedded tumor sections were stained with PD-L1 antibody. Correlations between PD-L1 expression and clinicopathological features as well as survival outcomes were analyzed. Results The frequency of PD-L1 over-expression in NSCLC was 51.4%. No significant association was observed between common driver mutations and PD-L1 over-expression. Remakably, the positive rate of PD-L1 in pulmonary LELC was 74.3%. High PD-L1 expression was associated with impaired diseas-free survival (DFS) compared with low PD-L1 expression (p = 0.008). Multivariate analysis shows that PD-L1 expression level, N stage and M stage were independent prognostic factors for DFS. N stage and M stage but not PD-L1 expression level were significantly associated with overall survival (OS). Conclusions PD-L1 over-expression was not related to common driver mutations in NSCLC. Pulmonary LELC have remarkably high incidence of PD-L1 expression. PD-L1 was a negative prognostic factor for DFS in surgically resected pulmonary LELC. These findings may provide a rationale for immunotarget therapy in this virus-associated lung cancer.

Evaluations of biomarkers associated with sensitivity to 5-fluorouracil and taxanes for recurrent/advanced breast cancer patients treated with capecitabine-based first-line chemotherapy

The aim of the present study was to investigate the gene expression of biomarkers associated with the sensitivity to fluoropyrimidine and taxanes in recurrent/advanced breast cancer patients treated with first-line capecitabine chemotherapy. We evaluated the clinicopathological/prognostic significance of thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), thymidine phosphorylase (TP), class III &bgr;-tubulin (&bgr;III-tubulin), and stathmin-1 or oncoprotein-18 (STMN1). Formalin-fixed, paraffin-embedded tumor specimens from 42 patients were used for analysis of TS, DPD, TP, &bgr;III–tubulin, and STMN1 expression with a real-time reverse transcription-PCR technique. Patients were classified into the high-expression and low-expression groups according to the median value of the expression level of each biomarker. There was a significantly longer time to progression (TTP) in the high-TP group (P=0.018). The multivariate analysis revealed that the TP expression (hazard ratio for the low-TP group vs. the high-TP group, 2.873; 95% confidence interval, 1.143–7.223; P=0.025) is independent of prognostic factors for TTP. In the subgroup of patients treated with capecitabine plus taxanes as first-line chemotherapy, TTP was significantly longer in the low-&bgr;III-tubulin group (P=0.047). The gene expression of TS, DPD, and STMN1 failed to have any significant impact on the outcome. These results provide further evidence that the TP expression may be a prognostic factor in breast cancer patients treated with capecitabine-based first-line chemotherapy, and &bgr;III-tubulin can be used to predict the outcome of capecitabine in combination with taxanes as first-line chemotherapy. Therefore, these potential biomarkers should be further evaluated.

EGFR inhibitors sensitize non-small cell lung cancer cells to TRAIL-induced apoptosis

Apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can be regulated by the epidermal growth factor (EGF) signaling pathway. In this study, recombinant adenoviral vectors that encode TRAIL gene from the hTERT/RGD promoter (AdTRAIL) was combined with drugs including gefitinib, elotinib, and cetuximab that inhibit EGFR and the EGF signaling pathway in non–small cell lung cancer (NSCLC) cell lines to investigate their antitumor activity. In vitro, compared to single reagent, AdTRAIL combined with EGFR inhibitors reduced proliferation and enhanced apoptosis in H460, A549, and SW1573 cell lines. Western blot results suggested that these effects were relative to upregulation of pro-apoptosis protein BAX and down-regulation of p-AKT. In vivo, AdTRAIL combined with cetuximab resulted in a significant growth reduction in H460 xenografts without damage to the main organs of nude mice. Histological examination and TUNEL analyses of xenografts showed that cetuximab enhanced cell apoptosis induced by AdTRAIL. These results indicate that EGFR inhibitors enhanced AdTRAIL anti-tumor activity in NSCLC cell lines and that inhibiting the AKT pathway played an important role in this enhancement.

Prognostic significance of thymidylate synthase in postoperative non-small cell lung cancer patients

The aim of the present study was to investigate the clinicopathologic/prognostic significance of thymidylate synthase (TS), orotate phosphoribosyltransferase (OPRT), and thymidine phosphorylase (TP) proteins in postoperative non-small cell lung cancer (NSCLC) patients. Microarray slides from a set of 178 NSCLC patients were used for the detection of TS, OPRT, and TP expression by immunohistochemistry. The correlation between clinicopathologic factors and protein expression of three proteins was analyzed. Ninety seven carcinomas (57.4%) were TS-positive, 90 carcinomas (53.9%) were OPRT-positive, and 102 carcinomas (69.4%) were TP-positive. Compared with the TS-positive patients, the overall survival (OS) was significantly lower in the TS-negative patients (hazard ratio [HR] =1.766, 95% confidence interval [CI] =1.212–2.573, P=0.003). Significant differences between TS-positive and TS-negative patients was also observed in the following stratified analyses: 1) adenocarcinoma subgroup (HR =2.079, 95% CI =1.235–3.500, P=0.006); 2) less than 60-year-old subgroup (HR =1.890, 95% CI =1.061–3.366, P=0.031); 3) stage II/III subgroup (HR =1.594, 95% CI =1.036–2.453, P=0.034); and 4) surgery plus adjuvant therapy subgroup (HR =1.976, 95% CI =1.226–3.185, P=0.005). However, the OS was not significantly correlated with OPRT or TP protein expression. This study demonstrates that the TS level in tumor tissues may be a useful marker to predict the postoperative OS in NSCLC patients.

In vitro and in vivo efficacy of afatinib as a single agent or in combination with gemcitabine for the treatment of nasopharyngeal carcinoma

Purpose Epidermal growth factor receptor (EGFR) is usually overexpressed in nasopharyngeal carcinoma (NPC). We tested the antitumor effects of irreversible ErbB family inhibitor afatinib on human NPC using in vitro and in vivo models. Materials and methods The effect of afatinib on NPC cells was evaluated using the Cell Counting Kit 8 (CCK8) assay, flow cytometry, and Western blot analyses. The effect of afatinib, as either a single agent or in combination with gemcitabine (GEM), on tumor growth was determined using NPC tumor xenografts in mice. Results Afatinib inhibited cell growth in all three NPC cell lines tested in a dose-dependent manner. Afatinib promoted cell cycle arrest at the S and G2/M phases, and it significantly inhibited epidermal growth factor (EGF)-induced activation of EGFR and its downstream signaling factors. Co-treatment with afatinib and GEM more effectively inhibited tumor growth than either drug alone but was associated with increased toxicity. Conclusion Afatinib induced cell cycle arrest and inhibited the proliferation of NPC cell lines. Afatinib in combination with GEM demonstrated significant antitumor effect in an NPC xenograft model. The administration of afatinib with GEM in NPC needs to be modified in order to be effective and tolerable.

Development and validation of a nomogram for predicting the survival of patients with non-metastatic nasopharyngeal carcinoma after curative treatment

BackgroundThe TNM staging system is far from perfect in predicting the survival of individual cancer patients because only the gross anatomy is considered. The survival rates of the patients who have the same TNM stage disease vary across a wide spectrum. This study aimed to develop a nomogram that incorporates other clinicopathologic factors for predicting the overall survival (OS) of non-metastatic nasopharyngeal carcinoma (NPC) patients after curative treatments.MethodsWe retrospectively collected the clinical data of 1520 NPC patients who were diagnosed histologically between November 2000 and September 2003. The clinical data of a separate cohort of 464 patients who received intensity-modulated radiation therapy (IMRT) between 2001 and 2010 were also retrieved to examine the extensibility of the model. Cox regression analysis was used to identify the prognostic factors for building the nomogram. The predictive accuracy and discriminative ability were measured using the concordance index (c-index).ResultsWe identified and incorporated 12 independent clinical factors into the nomogram. The calibration curves showed that the prediction of OS was in good agreement with the actual observation in the internal validation set and IMRT cohort. The c-index of the nomogram was statistically higher than that of the 7th edition TNM staging system for predicting the survival in both the primary cohort (0.69 vs. 0.62) and the IMRT cohort (0.67 vs. 0.63).ConclusionWe developed and validated a novel nomogram that outperformed the TNM staging system in predicting the OS of non-metastatic NPC patients who underwent curative therapy.