Shaohong Huang

Epidermal Growth Factor Receptor-Containing Exosomes Induce Tumor-Specific Regulatory T Cells

The epidermal growth factor receptor (EGFR) has a close relation to lung cancer; its role in the pathogenesis of lung cancer is to be further elucidated. The results of this study indicate that about 80% exosomes purified from the LC biopsies contained EGFR; only about 2% exosomes contained EGFR in the samples from chronic lung inflammation. The purified exosomes induced tolerogenic DCs. Coculture of the tolerogenic DCs and Th0 cells generated the tumor antigen-specific regulatory T cells (Treg). The Tregs could suppress the tumor antigen specific CD8+ T cells.

Esophageal cancer-derived microvesicles induce regulatory B cells.

The role of B cells in the generation of cancer‐immune tolerance is unclear. This study aims to investigate the role of cancer‐derived microvesicles (Mvcs) in the generation of transforming growth factor (TGF)‐β+ B cells. In this study, esophageal cancer (Eca) cells were isolated from surgically removed cancer tissue. Mvcs were purified from the culture supernatant and characterized by Western blotting. The immune suppression assay was carried out with a cell culture model and flow cytometry. The results showed that Eca‐derived Mvcs were LAMP1 positive and carried MMP9. Exposure to the Mvcs induces naive B cells to differentiate into TGF‐β‐producing regulatory B cells; the latter show immune suppressor functions on CD8+ T‐cell proliferation. In conclusion, Eca‐derived Mvc can induce TGF‐β+ B cells; the latter suppress CD8+ T‐cell activities. The MMP9‐laden Mvcs may be a new therapeutic target in the treatment of Eca. Copyright

Activation of proteinase-activated receptor 2 prevents apoptosis of lung cancer cells.

The therapeutics of lung cancer (LC) is unsatisfactory. The pathogenesis of LC remains unclear. Protease-activated receptors (PAR) are involved in the immunoregulation. The present study aims to investigate the activation of PAR2 in regulation of the expression of EGFR and apoptosis of LC cells. The results showed that exposure to tryptase increased EGFR expression in A549 cells and suppressed the cell apoptosis. Tryptase also decreased the expression of Bax and increased Bcl-xL levels in A549 cells. We conclude that activation of PAR2 by tryptase can decrease the ratio of Bax/Bcl-xL and reduce the LC cell line, A549 cells, and apoptosis.

HiF-1α siRNA and Cisplatin in Combination SuppressTumor Growth in a Nude Mice Model of Esophageal Squamous Cell Carcinoma

INTRODUCTION The esophagus squamous cell carcinoma (ESCC) is one of the most deadly malignances, and a current challenge is the development of effective therapeutic agents. Our present work addressed the effect of HIF-1α siRNA alone or in combination with cisplatin on the growth of ESCC in nude mice. MATERIALS AND METHODS Xenografts were established by inoculating ESCC TE-1 cells in nude mice, and transplanted tumors were treated with HIF-1α siRNA, cisplatin alone or together. Growth was assessed by measuring tumor volume. HIF-1α mRNA and protein expression were detected using RT-PCR and immunohistochemistry, respectively. Apoptosis of ESCC TE-1 cells was analyzed by flow cytometry. RESULTS In our nude mice model, HIF-1α siRNA effectively inhibited the growth of transplanted ESCC, downregulating HIF-1α mRNA and protein expression, and inducing ESCC TE-1 cell apoptosis. Notably when combinated with cisplatin, HIF-1α siRNA showed synergistic interaction in suppressing tumor growth. Furthermore, the proportion of apoptotic cells in HIF- 1α siRNA plus cisplatin group was significantly higher than that in cisplatin or HIF-1α siRNA-treated groups (P<0.05). CONCLUSIONS Down-regulated HIF-1α expression induced by siRNA could effectively suppress the growth of transplanted ESCC in vivo. HIF-1α siRNA could enhance the cytotoxicity of cisplatin, which suggests that a combination of these two agents may have potential for therapy of advanced ESCC.

Relapsing suppurative neck abscess after chemocauterization of pyriform sinus fistula

We report a case of relapsing suppurative neck abscess due to a pyriform sinus fistula ever treated by chemocauterization. Pyriform sinus fistula is rare, and chemocauterization is an alternative microinvasive procedure. This case indicates that the possibility of recurrence following management of chemocauterization exists even after a long time and that clinical radiological assessments are necessary.

PLCE1 Suppresses p53 Expression in Esophageal Cancer Cells

The apoptotic mechanism dysfunction plays a critical role in cancer cell growth and escaping from cancer therapies; the underlying mechanisms are to be further elucidated. This study aims to investigate the role of phospholipase C epsilon 1 (PLCE1) in modulating the apoptosis mechanism in esophageal cancer (Eca) cells. The results showed that Eca cell lines, OE33 and CP-C cells expressed high levels of PLCE1. Knockdown of PLCE1 markedly increased 9.26 folds of the expression of p53 and 13.8 folds of the frequency of apoptotic CP-C cells via modulating the p53 promoter methylation.

XRCC1 and ADPRT polymorphisms associated with survival in breast cancer cases treated with chemotherapy.

AIM To investigate whether XRCC1 and ADPRT polymorphisms might be associated with outcomes of breast cancer. METHODS A prospective study was conducted with a total of 335 breast cancer patients undergoing chemotherapy consecutively collected from Jan. 2005 to Jan. 2008. Genotyping of XRCC1 and ADPRT polymorphisms was conducted by PCR-RFLP assay. RESULTS All 335 patients were followed up until death or the end of Jan. 2012, with a median follow-up period of 38.8 (2-64) months. It was shown that the variant genotype of XRCC1 399Gln/Gln was strongly significantly associated with a decreased risk of death from breast cancer, with an HR (95% CI) of 0.52 (0.28-0.91). Similarly, individuals carrying the ADPRT 762Ala/Ala demonstrated longer survival compared to ADPRT 762 Val/ Val, with an HR (95% CI) of 0.58 (0.31-0.97). Individuals with combination genotypes of XRCC1 399Gln allele and ADPRT 762Ala/Ala presented with a longer survival, the HR (95% CI) being 0.56 (0.32-0.97). CONCLUSION We found a significant association between XRCC1399Gln/ Gln and ADPRT 762Ala/Ala polymorphisms and clinical outcomes. These two genotypes could be used as a surrogate markers of clinical outcome in glioma cases receiving chemotherapy.

Maintenance erlotinib improves clinical outcomes of unresectable advanced non-small cell lung cancer: A meta-analysis of randomized controlled trials.

The aim of this study was to evaluate the efficacy and safety of erlotinib as maintenance therapy in patients with unresectable non-small cell lung cancer (NSCLC) by evidence-based methodology. Six eligible studies including 4,372 patients were analyzed. Erlotinib was administered to 2,191 patients as maintenance treatment, while the remaining patients received a placebo or observation only. The meta-analysis was performed using Reviewer Manager Version 5.12 software. Compared with the control group, maintenance erlotinib improved progression-free survival (PFS) and overall survival (OS) with moderate heterogeneity. Results from the random effects model analysis for OS were not in concordance with the difference observed in the fixed effects model analysis. Administration of erlotinib only after chemotherapy obtained a higher objective response rate (ORR). Safety analyses indicated a slight increase in side-effects. The most common adverse events (AEs) were diarrhea and rash, which were usually manageable. There was no significant difference in treatment-related deaths. Erlotinib produced significant clinical benefits with acceptable toxicity as a maintenance strategy in patients with unresectable NSCLC, particularly when sequentially administered with chemotherapy. However, more well-designed randomized control trials (RCTs) are required to identify patients that may derive greater benefits from maintenance with erlotinib, and whether the use of erlotinib as maintenance therapy is more efficient than second-line treatment should also be investigated.

Airway epithelial cell-derived insulin-like growth factor-1 triggers skewed CD8+ T cell polarization

Skewed CD8+ T cell responses are important in airway inflammation. This study investigates the role of the airway epithelial cell‐derived insulin‐like growth factor 1 (IGF1) in contributing to CD8+ T cell polarization. Expression of IGF1 in the airway epithelial cell line, RPMI2650 cells, was assessed by quantitative real time RT‐PCR and Western blotting. The role of IGF1 in regulating CD8+ T cell activation was observed by coculture of mite allergen‐primed RPMI2650 cells and naïve CD8+ T cells. CD8+ T cell polarization was assessed by the carboxyfluorescein succinimidyl ester‐dilution assay and the determination of cytotoxic cytokine levels in the culture medium. Exposure to mite allergen, Der p1, increased the expression of IGF1 by RPMI2650 cells. The epithelial cell‐derived IGF1 prevented the activation‐induced cell death by inducing the p53 gene hypermethylation. Mite allergen‐primed RPMI2650 cells induced an antigen‐specific CD8+ T cell polarization. We conclude that mite allergens induce airway epithelial cell line, RPMI2650 cells, to produce IGF1; the latter contributes to antigen‐specific CD8+ T cell polarization.

Time Delay of Microdialysis in vitro.

Background: Microdialysis is a specific and local sampling method to collect free molecules from the extracellular fluid, however, there are no reports on time delay issues of microdialysis applications. Aims: This study was to check the time gap between the start of target molecule changes in detected fluid and corresponding stable concentration formation in the sampled dialysate. Materials and Methods: A designated microdialysis system for free calcium ion was set up in vitro and perfused with saline. The dialysate was diluted synchronously, and collected in a vial every 10 min. The free calcium concentration [Ca++] of the sample was measured by an atomic absorption spectrophotometer. A signal-switching method was introduced to mimic the target molecule [Ca++] changes in the detected fluid, standard calcium solution and saline. Results: There was a notable lag in dialysates [Ca++] for both uprising and down going course in spite of instant switching between the detected fluids. The recovery time (RT) of the microdialysis system was extrapolated to be 20 min for [Ca++] detection. Conclusions: With 10 min sampling interval, [Ca++] time delay of the microdialysis system existed, and could not be estimated precisely beforehand. The signal-switching method was applicable for RT calibration in vitro with a dedicated microdialysis system.