RUNX3/H3K27me3 Co-Expression Defines a Better Prognosis in Surgically Resected Stage I and Postoperative Chemotherapy-Naive Non-Small-Cell Lung Cancer

The purpose of this study is to investigate the significance of RUNX3/H3K27me3 co-expression in surgically resected non-small-cell lung cancer (NSCLC) patients. Using tissue microarray (TMA), immunohistochemistry, fluorescent double immunostaining, and western blotting, 208 NSCLC and 5 benign pulmonary patients were studied of their expression of runt-related transcription factor 3 (RUNX3), trimethylated histone H3 at lysine 27 (H3K27me3), enhancer of zeste homolog 2 (EZH2), and Ki-67. Apoptotic index in cancerous tissue was evaluated via TdT-mediated dUTP-biotin nick end labeling (TUNEL). The correlation between clinicopathologic parameters and overall survival was determined by Cox regression and Kaplan–Meier survival estimates and log-rank test. GEPIA and KM plotter were used for validation of some survival analyses. As a result, together with other regular prognostic factors, RUNX3/H3K27me3 co-expression was found to be closely correlated with better prognosis in either pTNM-I or POCT-naive NSCLC patients, which might partially result from a higher cancerous apoptotic index. In conclusion, RUNX3/H3K27me3 co-expression defined some specific NSCLC population with better prognosis and longer OS and could probably be used as a biomarker in the prediction of better postoperative outcomes.

Ophiopogon japonicus inhibits radiation-induced pulmonary inflammation in mice

Background

Radiation-induced lung injury, including the acute pulmonary inflammation and chronic pulmonary fibrosis remains the major complication of thoracic radiotherapy.

Methods

In this study, we assessed the effects of Ophiopogon japonicus (O. japonicas) in inhibiting the radiation-induced pulmonary inflammation through an acute lung injury mouse model using C57BL/6 mice that received 18 Gy irradiation to the thoracic region. Starting at 4 days before radiation, mice were treated with O. japonicus or dexamethasone combined with cephalexin or vehicle daily for 14 days.

Results

Exposure to radiation resulted in pulmonary inflammation in mice, but treatment with O. japonicus or dexamethasone-cephalexin could both significantly reduce radiation-induced pulmonary inflammation through inhibition of IL-6, TNF-α, TGF-β1, hydroxyproline, MDA, MMP-2 and TIMP-2 in plasma or lung tissue. In addition, through analyzing tissue damage, cytokines and inflammation-related protein at 12 weeks after irradiation, we found that the protective effect of O. japonicus was more enduring than dexamethasone-cephalexin.

Conclusions

As radiation-induced lung injury is a major obstacle in thoracic radiotherapies and seriously affect the quality of patients' life. Application of O. japonicus may be a novel strategy to manage radiation-induced pulmonary inflammation.

Long Noncoding RNA FAM201A Mediates the Radiosensitivity of Esophageal Squamous Cell Cancer by Regulating ATM and mTOR Expression via miR-101

Background: The aim of the present study was to identify the potential long non-coding (lnc.)-RNA and its associated molecular mechanisms involved in the regulation of the radiosensitivity of esophageal squamous cell cancer (ESCC) in order to assess whether it could be a biomarker for the prediction of the response to radiotherapy and prognosis in patients with ESCC.

Methods: Microarrays and bioinformatics analysis were utilized to screen the potential lncRNAs associated with radiosensitivity in radiosensitive (n = 3) and radioresistant (n = 3) ESCC tumor tissues. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed in 35 ESCC tumor tissues (20 radiosensitive and 15 radioresistant tissues, respectively) to validate the lncRNA that contributed the most to the radiosensitivity of ESCC (named the candidate lncRNA). MTT, flow cytometry, and western blot assays were conducted to assess the effect of the candidate lncRNA on radiosensitivity in vitro in ECA109/ECA109R ESCC cells. A mouse xenograft model was established to confirm the function of the candidate lncRNA in the radiosensitivity of ESCC in vivo. The putative downstream target genes regulated by the candidate lncRNA were predicted using Starbase 2.0 software and the TargetScan database. The interactions between the candidate lncRNA and the putative downstream target genes were examined by Luciferase reporter assay, and were confirmed by PCR.

Results: A total of 113 aberrantly expressed lncRNAs were identified by microarray analysis, of which family with sequence similarity 201-member A (FAM201A) was identified as the lncRNA that contributed the most to the radiosensitivity of ESCC. FAM201A was upregulated in radioresistant ESCC tumor tissues and had a poorer short-term response to radiotherapy resulting in inferior overall survival. FAM201A knockdown enhanced the radiosensitivity of ECA109/ECA109R cells by upregulating ataxia telangiectasia mutated (ATM) and mammalian target of rapamycin (mTOR) expression via the negative regulation of miR-101 expression. The mouse xenograft model demonstrated that FAM201A knockdown improved the radiosensitivity of ESCC.

Conclusion: The lncRNA FAM201A, which mediated the radiosensitivity of ESCC by regulating ATM and mTOR expression via miR-101 in the present study, may be a potential biomarker for predicting radiosensitivity and patient prognosis, and may be a therapeutic target for enhancing cancer radiosensitivity in ESCC.

Growth, clonability, and radiation resistance of esophageal carcinoma-derived stem-like cells

OBJECTIVE

To separate/enrich tumor stem-like cells from the human esophageal carcinoma cell line OE-19 by using serum-free suspension culture and to identify their biological characteristics and radiation resistance.

METHODS

OE-19 cells were cultivated using adherent and suspension culture methods. The tumor stem-like phenotype of CD44 expression was detected using flow cytometry. We examined growth characteristics, cloning capacity in soft agar, and radiation resistance of 2 groups of cells.

RESULTS

Suspended cells in serum-free medium formed spheres that were enriched for CD44 expression. CD44 was expressed in 62.5% of suspended cells, but only in 11.7% of adherent cells. The suspended cells had greater capacity for proliferation and colony formation in soft agar than the adherent cells. When the suspended and adherent cells were irradiated at 5 Gy, 10 Gy, or 15 Gy, the proportion of CD44+ suspended cells strongly and weakly positive for CD44 was 77.8%, 66.5%, 57.5%; and 21.7%, 31.6%, 41.4%, respectively. In contrast, the proportion of CD44+ adherent cells strongly positive for CD44 was 18.9%, 14.%, and 9.95%, respectively. When the irradiation dose was increased to 30 Gy, the survival of the suspended and adherent cells was significantly reduced, and viable CD44+ cells were not detected.

CONCLUSION

Suspended cell spheres generated from OE-19 esophageal carcinoma cells in serum-free stem medium are enriched in tumor stem-like cells. CD44 may be a marker for these cells.

Preliminary study of the internal margin of the gross tumor volume in thoracic esophageal cancer

PURPOSE

To measure the displacement of the tumor of the gross tumor volume (GTV) of thoracic esophageal cancer in the calm states of end-inspiration and end-expiration for determining the internal margin of the GTV (IGTV).

METHODS

Twenty-two patients with thoracic esophageal cancer who were unable to undergo surgery were identified in our hospital. The patients received radiotherapy. By using 16-slice spiral computed tomography (CT), we acquired the calm states of end-inspiration and end-expiration. The displacement and volume changes in tumor target volume were measured, and the changes were analyzed to determine if these were associated with the tidal volume and the location and length of the target volume V. In the end, we analyzed the displacement of tumor target volume and calculated the internal margin of the GTV by empirical formula.

RESULTS

The average tidal volume was 463.6 ml. The average GTV at end-inspiration was 33.3 ml and at end-expiration was 33.35 ml. Three was not any significant between two groups (T=-0.034, P>0.05). The IGTV (X-axis direction) was 3.09 mm for the right sector and 4.08 mm for the left border; the IGTV (Z-axis direction) was 3.96 mm for the anterior border and 2.83 mm for the posterior border; and the IGTV (Y-axis direction) was 7.31 mm for the upper boundary (head direction) and 10.16 mm for the lower boundary (feet direction). The motion of the GTV showed no significant correlation with the tidal volume of patients and the length of the tumor, but in relation to the tumor location, the displacement of the lower thoracic and the middle thoracic target volumes occurred in the direction of the anterior and right, which were not significantly different (T=0.859, 0.229, P>0.05) The significant differences were observed for the other directions (P<0.05).

CONCLUSIONS

Because of respiratory and organ movements, the displacement of the tumor target volume was different in all directions. Therefore, we recommend that expansion of the planning target volume during clinical radiation treatment needs to include the displacement of the tumor target volume caused by respiratory and organ movements during each radiotherapy session.