MicroRNAs (miRNAs), noncoding RNAs 21-25 nucleotides in length, regulate gene expression primarily at the posttranscriptional level. Growing evidence suggests that miRNAs are aberrantly expressed in many human cancers, and that they play significant roles in carcinogenesis and cancer progression. A search for miRNAs with a tumor-suppressive function in esophageal squamous cell carcinoma (ESCC) was performed using the miRNA expression signatures obtained from ESCC clinical specimens. A subset of 15 miRNAs was significantly downregulated in ESCC. A comparison of miRNA signatures from ESCC and our previous report identified 4 miRNAs that are downregulated in common (miR-145, miR-30a-3p, miR-133a and miR-133b), suggesting that these miRNAs are candidate tumor suppressors. Gain-of-function analysis revealed that 3 transfectants (miR-145, miR-133a and miR-133b) inhibit cell proliferation and cell invasion in ESCC cells. These miRNAs (miR-145, miR-133a and miR-133b), which have conserved sequences in the 3 0 UTR of FSCN1 (actin-binding protein, Fascin homolog 1), inhibited FSCN1 expression. The signal from a luciferase reporter assay was significantly decreased at 2 miR-145 target sites and 1 miR-133a/b site, suggesting both miRNAs directly regulate FSCN1. An FSCN1 loss-of-function assay found significant cell growth and invasion inhibition, implying an FSCN1 is associated with ESCC carcinogenesis. The identification of tumor-suppressive miRNAs, miR-145, miR-133a and miR-133b, directly control oncogenic FSCN1 gene. These signal pathways of ESCC could provide new insights into potential mechanisms of ESCC carcinogenesis.Human esophageal cancer occurs worldwide with a variable geographic distribution. The disease ranks eighth in order of occurrence and sixth as the leading cause of cancer mortality, affecting men more than women. 1 There are 2 main forms, each with distinct etiologic and pathologic characteristics: esophageal squamous cell carcinoma (ESCC) and adenocarcinoma. ESCC is the most frequent subtype of esophageal cancer, although the incidence of adenocarcinoma in the western world is increasing faster than other malignancies. ESCC is one of the most aggressive and lethal malignancies in eastern Asia. Because most cases of ESCC are not diagnosed until the disease is at an advanced stage, the overall 5-year survival rate is very poor.2-4 Recently, the combination of chemotherapy and radiotherapy, alone or as an adjunct to surgery, has improved the prognosis of ESCC patients. 5,6 Research over the last 20 years has identified a number of oncogenic and tumor-suppressor proteins that are associated with the induction of ESCC. 7,8 However, molecular indicators of the origin of cellular deregulation in ESCC have not been identified. Elucidation of the molecular pathways involved in ESCC carcinogenesis could lead to improvements in disease diagnosis and therapy.MicroRNAs (miRNAs) are a class of naturally occurring small (21-25 nucleotides) noncoding RNAs. Mature miRNAs play important regulatory roles in cell growth, p...

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Exosomes play important roles in cancer progression. Although its contents (e.g., proteins and microRNAs) have been focused on in cancer research, particularly as potential diagnostic markers, the exosome behavior and methods for exosome quantification remain unclear. In the present study, we analyzed the tumor-derived exosome behavior and assessed the quantification of exosomes in patient plasma as a biomarker for esophageal squamous cell carcinoma (ESCC). A CD63-GFP expressing human ESCC cell line (TE2-CD63-GFP) was made by transfection, and mouse subcutaneous tumor models were established. Fluorescence imaging was performed on tumors and plasma exosomes harvested from mice. GFP-positive small vesicles were confirmed in the plasma obtained from TE2-CD63-GFP tumor-bearing mice. Patient plasma was collected in Chiba University Hospital (n=86). Exosomes were extracted from 100 µl of the plasma and quantified by acetylcholinesterase (AChE) activity. The relationship between exosome quantification and the patient clinical characteristics was assessed. The quantification of exosomes isolated from the patient plasma revealed that esophageal cancer patients (n=66) expressed higher exosome levels than non-malignant patients (n=20) (P=0.0002). Although there was no correlation between the tumor progression and the exosome levels, exosome number was the independent prognostic marker and low levels of exosome predicted a poor prognosis (P=0.03). In conclusion, exosome levels may be useful as an independent prognostic factor for ESCC patients.

At the moment, there is no sensitive clinical test for detecting early-stage colorectal cancer (CRC). Target proteomics has enabled high-throughput verification of hundreds of biomarker candidate proteins. Using this technology, we verified 725 previously reported CRC biomarker candidate proteins that are functionally correlated with CRC in extracellular vesicles (EVs) from patients. Of these, 356 proteins were quantified, and 34 peptides (22 proteins) showed significant differences in the serum EVs between healthy controls and CRC patients of two independent cohorts (n = 77 and 84). These peptides were evaluated as single or multiple markers, and four single peptides in annexin family proteins and eight combinations of peptides showed area under the curve > 0.9 for discriminating between healthy controls and CRC patients. The sensitivities of annexins A3, A4, and A11 peptides for detecting early-stage CRC greatly exceed those of carcinoembryonic antigen. These peptides are promising biomarkers for early detection of CRC.

The expression of microRNA-203 (miR-203) in esophageal squamous cell carcinoma (ESCC) tissues is remarkably lower than that in non‑ESCC tissues. We investigated how miR-203 could influence the development of ESCC cells. Our analyses revealed that miR-203 inhibited the migration and invasion of ESCC cells. Genome-wide gene expression data and target site inhibition assays showed that miR-203 appears to directly regulate LIM and SH3 protein 1 (LASP1). The knockdown of LASP1 resulted in inhibition of the migration and invasion of ESCC cells. Our results suggest that miR-203 and its target LASP1, may be associated with the progression of ESCC. In clinical ESCC specimens, the expression levels of miR-203, which were lower compared to those in normal tissues, were inversely correlated with the mRNA expression levels of LASP1. Moreover, we found that there was a significant correlation between the expression levels of miR-203 and the relapse‑free survival. The identification of a cancer network regulated by miR-203 could provide new insights into the potential mechanisms of the progression of ESCC.

Background Postoperative docetaxel plus S-1 (DS) chemotherapy is expected to be the standard therapeutic strategy for pStage III gastric cancer based on the results of the JACCRO GC-07 study. Neoadjuvant chemotherapy (NAC) is thought to have several advantages over adjuvant settings. Objective This study aimed to compare the efficacies of NAC DS and the surgery-first strategy for advanced gastric cancer patients with D2 gastrectomy. Methods This was a retrospective, single-institution observational study. Of 171 patients with locally advanced (cStage IIB or III) gastric cancer who underwent curative D2 gastrectomy and received NAC DS and/or S-1 adjuvant chemotherapy between 2011 and 2017, 76 (after propensity score matching for 132 patients who met the eligibility criteria) were enrolled in this study. The 3-year progression-free survival (PFS) rate was used to directly compare efficacies between NAC DS patients and surgery-first patients. Results The 3-year PFS rates for the NAC DS group were significantly higher than those for the surgery-first group (80.0 vs. 58.7; p = 0.037), and the progression hazard ratio of the NAC DS group compared with the surgery-first group was 0.394 (95% confidence interval 0.159–0.978; p = 0.045). Conclusions The NAC DS group showed a high 3-year PFS compared with the surgery-first group, with standard S-1 postoperative chemotherapy or observation. NAC DS can be expected to be beneficial as the standard therapy for advanced gastric cancer and should be adopted for the test arm of a randomized controlled phase III trial. Electronic supplementary material The online version of this article (10.1245/s10434-019-07299-7) contains supplementary material, which is available to authorized users.

BACKGROUND:The expression of Fra-1 (Fos related antigen 1) involves tumor progression and invasion, and its gene ablation could suppress the invasive phenotypes of human tumor cells. The authors investigated the significance of Fra-1 expression in esophageal squamous cell carcinoma (ESCC) and studied the effect of its down-regulation on cell proliferation, motility, and invasion. METHODS: Surgical specimens from 164 patients with ESCC were evaluated. Fra-1 expression in the primary tumor along with metastatic lymph nodes was compared among various clinicopathological characteristics, and overall survival was analyzed. The rate and intensity of Fra-1 immunoreactivity were also investigated. The molecular role of Fra-1 was assessed by its down-regulation in human ESCC cell lines. RESULTS: Fra-1 expression was positive in 127 (77.4%) ESCC patients. Immunoreactivity was localized to the marginal areas of the ESCC tumors. Positive Fra-1 expression correlated with depth of tumor, lymph node metastasis, stage, and infiltrative growth pattern. A significant difference was seen in the survival between tumors with and without Fra-1, and positive Fra-1 expression was revealed to be an independent factor related to poor prognosis. Patients with metastatic lymph nodes with positive Fra-1 expression presented decreased survival compared with negative Fra-1 expression. After the down-regulation of Fra-1 expression, a significant decrease in cell proliferation, motility, and invasion was observed. CONCLUSIONS: This study demonstrated ESCC patients positive for Fra-1 to be associated with poor prognosis. The findings also suggest that Fra-1 regulation may play an important role in the progression of ESCC.

We tested a new therapeutic modality for head and neck and esophageal cancers, a combination of direct intratumoral (i.t.) administration of dendritic cells (DCs) and radiation therapy (RT) in mouse squamous cell carcinoma (SCC). We also evaluated the functions of gp96, which can enhance systemic antitumor activity, and the mechanism of the abscopal effect. Mouse SCC cells (1x10 5), SCCVII, were inoculated into the left femur of C3H/He mice subcutaneously, and also similarly inoculated into chest subcutaneous tissue. Only the left femur tumor was exposed to 4 or 10 Gy of ionizing radiation, and then 1x10 6 DCs i.t. was injected only into the femur tumor. Following this procedure, tumor volumes of the femur and chest were measured. We evaluated whether gp96 could enhance the antitumor effect. With DCs i.t. and RT, tumor growth was markedly suppressed. Tumor growth of non-treated tumors were also suppressed, indicating that the combination therapy of DCs and RT evoked systemic antitumor activity. In vitro, the enhancement of gp96 expression was strongly detected by immunostaining after irradiation, DCs with gp96 induced strong cytotoxic activity in vitro, and tumor growth inhibition was observed by direct i.t. injection of gp96. A combination of DCs i.t. and RT can induce a strong antitumor effect not only against treated local tumor but also against non-treated distant tumor, indicating that this treatment can evoke a strong systemic antitumor effect. Gp96 is thought to be one of the target molecules to explain the abscopal effect.