Prognostic Impact of Hepatic Steatosis Evaluated by CT on Immunotherapy for Gastric Cancer: Associations with Sarcopenia, Systemic Inflammation, and Hormones.

INTRODUCTION: Immune checkpoint inhibitors (ICIs) are expected to improve the prognosis of gastric cancer (GC). Also, hepatic steatosis has been reported to be associated with cancer cachexia and is expected to be a cancer biomarker. The purpose of this study was to evaluate prognostic impact of hepatic steatosis in ICI therapy for GC. METHODS: Unresectable or recurrent GC treated with ICIs was investigated. Using unenhanced CT, the liver-to-spleen CT attenuation ratio (LSR) was calculated as a parameter of hepatic steatosis. LSR was compared with the presence of sarcopenia and inflammatory markers including neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-lymphocyte ratio (MLR). These parameters were also compared with disease-specific survival (DSS) and progression-free survival (PFS). Associations of LSR with insulin-like growth factor 1 (IGF-1) and growth hormone were also evaluated. RESULTS: A total of 70 patients were investigated. LSR of sarcopenia patients was significantly lower than that of non-sarcopenic ones (p = 0.02). LSR showed significant negative correlations with NLR, PLR, and MLR (p = 0.003, 0.03, 0.01, respectively). Lower LSR was significantly associated with a higher level of serum IGF-1 (p = 0.03). In univariate analysis, LSR was significantly correlated with DSS and PFS (both p < 0.0001), and multivariate analysis demonstrated that LSR was the independent prognostic factor for both DSS and PFS (both p = 0.01). ROC analysis demonstrated that LSR >1.263 was a good predictive marker for favorable DSS (>5.3 months) with an AUC of 0.80. CONCLUSION: Hepatic steatosis can be a promising prognostic biomarker for ICI therapy of GC, associated with sarcopenia and the elevation of inflammatory markers. Our data suggested that GC with steatohepatitis might be less responsive to ICI therapy.

Analysis of patients with colorectal cancer shows a specific increase in serum anti-ING1 autoantibody levels.

Colorectal cancer (CRC) is the third most prevalent cancer in the world, yet the sensitivity and specificity of biomarkers for CRC diagnosis are insufficient. In the present study, we performed a protein microarray screening method to identify antibody markers for CRC. Inhibitor of growth family 1 (ING1) was identified as a candidate tumor antigen for CRC using protein microarrays (ProtoArray). Subsequent amplified luminescence proximity homogeneous assay-linked immunosorbent assay using recombinant ING1 protein showed that the serum levels of anti-ING1 antibodies were increased not only in patients with CRC but also in those with esophageal cancer (EC), gastric cancer (GC), breast cancer (BrC), and pancreatic cancer (PC) compared with those of healthy donors (HDs). Antibodies against the ING1 amino acids between 239 and 253 were present at significantly higher levels in patients with CRC than in those with EC, GC, BrC, or PC. Anti-ING1 antibody levels were significantly higher in the patients with CRC at any stages than in the HDs. Immunohistochemical staining revealed higher expression of ING1 protein in CRC cells than in the adjacent normal tissues. In luciferase reporter assays using a CRC cell line, ING1 augmented p53-mediated NOXA promoter activity but attenuated p53-stimulated Bax, p21, and PUMA promoter activities. Consequently, serum anti-ING1 antibodies can be used for sensitive and specific diagnoses of CRC.

Combinational antibody detection approach increases the clinical validity of colorectal cancer screening.

BACKGROUND: At different stages of the disease, biomarkers can help to determine disease progression and recurrence and provide a personalized indicator of therapeutic effectiveness. The serological identification of antigens by recombinant cDNA expression cloning (SEREX) has identified five SEREX antigens. RESULTS: Compared with healthy donors, anti-FIRΔexon2 and anti-SOHLH antibodies (Abs) in the sera of patients with colorectal cancer (CRC) were markedly higher. Furthermore, no correlation was noted between five SEREX antigens and the three tumor markers (CEA, CA19-9, and anti-p53 Abs), indicating that anti-FIRΔexon2 Abs are an independent candidate marker for patients with CRC. Generally, the levels of anti-FIRΔexon2 Abs combined with clinically available tumor markers were determined to be significantly higher compared with CEA, CA19-9. Moreover, in early-stage CRC, the levels of anti-FIRΔexon2 Abs combined with existing tumor markers were higher than those of CEA, CA19-9. CONCLUSION: Due to the highly heterogeneous nature of CRC, a single tumor marker is unlikely to become a standalone diagnostic test due to its commonly insufficient sensitivity and/or specificity. Using a combination antibody detection approach of tumor markers for CRC diagnosis has the potential to be an effective approach. Therefore, the use of serum protein biomarker candidates holds promise for the development of inexpensive, noninvasive, and inexpensive tests for the detection of CRC.

HIF-1α stimulates the progression of oesophageal squamous cell carcinoma by activating the Wnt/ß-catenin signalling pathway.

BACKGROUND: This study aimed to clarify the significance of the crosstalk between hypoxia-inducible factor-1α (HIF-1α) and the Wnt/ß-catenin pathway in oesophageal squamous cell carcinoma (ESCC). METHODS: The oncogenic role of HIF-1α in ESCC was investigated using in vitro and in vivo assays. The clinicopathological significance of HIF-1α, ß-catenin and TCF4/TCF7L2 in ESCC were evaluated using quantitative real-time PCR and immunohistochemistry. RESULTS: The expression level of HIF-1α, ß-catenin, and TCF4/TCF7L2 in T.Tn and TE1 cell lines were elevated under hypoxia in vitro. HIF-1α knockdown suppressed proliferation, migration/invasion and epithelial-mesenchymal transition (EMT) progression, induced G0/G1 cell cycle arrest, promoted apoptosis and inhibited 5-fluorouracil chemoresistance in vitro. In vivo assays showed that HIF-1α is essential in maintaining tumour growth, angiogenesis, and 5-fluorouracil chemoresistance. Mechanically, we identified the complex between HIF-1α and ß-catenin, HIF-1α can directly bind to the promoter region of TCF4/TCF7L2. The mRNA level of HIF-1α, ß-catenin and TCF4/TCF7L2 were increased in ESCC tumour tissues compared to the corresponding non-tumour tissues. High levels of HIF-1α and TCF4/TCF7L2 expression were correlated with aggressive phenotypes and poor prognosis in ESCC patients. CONCLUSIONS: HIF-1α serves as an oncogenic transcriptional factor in ESCC, probably by directly targeting TCF4/TCF7L2 and activating the Wnt/ß-catenin pathway.

Soluble PD-L1 Concentration Is Proportional to the Expression of PD-L1 in Tissue and Is Associated with a Poor Prognosis in Esophageal Squamous Cell Carcinoma.

INTRODUCTION: We determined the soluble programmed cell death-1 ligand-1 (sPD-L1) concentration in patients with esophageal squamous cell carcinoma (ESCC), and confirmed the PD-L1 expression in resected specimens. METHODS: Blood samples were collected from 73 patients with histologically proven ESCC. The serum levels of sPD-L1 were measured using an enzyme-linked immunosorbent assay. The correlations between the sPD-L1 concentration and the expression of PD-L1 in tumor specimens and tumor depth, lymph node metastasis, disease stage, and various laboratory data were assessed. RESULTS: sPD-L1 levels in patients with high PD-L1 expression levels in tumor tissue were significantly higher than in patients with low PD-L1 expression levels (p = 0.042). The OS of the sPD-L1-high group was significantly worse than that of the low group (p = 0.028). Similarly, patients in whom a tissue specimen was PD-L1-positive group showed significantly poorer OS. CONCLUSION: The sPD-L1 concentration was correlated with the PD-L1 expression in tissues. Patients with PD-L1-positive tissue specimens showed significantly higher sPD-L1 levels in comparison to PD-L1-negative cases. Furthermore, patients with high sPD-L1 expression levels had a significantly worse prognosis than those with low sPD-L1 expression levels, and patients with a PD-L1-positive tissue specimen had a significantly worse prognosis than patients in whom the tissue specimen showed a low PD-L1 expression level.

Metformin-Induced Heat Shock Protein Family A Member 6 Is a Promising Biomarker of Esophageal Squamous Cell Carcinoma.

INTRODUCTION: Antidiabetic drug metformin exerts various antitumor effects on different cancers. Esophageal squamous cell carcinoma (ESCC) is an intractable digestive organ cancer and new treatment strategy is required. In this study, we performed a comprehensive gene expression analysis of ESCC cell lines treated with metformin, which provided helpful information on the antitumor effects of metformin in ESCC. Next, we selected a promising gene among them and examined its effects on ESCC properties. METHODS: We examined metformin-induced mRNA expression changes in two human ESCC cell lines by performing next-generation sequencing (NGS) and pathway analysis. Heat shock protein family A (Hsp70) member 6 (HSPA6) expression in surgical specimens obtained from 83 ESCC patients who underwent curative operations was evaluated immunohistochemically and analyzed. RESULTS: Metformin upregulated mRNA expression of the many genes, including HSPA6, a cancer immune-related gene, and inhibited mRNA expression of the other many genes. Pathway analysis indicated major canonical pathways and upstream regulators related to metformin. The result indicated HSPA6 as a promising biomarker. HSPA6 expression correlated with disease-free survival (DFS) of the patients with all stage ESCC (p = 0.021), especially with stage I/II ESCC (p < 0.001). With stage III, low HSPA6 expression was not associated with poor DFS (p = 0.918). Multivariate analysis indicated that independent low HSPA6 expression was an independent poor prognostic factor of stage I/II ESCC (p < 0.001). However, HSPA6 expression did not correlate with the clinicopathological characteristics, including age, sex, tumor depth, lymph node metastasis, tumor stage, and tumor markers of the patients with stage I/II ESCC. CONCLUSIONS: This NGS analysis detected prospective candidate genes, including HSPA6. Our results indicate that HSPA6 is a promising biomarker of the recurrence risk of stage I/II ESCC. Further studies on HSPA6 would lead to better treatment.

Comparison of estimated treatment effects between randomized controlled trials, case-matched, and cohort studies on laparoscopic versus open distal gastrectomy for advanced gastric cancer: a systematic review and meta-analysis.

PURPOSE: In actual surgical research, case-matched studies are frequently conducted as an alternative to randomized controlled trials (RCTs). However, it is still unclear what differences there are between RCTs and case-matched studies in upper gastrointestinal surgery, and clarifying them is a very important clinical issue. Thus, the purpose of this study was to investigate estimated treatment effects between RCTs, case-matched studies, and cohort studies regarding laparoscopic distal gastrectomy (LDG) for advanced gastric cancer (AGC). METHODS: We searched the PubMed, Cochrane Central Register of Controlled Trials, and Web of Science databases for studies that compared LDG versus open distal gastrectomy for AGC published from the inception of the databases until July 2021. A meta-analysis was performed using the Review Manager version 5.3 software program from the Cochrane Collaboration, and six short-term outcomes and three long-term outcomes were assessed. RESULTS: Twenty-three studies with 13698 patients were included. There was no difference in estimated treatment effects between RCTs and case-matched studies for all outcomes except for the number of retrieved lymph nodes and postoperative complications. In terms of intraoperative blood loss, postoperative hospital stay, number of retrieved lymph nodes, and recurrence, observational studies tended to overestimate the treatment effects. CONCLUSION: The estimated treatment effects of LDG for AGC in the case-matched study were almost the same as in the RCTs. However, to assess the true magnitude of the treatment effect, the design and actual implementation of the analysis must be critically evaluated.

Biased expression of mutant alleles in cancer-related genes in esophageal squamous cell carcinoma.

BACKGROUND: Recent progress of large-scale international studies has provided comprehensive catalogs of somatic mutations in cancers. Additionally, it has become evident that allelic imbalance in the abundance of somatic mutations between DNA and RNA were pervasive in various types of cancer. However, the allelic imbalance of the abundance of somatic mutations in esophageal squamous cell carcinoma (ESCC) has not been fully analyzed. METHODS: We performed exome sequencing for 25 Japanese patients with ESCC to detect a comprehensive catalog of somatic mutations in ESCC. Additionally, we performed mRNA sequencing to evaluate the allelic imbalance of the identified somatic mutations at the transcriptional level by comparing the mutant allele frequencies between RNA and DNA. RESULTS: The exome sequencing showed that TP53 and ZNF750 were significantly mutated genes. The expression levels of TP53 and ZNF750 were different depending on the mutation status. In almost all the tumors with missense mutations in TP53 and ZNF750, the mutant allele frequencies were higher in the RNA sequencing than those in the exome sequencing, indicating that the mutant alleles were preferentially expressed. By examining the allelic imbalances for all the identified missense mutations, we demonstrated that genes showing preferential expressions of the mutant alleles were involved in the pathways including cell cycle, cell death, and chromatin modification. CONCLUSIONS: The results of this study suggest that the allelic imbalance of the abundance of somatic mutations plays important roles in the initiation and progression of ESCC by modulating cancer-related biological pathways.

Anti-FIRΔexon2 autoantibody as a novel indicator for better overall survival in gastric cancer.

There is no clinically available biomarker for efficiently indicating the overall survival or therapy response of gastric cancer (GC). The autoantibodies (Abs) in the sera of anti-far-upstream element-binding protein-interacting repressor-lacking exon2 (FIRΔexon2), anti-sorting nexin 15, and anti-spermatogenesis and oogenesis-specific basic helix-loop-helix 1 were markedly higher in GC patients than in healthy donors (HDs). These Abs were identified by large-scale serological identification of antigens by recombinant cDNA expression cloning screenings and their expression levels were evaluated by amplified luminescence proximity homogeneous assay. In particular, compared with age-matched HDs, the level of anti-FIRΔexon2 Abs in GC patients was significantly higher (P < .001). The Spearman's rank correlation analysis between anti-FIRΔexon2 Abs and clinically available tumor markers such as carcinoembryonic antigen (CEA) was statistically insignificant, indicating that FIRΔexon2 Abs is an independent biomarker. We performed receiver-operating curve analysis to evaluate the anti-FIRΔexon2 Ab as a candidate biomarker with CEA and carbohydrate antigen 19-9 (CA19-9). The overall survival of GC patients with high anti-FIRΔexon2 Abs titer was significantly favorable (P = .04) than that of GC patients who were below detection level of anti-FIRΔexon2 Abs. However, clinical stages were not apparently correlated with the levels of anti-FIRΔexon2 Ab, CEA, and CA19-9. In conclusion, anti-FIRΔexon2 Abs detected in GC patients is a potential biomarker for monitoring a better prognosis. Hence, anti-FIRΔexon2 Abs is a promising biomarker for indicating better overall survival of gastric cancer patients.

Quantification of Structural Heterogeneity Using Fractal Analysis of Contrast-Enhanced CT Image to Predict Survival in Gastric Cancer Patients.

BACKGROUND: Malignant tumor essentially implies structural heterogeneity. Fractal analysis of medical imaging has a potential to quantify this structural heterogeneity in the tumor AIMS: The purpose of this study is to quantify this structural abnormality in the tumor applying fractal analysis to contrast-enhanced computed tomography (CE-CT) image and to evaluate its biomarker value for predicting survival of surgically treated gastric cancer patients. METHODS: A total of 108 gastric cancer patients (77 men and 31 women; mean age: 69.1 years), who received curative surgery without any neoadjuvant therapy, were retrospectively investigated. Portal-phase CE-CT images were analyzed with use of a plug-in tool for ImageJ (NIH, Bethesda, USA), and the fractal dimension (FD) in the tumor was calculated using a differential box-counting method to quantify structural heterogeneity in the tumor. Tumor FD was compared with clinicopathologic features and disease-specific survival (DSS). RESULTS: High FD value of the tumor significantly associated with high T stage and high pathological stage (P = 0.009, 0.007, respectively). In Kaplan-Meier analysis, patients with higher FD tumors (FD > 0.9746) showed a significantly worse DSS (P = 0.009, log rank). Multivariate analysis demonstrated that tumor FD, T stage, and N stage were independent prognostic factors for DSS. In subset analysis of lymph-node positive gastric cancers, only tumor FD was an independent prognostic factor for DSS. CONCLUSION: CT fractal analysis can be a useful biomarker for gastric cancer patients, reflecting survival and clinicopathologic features.

[Successful Endoscopic Submucosal Dissection of Early Gastric Cancer after Ulcer Healing Associated with a Malignant Cycle-A Case Report].

A 79-year-old man was detected with anemia on medical examination and underwent gastroscopy at the previous hospital. Gastroscopy revealed a 15-mm ulcerative lesion(Type 0-Ⅱc plus Ⅲ)on the greater curvature of the upper gastric body. Tumor biopsy showed well-differentiated adenocarcinoma. The patient was suspected of deep submucosal invasion due to poor stretching of the gastric wall and the ulcer depth; hence, he was transferred to our hospital for surgery. When gastroscopy was repeated, the ulcer was found to be scarred(Type 0-Ⅱc), thereby indicating the occurrence of intramucosal carcinoma; hence, endoscopic submucosal dissection was performed. The pathological finding showed 10×6 mm, tub1, pT1a, ly0, v0, pUL1, pHM0, pVM0, suggesting a curative resection. Early gastric cancer of the depressed type is known to develop a malignant cycle with repeated improvements and exacerbations of the ulcer. Diagnosing the depth of tumor invasion is particularly difficult when there is an active ulcer. For small lesions with active ulcers, repeating gastroscopy might allow for correct diagnosis and appropriate treatment.

Does thoracoscopic esophagectomy really reduce post-operative pneumonia in all cases?

It has been said that "thoracoscopy suppresses the occurrence of pneumonia in comparison to thoracotomy", but does it reflect real clinical practice? To resolve this clinical question, we compared the results of randomized controlled trials (RCTs) and retrospective cohort studies from limited institutes (CLIs) in which a large number of high-volume centers were the main participants to those of retrospective cohort studies based on nationwide databases (CNDs) in which both high-volume centers and low-volume hospitals participated. A systematic review and meta-analysis were conducted to compare the short-term outcomes of thoracoscopic to open esophagectomy for esophageal cancer in the three above-mentioned research formats. In total, 43 studies with 21,057 patients, which included 1 RCT with 115 patients, 38 CLIs with 6,126 patients and 4 CNDs with 14,816 patients, were selected. Pneumonia was one of the most important complications. Although significant superiority in thoracoscopic esophagectomy was observed in RCTs (p = 0.005) and CLIs (p = 0.003), no such difference was seen in findings using nationwide databases (p = 0.69). In conclusion, unlike RCTs and CLIs, CNDs did not show the superiority of thoracoscopic surgery in terms of post-operative pneumonia. RCTs and CLIs were predominantly performed by high-volume hospitals, while CNDs were often performed by low-volume hospitals. In actual clinical practice including various types of hospitals, the superiority of thoracoscopic over open esophagectomy regarding the incidence of pneumonia may, therefore, decrease.

Tumor-derived exosomes influence the cell cycle and cell migration of human esophageal cancer cell lines.

Our laboratory previously reported the usefulness as biomarkers of exosomes in the plasma of esophageal squamous cell carcinoma (ESCC) patients. However, the influence of tumor-derived exosomes on the tumor itself and underlying mechanisms remain unclear. We here report changes in the phenotype and gene expression when cancer cells exist in an environment with tumor-derived exosomes. The exosomes were isolated from the culture medium of human ESCC cells (TE2, T.Tn) by ultracentrifugation; cell proliferation assay, wound-healing assay, and fluorescence imaging of the cell cycle were performed to clarify the phenotypic changes in the high concentration of tumor-derived exosomes. Gene expression changes were also assessed by mRNA microarray, and the data were analyzed by gene set enrichment analysis (GSEA). The data revealed that the proliferation of both TE2 and T.Tn was inhibited, and cell migration ability was upregulated in the exosome exposure group (P < .05). Fluorescence imaging using a fluorescent ubiquitination-based cell cycle indicator expressing ESCC cells revealed that the ratio of G1-phase cells was significantly increased in the exosome exposure group (P < .05). Findings of the GSEA clarified that high-density exposure of cancer-derived exosomes to their parent cancer cells downregulated the expression of genes related to cell proliferation and cell cycle, and upregulated the expression of genes related to actin filament length and extracellular structure organization. In conclusion, an environment of high-density tumor-derived exosomes induces changes in the gene expression and phenotype of tumor cells and may lead to tumor progression or malignant transformation.

Anti-FIRΔexon2, a splicing variant form of PUF60, autoantibody is detected in the sera of esophageal squamous cell carcinoma.

Anti-PUF60 autoantibodies are reportedly detected in the sera of patients with dermatomyositis and Sjögren's syndrome; however, little is known regarding its existence in the sera of cancer patients. FIR, a splicing variant of the PUF60 gene, is a transcriptional repressor of c-myc. In colorectal cancer, there is an overexpression of the dominant negative form of FIR, in which exon 2 is lacking (FIRΔexon2). Previously, large-scale SEREX (serological identification of antigens by recombinant cDNA expression cloning) screenings have identified anti-FIR autoantibodies in the sera of cancer patients. In the present study, we revealed the presence and significance of anti-FIR (FIR/FIRΔexon2) Abs in the sera of patients with esophageal squamous cell carcinoma (ESCC). Our results were validated by an amplified luminescence proximity homogeneous assay using sera of patients with various cancer types. We revealed that anti-FIRΔexon2 Ab had higher sensitivity than anti-FIR Ab. Receiver operating characteristic (ROC) analysis was applied for evaluating the use of anti-FIRΔexon2 Ab as candidate markers such as anti-p53 Ab and carcinoembryonic antigen, and the highest area under the ROC curve was observed in the combination of anti-FIRΔexon2 Ab and anti-p53 Ab. In summary, our results suggest the use of anti-FIRΔexon2 Ab in combination with the anti-p53 Ab as a predictive marker for ESCC. The area under the ROC curve was further increased in the advanced stage of ESCC. The value of anti-FIRΔexon2 autoantibody as novel clinical indicator against ESCC and as a companion diagnostic tool is discussed.

Survival Benefit of Neoadjuvant Chemotherapy with S-1 Plus Docetaxel for Locally Advanced Gastric Cancer: A Propensity Score-Matched Analysis.

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.

Pharmacokinetics of cisplatin in an esophageal cancer patient on hemodialysis who was treated with a full-dose cisplatin-fluorouracil regimen: A case report.

INTRODUCTION: Cancer patients undergoing hemodialysis might be under-treated because the pharmacokinetics of anti-cancer drugs in such patients remain unknown and out of concern related to the potential development of severe adverse effects. However, patients with chemosensitive cancer, such as esophageal cancer, should receive chemotherapy at a dose that is sufficient to attain a favorable therapeutic effect. We herein present an interesting case involving an esophageal cancer patient who was successfully treated with subtotal thoracic esophagectomy, and adjuvant full-dose chemotherapy with cisplatin and 5-fluorouracil while concomitantly undergoing hemodialysis. We carried out a pharmacokinetics analysis of cisplatin, and also conducted a systematic review on the dose and pharmacokinetics. CASE REPORT: A 57-year-old male patient with esophageal cancer who was undergoing hemodialysis was referred to our hospital. He underwent subtotal thoracic esophagectomy. The pathological diagnosis was T1b, N2 (5/26), M0, ly2, v2, stage IIIA (Union for International Cancer Control, 8th edition). Because of the high degree of lymph node metastasis, adjuvant chemotherapy with cisplatin was recommended. Cisplatin (80 mg/m2) was infused intravenously within 30 min on day 1, and 5-fluorouracil (800 mg/m2) was infused continuously on days 1-5 of a 28-day cycle. Thrombocytopenia (grade 3) occurred on day 16, leucopenia (grade 3) occurred on day 23, and anemia (grade 3) occurred on day 30. The onset of hematologic toxicities was prolonged in comparison to patients with a normal renal function.

[Successful Treatment of Gastric Cancer with Conversion Surgery after Nivolumab Treatment-A Case Report].

Immunocheckpoint inhibitors including anti-PD-1 antibody have shown certain therapeutic effects on various cancer types. They have also attracted great attention as novel cancer treatment options in addition to surgical resection, chemotherapy, and radiation therapy. Herein, we report a case of gastric cancer that was successfully treated with conversion surgery after nivolumab treatment. The patient was 68 years old and male. Upper gastrointestinal endoscopy revealed a type 3 tumor in the antrum, and he was referred to our department for further examination. The gastric cancer was diagnosed as cT4aN2M0, cStage ⅢA, and he was administered SOX as the first-line and nab-PTX/RAM as the second-line treatment, which was also a PD. As the third-line treatment, nivolumab showed remarkable reduction of the tumor after initiation, and after 14 courses, conversion surgery was performed. The patient remains alive without recurrence.

[Development of TP53-Targeted Treatment in Esophageal Squamous Cell Carcinoma Using Cancer Genomic Profiling Test].

Recently, the interest in cancer genomic medicine has increased, owing to the powerful and cost-effective technology of next-generation sequencing(NGS), which allows rapid identification of a large number of gene mutations. TP53 mutations are frequently found in solid cancers, especially in esophageal squamous cell carcinoma(ESCC), wherein the frequency of TP53 mutation is considered to be 90% or more. However, there is no clinical targeted therapy as yet utilizing TP53. Here, we aimed to characterize TP53 mutations associated with ESCC, in order to assess its feasibility as a therapeutic target. We extracted DNA and RNA from specimens of ESCC patients and analyzed them using NGS, which revealed different TP53 mutations. Based on previous reports, it is considered that different TP53 mutations lead to different functions of the protein, and subsequently account for varied prognosis in squamous cell carcinoma of the head and neck. We also performed cell viability assay using ESCC cell lines with different TP53 mutations and 2 kinds of p53-targeted drug and found differences in the growth inhibition of the cell lines. Although individual treatment can be determined depending on the type of TP53 mutation, it would be necessary to further examine the interaction of TP53 with other genes to determine its therapeutic efficacy as a target.

Antitumor effects of metformin are a result of inhibiting nuclear factor kappa B nuclear translocation in esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is an intractable digestive organ cancer that has proven difficult to treat despite multidisciplinary therapy, and a new treatment strategy is demanded. Metformin is used for type 2 diabetes mellitus and its antitumor effects have been reported recently. Metformin exerts antitumor effects in various respects, such as inhibiting inflammation, tumor growth and epithelial-mesenchymal transition (EMT). However, few reports have described the efficacy of metformin on ESCC, and their findings have been controversial. We analyzed the antitumor effects of metformin and clarified its effects on anti-inflammation, growth suppression and EMT inhibition. Activation of nuclear factor kappa B (NF-κB), the major transcription factor induced by inflammation, was investigated by immunostaining. We found that localization of NF-κB in the nucleus was reduced after metformin treatment. This suggests that metformin inhibited the activation of NF-κB. Metformin inhibited tumor growth and induced apoptosis in ESCC cell lines. Associated with EMT, we examined cell motility by a wound healing assay and the epithelial marker E-cadherin expression of various ESCC cell lines by western blotting. Metformin inhibited cell motility and induced E-cadherin expression. In conclusion, metformin showed multiple antitumor effects such as growth suppression, invasion inhibition, and control of EMT by inhibiting NF-κB localization on ESCC. Further exploration of the marker of treatment efficacy and combination therapy could result in the possibility for novel treatment to use metformin on ESCC.

ZNF750 Expression Is a Potential Prognostic Biomarker in Esophageal Squamous Cell Carcinoma.

OBJECTIVE: ZNF750, a transcriptional regulator of epidermal differentiation, has been identified as a tumor suppressor in esophageal squamous cell carcinoma (ESCC). The aim of the present study was to investigate the clinical and prognostic significance of ZNF750 expression and to evaluate the effect of ZNF750 knockdown on cell proliferation, migration, and invasion in ESCC. METHODS: A total of 124 patients with ESCC who underwent curative esophagectomy were evaluated in this study. The expression of ZNF750 in surgical specimens was immunohistochemically assessed and used in the analysis of clinicopathological features and overall survival (OS). The molecular role of ZNF750 was investigated by ZNF750 knockdown using small interfering RNA (siRNA) in ESCC cell lines. RESULTS: Low ZNF750 expression had a significant correlation with positive lymph node metastasis (p = 0.028). Furthermore, there was a significant relationship between low expression of ZNF750 in ESCC and a poor OS, and a multivariate analysis showed that low ZNF750 expression was an independent prognostic factor (p = 0.020). The cell growth, migration, and invasion were significantly increased by downregulation of ZNF750. CONCLUSIONS: The low expression of ZNF750 was significantly associated with a poor prognosis, and ZNF750 expression may, therefore, be a reliable prognostic biomarker in ESCC.