Fibroblast activation protein-targeted near-infrared photoimmunotherapy depletes immunosuppressive cancer-associated fibroblasts and remodels local tumor immunity.

BACKGROUND: Cancer-associated fibroblasts (CAFs) in the tumor microenvironment (TME) play a critical role in tumor immunosuppression. However, targeted depletion of CAFs is difficult due to their diverse cells of origin and the resulting lack of specific surface markers. Near-infrared photoimmunotherapy (NIR-PIT) is a novel cancer treatment that leads to rapid cell membrane damage. METHODS: In this study, we used anti-mouse fibroblast activation protein (FAP) antibody to target FAP+ CAFs (FAP-targeted NIR-PIT) and investigated whether this therapy could suppress tumor progression and improve tumor immunity. RESULTS: FAP-targeted NIR-PIT induced specific cell death in CAFs without damaging adjacent normal cells. Furthermore, FAP-targeted NIR-PIT treated mice showed significant tumor regression in the CAF-rich tumor model accompanied by an increase in CD8+ tumor infiltrating lymphocytes (TILs). Moreover, treated tumors showed increased levels of IFN-γ, TNF-α, and IL-2 in CD8+ TILs compared with non-treated tumors, suggesting enhanced antitumor immunity. CONCLUSIONS: Cancers with FAP-positive CAFs in their TME grow rapidly and FAP-targeted NIR-PIT not only suppresses their growth but improves tumor immunosuppression. Thus, FAP-targeted NIR-PIT is a potential therapeutic strategy for selectively targeting the TME of CAF+ tumors.

Recurrence-free survival as a surrogate endpoint for overall survival after neoadjuvant chemotherapy and surgery for oesophageal squamous cell carcinoma.

BACKGROUND: Overall survival is considered as one of the most important endpoints of treatment efficacy but often requires long follow-up. This study aimed to determine the validity of recurrence-free survival as a surrogate endpoint for overall survival in patients with surgically resectable advanced oesophageal squamous cell carcinoma (OSCC). METHODS: Patients with OSCC who received neoadjuvant cisplatin and 5-fluorouracil, or docetaxel, cisplatin and 5-fluorouracil, at 58 Japanese oesophageal centres certified by the Japan Esophageal Society were reviewed retrospectively. The correlation between recurrence-free and overall survival was assessed using Kendall's τ. RESULTS: The study included 3154 patients. The 5-year overall and recurrence-free survival rates were 56.6 and 47.7% respectively. The primary analysis revealed a strong correlation between recurrence-free and overall survival (Kendall's τ 0.797, 95% c.i. 0.782 to 0.812) at the individual level. Subgroup analysis showed a positive relationship between a more favourable pathological response to neoadjuvant chemotherapy and a higher τ value. In the meta-regression model, the adjusted R2 value at the institutional level was 100 (95% c.i. 40.2 to 100)%. The surrogate threshold effect was 0.703. CONCLUSION: There was a strong correlation between recurrence-free and overall survival in patients with surgically resectable OSCC who underwent neoadjuvant chemotherapy, and this was more pronounced in patients with a better response to neoadjuvant chemotherapy.

Perioperative and Postoperative Continuous Nutritional Counseling Improves Quality of Life of Gastric Cancer Patient Undergoing Gastrectomy.

Post-gastrectomy syndrome (PGS) and body weight loss (BWL) decrease quality of life (QOL) and survival of the patient undergoing gastrectomy. We have introduced perioperative and post-discharge continuous nutritional counseling (CNC) to prevent BWL and improve QOL after gastrectomy. In the present study, we evaluated the effect of CNC on QOL using the Post-gastrectomy Syndrome Assessment Scale-45 (PGSAS-45). Eighty-three patients with gastric cancer (GC) who underwent curative gastrectomy between March 2018 and July 2019 were retrospectively analyzed. Patients received either pre-discharge nutritional counseling alone (control group, n = 45) or CNC (CNC group, n = 38) after gastrectomy. QOL at 12 months after gastrectomy was compared between the two groups. In QOL assessment, change in body weight (-7.98% vs. -12.77%, p = 0.0057), ingested amount of food per meal (7.00 vs. 6.07, p = 0.042) and ability for working (1.89 vs. 2.36, p = 0.049) were significantly better in CNC group than control group. Multiple regression analysis showed that CNC was a significantly beneficial factor for abdominal pain subscale (p = 0.028), diarrhea subscale (p = 0.047), ingested amount of food per meal (p = 0.012), Ability for working (p = 0.031) and dissatisfaction at the meal (p = 0.047). Perioperative and postoperative CNC could improve QOL in the patient undergoing gastrectomy in addition to preventing postoperative BWL.

Effectiveness of prehabilitation during neoadjuvant therapy for patients with esophageal or gastroesophageal junction cancer: a systematic review.

Progression of the physical weakness during neoadjuvant therapy (NAT) in patients with esophageal or gastroesophageal junction cancer is a serious problem; however, prehabilitation during NAT has the potential to overcome the unmet need. Nevertheless, systematic reviews on this topic have not been summarized. Therefore, this systematic review aimed to determine prehabilitation's effectiveness, acceptability, and safety during NAT for patients with esophageal or gastroesophageal junction cancer. An electronic search was performed in the MEDLINE, Web of Science, CENTRAL, CINAHL, and PEDro databases. A meta-analysis was conducted to assess the effectiveness of prehabilitation during NAT, along with a descriptive analysis of acceptance and safety. This study analyzed data from three randomized controlled trials (RCTs) and nine non-RCTs involving 664 patients. The meta-analysis of two RCTs demonstrated that prehabilitation during NAT may be more effective than usual care in enhancing tolerance to NAT and grip strength; moreover, one RCT and three non-RCTs revealed that prehabilitation may reduce the risk of postoperative complications. The adherence rates for exercise programs in two RCTs and seven non-RCTs were 55-76%. Additionally, two studies reported a 76% adherence rate for multimodal prehabilitation programs, including exercise, dietary, and psychological care. Six studies reported no serious prehabilitation-related adverse events during NAT. Prehabilitation during NAT may be a safe and beneficial intervention strategy for patients with esophageal or gastroesophageal junction cancer. However, the investigation of strategies to enhance adherence is essential. Furthermore, additional high-quality RCTs are needed to examine the effect of prehabilitation during NAT.

Comparison of proton-based definitive chemoradiotherapy and surgery-based therapy for esophageals cell carcinoma: a multi-center retrospective Japanese cohort study.

BACKGROUND: Proton-based, definitive chemoradiotherapy (P-CRT) for esophageal squamous cell carcinoma (ESCC) previously showed comparable survival outcomes with the surgery-based therapy, i.e., neoadjuvant chemotherapy followed by esophagectomy (NAC-S), in a single-institutional study. This study aimed to validate this message in a Japanese multicenter study. METHODS: Eleven Japanese esophageal cancer specialty hospitals have participated. A total of 518 cases with clinical Stage I-IVA ESCC between 2010 and 2019, including 168 P-CRT and 350 NAC-S patients, were enrolled and long-term outcomes were evaluated. Propensity-score weighting analyses with overlap weighting for confounding adjustment were used. RESULTS: The 3-year overall survival (OS) of the P-CRT group was equivalent to the NAC-S group (74.8% vs. 72.7%, hazard ratio [HR]: 0.87, 95% confidence interval [CI]: 0.61-1.25). Although, the 3-year P-CRT group progression-free survival (PFS) was inferior to the NAC-S group (51.4% vs. 59.6%, HR 1.39, 95% CI 1.04-1.85), the progression P-CRT group cases showed better survival than the NAC-S group (HR 0.58, 95% CI 0.38-0.88), largely because of salvage surgery or endoscopic submucosal dissection for local progression. The survival advantage of P-CRT over NAC-S was more pronounced in the cT1-2 (HR 0.61, 95% CI 0.29-1.26) and cStage I-II (HR 0.50, 95% CI 0.24-1.07) subgroups, although this trend was not evident in other populations, such as cT3-4 and cStage III-IVA. CONCLUSIONS: Proton-based CRT for ESCC showed equivalent OS to surgery-based therapy. Especially for patients with cT1-2 and cStage I-II disease, proton-based CRT has the potential to serve as a first-line treatment.

Oncolytic virus-mediated reducing of myeloid-derived suppressor cells enhances the efficacy of PD-L1 blockade in gemcitabine-resistant pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is often refractory to treatment with gemcitabine (GEM) and immune checkpoint inhibitors including anti-programmed cell death ligand 1 (PD-L1) antibody. However, the precise relationship between GEM-resistant PDAC and development of an immunosuppressive tumor microenvironment (TME) remains unclear. In this study, we investigated the immunosuppressive TME in parental and GEM-resistant PDAC tumors and assessed the therapeutic potential of combination therapy with the telomerase-specific replication-competent oncolytic adenovirus OBP-702, which induces tumor suppressor p53 protein and PD-L1 blockade against GEM-resistant PDAC tumors. Mouse PDAC cells (PAN02) and human PDAC cells (MIA PaCa-2, BxPC-3) were used to establish GEM-resistant PDAC lines. PD-L1 expression and the immunosuppressive TME were analyzed using parental and GEM-resistant PDAC cells. A cytokine array was used to investigate the underlying mechanism of immunosuppressive TME induction by GEM-resistant PAN02 cells. The GEM-resistant PAN02 tumor model was used to evaluate the antitumor effect of combination therapy with OBP-702 and PD-L1 blockade. GEM-resistant PDAC cells exhibited higher PD-L1 expression and produced higher granulocyte-macrophage colony-stimulating factor (GM-CSF) levels compared with parental cells, inducing an immunosuppressive TME and the accumulation of myeloid-derived suppressor cells (MDSCs). OBP-702 significantly inhibited GEM-resistant PAN02 tumor growth by suppressing GM-CSF-mediated MDSC accumulation. Moreover, combination treatment with OBP-702 significantly enhanced the antitumor efficacy of PD-L1 blockade against GEM-resistant PAN02 tumors. The present results suggest that combination therapy involving OBP-702 and PD-L1 blockade is a promising antitumor strategy for treating GEM-resistant PDAC with GM-CSF-induced immunosuppressive TME formation.

Overcoming cancer-associated fibroblast-induced immunosuppression by anti-interleukin-6 receptor antibody.

Cancer-associated fibroblasts (CAFs) are a critical component of the tumor microenvironment and play a central role in tumor progression. Previously, we reported that CAFs might induce tumor immunosuppression via interleukin-6 (IL-6) and promote tumor progression by blocking local IL-6 in the tumor microenvironment with neutralizing antibody. Here, we explore whether an anti-IL-6 receptor antibody could be used as systemic therapy to treat cancer, and further investigate the mechanisms by which IL-6 induces tumor immunosuppression. In clinical samples, IL-6 expression was significantly correlated with α-smooth muscle actin expression, and high IL-6 cases showed tumor immunosuppression. Multivariate analysis showed that IL-6 expression was an independent prognostic factor. In vitro, IL-6 contributed to cell proliferation and differentiation into CAFs. Moreover, IL-6 increased hypoxia-inducible factor 1α (HIF1α) expression and induced tumor immunosuppression by enhancing glucose uptake by cancer cells and competing for glucose with immune cells. MR16-1, a rodent analog of anti-IL-6 receptor antibody, overcame CAF-induced immunosuppression and suppressed tumor progression in immunocompetent murine cancer models by regulating HIF1α activation in vivo. The anti-IL-6 receptor antibody could be systemically employed to overcome tumor immunosuppression and improve patient survival with various cancers. Furthermore, the tumor immunosuppression was suggested to be induced by IL-6 via HIF1α activation.

PD-L1-expressing cancer-associated fibroblasts induce tumor immunosuppression and contribute to poor clinical outcome in esophageal cancer.

The programmed cell death 1 protein (PD-1)/programmed cell death ligand 1 (PD-L1) axis plays a crucial role in tumor immunosuppression, while the cancer-associated fibroblasts (CAFs) have various tumor-promoting functions. To determine the advantage of immunotherapy, the relationship between the cancer cells and the CAFs was evaluated in terms of the PD-1/PD-L1 axis. Overall, 140 cases of esophageal cancer underwent an immunohistochemical analysis of the PD-L1 expression and its association with the expression of the α smooth muscle actin, fibroblast activation protein, CD8, and forkhead box P3 (FoxP3) positive cells. The relationship between the cancer cells and the CAFs was evaluated in vitro, and the effect of the anti-PD-L1 antibody was evaluated using a syngeneic mouse model. A survival analysis showed that the PD-L1+ CAF group had worse survival than the PD-L1- group. In vitro and in vivo, direct interaction between the cancer cells and the CAFs showed a mutually upregulated PD-L1 expression. In vivo, the anti-PD-L1 antibody increased the number of dead CAFs and cancer cells, resulting in increased CD8+ T cells and decreased FoxP3+ regulatory T cells. We demonstrated that the PD-L1-expressing CAFs lead to poor outcomes in patients with esophageal cancer. The cancer cells and the CAFs mutually enhanced the PD-L1 expression and induced tumor immunosuppression. Therefore, the PD-L1-expressing CAFs may be good targets for cancer therapy, inhibiting tumor progression and improving host tumor immunity.

Effect of Patient-Participation Continuous Nutritional Counseling in Gastric Cancer Patients who Underwent Gastrectomy.

BACKGROUND: Body weight loss (BWL) and skeletal muscle loss (SML) are inevitable after gastrectomy for gastric cancer (GC) and can decrease patients' quality of life (QOL) and survival. OBJECTIVE: The aim of this retrospective study was to evaluate the effect of perioperative and post-discharge patient participation in continuous nutritional counseling (CNC) on post-gastrectomy BWL and SML. METHODS: Ninety-three patients with GC who underwent curative gastrectomy between March 2018 and July 2019 were analyzed. Patients received either pre-discharge nutritional counseling alone (control group, n = 49) or patient-participation CNC (CNC group, n = 44) after gastrectomy. Differences between percentage BWL (%BWL), percentage SML (%SML), and nutrition-related blood parameters between the preoperative values and those at 12 months after surgery were compared between the groups. RESULTS: Compared with the control group, %BWL was significantly lower in the CNC group at 1 month (-6.2 ± 2.5% vs. -7.9 ± 3.3%, p = 0.005), 6 months (-7.8 ± 6.6% vs. -12.3 ± 6.4%, p = 0.001) and 12 months (-7.9 ± 7.6% vs. -13.2 ± 8.2%, p = 0.002), and %SML was significantly lower in the CNC group at 12 months (-5.3 ± 10.3% vs. -12.8 ± 12%, p = 0.002). Regarding nutrition-related blood parameters, change in total cholesterol was significantly lower in the CNC group than the control group at 12 months after surgery (p = 0.02). Multivariate analysis identified no CNC as an independent risk factor for severe BWL (p = 0.001) and SML (p = 0.006) at 12 months after surgery. CONCLUSIONS: Following gastrectomy, patient-participation CNC prevented postoperative BWL and SML after surgery. These results support the induction of such a CNC program in these patients.

Validity of the 30-Second Chair-Stand Test to Assess Exercise Tolerance and Clinical Outcomes in Patients with Esophageal Cancer: A Retrospective Study with Reference to 6-Minute Walk Test Results.

This retrospective study aimed to investigate the validity of a 30-sec chair stand test (CS-30) as a simple test to assess exercise tolerance and clinical outcomes in 53 Japanese patients with esophageal cancer. There was a strong correlation between the results of CS-30 and the 6-min walk test (6MWT), the gold standard for assessing exercise tolerance (r=0.759). Furthermore, fewer patients whose CS-30 score was greater than 16 (the cutoff value defined based on 6MWT) experienced pneumonia in their postoperative course. These results suggest that exercise tolerance could be assessed using CS-30, and its cutoff value may be useful in predicting postoperative pneumonia risk.

Stroke volume variation and dynamic arterial elastance predict fluid responsiveness even in thoracoscopic esophagectomy: a prospective observational study.

PURPOSE: It remains unknown whether stroke volume variation (SVV), pulse pressure variation (PPV), and dynamic arterial elastance (Eadyn) are suitable for monitoring fluid management during thoracoscopic esophagectomy (TE) in the prone position with one-lung ventilation and artificial pneumothorax. Our study aimed to evaluate the accuracy of SVV, PVV, and Eadyn in predicting the fluid responsiveness in these patients. METHODS: We recruited 24 patients who had undergone TE. Patients with a mean arterial blood pressure ≤ 65 mmHg received a 200-ml bolus of 6% hydroxyethyl starch over 10 min. Fluid responders showed the stroke volume index ≥ 15% 5 min after the fluid bolus. Receiver operating characteristic (ROC) curves were generated and area under the ROC curve (AUROC) was calculated. RESULTS: We obtained 61 fluid bolus data points, of which 20 were responders and 41 were non-responders. The median SVV before the fluid bolus in responders was significantly higher than that in non-responders (18% [interquartile range (IQR) 13-21] vs. 12% [IQR 8-15], P = 0.001). Eadyn was significantly lower in responders than in non-responders (0.55 [IQR 0.45-0.78] vs. 0.91 [IQR 0.67-1.00], P < 0.001). There was no difference in the PPV between the groups. The AUROC was 0.76 for SVV (95% confidence interval [CI] 0.62-0.89, P = 0.001), 0.56 for PPV (95% CI 0.41-0.71, P = 0.44), and 0.82 for Eadyn (95% CI 0.69-0.95, P < 0.001). CONCLUSIONS: SVV and Eadyn are reliable parameters for predicting fluid responsiveness in patients undergoing TE.

[Novel Therapy Targeting the Cancer Microenvironment Using Near-Infrared Photoimmunotherapy Leading to Tumor Immune Activation].

Near-infrared photoimmunotherapy(NIR-PIT)is a novel cancer treatment modality that employs antibody-IRDye700DX (IR700)conjugates. Recently, the clinical application of NIR-PIT has received approval in Japan for patients with inoperable head and neck cancer, specifically targeting the human epidermal growth factor receptor(hEGFR). Furthermore, NIR-PIT extends beyond the scope of tumor antigens and can be employed to eliminate specific host cells that contribute to the creation of immune-permissive environments supporting tumor growth. One of the distinguishing features of NIR-PIT is its ability to selectively eliminate various cell types within the tumor microenvironment(TME)by specifically targeting distinct antigens. By employing podoplanin(PDPN)-targeted NIR-PIT, PDPN-expressing fibroblasts were selectively eradicated, resulting in the suppression of tumor progression and a notable extension of overall survival. Additionally, we investigated the efficacy of depleting myeloid-derived suppressor cells(MDSCs)using NIR-PIT. This approach led to the selective elimination of MDSCs within tumors, and remarkable abscopal effects were observed in bilateral tumor models. Hence, NIR-PIT holds immense promise for the treatment of diverse cancer types by precisely targeting tumor cells, fibroblasts, and immune cells.

[Therapeutic Effect of Oncolytic Adenovirus on Pancreatic Cancer Stroma].

Pancreatic ductal adenocarcinoma(PDAC)is lethal malignancy with abundant stroma. Cancer-associated fibroblasts (CAFs) exist in the PDAC stroma and contribute to progression of malignant transformation, treatment resistance, and recurrence. However, effective treatment to control PDAC stroma has not been established. We have developed tumor suppressor gene p53-armed oncolytic adenovirus(OBP-702), and have clarified therapeutic effects on PDAC cells. In this study, we investigate the therapeutic effect of OBP-702 on PDAC CAF.

Outcomes of solitary postoperative recurrence of esophageal squamous cell carcinoma diagnosed with FDG-PET/CT and treated with definitive radiation therapy.

BACKGROUND: Surgical resection of esophageal cancer is frequently performed to achieve a complete cure. However, the postoperative recurrence rate is 36.8-42.5%, leading to poor prognosis. Radiation therapy has been used to treat recurrences; solitary recurrence has been proposed as a prognostic factor for radiation therapy, though its significance is unclear. 18F-fluorodeoxyglucose positron emission tomography is a highly accurate diagnostic modality for esophageal cancer. This retrospective study aimed to analyze the outcomes of solitary postoperative recurrences of esophageal squamous cell carcinoma diagnosed with 18F-fluorodeoxyglucose positron emission tomography and treated with definitive radiation therapy. METHODS: We examined 27 patients who underwent definitive radiation therapy for single or multiple postoperative recurrences of esophageal squamous cell carcinoma between May 2015 and April 2021. 18F-fluorodeoxyglucose positron emission tomography/computed tomography was performed within 3 months before the commencement of radiation therapy. Kaplan-Meier, univariate, and multivariate analyses were performed to examine the overall survival and identify potential prognostic factors. RESULTS: The 1-, 2-, and 3-year overall survival rates were 85.2%, 62.6%, and 47.3%, respectively, and solitary recurrence was the only significant factor associated with overall survival (P = 0.003). The 1-, 2-, and 3-year overall survival rates in patients with solitary recurrence were 91.7%, 80.2%, and 80.2%, respectively, and in patients with multiple recurrences they were 80.0%, 50.3%, and 25.1%, respectively. Multivariate analysis also showed solitary recurrence as a significant factor for overall survival. CONCLUSIONS: When diagnosed with 18F-fluorodeoxyglucose positron emission tomography/computed tomography, solitary recurrence appears to have a more favorable prognosis than multiple recurrences.

Tumor-targeted fluorescence labeling systems for cancer diagnosis and treatment.

Conventional imaging techniques are available for clinical identification of tumor sites. However, detecting metastatic tumor cells that are spreading from primary tumor sites using conventional imaging techniques remains difficult. In contrast, fluorescence-based labeling systems are useful tools for detecting tumor cells at the single-cell level in cancer research. The ability to detect fluorescent-labeled tumor cells enables investigations of the biodistribution of tumor cells for the diagnosis and treatment of cancer. For example, the presence of fluorescent tumor cells in the peripheral blood of cancer patients is a predictive biomarker for early diagnosis of distant metastasis. The elimination of fluorescent tumor cells without damaging normal tissues is ideal for minimally invasive treatment of cancer. To capture fluorescent tumor cells within normal tissues, however, tumor-specific activated target molecules are needed. This review focuses on recent advances in tumor-targeted fluorescence labeling systems, in which indirect reporter labeling using tumor-specific promoters is applied to fluorescence labeling of tumor cells for the diagnosis and treatment of cancer. Telomerase promoter-dependent fluorescence labeling using replication-competent viral vectors produces fluorescent proteins that can be used to detect and eliminate telomerase-positive tumor cells. Tissue-specific promoter-dependent fluorescence labeling enables identification of specific tumor cells. Vimentin promoter-dependent fluorescence labeling is a useful tool for identifying tumor cells that undergo epithelial-mesenchymal transition (EMT). The evaluation of tumor cells undergoing EMT is important for accurately assessing metastatic potential. Thus, tumor-targeted fluorescence labeling systems represent novel platforms that enable the capture of tumor cells for the diagnosis and treatment of cancer.

Surgical technique of suprapancreatic D2 lymphadenectomy focusing on the posterior hepatic plexus for advanced gastric cancer.

PURPOSE: Although D2 lymphadenectomy is currently considered a standard procedure for advanced gastric cancer (GC) worldwide, there is room for discussion about the appropriate range of suprapancreatic D2 lymphadenectomy. Focusing on the posterior hepatic plexus (PHP), which is not well recognized, we developed a surgical technique of suprapancreatic D2 lymphadenectomy, which we have called PHP-D2, and its short-term and long-term efficacies were evaluated in comparison with non-PHP-D2. METHODS: GC patients who underwent distal gastrectomy with D2 lymphadenectomy between July 2006 and May 2013 were enrolled, from which patients who had peritoneal metastasis and/or were peritoneal cytology-positive during surgery were excluded. Their medical records were retrospectively reviewed. RESULTS: Ninety-two patients (non-PHP-D2: 48, PHP-D2: 44) were enrolled. Shorter operation time (330 min vs 275 min, p < 0.0001) and less blood loss (290 mL vs 125 mL, p < 0.0001) were observed in PHP-D2, and no pancreatic fistulas were observed in PHP-D2. More lymph nodes of #11p (1 vs 1.5, p = 0.0328) and #12a lymph nodes (0 vs 1, p = 0.0034) were retrieved in PHP-D2, with no significant differences in #8a and #9 lymph nodes. Lymphatic recurrence was significantly less in PHP-D2 (p = 0.0166), and univariate and multivariate analyses showed that non-PHP-D2 was a significant risk factor for lymphatic recurrence (p = 0.0158), although there were no significant differences between non-PHP-D2 and PHP-D2 in 5-year overall survival and 5-year relapse-free survival. CONCLUSION: PHP-D2 was a safe and feasible procedure that had the potential to reduce lymphatic recurrence, and it can be a standard procedure of D2 lymphadenectomy for advanced GC.

Overexpression of Adenovirus E1A Reverses Transforming Growth Factor-ß-induced Epithelial-mesenchymal Transition in Human Esophageal Cancer Cells.

The epithelial-mesenchymal transition (EMT), a normal biological process by which epithelial cells acquire a mesenchymal phenotype, is associated with migration, metastasis, and chemoresistance in cancer cells, and with poor prognosis in patients with esophageal cancer. However, therapeutic strategies to inhibit EMT in tumor environments remain elusive. Here, we show the therapeutic potential of telomerase-specific replication- competent oncolytic adenovirus OBP-301 in human esophageal cancer TE4 and TE6 cells with an EMT phenotype. Transforming growth factor-ß (TGF-ß) administration induced the EMT phenotype with spindleshaped morphology, upregulation of mesenchymal markers and EMT transcription factors, migration, and chemoresistance in TE4 and TE6 cells. OBP-301 significantly inhibited the EMT phenotype via E1 accumulation. EMT cancer cells were susceptible to OBP-301 via massive autophagy induction. OBP-301 suppressed tumor growth and lymph node metastasis of TE4 cells co-inoculated with TGF-ß-secreting fibroblasts. Our results suggest that OBP-301 inhibits the TGF-ß-induced EMT phenotype in human esophageal cancer cells. OBP-301-mediated E1A overexpression is a promising antitumor strategy to inhibit EMT-mediated esophageal cancer progression.

Effectiveness of early exercise on reducing skeletal muscle loss during preoperative neoadjuvant chemotherapy for esophageal cancer.

PURPOSE: To investigate if early exercise can help prevent skeletal muscle loss and improve the clinical outcomes of esophageal cancer patients receiving preoperative neoadjuvant chemotherapy (NAC). METHODS: This was a single-center, retrospective observational cohort study of 110 patients with advanced esophageal cancer. We analyzed the effect of early exercise on the risk of skeletal muscle loss (defined as > 2.98%) during NAC and the subsequent clinical outcomes. Patients in the early exercise group (n = 71) started exercise therapy 8 days earlier than those the late exercise group (n = 39). RESULTS: The median age of the patients was 65.4 years, the mean BMI was 21.1 kg/m2, and 92 (84%) of the 110 patients were men. Skeletal muscle loss occurred in 34% and 67% of the early and late exercise groups, respectively (p < 0.001). There was a lower risk of surgical site infection in the early exercise group (1% vs 16%, p = 0.021). Multivariate analysis revealed that early exercise reduced the risk of skeletal muscle loss (OR = 0.25, 95% CI 0.09-0.65, p = 0.006). CONCLUSIONS: Our results suggest that early exercise reduces the risk of both skeletal muscle loss during NAC and subsequent surgical site infection in patients with esophageal cancer.

Neoadjuvant chemotherapy for locally advanced esophageal cancer comparing cisplatin and 5-fluorouracil versus docetaxel plus cisplatin and 5-fluorouracil: a propensity score matching analysis.

BACKGROUND: The standard treatment for locally advanced esophageal cancer is preoperative chemotherapy with cisplatin and 5-fluorouracil (CF), followed by surgery. Although docetaxel plus cisplatin and 5-fluorouracil (DCF) has been reported to have favorable outcomes, no study has compared its therapeutic efficacy to that of standard treatment. This study aimed to compare the therapeutic effects of CF and DCF in the real world by matching patient background factors using propensity scores. METHODS: We retrospectively reviewed the data of 237 patients with esophageal squamous cell carcinoma who underwent esophagectomy between January 2008 and December 2018. Patients were divided into two groups based on the preoperative chemotherapy regimens of CF (79 patients) or DCF (158 patients), and 49 matched pairs were finally analyzed using propensity score matching. Short- and long-term outcomes were compared between groups. RESULTS: After matching, although no significant differences in survival were observed among the groups, patients receiving DCF showed a significantly high histological response (P < 0.001). Subgroup analyses demonstrated that DCF therapy had better overall survival (P = 0.046) and relapse-free survival (P = 0.010) among pathological T3 and T4 cases. Whereas, adverse effects of chemotherapy were more frequent in the DCF group. CONCLUSIONS: Patients receiving DCF had higher pathological response and better survival than those receiving CF, especially in pathological T3 and T4 cases matched using propensity scores. Thus, the DCF regimen might be an effective treatment for locally advanced esophageal cancer. However, the adverse side effects of chemotherapy remain high and should be handled appropriately.

Nanog is a promising chemoresistant stemness marker and therapeutic target by iron chelators for esophageal cancer.

Esophageal cancer is a disease showing poor prognosis. Although combination chemotherapy using cisplatin (CDDP) and 5-fluorouracil is standard for unresectable esophageal cancer, the response rate is 35%. Cancer stem cells (CSCs) and inflammation are reportedly responsible for the poor prognosis of esophageal cancer. However, comprehensive analyses have not been conducted and proposals for progress remain lacking. Iron is known to be a key factor in the stemness of CSCs. Our study focused on the therapeutic potential of iron control using iron chelators for CSCs in esophageal cancer. Among 134 immunohistochemically analyzed cases, Nanog expression was high in 98 cases and low in 36 cases. High Nanog expression correlated with low overall and disease-free survivals. The iron chelators deferasirox (DFX) and SP10 suppressed the proliferation and expression of stemness markers in TE8 and OE33 cells. DFX and SP10 did not induce compensatory interleukin (IL)-6 secretion, although CDDP did result in high induction. Moreover, BBI608 and SSZ, as other CSC-targeting drugs, could not suppress the expression of stemness markers. Overall, Nanog expression appears related to poor prognosis in esophageal cancer patients, and inhibition of stemness and compensatory IL-6 secretion by iron chelators may offer a novel therapeutic strategy for esophageal cancer.