Distinct functions between ferrous and ferric iron in lung cancer cell growth.

Accumulating evidence suggests an association between iron metabolism and lung cancer progression. In biological systems, iron is present in either reduced (Fe2+ ; ferrous) or oxidized (Fe3+ ; ferric) states. However, ferrous and ferric iron exhibit distinct chemical and biological properties, the role of ferrous and ferric iron in lung cancer cell growth has not been clearly distinguished. In this study, we manipulated the balance between cellular ferrous and ferric iron status by inducing gene mutations involving the FBXL5-IRP2 axis, a ubiquitin-dependent regulatory system for cellular iron homeostasis, and determined its effects on lung cancer cell growth. FBXL5 depletion (ferrous iron accumulation) was found to suppress lung cancer cell growth, whereas IRP2 depletion (ferric iron accumulation) did not suppress such growth, suggesting that ferrous iron but not ferric iron plays a suppressive role in cell growth. Mechanistically, the depletion of FBXL5 impaired the degradation of the cyclin-dependent kinase inhibitor, p27, resulting in a delay in the cell cycle at the G1/S phase. FBXL5 depletion in lung cancer cells also improved the survival of tumor-bearing mice. Overall, this study highlights the important function of ferrous iron in cell cycle progression and lung cancer cell growth.

Dynamic Alteration in HLA-E Expression and Soluble HLA-E via Interaction with Natural Killer Cells in Gastric Cancer.

BACKGROUND: Some reports showed the immune tolerance of soluble human leukocyte antigen E (HLA-E), but the role that soluble HLA-E plays in gastric cancer (GC) is unknown. We aimed to clarify the molecular mechanism and clinical significance of soluble HLA-E in GC. METHODS: We examined the expression of HLA-E on GC cells and soluble HLA-E under co-culture with natural killer (NK) cells in a time-dependent manner. Changes in NK cell activity were investigated using anti-NK group 2 member A (NKG2A) antibodies in the presence of soluble HLA-E. Expression of soluble HLA-E in the serum of GC patients was determined. RESULTS: Whereas HLA-E expression on GC cells peaked with interferon (IFN)-γ secretion by NK cells in a time-dependent manner, soluble HLA-E was upregulated in conditioned medium. Pre-incubation with anti-NKG2A antibodies increased the activation of NKG2A+ NK cells in the presence of soluble HLA-E. Expression of soluble HLA-E in the serum of GC patients correlated with disease progression. CONCLUSIONS: HLA-E expression dynamically changes on GC cells and in conditioned medium. Furthermore, soluble HLA-E can contribute to immune escape in GC cell lines, which may have significance in clinical practice. Moreover, soluble HLA-E may be a potential prognostic biomarker.

Minimally invasive esophagectomy may contribute to low incidence of postoperative surgical site infection in patients with poor glycemic control.

PURPOSE: High preoperative hemoglobin A1c (HbA1c) levels have been suggested to increase complications after esophagectomy. Minimally invasive esophagectomy (MIE) is less invasive than open esophagectomy (OE) and may reduce postoperative complications. However, it has not been established whether MIE contributes to low morbidity in patients with high preoperative HbA1c levels. Thus, the current study aimed to elucidate the effect of preoperative HbA1c levels on the incidence of complications each after OE and MIE. METHODS: A total of 280 patients who underwent OE and 304 patients who underwent MIE for esophageal cancer between April 2005 and April 2020 were retrospectively analyzed. The OE and MIE groups were further divided into two groups according to their preoperative HbA1c levels (< 6.9%, ≥ 6.9%). RESULTS: Patients with high HbA1c levels had a significantly higher incidence of surgical site infections (SSIs) after OE (P = 0.0048). Multivariate analysis demonstrated that a high HbA1c level was an independent risk factor for frequent SSIs after OE (hazard ratio 2.52; 95% confidence interval, 1.101- 5.739; P = 0.029). On the contrary, a high HbA1c level did not affect the incidence of SSI after MIE (P = 1.00). A high HbA1c level was not associated with the incidence of morbidities other than SSI after OE and MIE. CONCLUSIONS: A high preoperative HbA1c level significantly increased SSI risk after OE but not after MIE. It was suggested that lower invasiveness of MIE could contribute to a low incidence of SSI, even in patients with poor preoperative glycemic control.

Preoperative transferrin level is a novel indicator of short- and long-term outcomes after esophageal cancer surgery.

BACKGROUND: This study aimed to examine whether preoperative serum transferrin, a rapid-turnover protein, correlates with short- and long-term outcomes after esophagectomy. METHODS: Preoperative transferrin levels, calculated by summing serum iron and unsaturated iron-binding capacity, were evaluated in 224 patients who underwent esophagectomy for stage I-III esophageal cancer without preoperative treatment. Transferrin levels are directly proportional to total iron-binding capacity (TIBC), and we defined TIBC < 250 µg/dL as low transferrin. We evaluated the relationship between preoperative transferrin levels and short- and long-term outcomes after esophagectomy using univariate and multivariate Cox proportional hazards analyses. RESULTS: Of all patients, 25 (11.2%) had low preoperative transferrin levels. Low preoperative transferrin levels were strongly correlated with worse preoperative performance status, advanced pathological T stage, and more open esophagectomy (p = 0.0078, 0.0001, and 0.013, respectively). Patients with low preoperative transferrin levels experienced significantly more frequent postoperative pneumonia in univariate and multivariate analysis [hazard ratio (HR) 3.30, 95% confidence interval (CI) 1.032-10.033, p = 0.0443]. Additionally, these patients were significantly correlated with worse overall survival (OS) in univariate and multivariate analyses (HR 2.75, 95% CI 1.018-7.426, p = 0.0460). Furthermore, we investigated the relationship between OS and postoperative pneumonia to elucidate why low preoperative transferrin, which is an independent risk factor for postoperative pneumonia, leads to poor prognosis. Patients with postoperative pneumonia were strongly associated with a shorter OS (p = 0.0099). CONCLUSION: Preoperative serum transferrin levels may be a novel indicator of postoperative pneumonia and OS after esophagectomy.

Laparoscopic Observation of Adhesive Rectal Fixation after Gant-Miwa-Thiersch Procedure for Rectal Prolapse: A Case Report.

In our previous report, we have noted an increase of computed tomography (CT) attenuation values in perirectal fat tissue after Gant-Miwa-Thiersch (GMT) procedure for rectal prolapse. Based on these results, we hypothesized that the GMT procedure may have a rectal fixation effect due to inflammatory adhesions extending to the mesorectum. Herein, we report a case of laparoscopic observation of perirectal inflammation after GMT. A 79-year-old woman with a history of seizures, stroke, subarachnoid hemorrhage, and spondylosis underwent the GMT procedure under general anesthesia in the lithotomy position for rectal prolapse measuring 10 cm in length. But rectal prolapse recurred 3 weeks after surgery. Therefore, an additional Thiersch procedure was performed. However, rectal prolapse still recurred, and laparoscopic suture rectopexy was performed 17 weeks after initial surgery. During rectal mobilization, marked edema and rough membranous adhesions were observed in the retrorectal space. The average CT attenuation value obtained 13 weeks after initial surgery was found to be significantly elevated in the mesorectum compared with the subcutaneous fat, especially in the posterior side (P < 0.05). These findings suggest that the extension of inflammation to the rectal mesentery after the GMT procedure may have strengthened adhesions in the retrorectal space.

Iron accelerates Fusobacterium nucleatum-induced CCL8 expression in macrophages and is associated with colorectal cancer progression.

Accumulating evidence suggests that high levels of Fusobacterium nucleatum in colorectal tumor tissues can be associated with poor prognosis in patients with colorectal cancer (CRC); however, data regarding distinct prognostic subgroups in F. nucleatum-positive CRC remain limited. Herein, we demonstrate that high-iron status was associated with a worse prognosis in patients with CRC with F. nucleatum. Patients with CRC presenting elevated serum transferrin saturation exhibited preferential iron deposition in macrophages in the tumor microenvironment. In addition, F. nucleatum induced CCL8 expression in macrophages via the TLR4/NF-κB signaling pathway, which was inhibited by iron deficiency. Mechanistically, iron attenuated the inhibitory phosphorylation of NF-κB p65 by activating serine/threonine phosphatases, augmenting tumor-promoting chemokine production in macrophages. Our observations indicate a key role for iron in modulating the NF-κB signaling pathway and suggest its prognostic potential as a determining factor for interpatient heterogeneity in F. nucleatum-positive CRC.

Pancreaticoduodenectomy at a Non-high-volume Center and Efforts to Perform Safe Surgery.

AIM: The aim of the current study was to investigate whether the artery-first approach (AFA) improved surgical outcomes of pancreaticoduodenectomy (PD) at our non-high-volume center. PATIENTS AND METHODS: We retrospectively reviewed data on 121 consecutive patients who underwent PD between January 2009 and December 2018. The perioperative data of 49 patients who underwent conventional PD (conventional group) and 72 patients who underwent PD via artery-first approach were analyzed and compared to assess the effectiveness of the AFA. RESULTS: Although no significant difference was observed between the two groups overall, in those with pancreatic cancer, the duration of surgery, intraoperative blood loss and transfusion rate in the AFA group (n=33) were significantly lower than those for the conventional group (n=11) (p=0.011, p=0.021 and p=0.038 respectively). CONCLUSION: AFA can be used to reduce the operative time, intraoperative blood loss, and transfusion rate in patients with pancreatic cancer.

IgG4-related disease presenting as a submucosal tumor of the stomach resected with laparoscopic endoscopic cooperative surgery: a case report.

BACKGROUND: IgG4-related disease (IgG4-RD) is an immune-mediated disorder in which abundant IgG4-positive plasma cells infiltrate affected organs. There have been reported four cases of probable IgG4-RD presenting as a submucosal tumor of the stomach. We herein report the first case of definite IgG4-RD presenting as a submucosal tumor of the stomach resected with laparoscopic endoscopic cooperative surgery (LECS). CASE PRESENTATION: A 70-year-old woman with a 6-year history of autoimmune pancreatitis was referred to our department because a 15-mm submucosal tumor in the greater curvature of the lower part of the stomach had been identified via upper gastrointestinal endoscopy. Endoscopic ultrasonography showed a 10-mm low-echoic lesion derived from the submucosal layer of the stomach. A fine-needle aspiration biopsy was attempted, but the tumor was too hard for sampling. F-fluorodeoxyglucose (FDG) positron emission tomography showed an FDG uptake, suggesting a possibility of malignant disease. As the diagnosis could not be confirmed, LECS for both the diagnosis and curative treatment was performed. A histopathological examination showed a tumor with IgG4-positive lymphoplasmacytic infiltration and fibrosis. The ratio of IgG4+/IgG+ lymphoplasmacytic cells was > 80%. A laboratory examination showed elevation of the serum IgG4 levels preoperatively. Thus, the final diagnosis was IgG4-RD of the stomach. No recurrence was observed within 1 year after surgery. CONCLUSIONS: We encountered a case of definite IgG4-RD presenting as a gastric SMT in which a correct diagnosis was achieved by a minimally invasive LECS technique. IgG4-RD may present as a gastric lesion and should be taken into consideration as a differential diagnosis.

Perforation of the esophagus due to thermal injury after laparoscopic radiofrequency ablation for hepatocellular carcinoma: a case for caution.

BACKGROUND: Several reported complications associated with radiofrequency ablation for liver tumors are due to thermal damage of neighboring organs. We herein report a first case of esophageal perforation due to thermal injury of laparoscopic radiofrequency ablation (RFA). CASE PRESENTATION: A 75-year-old woman was treated repeatedly with RFA (percutaneous and laparoscopic) and transcatheter arterial chemoembolization for hepatocellular carcinoma. One week after laparoscopic RFA for recurrent HCC located in segment 2 of the liver, dysphagia and thoracic pain occurred. Upper gastrointestinal endoscopy revealed a perforated esophageal ulcer at the esophago-gastric junction. Inflammation was localized because of severe intra-abdominal adhesion due to repeat surgery, so we decided to treat the patient conservatively. The perforation of the esophagus gradually scarred, and exacerbation did not occur after restarting oral intake. CONCLUSIONS: When patients with a history of abdominal surgery or intra-abdominal inflammation undergo thermal ablation therapy, caution is required, as there is a possibility of thermal injury of unexpected organs.

Acquired factor V deficiency following transcatheter arterial chemoembolization for hepatocellular carcinoma: a case report.

Acquired factor V deficiency is a rare condition associated with a wide variety of causes. We herein report the case of a 75-year-old man who developed acquired factor V deficiency associated with gastrointestinal bleeding after transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma. Laboratory data revealed prolonged prothrombin time (PT) and activated partial thromboplastin time (APTT) and a significant reduction in the factor V (FV) activity. Infusion of fresh-frozen plasma (FFP) was unable to correct the prolonged PT and APTT. Four weeks after onset, his coagulation parameters improved spontaneously with no particular treatment. The patient developed acquired FV deficiency after TACE treatment using cisplatin, and thus, cisplatin was suspected as the cause of this coagulopathy. If coagulopathy that is not corrected by FFP transfusion after TACE is observed, acquired factor V deficiency, although extremely rare, should be considered.