Kei Yoshino

IGFBP3 and BAG1 enhance radiation-induced apoptosis in squamous esophageal cancer cells

Identification of reliable markers of radiosensitivity and the key molecules that enhance the susceptibility of esophageal cancer cells to anticancer treatments would be highly desirable. To identify molecules that confer radiosensitivity to esophageal squamous carcinoma cells, we assessed the radiosensitivities of the TE-5, TE-9 and TE-12 cloneA1 cell lines. TE-12 cloneA1 cells showed significantly greater susceptibility to radiotherapy at 5 and 10Gy than either TE-5 or TE-9 cells. Consistent with that finding, 24h after irradiation (5Gy), TE-12 cloneA1 cells showed higher levels of caspase 3/7 activity than TE-5 or TE-9 cells. When we used DNA microarrays to compare the gene expression profiles of TE-5 and TE-12 cloneA1 cells, we found that the mRNA and protein expression of insulin-like growth factor binding protein 3 (IGFBP3) and Bcl-2-associated athanogene 1 (BAG1) was five or more times higher in TE-12 cloneA1 cells than TE-5 cells. Conversely, knocking down expression of IGFBP3 and BAG1 mRNA in TE-12 cloneA1 cells using small interfering RNA (siRNA) significantly reduced radiosensitivity. These data suggest that IGFBP3 and BAG1 may be key markers of radiosensitivity that enhance the susceptibility of squamous cell esophageal cancer to radiotherapy. IGFBP3 and BAG1 may thus be useful targets for improved and more individualized treatments for patients with esophageal squamous cell carcinoma.

Diagnostic imaging in the preoperative management of lung cancer

Surgical resection is the accepted standard of care for patients with non-small cell lung cancer (NSCLC). Several imaging modalities play central roles in the detection and staging of the disease. The aim of this review is to evaluate the utility of computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET) and PET/CT for NSCLC staging. Radiographic staging refers to the use of CT as a non-invasive diagnostic technique. However, while the vast majority of patients undergo only CT, CT is a notoriously inaccurate means of tumor and nodal staging in many situations. PET/CT clearly improves the staging, particularly nodal staging, compared to CT or PET alone. In addition, as a result of the increased soft-tissue contrast, MRI is superior to CT for distinguishing between tissue characteristics. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA), which is a minimally invasive technique, also has pathological diagnostic potential. Extensive research and the resultant improvements in the understanding of genetics, histology, molecular biology and oncology are transforming our understanding of lung cancer, and it is clear that imaging modalities such as CT, MRI, PET and PET/CT will have an important role in its preoperative management. However, thoracic surgeons should also be aware of the limitations of these techniques.

Therapeutic strategy for the treatment of postoperative recurrence of esophageal squamous cell carcinoma: clinical efficacy of radiotherapy.

We investigated the effectiveness of chemoradiotherapy for the treatment of lymph node recurrence and hematogenous metastasis after esophagectomy for esophageal squamous cell carcinoma. Between 2001 and 2006, 216 patients with thoracic esophageal squamous cell carcinoma had curative esophagectomy. Of those, 23 with lymph node recurrence received chemoradiotherapy (50.0-68.8 Gy). In addition, five patients had isolated recurrences in a distant organ and received chemoradiotherapy (50.0-60.0 Gy). We analyzed outcomes from the radiotherapy for recurrent esophageal cancer. The 1-, 2-, and 5-year survival rates after recurrence for the 23 patients whose lymph node recurrence was treated with chemoradiotherapy were 52, 31, and 24%, respectively, and the median survival time was 13 months. Among the five patients with recurrent tumors in a distant organ, chemoradiotherapy produced a complete response in two patients, a partial response in one patient, and stable disease in two patients, giving an effectiveness rate of 60% (complete response + partial response). Chemoradiotherapy has a beneficial prognostic effect in patients with lymph node recurrence of esophageal squamous cell carcinoma. Chemoradiotherapy for a metastatic tumor in a distant organ may be the treatment of choice in cases where systemic chemotherapy has proven ineffective.

Esophageal Cancer Patients Have a High Incidence of Severe Periodontitis and Preoperative Dental Care Reduces the Likelihood of Severe Pneumonia after Esophagectomy

Background: Poor oral health is a risk factor for causing upper aerodigestive tract tumors, including esophageal cancer. Our aim was to determine the periodontitis rate in our cohort of esophageal cancer patients. We also analyzed whether preoperative dental examination and care reduces the likelihood of severe pneumonia after esophagectomy. Study Design: Between 2003 and 2014, 529 esophageal cancer patients received esophagectomy at Akita University Hospital. We studied 232 patients who had preoperative dental examinations and care (dental care group) retrospectively and assessed the severity of their periodontitis. The dental care group was compared to 297 patients who did not have preoperative dental care (control group) with respect to the incidence of severe pneumonia after esophagectomy. Results: Ninety-one patients (39.2%) in the dental care group were diagnosed with slight periodontitis and 69 (29.7%) were diagnosed with severe periodontitis. Among all the patients, 69 patients (13.0%) were diagnosed with grade 3B postoperative severe pneumonia. The dental care group had a significantly lower incidence of severe pneumonia than the control group. Moreover, multivariable logistic regression analysis revealed that anastomotic leakage, preoperative dental care, gender and %VC were correlated significantly with the occurrence of postoperative severe pneumonia. Conclusion: Preoperative dental examination and care by a dentist are essential to reduce the likelihood of postoperative severe pneumonia in esophageal cancer patients.

C-reactive protein inhibits lymphangiogenesis and resultant lymph node metastasis of squamous cell carcinoma in mice

BACKGROUND Lymph node involvement is the most important prognostic factor in many solid cancers. Recently, we found that patients with esophageal and lung cancer carrying the C-reactive protein (CRP) 1846T/T genotype, which is associated with lower serum CRP levels, are more likely to have lymph node metastasis. We hypothesized that host CRP directly inhibits lymph node metastasis. METHODS We inoculated NR-S1M metastatic cells subcutaneously into the backs of C3H/HeN mice. Concurrently, 1 μg of recombinant mouse CRP or phosphate-buffered saline was injected subcutaneously every 3 days for 5 weeks, after which the mice were killed for evaluation. We evaluated lymph node metastasis and lymphangiogenesis in the implanted tumor by using immunohistochemical analysis with anti-pancytokeratin and antilymphatic vessel endothelial hyaluronan receptor-1 antibodies. RESULTS There was no substantial difference in tumor size between the 2 groups but the lymph nodes were smaller in the CRP group than the control group (P < .044). Immunohistochemical analysis confirmed inguinal lymph node metastasis in 70% (14/20) of control mice, but in only 30% (3/10) of mice in the CRP group. Moreover, the metastatic area within lymph nodes was less in the CRP group (P < .042) and tumoral lymphangiogenesis was decreased in the CRP group (P < .037). CONCLUSION CRP appears to inhibit tumoral lymphangiogenesis and lymph node metastasis in mice. These findings suggest that by inhibiting lymph node metastasis, CPR may have therapeutic potential for use against cancer.

Interleukin-2 −330T>G Genetic Polymorphism Associates with Prognosis Following Surgery for Thoracic Esophageal Squamous Cell Cancer

BackgroundKey molecules in the T helper (Th)1 and Th2 pathways underlie differential responses to the progression and surgical treatment of cancer. We investigated the relationship between Th1/Th2 cytokine polymorphism and prognosis in patients with thoracic esophageal squamous cell cancer.Materials and MethodsThe study participants were 159 Japanese patients treated for thoracic esophageal squamous cell cancer with curative esophagectomy at Akita University Hospital. We determined the associations between prognosis following esophagectomy and genetic polymorphisms in Th1 cytokines (interleukin [IL]-2, Interferon-γ, IL-12β), and Th2 cytokines (IL-4, IL-10).ResultsIL-2 −330T>G genetic polymorphism was significantly associated with prognosis after esophagectomy. Univariate and multivariate analyses using a Cox proportional hazards model revealed that patients carrying the IL-2 −330G/G genotype had a significantly poorer prognosis than those carrying the T/G or T/T genotype. However, IL-2 −330T>G polymorphism was not associated with preoperative serum IL-2 levels. Moreover, interferon-γ, IL-12β, IL-4, and IL-10 genetic polymorphisms were not associated with prognosis after esophagectomy for thoracic esophageal squamous cell cancer.ConclusionsIt is suggested that IL-2 −330T>G genetic polymorphism may be a predictive factor for prognosis in patients receiving esophagectomy for thoracic esophageal squamous cell cancer.

REG Iα activates c-Jun through MAPK pathways to enhance the radiosensitivity of squamous esophageal cancer cells

Identification of the key molecules that mediate susceptibility to anticancer treatments would be highly desirable. Based on clinical and cell biological studies, we recently proposed that regenerating gene (REG) Iα may be such a molecule. In the present study, we hypothesized that REG Iα increases radiosensitivity through activation of mitogen-activated protein kinase (MAPK) pathways. To test that idea, we transfected TE-5 and TE-9 squamous esophageal cancer cells with REG Iα and examined its involvement in MAPK signaling and its effect on susceptibility to radiotherapy. We found that REG Iα-expressing cells showed increased expression of c-Jun messenger RNA (mRNA) and phospho-c-Jun protein mediated via the c-Jun N-terminal kinase (JNK) pathway and extracellular signal-regulated kinase (ERK) pathway, as well as increased radiosensitivity. Immunohistochemical analysis confirmed the activation of c-Jun in tumors expressing REG Iα. Collectively, these findings suggest that REG Iα activates c-Jun via the JNK and ERK pathway, thereby enhancing radiosensitivity.

Identification of insulin-like growth factor 2 mRNA-binding protein 3 as a radioresistance factor in squamous esophageal cancer cells

Identification of reliable markers of radiosensitivity and the key molecules that donate susceptibility to anticancer treatments to esophageal cancer cells would be highly desirable. We found that the mRNA expression of insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) was higher in radioresistant TE-5 and TE-9 cells than in radiosensitive TE-12 cloneA1 cells. Conversely, knocking down expression of IGF2BP3 mRNA in TE-5 and TE-9 cells using small interfering RNA significantly enhanced their radiosensitivity. Furthermore, patients with squamous cell esophageal cancers strongly expressing IGF2BP3 tended to respond poorly to chemoradiation. These data suggest that IGF2BP3 may be a key marker of radiosensitivity that diminishes the susceptibility of squamous cell esophageal cancer cells to radiotherapy. IGF2BP3 may, thus, be a useful target for improving radiotherapy for patients with esophageal squamous cell carcinoma.

Two cases of cisplatin-induced permanent renal failure following neoadjuvant chemotherapy for esophageal cancer

Highlights • Two esophageal cancer patients developed severe acute renal failure after neoadjuvant chemotherapy with cisplatin and 5-fluorourasil.• Volume expansion remains the most effective strategy for prevention of cisplatin nephrotoxicity.• The two patients described here received sufficient drip infusion and produced good urine volumes.• In both cases, renal biopsy examination indicated partial recovery of the proximal tubule, but renal function did not recover.

Development of a New Magnetometer for Sentinel Lymph Node Mapping Designed for Video-Assisted Thoracic Surgery in Non–Small Cell Lung Cancer

Background. We previously developed a method for sentinel lymph node (SLN) mapping in non–small cell lung cancer (NSCLC), based on the magnetic force produced by a magnetite tracer already approved for use as a contrast material for magnetic resonance imaging. However, it is difficult to use that technique with video-assisted thoracic surgery (VATS) because the sensing element of the magnetometer is large and thick. The purpose of the present study was to develop a smaller, thinner VATS-compatible magnetometer. Methods. The tracer employed was Ferucarbotran, a colloidal solution of superparamagnetic iron oxide coated with carbodextran. Fifteen patients with clinical stage I NSCLC were enrolled, and each received 1.6 mL of Ferucarbotran, injected intraoperatively at 5 points around the tumor. The magnetic force within the sampling lymph nodes was measured using the new VATS-compatible magnetometer. Results. SLNs were detected in 11 (73.3%) of the 15 patients using the VATS-compatible magnetometer. The average number of SLNs identified per patient was 1.8 (range 0-4). No complications related to the SLN detection method were observed. Conclusions. The new VATS-compatible magnetometer appears to have substantial advantages over techniques using a radioisotope and our earlier magnetometer, as it can be inserted through the small VATS port site.