Mitochondria‐eating protein (Mieap), encoded by a p53‐target gene, plays an important role in mitochondrial quality control (MQC). Mieap has been reported to have a critical role in tumor suppression in colorectal cancer. Here, we investigated its role as a tumor suppressor in breast cancer. The enforced expression of exogenous Mieap in breast cancer cells induced caspase‐dependent apoptosis, with activation of both caspase‐3/7 and caspase‐9. Immunohistochemistry revealed endogenous Mieap in the cytoplasm in 24/75 (32%) invasive ductal carcinomas (IDC), 15/27 (55.6%) cases of ductal carcinoma in situ (DCIS) and 16/18 (88.9%) fibroadenomas (FA) (IDC vs DCIS; P = 0.0389, DCIS vs FA; P = 0.0234, IDC vs FA; P < 0.0001). In IDC, the Mieap promoter was methylated in 6/46 (13%) cases, whereas p53 was mutated in 6/46 (13%) cases. Therefore, the p53/Mieap‐regulated MQC pathway was inactivated in 12/46 IDC (26.1%). Interestingly, all tumors derived from the 12 patients with Mieap promoter methylation or p53 mutations pathologically exhibited more aggressive and malignant breast cancer phenotypes. Impairment of p53/Mieap‐regulated MQC pathway resulted in significantly shorter disease‐free survival (DFS) (P = 0.021), although p53 status is more prognostic in DFS than Mieap promoter methylation. These results indicate that p53/Mieap‐regulated MQC has a critical role in tumor suppression in breast cancer, possibly in part through mitochondrial apoptotic pathway.

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Glycoprotein non-metastatic B (GPNMB), a type I transmembrane glycoprotein, is overexpressed in melanoma and breast cancer and promotes cancer-cell invasion and motility. We previously reported cross-talk between GPNMB and human epidermal growth factor receptor 2 (HER2) in breast cancer, suggesting that GPNMB might play an important role in resistance to anti-HER2 therapy in breast cancer. Here, we clarified the association between GPNMB and HER-family proteins in gastrointestinal cancer by examining their relationships using gastric and colorectal cancer cell lines. We found that GPNMB depletion of by small-interfering RNA increased epidermal growth factor receptor (EGFR) expression and phosphorylation through AKT8 virus oncogene cellular homolog (AKT) and mitogen-activated protein kinase (MAPK) pathways. Additionally, treatment with cetuximab (CTX) also increased GPNMB expression, and combination therapy consisting of GPNMB depletion and CTX treatment significantly suppressed cell growth in colorectal cancer cell lines, but not in gastric cancer cell lines. Furthermore, we also evaluated changes in GPNMB expression in vivo, with immunohistochemistry detecting GPNMB overexpression in a colorectal cancer patient following anti-EGFR therapy. These results suggested possible cross-talk between GPNMB and EGFR, and that GPNMB might play an important role in resistance to anti-EGFR therapy in gastrointestinal cancer.

Background Even if 3D angiographic images of preoperative contrast-enhanced computed tomography (CT) are created, the coronal and axial sections can be unclear, and thus, it is difficult to achieve projection awareness similar to that of actual laparoscopic images. In recent years, the technology of analyzing and applying medical images has advanced, and surgical simulation and navigation have been widely used to improve the safety of surgical operations. It is important to understand pelvic anatomy in the area of rectal cancer, and use of the SYNAPSE VINCENT makes it possible to simulate the anatomy before surgery, which is very useful in educating surgeons and their assistants. Materials and methods An important objective in surgery is to understand the anatomy of the external/internal iliac arteries and lymph nodes in lateral lymph node dissection (LLD) for rectal cancer. In this study, we explored the accuracy and usefulness of SYNAPSE VINCENT images of pelvic anatomy (especially vascular anatomy) analyzed preoperatively in two cases of LLD for rectal cancer in our department. Results The patients were two men aged 73 and 57 years, respectively. Both patients underwent robotic abdominal perineal resection and LLD with neoadjuvant chemoradiotherapy. The operating times for LLD were 138 and 106 min, estimated blood loss was less than 10 mL and 20 mL, and the harvested lymph nodes were nos. 21 and 22, respectively. The SYNAPSE VINCENT could be used for simulation and navigation before and during surgery. For experienced surgeons, the system helped them carry out operations more accurately. Conclusion In the future, surgical support using virtual reality, augmented reality, and mixed reality based on medical images will be useful and is expected to improve the safety, accuracy, and efficiency of surgery, which is extremely useful for both young and skilled surgeons preparing for difficult operations.

Background/Aim: Prognostic nutritional index (PNI) and neutrophil-to-lymphocyte ratio (NLR) indicate nutritional status and host immunity. We used immunohistochemistry and apparent diffusion coefficient (ADC) values calculated using diffusion-weighted imaging (DWI) to investigate relationships of these factors with pathological and radiological characteristics in rectal cancer treated with neoadjuvant chemoradiotherapy (nCRT). Patients and Methods: We evaluated expression levels of VEGFA, CD8, CD33, and ADC values in tumors pre/post nCRT; and analyzed the relationships between those factors and PNI, NLR in 32 patients. Results: Pretreatment PNI negatively correlated with change in tumor stromal CD8+ T cells and positively correlated with ADC values. Pretreatment NLR and PNI change correlated with recurrence-free survival (RFS). Conclusion: Patients with higher pretreatment PNI had greater changes in ADC values and stromal CD8+ T-cell counts, and those with greater PNI reduction from nCRT had a worse prognosis. Proper nutritional management during nCRT benefits patients and may lead to better prognosis in rectal cancer.