Tomoyuki Momma

Expression of circadian clock genes in human colorectal adenoma and carcinoma

Circadian rhythms are fundamental biological systems in most organisms. Epidemiological and animal studies have demonstrated that disruption of circadian rhythms is linked to tumor progression and mammalian tumorigenesis. However, the clinical significance of in situ clock gene expression in precancerous and cancerous colorectal lesions remains unknown. The present study aimed to investigate mRNA transcript levels of circadian clock genes within human colorectal cancer and adenoma tissue sections. Using in situ hybridization, the expression of key clock genes, including period circadian protein homolog (Per) 1 and 2, cryptochrome 1 (Cry1), circadian locomoter output cycles protein kaput (Clock), brain and muscle ARNT-like protein 1 (Bmal1) and casein kinase 1ε (CK1ε) were retrospectively examined in 51 cases of colorectal carcinoma and 10 cases of adenoma. The expression of clock genes was almost undetectable in the majority of adenomas, whereas positive expression of clock genes was observed in 27–47% of carcinomas. Notably, positive Per1, Per2 and Clock staining in colorectal carcinomas were each significantly associated with a larger tumor size (P=0.012, P=0.011 and P=0.009, respectively). Tumors with positive Per2 and Clock expression tended to exhibit deeper depth of invasion and were generally more advanced than tumors that did not express these genes (P=0.052 and P=0.064, respectively). However, no statistically significant association was observed between clock gene expression and clinicopathological variables, including histopathological differentiation, lymph node metastasis, depth of invasion or disease stage, although Per2-positive tumors tended to be associated with poorer overall survival (P=0.060). The results of the current study suggest that dysregulated expression of clock genes may be important in human colorectal tumorigenesis.

Stromal VCAN expression as a potential prognostic biomarker for disease recurrence in stage II-III colon cancer.

To develop prognostic biomarkers that can discriminate stage II-III colorectal cancer patients with high risk of postoperative recurrence, we conducted a genome-wide screening of relapse-related genes utilizing multiple microarray cohorts. Among differentially expressed genes between tumor and nontumor, we identified eight candidate genes associated with relapse in two datasets of stage II-III patients (n = 94 and 145, respectively, P < 0.05). Using datasets of laser-microdissected samples and FACS-purified cell populations, the localization of candidate genes, including COL4A2, COL4A1, VCAN and SERPINE1, were found predominantly in cancer stroma rather than epithelial components. Among those relapse-related stromal genes, VCAN mRNA, specifically expressed in cancer-associated fibroblasts, was further validated to be a prognostic factor in two additional independent datasets, consisting of 453 (P = 0.0334) and 89 (P = 0.0041) stage II-III patients. Furthermore, in our large set of formalin-fixed paraffin-embedded cohort (n = 338), VCAN protein was detected exclusively in cancer stroma by immunohistochemistry, demonstrating a stepwise increase of stromal VCAN from normal tissues through stage 0 to stage IV tumors. Stromal VCAN protein was associated with shorter relapse-free survival (RFS) in stage II-III colon cancer, independent of other clinical factors by multivariate analysis (P = 0.004). Stratified analyses revealed that stromal VCAN was a strong prognostic indicator particularly in stage II colon cancer (P = 0.0029). In all five analyzed cohorts, the expression of VCAN, in transcript or protein levels, was associated with poor RFS in stage II-III patients. We conclude that VCAN is a promising biomarker to identify stage II-III patients at high risk of relapse who may benefit from intensive postoperative management.

Enhanced expression of KIF4A in colorectal cancer is associated with lymph node metastasis

Kinesin family member 4A (KIF4A) is a member of the kinesin 4 subfamily of kinesin-related proteins and serves an important role in cell division. The expression levels of KIF4A have been investigated in numerous types of cancer, including cervical, lung, oral, and breast cancer, and are established to be associated with poor patient prognosis. However, the role of KIF4A, as well as its expression in colorectal cancer (CRC), remains to be elucidated. Therefore, the current study investigated KIF4A expression levels in patients with CRC and demonstrated that its levels were increased in tumor tissues compared with non-tumor tissues. To investigate the functional role of KIF4A, KIF4A was knocked down in CRC cells and cell viability was evaluated. CRC cells with KIF4A knockdown exhibited lower cell proliferation compared with control cells. In addition, KIF4A expression levels, as determined by immunohistochemistry, were compared with the expression of Ki-67, but no significant associations were observed in the patients with CRC. Therefore, KIF4A was found to be upregulated in patients with CRC and downregulation of KIF4A reduced cell proliferation in CRC cells. These results suggest that KIF4A may be a potential therapeutic target, which may improve the outcomes of patients with CRC.

Upregulated solute carrier family 37 member 1 in colorectal cancer is associated with poor patient outcome and metastasis

Solute carrier (SLC) drug transporters exchange various molecules without energy from adenosine triphosphate hydrolysis, indicating an association with anticancer drug resistance. However, the expression and role of SLC transporters in malignant tumors has not yet been fully elucidated. Therefore, in the current study, the expression of SLC37A family genes was evaluated in patients with colorectal cancer (CRC), and it was revealed that SLC family 37 member 1 (SLC37A1) expression was significantly increased in tumorous tissues compared with that in non-tumorous tissues. The cases with upregulated expression of SLC37A1 by immunohistochemical staining were significantly associated with positive venous invasion and liver metastasis. Furthermore, upregulated SLC37A1 expression was associated with poor overall survival time in the present cohort. These results indicated that SLC37A1 is involved in the hematogenous metastasis of CRC. To investigate whether SLC37A1 is associated with hematogenous metastasis and glycolipid metabolism, SLC37A1 was knocked down in colon cancer cells, and the expression of sialyl Lewis A and sialyl Lewis X was observed to be decreased. In summary, upregulation of SLC37A1 was observed in patients with CRC, and was associated with poor patient outcomes and survival. To the best of our knowledge, the present study is the first to propose a key role of SLC37A1 in CRC, and additional studies are warranted to reveal the functional role of SLC37A1 in CRC development.

Pathological aspects of the intraductal spread of breast cancer

The intraductal spread of breast cancer is a major cause of local recurrence following breast-conserving therapy. To properly understand this pathology, three-dimensional (3D) cancer localization within the mammary ductal–lobular system (MDLS) is necessary. To this end we generated computer-assisted 3D reconstructions of all MDLSs using 2-mm-thick serial sections of surgically resected specimens. We then analyzed the characteristics of intraductal spread of breast cancer. In our study of quadrantectomy specimens from patients with primary invasive breast carcinoma, the intraductal spread of breast cancer was found to be continuous from the invasive tumor and spreading along the mammary glandular tree. The pattern is categorized into three types: the central type, the peripheral type, and the extensive type. The central type was found to be most common. A 3D analysis of total mastectomy specimen from a patient with primary non-invasive breast carcinoma revealed regional intraductal spread extending within and filling a single MDLS. The analysis also revealed the presence of ductal anastomoses connecting adjacent MDLSs. These ductal anastomoses were found to be an anatomical risk factor for extensive intraductal spread of breast cancer across multiple MDLSs. To minimize residual non-invasive components of breast carcinoma in the conserved breast, which is strongly associated with the outcome of local control of breast-conserving therapy, it is necessary to determine the optimum surgical margins in a flexible, patient-specific manner. This determination should be based on anatomical characteristics of the MDLS, such as those identified in the present study.

Prognostic role of FUT8 expression in relation to p53 status in stage II and III colorectal cancer

The expression of fucosyltransferase 8, an enzyme responsible for core fucosylation encoded by FUT8, influences tumor biology and correlates with patient prognosis in several solid cancers. We hypothesized that p53 alteration modifies prognostic associations of FUT8 expression in colorectal cancer (CRC), since FUT8 has recently been identified as a direct transcriptional target of wild-type p53. Utilizing multiple datasets of microarray and RNA sequence of CRC, FUT8 mRNA was found to be highly expressed in wild-type p53 tumors (n = 382) compared to those of mutant p53 (n = 437). Prognostic values of FUT8 expression in conjunction with the p53 status for disease-free survival (DFS) were analyzed using two independent cohorts of stage II and III CRC after curative surgery, including the immunohistochemistry (IHC) cohort (n = 123) and the microarray cohort (n = 357). In both cohorts, neither FUT8 expression nor the p53 status was associated with DFS. Strikingly, positive expression of FUT8 protein was significantly associated with better DFS only in tumors with negative p53, while it had no prognostic impact in tumors with positive p53 in the IHC cohort. Although not statistically significant, a similar prognostic trend was observed in the microarray cohort when patients were stratified by the p53 status. Our results suggest that the prognostic values of FUT8 expression on DFS may be modified by the p53 status, and the expression of FUT8 protein can be a prognostic biomarker for patients with stage II and III CRC.

Poland syndrome accompanied by internal iliac artery supply disruption sequence: a case report

BackgroundPoland syndrome is a congenital malformation characterized by ipsilateral hand and chest wall depression, including an absence or hypoplasia of the breast and pectoral muscles. These hypoplastic defects are reportedly caused by a subclavian artery supply disruption sequence.Case presentationA 45-year-old Japanese woman, an out-patient, underwent an emergency examination for intense left lower abdominal pain. Computed tomography images revealed a hydronephrotic left kidney and dilatation of the left ureter. No ureteral calculus or neoplasm was found. In addition, no abnormalities connected to her left abdominal pain were found. Nephritis was diagnosed based on the results of urine analysis, and a course of antibiotics was administered. Computed tomography images also revealed a history of breast reconstruction with a custom-made silicone implant in her right breast. The present case showed symptoms of Poland syndrome, which were absence of the sternal head of the right pectoralis major and asymmetrical malformation of the chest wall due to hypoplasia of the right rib cage. In addition to typical Poland syndrome symptoms, she had hypoplasia of her right kidney, hypoplasia of the right gluteus minimus muscle, right-sided pelvic hypoplasia, spinal curvature to the right, and a cystic mass in her right ovary.ConclusionsIn the present case of Poland syndrome, computed tomography images revealed malformation of the chest wall, absence of the pectoral muscle, and hypoplasia of a left kidney. Unilateral visceral hypoplasia is reported to be caused by a subclavian artery supply disruption sequence that occurs around 7 to 8 weeks of gestation. The present case can be considered a rare atypical phenotype of Poland syndrome with possible subclavian artery supply disruption sequence with internal iliac artery supply disruption.

Targeted therapy according to next generation sequencing-based panel sequencing

Targeted therapy against actionable gene mutations shows a significantly higher response rate as well as longer survival compared to conventional chemotherapy, and has become a standard therapy for many cancers. Recent progress in next-generation sequencing (NGS) has enabled to identify huge number of genetic aberrations. Based on sequencing results, patients recommend to undergo targeted therapy or immunotherapy. In cases where there are no available approved drugs for the genetic mutations detected in the patients, it is recommended to be facilitate the registration for the clinical trials. For that purpose, a NGS-based sequencing panel that can simultaneously target multiple genes in a single investigation has been used in daily clinical practice. To date, various types of sequencing panels have been developed to investigate genetic aberrations with tumor somatic genome variants (gain-of-function or loss-of-function mutations, high-level copy number alterations, and gene fusions) through comprehensive bioinformatics. Because sequencing panels are efficient and cost-effective, they are quickly being adopted outside the lab, in hospitals and clinics, in order to identify personal targeted therapy for individual cancer patients.

Immunotherapy for esophageal squamous cell carcinoma: a review

Cancer vaccines and immune checkpoint inhibitors (ICI) have recently been employed as immunotherapies for esophageal squamous cell carcinoma (ESCC). Cancer vaccines for ESCC have yielded several promising results from investigator-initiated phase I and II clinical trials. Furthermore, a Randomized Controlled Trial as an adjuvant setting after curative surgery is in progress in Japan. On the other hand, ICI, anti-CTLA-4 mAb and anti-PD-1 mAb, have demonstrated tumor shrinkage and improved overall survival in patients with multiple cancer types. For ESCC, several clinical trials using anti-PD-1/anti-PD-L1 mAb are underway with several recent promising results. In this review, cancer vaccines and ICI are discussed as novel therapeutic strategies for ESCC.

Prognostic impact of preoperative lymphocyte-to-monocyte ratio in patients with colorectal cancer with special reference to myeloid-derived suppressor cells

AIMS We aimed to investigate the relationship of colorectal cancer prognosis and inflammatory parameters, including neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR), with reference to circulating myeloid-derived suppressor cells (MDSCs) in the current study. PATIENTS AND METHODS Thirty-five patients who underwent curative-intent surgery were enrolled.　A receiver-operating characteristic curve (ROC) was used to assess the usefulness of candidates for prognostic factors. Recurrence-free survival (RFS) was calculated using the Kaplan-Meier method, and the candidates for prognostic factors were assessed by a Cox proportional hazard model. RESULTS ROC curve analyses determined cutoff values for NLR and LMR as 2.9 and 2.4, respectively. The percentage of MDSCs in patients with LMR ≤ 2.4 was statistically higher than in those with LMR > 2.4 (p = 0.012). The patients with LMR ≤ 2.4 exhibited a statistically lower RFS than those with LMR > 2.4 (p = 0.008). These results were also observed in patients with stage II + III disease. LMR was an independent prognostic factor of RFS in colorectal cancer patients (hazard ratio: 7.757, 95% confidence interval: 1.462-41.152, p = 0.016). CONCLUSION Lower LMR was associated with poor prognosis in colorectal cancer patients; whereas, higher circulating MDSCs were observed in patients with lower LMR.