Esophageal squamous cell carcinoma (ESCC) is one of the most aggressive malignancies owing to the high frequency of tumor recurrence. The identification of markers for early ESCC diagnosis and prediction of recurrence is expected to improve the long-term prognosis. Therefore, we searched for associations between tumor recurrence and cell-free DNA (cfDNA) mutations in blood plasma, which contains genetic markers for various cancer types.

Early detection and treatment are of vital importance to the successful eradication of various cancers, and development of economical and non-invasive novel cancer screening systems is critical. Previous reports using canine scent detection demonstrated the existence of cancer-specific odours. However, it is difficult to introduce canine scent recognition into clinical practice because of the need to maintain accuracy. In this study, we developed a Nematode Scent Detection Test (NSDT) using Caenorhabditis elegans to provide a novel highly accurate cancer detection system that is economical, painless, rapid and convenient. We demonstrated wild-type C. elegans displayed attractive chemotaxis towards human cancer cell secretions, cancer tissues and urine from cancer patients but avoided control urine; in parallel, the response of the olfactory neurons of C. elegans to the urine from cancer patients was significantly stronger than to control urine. In contrast, G protein α mutants and olfactory neurons-ablated animals were not attracted to cancer patient urine, suggesting that C. elegans senses odours in urine. We tested 242 samples to measure the performance of the NSDT, and found the sensitivity was 95.8%; this is markedly higher than that of other existing tumour markers. Furthermore, the specificity was 95.0%. Importantly, this test was able to diagnose various cancer types tested at the early stage (stage 0 or 1). To conclude, C. elegans scent-based analyses might provide a new strategy to detect and study disease-associated scents.

The anti-VEGF humanized antibody bevacizumab suppresses various malignancies, but tumors can acquire drug resistance. Preclinical studies suggest myeloid-derived suppressor cells (MDSCs) may be associated with tumor refractoriness to anti-VEGF treatment. Here we report a novel mechanism of tumor escape from anti-VEGF therapy. Anti-VEGF treatment enhanced intratumoral recruitment of CD11bhigh/Gr-1high polymorphonuclear (PMN)-MDSCs in anti-VEGF-resistant Lewis lung carcinoma tumors. This effect was diminished by the anticancer agent capecitabine, a pro-drug converted to 5-fluorouracil, but not by 5-fluorouracil itself. This process was mediated by enhanced intratumoral granulocyte-colony stimulating factor expression, as previously demonstrated. However, neither interleukin-17 nor Bv8, which were previously identified as key contributors to anti-VEGF resistance, was involved in this model. Capecitabine eliminated PyNPase-expressing MDSCs from both tumors and peripheral blood. Capecitabine treatment also reversed inhibition of both antitumor angiogenesis and tumor growth under anti-VEGF antibody treatment, and this effect partially inhibited in tumors implanted in mice deficient in both PyNPases. These results indicate that intratumoral granulocyte-colony stimulating factor expression and CD11bhigh/Gr-1high PMN-MDSC recruitment underlie tumor resistance to anti-VEGF therapy, and suggest PyNPases are potentially useful targets during anti-angiogenic therapy.

DNA aneuploidy is observed in various human tumors and is associated with the abnormal expression of spindle assembly checkpoint (SAC) proteins. Oxidative stress (OS) causes DNA damage and chromosome instability that may lead to carcinogenesis. OS is also suggested to contribute to an increase in aneuploid cells. However, it is not clear how OS is involved in the regulation of SAC and contributes to carcinogenesis associated with aneuploidy. Here we show that an oxidant (KBrO3) activated the p53 signaling pathway and suppressed the expression of SAC factors, BubR1, and Mad2, in human diploid fibroblast MRC5 cells. This suppression was dependent on functional p53 and reactive oxygen species. In p53 knockdown cells, KBrO3 did not suppress BubR1 and Mad2 expression and increased both binucleated cells and cells with >4N DNA content. BubR1 and not Mad2 downregulation suppressed KBrO3-induced binucleated cells and cells with >4N DNA content in p53 knockdown cells, suggesting that BubR1 contributes to enhanced polyploidization by a mechanism other than its SAC function. In analysis of 182 gastric cancer specimens, we found that BubR1 expression was significantly high when p53 was positively stained, which indicates loss of p53 function (P = 0.0019). Moreover, positive staining of p53 and high expression of BubR1 in tumors were significantly correlated with DNA aneuploidy (P = 0.0065). These observations suggest that p53 deficiency may lead to the failure of BubR1 downregulation by OS and that p53 deficiency and BubR1 accumulation could contribute to gastric carcinogenesis associated with aneuploidy.

Induced pluripotent stem cells (iPSCs) can be generated from differentiated human and mouse somatic cells using transcription factors such as Oct4, Sox2, Klf4, and c-Myc. It is possible to augment the reprogramming process with chemical compounds, but issues related to low reprogramming efficiencies and, with a number of protocols, residual vector sequences, remain to be resolved. We show here that it is possible to reprogram mouse and human cells to pluripotency by direct transfection of mature double-stranded microRNAs (miRNAs). Our approaches use a combination of mir-200c plus mir-302 s and mir-369 s family miRNAs. Because this reprogramming method does not require vector-based gene transfer, it holds significant potential for biomedical research and regenerative medicine.

Anti-epidermal growth factor receptor (EGFR) therapy has been found to be more effective against left-sided colorectal cancer (LCRC) than right-sided colorectal cancer (RCRC). We hypothesized that RCRC is more likely to harbor genetic alterations associated with resistance to anti-EGFR therapy and tested this using comprehensive genomic sequencing.

The formation of premetastatic niches creates a fertile environment for the seeding of disseminated cancer cells in selected secondary organs. This is crucial for the development of metastasis in various malignancies, including breast cancer (BC). We previously reported that the loss of FBXW7 in bone marrow-derived stromal cells promoted cancer metastasis by increasing the production of the chemokine CCL2, which attracts myeloid-derived suppressor cells and macrophages to the premetastatic niche. Furthermore, treatment with the CCL2 inhibitor propagermanium (PG), which has been used in Japan as a therapeutic agent against chronic hepatitis B, was shown to block the enhancement of metastasis in FBXW7-deficient mice through inhibiting the formation of premetastatic niches. Here, we describe a phase I dose-escalation study of PG used as an antimetastatic drug for perioperative patients with primary BC. The primary end-point was the percentage of patients who experience dose-limiting toxicity. Twelve patients were enrolled in the study. Dose-limiting toxicity was not observed, and the maximum dose was determined to be 90 mg/body/day. The serum concentrations of PG were nearly within the normal range in all observation days. We observed an inverse correlation between FBXW7 mRNA levels in blood and the serum concentrations of CCL2 and interleukin (IL)-6, in agreement with our previous mouse model. Also, IL-6 was downregulated in a PG dose-dependent manner, as observed in mice. Thus, PG was given safely and it is expected to have antimetastatic potential in BC. This trial is registered in the UMIN Clinical Trials Registry as UMIN000022494.

ARID1A, one of the subunits in SWI/SNF chromatin remodeling complex, is frequently mutated in gastric cancers with microsatellite instability (MSI). The most frequent MSI in solid-type poorly differentiated adenocarcinoma (PDA) has been reported, but the SWI/SNF complex status in solid-type PDA is still largely unknown. We retrospectively analyzed 54 cases of solid-type PDA for the expressions of mismatch repair (MMR) proteins (MLH1, PMS2, MSH2, and MSH6), SWI/SNF complex subunits (ARID1A, INI1, BRG1, BRM, BAF155, and BAF170) and EBER, and mutations in KRAS and BRAF. We analyzed 40 cases of another histological type of gastric cancer as a control group. The solid-type PDAs showed coexisting glandular components (76%), MMR deficiency (39%), and complete/partial loss of ARID1A (31%/7%), INI1 (4%/4%), BRG1 (48%/30%), BRM (33%/33%), BAF155 (13%/41%), and BAF170 (6%/2%), EBER positivity (4%), KRAS mutation (2%), and BRAF mutation (2%). Compared to the control group, MMR deficiency and losses of ARID1A, BRG1, BRM, and BAF155 were significantly frequent in solid-type PDAs. Mismatch repair deficiency was associated with the losses of ARID1A, BRG1, and BAF155 in solid-type PDAs. In the MMR-deficient group, solid components showed significantly more frequent losses of ARID1A, BRG1, BRM, and BAF155 compared to glandular components (P = .0268, P = .0181, P = .0224, and P = .0071, respectively). In the MMR-proficient group, solid components showed significantly more frequent loss of BRG1 compared to glandular components (P = .012). In conclusion, solid-type PDAs showed frequent losses of MMR proteins and the SWI/SNF complex. We suggest that loss of the SWI/SNF complex could induce a morphological shift from differentiated-type adenocarcinoma to solid-type PDA.

Gastric cancer (GC) is one of the most lethal malignant tumors. To improve the prognosis of GC, the identification of novel driver genes as therapeutic targets is in urgent need. Here, we aimed to identify novel driver genes and clarify their roles in gastric cancer. OSBPL3 was identified as a candidate driver gene by in silico analysis of public genomic datasets. OSBPL3 expression was analyzed by RT-qPCR and immunohistochemistry in GC cells and tissues. The biological functions and mechanisms of OSBPL3 in GC were examined in vitro and in vivo using GC cells. The association between OSBPL3 expression and clinical outcome in GC patients was also evaluated. Overexpression of OSBPL3 was detected in GC cells with OSBPL3 DNA copy number gains and promoter hypomethylation. OSBPL3-knockdown reduced GC cell growth in vitro and in vivo by inhibiting cell cycle progression. Moreover, an active Ras pull-down assay and western blotting demonstrated that OSBPL3 activates the R-Ras/Akt signaling pathway in GC cells. In a clinical analysis of two GC datasets, high OSBPL3 expression was predictive of a poor prognosis. Our findings suggest that OSBPL3 is a novel driver gene stimulating the R-Ras/Akt signaling pathway and a potential therapeutic target in GC patients.

Circulating tumor DNA (ctDNA) genotyping may guide targeted therapy for patients with advanced GI cancers. However, no studies have validated ctDNA genotyping for microsatellite instability (MSI) assessment in comparison with a tissue-based standard.

Drugs are expected to recover the cell system away from the impaired state to normalcy through disease treatment. However, the understanding of gene regulatory machinery underlying drug activity or disease pathogenesis is far from complete. Here, we perform large-scale regulome analysis for various diseases in terms of gene regulatory machinery. Transcriptome signatures were converted into regulome signatures of transcription factors by integrating publicly available ChIP-seq data. Regulome-based correlations between diseases and their approved drugs were much clearer than the transcriptome-based correlations. For example, an inverse correlation was observed for cancers, whereas a positive correlation was observed for immune system diseases. After demonstrating the usefulness of the regulome-based drug discovery method in terms of accuracy and applicability, we predicted new drugs for nonsmall cell lung cancer and validated the anticancer activity in vitro. The proposed method is useful for understanding disease-disease relationships and drug discovery.

The detection and sequencing of the mutated ctDNA is one of the irreplaceable clinical measures in the postoperative management of colorectal cancer (CRC) cases. However, we are curious to comprehend the essential traits of mutated genes comprising metastatic sites out of whole mutated genes in primary sites. In the current retrospective study, we conducted target resequencing of ctDNA using 47 plasma samples and established a cancer panel carrying the commonly mutated genes between primary and recurrent tumors. We found that mutated genes in ctDNA indicated immune-resistance traits with respect to the impaired ability to present neoantigens by loss of expression or binding affinity to HLA in the primary tumor. Compared with the estimated neoantigens from all mutated genes in primary tumors, the neoantigen peptides from commonly mutated genes on the panel showed abundant expression but no binding affinity to HLA. Therefore, ctDNA mutations can be frequently and postoperatively detected to identify recurrence; however, these mutated genes were derived from immune-tolerated clones owing to the loss of neoantigen presentation in primary CRC tumors.

Serum microRNAs (miRNAs) have been recognized as potential stable biomarkers for various types of cancer. Considering the clinical applications, there are certain critical requirements, such as minimizing the number of miRNAs, reproducibility in a longitudinal clinical course, and superiority to conventional tumor markers, such as carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9. This study aimed to identify serum miRNAs that indicate the recurrence of colorectal cancer (CRC), surpassing inter-tumor heterogeneity.

CD44 is a widely expressed polymorphic adhesion molecule that has pleiotropic functions in development and tumor progression. Its mRNA undergoes alternative splicing to generate multiple variant (CD44v) isoforms, although the function of each CD44v isoform is not fully elucidated. Here, we show that CD44v plays an important role in the induction of vimentin expression upon transforming growth factor-β1 (TGF-β1)-induced epithelial-mesenchymal transition (EMT). Among multiple CD44v isoforms expressed in NUGC3 gastric cancer cells, CD44v8-10 and CD44v3,8-10 are involved in the acquisition of migratory and invasive properties associated with TGF-β1-induced EMT, and only CD44v3,8-10 induces the transcription of vimentin mediated by the EMT transcription factor Slug. In primary tumor specimens obtained from patients with gastric cancer, CD44-containing variant exon 9 (CD44v9) expression and EMT features [E-cadherin(-)vimentin(+)] were significantly correlated, and EMT features in the cells expressing CD44v9 were associated with tumor invasion depth, lymph node metastasis, and pStage, which indicate invasive and metastatic properties, and poor prognosis. These results indicate that certain CD44v isoforms promote tumor cell motility and metastasis in gastric cancer in association with EMT features, and CD44v3,8-10 may contribute to these clinical characteristics.

Several studies have reported the efficacy of resection for recurrent lesions. However, they involved a limited number of subjects. This study aimed to identify a subset of patients who benefit from surgical resection of recurrent lesions after curative esophagectomy for esophageal squamous cell carcinoma.

Most small renal cell carcinomas (small RCCs) will remain indolent after detection, but some stage I RCCs still metastasize. There are no risk-stratification imaging factors that could be used to identify poor-prognosis patients based on genomic profiling. Here, we evaluated the relationships between imaging parameters and RNA expressions in small RCC and attempted to identify imaging factors that could be used as effective biomarkers.

ARID1A is a component of the SWI/SNF complex, which controls the accessibility of proteins to DNA. ARID1A mutations are frequently observed in colorectal cancers (CRCs) and have been reported to be associated with high mutational burden and tumor PD-L1 expression in vitro.

Signal regulatory protein alpha (SIRPα) is a type I transmembrane protein that inhibits macrophage phagocytosis of tumor cells upon interaction with CD47, and the CD47-SIRPα pathway acts as an immune checkpoint factor in cancers. This study aims to clarify the clinical significance of SIRPα expression in esophageal squamous cell carcinoma (ESCC). First, we assessed SIRPα expression using RNA sequencing data of 95 ESCC tissues from The Cancer Genome Atlas (TCGA) and immunohistochemical analytic data from our cohort of 131 patients with ESCC. Next, we investigated the correlation of SIRPα expression with clinicopathological factors, patient survival, infiltration of tumor immune cells, and expression of programmed cell death-ligand 1 (PD-L1). Overall survival was significantly poorer with high SIRPα expression than with low expression in both TCGA and our patient cohort (P < .001 and P = .027, respectively). High SIRPα expression was associated with greater depth of tumor invasion (P = .0017). Expression of SIRPα was also significantly correlated with the tumor infiltration of M1 macrophages, M2 macrophages, CD8+ T cells, and PD-L1 expression (P < .001, P < .001, P = .03, and P < .001, respectively). Moreover, patients with SIRPα/PD-L1 coexpression tended to have a worse prognosis than patients with expression of either protein alone or neither. Taken together, SIRPα indicates poor prognosis in ESCC, possibly through inhibiting macrophage phagocytosis of tumor cells and inducing suppression of antitumor immunity. Signal regulatory protein alpha should be considered as a potential therapeutic target in ESCC, especially if combined with PD-1-PD-L1 blockade.

We evaluated the expression of the androgen receptor (AR) to determine its significance in breast cancer. AR expression levels were analyzed in 250 invasive breast cancers by immunohistochemistry and any association with the clinicopathological features was evaluated. AR expression was higher in estrogen receptor (ER)-positive cases than in ER-negative cases (P < 0.0001). AR expression was associated with ER level, and it increased with age in ER-positive cases. The cut-off value was determined to be 75% (Cancer Res. 2009;69:6131-6140), and AR expression was considered to be high in 155 (62%) cases. High AR expression significantly correlated with lower nuclear grade (P < 0.0001), ER and progesterone receptor (PR) positivity (P < 0.0001 and P = 0.0022), HER2 negativity (P = 0.0113), lower Ki67 index (P < 0.0001) and a longer disease-free survival (DFS) and distant metastasis-free survival (DMFS) (P = 0.0003 and 0.0107). This association between a high AR expression and a good DFS and DMFS was significant for ER-positive tumors (P < 0.0001 and P = 0.0018); however, no association existed between AR expression and prognosis for ER-negative tumors. In patients ≤51 years old, a high AR expression level significantly correlated with a better prognosis, but this was not significant in patients who were 50 or younger. Multivariate Cox hazard analyses revealed AR expression to be independently associated with a good prognosis in overall patients (HR 0.46, P = 0.0052) and in the ER-positive cohort (HR 0.34, P = 0.0009). AR expression is associated with a less aggressive phenotype and a good prognosis in patients with ER-positive breast cancer. This is considered to be a specific phenomenon for postmenopausal breast cancer patients.

Hepatic iron overload is a risk factor for progression of hepatocellular carcinoma (HCC), although the molecular mechanisms underlying this association have remained unclear. We now show that the iron-sensing ubiquitin ligase FBXL5 is a previously unrecognized oncosuppressor in liver carcinogenesis in mice. Hepatocellular iron overload elicited by FBXL5 ablation gave rise to oxidative stress, tissue damage, inflammation, and compensatory proliferation of hepatocytes and to consequent promotion of liver carcinogenesis induced by exposure to a chemical carcinogen. The tumor-promoting outcome of FBXL5 deficiency in the liver was also found to be effective in a model of virus-induced HCC. FBXL5-deficient mice thus constitute the first genetically engineered mouse model of liver carcinogenesis promoted by iron overload. In addition, dysregulation of FBXL5-mediated cellular iron homeostasis was found to be associated with poor prognosis in human HCC, suggesting that FBXL5 plays a key role in defense against hepatocarcinogenesis.