PKCλ/ι inhibition activates an ULK2-mediated interferon response to repress tumorigenesis.

The interferon (IFN) pathway is critical for cytotoxic T cell activation, which is central to tumor immunosurveillance and successful immunotherapy. We demonstrate here that PKCλ/ι inactivation results in the hyper-stimulation of the IFN cascade and the enhanced recruitment of CD8+ T cells that impaired the growth of intestinal tumors. PKCλ/ι directly phosphorylates and represses the activity of ULK2, promoting its degradation through an endosomal microautophagy-driven ubiquitin-dependent mechanism. Loss of PKCλ/ι results in increased levels of enzymatically active ULK2, which, by direct phosphorylation, activates TBK1 to foster the activation of the STING-mediated IFN response. PKCλ/ι inactivation also triggers autophagy, which prevents STING degradation by chaperone-mediated autophagy. Thus, PKCλ/ι is a hub regulating the IFN pathway and three autophagic mechanisms that serve to maintain its homeostatic control. Importantly, single-cell multiplex imaging and bioinformatics analysis demonstrated that low PKCλ/ι levels correlate with enhanced IFN signaling and good prognosis in colorectal cancer patients.

Trophoblast cell surface antigen-2 phosphorylation triggered by binding of galectin-3 drives metastasis through down-regulation of E-cadherin.

The expression of trophoblast cell surface antigen-2 (Trop-2) is enhanced in many tumor tissues and is correlated with increased malignancy and poor survival of patients with cancer. Previously, we demonstrated that the Ser-322 residue of Trop-2 is phosphorylated by protein kinase Cα (PKCα) and PKCδ. Here, we demonstrate that phosphomimetic Trop-2 expressing cells have markedly decreased E-cadherin mRNA and protein levels. Consistently, mRNA and protein of the E-cadherin-repressing transcription factors zinc finger E-Box binding homeobox 1 (ZEB1) were elevated, suggesting transcriptional regulation of E-cadherin expression. The binding of galectin-3 to Trop-2 enhanced the phosphorylation and subsequent cleavage of Trop-2, followed by intracellular signaling by the resultant C-terminal fragment. Binding of ß-catenin/transcription factor 4 (TCF4) along with the C-terminal fragment of Trop-2 to the ZEB1 promoter upregulated ZEB1 expression. Of note, siRNA-mediated knockdown of ß-catenin and TCF4 increased the expression of E-cadherin through ZEB1 downregulation. Knockdown of Trop-2 in MCF-7 cells and DU145 cells resulted in downregulation of ZEB1 and subsequent upregulation of E-cadherin. Furthermore, wild-type and phosphomimetic Trop-2 but not phosphorylation-blocked Trop-2 were detected in the liver and/or lung of some nude mice bearing primary tumors inoculated intraperitoneally or subcutaneously with wild-type or mutated Trop-2 expressing cells, suggesting that Trop-2 phosphorylation, plays an important role in tumor cell mobility in vivo, too. Together with our previous finding of Trop-2 dependent regulation of claudin-7, we suggest that the Trop-2-mediated cascade involves concurrent derangement of both tight and adherence junctions, which may drive metastasis of epithelial tumor cells.

Clinical practice guidelines for molecular tumor marker, 2nd edition review part 2.

In recent years, rapid advancement in gene/protein analysis technology has resulted in target molecule identification that may be useful in cancer treatment. Therefore, "Clinical Practice Guidelines for Molecular Tumor Marker, Second Edition" was published in Japan in September 2021. These guidelines were established to align the clinical usefulness of external diagnostic products with the evaluation criteria of the Pharmaceuticals and Medical Devices Agency. The guidelines were scoped for each tumor, and a clinical questionnaire was developed based on a serious clinical problem. This guideline was based on a careful review of the evidence obtained through a literature search, and recommendations were identified following the recommended grades of the Medical Information Network Distribution Services (Minds). Therefore, this guideline can be a tool for cancer treatment in clinical practice. We have already reported the review portion of "Clinical Practice Guidelines for Molecular Tumor Marker, Second Edition" as Part 1. Here, we present the English version of each part of the Clinical Practice Guidelines for Molecular Tumor Marker, Second Edition.

Bioinformatics Analysis and Validation of Potential Markers Associated with Prediction and Prognosis of Gastric Cancer.

Gastric cancer (GC) is one of the most common cancers worldwide. Most patients are diagnosed at the progressive stage of the disease, and current anticancer drug advancements are still lacking. Therefore, it is crucial to find relevant biomarkers with the accurate prediction of prognoses and good predictive accuracy to select appropriate patients with GC. Recent advances in molecular profiling technologies, including genomics, epigenomics, transcriptomics, proteomics, and metabolomics, have enabled the approach of GC biology at multiple levels of omics interaction networks. Systemic biological analyses, such as computational inference of "big data" and advanced bioinformatic approaches, are emerging to identify the key molecular biomarkers of GC, which would benefit targeted therapies. This review summarizes the current status of how bioinformatics analysis contributes to biomarker discovery for prognosis and prediction of therapeutic efficacy in GC based on a search of the medical literature. We highlight emerging individual multi-omics datasets, such as genomics, epigenomics, transcriptomics, proteomics, and metabolomics, for validating putative markers. Finally, we discuss the current challenges and future perspectives to integrate multi-omics analysis for improving biomarker implementation. The practical integration of bioinformatics analysis and multi-omics datasets under complementary computational analysis is having a great impact on the search for predictive and prognostic biomarkers and may lead to an important revolution in treatment.

The heterogeneity of cancer-associated fibroblast subpopulations: Their origins, biomarkers, and roles in the tumor microenvironment.

The prognosis for patients with cancers known for a highly activated stromal reaction, including diffuse-type (scirrhous) gastric cancer, consensus molecular subtype 4 (CMS4) colorectal cancer, and pancreatic ductal adenocarcinoma, is extremely poor. To explore the resistance of conventional therapy for those refractory cancers, detailed classification and investigation of the different subsets of cancer-associated fibroblasts (CAFs) involved are needed. Recent studies with a single-cell transcriptomics strategy (single-cell RNA-seq) have demonstrated that CAF subpopulations contain different origins and marker proteins with the capacity to either promote or suppress cancer progression. Through multiple signaling pathways, CAFs can promote tumor growth, metastasis, and angiogenesis with extracellular matrix (ECM) remodeling; they can also interact with tumor-infiltrating immune cells and modulate the antitumor immunological state in the tumor microenvironment (TME). Here, we review the recent literature on the various subpopulations of CAFs to improve our understanding of the cell-cell interactions in the TME and highlight future avenues for CAF-targeted therapy.

IL-1ß derived from mixed-polarized macrophages activates fibroblasts and synergistically forms a cancer-promoting microenvironment.

BACKGROUND: Remodeling the tumor microenvironment (TME) to benefit cancer cells is crucial for tumor progression. Although diffuse-type gastric cancer (DGC) preferentially interacts with the TME, the precise mechanism of the complicated network remains unknown. This study aimed to investigate the mutual activation mechanism underlying DGC progression. METHODS: Mass cytometry analysis of co-cultured macrophages, noncancerous fibroblasts (NFs), and DGC cells was performed. RNA sequencing was applied to examine gene expression in fibroblasts. DGC cells were treated with cytokines to examine their effect on characteristic changes. The TCGA and Kumamoto University cohorts were used to evaluate the clinical relevance of the in vitro findings. RESULTS: Cohort analysis revealed that DGC patients had a poor prognosis. The fibroblasts and macrophages interacted with DGC cells to form a cell cluster in the invasive front of DGC tissue. The original 3D triple co-culture system determined the promotional effects of nonmalignant cells on DGC invasive growth. We notably identified a mixed-polarized macrophage cell type with M1/M2 cell surface markers in a triple co-culture system. IL-1ß from mixed-polarized macrophages induced the conversion of NFs to cancer-associated fibroblast-like (CAF-like) cells, promoting the malignant phenotype of DGC cells by inducing the secretion of IL-6, IL-24, and leukemia inhibitory factor (LIF). Moreover, IL-6 and colony stimulating factor 2 (GM-CSF) cooperated to maintain the stable state of mixed-polarized macrophages. Finally, we found that mixed-polarized macrophages were frequently detected in DGC tissues. CONCLUSION: These findings demonstrated that mixed-polarized macrophages exist as a novel subtype through the reciprocal interaction between DGC cells and nonmalignant cells.

The Cancer Cachexia Index Can Be Used to Prognostically Predict Patients with Gastric Cancer Undergoing Gastrectomy.

INTRODUCTION: Cancer cachexia occurs in cancer patients more frequently as the cancer progresses, with a negative impact on treatment outcomes. In this study, we sought to clarify the clinical impact of a cancer cachexia index (CXI) in patients with gastric cancer (GC) undergoing gastrectomy. METHODS: Between January 2013 and December 2018, we reviewed data from 556 patients treated for GC at our hospital. CXI was calculated using skeletal muscle index (SMI), serum albumin, and neutrophil-lymphocyte ratios (NLR). Patients were divided into high (n = 414) or low CXI (n = 142) groups. We investigated the clinical impact of CXI in patients with GC undergoing gastrectomy. RESULTS: Multivariate analyses of 5-year overall survival (OS) and cancer-specific survival (CSS) rates indicated that a low CXI was independently associated with unfavorable outcomes for patients with GC. In multivariate analyses, SMI was independent predictor of OS but not CSS. NLR was not an independent predictor of either OS or CSS. Complication incidences (≥ Clavien Dindo 3) were non-significantly higher in the low (vs. high) CXI group. CONCLUSION: CXI was a more valuable prognostic biomarker when compared with SMI or NLR in GC patients undergoing gastrectomy. We suggest that patients with low CXI values should be given more comprehensive treatment, including exercise and nutritional therapy to improve clinical outcomes.

[The Role of Cancer-Associated Fibroblasts in Modulating Tumor Immunity in Colorectal Cancer].

Cancer-associated fibroblasts(CAFs)remodel the extracellular matrix(ECM)and shape the tumor microenvironment (TME), resulting in immune escape and the promotion of tumor metastasis. Using an orthotopic tumor model of colorectal cancers(CRCs)in mice, we demonstrated that the single-cell RNA sequencing of orthotopic rectal tumors identified a subpopulation of CAFs that modulate the immune response. In this review, we report that understanding the role of CAFs in the TME concerning tumor immunity may lead to future avenues for CAF-targeted therapy.

Interleukin-8 produced from cancer-associated fibroblasts suppresses proliferation of the OCUCh-LM1 cancer cell line.

BACKGROUND: Cancer-associated fibroblasts (CAFs) play an important role in cancer growth by interacting with cancer cells, but their effects differ depending on the type of cancer. This study investigated the role of CAFs in biliary tract cancers (BTCs), compared with pancreatic ductal adenocarcinoma (PDAC) as a comparison cohort. METHODS: We retrospectively evaluated alpha-smooth muscle actin (αSMA) expression in CAFs from 114 cases of PDAC and 154 cases of BTCs who underwent surgical treatment at our institution from 1996 to 2017. CAFs were isolated from resected specimens of BTC and PDAC, and tested for the effects of their supernatants and cytokines on cancer cell proliferation. RESULTS: PDAC patients with positive αSMA expression showed significantly shorter overall survival and recurrence-free survival than αSMA-negative patients (p = 0.003, p = 0.009, respectively). BTC patients with positive αSMA expression showed better recurrence-free survival than αSMA-negative patients (p = 0.03). CAF-conditioned medium suppressed the proliferation of cancer cells for only OCUCh-LM1 cells and not PDAC cells. Blockage of Interleukin-8 (IL-8) or its receptor C-X-C motif chemokine receptor 2 (CXCR2) by antibodies canceled the suppressive effect of the IL-8. CONCLUSIONS: CAFs are a good prognostic factor in BTC, but not for PDAC. Moreover, CAF-produced Interleukin-8 suppresses the proliferation of OCUCh-LM1 cell lines.

Significance of tumor heterogeneity of p-Smad2 and c-Met in HER2-positive gastric carcinoma with lymph node metastasis.

BACKGROUND: Tumor heterogeneity has frequently been observed in gastric cancer (GC), but the correlation between patients' clinico-pathologic features and the tumoral heterogeneity of GC-associated molecules is unclear. We investigated the correlation between lymph node metastasis and the intra-tumoral heterogeneity of driver molecules in GC. MATERIALS AND METHODS: We retrospectively analyzed the cases of 504 patients who underwent a gastrectomy at the Department of Gastroenterological Surgery, Osaka Metropolitan University and 389 cases drawn from The Cancer Genome Atlas (TCGA) data. We performed a clustering analysis based on eight cancer-associated molecules including HER2, c-Met, and p-Smad2 using the protein expression revealed by our immunohistochemical study of the patients' and TCGA cases. We determined the correlations between HER2 expression and the other molecules based on the degree of lymph node metastasis. RESULTS: Immunohistochemical staining data showed that a 43 of the 504 patients with GC (8.5%) were HER2-positive. In the HER2-positive cases, the expressions of c-Met and p-Smad2 were increased in accord with the lymph-node metastatic level. The overall survival of the HER2-positive GC patients with both p-Smad2 and c-Met expression was significantly (p = 0.030) poorer than that of the patients with p-Smad2-negative and/or c-Met-negative expression. The results of the TCGA data analysis revealed that 58 of the 389 GC cases (14.9%) were ERBB2-positive. MET expression was more frequent in the N1 metastasis group than the N0 group. In the high lymph-node metastasis (N2 and N3) group, SMAD2 expression was more frequent, as was ERBB2 and MET expression. CONCLUSION: p-Smad2 and c-Met signaling might play important roles in lymph node metastasis in HER2-positive GC.

Lipocalin-2 negatively regulates epithelial-mesenchymal transition through matrix metalloprotease-2 downregulation in gastric cancer.

BACKGROUND: Although the role of Lipocalin-2 (LCN2) in cancer development has been focused on recent studies, the molecular mechanisms and clinical relevance of LCN2 in gastric cancer (GC) still remain unclear. METHODS: Transcriptome analysis of GC samples from public human data was performed according to Lauren's classification and molecular classification. In vitro, Western blotting, RT-PCR, wound healing assay and invasion assay were performed to reveal the function and mechanisms of LCN2 in cell proliferation, migration and invasion using LCN2 knockdown cells. Gene set enrichment analysis (GSEA) of GC samples from public human data was analyzed according to LCN2 expression. The clinical significance of LCN2 expression was investigated in GC patients from public data and our hospital. RESULTS: LCN2 was downregulated in diffuse-type GC, as well as in Epithelial-Mesenchymal Transition (EMT) type GC. LCN2 downregulation significantly promoted proliferation, invasion and migration of GC cells. The molecular mechanisms of LCN2 downregulation contribute to Matrix Metalloproteinases-2 (MMP2) stimulation which enhances EMT signaling in GC cells. GSEA revealed that LCN2 downregulation in human samples was involved in EMT signaling. Low LCN2 protein and mRNA levels were significantly associated with poor prognosis in patients with GC. LCN2 mRNA level was an independent prognostic factor for overall survival in GC patients. CONCLUSIONS: LCN2 has a critical role in EMT signaling via MMP2 activity during GC progression. Thus, LCN2 might be a promising therapeutic target to revert EMT signaling in GC patients with poor outcomes.

Expression of asporin reprograms cancer cells to acquire resistance to oxidative stress.

Asporin (ASPN), a small leucine-rich proteoglycan expressed predominantly by cancer associated fibroblasts (CAFs), plays a pivotal role in tumor progression. ASPN is also expressed by some cancer cells, but its biological significance is unclear. Here, we investigated the effects of ASPN expression in gastric cancer cells. Overexpression of ASPN in 2 gastric cancer cell lines, HSC-43 and 44As3, led to increased migration and invasion capacity, accompanied by induction of CD44 expression and activation of Rac1 and MMP9. ASPN expression increased resistance of HSC-43 cells to oxidative stress by reducing the amount of mitochondrial reactive oxygen species. ASPN induced expression of the transcription factor HIF1α and upregulated lactate dehydrogenase A (LDHA) and PDH-E1α, suggesting that ASPN reprograms HSC-43 cells to undergo anaerobic glycolysis and suppresses ROS generation in mitochondria, which has been observed in another cell line HSC-44PE. By contrast, 44As3 cells expressed high levels of HIF1α in response to oxidant stress and escaped apoptosis regardless of ASPN expression. Examination of xenografts in the gastric wall of ASPN-/- mice revealed that growth of HSC-43 tumors with increased micro blood vessel density was significantly accelerated by ASPN; however, ASPN increased the invasion depth of both HSC-43 and 44As3 tumors. These results suggest that ASPN has 2 distinct effects on cancer cells: HIF1α-mediated resistance to oxidative stress via reprogramming of glucose metabolism, and activation of CD44-Rac1 and MMP9 to promote cell migration and invasion. Therefore, ASPN may be a new therapeutic target in tumor fibroblasts and cancer cells in some gastric carcinomas.

Asporin Expression on Stromal Cells and/or Cancer Cells Might Be A Useful Prognostic Marker in Patients with Diffuse-Type Gastric Cancer.

BACKGROUND: Asporin (ASPN), a member of the proteoglycan family, has been shown to have a close correlation with cancer progression. It is not known whether ASPN is an oncogenic driver or a tumor suppressor in human gastric cancer. We sought herein to determine the relationship between ASPN expression and clinicopathological features of gastric cancer. PATIENTS AND METHODS: A total of 296 gastric cancer patients (diffuse type, n = 144; intestinal type, n = 152) were enrolled. The ASPN expression level in each case was analyzed by immunohistochemistry. RESULTS: ASPN was mainly found on stromal cells, especially on fibroblasts in tumor stroma, i.e., cancer-associated fibroblasts. The ASPN expression on either cancer cells or stromal cells was significantly high in macroscopic scirrhous-type tumors (p < 0.001) and histologically abundant stroma-type tumors (p < 0.001). Interestingly, a Kaplan-Meier survival curve of the 144 cases of diffuse-type gastric cancer revealed a significantly poorer prognosis in patients with ASPN-positive expression (p = 0.043; log rank) compared to those with ASPN-negative expression, but the prognoses were not significantly different in these subgroups of the 152 cases of intestinal-type gastric cancer. A multivariate analysis with respect to overall survival showed that ASPN expression on stromal cells and/or cancer cells was significantly correlated with overall survival in patients with diffuse-type gastric cancer (p = 0.041). CONCLUSION: In gastric cancer, ASPN was expressed mainly on stromal cells and partially on cancer cells. ASPN expression on stromal cells and/or cancer cells might be a useful prognostic marker in patients with diffuse-type gastric cancer.

Preoperative C-reactive protein to albumin ratio predicts anastomotic leakage after esophagectomy for thoracic esophageal cancer: a single-center retrospective cohort study.

BACKGROUND: Postoperative anastomotic leakage (AL) is associated with not only prolonged hospital stay and increased medical costs, but also poor prognosis in esophageal cancer. Several studies have addressed the utility of various inflammation-based and/or nutritional markers as predictors for postoperative complications. However, none have been documented as specific predictors for AL in esophageal cancer. We aimed to identify predictors of AL after esophagectomy for thoracic esophageal cancer, focusing on preoperative inflammation-based and/or nutritional markers. METHODS: We retrospectively analyzed 295 patients who underwent radical esophagectomy for thoracic esophageal squamous cell carcinoma between June 2007 and July 2020. As inflammation-based and/or nutritional markers, Onodera prognostic nutritional index, C-reactive protein (CRP)-to-albumin ratio (CAR) and modified Glasgow prognostic score were investigated. Optimal cut-off values of inflammation-based and/or nutritional markers for AL were determined by receiver operating characteristic curves. Predictors for AL were analyzed by logistic regression modeling. RESULTS: AL was observed in 34 patients (11.5%). In univariate analyses, preoperative body mass index (≥ 22.1 kg/m2), serum albumin level (≤ 3.8 g/dL), serum CRP level (≥ 0.06 mg/dL), CAR (≥ 0.0139), operation time (> 565 min) and blood loss (≥ 480 mL) were identified as predictors of AL. Multivariate analyses revealed higher preoperative CAR (≥ 0.0139) as an independent predictor of AL (p = 0.048, odds ratio = 3.02, 95% confidence interval 1.01-9.06). CONCLUSION: Preoperative CAR may provide a useful predictor of AL after esophagectomy for thoracic esophageal squamous cell carcinoma.

[A Case of Hyperammonemic Encephalopathy following mFOLFOX6 plus Panitumumab Therapy for Rectal Cancer].

An 80-year-old man underwent laparoscopic rectal high anterior resection with perineal dissemination for the management of RS rectal cancer. Following the diagnosis of RS rectal cancer with muc, pT4a, N3(14/15), M1c, P1, pStage Ⅳc, RAS/BRAF: wild type, treatment was initiated with mFOLFOX6 plus panitumumab(Pmab). Laboratory examination on admission revealed mild renal dysfunction(Cr 1.45 mg/dL). The patient became confused on day 3 of chemotherapy(JCS Ⅲ-200). Furthermore, laboratory findings revealed a serum ammonia level of 338µg/dL. He was diagnosed with 5-FU- induced hyperammonemic encephalopathy. Discontinuation of high-dose 5-FU and branched-chain amino acid solutions improved his mental status and decreased serum ammonia levels. We switched his chemotherapy regime to CPT-11 plus Pmab, but it was discontinued after 1 course on his request.

[Effect of Upfront Dose Reduction in the First Cycle of Chemotherapy for Unresectable/Recurrent Gastric Cancers in Patients Aged Over 80 Years].

Chemotherapy for elderly patients requires ingenuity in treatment to mitigate its high risk. Therefore, we investigated an upfront dose reduction in the first cycle of chemotherapy for unresectable/recurrent gastric cancers in patients over 80 years old. We examined 6 patients over 80 years old, who underwent S-1 plus L-OHP therapy(SOX)for unresectable/recurrent gastric cancer in our department between January 2020 and January 2021. There were no adverse events over Grade 3 in the upfront dose reduction group(U group), while 1 case(50.0%)in the normal dose group(N group)experienced an adverse event over Grade 3. Moreover, only the U group continued treatment for 4 or more courses, whereas none from the N group did. Partial response(PR)was achieved as a therapeutic effect in 3 patients of the U group. Only 2 cases of the U group advanced to the second-line regimen and both were able to transition to the third-line regimen. However, none were able to even transition to the second-line regimen in the N group. Therefore, it was suggested that by reducing the dose of chemotherapy from the first cycle for elderly patients over 80 years old, the incidence of adverse events can be kept low, which makes it possible to continue long-term chemotherapy.

The duration of systemic inflammatory response syndrome is a reliable indicator of long-term survival after curative esophagectomy for esophageal squamous cell carcinoma.

BACKGROUND: We focused on the Systemic Inflammatory Response Syndrome (SIRS) duration after surgery for esophageal squamous cell carcinoma (ESCC) as the prognostic marker. METHODS: We enrolled a total of 222 patients with local ESCC, who underwent curative esophagectomy between 2005 and 2015. SIRS was diagnosed according to the criteria as a condition involving two or more of the following factors after surgery: (a) body temperature of > 38 °C or < 36 °C; (b) heart rate > 90 beats/min; (c) respiratory rate > 20 breaths/min (d) WBC count > 12,000 or < 4000 cells/mm3. We defined SIRS duration as the total sum of the days defined as SIRS conditions during 7 days after surgery. The SIRS duration was analyzed by Cox hazards modeling to determine the independent prognostic factors for overall survival (OS) and Cancer-specific survival (CSS). RESULTS: The cutoff point of SIRS duration was determined to be set at 5.0 days according to the receiver operating characteristic (ROC) curve, which was plotted using 5-year OS as the endpoint. Of the 222 patients, 165 (74.4%) and 57 (25.6%) were classified as having short (< 5.0) and long (≥ 5.0) SIRS, respectively. The long SIRS was significantly associated with postoperative pneumonia (Hazard Ratio (HR):9.07; P < 0.01), great amount of blood loss during surgery (HR: 2.20: P = 0.04), preoperative high CRP value (HR: 2.45: P = 0.04) and preoperative low albumin (HR: 2.79: P = 0.03) by logistic-regression multivariate analysis. Cox Hazard Multivariate analyses revealed that long SIRS was a worse prognostic factor for OS (HR: 2.36; 95% Confidence Interval (CI):1.34-4.20, P < 0.01) and CSS (HR: 2.07; 95% CI:1.06-4.06, P = 0.03), while postoperative pneumonia and postoperative high CRP value were not worse prognostic factors for OS and CSS. CONCLUSION: SIRS duration is a more reliable prognostic marker than the development of pneumonia and high postoperative CRP value after surgery for ESCC. The surgeons should aim to reduce the SIRS duration to improve the prognosis of ESCC patients.

Serine threonine kinase 11/liver kinase B1 mutation in sporadic scirrhous-type gastric cancer cells.

Scirrhous-type gastric carcinoma (SGC), which is characterized by the rapid proliferation of cancer cells accompanied by extensive fibrosis, shows extremely poor survival. A reason for the poor prognosis of SGC is that the driver gene responsible for SGC has not been identified. To identify the characteristic driver gene of SGC, we examined the genomic landscape of six human SGC cell lines of OCUM-1, OCUM-2M, OCUM-8, OCUM-9, OCUM-12 and OCUM-14, using multiplex gene panel testing by next-generation sequencing. In this study, the non-synonymous mutations of serine threonine kinase 11/liver kinase B1 (STK11/LKB1) gene were detected in OCUM-12, OCUM-2M and OCUM-14 among the six SGC cell lines. Capillary sequencing analysis confirmed the non-sense or missense mutation of STK11/LKB1 in the three cell lines. Western blot analysis showed that LKB1 expression was decreased in OCUM-12 cells and OCUM-14 cells harboring STK11/LKB1 mutation. The mammalian target of rapamycin (mTOR) inhibitor significantly inhibited the proliferation of OCUM-12 and OCUM-14 cells. The correlations between STK11/LKB1 expression and clinicopathologic features of gastric cancer were examined using 708 primary gastric carcinomas by immunochemical study. The low STK11/LKB1 expression group was significantly associated with SGC, high invasion depth and frequent nodal involvement, in compared with the high STK11/LKB1 expression group. Collectively, our study demonstrated that STK11/LKB1 mutation might be responsible for the progression of SGC, and suggested that mTOR signaling by STK11/LKB1 mutation might be one of therapeutic targets for patients with SGC.

Circulating tumor cells with FGFR2 expression might be useful to identify patients with existing FGFR2-overexpressing tumor.

Fibroblast growth factor receptor (FGFR) is associated with proliferation, migration, and angiogenesis of carcinomas, and FGFR signaling inhibitors are considered a key drug for the treatment of solid tumors with FGFR overexpression. Amplification of FGFR2 is reportedly identified in 3%-10% of gastric cancers (GCs). The aim of this study is to clarify whether the identification of the circulating tumor cells (CTCs) with FGFR2 overexpression is useful to detect patients with FGFR2-overexpressing GC. One hundred GC patients who underwent gastrectomy were enrolled. A total volume of 8 mL of peripheral blood was collected from each patient just before gastrectomy, and mononuclear cells were enriched by Ficol density gradient centrifugation. These cells were immunostained with PI/CD45/EpCAM/FGFR2. The number of CTCs with FGFR2 expression in each sample was enumerated by FACScan. The FGFR2 expression level of the resected primary tumor was assessed by immunohistochemistry. The number of FGFR2-positive CTCs in the GC patients' peripheral blood was significantly correlated with the FGFR2 expression level of the primary GC. The relapse-free survival of the patients with FGFR2-positive CTCs (≥5 cells/10 mL blood) was significantly poorer (P = .018, log-rank) than that of the patients without FGFR2-positive CTCs (<5 cell/10 mL blood). These findings suggested that the determination of FGFR2-positive CTCs might help identify an existing tumor with FGFR2 overexpression.

Clinical significance of prognostic inflammation-based and/or nutritional markers in patients with stage III gastric cancer.

BACKGROUND: Although many studies have identified several inflammation-based and/or nutritional markers with prognostic value for patients with various types of cancer, the optimal markers and cut-off values for these markers remain obscure. Therefore, this retrospective study aimed to identify optimal markers and their cutoffs. METHODS: We compared prognostic values among established preoperative inflammation-based and/or nutritional markers in 225 patients who underwent R0 resection for stage III gastric cancer. Inflammation-based and/or nutritional markers comprised C-reactive protein to albumin ratio (CAR), neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), prognostic nutritional index (PNI), Glasgow prognostic score (GPS), and prognostic index (PI). Time-dependent receiver operating characteristic curves were analyzed to assess predictive ability and to determine the optimal cut-off values. Prognostic factors predicting overall survival (OS) and cancer specific survival (CSS) were analyzed using Cox proportional hazards models. RESULTS: Multivariate analyses revealed that CAR and PLR cut-off values of 0.47 and 172, respectively, were independent prognostic factors for overall survival (OS) (HR, 2.257; 95% CI, 1.180-4.319; p = 0.014 and HR, 1.478; 95% CI, 1.025-2.133; p = 0.037, respectively) and cancer-specific survival (CSS) (HR, 2.771; 95% CI, 1.398-5.493; p = 0.004 and HR, 1.552; 95% CI, 1.029-2.341; p = 0.036, respectively). These results were different from those we previously reported in patients with stage II. CONCLUSIONS: Among inflammation-based and/or nutritional markers, CAR and PLR were independent prognostic factors of OS and CSS in patients with stage III gastric cancer. The optimal markers and their cut-off values should be determined in specific populations.