Metabolic activity by 18F-FDG-PET/CT is predictive of early response after nivolumab in previously treated NSCLC.

BACKGROUND: Nivolumab, an anti-programmed death-1 (PD-1) antibody, is administered in patients with previously treated non-small cell lung cancer. However, little is known about the established biomarker predicting the efficacy of nivolumab. Here, we conducted a preliminary study to investigate whether 18F-FDG-PET/CT could predict the therapeutic response of nivolumab at the early phase. METHODS: Twenty-four patients were enrolled in this study. 18F-FDG-PET/CT was carried out before and 1 month after nivolumab therapy. SUVmax, metabolic tumour volume (MTV), and total lesion glycolysis (TLG) were calculated. Immunohistochemical analysis of PD-L1 expression and tumour-infiltrating lymphocytes was conducted. RESULTS: Among all patients, a partial metabolic response to nivolumab was observed in 29% on SUVmax, 25% on MTV, and 33% on TLG, whereas seven (29%) patients achieved a partial response (PR) based on RECIST v1.1. The predictive probability of PR (100% vs. 29%, p = 0.021) and progressive disease (100% vs. 22.2%, p = 0.002) at 1 month after nivolumab initiation was significantly higher in 18F-FDG on PET/CT than in CT scans. Multivariate analysis confirmed that 18F-FDG uptake after administration of nivolumab was an independent prognostic factor. PD-L1 expression and nivolumab plasma concentration could not precisely predict the early therapeutic efficacy of nivolumab. CONCLUSION: Metabolic response by 18F-FDG was effective in predicting efficacy and survival at 1 month after nivolumab treatment.

Elevated expression of ΔNp63 in advanced esophageal squamous cell carcinoma.

This study aims to explore the expression level of ΔNp63 in esophageal squamous cell carcinoma (ESCC). To investigate the association between ΔNp63 (p40) expression and ESCC biology, we compared the levels of ΔNp63 expression in normal and tumor tissues, with a specific focus on the diagnostic value of ΔNp63 in ESCC. We analyzed 160 consecutive patients with ESCC who underwent surgical resection without neoadjuvant chemotherapy at Gunma University Hospital (Maebashi, Japan) between September 2000 and January 2010. The clinicopathological characteristics and survival of patients were subclassified based on the expression of ΔNp63 as determined by immunohistochemistry, indicating that ΔNp63 was highly expressed in 75.6% (121/160) of ESCC patients. Clinicopathological analysis of ΔNp63 expression showed that ΔNp63-positive tumors significantly correlated with two important clinical parameters: T factor (P = 0.0316) and venous invasion (P = 0.0195). The 5-year overall survival rates of advanced ESCC patients with positive and negative expression of ΔNp63 were 35.6% and 71.7%, respectively. Multivariate analysis revealed that the expression of ΔNp63 was identified as an independent prognostic factor (P = 0.0049) in advanced ESCC. In line with this, ΔNp63α-transduced ESCC cell lines increased tumor growth in a soft agar colony formation assay. We report here for the first time that ΔNp63 expression increases the oncogenic potential of ESCC and is an independent marker for predicting poor outcome in advanced ESCC. Our findings suggest that ΔNp63 could serve as a new diagnostic marker for ESCC and might be a relevant therapeutic target for the treatment of patients with this disease.

High STMN1 level is associated with chemo-resistance and poor prognosis in gastric cancer patients.

BACKGROUND: Stathmin1 (STMN1) is a cytosolic phosphoprotein that regulates cellular microtubule dynamics and is known to have oncogenic activity. Despite several reports, its roles in gastric cancer (GC) remain unclear owing to a lack of analyses of highly metastatic cases. This study aimed to investigate STMN1 as a prognostic and predictive indicator of response to paclitaxel therapy in patients with GC, including inoperable cases. METHODS: Immunohistochemical analysis of STMN1 was performed on both operable (n=95) and inoperable GC (n=61) samples. The roles of STMN1 in cancer cell proliferation and sensitivity to a microtubule-targeting drug, paclitaxel, were confirmed by knockdown experiments using GC cell lines. RESULTS: Multivariate and Kaplan-Meier analyses demonstrated that high STMN1 was predictive of poor prognosis in both the groups. In the operable cohort, STMN1 expression correlated with cancer curability, recurrence, and resistance to adjuvant therapy. A correlation with paclitaxel resistance was observed in inoperable cases. Knockdown of STMN1 in GC cell lines inhibited proliferation and sensitised the cells to paclitaxel by enhancing apoptosis. CONCLUSIONS: STMN1 is a possible biomarker for paclitaxel sensitivity and poor prognosis in GC and could be a novel therapeutic target in metastatic GC.

High STMN1 Expression is Associated with Cancer Progression and Chemo-Resistance in Lung Squamous Cell Carcinoma.

BACKGROUND: Known as a microtubule-destabilizing protein, STMN1 (gene symbol: STMN1) regulates the dynamics of microtubules, cell cycle progress, and chemo-resistance against taxane agents. It is highly expressed in various human cancers and involved in cancer progression as well as poor prognosis. METHODS: Expression of STMN1 was examined by immunohistochemistry using FFPE tissue sections from 186 patients with lung squamous cell carcinoma (LSCC). Analysis of STMN1 suppression was performed for STMN1 small interfering RNA (siRNA)-transfected LSCC cell lines to determine the change in proliferation, invasive and apoptosis abilities, and paclitaxel sensitivity. RESULTS: The cytoplasmic STMN1 expression in LSCC was higher than in normal tissues. The high expression was significantly associated with vascular invasion (P = 0.0477) and poor prognosis. In addition, the proliferating and invasive abilities were decreased, and the apoptosis ability and paclitaxel sensitivity were increased in STMN1-suppressed LSCC cells compared with control cells. CONCLUSION: The results suggest that STMN1 is a prognostic factor that also is associated with caner progression and chemo-resistance. Therefore, STMN1 could be a predictor for poor prognosis and a potential therapeutic target in LSCC.

High expression of nucleobindin 2 is associated with poor prognosis in gastric cancer.

Nucleobindin 2 has been reported that its high expression is associated with poor outcome and promotes cell migration and lymph node metastasis in breast cancer, colon cancer, and prostate cancer. However, we aimed to investigate the nucleobindin 2 expression in gastric cancer tissues and adjacent non-tumor tissues and its potential relevance to clinicopathological factors and prognosis using immunohistochemical analysis. In our study, nucleobindin 2 level in gastric cancer tissues was higher than in non-tumor tissues. A high expression of nucleobindin 2 is significantly associated with tumor depth, lymph node metastasis, lymphatic invasion, venous invasion, and clinical stage. Furthermore, the expression level of nucleobindin 2 protein was independent predictor of progression-free survival. In summary, nucleobindin 2 might play a crucial role in gastric cancer development and could serve as an independent predictor of prognosis of gastric cancer patients.

Enhanced karyopherin-α2 expression is associated with carcinogenesis in patients with intraductal papillary mucinous neoplasms.

BACKGROUND/OBJECTIVES: Intraductal papillary mucinous neoplasms (IPMN) can become malignant. Karyopherin-α2 (KPNA2) plays a central role in nucleocytoplasmic transport and is associated with various types of cancer. The current study examined pancreatic KPNA2 expression in cancer patients and evaluated its association with clinicopathological factors, cancer cell proliferation. METHODS: KPNA2 expression was investigated by immunohistochemistry in 40 surgically resected IPMN samples and its association with clinicopathological factors and Ki-67 expression were examined. RESULTS: Eighteen IPMN samples (45% of patients) showed positive KPNA2 expression. KPNA2 expression levels in IPMN tissue with invasive carcinoma were significantly higher than those in adjacent normal tissues and in IPMN tissue with low-to high-grade dysplasia. KPNA2 expression correlated with pathological malignancy and Ki-67 labeling index and KPNA2 and Ki-67 expression was co-localized in nuclei. E2F were co-localized with KPNA2 in the IPMN tissues with high expression of KPNA2. KPNA2 expression was enhanced in the invasion front and in proliferating Ki-67-positive cells. In addition, KPNA2 expression in IPMN tissues was associated with older age, dilation of main pancreatic duct diameter, the presence of nodules, and histological type. CONCLUSION: KPNA2 expression is associated with carcinogenesis of IPMN through the adenoma-carcinoma sequence.

Caspase14 expression is associated with triple negative phenotypes and cancer stem cell marker expression in breast cancer patients.

BACKGROUND AND OBJECTIVES: The Caspase14 (CASP14) was reported that the low expression of CASP14 in ovarian cancer and colon cancer was associated with cancer progression, on the other hand, that the CASP14 expression in breast cancer was higher than that of non-cancerous tissues. The purpose of this study is to determine the clinical significance of CASP14 in breast cancer. METHODS: We performed immunohistochemistry for CASP14, ER, PgR, HER2, Ki67, EGFR, CK5/6, CD44, CD24, ALDH1, claudins, and androgen receptor in 222 breast cancer patients including 55 TNBC cases, and evaluated the relationship of CASP14, above-mentioned markers, and prognosis. Using public microarray database of breast cancer, the prognostic value of CASP14 was calculated. RESULTS: High CASP14 expression was significantly associated with TNBC subtype (P = 0.015), nuclear grade (P = 0.006), Ki67, EGFR (P < 0.001, P = 0.016), ALDH1, CD44 and CD24 (P < 0.001, P < 0.001, P = 0.001) in 222 breast cancer cases, and the high expression of claudin1 (P = 0.017), and androgen receptor (P = 0.002) in TNBC cases was related to the high CASP14. According to the public database, survival in the high CASP14 breast cancer patients was shorter than low CASP14 patients. CONCLUSIONS: High CASP14 expression is a marker of breast cancer aggressiveness in association with proliferation, TNBC phenotype, and cancer stemness.

Overexpression of natural killer group 2 member D ligands predicts favorable prognosis in cholangiocarcinoma.

The natural killer group 2 member D (NKG2D) receptor and its ligands are important mediators of immune responses to tumors. NKG2D ligands are overexpressed in several malignant tumor types; however, the prognostic value of these ligands is unclear. Here, we aimed to elucidate the role of NKG2D ligands in extrahepatic cholangiocarcinoma (EHCC). We therefore investigated the expression of the NKG2D receptor and its ligands MHC class I chain-related proteins A and B (MICA/B), unique long 16 binding protein (ULBP) 1, and ULBP2/5/6 in resected specimens from 82 patients with EHCC. All NKG2D ligands were highly expressed in EHCC. High expression of MICA/B or ULBP2/5/6 correlated with overall and disease-free survival. In contrast, high expression of ULBP1 was significantly associated with improved overall survival, but not disease-free survival. Concurrent high expression of multiple NKG2D ligands revealed significantly better overall and disease-free survival than that observed with the overexpression of any one NKG2D ligand. Co-expression of multiple NKG2D ligands was an independent prognostic indicator of improved survival. Furthermore, co-overexpression of multiple NKG2D ligands was significantly correlated with high expression of the NKG2D receptor. Inhibiting interactions between multiple NKG2D ligands and the NKG2D receptor might be a promising approach for controlling cancer progression and improving patient prognosis in EHCC.

High expression of karyopherin-α2 and stathmin 1 is associated with proliferation potency and transformation in the bile duct and gall bladder epithelia in the cases of pancreaticobiliary maljunction.

BACKGROUNDS AND OBJECTIVES: Pancreaticobiliary maljunction (PBM) may be associated with an increased frequency of gall bladder cancer with no bile duct dilation. Karyopherin-α2 (KPNA2) and stathmin 1 (STMN1) were reported to play important roles in carcinogenesis and cancer progression. METHODS: Fifteen patients with PBM who underwent surgical resection between 1999 and 2014 were included in this study. Using immunohistochemistry, we investigated the expression of p53, Ki-67, KPNA2, and STMN1 in normal biliary tract epithelium, hyperplastic epithelium, and cholangiocarcinoma (CC) tissues. RESULTS: Nuclear expression of KPNA2, p53, and Ki-67 expression was detected in hyperplastic epithelium and CC tissues. High KPNA2 expression was significantly associated with gender (P = 0.04), p53 nuclear accumulation (P = 0.00435), and Ki-67 expression (P = 0.0443) in the gall bladder and bile duct of PBM. On the other hand, STMN1 was only expressed in CC tissues and was not observed in normal bile duct and hyperplastic epithelia. CONCLUSIONS: KPNA2 might be a useful marker of hyperplasia, dysplasia, and carcinogenicity in patients with PBM. STMN1 evaluation might be a cancer-specific marker for CC patients with PBM similar as that for other cancers. J. Surg. Oncol. 2016;114:462-468. © 2016 Wiley Periodicals, Inc.

Nuclear PRMT1 expression is associated with poor prognosis and chemosensitivity in gastric cancer patients.

BACKGROUND: Metastatic and refractory gastric cancer (GC) are associated with a poor prognosis; therefore, the identification of prognostic factors and chemosensitivity markers is extremely important. Protein arginine methyltransferase 1 (PRMT1) may play a role in chemosensitivity/apoptosis induction via activation of the tumor suppressor forkhead box O1 (FOXO1). The purpose of this study was to clarify the expression of and relationship between PRMT1 and FOXO1 to evaluate the applicability of PRMT1 as a prognostic marker and a therapeutic tool in GC. METHODS: We investigated the clinical and functional significance of PRMT1 and FOXO1 in 195 clinical GC samples using immunohistochemistry. We performed suppression analysis of PRMT1 using small interfering RNA to determine the biological roles of PRMT1 in chemosensitivity. RESULTS: PRMT1 and FOXO1 in GC samples were predominantly expressed in the nucleus. Patients with lower PRMT1 expression (n = 131) had suppressed nuclear accumulation of FOXO1, higher recurrence after adjuvant chemotherapy, and poorer prognosis than those with higher PRMT1 expression (n = 64). PRMT1 downregulation in GC cells by RNA interference inhibited cisplatin and 5-fluorouracil sensitivity. The expression of phosphorylated FOXO1 and phosphorylated BCL-2 antagonist of cell death was upregulated in PRMT1 small interfering RNA groups. CONCLUSION: Our data suggest that the evaluation of PRMT1 expression in GC is a useful predictor of poor prognosis and recurrence after adjuvant chemotherapy. Moreover, these data suggest that PRMT1 is a promising therapeutic tool for overcoming refractory GC.

Elemental and immunohistochemical analysis of the lungs and hilar lymph node in a patient with asbestos exposure, a pilot study.

OBJECTIVES: Studies have shown that inhaled mine dust, such as asbestos, can be translocated to various organs including the lymph nodes. Recently, we have established a protocol that enables us to identify inhaled elements using paraffin embedded lung specimens by in-air microparticle-induced X-ray emission (micro-PIXE). However, little research has examined the concentration of these inhaled fibers in various organs or the mechanisms of their translocation. In this study, we compared the concentration of inhaled fibers in the lung parenchyma to the concentration in the hilar lymph node as well as to determine the elemental spatial distribution of the inhaled fibers in a patient with occupational asbestos exposure. METHODS: Lung tissues and hilar lymph node in a patient with asbestos exposure were used in this study. Elemental analysis was performed by in-air micro-PIXE. Immunohistochemical analysis was performed using anti CD163, smooth muscle actin, vimentin and ß-catenin antibody. RESULTS: The analysis revealed that the amount of inhaled silicon was approximately 6 times higher in the lymph node than in the lungs. The spatial analysis showed that silicon, iron and aluminium were co-localized in the hilar lymph node. The immunohistochemical analysis showed localized agreement of the inhaled fibers with macrophages, smooth muscle actin, and vimentin in the hilar lymph node. CONCLUSIONS: This study showed that in-air micro-PIXE could be useful for analyzing the elemental distribution and quantification of inhaled fibers in the human body. Furthermore, immunohistochemistry in combination with in-air micro-PIXE analyses may help to determine the mechanism of mine dust distribution in vivo.

MicroRNA-7 expression in colorectal cancer is associated with poor prognosis and regulates cetuximab sensitivity via EGFR regulation.

MicroRNA-7 (miR-7) has been reported to be a tumor suppressor in all malignancies including colorectal cancer (CRC). However, its significance for CRC clinical outcomes has not yet been explored. The potential for miR-7 to act as a tumor suppressor by coordinately regulating the epidermal growth factor receptor (EGFR) signaling pathway at several levels was examined. We investigated the tumor inhibitory effect of miR-7 in CRC, with particular focus on the relationship between miR-7 and the EGFR pathway. Quantitative reverse transcription-PCR was used to evaluate miR-7 expression in 105 CRC cases to determine the clinicopathologic significance of this miRNA. The regulation of EGFR by miR-7 was examined with miR-7 precursor-transfected cells. Furthermore, we investigated whether miR-7 suppresses proliferation of CRC cells in combination with cetuximab, a monoclonal antibody against EGFR. Multivariate analysis indicated that low miR-7 expression was an independent prognostic factor for poor survival (P = 0.0430). In vitro assays showed that EGFR and RAF-1 are direct targets of miR-7, which potently suppressed the proliferation of CRC cells, and, interestingly, that the growth inhibitory effect of each of these was enhanced by cetuximab. miR-7 is a meaningful prognostic marker. Furthermore, these data indicate that miR-7 precursor, alone or in combination with cetuximab, may be useful in therapy against CRC.

Nuclear PROX1 is Associated with Hypoxia-Inducible Factor 1α Expression and Cancer Progression in Esophageal Squamous Cell Carcinoma.

BACKGROUND: Transcription factor prospero homeobox 1 (PROX1) has been identified as a master regulator of lymphangiogenesis associated with metastasis. Although PROX1 expression has been investigated in several cancers, its clinical significance remains controversial and needs further validation. In this study, we investigated the clinical and functional significance of PROX1 and PROX1 regulator hypoxia-inducible factor 1α (HIF1α) in esophageal squamous cell carcinoma (ESCC). METHODS: A total of 117 samples from ESCC patients were analyzed for PROX1, HIF1α, and E-cadherin expression by immunohistochemistry; correlation with clinicopathological characteristics was determined. PROX1 function was evaluated in PROX1 small interfering RNA (siRNA)-transfected human ESCC cells in vitro by assessing cell proliferation and migration. RESULTS: PROX1 expression was higher in ESCC than in normal tissues. Patients with higher PROX1 expression (n = 26) had increased nuclear accumulation of HIF1α (p = 0.004) and more advanced metastasis, both lymph node (N factor; p = 0.09) and hematogenous (M factor; p = 0.04), than those with lower PROX1 expression (n = 91). In addition, high PROX1 and HIF1α expression correlated with low levels of E-cadherin, an epithelial cell marker. Analysis of overall and cancer-specific survival indicated that elevated PROX1 expression was significantly correlated with poor prognosis (p = 0.0064). PROX1 downregulation in ESCC cells inhibited cellular proliferation and migration (p < 0.05). Hypoxia restored PROX1 levels that were reduced by PROX1-specific siRNA. CONCLUSION: Our data suggest that high expression of PROX1 in ESCC could be used as an indicator of poor prognosis, and that PROX1 is a promising candidate molecular target for ESCC treatment.

SIRT6 expression is associated with poor prognosis and chemosensitivity in patients with non-small cell lung cancer.

BACKGROUND: Despite advances in the development of various therapeutic agents, non-small cell lung cancer (NSCLC) is associated with a poor prognosis. To improve the prognosis of patients with NSCLC, new therapeutic targets for overcoming drug resistance are required. The process of autophagy is required to support the tumorigenesis and drug resistance of cancer cells. We investigated the clinical significance of SIRT6, a member of the NAD(+) -dependent deacetylase family, which regulates a variety of cancer-related processes, including autophagy. METHODS: Immunohistochemistry analysis of SIRT6 expression and localization in 98 NSCLC clinical specimens and in vitro analysis using SIRT6-knockout lung carcinoma cell lines were performed. RESULTS: Patients with high cytoplasmic expression and low nuclear expression of SIRT6 (n = 33) had more aggressive cancer, shorter overall survival, and shorter recurrence-free survival than did patients with different SIRT6 expression profiles (P < 0.05). In vitro analysis revealed that SIRT6 knockdown lung adenocarcinoma cell line improved paclitaxel sensitivity (P < 0.05) and reduced the expression levels of both nuclear factor kappaB and autophagy marker Beclin1. CONCLUSION: Our data demonstrated that SIRT6 expression in NSCLC could be a useful prognostic marker and that SIRT6 might represent a novel target gene for predicting sensitivity of chemotherapy in lung adenocarcinoma.

Stathmin1 regulates p27 expression, proliferation and drug resistance, resulting in poor clinical prognosis in cholangiocarcinoma.

Patients with extrahepatic cholangiocarcinoma (EHCC) have a poor prognosis; postoperative survival depends on cancer progression and therapeutic resistance. The mechanism of EHCC progression needs to be clarified to identify ways to improve disease prognosis. Stathmin1 (STMN1) is a major cytosolic phosphoprotein that regulates microtubule dynamics and is associated with malignant phenotypes and chemoresistance in various cancers. Recently, STMN1 was reported to interact with p27, an inhibitor of cyclin-dependent kinase complexes. Eighty EHCC cases were studied using immunohistochemistry and clinical pathology to determine the correlation between STMN1 and p27 expression; RNA interference to analyze the function of STMN1 in an EHCC cell line was also used. Cytoplasmic STMN1 expression correlated with venous invasion (P = 0.0021) and nuclear p27 underexpression (P = 0.0011). Patients in the high-STMN1-expression group were associated with shorter recurrence-free survival and overall survival than those in the low-expression group. An in vitro protein-binding assay revealed that cytoplasmic STMN1 bound to p27 in the cytoplasm, but not in the nucleus of EHCC cells. Moreover, p27 accumulated in EHCC cells after STMN1 suppression. STMN1 knockdown inhibited proliferation and increased the sensitivity of EHCC cells to paclitaxel. STMN1 contributes to a poor prognosis and cancer progression in EHCC patients. Understanding the regulation of p27 by STMN1 could provide new insights for overcoming therapeutic resistance in EHCC.

Nuclear karyopherin-α2 expression in primary lesions and metastatic lymph nodes was associated with poor prognosis and progression in gastric cancer.

Karyopherin-α2 (KPNA2) functions as an adaptor that transports several proteins to the nucleus. We investigated the clinical and functional significance of KPNA2 in gastric cancer (GC). Immunohistochemistry was performed to examine KPNA2 expression in primary GC and metastatic lymph nodes. Next, KPNA2 was suppressed by small interfering RNA (siRNA) to examine KPNA2 function in proliferation and cisplatin-induced apoptosis of GC cell lines. Nuclear expression of KPNA2 in marginal regions of primary GC was stronger than in central regions of GC and normal tissues. The high expression of marginal KPNA2 was significantly associated with ß-catenin accumulation in the nucleus and poor prognosis in two independent GC cohorts (discovery cohort, n = 90, P = 0.018; validation cohort, n = 89, P = 0.0125). We detected correlations between nuclear KPNA2 expression in marginal region and progression of macroscopic type (P = 0.036), tumor depth (P = 0.013), lymph node metastasis (P = 0.0064), venous invasion (P = 0.034) and clinical stage (P = 0.0006). Nuclear KPNA2 expression in marginal regions of metastatic lymph nodes was significantly higher than in the central region. It was associated with poor survival of GC patients with lymph node metastasis (n = 96; center, P = 0.4384; marginal, P < 0.0001). KPNA2 suppression enhanced cisplatin-induced apoptosis and reduced proliferation in the KPNA2 siRNA group compared with the control siRNA group. The expression of the DNA repair gene NBS1 (NBN) in the nucleus was suppressed in KPNA2-suppressed cells. KPNA2 might be a useful prognostic marker and an effective therapeutic target for GC.

Forkhead box protein C2 contributes to invasion and metastasis of extrahepatic cholangiocarcinoma, resulting in a poor prognosis.

Extrahepatic cholangiocarcinoma (EHCC) is a cancer with a poor prognosis, and the postoperative survival of patients depends on the existence of invasion and metastasis. The epithelial-to-mesenchymal transition (EMT) is an important step in EHCC invasion and metastasis. Forkhead box protein C2 (FOXC2) is a transcription factor that has been reported to induce the EMT. Therefore we examined the correlation between FOXC2 expression and clinical pathological factors, and analysed the function of FOXC2. The expression of FOXC2 in 77 EHCC cases was investigated by immunohistochemical staining, and the relationship between FOXC2 expression and clinicopathological factor was assessed. Knockdown by small interfering RNA (siRNA) was performed to determine the roles of FOXC2 in EHCC cell line. FOXC2 expression correlated with lymph node metastasis (P = 0.0205). Patients in the high FOXC2 expression group had a poorer prognosis than the patients in the low FOXC2 expression group. Moreover, FOXC2 knockdown inhibited cell motility and invasion, and decreased the expression of EMT markers (N-cadherin, and matrix metalloproteinase (MMP) -2) and Angiopietin-2 (Ang-2). The EMT inducer FOXC2 contributes to a poor prognosis and cancer progression. FOXC2 may be a promising molecular target for regulating EHCC metastasis.

Carbonic anhydrase 9 expression is associated with poor prognosis, tumor proliferation, and radiosensitivity of thymic carcinomas.

INTRODUCTION: Thymic epithelial tumors (TETs) comprise several histologies of thymoma and thymic carcinomas (TCs), and TC frequently metastasizes and causes death. We therefore aimed here to identify key molecules closely related to prognosis and their biological roles in high-risk TETs, particularly TCs. RESULTS: RNA sequence analysis demonstrated that hypoxia-related genes were highly expressed in TETs. The expression of the hypoxia-related gene CA9 was noteworthy, particularly in TCs. Immunohistochemical analysis revealed that CA9 was expressed in 81.0% of TCs and 20.7% of all TET samples. CA9 expression was significantly associated with Masaoka stage, WHO classification, and recurrence-free survival after tumor resection (P = 0.005). The down-regulation of CA9 transcription in TC cell lines by small interfering RNAs significantly inhibited CA9 expression, which inhibited proliferation and increased sensitivity to irradiation. CONCLUSIONS: CA9 expression may serve as a significant prognostic marker of TETs and therefore represents a potential target for the development of novel drugs and radiation-sensitizing therapy designed to improve the outcomes of patients with TCs. MATERIALS AND METHODS: We performed comprehensive transcriptome sequencing of 23 TETs and physiologic thymic specimens to identify genes highly and specifically expressed in high-risk TETs, particulary TCs. We performed immunohistochemical analysis of 179 consecutive surgically resected TETs to evaluate the significance of the association of protein expression with clinicopathological features and prognosis. The biological significance of the most promising prognostic marker was further studied using the TC cell lines, Ty-82 and MP57.

Relationship between LAT1 expression and resistance to chemotherapy in pancreatic ductal adenocarcinoma.

PURPOSE: L-type amino acid transporter 1 (LAT1) is linked to tumor cell proliferation, angiogenesis, and survival in various human cancers. Although the expression of LAT1 was identified as a significant prognostic predictor after surgery in patients with pancreatic ductal adenocarcinoma (PDAC), little is known about the clinical significance of LAT1 as a chemotherapeutic resistance factor in PDAC. METHODS: A total of 110 patients with surgically resected PDAC were retrospectively reviewed as the training set. Immunohistochemical staining of resected tumor specimens was assessed using anti-LAT1 antibodies. In vitro analysis of chemotherapy resistance and LAT1 function using PDAC cell lines was also performed. RESULTS: The rate of high expression of LAT1 was 64.1% (71/110). The high expression of LAT1 protein was significantly associated with tumor differentiation, tumor depth (T factor), lymph node metastasis, venous invasion, recurrence, and clinical response. By multivariate analysis, LAT1 was validated as an independent prognostic factor for predicting worse survival after surgery. We analyzed the TCGA data set and obtained similar results that the survival rates of SLC7A5 high expression group were poorer than that of low expression group. LAT1 could successfully predict the outcome of patients who received adjuvant chemotherapy after surgery (n = 88) and systemic chemotherapy after recurrence (n = 56). All patients with high LAT1 expression were non-responders, whereas approximately 30% of the patients with low LAT1 expression responders (p = 0.0002). By analyzing the TCGA online database, it was found that LAT1 closely correlated with hypoxia-induced genes, such as PTGES, PYGL, and KPNA2. CONCLUSION: LAT1 as an independent prognostic marker is a potential molecular targeting gene to reduce chemoresistance and tumor growth in patients with PDAC, supported by our in vitro study.

High expression of carcinoembryonic antigen and telomerase reverse transcriptase in circulating tumor cells is associated with poor clinical response to the immune checkpoint inhibitor nivolumab.

The present study aimed to enrich circulating tumor cells (CTCs) from blood samples using a new size-sorting CTC chip. The present study also set out to identify a blood sensitivity marker for the immune checkpoint inhibitor nivolumab in patients with advanced, pre-treatment lung cancer. The CTC sorting efficacy of the chip was investigated and the large cell fraction of blood samples from 15 patients with pre-treatment lung cancer who were later administered nivolumab were purified. The expression levels of carcinoembryonic antigen (CEA), human Telomerase Reverse Transcriptase (hTERT), cytokeratin19 (CK19), and programmed death ligand-1 (PD-L1) were investigated to clarify the association between these CTC markers and the clinical response to nivolumab. The CTC chip effectively enriched cells from lung cancer cell line PC-9. The large cell fraction had a high expression of CEA and hTERT, with the former being significantly associated with the clinical response to nivolumab. The expression of CEA and hTERT in CTCs derived from the blood of a patient with lung cancer were also validated. The evaluation of CEA and possibly hTERT in CTCs collected by the CTC chip may represent a promising predictive blood marker for sensitivity to nivolumab. To the best of our knowledge this is the first report to describe the predictive CTC marker for nivolumab in pre-treatment patients.