The Expression of Melanoma-Associated Antigen D2 Both in Surgically Resected and Serum Samples Serves as Clinically Relevant Biomarker of Gastric Cancer Progression.

BACKGROUND: Sensitive biomarkers are necessary for risk classification of patients with gastric cancer (GC), especially ones at risk of distant metastases. Melanoma-associated antigen (MAGE)-D2 has been reported to play a role in the process of cell adhesion and metastatic potential of tumor cells in colorectal cancer. The purpose of this study was to identify a novel clinically relevant biomarker of GC. METHODS: Expression analysis of MAGE-D2 was conducted in GC cell lines and clinical samples (surgical specimen and serum) in both mRNA and protein level. Correlations between MAGE-D2 expression status and clinicopathological factors were evaluated. RESULTS: MAGE-D2 mRNA expression levels were similar between GC tissues and the corresponding normal adjacent tissues and were independent of GC differentiation or subtype. In 101 (45 %) of 225 patients, the expression level of MAGE-D2 mRNA was increased in GC tissues compared with the corresponding normal adjacent tissues. Increased expression of MAGE-D2 mRNA in GC tissues was associated with distant metastasis and early recurrence and was an independent prognostic factor (hazard ratio 2.27, 95 % confidence interval 1.39-3.74, P = 0.001). There was a stepwise increase in serum MAGE-D2 level going from healthy volunteers to patients with localized GC and then to those with extended GC (stage IV). Patients with preoperative serum MAGE-D2 levels >130 pg/ml had a more unfavorable prognosis than those with levels ≤130 pg/ml. CONCLUSION: MAGE-D2 was associated with metastatic potential of GC and may represent a promising biomarker, both in gastric tissues and serum samples, for malignant behavior of GC.

[Suggesting the Significance of Pericardial Fat Pad in Bronchial Stump Fistula].

Bronchial stump fistula is a post-operative complication with poor outcome after pulmonary lobectomy. In order to prevent this complication, the bronchial stump is covered with pericardial fat tissue in our hospital. The case was 58 year old male who received adjuvant chemotherapy after sigmoidectomy for sigmoid colon cancer. As he developed multiple pulmonary metastases, 48 courses of chemotherapy were performed. The lesions had been localized at the right lower lobe, and neither increase in the size of these lesions nor development of other lesions were observed. Hence, an operation was performed. After right lower lobectomy, the bronchial stump was covered with the pericardial fat tissue. Three months after the operation, he developed pneumothorax, and bubbles were detected inside the fat. The pneumothorax was cured conservatively, and the bubbles disappeared spontaneously after 10 months. It is rare that the patient with bubbles in the covering tissue observed for a long time is cured conservatively, suggesting the significance of the stump pad.

Reduced Expression of Adherens Junctions Associated Protein 1 Predicts Recurrence of Hepatocellular Carcinoma After Curative Hepatectomy.

BACKGROUND: Hepatocellular carcinoma (HCC) frequently recurs after curative resection. Therefore, the availability of sensitive biomarkers for progression and recurrence is essential for managing patients' clinical course. Adherens junctions associated protein 1 (AJAP1) may serve this purpose, because it mediates activities of tumor cells. METHODS: AJAP1 mRNA levels and those of genes encoding potential interacting proteins, such as SRC in HCC cell lines, and 144 pairs of resected liver tissues were determined as well as the methylation status of the AJAP1 promoter and copy number changes at AJAP1 locus. The expression pattern of AJAP1 protein was evaluated using immunohistochemistry. RESULTS: AJAP1 mRNA levels varied among nine HCC cell lines, and AJAP1 expression was reactivated after demethylation of its promoter. AJAP1 mRNA levels correlated inversely with those of SRC in HCC cell lines and tissues. AJAP1 mRNA levels were suppressed in HCC tissues. The expression pattern of AJAP1 correlated significantly with that of AJAP1 mRNA. Low levels of AJAP1 mRNA in patients with HCC associated significantly with elevated levels of tumor markers, larger tumor size, serosal infiltration, vascular invasion, hypermethylation of the AJAP1 promoter, and copy number loss at AJAP1 locus. Patients with low levels of AJAP1 expression were more likely to experience shorter disease-free survival (DFS), and multivariate analysis identified low AJAP1 expression as an independent factor for predicting DFS. CONCLUSIONS: AJAP1 may function as a key regulatory molecule associated with the recurrence of HCC. Hypermethylation of the AJAP1 promoter is a key regulatory mechanism controlling AJAP1 expression.

Suppression of SAMSN1 Expression is Associated with the Malignant Phenotype of Hepatocellular Carcinoma.

BACKGROUND: Identification of molecular markers for sensitive detection of hepatocellular carcinoma (HCC) is required to achieve efficacious personalized therapy. METHODS: We focused here on SAM domain, SH3 domain, and nuclear localization signals 1 (SAMSN1) and investigated expression and methylation status of SAMSN1 in HCC cell lines and 144 pairs of surgical specimens. RESULTS: SAMSN1 was expressed at significantly lower levels in tumor tissue compared with the corresponding noncancerous tissues of patients with HCC. Analysis of HCC cell lines revealed that hypermethylation of the SAMSN1 promoter correlated with decreased expression of SAMSN1 mRNA. Furthermore, treating cells with a DNA-demethylating drug increased SAMSN1 transcription. The levels of SAMSN1 mRNA in noncancerous liver were not affected by background liver inflammation or fibrosis. Moreover, the levels of SAMSN1 mRNA in HCC tissues inversely correlated with tumor size and preoperative levels of proteins induced by vitamin K absence. The clinical significance of SAMSN1 was further indicated by the correlation between its decreased expression in patients with HCC and their shorter overall and recurrence-free survival as well as recurrence following initial resection. Moreover, multivariate analysis identified SAMSN1 as an independent prognostic factor of HCC progression. The expression pattern of SAMSN1 correlated significantly with that of SAMSN1 mRNA, making it possible to use PCR techniques to readily quantitate SAMSN1 expression in tumors. CONCLUSIONS: Our findings indicate that inhibition of SAMSN1 transcription through DNA hypermethylation may influence the progression of HCC and thus represent a novel biomarker of the phenotype of HCC cells.

Prognostic impact of expression and methylation status of DENN/MADD domain-containing protein 2D in gastric cancer.

BACKGROUND: Patients with advanced gastric cancer (GC) have an adverse prognosis even after curative resection. Development of novel diagnostic and therapeutic approaches for GC is urgently required. METHODS: The expression and methylation status of DENN/MADD domain-containing protein 2D (DENND2D), a member of the membrane trafficking proteins, were evaluated in 12 GC cell lines and 112 pairs of surgical specimens. Subgroup analysis based on tumor differentiation, location, and morphology was also performed. Expression and distribution of DENND2D protein were determined by immunohistochemistry. RESULTS: The majority of GC cell lines (75%) and tissues (79%) showed reduced expression of DENND2D mRNA compared with noncancerous gastric tissues. GC tissues showed a significantly lower mean expression level of mRNA and a higher frequency of promoter hypermethylation of DENND2D than corresponding noncancerous tissues. No significant differences in DENND2D mRNA expression and methylation status were found between GC subtypes categorized by tumor differentiation, location, and morphology. The expression patterns of DENND2D protein were confirmed to be consistent with those of DENND2D mRNA. Downregulation of DENND2D mRNA in GC tissues was significantly associated with factors related to more advanced GC and subsequent adverse prognosis. Among 72 patients who underwent R0 resection, downregulation of DENND2D mRNA in GC tissues was an independent prognostic factor and associated with early recurrence. CONCLUSIONS: Our results suggested that DENND2D is a putative tumor suppressor gene regulated by promoter hypermethylation in GC. Downregulation of DENND2D can serve as a novel tumor biomarker to predict progression and early recurrence of all types of GC.

Diversity of clinical implication of B-cell translocation gene 1 expression by histopathologic and anatomic subtypes of gastric cancer.

BACKGROUND: Genetic signatures may differ by histopathologic and anatomic subtypes of gastric cancer (GC). B-cell translocation gene 1 (BTG1) was identified as one of genes downregulated in GC tissues from our microarray data. AIMS: To evaluate the clinical implications of BTG1 expression in GC and the genetic diversity among GC subtypes. METHODS: BTG1 mRNA expression was analyzed in GC cell lines and 233 pairs of surgical specimens. The mutational and methylation status of BTG1 in GC cell lines was analyzed, and immunohistochemistry was conducted to determine the distribution of BTG1. The pattern and prognostic significance of BTG1 expression were correlated with the three proposed GC subtypes. RESULTS: BTG1 mRNA was downregulated in 82 % of GC cell lines and in 88 % of clinical GC tissues. Promoter hypermethylation events or sequence mutations were not detected in GC cell lines. The pattern of BTG1 expression as observed by immunohistochemistry was consistent with that of its mRNA. Downregulation of BTG1 mRNA in GCs was significantly associated with shorter disease-specific and recurrence-free survival. Multivariate analysis of disease-specific survival identified downregulation of BTG1 transcription as an independent prognostic factor. BTG1 mRNA expression was more strongly suppressed in proximal nondiffuse and diffuse GC compared with distal nondiffuse GC, and subgroup analysis revealed that BTG1 downregulation led to adverse prognosis, specifically in patients with proximal nondiffuse and diffuse GC. CONCLUSIONS: Altered expression of BTG1 is a potential biomarker for carcinogenesis and progression of GC, particularly for proximal nondiffuse and diffuse GC.

Method of bilateral pleural drainage by single Blake drain after esophagectomy.

BACKGROUND: Clinicians often encounter left pleural effusion after esophagectomy, which sometimes necessitates thoracentesis. We have introduced a new drainage method, bilateral pleural drainage by single Blake drain (BDSD), which we have been using since April 2013. This study aims to evaluate the performance of the BDSD. METHODS: The BDSD method employs a 15-F Blake drain inserted from the right thoracic cavity to the left thoracic cavity across the posterior mediastinum. The conventional drain (CD) group consisted of 50 patients with a 19-F Blake drain placed in the right thoracic cavity during the period from April 2012 to March 2013. The BDSD group consisted of 54 patients treated from April 2013 to June 2014. RESULTS: The amount of total drainage in the BDSD group was significantly higher than that in the CD group (P < 0.0001). The rates of left pleural effusion and left lower lobe atelectasis in the BDSD group were significantly lower than those in the CD group (P < 0.0001 and P < 0.0001, respectively). No patients developed a left pleural effusion necessitating thoracentesis drainage in the BDSD group. CONCLUSIONS: Compared with the conventional method, BDSD was able to evacuate bilateral pleural effusion more effectively, and the incidences of left pleural effusion and left atelectasis were lower. This method is therefore clinically useful after esophagectomy.

Feeding duodenostomy decreases the incidence of mechanical obstruction after radical esophageal cancer surgery.

BACKGROUND: Nutritional support influences the outcome of gastroenterological surgery, and enteral nutrition effectively mitigates postoperative complications in highly invasive surgery such as resection of esophageal cancer. However, feeding via jejunostomy can cause complications including mechanical obstruction, which could be life threatening. From 2009, we began enteral feeding via duodenostomy to reduce the likelihood of complications. In this study, we compared duodenostomy with the conventional jejunostomy feeding, mainly looking at the catheter-related complications. METHODS: The database records of 378 patients with esophageal cancer who underwent radical esophagectomy with retrosternal or posterior mediastinal gastric tube reconstruction in our department from January 1998 to December 2012 were examined. Of the 378 patients, 111 underwent feeding via duodenostomy (FD) and 267 underwent feeding via jejunostomy (FJ), and their records were reviewed for the following catheter-related complications: site infection, dislodgement, peritonitis, and mechanical obstruction. RESULTS: Mechanical obstruction occurred in 12 patients in the FJ group but none in the FD group (4.5 % vs. 0 %, P = 0.023). Of the 12 cases, 7 (58.3 %) required surgery of which 2 had bowel resection due to strangulated mechanical obstruction. Catheter site infection was seen in 14 cases in the FJ group, of which 2 (14.2 %) had peritonitis following catheter dislocation, while only one case of site infection was seen in the FD group (5.2 % vs. 0.9 %, P = 0.078). CONCLUSIONS: Feeding via duodenectomy could be the procedure of choice since neither mechanical obstruction nor relaparotomy was seen during enteral feeding through this technique.

Clinical significance of expression and epigenetic profiling of TUSC1 in gastric cancer.

BACKGROUND AND OBJECTIVES: The prognosis of advanced gastric cancer (GC) remains dismal. The aim of this study was to identify a novel tumor suppressor gene (TSG) with repressed transcription by aberrant DNA methylation in GC. METHODS: The expression and methylation status of tumor suppressor candidate 1 (TUSC1) were evaluated in GC cell lines and 112 pairs of surgical specimens. TUSC1 protein expression and distribution in GC tissue were determined by immunohistochemistry. RESULTS: The majority of GC cell lines (83%) and GC tissues (82%) showed downregulation of TUSC1 mRNA compared with noncancerous tissues. No significant differences were found in TUSC1 mRNA expression between three GC subtypes categorized by tumor locations and morphology. Reduced expression of TUSC1 mRNA in GC tissues was significantly associated with advanced T stage, vessel invasion and lymph node metastasis, leading to poor prognosis. The expression patterns of TUSC1 protein were confirmed to be consistent with those of TUSC1 mRNA. Sixty-three (57%) of 112 patients showed intragenic hypermethylation of TUSC1 in GC tissues. CONCLUSIONS: Our results suggested that reduced expression of TUSC1 mRNA was related to poor prognosis and TUSC1 is a putative TSG that is suppressed through intragenic hypermethylation in GC.

Evaluation of MAGE-D4 expression in hepatocellular carcinoma in Japanese patients.

BACKGROUND AND OBJECTIVES: Though Melanoma-associated antigen (MAGE) family genes have received lots of attention as cancer-related genes and targets for immunotherapy, MAGE-D4 expression in hepatocellular carcinoma (HCC) has not yet been evaluated. METHODS: MAGE-D4 mRNA expression was assayed in nine HCC cell lines and 94 HCC surgical specimens obtained from Japanese patients by quantitative real-time reverse transcription polymerase chain reaction, and the correlations between MAGE-D4 mRNA expression and clinicopathological factors were evaluated. The expression and distribution of MAGE-D4b protein were evaluated immunohistochemically. RESULTS: MAGE-D4 mRNA was overexpressed in five of nine HCC cell lines and 34 of 94 primary HCCs (36.2%). Median overall survival (14.8 vs. 118 months, P < 0.001) and relapse-free survival (2.7 vs. 18.3 months, P < 0.001) were significantly shorter in patients with high than with low-moderate MAGE-D4 expression. Multivariate analysis for overall survival showed that MAGE-D4 overexpression was independently prognostic for survival (hazard ratio 2.88, P = 0.009) and significantly associated with high alpha-fetoprotein concentration (P < 0.001), poor tumor differentiation (P = 0.003) and vascular invasion (P = 0.021). MAGE-D4b protein expression patterns were consistent with those of MAGE-D4 mRNA. CONCLUSIONS: Overexpression of MAGE-D4 may be a predictive marker of early recurrence and mortality in patients with HCC.

Mandatory palliative care education for surgical residents: initial focus on teaching pain management.

BACKGROUND: Knowledge concerning palliative care and the associated skills, including effective pain control, is essential for surgeons who treat cancer patients in daily practice. This study focuses on a palliative care training course that has been mandatorily conducted for all surgical residents of our hospital since 2009. METHODS: We evaluated the effectiveness of our mandatory palliative care training course by conducting a retrospective study of the patients' medical records and participants' questionnaire results and discussed the importance of palliative care education for surgical residents. RESULTS: All 12 surgical residents who participated in the course in 2009 had graduated 4-9 years back. They were assigned to look after a total of 92 cases (average, 7.66 cases per resident) during the course. The purpose of care in most cases (92.3%) was to mitigate pain. Introducing analgesic adjuvants such as gabapentin or amitriptyline accounted for the largest part of initial interventions (23.9%) aimed at controlling cancer pain, followed by changes in route of administration or doses of prior opioid analgesics (21.7%). Interventions with opioid analgesics were conducted most frequently (47.7%). The overall pain improvement rate was 89.1%. We used a questionnaire after the course to evaluate its effectiveness. CONCLUSIONS: The surgical residents stated that it was a meaningful course through which they gained practical knowledge on palliative care and that the experience would change their approach to home care.

Curative surgery for gastric cancer of the elderly in a Japanese regional hospital.

BACKGROUND/AIMS: The aim of this study was to identify the factors influencing mortality, morbidity and survival for gastric cancer in patients 80 years of age and older. METHODOLOGY: This retrospective study of gastric cancer in the elderly was conducted from 2003 to 2008. We examined demographic data, treatment, causes of death and their overall survival. RESULTS: On gastric cancer in the elderly, the stage IV was significantly higher in non-surgery group (47%) than in surgery group (12%). Moreover, non-surgery group had significantly more cardiac disease (p = 0.007) and previous stroke (p = 0.035) than surgery group. Differences in overall survival were statistically significant among stage I (p = 0.025) and stage II/III (p <0.001) patients. The other, the overall survival difference was not statistically significant between surgery group and non-surgery group, in stage IV (p = 0.05). CONCLUSIONS: In the study, age is not the only contraindication to resection for gastric cancer because when elderly patients undergo curative resection, they do not have a worse prognosis than without surgery group. In the elderly, the surgical strategy must be always modulated on the basis of preoperative comorbidities, the degree of the tumor spread, and the expected equality of life offered by a surgical procedure.

A case of lymph node metastasis following a curative endoscopic submucosal dissection of an early gastric cancer.

Currently in Japan, differentiated gastric submucosal invasive cancers <500 µm (SM1) with negative lymphovascular involvement are included in expanded pathological criteria for curative endoscopic treatment. This is based on a retrospective examination of surgical resection cases in which patients suitable for such expanded criteria were determined to have a negligible risk of lymph node metastasis. We performed endoscopic submucosal dissection on a 65-year-old male with early gastric cancer in April 2005, and pathology revealed a well-differentiated adenocarcinoma, 21 × 10 mm in size, SM1 invasion depth and negative lymphovascular invasion as well as tumor-free margins, so the case was diagnosed as a curative resection. This case, however, resulted in lymph node metastasis that was diagnosed by endoscopic ultrasonography with fine-needle aspiration biopsy in May 2009. Distal gastrectomy with D2 lymph node dissection was then performed, confirming lymph node metastasis from the original gastric cancer.

[A case of advanced gastric cancer that a medical therapy effect was provided grade 3 by a histopathological diagnosis after long-term chemotherapy].

A 64-year-old man underwent long-term chemotherapy for advanced gastric cancer with para-aortic lymph node metastasis (cT3 N3 M0 P0, cStage IV). S-1 (120 mg/day) was orally administered for 14 days and CDDP (60 mg/m2) was administered 10 times by intravenous drip on day 8. Next, paclitaxel (PTX 80 mg/m2) was administered 12 times by intravenous drip on days 1, 8 and 15. After 10 S-1/CDDP courses and 12 paclitaxel courses, the lymph node swelling decreased in size, but the tumor increased. CPT-11 (100 mg/m2) was administered as third-line therapy by intravenous drip on days 1, 8, 15 and 22. A partial response (PR) was obtained after 2 courses, but due to severe pyloric stenosis, a food passage disorder appeared. We performed distal gastrectomy with D2 lymph node dissection. The histological diagnosis revealed a complete disappearance of cancer cells in the stomach and lymph nodes.

Prognostic relevance of SAMSN1 expression in gastric cancer.

The prognosis for patients with advanced gastric cancer (GC) remains poor. The identification of biomarkers relevant to the recurrence and metastasis of GC is advantageous for stratifying patients and proposing novel molecular targets. In the present study the oncological roles of SAM domain, SH3 domain and nuclear localization signals 1 (SAMSN1), a mediator of B-cell function, were elucidated in GC. The expression and methylation status of SAMSN1 were investigated in a panel of 11 GC cell lines. Immunohistochemical staining was performed to determine the pattern of SAMSN1 protein expression in gastric tissues. The prognostic impact of SAMSN1 expression was determined by analyzing 175 pairs of surgically resected gastric tissues. A marked decrease in the level of SAMSN1 mRNA was detected in 8/11 GC cell lines as compared with that in a non-transformed intestinal epithelium cell line (FHs 74) without promoter methylation. The mean expression level of SAMSN1 mRNA was reduced in GC tissues compared with normal adjacent tissues, an observation that was independent of tumor differentiation. The pattern of SAMSN1 protein expression was significantly correlated with that of SAMSN1 mRNA. Low SAMSN1 mRNA expression was significantly associated with tumor size (>60 mm; P=0.026) and shorter overall survival times (P=0.004). Multivariate analysis identified low SAMSN1 mRNA expression as an independent prognostic factor for poor overall survival (hazard ratio, 1.80; 95% confidence interval, 1.07-3.05; P=0.025). The difference in survival between the low and high SAMSN1 expression groups was more marked in patients with stage II/III GC compared to those with stage IV GC. In patients with stage II/III GC who underwent curative surgery, low SAMSN1 expression was associated with reduced disease free survival times. The results of the present study indicate that downregulation of SAMSN1 transcription may affect the progression and recurrence of GC, and therefore may represent a novel biomarker of GC.

Dihydropyrimidinase-like 3 is a putative hepatocellular carcinoma tumor suppressor.

BACKGROUND: Patients with hepatocellular carcinoma (HCC) may relapse after curative resection. Sensitive biomarkers for HCC are required to enhance disease management. Dihydropyrimidinase-like 3 (DPYSL3) suppresses cell proliferation and tumorigenicity of certain malignancies; however, its role in HCC is unknown. METHODS: The expression levels of DPYSL3 and genes encoding potential interacting proteins vascular endothelial growth factor (VEGF), focal adhesion kinase (FAK), ezrin, and cellular src were determined using RT-PCR. Further, we determined the methylation status of the DPYSL3 promoter in HCC cells lines and the effect of inhibiting DPYSL3 expression on their phenotype. DPYSL3 expression was determined in 151 pairs of resected liver tissues. RESULTS: DPYSL3 mRNA levels were down-regulated in most HCC cell lines with DPYSL3 promoter hypermethylation, and expression was restored after demethylation. DPYSL3 expression levels inversely correlated with those of VEGF and FAK. Knockdown of DPYSL3 significantly increased migration and the invasive properties of HCC cells. The mean level of DPYSL3 mRNA was significantly lower in HCC tissues compared with corresponding noncancerous tissues. The expression patterns of DPYSL3 mRNA and protein were consistent. DPYSL3 mRNA expression in HCC tissues inversely correlated with preoperative serum tumor markers and was significantly lower in patients with extrahepatic recurrences. Disease-specific and recurrence-free survival was significantly shorter in patients with down-regulated DPYSL3 expression. CONCLUSIONS: Our results indicate that DPYSL3 is a putative HCC tumor suppressor, and promoter hypermethylation potently regulates DPYSL3 transcription. Down-regulation of DPYSL3 expression in HCC tissues may serve as a predictive biomarker for HCC after curative resection.

B­cell translocation gene 1 serves as a novel prognostic indicator of hepatocellular carcinoma.

Although the B­cell translocation gene 1 (BTG1) plays an important role in apoptosis and negatively regulates cell proliferation, BTG1 expression in hepatocellular carcinoma (HCC) has not been evaluated. In this study expression analysis of BTG1 was conducted to clarify the role of BTG1 in the initiation of HCC carcinogenesis and progression. BTG1 mRNA expression levels were determined for HCC cell lines and 151 surgical specimen pairs using quantitative real­time reverse transcription polymerase chain reaction (RT­qPCR) assay. The mutational and methylation status of HCC cell lines were analyzed via high resolution melting (HRM) analysis and direct sequencing analysis to elucidate the regulatory mechanisms of BTG1 expression. The expression and distribution of the BTG1 protein in liver tissues were evaluated using immunohistochemistry (IHC). Decreased expression of BTG1 mRNA was confirmed in the majority of HCC cell lines (89%) and clinical HCC tissues (85%) compared with non­cancerous liver tissues. Mutations or promoter hypermethylation were not identified in HCC cell lines. BTG1 mRNA expression levels were not influenced by background liver status. The pattern of BTG1 protein expression was consistent with that of BTG1 mRNA. Downregulation of BTG1 mRNA in HCC was significantly associated with shorter disease­specific and recurrence­free survival rates. Multivariate analysis of disease­specific survival rates identified BTG1 mRNA downregulation as an independent prognostic factor for HCC (hazard ratio 2.12, 95% confidence interval 1.12­4.04, P=0.022). Our results indicate that altered BTG1 expression might affect hepatocarcinogenesis and may represent a novel biomarker for HCC carcinogenesis and progression.

Aberrant expression of melanoma-associated antigen-D2 serves as a prognostic indicator of hepatocellular carcinoma outcome following curative hepatectomy.

Hepatocellular carcinoma (HCC) is the most common cause of cancer-related mortality globally. Since the prognosis of advanced HCC patients is extremely poor, the development of novel molecular targets for diagnosis and therapy is urgently required. In the present study, the expression of the melanoma-associated antigen-D2 (MAGE-D2) gene was investigated to determine whether it affects the malignant phenotype of HCC and thus, may serve as a marker of prognosis. Therefore, the expression of MAGE-D2 mRNA and MAGE-D2 protein in nine HCC cell lines and 151 pairs of surgical tissues was analyzed. mRNA expression levels were analyzed using reverse transcription-quantitative polymerase chain reaction and immunohistochemistry was used to compare the clinicopathological parameters of the tumors. A significant difference in the level of MAGE-D2 expression was observed between the normal liver and chronic hepatitis tissues, however, no significant differences were identified among the levels of the chronic hepatitis, cirrhosis and HCC tissues. The expression patterns of the MAGE-D2 protein were consistent with those of its mRNA. The expression levels of MAGE-D2 mRNA in 66 of 151 (44%) patients were higher in the HCC tissues compared with the corresponding non-cancerous tissues. In addition, the disease-specific survival time was significantly shorter for patients with higher levels of MAGE-D2 mRNA expression. Multivariate analysis identified increased expression of MAGE-D2 mRNA as an independent prognostic factor for disease-specific survival (hazard ratio, 2.65; 95% confidence interval, 1.43-4.98; P=0.002). However, increased expression levels of MAGE-D2 mRNA were not significantly associated with other clinicopathological parameters, including extrahepatic recurrence. These results indicated that MAGE-D2 mRNA affects tumor progression and may serve as a prognostic indicator following curative resection. In addition, MAGE-D2 may provide a target for the therapy of HCC.

Downregulation of DENND2D by promoter hypermethylation is associated with early recurrence of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide and its prognosis is poor. Novel targets for treating recurrence and progression along with associated biomarkers are urgently required. In this study, the expression and regulatory mechanism of DENN/MADD domain containing 2D (DENND2D) were investigated in an attempt to identify a tumor suppressor gene for HCC regulated by silencing through promoter hypermethylation. The levels of DENND2D expression in HCC cell lines and surgical specimens were determined using a quantitative polymerase chain reaction assay and the relationship between the expression levels of DENND2D mRNA and clinicopathological factors was evaluated. The expression and distribution of DENND2D were determined using immunohistochemistry. DNA methylation analysis was performed to determine the regulatory mechanisms of DENND2D expression in HCC. Most HCC cell lines (89%) and surgical specimens (78%) expressed lower levels of DENND2D mRNA compared with normal liver tissue. In contrast, there was no significant difference in the expression levels of DENND2D mRNA between normal tissues of HCC patients with and without cirrhosis. The expression patterns of DENND2D protein and mRNA were consistent. Patients with significantly lower levels of DENND2D mRNA in HCC tissues had remarkably earlier recurrences after hepatectomy and their prognosis worsened. The DENND2D promoter was methylated in eight out of nine HCC cell lines and DNA demethylation reactivated DENND2D mRNA expression. Hypermethylation of DENND2D was frequently detected in HCC tissues (75%) and was significantly associated with downregulation of DENND2D mRNA expression. DENND2D is a candidate tumor suppressor gene that is inactivated by promoter hypermethylation in patients with HCC and may serve as a novel biomarker of early recurrence of HCC.

Dihydropyrimidinase-like 3 facilitates malignant behavior of gastric cancer.

BACKGROUND: Gastric cancer (GC) remains to have a poor prognosis via diverse process of cancer progression. Dihydropyrimidinase-like 3 (DPYSL3) is a cell adhesion molecule that has been reported to be involved in the metastatic process of tumor cells. The aim of this study was to identify a novel clinically-relevant biomarker of GC. METHODS: Expression analysis of DPYSL3 mRNA and protein levels was conducted using GC cell lines and 238 pairs of surgically resected gastric tissues. Correlations between expression status of DPYSL3 and clinicopathological parameters were investigated. RESULTS: DPYSL3 mRNA expression levels positively correlated with those of potentially interacting genes (VEGF, FAK and EZR) in GC cell lines. GC tissues from tumors with distant metastases (stage IV cancer) showed elevated expression levels of DPYSL3 mRNA. The DPYSL3 staining intensity in immunochemical staining was consistent with the mRNA expression patterns in GC tissues. High DPYSL3 mRNA expression in GCs was significantly associated with more malignant phenotypes and was an independent prognostic factor. Moreover, patients with high DPYSL3 mRNA expression had a significantly shorter recurrence free survival after curative resection. In subgroup analysis based on tumor histology, similar tendency was observed between patients with differentiated and undifferentiated GCs. CONCLUSIONS: Expression status of DPYSL3 in GC tissues may represent a promising biomarker for the malignant behavior of GC.