Low blood level of tumour suppressor miR-5193 as a target of immunotherapy to PD-L1 in gastric cancer.

BACKGROUND: Recent studies have identified that low levels of some tumour suppressor microRNAs (miRNAs) in the blood contribute to tumour progression and poor outcomes in various cancers. However, no study has proved these miRNAs are associated with cancer immune mechanisms. METHODS: From a systematic review of the NCBI and miRNA databases, four tumour suppressor miRNA candidates were selected (miR-5193, miR-4443, miR-520h, miR-496) that putatively target programmed cell death ligand 1 (PD-L1). RESULTS: Test-scale and large-scale analyses revealed that plasma levels of miR-5193 were significantly lower in gastric cancer (GC) patients than in healthy volunteers (HVs). Low plasma levels of miR-5193 were associated with advanced pathological stages and were an independent prognostic factor. Overexpression of miR-5193 in GC cells suppressed PD-L1 on the surface of GC cells, even with IFN-γ stimulation. In the coculture model of GC cells and T cells stimulated by anti-CD3/anti-CD28 beads, overexpression of miR-5193 increased anti-tumour activity of T cells by suppressing PD-L1 expression. Subcutaneous injection of miR-5193 also significantly enhanced the tumour-killing activity and trafficking of T cells in mice. CONCLUSIONS: Low blood levels of miR-5193 are associated with GC progression and poor outcomes and could be a target of nucleic acid immunotherapy in GC patients.

Urinary microRNA-210-3p as a novel and non-invasive biomarker for the detection of pancreatic cancer, including intraductal papillary mucinous carcinoma.

BACKGROUND: This study aims to explore novel microRNAs in urine for screening and predicting clinical characteristics in pancreatic cancer (PC) patients using a microRNA array-based approach. METHODS: We used the Toray® 3D-Gene microRNA array-based approach to compare urinary levels between PC patients and healthy volunteers. RESULTS: (1) Four oncogenic microRNAs (miR-744-5p, miR-572, miR-210-3p, and miR-575) that were highly upregulated in the urine of PC patients compared to healthy individuals were identified by comprehensive microRNA array analysis. (2) Test-scale analysis by quantitative RT-PCR for each group of 20 cases showed that miR-210-3p was significantly upregulated in the urine of PC patients compared to healthy individuals (P = 0.009). (3) Validation analysis (58 PC patients and 35 healthy individuals) confirmed that miR-210-3p was significantly upregulated in the urine of PC patients compared to healthy individuals (P < 0.001, area under the receiver operating characteristic curve = 0.79, sensitivity: 0.828, specificity: 0.743). We differentiated PC patients into invasive ductal carcinoma (IDCa) and intraductal papillary mucinous carcinoma (IPMC) groups. In addition to urinary miR-210-3p levels being upregulated in IDCa over healthy individuals (P = 0.009), urinary miR-210-3p levels were also elevated in IPMC over healthy individuals (P = 0.0018). Urinary miR-210-3p can differentiate IPMC from healthy individuals by a cutoff of 8.02 with an AUC value of 0.762, sensitivity of 94%, and specificity of 63%. (4) To test whether urinary miR210-3p levels reflected plasma miR-210-3p levels, we examined the correlation between urinary and plasma levels. Spearman's correlation analysis showed a moderate positive correlation (ρ = 0.64, P = 0.005) between miR-210-3p expression in plasma and urine. CONCLUSIONS: Urinary miR-210-3p is a promising, non-invasive diagnostic biomarker of PC, including IPMC. TRIAL REGISTRATION: Not applicable.

Evaluation of ventral branches of segment VI portal vein relative to the right hepatic vein in laparoscopic right anterior sectionectomy.

INTRODUCTION: The right intersectional plane and the right hepatic hilum were noted too often exhibit anatomical variations, making difficult the laparoscopic right anterior sectionectomy (LRAS). METHODS: We analyzed the anatomical features employing 3D-CT images of 55 patients, and evaluated these features according to the course of ventral branches of segment VI of the portal vein (PV, P6a) relative to the right hepatic vein (RHV). RESULTS: P6a run on the dorsal side of RHV in 32 patients (58%, Dorsal-P6a) and the ventral side of RHV in 23 (42%, Ventral-P6a). Ventral-P6a had more patients with S6 partially drained by middle hepatic vein (MHV, 39% vs. 0%, P < 0001), the narrower angle between the anterior and posterior branches of PV (73.1° vs. 93.8°, P = 0.006), the wider angle between the RHV and inferior vena cava  (54.3° vs. 44.3°, P < 0.001), and more steeply pitched angle between S6 and S7 along the RHV (140.6° vs. 162.0°, P < 0.001) compared to Dorsal-P6a. CONCLUSION: In LRAS for Dorsal-P6a patients, the transection surface was relatively flat. In LRAS for Ventral-P6a patients, the narrow space between anterior and posterior glissons makes difficult the glissonean approach. The transection plane was steeply pitched, and RHV was partially exposed. S6 was often partially drained to MHV in 39% of the Ventral-P6a patients, which triggers congestion during liver transection of a right intersectional plane after first splitting the confluence of this branch.

Surrogacy of Recurrence-free Survival for Overall Survival as an Endpoint of Clinical Trials of Perioperative Adjuvant Therapy in Hepatobiliary-pancreatic Cancers: A Retrospective Study and Meta-analysis.

OBJECTIVE: To assess the correlation between recurrence-free survival (RFS) and overall survival (OS) in the hepato-biliary-pancreatic (HBP) surgical setting in order to validate RFS as a surrogate endpoint. SUMMARY BACKGROUND DATA: Reliable surrogate endpoints for OS are still limited in the field of HBP surgery. METHODS: We analyzed patients who underwent curative resection for HBP disease (986 patients with pancreatic ductal adenocarcinoma [PDAC], 1168 with biliary tract cancer [BTC], 1043 with hepatocellular carcinoma [HCC], and 1071 with colorectal liver metastasis [CRLM]) from September 2002 to June 2022. We also conducted meta-analyses of randomized controlled trials of neoadjuvant or adjuvant therapy to validate the surrogacy in PDAC and BTC. RESULTS: Correlation coefficients between RFS and OS were low for HCC (ρ = 0.67) and CRLM (ρ = 0.53) but strong for PDAC (ρ = 0.80) and BTC (ρ = 0.75). In a landmark analysis, the concordance rates between survival or death at 5 years postoperatively and the presence or absence of recurrence at each time point (1, 2, 3, and 4 y) were 50%, 70%, 74%, and 77% for PDAC and 54%, 67%, 73%, and 78% for BTC, respectively, both increasing and reaching a plateau at 3 years. In a meta-analysis, the correlation coefficients for the RFS hazard ratio and OS hazard ratio in PDAC and BTC were ρ = 0.88 (P < 0.001) and ρ = 0.87 (P < 0.001), respectively. CONCLUSION: Three-year RFS can be a reliable surrogate endpoint for OS in clinical trials of neoadjuvant or adjuvant therapy for PDAC and BTC.

Overview and clinical significance of multiple mutations in individual genes in hepatocellular carcinoma.

BACKGROUND: Multiple mutation (MM) within a single gene has recently been reported as a mechanism involved in carcinogenesis. The present study investigated the clinical significance of MMs in hepatocellular carcinoma (HCC). METHODS: Two hundred twenty-three surgically resected HCCs were subjected to gene expression profiling and whole-exome sequencing. RESULTS: MMs in individual genes were detected in 178 samples (MM tumors: 79.8%). The remaining samples all carried a single mutation (SM tumors: 20.2%). Recurrence-free survival in the MM group was significantly worse in comparison to the SM group (P = 0.012). A Cox proportional hazard analysis revealed that MM tumor was an independent predictor for worse a prognosis (hazard ratio, 1.72; 95% confidence interval, 1.01-3.17; P = 0.045). MMs were frequently observed across in various genes, especially MUC16 (15% of samples had at least one mutation in the gene) and CTNNB1 (14%). Although the MUC16 mRNA expression of MUC16 wild-type and MUC16 SM tumors did not differ to a statistically significant extent, the expression in MUC16 MM tumors was significantly enhanced in comparison to MUC16 SM tumors (P < 0.001). In MUC16, MMs were associated with viral hepatitis, higher tumor marker levels and vascular invasion. The MUC16 MMs group showed significantly worse recurrence-free survival in comparison to the MUC16 SM group (P = 0.022), while no significant difference was observed between the MUC16 SM group and the MUC16 wild-type group (P = 0.324). CONCLUSIONS: MM was a relatively common event that may occur selectively in specific oncogenes and is involved in aggressive malignant behavior.

The clinical benefits of performing staging laparoscopy for pancreatic cancer treatment.

BACKGROUND: The indications and benefits derived from staging laparoscopy (SL) for pancreatic cancer (PC) remain controversial. METHODS: This study involved PC patients in whom resection had been considered possible between 2009 and 2020. We classified the patients into before 2014 (training set) and 2014 and later (validation set) groups, as SL was introduced in 2014, in our institution. In the training set, the predictors of non-curative factors were investigated, and reproducibility was confirmed in the validation set. In addition, the outcomes were compared between the datasets. RESULTS: A total of 802 patients were classified into the training set (n = 241) and validation set (n = 561). In the training set, pancreatic body or tail tumors (odds ratio [OR]: 2.62: P = 0.039), CA19-9 > 88 U/ml (OR: 3.21: P = 0.018) and a tumor diameter >36 mm (OR: 6.07; P < 0.001) were independent predictors of non-curative factors. The increased rate of non-curative factors was confirmed as the number of predictors increased in the validation set. The curative resection (CR) rate was significantly higher in the validation set than in the training set (P = 0.035). Although there was no significant difference in the OS in the not-resected group (P = 0.895), the OS in the CR and non-CR group was significantly better in the validation set than in the training set (CR, P < 0.001; non-CR, P < 0.001). CONCLUSION: The findings suggest potential candidates for SL and revealed improved outcomes by the advent of treatment strategies including SL.

Reconsidering the Optimal Regional Lymph Node Station According to Tumor Location for Pancreatic Cancer.

BACKGROUND: A consensus regarding the optimal extent of lymph node dissection for pancreatic cancer has not yet been achieved. The purpose of this study was to evaluate the efficacy of lymph node dissection according to the location for pancreatic cancer. METHODS: A total of 495 patients diagnosed with invasive ductal carcinoma of the pancreas who had undergone a pancreatectomy between October 2002 and December 2015 were analyzed. The efficacy index (EI) was calculated for each lymph node station via multiplication of the frequency of metastasis to the station and the 5-year survival rate of the patients with metastasis to that station. RESULTS: For pancreatic head (Ph) tumors, mesocolon lymph nodes had a high EI, although not regional. For pancreatic body (Pb) tumors, peri-Ph lymph nodes had a high EI, although not regional. For pancreatic tail (Pt) tumors, lymph nodes along the celiac axis and common hepatic artery had a zero EI, although regional. When the Ph was segmented into the pancreatic neck (Ph-neck), uncinate process (Ph-up), and periampullary regions, hepatoduodenal ligament lymph nodes had a zero EI for Ph-up, although regional; the mesojejunum lymph node also had a zero EI, even for Ph-up, regardless of a high incidence of metastasis. Regarding lymph node recurrence after surgery, recurrence was most frequently found at the peri-Ph lymph node (12%) in patients with Pb tumors who had undergone a distal pancreatectomy. CONCLUSIONS: The optimal extent of lymph node dissection should be estimated in regard to the tumor location.

Clinical Significance of Preoperative Albumin-Bilirubin Grade in Pancreatic Cancer.

BACKGROUND: No study has clarified the clinical significance of albumin-bilirubin (ALBI) grade in a large cohort of pancreatic cancer patients. METHODS: A total of 1006 consecutive patients diagnosed with pancreatic cancer and deemed eligible for surgical resection were analyzed. The ALBI score was calculated as: ALBI score = (log10 bilirubin [µmol/L] × 0.66) + (albumin [g/L] × - 0.0852). ALBI grade was assigned as grade 1, 2a, 2b, and 3. ALBI grade 1 was assigned to the ALBI low group (N = 566), and grades 2a, 2b, and 3 to the ALBI high group (N = 440). RESULTS: The primary lesion could not be resected in 129 patients. Among all patients, overall survival (OS) was significantly worse in the ALBI high group than in the ALBI low group (P = 0.024). Overall, 877 patients underwent pancreatectomy. In these patients, the ALBI high group was associated with high CA19-9 level (P < 0.001), lower morbidity rate (P < 0.001), and pancreatic head tumor (P = 0.001). Patients' OS after resection was significantly worse in the ALBI high group than in the ALBI low group (P < 0.001). Cox proportional hazard analysis revealed ALBI grade as an independent predictor for prognosis (hazard ratio, 1.33; P = 0.015). Even in the CA19-9 negative patients, OS was significantly worse in the ALBI high group than in the ALBI low group (P = 0.046). CONCLUSIONS: The ALBI grade is a clinically useful predictor for prognosis in pancreatic cancer patients.

The Prognostic Relevance of the Number and Location of Positive Lymph Nodes for Ampulla of Vater Carcinoma.

BACKGROUND: Lymph node metastasis (LNM) has been regarded as one of the prognostic factors in patients with ampulla of Vater carcinoma (AC). However, the consensus about an optimal cutoff value of the number of LNMs and the definition of the regional lymph nodes (RLNs) has not been achieved. METHODS: This study included 114 consecutive patients who underwent pancreatoduodenectomy for AC between January 2002 and March 2019. RESULTS: The minimum p value approach for the greatest difference in the overall survival classified the number of LNM into none (N0, n = 66), from 1 to 2 (N1, n = 32), and ≥3 LNM (N2, n = 11) (p = 0.004). Distant LNM was defined as M1 (n = 5). Significant differences in relapse-free survival (RFS) were found between N0 and N1 (p < 0.001), N1 and N2 (p = 0.047), and N1 and M1 (p = 0.044) but not between N2 and M1 (p = 0.683). Moreover, the patients with regional LNM were classified into two groups: Np group (n = 35, LNM only in pancreatic head region) and Nd group (n = 8, LNM in other regional location). Significant differences in the RFS were found between N0 and Np (p < 0.001), Np and Nd (p = 0.004), and Np and M1 (p = 0.033) but not between Nd and M1 (p = 0.883). A Cox proportional hazards analysis for RFS revealed that ≥ 3 LNMs (hazards ratio [HR], 3.22) and LNM except for pancreatic head region (HR, 4.27) were individually independent worse prognostic factors. CONCLUSIONS: ≥3 LNMs and regional LNM except for pancreatic head region were associated with poor prognosis comparable to that of the patients with M1.

Prognostic impact of abutment to the branches of the superior mesenteric artery in borderline resectable pancreatic cancer.

PURPOSE: The clinical impact of abutment to an artery and its branch on resectability and prognosis in patients with borderline resectable pancreatic cancer is unclear. METHODS: Patients diagnosed with borderline resectable pancreatic cancer due to artery abutment between April 2012 and December 2018 were enrolled. Contact between arteries and the tumour was assessed by computed tomography (CT). RESULTS: A primary lesion was resected in 63 patients (R group) and unresected in 19 patients (UR group). Overall survival (OS) was worse in the UR group than in the R group (P < 0.001). Multivariate analysis showed that abutment to the superior mesenteric artery (SMA) branches (P = 0.001) was an independent predictor of poor OS after surgery. Regarding the initial recurrence pattern, abutment to the SMA branches was significantly associated with high incidence of distant metastasis (P < 0.001). According to the most distal SMA branch attached on CT, significant differences in RFS were found between absent-J1A (P = 0.017), J2A-J3A (P = 0.0313) and J3A-middle colic artery (MCA, P = 0.0476) but not between J1A-J2A (P = 0.8207). Significant prognostic differences in OS after initiation of the treatment were found between absent-J1A/J2A (P = 0.006) and J1A/J2A-J3A/MCA (P = 0.033) but not between J3A/MCA-UR (P = 0.494). CONCLUSION: Abutment to the SMA branches was associated with high incidence of distant metastasis after resection and a poor survival. Especially, abutment to the J3A or MCA was associated with poor prognosis comparable with that of the UR group.

Low levels of tumour suppressor miR-655 in plasma contribute to lymphatic progression and poor outcomes in oesophageal squamous cell carcinoma.

Recent studies identified that low levels of tumour suppressor microRNAs (miRNAs) in plasma/serum relate to tumour progression and poor outcomes in cancers. We selected six candidates (miR-126, 133b, 143, 203, 338-3p, 655) of tumour suppressor miRNAs in oesophageal squamous cell carcinoma (ESCC) by a systematic review of NCBI database. Of these, miR-655 levels were significantly down-regulated in plasma of ESCC patients compared to healthy volunteers by test- and validation-scale analyses. Low levels of plasma miR-655 were significantly associated with lymphatic invasion, lymph node metastasis and advanced stage. Univariate and multivariate analysis revealed that the low level of plasma miR-655 was an independent risk factor of lymphatic progression and a poor prognostic factor. Overexpression of miR-655 in ESCC cells inhibited cell proliferation, migration, invasion and epithelial-mesenchymal transition. Increased plasma miR-655 levels by the subcutaneous injection significantly inhibited lymph node metastasis in mice. Low levels of miR-655 in plasma relate to lymphatic progression and poor outcomes, and the restoration of the plasma miR-655 levels might inhibit tumour and lymphatic progression in ESCC.

The Prognostic Relevance of the New 8th Edition of the Union for International Cancer Control Classification of TNM Staging for Ampulla of Vater Carcinoma.

OBJECTIVE: The aim of this study was to investigate the clinical relevance of the 8th edition of the Union for International Cancer Control classification of TNM staging for ampulla of Vater carcinoma (AC). METHODS: A total of 104 consecutive patients who underwent macroscopic curative resection for AC between January 2002 and September 2017 were investigated. RESULTS: Significant differences in recurrence-free survival (RFS) were found between T1a and T1b (p = 0.0030), but not between T1b and T2 (p = 0.9319), T2 and T3a (p = 0.0732), or T3a and T3b (p = 0.2118). The prognostic impact of the depth of duodenal invasion and pancreatic invasion, which define the T category, were evaluated. With regard to duodenal invasion, significant differences in RFS were found between the negative and submucosa classifications (p = 0.0012) and the muscularis propria and serosa classifications (p = 0.0131), but not between the submucosa and muscularis propria classifications (p = 0.6390). With regard to pancreatic invasion, significant differences in RFS were found between the negative and ≤ 0.5 cm classifications (p = 0.0001), and ≤ 0.5 cm and > 0.5 cm classifications (p = 0.0062). A Cox proportional hazard analysis for RFS revealed that duodenal invasion (submucosa or muscularis propria/negative, hazard ratio [HR] 5.08; serosa/negative, HR 7.42), and pancreatic invasion (≤ 0.5 cm/negative, HR 8.23; > 0.5 cm/negative, HR 9.81) were independent prognostic factors. An alternative new T category was proposed, based on the HRs, as follows: T1, tumor limited to the ampulla of Vater or sphincter of Oddi; T2, duodenal invasion (submucosa or muscularis propria); T3, pancreatic invasion (≤ 0.5 cm) or duodenal invasion (serosa); and T4, pancreatic invasion (> 0.5 cm). This alternative T category can well classify each subgroup with prognostic differences. CONCLUSIONS: Reconsideration of the T category based on the prognostic impact of TNM factors, including the depth of duodenal and pancreatic invasion, are required in the 8th edition T category.

Infrahepatic Inferior Vena Cava Semi-Clamping can Reduce Blood Loss During Hepatic Resection but Still Requires Monitoring to Avoid Acute Kidney Injury.

BACKGROUND: The efficacy of infrahepatic inferior vena cava (IVC) semi-clamping for reducing blood loss during hepatic resection and its safety remain unclear. The aim of this study was to validate the effectiveness of IVC semi-clamping for reducing blood loss during hepatic resection and to confirm its safety. METHODS: Patients who underwent anatomical hepatic resection between January 2011 and May 2018 were analysed by propensity score-matched and multivariate analyses. RESULTS: Of 437 patients who underwent anatomical hepatic resection, IVC semi-clamping was performed in 196 patients (44.9%; clamping group). A propensity score-matched analysis demonstrated that even though there was no significant difference in the characteristics of the 141 patients in each group, IVC semi-clamping reduced the blood loss during hepatic resection (clamping group versus non-clamping group: 836 ± 123 vs. 1198 ± 124 ml, P = 0.04). Regarding post-operative complications, the multivariate analysis identified IVC semi-clamping as an independent risk factor for acute kidney injury on post-operative day 1 (P = 0.01, odds ratio = 9.23). A significant positive correlation was found between the duration of IVC semi-clamping and an increased level of serum creatinine (sCre) (P = 0.03), and a significant inverse correlation was found between the blood pressure after clamping and an increased level of sCre (P = 0.02). A receiver operating characteristic analysis revealed the duration and mean blood pressure after clamping that indicated a high risk of acute kidney injury to be 116 min and 65 mmHg, respectively. CONCLUSION: IVC semi-clamping can reduce blood loss during hepatic resection but still necessitates monitoring in order to avoid acute kidney injury.

Overexpression of ZRF1 is related to tumor malignant potential and a poor outcome of gastric carcinoma.

Zuotin-related factor 1 (ZRF1) is a recently characterized epigenetic factor involved in transcriptional regulation and is highly overexpressed in several malignancies, but it is not known whether it plays a role in gastric cancer (GC). In this study, we investigated whether ZRF1 acts as a cancer-promoting gene through its activation/overexpression in GC. We analyzed five GC cell lines and 133 primary tumors, which had been curatively resected in our hospital between 2001 and 2003. Overexpression of ZRF1 was detected in GC cell lines (four out of five lines, 80.0%) and was detected in primary tumor samples of GC (52 out of 133 cases, 39.1%) and significantly correlated with differentiated histological type, venous invasion, lymphatic invasion, advanced stage and a higher recurrence rate. ZRF1-overexpressing tumors had a worse survival rate than those with non-expressing tumors (P < 0.01, log-rank test). ZRF1 positivity was independently associated with a worse outcome in the multivariate analysis (P < 0.01; hazard ratio 4.92; 95% confidence interval: 1.6-21.1). In ZRF1-overexpressing GC cells, knockdown of ZRF1 using specific siRNAs inhibited the cell proliferation, migration and invasion and induced apoptosis in a p53-dependent manner. These findings suggest that ZRF1 plays a crucial role in tumor malignant potential through its overexpression and highlight its usefulness as a prognostic factor and potential therapeutic target in GC.

Venous invasion as a risk factor for recurrence after gastrectomy followed by chemotherapy for stage III gastric cancer.

BACKGROUND: Although adjuvant chemotherapy with S-1 after curative gastrectomy has been performed as a standard treatment for Stage II and III gastric cancer (GC) in Japan, patients with Stage III GC still have a high incidence of recurrence and a poor prognostic outcome. The aim of this study was to investigate risk factors for recurrence in patients with Stage III GC despite of curative gastrectomy followed by adjuvant chemotherapy, suggesting an indicator for more intensive management. METHODS: A total of 97 patients with pathological Stage III GC underwent adjuvant chemotherapy after curative gastrectomy between 2001 and 2014, were enrolled in this study. We retrospectively analyzed their hospital records from our hospital. RESULTS: The 5-year relapse-free survival (RFS) rates of patients with pStage III GC were 42.0%. Univariate and multivariate analyses for RFS revealed that venous invasion (v+) was an independent factor predicting a shorter RFS (v + vs. v-, 36.5% vs. 47.4%, P = 0.034, HR 1.82, 95% CI: 1.01-3.37). Venous invasion also predicted a shorter overall survival (OS) (v + vs. v-, 33.7% vs. 50.4%, P = 0.027). Regarding the patterns of recurrence, hematogenous recurrence was significantly occurred in patients with v + GC than those without (P = 0.022). CONCLUSIONS: Stage III GC with venous invasion is a high-risk subgroup for hematogenous recurrence after curative surgery followed by adjuvant chemotherapy. More intensive and effective adjuvant chemo and/or molecular targeted therapy for Stage III GC patients with venous invasion should be considered to improve their outcomes.

Reconstruction method as an independent risk factor for postoperative bone mineral density loss in gastric cancer.

BACKGROUND AND AIM: No study has compared the incidence of postoperative bone metabolic disorders between Billroth-I (B-I) and Roux-en-Y (R-Y) reconstructions after distal gastrectomy (DG) for gastric cancer (GC). In this study, we wished to examine the impact of reconstruction method on postoperative bone mineral density (BMD) loss. METHODS: We investigated a total of 148 consecutive patients who underwent DG with B-I or R-Y reconstruction for stage I GC between 2008 and 2012. We retrospectively assessed the BMD data using computed tomography attenuation values of the first lumbar vertebra after surgery. RESULTS: In multivariate analysis for the whole study series, R-Y reconstruction was identified as an independent risk factor for BMD loss after DG (P < 0.0001; OR = 5.60; 95% CI = 2.38-13.98). Propensity score match analysis was used to overcome bias because of the different covariates for the two groups; even though the 37 patients in the B-I group and the 37 patients in the R-Y group had no significant difference among characteristics, B-I reconstruction was validated to have superiority over R-Y reconstruction for preventing BMD loss in the first 3 years after DG. The cumulative hazard ratio of osteoporosis after gastrectomy was significantly higher in the R-Y group than in the B-I group (P = 0.0427). CONCLUSIONS: Billroth-I reconstruction might be a preferable method for preventing BMD loss after gastrectomy in GC patients.

Overexpression of PBK/TOPK relates to tumour malignant potential and poor outcome of gastric carcinoma.

BACKGROUND: PDZ-binding kinase/T-LAK cell-originated protein kinase (PBK/TOPK) is a serine-threonine kinase and overexpressed in various types of cancer by inhibiting the transactivation activities of p53 and PTEN. We tested whether PBK/TOPK acts as a cancer-promoting gene through its activation/overexpression in gastric cancer (GC). METHODS: We analysed five GC cell lines and 144 primary tumours, which were curatively resected in our hospital between 2001 and 2003. RESULTS: Overexpression of the PBK/TOPK protein was frequently detected in GC cell lines (4 out of 5 lines, 80.0%) was detected in primary tumour samples of GC (24 out of 144 cases, 16.6%) and was significantly correlated with venous invasion, tumour depth and recurrence rate. PDZ-binding kinase/T-LAK cell-originated protein kinase-overexpressing tumours had a worse survival rate than those with non-expressing tumours (P=0.0009, log-rank test). PDZ-binding kinase/T-LAK cell-originated protein kinase positivity was independently associated with a worse outcome in multivariate analysis (P<0.0001, hazard ratio 6.40 (2.71-14.49)). In PBK/TOPK-overexpressing GC cells, knockdown of PBK/TOPK inhibited the cell proliferation through the p53 activation in a TP53 mutation-dependent manner and inhibited the migration/invasion through the PTEN upregulation in a TP53 mutation-independent manner. CONCLUSIONS: These findings suggest PBK/TOPK plays a crucial role in tumour malignant potential through its overexpression and highlight its usefulness as a prognostic factor and potential therapeutic target in GC.