Removal of gemcitabine-induced senescent cancer cells by targeting glutaminase1 improves the therapeutic effect in pancreatic ductal adenocarcinoma.

Insufficient cancer treatment can induce senescent cancer cell formation and treatment resistance. The characteristics of induced senescent cancer (iSnCa) cells remain unclear. Pancreatic ductal adenocarcinoma (PDAC) has a low and nondurable response rate to current treatments. Our study aimed to analyze the properties of iSnCa cells and the relationship between cellular senescence and prognosis in PDAC. We evaluated the characteristics of gemcitabine-induced senescent cancer cells and the effect of senescence-associated secretory phenotype (SASP) factors released by iSnCa cells on surrounding PDAC cells. The relationship between cellular senescence and the prognosis was investigated in 50 patients with PDAC treated with gemcitabine-based neoadjuvant chemotherapy. Exposure to 5 ng/mL gemcitabine-induced senescence, decreased proliferation and increased senescence-associated ß-galactosidase-cell staining without cell death in PDAC cells; the expression of glutaminase1 (GLS1) and SASP factors also increased and caused epithelial-mesenchymal transition in surrounding PDAC cells. iSnCa cells were selectively removed by the GLS1 inhibitor bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl)ethyl sulfide (BPTES) through apoptosis induction. Cellular senescence was induced in PDAC cells via insufficient gemcitabine in subcutaneous tumor model mice. GLS1 expression was an independent prognostic factor in patients with PDAC who received gemcitabine-based neoadjuvant chemotherapy. This is the first study to identify the relationship between senescence and GLS1 in PDAC. Low-dose gemcitabine-induced senescence and increased GLS1 expression were observed in PDAC cells. Cellular senescence may contribute to treatment resistance of PDAC, hence targeting GLS1 in iSnCa cells may improve the therapeutic effect.

KLK10 derived from tumor endothelial cells accelerates colon cancer cell proliferation and hematogenous liver metastasis formation.

Tumor endothelial cells (TECs), which are thought to be structurally and functionally different from normal endothelial cells (NECs), are increasingly attracting attention as a therapeutic target in hypervascular malignancies. Although colorectal liver metastasis (CRLM) tumors are hypovascular, inhibitors of angiogenesis are a key drug in multidisciplinary therapy, and TECs might be involved in the development and progression of cancer. Here, we analyzed the function of TEC in the CRLM tumor microenvironment. We used a murine colon cancer cell line (CT26) and isolated TECs from CRLM tumors. TECs showed higher proliferation and migration than NECs. Coinjection of CT26 and TECs yielded rapid tumor formation in vivo. Immunofluorescence analysis showed that coinjection of CT26 and TECs increased vessel formation and Ki-67+ cells. Transcriptome analysis identified kallikrein-related peptide 10 (KLK10) as a candidate target. Coinjection of CT26 and TECs after KLK10 downregulation with siRNA suppressed tumor formation in vivo. TEC secretion of KLK10 decreased after KLK10 downregulation, and conditioned medium after KLK10 knockdown in TECs suppressed CT26 proliferative activity. Double immunofluorescence staining of KLK10 and CD31 in CRLM tissues revealed a significant correlation between poor prognosis and positive KLK10 expression in TECs and tumor cells. On multivariate analysis, KLK10 expression was an independent prognostic factor in disease-free survival. In conclusion, KLK10 derived from TECs accelerates colon cancer cell proliferation and hematogenous liver metastasis formation. KLK10 in TECs might offer a promising therapeutic target in CRLM.

Skeletal Muscle-Derived Irisin Enhances Gemcitabine Sensitivity and Suppresses Migration Ability in Pancreatic Ductal Adenocarcinoma.

BACKGROUND: High skeletal muscle mass might be a prognostic factor for patients with pancreatic ductal adenocarcinoma (PDAC); however, the underlying reason is unclear. We hypothesized that myokines, which are cytokines secreted by the skeletal muscle, function as suppressors of PDAC. We specifically examined irisin, a myokine, which plays a critical role in the modulation of metabolism, to clarify the anticancer mechanisms. METHODS: First, the effect of the conditioned medium (CM) from skeletal muscle cells and from irisin-knockdown skeletal muscle cells on PDAC cell lines was evaluated. We then investigated the effects and anticancer mechanism of irisin in PDAC cells, and evaluated the anticancer effect of recombinant irisin in a PDAC xenograft mouse model. Finally, patients undergoing pancreatic resection for PDAC were divided into two groups based on their serum irisin level, and the long-term outcomes were evaluated. RESULTS: The CM enhanced gemcitabine sensitivity by inducing apoptosis and decreasing cell migration by inhibiting epithelial-mesenchymal transition (EMT) in PDAC cell lines. The CM derived from irisin-knockdown skeletal muscle cells did not affect the PDAC cell lines. The addition of recombinant irisin to PDAC cell lines facilitated sensitivity to gemcitabine by inhibiting the mitogen-activated protein kinase (MAPK) pathway, and decreased migration by inhibiting EMT via the transforming growth factor-ß/SMAD pathway. Xenografts injected with gemcitabine and recombinant irisin grew slower than the xenografts injected with gemcitabine alone. The overall survival was prolonged in the high-irisin group compared with that in the low-irisin group. CONCLUSIONS: Skeletal muscle-derived irisin may affect PDAC by enhancing its sensitivity to gemcitabine and suppressing EMT.

Results of a Randomized Clinical Study of Gemcitabine Plus Nab-Paclitaxel Versus Gemcitabine Plus S-1 as Neoadjuvant Chemotherapy for Resectable and Borderline Resectable Pancreatic Ductal Adenocarcinoma (RCT, CSGO-HBP-015).

BACKGROUND: The optimal neoadjuvant chemotherapy (NAC) regimen for patients with localized pancreatic ductal adenocarcinoma (PDAC) remains uncertain. This trial aimed to evaluate the efficacy and safety of two neoadjuvant chemotherapy (NAC) regimens, gemcitabine plus nab-paclitaxel (GA) and gemcitabine plus S-1 (GS), in patients with resectable/borderline-resectable (R/BR) PDAC. PATIENTS AND METHODS: Treatment-naïve patients with R/BR-PDAC were enrolled and randomly allocated. They received two cycles (2 months) of each standard protocol, followed by radical surgery for those without tumor progression in general hospitals belonging to our intergroup. The primary endpoint was to determine the superior regimen on the basis of achieving a 10% increase in the rate of patients with progression-free survival (PFS) at 2 years from allocation. RESULTS: A total of 100 patients were enrolled, with 94 patients randomly assigned to the GS arm (N = 46) or GA arm (N = 48). The 2-year PFS rates did not show the stipulated difference [GA, 31% (24-38%)/GS, 26% (18-33%)], but the Kaplan-Myer analysis showed significance (median PFS, GA/GS 14 months/9 months, P = 0.048; HR 0.71). Secondary endpoint comparisons yielded the following results (GA/GS arm, P-value): rates of severe adverse events during NAC, 73%/78%, P = 0.55; completion rates of the stipulated NAC, 92%/83%, P = 0.71; resection rates, 85%/72%, P = 0.10; average tumor marker (CA19-9) reduction rates, -50%/-21%, P = 0.01; average numbers of lymph node metastasis, 1.7/3.2, P = 0.04; and median overall survival times, 42/22 months, P = 0.26. CONCLUSIONS: This study found that GA and GS are viable neoadjuvant treatment regimens in R/BR-PDAC. Although the GA group exhibited a favorable PFS outcome, the primary endpoint was not achieved.

Apparent diffusion coefficient in intrahepatic cholangiocarcinoma diffusion-weighted magnetic resonance imaging noninvasively predicts Ki-67 expression.

AIM: Tumor Ki-67 expression reflects prognosis and cancer grade, and biopsy-based preoperative assessment of Ki-67 expression is key to treatment. Apparent diffusion coefficient (ADC) values obtained with this imaging may noninvasively predict Ki-67 by reflecting tumor cell density and limited water molecule movement from irregular alignment. This study aimed to investigate the ability of ADC values to predict Ki-67 expression in intrahepatic cholangiocarcinoma (ICC). METHOD: We retrospectively analyzed 39 cases of ICC confirmed by surgical pathology. All patients had undergone magnetic resonance imaging, and ADC values (mean, minimum, and maximum) were calculated. Ki-67 expression was assessed by immunohistochemistry, and patients were divided into groups of high (n = 18) and low (n = 21) Ki-67 expression. To assess the diagnostic performance of the ADC values for Ki-67 expression, we used the receiver operating characteristic curve and compared the areas under the curve (AUC). RESULTS: The mean and minimum ADC values were significantly lower in the group with high Ki-67 expression. For predicting high Ki-67 expression, the AUC values were 0.701 for mean ADC, 0.818 for minimum ADC, and 0.571 for maximum ADC. The diagnostic sensitivity and specificity of the minimum ADC values were 88.9% and 76.2%, respectively. In addition, with ADC values combined, the AUC increased to 0.831. Apparent diffusion coefficient is a useful predictor of Ki-67 expression level in ICC. CONCLUSION: Apparent diffusion coefficient values, especially minimum ADC values, can noninvasively predict ICC associated with high Ki-67 expression.

Exploratory prospective, randomized phase II study of neoadjuvant transcatheter arterial chemoembolization plus surgery versus surgery alone for large hepatocellular carcinoma (CSGO-HBP-005): Clinical Study Group of Osaka University, Hepato-Biliary-Pancreatic Group.

AIM: Neoadjuvant transcatheter arterial chemoembolization (TACE) for large tumors is controversial, especially in the minimally invasive surgery era. The aim of this study was to compare features between groups treated with neoadjuvant TACE followed by surgery (TACE + surgery) or upfront surgery for hepatocellular carcinoma >5 cm. METHODS: In this exploratory, multicenter, randomized phase I study, the primary measure was 2-year disease-free survival (DFS). Secondary measures were resection rate, necrosis rate by TACE, 2-year overall survival, and site of recurrence. A total of 30 patients were randomly allocated to each arm. RESULTS: The two arms did not differ in patient characteristics. The median time to surgery from randomization was 48 days for TACE + surgery and 29 for surgery only (p < 0.001). Postoperative morbidities did not differ between arms. The 2-year DFS, overall survival, and resection rates were 56.7%, 80.0%, and 93.3%, respectively, in the TACE + surgery arm, and 56.1%, 89.9%, and 90.0% in the upfront surgery arm. Minimally invasive surgery was carried out in 35.7% in the TACE + surgery arm and in 29.6% in the upfront surgery arm. The median necrosis rate by TACE was 90.0%. In resected specimens, invasion to the hepatic vein was less with TACE + surgery (3.6% vs. 22.2%, p = 0.0380). In cases of 100% necrosis with TACE, 2-year DFS was 100%. Site of recurrence did not differ between groups. CONCLUSION: Neoadjuvant TACE did not improve 2-year DFS, and neoadjuvant TACE allowed delay of surgical treatment without increased morbidity and cancer progress. CLINICAL TRIAL REGISTRATION: UMIN: 000005241.

Automated Analysis for the Prevalence of Cancer-Associated Fibroblasts in Resected Specimens of Intrahepatic Cholangiocarcinoma is a Simple and Reliable Evaluation System.

BACKGROUND: Intrahepatic cholangiocarcinoma (iCCA) has a high recurrence rate and poor prognosis, and chemotherapy options are limited. The prevalence of cancer-associated fibroblasts (CAFs) in iCCA has recently emerged as a prognostic marker and therapeutic target. A method to quantify the expression of CAFs is needed; however, a simple and reliable quantification method has not yet been established. OBJECTIVE: The aim of this study was to establish a simple and reliable method of quantifying CAFs. METHODS: A total of 71 patients with iCCA who underwent curative resection from November 2006 to October 2020 in our hospital were investigated. Immunohistochemistry for alpha-smooth muscle actin (α-SMA) was performed and α-SMA-positive cells were quantified by an automated analysis system (new method) and visually counted (conventional method). The times required for measurement and the prognosis were compared. RESULTS: The results of the quantification of CAFs by the new method were significantly correlated with the results by the conventional method, and the time required for measurement was significantly shorter with the new method. Patients with high-intensity CAFs showed a significantly poorer prognosis in terms of overall survival (OS) and the cumulative hepatic recurrence rate. In addition, high α-SMA levels were a significant risk factor for OS in multivariate analysis. CONCLUSIONS: This new method may contribute to the management of patients with iCCA, not only for the prediction of prognosis of patients with iCCA, but also for the indication of targeted therapy against CAFs.

Change Impact of Body Composition During Neoadjuvant Chemoradiotherapy in Patients with Resectable and Borderline Resectable Pancreatic Ductal Adenocarcinoma Undergoing Pancreatectomy.

BACKGROUND: The change impact of body composition during neoadjuvant therapy on clinical outcomes in patients with pancreatic ductal adenocarcinoma (PDAC) remains unclear. The aim of this study was to investigate the association between changes in body composition during neoadjuvant chemoradiotherapy (NACRT) and postoperative outcomes in patients with PDAC undergoing pancreatectomy, using three-dimensional images. METHODS: We reviewed 66 consecutive patients with resectable/borderline resectable PDAC receiving gemcitabine and S-1 with radiotherapy between April 2010 and June 2016. Body compositions were evaluated pre- and post-NACRT. All patients were hospitalized and supplied with regulated diet during NACRT treatment. RESULTS: Psoas major muscle volume index (PMI), abdominal fat volume index, and visceral fat volume index decreased significantly after NACRT (P < 0.0001, P < 0.0001, P < 0.0001, respectively). The post-NACRT CA19-9 level decreased significantly in the small-PMI-decrease group compared with the large-PMI-decrease group (P = 0.046). Recurrence-free survival (RFS) and overall survival (OS) of the large-PMI-decrease group were significantly poorer than those of the small-PMI-decrease group (P = 0.002, P = 0.006, respectively). On the other hand, there were no significant differences in RFS and OS between groups with high and low PMI, at the point of either pre-NACRT (P = 0.117, P = 0.123, respectively) or post-NACRT (P = 0.065, P = 0.064, respectively). Multivariate analysis identified a large percentage decrease in PMI as an independent risk factor for recurrence and death (P = 0.003, P = 0.002, respectively). CONCLUSIONS: Loss of skeletal muscle mass during NACRT was an independent risk factor for survival in patients with PDAC.

Pancreatic cancer near the splenic hilum has a higher likelihood of splenic vessel invasion and unfavorable survival.

PURPOSE: This study aimed to investigate whether clinical outcomes varied based on the tumor location within the pancreatic body and tail in patients with pancreatic cancer (PC). METHODS: Ninety-five patients who had undergone a distal pancreatectomy for resectable (R) or borderline resectable (BR) PC within the pancreatic body or tail region were retrospectively investigated and divided into four groups (three subgroups of R-PC according to tumor location, and BR-PC): R-PC in the pancreatic body region (group A, n = 24), R-PC on the right side of the pancreatic tail region (group B, n = 17), R-PC on the left side of the pancreatic tail region (group C, n = 29), and BR-PC located in any region within the pancreatic body and tail (group BR, n = 25). RESULTS: Group C patients showed a higher incidence of pretreatment splenic artery and vein involvement than group A and B patients (splenic artery: 8.3/11.8/41.4%, p < 0.010; splenic vein: 25.0/23.5/79.3%, p < 0.010, in groups A/B/C, respectively). The overall survival of group C patients was significantly unfavorable compared to that of group A and B patients (median: 3.9/4.2/2.3 years in groups A/B/C, p = 0.029, respectively). Pretreatment clinical factors were comparable between group C and group BR. Median survival rates were comparable between group C and BR patients (2.3 and 2.0 years, respectively) (p = 0.93). CONCLUSIONS: Differences in anatomical location within the pancreatic body and tail characterize the unfavorable outcomes of PC near the splenic hilum.

Rubicon can predict prognosis in patients with pancreatic ductal adenocarcinoma after neoadjuvant chemoradiotherapy.

BACKGROUND: Despite previous therapeutic studies on autophagy in cancer, its role in the treatment of pancreatic ductal adenocarcinoma remains controversial, especially regarding its effect on chemotherapy, radiotherapy, and both combined. We focused on RUN domain Beclin-1 interacting and cysteine-rich-containing protein (Rubicon) to reveal its contribution to pancreatic ductal adenocarcinoma after chemoradiotherapy. METHODS: To evaluate the clinical significance of Rubicon, immunohistochemistry was performed, and Rubicon expression was analyzed across 81 specimens resected from patients with pancreatic ductal adenocarcinoma after neoadjuvant chemoradiotherapy. A gemcitabine-resistant pancreatic ductal adenocarcinoma cell line was established followed by Rubicon expression and autophagy flux estimation. Finally, gemcitabine sensitivity, invasion ability, and cell viability were evaluated using Rubicon-targeting small interfering RNA. RESULTS: Rubicon expression in resected pancreatic ductal adenocarcinoma samples after chemoradiotherapy revealed significantly worse overall survival and recurrence-free survival in the Rubicon-high expression group than in the Rubicon-low expression group (overall survival: median [years] 2.02 vs. 3.21, p = 0.0359; recurrence-free survival: median [years] 0.90 vs. 1.90, p = 0.0146). In vitro, gemcitabine-resistant pancreatic ductal adenocarcinoma cell lines exhibited higher Rubicon expression and lower autophagy flux than the parental cell line (p < 0.01). Transduction with small interfering RNA downregulated the expression without affecting gemcitabine sensitivity, but it reduced invasion ability and cell viability (p < 0.01) in the gemcitabine-resistant pancreatic ductal adenocarcinoma cell line. CONCLUSIONS: High Rubicon expression is a significant, unfavorable prognostic factor in pancreatic ductal adenocarcinoma after neoadjuvant chemoradiotherapy. Downregulation of Rubicon expression improves invasion ability and cell viability in gemcitabine-resistant pancreatic ductal adenocarcinoma.

[FOLFIRI plus RAM Therapy in Later Line of Unresectable Colorectal Cancer].

FOLFIRI plus ramucirumab(RAM)therapy has been reported to be effective and safe in the RAISE trial as second-line treatment for unresectable colorectal cancer. It is hypothesized that RAM may be effective in patients with PD treated with FOLFIRI plus bevacizumab(Bev)due to different mechanism of action from that of Bev, which is also an angiogenesis inhibitor. From January 2017 to December 2021, we conducted a retrospective study of 6 patients who had PD with 5-FU, oxaliplatin, irinotecan, or Bev as first or second-line treatment at our institution and who received FOLFIRI plus RAM in later line treatment. The 6 cases consisted of 3 patients in the third-line treatment, 1 patient in the fourth-line treatment, and 2 patients in the sixth-line treatment. The anti-tumor effect was PD in all cases in the third-line and fourth-line treatment, but the 2 patients of sixth-line treatment were controlled diseases.

[A Case Report-A Successful Case of Distal Pancreatectomy with En Bloc Celiac Axis Resection for Locally Advanced Pancreatic Cancer with an Aberrant Right Hepatic Artery].

In cases of pancreatic cancer with anatomical variations of the hepatic artery, it is important to evaluate the hemodynamics of each case for surgical indication. We report the case of a 68-year-old man with locally advanced pancreatic cancer and an aberrant right hepatic artery who underwent distal pancreatectomy with celiac axis resection(DP-CAR). He was admitted to our institute due to abdominal discomfort. A CT scan showed pancreatic cancer invading the common hepatic artery. He underwent chemoradiotherapy with a diagnosis of locally advanced pancreatic cancer. After the tumor downstaging, we performed DP-CAR, which included a gastroduodenal artery and a proper hepatic artery resection. Even though delayed gastric emptying was observed after the operation, he was discharged on postoperative day 36.

Tumor endothelial cell-induced CD8+ T-cell exhaustion via GPNMB in hepatocellular carcinoma.

Tumor endothelial cells (TECs) promote tumor angiogenesis and regulate cytotoxic T cells in the tumor microenvironment. However, the roles of TECs for tumor-infiltrating T-cell in hepatocellular carcinoma (HCC) is still unknown. Here, we aimed to investigate how TECs influenced tumor growth and immune responses of HCC focusing on CD8+ T-cell infiltration and exhaustion. First, TECs were isolated from subcutaneous HCC tumors with murine HCC cell lines (BNL-T) with magnetic selection of CD31+ cells, and normal endothelial cells (NECs) were isolated from normal liver. Second, immunocompetent mice were injected with BNL-T alone, BNL-T + NECs, or BNL-T + TECs for tumor formation, and the functions and exhaustion of tumor-infiltrating CD8+ T cells were evaluated. The mice injected with BNL-T + TEC showed rapid tumorigenesis and a decrease in the number of infiltrating CD8+ T cells. In addition, the percentage of CD8+ T-cell exhaustion was significantly higher in tumors from the administration of BNL-T + TEC. Third, the next-generation sequencing on TECs was performed to identify mRNAs that might be a novel treatment target. The molecule of glycoprotein nonmetastatic melanoma protein B (GPNMB) was identified and the functions of GPNMB was analyzed by silencing of GPNMB expression using small interfering RNAs. The silencing of GPNMB expression in TECs induced the suppression of tumor growth and T-cell exhaustion. In conclusion, TECs induced tumor-infiltrating T-cell exhaustion via GPNMB expression and GPNMB might be a novel therapeutic target in HCC.

ACAT-1-Regulated Cholesteryl Ester Accumulation Modulates Gemcitabine Resistance in Biliary Tract Cancer.

BACKGROUND: Biliary tract cancer (BTC) has few choices of chemotherapy, including gemcitabine, therefore exploring the mechanisms of gemcitabine resistance is important. We focused on lipid metabolism because biliary tract epithelial cells are essential in cholesterol and bile acid metabolism and the messenger RNA (mRNA) microarray analysis showed high acyl coenzyme A: cholesterol acyltransferase 1 (ACAT-1) expression in BTC gemcitabine-resistant (GR) cell lines. We hypothesized that aberrant accumulation of cholesteryl ester (CE) regulated by ACAT-1 could modulate GR in BTC. METHODS: CE accumulations were measured in human BTC cell lines, and the relationships between CE levels, ACAT-1 expressions, and gemcitabine sensitivity were analyzed. We performed a small-interfering RNA (siRNA)-mediated knockdown and biochemical inhibition of ACAT-1 in BTC cell lines and alterations of gemcitabine sensitivity were evaluated. To evaluate the clinical significance of ACAT-1 in regard to GR, immunohistochemistry was performed and ACAT-1 expressions were analyzed in resected BTC specimens. RESULTS: CE levels were correlated with ACAT-1 expressions and GR in four human BTC cell lines. siRNA-mediated knockdown of ACAT-1 in two independent GR cell clones as well as ACAT-1 inhibitor treatment significantly increased gemcitabine sensitivity; knockdown of ACAT-1: 5.63- and 8.02-fold; ACAT-1 inhibitor: 8.75- and 9.13-fold, respectively. ACAT-1 expression in resected BTC specimens revealed that the disease-free survival of the ACAT-1 low-intensity group (median 2.3 years) had a significantly better outcome than that of the ACAT-1 high-intensity group (median 1.1 years) under gemcitabine treatment after surgery (*p < 0.05). CONCLUSIONS: Our findings suggest that CE and ACAT-1 might be a novel therapeutic target for GR in BTC.

Inhibition of Clusterin Represses Proliferation by Inducing Cellular Senescence in Pancreatic Cancer.

BACKGROUND: The outcome of pancreatic ductal adenocarcinoma (PDAC) is unsatisfactory, and the identification of novel therapeutic targets is urgently needed. Clinical studies on the antisense oligonucleotide that targets clusterin (CLU) expression have been conducted and have shown efficacy in other cancers. We aimed to investigate the effects of CLU in PDAC and the underlying mechanisms with a view to the clinical application of existing drugs. METHODS: We knocked down CLU in PDAC cells and evaluated changes in cell proliferation. To elucidate the mechanism responsible for these changes, we performed western blot analysis, cell cycle assay, and senescence-associated ß-galactosidase (SA-ß-gal) staining. To evaluate the clinical significance of CLU, immunohistochemistry was performed, and CLU expression was analyzed in specimens resected from PDAC patients not treated with preoperative chemotherapy. RESULTS: Knockdown of CLU significantly decreased cell proliferation and did not induce apoptosis, but did induce cellular senescence by increasing the percentage of G1-phase and SA-ß-gal staining-positive cells. A marker of DNA damage such as γH2AX and factors related to cellular senescence, such as p21 and the senescence-associated secretory phenotype, were upregulated by knockdown of CLU. CLU expression in resected PDAC specimens was located in the cytoplasm of tumor cells and revealed significantly better recurrence-free survival and overall survival in the CLU-low group than in the CLU-high group. CONCLUSIONS: We identified that CLU inhibition leads to cellular senescence in PDAC. Our findings suggest that CLU is a novel therapeutic target that contributes to the prognosis of PDAC by inducing cellular senescence.

Pancreatic CT density is an optimal imaging biomarker for earlier detection of malignancy in the pancreas with intraductal papillary mucinous neoplasm.

BACKGROUND: Intraductal papillary mucinous neoplasms (IPMNs) are typically detected as incidental findings by computed tomography (CT); however, the conventional surveillance is not valid for the early detection of concomitant pancreatic cancer. The pancreas of IPMN is often accompanied by fatty infiltration in the parenchyma, and pancreatic fatty infiltration could be evaluated by pancreatic CT density (pancreatic index, PI). We aimed to investigate whether PI could be an imaging biomarker for the early prediction of malignancies in the pancreas with IPMN. METHODS: Two different cohorts were investigated. (Investigation cohort): A total of 1137 patients with initially low-risk IPMN were compensated by initial IPMN findings, and 2 groups (malignancy/possible benign, 50 cases each) were investigated for yearly changes in PI and for the cutoff value of PI indicating the development of malignancies. (Validation cohort): To validate the cutoff value, 256 patients radiologically suspected of having IPMNs were investigated. RESULTS: (Investigation-cohort): The malignancy group showed a gradual decrease in PI every year, and PI significantly differed among the 2 groups 1 year prior to the last investigation. The cutoff value of PI was set at 0.65. (Validation-cohort): A total of 55% of the patients with a PI below the cutoff value had malignancy in the pancreas, including concomitant pancreatic cancer, and the cutoff value was the most significant risk factors for the development of malignancies in the pancreas compared to the conventional risk factors for IPMN. CONCLUSIONS: Decreasing PI would be an optimal imaging biomarker for earlier detection of malignancies in the pancreas with IPMN.

Long-term outcomes of single-incision versus multiport laparoscopic colectomy for colon cancer: results of a propensity score-based analysis.

BACKGROUND: Long-term outcomes of single-incision laparoscopic colectomy (SILC) for colon cancer (CC), as practiced in real-world settings, especially in relation to disease stage, have not been established. We examined, retrospectively, both short- and long-term outcomes of SILC versus those of multiport laparoscopic colectomy (MPLC) performed for CC in a propensity-score-matched cohort. METHODS: The study involved 263 patient pairs matched 1:1 from among 691 patients who, between January 2008 and May 2014, underwent either SILC or MPLC for a primary solitary CC at our hospital. Short-term and long-term operative outcomes were compared between the two groups. RESULTS: Operation time was the only surgical outcome that varied significantly between the two groups (p = 0.0004). Overall 5-year cancer-specific survival (CSS) in the SILC group was 93.7 (95% CI 89.6-96.2)%, and CSS per pathological stage (I, II and III) was 98.5 (90.0-99.8)%, 96.0 (88.2-98.7)%, and 88.3 (79.6-93.6)%, respectively, whereas overall 5-year CSS in the MPLC group was 93.3 (89.4-95.9)%, and CSS per pathological stage was 100%, 95.4 (88.3-98.3)%, and 84.1 (74.1-90.8)% (p = 0.5278, 0.2679, 0.7666, and 0.9073), respectively. Overall 3-year disease-free survival (DFS) in the SILC group was 94.0 (90.2-96.4)%, and 3-year DFS per pathological stage was 98.6 (90.4-99.8)%, 90.1 (81.4-95.0)%, and 79.0 (69.4-86.2)%, respectively, whereas overall 3-year DFS in the MPLC group was 93.2 (89.4-95.7)%, and 3-year DFS per pathological disease stage was 100%, 94.5 (87.4-97.7)% and 75.5 (64.7-83.8)% (p = 0.2829, 0.7401, 0.4335 and 0.8518), respectively. Thus, oncological outcomes did not differ significantly between groups. Incisional hernia occurred in 21 (8.0%) SILC group patients and 17 (6.5%) MPLC group patients, without a significant between-group difference (p = 0.6139). CONCLUSION: Our data indicate that perioperative and oncological outcomes of SILC performed for CC are comparable to those of MPLC performed for CC.

Clinical Significance of Acylphosphatase 1 Expression in Combined HCC-iCCA, HCC, and iCCA.

BACKGROUND: Combined hepatocellular and cholangiocarcinoma is a rare primary liver cancer with histological features of both hepatocellular carcinoma and intrahepatic cholangiocarcinoma. Little is known about the prognostic features and molecular mechanism of cHCC-iCCA. Acylphosphatase 1 is a cytosolic enzyme that produces acetic acid from acetyl phosphate and plays an important role in cancer progression. AIMS: We evaluated the clinical significance of ACYP1 expression in cHCC-iCCA, HCC, and iCCA. METHODS: ACYP1 immunohistochemistry was performed in 39 cases diagnosed with cHCC-iCCA. The prognosis was evaluated in three different cohorts (cHCC-iCCA, HCC, and iCCA). The relationships between ACYP1 expression and cell viability, migration, invasiveness, and apoptosis were examined using siRNA methods in vitro. In vivo subcutaneous tumor volumes and cell apoptosis were evaluated after downregulation of ACYP1 expression. RESULTS: Almost half of the patients with cHCC-iCCA were diagnosed with high ACYP1 expression. In all three cohorts, the cases with high ACYP1 expression had significantly lower overall survival, and high ACYP1 expression was identified as an independent prognostic factor. Downregulation of ACYP1 reduced the proliferative capacity, migration, and invasiveness of both HCC and iCCA cells. Moreover, knockdown of ACYP1 increased the ratio of apoptotic cells and decreased the expression of anti-apoptosis proteins. In vivo tumor growth was significantly inhibited by the transfection of ACYP1 siRNA, and the number of apoptotic cells increased. CONCLUSION: High ACYP1 expression could influence the prognosis of cHCC-iCCA, HCC, and iCCA patients. In vitro ACYP1 expression influences the tumor growth and cell viability in both HCC and iCCA by regulating anti-apoptosis proteins.

Prognostic value of functional SMAD4 localization in extrahepatic bile duct cancer.

BACKGROUND: SMAD4 is a key mediator of TGFß signaling and one of the mutated genes in extrahepatic bile duct cancer (eBDC). It has been also reported that SMAD4 has dual functions, in carcinogenesis via silencing and in tumor invasion/metastasis via signaling, depending on tumor stage. We previously visualized more nuclear transitioning functional SMAD4 at the tumor invasion front than the central lesion. So, we investigated the localization of functional SMAD4 (e.g., invasion area or metastasis lesion) and its association with chemotherapy and chemo-radiation therapy. METHODS: We performed SMAD4 immunostaining on 98 resected eBDC specimens and evaluated the presence of the functional form of nuclear SMAD4 at the central lesion, invasion front, and metastatic lymph node. We also examined the influence on chemotherapy after recurrence (n = 33) and neoadjuvant chemo-radiation therapy (NAC-RT, n = 21) and the prognostic value of using retrospective data. RESULTS: In 73 patients without NAC-RT, 8.2% had loss of SMAD4 expression and 23.3% had heterogeneous expression. Patients without SMAD4 expression at any site had significantly poorer overall survival (OS) than other patients (P = 0.014). Expression of SMAD4 at the invasion front was related to better survival (recurrence-free survival [RFS] P = 0.033; OS P = 0.047), and no SMAD4 expression at the metastatic lymph node was related to poorer OS (P = 0.011). The patients who had high SMAD4 expression had poorer prognosis after recurrence (RFS P = 0.011; OS P = 0.056). At the residual cancer in the resected specimen, SMAD4 was highly expressed after NAC-RT (P = 0.039). CONCLUSIONS: Loss of SMAD4 protein expression was a poor prognostic factor in eBDC at resectable stage. However, the intensity of functional SMAD4 in eBDC is a marker of resistance to chemo-radiotherapy and malignant potential at advanced stages.

The blockade of interleukin-33 released by hepatectomy would be a promising treatment option for cholangiocarcinoma.

Interleukin-33 (IL-33), an alarmin released during tissue injury, facilitates the development of cholangiocarcinoma (CCA) in a murine model. However, it is unclear whether IL-33 is associated with human CCA. The aim of this study was to support the following hypothesis: IL-33 is released during hepatectomy for CCA, subsequently facilitating the development of subclinical CCA and eventually leading to recurrent disease. IL-33 expression was assessed in various samples from both humans and mice including resected liver and paired plasma samples collected at hepatectomy and after surgery, and its influences on recurrent disease and patient prognosis were determined. Homogenized human liver samples with high or low IL-33 expression were added to the culture medium of human CCA cells, and the changes in proliferation and migration were evaluated. To examine the effects of inhibiting the IL-33 release induced by hepatectomy, syngraft transplantation of murine CCA cells was performed in C57BL/6J mice with or without IL-33 blockade. The amount of IL-33 released into the plasma during hepatectomy correlated with the background liver expression. High expression of IL-33 in the liver was an independent risk factor for recurrence. Homogenized liver tissue strongly expressing IL-33 increased both the proliferation and migration of tumor cells. Mice who underwent hepatectomy exhibited CCA progression in the remnant liver, whereas blockade of IL-33 during hepatectomy inhibited tumor progression. Thus, we concluded that surgery for CCA with curative intent paradoxically induced IL-33 release, which facilitated CCA recurrence, and anti-IL-33 therapy during hepatectomy might reduce the risk of CCA recurrence.