Search

The regulatory T cells (Treg) with the most potent immunosuppressive activity are the effector Tregs (eTreg) with a CD45RA–Foxp3++CCR4+ phenotype. Adult T-cell leukemia (ATL) cells often share the Treg phenotype and also express CCR4. Although mogamulizumab, a monoclonal antibody to CCR4, shows marked antitumor effects against ATL and peripheral T-cell lymphoma, concerns have been raised that it may induce severe autoimmune immunopathology by depleting eTregs. Here, we present case reports for two patients with ATL who responded to mogamulizumab but developed a severe skin rash and autoimmune brainstem encephalitis. Deep sequencing of the T-cell receptor revealed that ATL cells and naturally occurring Tregs within the cell population with a Treg phenotype can be clearly distinguished according to CADM1 expression. The onset of skin rash and brainstem encephalitis was coincident with eTreg depletion from the peripheral blood, whereas ATL relapses were coincident with eTreg recovery. These results imply that eTreg numbers in the peripheral blood sensitively reflect the equilibrium between antitumor immunity and autoimmunity, and that mogamulizumab might suppress ATL until the eTreg population recovers. Close monitoring of eTreg numbers is crucial if we are to provide immunomodulatory treatments that target malignancy without severe adverse events. Cancer Immunol Res; 4(8); 644–9. ©2016 AACR.

Background Recently, a lot of energy devices in the surgical field, especially in the liver surgery, have been developed, and a fine tip LigaSure™, Dolphin Tip Sealer/Divider (DT-SD) also has been used frequently to dissect liver parenchyma as well as ultrasonically activated device (USAD). However, the utility of this instrument for liver dissection (LD) is still unknown. Moreover, to reduce bleeding during LD, a half-grip technique (HGT) was contrived. We herein report an experimental study in swine model to evaluate the feasibility and effectiveness of HGT using DT-SD for LD. Methods The swine model experiment was carried out under general anesthesia by veterinarians. LD was performed repeatedly by DT-SD with the HGT (Group A, n = 6), or the conventional clamp-crush technique (CCT) (Group B, n = 6), and by variable mode USAD (Group C, n = 6). The dissection length and depth (cm) as well as bleeding volume (g) were measured carefully, and the dissection area (cm2) and speed (cm2/min) were calculated precisely. Histological examinations of the dissection surfaces were also executed. Mann–Whitney’s U test was used for Statistical analyses with variance at a significance level of 0.05. Results Among the three groups, the three averages of dissection lengths were unexpectedly equalized to 8.3 cm. The dissection area (cm2) was 9.9 ± 5.1 in Group A, 9.8 ± 4.7 in Group B, and 9.9 ± 4.5 in Group C. The mean blood loss during LD was 10.6 ± 14.8 g in Group A, 41.4 ± 39.2 g in Group B, and 34.3 ± 39.2 g in Group C. For Group A, the bleeding rate was the least, 0.9 ± 1.0 g/cm2, and the average depth of coagulation was the thickest, 1.47 ± 0.29 mm, among the three groups (p

Cardiac invasion by disseminated lymphoma is detected in as many as 9–24% of lymphoma cases on autopsy [1,2]. By contrast, primary cardiac lymphoma (PCL) is very rare, with a reported incidence of ...

We report a patient who underwent laparoscopic enucleation for a nonfunctioning pancreatic neuroendocrine tumor. The patient was a 55-year-old man who had a 12- × 11-mm tumor close to the main pancreatic duct (MPD) in the pancreatic body. To avoid and detect injury to the main pancreatic duct during operation, a nasopancreatic drainage stent (NPDS) was endoscopically placed prior to the operation. According to the NPDS, the relation between the tumor and MPD was easily identified by laparoscopic ultrasonography during enucleation, thus enabling the resecting line to be determined. Moreover, after enucleation, pancreatography through the NPDS was able to clarify the absence of injury to the MPD. The NPDS was removed postoperatively, and the patient was discharged uneventfully on postoperative day 8. Preoperative placement of the NPDS seems to be a useful option for performing safe laparoscopic enucleation of pancreatic neuroendocrine tumor, especially when the lesion is located close to the MPD.

p53 mutations are relatively rare (∼15%) in mantle cell lymphoma (MCL). Chemotherapeutic agents induce DNA damage, p53 phosphorylation and pro-apoptotic wild-type (WT) p53 signaling, resulting in lymphoma cell death. However, DNA damaging agents may have severe acute toxicities, accelerate clonal evolution and cause therapy-related neoplasms by adding new mutations to the original clones. PPM1D is a serine/threonine phosphatase that negatively regulates key DNA damage response proteins including p53, CHK2, Histone H2AX, and ATM. PPM1D has been thought to be an oncogenic protein. It has been reported that PPM1D is overexpressed or amplified in breast and ovarian cancers. GSK2830371 (GSK) is a PPM1D inhibitor, which binds to a flap subdomain that regulates enzymatic activity of PPM1D and substrate recognition (Nat Chem Biol 2014). Treatment of tumor cells with the inhibitor GSK has been found to increase phosphorylation of PPM1D substrates and cause growth inhibition in tumor cells harboring wild-type p53. We investigated the clinical significance of PPM1D and anti-lymphoma effects of GSK in MCL. The mRNA expression levels in patient samples were determined using Oncomine. Our gene expression analyses showed an increase in PPM1D mRNA expression in MCL samples versus normal naïve B lymphocytes (P = 0.044) that are the normal counterparts of MCL. PPM1D mRNA levels were positively correlated with CCND1 (encoding Cyclin D1) mRNA levels (r = 0.33, P = 0.0014) and proliferation signature averages (r = 0.54, P < 0.0001). Higher PPM1D expression at diagnosis was associated with a poorer prognosis in MCL patients (i.e., a median overall survival of 3.9 years for cases with PPM1D expression in the lowest third and 1.4 years in the highest third, P = 0.0047). These results indicate that PPM1D overexpression has a negative prognostic impact on MCL overall disease survival and that PPM1D is a potential therapeutic target in MCL. A total of 8 MCL (3 p53 WT and 5 mutant) cell lines were treated with GSK. 10 μM GSK inhibited cell growth of p53 WT Z-138, JVM-2 and Granta-519 cells by 68%, 38% and 39%, respectively. p53 mutant cells were relatively resistant to GSK (14.8 ± 4.7% growth inhibition). p53 knockdown de-sensitized Z-138 and JVM-2 cells to GSK-induced apoptosis. GSK increased total and Ser15-phosphorylated p53 levels and p53 targets p21 and PUMA in p53 WT cells. Basal levels of PPM1D and its substrates were not associated with GSK sensitivity among MCL cell lines. Interestingly, GSK enhanced bortezomib-induced apoptosis in a p53-independent manner, partially through activation of p38 signaling; p38 inhibition attenuated the combination effect. Collectively, PPM1D inhibition may offer a novel therapeutic strategy for MCL. Citation Format: Kensuke Kojima, Mariko Yoshimura, Aya Maeda, Hiroaki Kitamura, Yuki Nishida, Shinya Kimura. The PPM1D inhibitor GSK2830371 has p53-dependent anti-lymphoma effects and enhances bortezomib-induced apoptosis in mantle cell lymphoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3730.

Recent interest in improving cosmetic outcomes has led to single-incision laparoscopic surgery (SILS) being performed in a variety of organs. However, this innovative technique has rarely been introduced in pancreatic surgery, as it is considered to be a challenging procedure. We report herein our technique of single-incision laparoscopic distal pancreatectomy with or without splenic preservation.A 2.5-cm intraumbilical mini-laparotomy was made for the placement of a SILS Port as a single access site. The overall procedures were similar to those performed in the standard laparoscopic distal pancreatectomy with multiple trocars. To obtain better exposure of the operative field, we made technical refinements by employing gastric suspension with sutures, the tug-exposure technique, a balloon retractor, and gravity by changing the patient's position. The pancreas was transected with a linear stapler, and the specimen was extracted through the umbilical wound.Patients were discharged without any complications. The umbilical wounds were almost invisible 1 month after surgery. We believe that SILS, with some technical refinements, can be safely applied for distal pancreatectomy. Although the cosmetic benefits of single-incision laparoscopic distal pancreatectomy are obvious, several issues such as the extent of invasiveness, cost, indications, and learning curve need to be investigated.

A 70-year-old man with a severe COPD was scheduled for low anterior resection of the rectum because of rectal cancer. After a week of respiratory rehabilitation, respiratory function was much improved. We selected combined spinal-epidural anesthesia (CSEA) and dexmedetomidine to preserve spontaneous breathing. We obtained appropriate sedative and antianxiety effect without causing respiratory depression and hemodynamic changes. Dexmedetomidine was useful for anesthesia for a patient with severe COPD without causing respiratory depression.

A 31-year-old man with sigmoid colon cancer with concomitant simultaneous multiple liver metastases had received FOLFIRI (leucovorin, fluorouracil and irinotecan) and FOLFOX6 (leucovorin, fluorouracil and oxaliplatin) after an ordinary sigmoidectomy. However, his serum carcinoembryonic antigen (CEA) level increased rapidly during the fifteen months after the operation while he was on FOLFOX6. Abdominal computed tomography revealed expanding multiple liver tumors. As the third line chemotherapy, a combination therapy of cetuximab with irinotecan was given, which markedly reduced his levels of serum CEA, and the size and number of liver tumors. He underwent lateral segmentectomy of the liver and microwave coagulation of the liver metastases in the remnant liver. Thereafter, a good quality of life with tumor dormancy was obtained for 6 months. However, his serum CEA started to rise again in the absence of liver tumors. Therefore, FOLFOX6 with bevacizumab was chosen as the fourth line chemotherapy, and the serum CEA was reduced with tumor dormancy. A good quality of life was obtained again at 3 years after the first surgery. This report indicates the effectiveness of sandwiched liver surgery with the molecular targeting drugs cetuximab and bevacizumab on multiple liver metastases of colon cancer, and suggests the possibility of a regimen consisting of bevacizumab following cetuximab.

We report a patient who underwent laparoscopic enucleation for a nonfunctioning pancreatic neuroendocrine tumor. The patient was a 55-year-old man who had a 12- × 11-mm tumor close to the main pancreatic duct (MPD) in the pancreatic body. To avoid and detect injury to the main pancreatic duct during operation, a nasopancreatic drainage stent (NPDS) was endoscopically placed prior to the operation. According to the NPDS, the relation between the tumor and MPD was easily identified by laparoscopic ultrasonography during enucleation, thus enabling the resecting line to be determined. Moreover, after enucleation, pancreatography through the NPDS was able to clarify the absence of injury to the MPD. The NPDS was removed postoperatively, and the patient was discharged uneventfully on postoperative day 8. Preoperative placement of the NPDS seems to be a useful option for performing safe laparoscopic enucleation of pancreatic neuroendocrine tumor, especially when the lesion is located close to the MPD.

Leukemia stem cells play important roles in leukemia initiation, progression, and relapse, and represent a critical target for therapeutic intervention. BMI-1 is essential for the self-renewal of normal hematopoietic and leukemia stem cells. High expression of BMI-1 has been associated with poor prognosis in AML. PTC-209 is a novel transcriptional inhibitor of BMI-1, which has been reported to exhibit antitumor activity against cancer-initiating cells in colorectal cancer. We investigated anti-leukemia effects of the BMI-1 inhibitor PTC-209 on AML cells. A total of 8 AML cell lines (MOLM-13, OCI-AML3, MV4-11, NB4, HL-60, U-937, MOLM-14, OCI-AML2) were treated with different concentrations of PTC-209 for 48 hours and the IC50 values (concentration at which cell growth is inhibited by 50% at 48 hours of exposure) and the ED50 values (effective concentration inducing 50% killing as measured by Annexin V positivity) were determined. The IC50 values were 0.38 ± 0.07 μM (mean ± SEM), indicating high anti-proliferation effect. The ED50 values ranged from 1.2 to 2.6 μM in 7 cell lines (1.97 ± 0.22 μM) and the remaining cell line (NB4) showed relative resistance to PTC-induced apoptosis (> 10 μM). PTC-209 exhibited dose- and time-dependent anti-proliferative and cytotoxic activities, by inducing G1-S transition delay and apoptosis. PTC-209 induced conformational change of BAX (i.e., BAX activation), loss of mitochondrial membrane potential (MMP), caspase-3 activation and DNA fragmentation in addition to phosphatidylserine (PS) externalization, indicating mitochondrial apoptosis. PTC-209 induced Annexin V in primary AML cells (23.4 ± 4.6% after 48-hour treatment with 1 μM PTC-209, n = 23) in a dose-dependent manner, which is more prominent in immature CD34+CD38- population (33.7 ± 6.0%; P = 0.0036). In accordance with its high anti-leukemia activity, PTC-209 strongly reduced cellular BMI-1 levels in CD34+CD38- AML cells. Higher reduction of BMI-1 expression was positively correlated with higher susceptibility to PTC-209 in CD34+CD38- AML cells (r = 0.88; P = 0.047). The apoptotic activity was observed independent of p53 or FLT3 mutational status of the leukemia cells. Our data suggest that BMI-1 inhibition by small molecule inhibitors may be developed into a novel therapeutic strategy for AML. (Drs M. Andreeff and S. Kimura are co-senior authors with equal contribution to the work) Citation Format: Kensuke Kojima, Yuki Nishida, Aya Maeda, Dhruv Chachad, Hiroaki Kitamura, Jo Ishizawa, Michael Andreeff, Shinya Kimura. BMI-1 inhibition by PTC-209 induces mitochondrial apoptosis in acute myeloid leukemia cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2938. doi:10.1158/1538-7445.AM2015-2938

A minor fraction of leukemia cells, leukemia stem cells, have been shown to be highly resistant to current therapies and thought to be responsible for recurrence. BMI-1, a part of polycomb repressive complex 1 (PRC1) is essential for the self-renewal of normal hematopoietic and leukemia stem cells. PTC-209 is a novel selective transcriptional inhibitor of BMI-1, which has been shown to have antitumor activity against cancer-initiating cells in colorectal cancer. We investigated the prognostic significance of BMI-1 in acute myeloid leukemia (AML) using reversed phase protein array and effects of the BMI-1 inhibitor PTC-209 on primary and leukemia cell lines. BMI-1 protein expression was determined in bulk AML blasts from 511 newly diagnosed patients. BMI-1 expression was higher in unfavorable cytogenetics (n=252, median 0.068) compared to intermediate (n=225, median -0.116, P = 0.017) or favorable cytogenetics (n=34, median -0.338, P = 0.0007 versus unfavorable, 0.05 versus intermediate). Higher BMI-1 levels were associated with shorter median overall survival (42.8 versus 55.3 weeks, P = 0.046 Log Rank test). There was no correlation between BMI-1 levels and percentages of CD34 -positive cells (r = 0.07). A total of 6 AML (MOLM-13, OCI-AML3, MV4-11, NB4, HL60 and U-937) and 5 ALL (Reh, NALM6, Jurkat, Raji and MOLT-4) cell lines were exposed to PTC-209 for 48 hours. PTC-209 exhibited dose- and time-dependent anti-proliferative and cytotoxic activities. The IC50 values (concentration at which cell growth is inhibited by 50% at 48 hours of exposure) were 0.33 ± 0.04 µM (mean ± SEM) for AML and 0.55 ± 0.09 µM for ALL, indicating potent anti-proliferative effects. In contrast, PTC-209 showed differential cytotoxic effects between AML and ALL cells. The ED50 values (effective concentration inducing 50% killing as measured by Annexin V positivity) were no more than 2.5 µM in 5 of 6 AML lines while they were higher than 10 µM in 3 out of 5 ALL cell lines, implicating that BMI-1 is more critical in AML than ALL. Treatment with PTC-209 triggered several molecular events consistent with induction of apoptosis in sensitive lines (e.g. MV4-11 and MOLM-13): conformational change of BAX (i.e., BAX activation), loss of mitochondrial membrane potential (MMP), caspase-3 activation and DNA fragmentation in addition to phosphatidylserine (PS) externalization. Eighteen-hour treatment of MV4-11 cells with 2.5 µM PTC-209 led to compound-specific induction of conformationally active BAX (31%), MMP loss (80%) and caspase-3 cleavage (38%). qRT-PCR showed reduced transcript level of BMI-1 (61% reduction) after 6-hour PTC-209 exposure in MV4-11 cells. PTC-209 induced PS externalization in primary AML cells (82.5 ± 4.3% after 48-hour treatment with 2 µM PTC-209, n = 6) and to a lesser degree, in ALL cells (33.7 ± 13.4%, n = 4, p < 0.05). Importantly, CD34+CD38– AML progenitor cells were as sensitive to PTC-209 as C34– more mature AML cells. Normal lymphocytes were resistant to PTC-209 (9.1 ± 4.6% even at 10 µM). Collectively, BMI-1 inhibition by small molecule inhibitors could be developed into a novel therapeutic strategy. Disclosures No relevant conflicts of interest to declare.

Background Although adjuvant gemcitabine (GEM) chemotherapy for pancreatic cancer is standard, the quality of life (QOL) in those patients is still impaired by the standard regimen of GEM. Therefore, we studied whether mild dose-intensity adjuvant chemotherapy with bi-weekly GEM administration could provide a survival benefit with acceptable QOL to the patients with pancreatic cancer. Methods After a phase I trial, an adjuvant bi-weekly 1,000 mg/m2 of GEM chemotherapy was performed in 58 patients with pancreatic cancer for at least 12 courses (Group A). In contrast, 36 patients who declined the adjuvant bi-weekly GEM chemotherapy underwent traditional adjuvant 5FU-based chemotherapy (Group B). Careful periodical follow-ups for side effects of GEM and disease recurrence, and assessment of patients’ QOL using the EORTC QOL questionnaire (QLQ-C30) and pancreatic cancer-specific supplemental module (QLQ-PAN26) were performed. Retrospectively, the degree of side effects, patients’ QOL, compliance rate, disease-free survival (DFS), and overall survival (OS) in Group A were compared with those in Group B. Results No severe side effects (higher than Grade 2 according to the common toxicity criteria of ECOG) were observed, except for patients in Group B, who were switched to the standard GEM chemotherapy. Patients’ QOL was better in Group A than B (fatigue: 48.9 ± 32.1 versus 68.1 ± 36.3, nausea and vomiting: 26.8 ± 20.4 versus 53.7 ± 32.6, diarrhea: 21.0 ± 22.6 versus 53.9 ± 38.5, difficulty gaining weight: 49.5 ± 34.4 versus 67.7 ± 40.5, P < 0.05). Compliance rates in Groups A and B were 93% and 47%. There was a significant difference in the median DFS between both groups (Group A : B =12.5 : 6.6 months, P < 0.001). The median OS of Group A was prolonged markedly compared with Group B (20.2 versus 11.9 months, P < 0.005). For OS between both groups, univariate analysis revealed no statistical difference in 69-year-old or under females, and T1–2 factors, moreover, multivariate analysis indicated three factors, such as bi-weekly adjuvant GEM chemotherapy, T2 or less, and R0. Conclusions Adjuvant chemotherapy with bi-weekly GEM offered not only the advantage of survival benefits but the excellent compliance with acceptable QOL for postoperative pancreatic cancer patients.