High serum proteinase-3 levels predict poor progression-free survival and lower efficacy of bevacizumab in metastatic colorectal cancer

BACKGROUND

To improve the prognosis of patients with metastatic colorectal cancer (mCRC), investigating predictive biomarkers of their prognosis and chemotherapeutic responsiveness is necessary. This study aimed to analyze the clinical significance of serum proteinase-3 (PRTN3) as a predictor for prognosis and chemosensitivity, especially to bevacizumab therapy, in mCRC.

METHODS

This single-center retrospective observational study enrolled 79 patients with mCRC in our hospital and 353 patients with colorectal cancer in the TCGA database. Preoperative serum PRTN3 levels were measured using an enzyme-linked immunosorbent assay. The clinicopathological characteristics and prognosis according to serum PRTN3 levels were then evaluated. PRTN3 expression in tumor and stromal cells was evaluated immunohistochemically. The impact of PRTN3 levels on angiogenesis and bevacizumab sensitivity was evaluated using the tube formation assay.

RESULTS

Serum PRTN3 levels were an independent poor prognostic factor for progression-free survival (PFS) (hazard ratio, 2.082; 95% confidence interval, 1.118-3.647; P=0.010) in patients with mCRC. Similarly, prognostic analysis with TCGA data sets showed poorer overall survival in patients with PRTN3 expression than that in patients without PRTN3 expression, especially in patients with stage IV. Immunohistochemical analysis of resected specimens revealed that stromal neutrophils expressed PRTN3, and their expression level was significantly correlated with serum PRTN3 levels. Interestingly, the effectiveness of first-line chemotherapy was significantly poorer in the high serum PRTN3 level group. High serum PRTN3 was significantly associated with poor PFS (hazard ratio, 3.027; 95% confidence interval, 1.175-7.793; P=0.0161) in patients treated with bevacizumab, an anti-angiogenic inhibitor. The tube formation assay revealed that PRTN3 administration notably augmented angiogenesis while simultaneously attenuating the anti-angiogenic influence exerted by bevacizumab therapy.

CONCLUSIONS

Serum PRTN3 levels could be a novel predictive biomarker of PFS of first-line chemotherapy, especially for bevacizumab therapy, in patients with mCRC.

A novel prediction model of pancreatic fistula after pancreaticoduodenectomy using only preoperative markers

BACKGROUND

Since clinically relevant postoperative pancreatic fistula (CR-POPF) can cause intra-abdominal hemorrhage and abscesses, leading to surgery-related deaths after pancreaticoduodenectomy (PD), its preoperative prediction is important to develop strategies for surgical procedures and perioperative management. This study aimed to establish a novel prediction model for CR-POPF using preoperative markers.

METHODS

On a training set of 180 patients who underwent PD at the Yamaguchi University Hospital, a combination of CR-POPF predictors were explored using the leave-one-out method with a unique discrete Bayes classifier. This predictive model was confirmed using a validation set of 366 patients who underwent PD at the Osaka University Hospital.

RESULTS

In the training set, CR-POPF occurred in 60 (33%)　of 180 patients and 130 (36%)　of 366 patients in the validation set using selected markers. In patients with pancreatic ductal adenocarcinoma (PDAC), the main pancreatic duct (MPD) index showed the highest prognostic performance and could differentiate CR-POPF with 87% sensitivity and 81% specificity among 84 patients in the training set. In the validation set, the sensitivity and specificity of the MPD index-based model for 130 PDAC samples were 93% and 87%, respectively. In patients with non-PDAC, the MPD index/body mass index (BMI) combination showed the highest prognostic performance and could differentiate CR-POPF with 84% sensitivity and 57% specificity among 96 patients in the training set. In the validation set, the sensitivity and specificity of the MPD index/BMI-based model for 236 non-PDAC samples were 85% and 53%, respectively.

CONCLUSION

We developed a novel prediction model for pancreatic fistulas after PD using only preoperative markers. The MPD index and MPD index/BMI combination will be useful for CR-POPF assessment in PDAC and non-PDAC samples, respectively.

Dynamics of depressive states among university students in Japan during the COVID-19 pandemic: an interrupted time series analysis

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic was reported to have increased depression among university students which was associated with impairments in their campus lives. This study examined changes in depressive states among Japanese university students during the COVID-19 pandemic.

METHODS

A secondary data analysis from a factorial randomized controlled trial involving smartphone-based cognitive-behavioral therapy was performed. Six cohorts (N = 1626) underwent an 8-week intervention during the spring or autumn of 2019-2021, with a 9-month follow-up. We evaluated participants' depressive states weekly using the Patient Health Questionnaire-9 (PHQ-9) during the intervention, with monthly evaluations thereafter. The follow-up periods included Japan's four states of emergency (SOEs) to control COVID-19. Hypothesizing that SOEs caused a sudden worsening of depressive states, Study 1 compared the cohorts' PHQ-9 scores, and Study 2 employed time series analysis with a mixed-effects model to estimate identified changes in PHQ-9 scores.

RESULTS

Although no changes in depressive states were observed in relation to the SOEs, Study 1 identified sudden increases in PHQ-9 scores at the 28-week evaluation point, which corresponded to the beginning of the new academic year for the three autumn cohorts. In contrast, the three spring cohorts did not exhibit similar changes. Study 2 showed that, for all three autumn cohorts (n = 522), the 0.60-point change was significant (95% CI 0.42-0.78; p < .001) at 28 weeks; that is, when their timeline was interrupted.

CONCLUSIONS

While the results do not indicate any notable impact of the SOEs, they highlight the influence of the new academic year on university students' mental health during COVID-19. Trial registration UMIN, CTR-000031307. Registered on February 14, 2018.

IL-6 Levels Correlate with Prognosis and Immunosuppressive Stromal Cells in Patients with Colorectal Cancer

BACKGROUND

The prognosis for patients with colorectal cancer (CRC) is determined by tumor characteristics as well as the host immune response. This study investigated the relationship between an immunosuppressive state and patient prognosis by evaluating the systemic and tumor microenvironment (TME) interleukin (IL)-6 levels.

METHODS

Preoperative serum IL-6 levels were measured using an electrochemiluminescence assay. Expression of IL-6 in tumor and stromal cells was evaluated immunohistochemically in 209 patients with resected CRC. Single-cell analysis of tumor-infiltrating immune cells was performed using mass cytometry in 10 additional cases.

RESULTS

Elevated serum IL-6 levels were associated with elevated stromal IL-6 levels and a poor prognosis for patients with CRC. High IL-6 expression in stromal cells was associated with low-density subsets of CD3+ and CD4+ T cells as well as FOXP3+ cells. Mass cytometry analysis showed that IL-6+ cells among tumor-infiltrating immune cells were composed primarily of myeloid cells and rarely of lymphoid cells. In the high-IL-6-expression group, the percentages of myeloid-derived suppressor cells (MDSCs) and CD4+FOXP3highCD45RA- effector regulatory T cells (eTreg) were significantly higher than in the low-IL-6-expression group. Furthermore, the proportion of IL-10+ cells in MDSCs and that of IL-10+ or CTLA-4+ cells in eTregs correlated with IL-6 levels.

CONCLUSION

Elevated serum IL-6 levels were associated with stromal IL-6 levels in CRC. High IL-6 expression in tumor-infiltrating immune cells also was associated with accumulation of immunosuppressive cells in the TME.

A phase I study of a novel therapeutic vaccine as perioperative treatment for patients with surgically resectable hepatocellular carcinoma: The YCP02 trial

BACKGROUND

Developing effective adjuvant therapies is essential for improving the surgical outcomes in patients with hepatocellular carcinoma (HCC). Immunotherapy against HCC has become a promising strategy; however, only approximately 30% of all HCC patients respond to immunotherapy. Previously, we generated the novel therapeutic vaccine comprising multi-HLA-binding heat shock protein (HSP)70/glypican-3 (GPC3) peptides with a novel adjuvant combination of hLAG-3Ig and poly-ICLC. We also confirmed the safety of this vaccination therapy, as well as its capacity for the effective induction of immune responses in a previous clinical trial.

METHODS

In this phase I study, we administered this vaccine intradermally six times before surgery and ten times after surgery to patients with untreated, surgically resectable HCC (stage II to IVa). The primary endpoints of this study were the safety and feasibility of this treatment. We also analyzed the resected tumor specimens pathologically using hematoxylin and eosin staining and immunohistochemistry for HSP70, GPC3, CD8 and PD-1.

RESULTS

Twenty HLA-matched patients received this vaccination therapy with an acceptable side-effect profile. All patients underwent planned surgery without vaccination-related delay. Immunohistochemical analyses revealed that potent infiltration of CD8+ T cells into tumors with target antigen expression was observed in 12 of 20 (60%) patients.

CONCLUSIONS

This novel therapeutic vaccine was safe as perioperative immunotherapy for patients with HCC and has the potential to strongly induce CD8+ T cells infiltration into tumors. This article is protected by copyright. All rights reserved.

Clinical outcomes of second‑line chemotherapy after gemcitabine and cisplatin plus S‑1 treatment for patients with advanced biliary tract cancer in the KHBO1401‑3A study

Since the completion of the KHBO1401 study, which evaluated the efficacy of the combination of gemcitabine (GEM) and cisplatin (GC) compared with GC plus S‑1 (GCS), GCS has become a standard chemotherapy for patients with advanced biliary tract cancer (BTC). However, there are currently no data revealing second‑line therapy options after GCS. The present study aimed to evaluate the survival outcomes of patients receiving second‑line chemotherapy for advanced BTC, refractory or intolerant to GCS, using data from the KHBO1401 study. Patients who received a second‑line treatment after GCS chemotherapy between July 2014 and February 2016 were retrospectively studied. Overall survival (OS) was calculated from the day of GCS treatment failure or the first day of second‑line chemotherapy to the final follow‑up date or until death from any cause. Among 83 patients refractory or intolerant to GCS chemotherapy, 51 (61%) received second‑line chemotherapy, including GCS (n=8), GC (n=15), GEM (n=6), GEM plus S‑1 (GS) (n=4) and S‑1 (n=18). The 6‑ and 12‑month OS rates were 66.7 and 44.4%, respectively, following second‑line chemotherapy, and 6.3 and 3.1%, respectively, in the best supportive care group (P<0.0001). In addition, the 12‑ and 24‑month OS rates were 59.3 and 36.2%, respectively, in the multidrug chemotherapy group, and 26.9 and 9.0%, respectively, in the single‑agent chemotherapy group (P=0.0191). These results suggested that second‑line combination chemotherapy is a viable treatment option for patients with advanced BTC that is refractory or intolerant to first‑line GCS therapy.

Serum CCL7 Is a Novel Prognostic Biomarker of Metastatic Colorectal Cancer

BACKGROUND/AIM

Colorectal cancer is the third most common cancer globally, and the poor prognosis of patients with metastatic colorectal cancer (mCRC) warrants urgent attention. We previously obtained 10 candidate serum biomarkers for mCRC. Our aim with this study was to determine the prognostic performance of the pre-treatment serum C-C motif chemokine ligand 7 (CCL7) concentration in patients with mCRC.

PATIENTS AND METHODS

Protein concentrations of CCL7 were examined using ELISA and immunohistochemistry for serum (n=110) and surgical specimens (n=85), respectively, of patients with mCRC. The relationship between protein concentration and prognosis was examined using Cox regression analysis, receiver operator characteristic curve analysis and the Kaplan-Meier method.

RESULTS

The overall survival (OS) of patients with high concentrations of serum CCL7 was significantly poorer than that of patients with low concentrations. Patients with a high CCL7 concentration in the stroma had significantly poorer outcomes than those with a low concentration. The concentrations of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 were significantly higher in the high-CCL7 group, compared to those in the low-CCL7 group. Univariate and multivariate analysis revealed that serum CCL7 concentration was a significant prognostic factor for mCRC. The combination of serum CCL and CEA concentrations was also useful in this regard (area under the curve=0.71).

CONCLUSION

The combined pre-treatment serum levels of CCL7 and CEA are useful prognostic biomarkers for mCRC.

Effect of moderate-intensity treadmill exercise under different ambient temperatures on peripheral circulatory responses in young healthy adults

Exercise training has the potential for inducing enhancements in peripheral circulation, which can play important preventive and therapeutic roles in peripheral circulatory diseases. However, the relevant published studies show conflicting and inconclusive results. Furthermore, useful or optimum ambient temperature for this purpose has not yet been established. Therefore, we investigated the acute responses in peripheral circulation from exposure of healthy subjects to treadmill exercise under different ambient temperatures; A total of 12 young adult volunteers (males 6, females 6) randomly underwent three sessions of treadmill exercise for 30 min under three different ambient temperatures (10°C, 20°C, and 30°C), at a predetermined exercise intensity. Before and after the intervention, leg skin blood flow (SBF) was measured by laser Speckle flowgraphy and hand skin temperature (ST), by digital thermometry; After the cessation of treadmill exercise, compared to the corresponding baseline values, a significant increase in SBF was observed under all ambient temperature conditions (P<0.005). During intervention, ST showed a significant decrease at 10th min of intervention under all ambient temperatures (P<0.005) with a subsequent increasing trend in it. After intervention, a significant increase in ST was observed under 20°C condition only (P<0.05). Also, after intervention, the observed increase in systolic blood pressure was less significant under 20°C condition; Treadmill exercise appears to be a useful intervention modality in inducing improvements in peripheral circulation. However, exposure to treadmill exercise under or near 20°C ambient temperature might be recommended for the purpose.

CD4 and FOXP3 as predictive markers for the recurrence of T3/T4a stage II colorectal cancer: applying a novel discrete Bayes decision rule

Background

We recently reported the relapse-free survival (RFS) significance of the combination of CD4⁺ and forkhead box P3⁺ (FOXP3) T-cell densities identified by immunohistochemistry in patients with stage I, II, and III colorectal cancer (CRC) who underwent curative resections. This study was designed to determine the optimal combination of markers that predict recurrence in patients with T factors of T3/T4a stage II CRC by applying a novel Bayes decision rule.

Methods

Using 137 cancer tissue specimens from T3/T4a stage II patients, 12 clinicopathologic and immune factors were analysed as predictive candidates for recurrence.

Results

Our study showed that the combination of low CD4⁺ and low FOXP3⁺ T-cell densities resulted in extremely poor RFS.

Conclusions

Adjuvant chemotherapy may be considered for patients with a combination of low CD4⁺ and low FOXP3⁺ T-cell densities. The discovery of this new prognostic indicator is important for the appropriate management of patients undergoing curative resection for T3/T4a stage II CRC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-10181-7.

Risk factors for non‐gastric‐cancer‐related death after gastrectomy in elderly patients

Aim

To identify preoperative factors, especially other diseases that cause death, that are associated with the prognosis of gastrectomy in elderly patients with gastric cancer.

Methods

This retrospective study included a total of 211 consecutive patients aged ≥75 years who underwent radical gastrectomy due to gastric cancer. Time‐dependent receiver operating characteristic curve analysis was performed to determine the optimal cutoff values for various perioperative factors. Risk factors for the overall survival and death from other diseases were analyzed using the Cox proportional hazards model.

Results

Among the all perioperative factors, sex, neutrophil‐to‐lymphocyte ratio, skeletal muscle mass index, and lymph node dissection in accordance with guidelines or not extracted as independent risk factors for death from other diseases. In an analysis restricted to the preoperative factors, sex, neutrophil‐to‐lymphocyte ratio, and skeletal muscle mass index of the patients were extracted as independent risk factors for death from other diseases and overall survival. We divided the patients into four groups according to the number of preoperative risk factors for death from other diseases and found that the 5‐year non‐gastric‐cancer‐related survival was different among the four groups (risk factor 0, 91.7%; risk factor 1, 83.3%; risk factor 2, 56.3%; risk factor 3, 27.2%; P < 0.001).

Conclusion

Male sex, low skeletal muscle mass index, and high neutrophil‐to‐lymphocyte ratio are risk factors for non‐gastric‐cancer‐related death and the overall survival of elderly patients undergoing gastrectomy. Cautious treatment strategies are needed for elderly gastric cancer patients with many risk factors.

Association of Plasma Branched-Chain and Aromatic Amino Acids with Reduction in Kidney Function Evaluated in Apparently Healthy Adults

The published literature on the association of circulatory branched-chain amino acids (BCAAs) and aromatic amino acids (AAAs) with reduced kidney function is inconsistent or conflicting. Clarification of it might help to better understand the underlying pathophysiology and to determine potential biomarkers for early detection and evaluation of kidney function decline. Our main purpose was to explore and clarify the potential relationships of individual BCAAs and AAAs with estimated glomerular filtration rate (eGFR) decline. We included the data from 2804 healthy subjects and categorized them into three groups based on eGFR tertiles. The associations between individual amino acids and eGFR were explored by covariate-adjusted logistic regression models. There was a progressive increase in the concentrations of BCAAs and AAAs from the upper to the lower tertiles. We revealed significant positive associations of isoleucine, leucine, and phenylalanine with lower tertiles of eGFR in the adjusted models (p < 0.01-0.001). The findings hold a promising potential of using plasma isoleucine, leucine, and phenylalanine levels for evaluation of kidney function decline. Future longitudinal studies should investigate the causal association between altered levels of these amino acids and impaired kidney function and also the utility of the former as potential biomarkers for evaluating the risk and early detection of the latter.

Precision length determination and in silico simulation in PCR of microsatellite repeat sequences

Despite being commonplace, polymerase chain reactions (PCRs) still contain many unknown aspects. One example is microsatellite PCR, which is now widely used for various purposes from ecology to cancer medicine. Since this category of repetitive DNA sequences induces polymerase slippage not only in vivo but also in vitro, microsatellite PCR products comprise a complex combination of DNA fragments with various lengths and have, therefore, been empirically interpreted. The primary obstacle for understanding microsatellite PCR was the intrinsic inaccuracy in sizing of DNA fragments in capillary electrophoresis (CE), which, however, has been overcome by elucidating intrinsic sizing errors in each fragment length range. Secondly, the slippage properties of the thermostable polymerases were first clarified in detail using primer extension assays. Furthermore, using the obtained slippage parameters and our original program, we have first reconstructed microsatellite PCR in silico. The entire processes of complex microsatellite PCR have, thus, been more clearly understood.

Laparoscopic resection reduces superficial surgical site infection in liver surgery

BACKGROUND

Laparoscopic liver resection is beneficial compared to open liver resection. This study aimed to evaluate whether laparoscopic liver resection could reduce postoperative infections.

METHODS

This study included 125 and 115 patients with liver tumors who underwent open and pure laparoscopic partial resections or left lateral sectionectomies, respectively. Propensity score matching and stabilized inverse probability of treatment weighting were carried out to compare the postoperative infectious complication rates between the two groups.

RESULTS

Patients with tumors located in Couinaud segment 1, 7, or 8; with tumors adjacent to major vessels; or who underwent repeated resections were more likely to receive open resection. After propensity score matching, the superficial incisional surgical site infection rate tended to be lower in the laparoscopic liver resection group than in the open liver resection group. Moreover, overall infectious complication rate and superficial incisional surgical site infection rate were lower in the laparoscopic group (the cohort formed by the stabilized inverse probability of treatment weighting).

CONCLUSIONS

Using the laparoscopic approach for partial resections and left lateral sectionectomies for liver tumors, the superficial incisional surgical site infection rate could be reduced.

Siglec-7 is a predictive biomarker for the efficacy of cancer vaccination against metastatic colorectal cancer

Cancer immunotherapy, including vaccination, is considered a major scientific and medical breakthrough. However, cancer immunotherapy does not result in durable objective responses against colorectal cancer (CRC). To improve the efficacy of immunotherapy, the present study investigated several biomarkers for selecting patients who were expected to respond well to immunotherapy. Firstly, a comprehensive proteomic analysis was performed using tumor tissue lysates from patients enrolled in a phase II study, in which five human leukocyte antigen (HLA)-A*24:02-restricted peptides were administered. Sialic acid-binding immunoglobulin type lectin (Siglec)-7 was identified as a potential predictive biomarker. Subsequently, this biomarker was validated using western blot analysis, and immunofluorescence using tissue samples from the patients enrolled in the phase II study. The expression levels of Siglec-7 detected by immunofluorescence were quantified and their association with overall survival (OS) in patients treated with the peptide vaccine was examined. Furthermore, considering the important role of tumor-infiltrating lymphocytes (TILs) for CRC prognosis, the densities of CD3⁺, CD4^+, CD8⁺ and forkhead box P3 (FOXP3)⁺ T cells in CRC tissues were examined and compared with Siglec-7 expression. The mean expression levels of Siglec-7 were significantly higher in patients with poor prognosis, with an OS of ≤2 years, as shown in comprehensive proteomic analysis (P=0.016) and western blot analysis (P=0.025). Immunofluorescence analysis demonstrated that Siglec-7 was expressed in intratumoral macrophages. The OS in patients with high Siglec-7 expression was significantly shorter than in that in patients with low Siglec-7 expression (P=0.017) in the HLA-A*24:02-matched patients. However, this difference was not observed in the HLA-unmatched patients. There was no significant difference in OS between patients according to the numbers of TILs, nor significant correlation between TILs and Siglec-7 expression. In conclusion, Siglec-7 expression in macrophages in tumor tissue may be a novel predictive biomarker for the efficacy of immunotherapy against metastatic CRC.

Viral elimination is essential for improving surgical outcomes of hepatitis C virus-related hepatocellular carcinoma: Multicenter retrospective analysis

AIM

The impact of sustained virologic response (SVR) on surgical outcomes for patients with hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) remains controversial. This study aimed to evaluate the influence of SVR on long-term surgical outcomes after hepatectomy.

METHODS

This multicenter study included 504 patients who underwent curative resection for HCV-related HCC. Patients with a history of HCC treatment, HBV infection, poor liver function, and tumor with major vascular invasion were excluded. Long-term surgical outcomes (overall survival [OS] and recurrence-free survival [RFS]) among patients who achieved SVR before hepatectomy (Pre-SVR group: 58 patients), after hepatectomy (Post-SVR group: 54 patients), and without SVR (Non-SVR group: 186 patients) were compared after adjusting for 13 confounding factors. Using the surgically resected specimens, comparison of the pathological changes in liver fibrosis between the first and second hepatectomy were analyzed.

RESULTS

Patients with SVR were younger, had better liver function, and less liver fibrosis compared to patients without SVR. Propensity score-matched OS and RFS were significantly better in Pre-SVR group than Non-SVR group (P = .029 and P = .009, respectively). Inverse probability-weighted OS and RFS were also significantly better in the Post-SVR group (P = .001 and P = .021, respectively) than in the Non-SVR group. Histopathological evaluation revealed that only the patients with SVR had regression of liver fibrosis (P < .05).

CONCLUSION

Achievement of SVR before or after hepatectomy is essential for improving long-term surgical outcomes in patients with HCV-related HCC.

Determining the protective characteristics and risk factors for the development of anastomotic leakage after low anterior resection for rectal cancer

Purpose

Anastomotic leakage is one of the most serious postoperative complications associated with surgery for rectal cancer. The present study aimed to identify the protective characteristics and risk factors associated with anastomotic leakage after low anterior resection for rectal cancer.

Methods

This was a retrospective, single-center study conducted between January 2009 and December 2017 at our institution. In total, 136 rectal cancer patients who underwent low anterior resection were included in the study. We analyzed preoperative and intraoperative factors. In addition, the pelvic dimensions were measured using computed tomography in all cases.

Results

Among the 136 patients, anastomotic leakage occurred in 21 (15.4%), including 18 males and 3 females. The median body mass index was 21.1 kg/m². The construction of a covering stoma was found to be a protective factor. In addition, the operation time (≥ 373 min), intraoperative blood loss (≥ 105 ml), and size of the pelvic inlet (≥ 113 mm) were identified as risk factors for anastomotic leakage.

Conclusion

The construction of a covering stoma was a possible protective factor. However, a longer operation time, higher intraoperative blood loss, and larger pelvic inlet dimensions were possible risk factors for developing anastomotic leakage after low anterior resection in patients with rectal cancer.

Abstract CT251: Immunological and histopathological tumor responses to a novel neoadjuvant peptide vaccine targeting HSP70 and GPC3 antigens in patients with resectable HCC

Background: Even with curative resection, the recurrence rate of HCC remains high, and effective adjuvant therapies are not currently available. Our previous Phase I study with novel therapeutic peptides and immune adjuvants demonstrated safety, antigen-specific CTL induction in PBMC, and a sign of efficacy (ASCO 2017 Abstract # 3086). We thus started a Phase I study of the same vaccination therapy as a perioperative immunotherapy setting in patients with resectable HCC (jRCTs061180058). Methods: Two mg each of HLA-A*24:02, 02:01, or 02:06-restricted HSP70- and GPC3-derived peptides, in combination with hLAG-3Ig (1.0 mg) + poly-IC:LC (1.4 mg) were injected intradermally at four sites of the inguinal and axillary regions every week for 6 weeks before surgery. Patients subsequently received 10 injections of adjuvant immunotherapy over 4 months. Surgical specimens and PBMCs were analyzed by mass cytometry (CyTOF), using 66 antibodies to monitor T-cell exhaustion, T-cell activation, and effector Treg induction. Tumor specimens were also subjected to HE staining and immunohistochemical staining for CD3, CD8, PD1, HSP70, and GPC3. Results: Nine patients were treated with preoperative vaccination, and resected surgical specimens and PBMC were examined. Pathohistological analysis revealed three response types: “hot cellular immunity”, “intermediate fumoral immunity”, and “cold response”. In three patients, massive infiltration of CD8+ and PD1+ T cells accompanied necrotic and fibrous regions, in which the targeted tumor antigens HSP70 and GPC3 were highly expressed, representing “hot cellular immunity”. Regarding “intermediate”, three patients showed necrotic regions with infiltrating macrophages. HSP70 and/or GPC3 were also highly expressed, but little infiltration of lymphocytes was evident. In the remaining three patients, “cold response” manifested as tumor comprising a pseudo-glandular pattern with no infiltration of T cells or macrophages. Two of these three patients showed no expression of targeted tumor antigens. CyTOF analysis of the tumors also revealed the percentages of CD3+ cells among live cells and of PD1+ cells among CD8+ cells were extremely low in cold response. However, this trend was not observed in PBMCs, suggesting the critical importance of TIL analysis. Conclusions: This novel therapeutic peptide and immune adjuvant combination induced sustained immune cell infiltration into tumor microenvironments, especially in those presenting target tumor-associated antigens with a non-pseudo-glandular type. Our novel immunotherapy may convert cold tumors into hot tumors containing PD1+ lymphocytes. Combining this novel strategy with PD (L) 1 antibody may be warranted.

Citation Format: Masao Nakajima, Shoichi Hazama, Koji Tamada, Keiko Udaka, Shun Doi, Michiie Sakamoto, Akira Saito, Shiro Akinaga, Hiroto Matsui, Yoshitaro Shindo, Satoshi Matsukuma, Yukio Tokumitsu, Shinobu Tomochika, Michihisa Iida, Shin Yoshida, Ryouichi Tsunedomi, Yuki Nakagami, Nobuaki Suzuki, Shigeru Takeda, Hiroaki Nagano. Immunological and histopathological tumor responses to a novel neoadjuvant peptide vaccine targeting HSP70 and GPC3 antigens in patients with resectable HCC [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr CT251.

The effect of the visceral fat area on the predictive accuracy of C-reactive protein for infectious complications after laparoscopy-assisted gastrectomy

AIM

To investigate the influence of visceral fat area on postoperative C-reactive protein levels and whether it affects its ability to diagnose infectious complications after laparoscopy-assisted gastrectomy.

METHODS

A total of 435 consecutive patients who underwent laparoscopy-assisted resection for gastric cancer from 2008 to 2017 were reviewed and divided into four groups according to visceral fat area quartiles. We evaluated the relationship between C-reactive protein and visceral fat area and whether visceral fat area affects the sensitivity and specificity of C-reactive protein in diagnosing postoperative infectious complications.

RESULTS

Postoperative C-reactive protein levels increased with increasing visceral fat areas at every postoperative assessment. Multiple linear regression revealed that levels on postoperative day 3 significantly positively correlated with visceral fat area. Postoperative day 3 levels also showed moderate accuracy for diagnosing infectious complications (area under the curve, 0.78; sensitivity, 0.86; specificity, 0.65), with an optimal cut-off of 11.8 mg/dL. The sensitivity for predicting infectious complications was low in the 1st visceral fat area quartile group but high in the 2nd, 3rd, and 4th groups (0.43 vs 1.0 vs 1.0 vs 0.94, respectively). By contrast, the specificity was high in the 1st and 2nd group but low in the 3rd and 4th (0.84 vs 0.70 vs 0.54 vs 0.48, respectively).

CONCLUSION

Visceral fat area positively correlated with postoperative C-reactive protein levels and this affected its accuracy in diagnosing infectious complications. A uniform C-reactive protein cut-off may not provide accurate predictions in patients with more extreme visceral fat areas.

Serum LOX-1 is a novel prognostic biomarker of colorectal cancer

BACKGROUND

Colorectal cancer is the third most common cancer worldwide. If biomarkers can be identified in liquid biopsy, diagnosis and treatment can be optimized even when cancerous tissues are not available. The purpose of this study was to identify proteins from liquid biopsy that would be useful as markers of poor prognosis.

METHODS

First, we comprehensively analyzed serum proteins to identify potential biomarkers and focused on serum lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1). The relationship between LOX-1 and the prognosis of patients with colorectal cancer has not been reported. Next, we validated this marker using serum samples from 238 patients with colorectal cancer by ELISA and 100 tissue samples by immunohistochemical staining.

RESULTS

The optimal cut-off value of serum LOX-1 was 538.7 pg/mL according to time-dependent receiver operating characteristics curve analysis. The overall survival of patients with high levels of serum LOX-1 was significantly poorer than that of individuals with low levels of LOX-1 in the training and test datasets. In multivariate analysis for overall survival, serum LOX-1 was an independent prognostic factor identified in liquid biopsy (hazard ratio = 1.729, p = 0.027). The prognosis of patients with high LOX-1 expression in tumor tissues was significantly poorer than that of individuals with low expression (p =0.047 ). Additionally, inflammatory factors such as white blood cell count, C-reactive protein level, neutrophil/lymphocyte ratio, and monocyte/lymphocyte ratio were significantly higher in the group with high serum LOX-1 levels.

CONCLUSIONS

Serum LOX-1 might be a useful biomarker of poor prognosis in colorectal cancer.

A phase I study of multi-HLA-binding peptides derived from heat shock protein 70/glypican-3 and a novel combination adjuvant of hLAG-3Ig and Poly-ICLC for patients with metastatic gastrointestinal cancers: YNP01 trial

Background

This phase I study aimed to evaluate the safety, peptide-specific immune responses, and anti-tumor effects of a novel vaccination therapy comprising multi-HLA-binding heat shock protein (HSP) 70/glypican-3 (GPC3) peptides and a novel adjuvant combination of hLAG-3Ig and Poly-ICLC against metastatic gastrointestinal cancers.

Methods

HSP70/GPC3 peptides with high binding affinities for three HLA types (A*24:02, A*02:01, and A*02:06) were identified with our peptide prediction system. The peptides were intradermally administered with combined adjuvants on a weekly basis. This study was a phase I dose escalation clinical trial, which was carried out in a three patients’ cohort; in total, 11 patients were enrolled for the recommended dose.

Results

Seventeen patients received this vaccination therapy without dose-limiting toxicity. All treatment-related adverse events were of grades 1 to 2. Peptide-specific CTL induction by HSP70 and GPC3 proteins was observed in 11 (64.7%) and 13 (76.5%) cases, respectively, regardless of the HLA type. Serum tumor marker levels were decreased in 10 cases (58.8%). Immunological analysis using PBMCs indicated that patients receiving dose level 3 presented with significantly reduced T cell immunoglobulin and mucin-domain containing-3 (TIM3)-expressing CD4 + T cells after one course of treatment. PD-1 or TIM3-expressing CD4 + T cells and T cell immunoreceptor with immunoglobulin and ITIM domains (TIGIT)-expressing CD8 + T cells in PBMCs before vaccination were negative predictive factors for survival.

Conclusions

This novel peptide vaccination therapy was safe for patients with metastatic gastrointestinal cancers.

Electronic supplementary material

The online version of this article (10.1007/s00262-020-02518-7) contains supplementary material, which is available to authorized users.

Association between polymorphisms in EGFR and tumor response during cetuximab and oxaliplatin-based combination therapy in metastatic colorectal cancer: Analysis of data from two clinical trials

Predicting tumor response prior to starting anti-epidermal growth factor receptor (EGFR) antibody therapy would benefit patients with advanced/metastatic colorectal cancer (mCRC). The present study investigated the association between efficacy of cetuximab treatment and gene polymorphisms of fragment C γ receptor (FcγR) 2A, FcγR3A and EGFR in patients with extended RAS/BRAF wild-type mCRC. Clinical data and specimens were obtained from 90 patients who participated in either of two clinical studies evaluating the first-line, cetuximab plus oxaliplatin-based treatment. It was hypothesized that polymorphisms H/H of FcγR2A, V/V of FcγR3A, K/K of EGFR and <36 CA repeats in the EGFR gene may be associated with a favorable tumor response. Multivariate analysis demonstrated that patients with the H/H polymorphism tended to have an improved tumor response compared with the non-H/H population, although the result was not significant [odds ratio, 2.25; 95% confidence interval (CI), 0.89–5.66; P=0.09]. Univariate analysis revealed increased tumor shrinkage in patients with the K/K polymorphism of EGFR compared with the other polymorphisms (mean ± standard deviation, −55.3±28.4 vs. −39.6±40.8%; P=0.04). Subsequent multivariate analysis confirmed that the K/K polymorphism of EGFR predicted greater tumor shrinkage (multiple linear regression analysis estimate, −19.3; 95% CI, −35.5 to 3.0; P=0.02), with the tendency toward a preferable response in patients with <36 CA EGFR gene repeats (estimate, −16.9; 95% CI; −34.4 to 0.6; P=0.06). However, other polymorphisms and clinical variables did not predict tumor shrinkage. In conclusion, the present study demonstrated that polymorphisms of EGFR, FcγR2A and FcγR3A may differentiate the patients that obtain the maximum benefit from cetuximab treatment.

Intratumoural-infiltrating CD4 + and FOXP3 + T cells as strong positive predictive markers for the prognosis of resectable colorectal cancer

Background

CD3 +  and CD8 + T-cell infiltration were reported as positive predictive markers of survival in colorectal cancer (CRC) patients. Here, we demonstrate the prognostic significance of CD4 + and FOXP3 + T-cell densities in CRC.

Methods

We quantified the intratumoural densities of CD3 + , CD8 + , CD4 +  and FOXP3 + T cells by immunohistochemistry and digital pathology in 342 CRC patients who underwent curative resection. Microsatellite instability was also assessed in 322 specimens. Patient demographics, clinicopathological features and survival rates were analysed.

Results

High CD3 + , CD4 +  and FOXP3 + T-cell densities were associated with improved relapse-free survival (RFS); high CD8 + , CD4 +  and FOXP3 + T-cell densities were associated with improved disease-specific survival (DSS). Patients with low CD4 + and low FOXP3 + T-cell densities exhibited extremely poor prognoses. T stage, vascular/lymphatic invasion and CD4 + T-cell density were independent prognostic indicators for DSS. The distributions of CD4 + and FOXP3 + T-cell densities were not significantly different between the high microsatellite instability group and other groups, in contrast to those of CD3 + and CD8 + T-cell densities.

Conclusions

Intratumoural CD4 + T-cell density and combined CD4 + and FOXP3 + T-cell densities were stronger prognostic indicators than other clinicopathological features. These results may facilitate the establishment of novel prognostic factors and therapeutic strategies for CRC.

Induction of antigen specific CD8+ T cell infiltration by a novel neoadjuvant vaccine containing HSP70 and GPC3 peptides plus soluble LAG-3 and Poly-IC:LC: Interim results of a Phase I study

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Background: Even with curative resection, the recurrence rate of HCC is still high, and no effective adjuvant therapy is currently available. Our previous Phase I study with novel therapeutic peptides and immune adjuvants demonstrated the safety, antigen specific CTL induction in PBMC and a sign of efficacy (ASCO 2017 Abstract # 3086); thus, we started Phase I study of the same therapy as a perioperative immunotherapy setting in patients with resectable HCC (UMIN000029991). Methods: Two mg each of HLA-A*24:02, 02:01, or 02:06 restricted HSP70- and GPC3-derived peptides, in combination with hLAG-3Ig (1.0 mg) + Poly-IC:LC (1.4 mg) were injected intradermally at four sites of the inguinal and axillary regions every week for 6 weeks before surgery. Patients subsequently received 10 injections of adjuvant immunotherapy over 4 months. Surgical specimens and PBMCs were analyzed by mass cytometry (CyTOF), using 66 antibodies to monitor T cell exhaustion, T cell activation, Effector Treg induction, etc. Tumor specimens were also subjected to immunohistochemical staining of CD3, CD8, PD1, HSP70, and GPC3. The reason for early reporting is the interesting findings at the foci of HCC, and the interim analyses was approved by the Data and Safety Monitoring Committee. Results: Of the 11 screened patients, 5 completed the treatments and were analyzed. We found massive CD8+ T lymphocyte infiltration in the intratumor foci of HCC, which is usually accompanied by peritumoral lymphocytic infiltration. Moreover, the density of lymphocytes was markedly higher in areas of HSP70 or GPC3 antigen expression. One case out of five recurred 5 month after surgery and it showed low CD8+ and PD1+ cell infiltration and high effector Treg (CD4+/CD25+/CD45RA-/FoxP3 +) infiltration. This trend was not observed in PBMC, suggesting the importance of TIL analysis. The high PD1 expression was accompanied by massive intratumoral infiltration of CD8+ lymphocytes. Conclusions: The novel therapeutic peptide and immune adjuvant combination induced sustained immune cell infiltration into tumor microenvironments, especially those presenting target tumor-associated antigens. Our novel immunotherapy may convert cold tumors into hot tumors containing PD1+ lymphocytes. Thus, the combination of this novel strategy with PD (L) 1 antibody is warranted. Clinical trial information: 000029991.

Analysis of UGT1A’s polymorphisms and RAS: RAF mutations based on phase II study of biweekly XELIRI plus bevacizumab as a second-line therapy in patients with metastatic colorectal cancer

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Background: We have previously reported biweekly XELIRI + bevacizumab 10 mg/kg as second-line chemotherapy in metastatic colorectal cancer (mCRC). In this study, we investigated relationships between efficacy/toxicity and biomarkers (polymorphisms of UGT1A’s, somatic mutations of RAS, BRAF and PIK3CA). Methods: Patients with mCRC who had received prior chemotherapy including oxaliplatin based regimen were eligible for this study. Treatment protocol administrated capecitabine 1,000 mg/m2 twice daily from the evening of day 1 to the morning of day 8, intravenous irinotecan 150mg/m2 on day 1, and bevacizumab 10 mg/kg on day 1 every 2 weeks. Results: Between January 2013 and July 2015, 51 patients were enrolled in this study. The patients’ characteristics were as follows (N=51): median age, 66 years (range 41–82); male/female, 29/22; the median PFS was 5.47 months (95% CI, 4.23–7.40 months), the median OS was 13.5months (95%CI, 11.57– 20.23months), and the median TTF was 4.5 months (95%CI, 3.97–6.93 months). The response rate was 16% (95%CI, 7.2–29.1), and the disease control rate was 76% (95%CI, 61.8-86.9). Grade 3 or higher adverse events were mainly febrile neutropenia in two patients and hypertension in 14 patients (28.6%). The patients with UGT1A7 (387G<T) genotype had a trend to suffer from diarrhea ( p=0.089 by Fisher’s exact test). The summary of somatic mutations of cancer was RAS (wild/mutant = 21/23), BRAF (wild/mutant = 39/5), PIK3CA (wild/mutant = 42/0), and MSI (MSS/MSI-H = 42/2). There was no statistical association between efficacy and somatic mutations. The sample size might influenced such the results. Conclusions: In mCRC patients, biweekly XELIRI + bevacizumab 10 mg/kg is effective and feasible as second-line chemotherapy. We found several biomarkers that predict toxicities in this study. Further study is required for predicting the efficacy based on biomarkers using somatic mutations of cancer and germline polymorphisms. Clinical trial information: UMIN000009280.

Monocular inhibition reveals temporal and spatial changes in gene expression in the primary visual cortex of marmoset

We investigated the time course of the expression of several activity-dependent genes evoked by visual inputs in the primary visual cortex (V1) in adult marmosets. In order to examine the rapid time course of activity-dependent gene expression, marmosets were first monocularly inactivated by tetrodotoxin (TTX), kept in darkness for two days, and then exposed to various length of light stimulation. Activity-dependent genes including HTR1B, HTR2A, whose activity-dependency were previously reported by us, and well-known immediate early genes (IEGs), c-FOS, ZIF268, and ARC, were examined by in situ hybridization. Using this system, first, we demonstrated the ocular dominance type of gene expression pattern in V1 under this condition. IEGs were expressed in columnar patterns throughout layers II–VI of all the tested monocular marmosets. Second, we showed the regulation of HTR1B and HTR2A expressions by retinal spontaneous activity, because HTR1B and HTR2A mRNA expressions sustained a certain level regardless of visual stimulation and were inhibited by a blockade of the retinal activity with TTX. Third, IEGs dynamically changed its laminar distribution from half an hour to several hours upon a stimulus onset with the unique time course for each gene. The expression patterns of these genes were different in neurons of each layer as well. These results suggest that the regulation of each neuron in the primary visual cortex of marmosets is subjected to different regulation upon the change of activities from retina. It should be related to a highly differentiated laminar structure of marmoset visual systems, reflecting the functions of the activity-dependent gene expression in marmoset V1.

Visualization of cortical projection neurons with retrograde TET-off lentiviral vector

We are interested in identifying and characterizing various projection neurons that constitute the neocortical circuit. For this purpose, we developed a novel lentiviral vector that carries the tetracycline transactivator (tTA) and the transgene under the TET Responsive Element promoter (TRE) on a single backbone. By pseudotyping such a vector with modified rabies G-protein, we were able to express palmitoylated-GFP (palGFP) or turboFP635 (RFP) in corticothalamic, corticocortical, and corticopontine neurons of mice. The high-level expression of the transgene achieved by the TET-Off system enabled us to observe characteristic elaboration of neuronal processes for each cell type. At higher magnification, we were able to observe fine structures such as boutons and spines as well. We also injected our retrograde TET-Off vector to the marmoset cortex and proved that it can be used to label the long-distance cortical connectivity of millimeter scale. In conclusion, our novel retrograde tracer provides an attractive option to investigate the morphologies of identified cortical projection neurons of various species.

Identification of cis-acting regions that contribute to neuron-specific expression of the GAP-43 gene

There are two transcription start sites in the growth-associated protein 43 (GAP-43) promoter, and several repressive elements have been reported in the control region. But the repressive effects have been analyzed only for the distal transcription start site. Among the repressive elements reported, we found that modulator I repressed GAP-43 gene expression from the proximal promoter in non-neuronal cells. We also found a novel stimulative element immediately downstream of modulator I.

Observation of magnetic multilayers by electron holography

Magnetic structures of Co/Cu multilayers in cross section are observed by two kinds of electron holography: a Fourier method and a phase-shifting method, which is introduced briefly. The Fourier method can easily reconstruct wave functions and is applied to many specimens, whereas the phase-shifting method requires longer time for processing, but has a higher spatial resolution that permits us to discuss fine structures. Magnetization vectors in Co layers aligning parallel and separating into two blocks with antiparallel alignment are observed. Magnetic blurring on the boundary between Co and Cu in the reconstructed phase images is larger than the estimated atomic roughness.

Correlation between major histocompatibility complex class I molecules and CD8+ T lymphocytes in prostate, and quantification of CD8 and interferon-gamma mRNA in prostate tissue specimens

OBJECTIVE

To investigate the immunology of host-tumour interaction, critical for the development of immunotherapy against cancers, by assessing the major histocompatibility complex (MHC) class I expression in both benign and malignant prostate disease, and the relationship between their expression and degree of tumour-infiltrating lymphocytes.

MATERIALS AND METHODS

Direct serial analysis of gene expression in tumours is an extremely sensitive and powerful tool for monitoring immunological changes in the immunotherapy of solid tumours. Most previous monitoring protocols rely mainly on the analysis of patient's peripheral blood but in the present study the direct molecular analysis of small tissue samples was used, and its accuracy compared with that of conventional immunohistochemical analysis. Twenty-four formalin-fixed, paraffin-embedded prostate samples (11 benign and 13 carcinoma) were used for the immunohistochemical analysis of CD8+ T lymphocytes and MHC class I expression. CD8+ T lymphocytes were counted using an ocular grid and MHC class I measured using digital image-analysis software. Twenty-seven frozen prostate tissue samples (12 benign and 15 carcinoma) were used for direct gene measurements of CD8 and interferon-gamma using a quantitative real-time polymerase chain reaction.

RESULTS

There were significantly fewer CD8+ T lymphocytes in prostate carcinoma nests than in benign prostate. There was a significant correlation between the number of CD8+ T lymphocytes and MHC class I expression in the prostate. There was a strong correlation between the immunohistochemical estimates of CD8+ T lymphocytes and CD8 gene by polymerase chain reaction, but no significant difference between benign prostate and prostate carcinoma tissue in gene measurements.

CONCLUSION

Down-regulation of MHC class I expression by prostate cancer cells is associated with fewer CD8+ T lymphocytes and hence might be important in cancer growth. In addition, the measurement of gene expression in small tissue samples might be useful for monitoring the efficacy of treatment throughout cancer therapy.

Heat shock protein 70 (HSP70) does not prevent the inhibition of cell growth in DU-145 cells treated with TGF-beta1

BACKGROUND

Mitogen-activated protein kinase (MAPK) is one of the transforming growth factor-beta (TGF-beta signaling pathways while heat shock protein 70 (HSP70) prevents apoptosis by affecting MAPK signaling downstream. However, the interrelationship between TGF-beta and HSP70 signaling is still unknown.

MATERIALS AND METHODS

DU-145 prostate cancer cells were treated with 40 pM and 200 pM TGF-beta1. After 3, 6, 9, 12 and 24 hours, cell proliferation assay and cell cycle analysis were performed. The activities of HSP70 and MAPKs (c-Jun N-terminal kinase 1 (JNK1), extracellular signal-regulated kinase 1 (ERK1), ERK2 and p38) were analyzed by Western blot at each time-point.

RESULTS

TGF-beta1 inhibited the cell growth in a dose-dependent manner at 3 hours. Late G1 accumulation in the cell cycle was observed in a dose-dependent manner after 24 hours. HSP70 and JNK1 increased only at 3 hours and decreased for up to 24 hours thereafter. ERK1, ERK2 and p38 decreased from 3 to 24 hours after TGF-beta1 treatment.

CONCLUSION

These data suggest that HSP70 does not prevent the inhibition of cell growth in DU-145 cells treated with TGF-beta1.

An occurrence of salmonella infection in cranes at the Izumi Plains, Japan

Ten thousand or more cranes migrate from Siberia and stay at the Izumi Plains, in the northern part of Kagoshima prefecture, Japan, every winter season. Four hundred and twenty samples of cranes feces were obtained 1995 to 1997 and investigated for Salmonella. As a result, twenty-nine of Salmonella strains were isolated. All isolates were determined to be identical, Salmonella Typhimurium (04:i: 1,2). since all of them indicated the same patterns of plasmid profiling and antibiotic sensitive spectrums. The isolates showed a high pathogenicity to chicken, and most of them were isolated in the latter half of the winter season; therefore the cranes were infected with the isolates during the winter season.

Endogenous meltrin alpha is ubiquitously expressed and associated with the plasma membrane but exogenous meltrin alpha is retained in the endoplasmic reticulum

Meltrin alpha (ADAM12) is a member of the ADAM (MDC) protein family characterized by the presence of metalloprotease and disintegrin domains. ADAM proteins contain single transmembrane domains, and the processed mature proteins are postulated to span the plasma membrane. It has been reported that transfection of a truncated meltrin alpha cDNA lacking the prodomain and metalloprotease domain promotes skeletal muscle cell fusion. We show here that meltrin alpha was constitutively expressed in both undifferentiated and differentiated C2 skeletal muscle cells and also in fibroblasts. Both its precursor and processed mature forms were present in these cells. Thus, meltrin alpha may play general roles in addition to its roles in myogenesis. Since endogenous meltrin alpha cannot be detected by immunofluorescence microscopy, we examined the location of the exogenously expressed protein by transfection. Unexpectedly, the exogenously expressed meltrin alpha was located to a network structure of the endoplasmic reticulum (ER) but not to the plasma membrane. Cell fractionation revealed that the intrinsic mature protein was associated with the plasma membrane. However, the exogenously expressed protein remained unprocessed. These results seem to imply that the exogenously expressed meltrin alpha is not translocated from the ER to the trans-Golgi network, where a processing enzyme resides, and that it is consequently not converted to the mature form. Thus, the transfected meltrin alpha is unlikely to exert its physiological functions. Conversely, the ER may serve as a reservoir of the latent form of intrinsic meltrin alpha.

Meltrin alpha cytoplasmic domain interacts with SH3 domains of Src and Grb2 and is phosphorylated by v-Src

Meltrin alpha/ADAM12 is a member of the ADAM/MDC family proteins characterized by the presence of metalloprotease and disintegrin domains. This protein also contains a single transmembrane domain and a relatively long cytoplasmic domain containing several proline-rich sequences. These sequences are compatible with the consensus sequences for binding the Src homology 3 (SH3) domains. To determine whether the proline-rich sequences interact with SH3 domains in several proteins, binding of recombinant SH3 domains to the meltrin alpha cytoplasmic domain was analysed by pull-down assays. The SH3 domains of Src and Yes bound strongly, but that of Abl or phosphatidylinositol 3-kinase p85 subunit did not. Full-length Grb2/Ash bound strongly, whereas its N-terminal SH3 domain alone did less strongly. Src and Grb2 in bovine brain extracts also bound to meltrin alpha cytoplasmic domain on affinity resin. Furthermore, immunoprecipitation with a monoclonal antibody to meltrin alpha resulted in coprecipitation of Src and Grb2 with meltrin alpha in cell extracts, suggesting that Src and Grb2 are associated in vivo with meltrin alpha cytoplasmic domain. This notion was also supported by the findings that exogenously expressed meltrin cytoplasmic domain coexisted with Src and Grb2 on the membrane ruffles. The C-terminal Tyr901 of meltrin alpha was phosphorylated both in vitro and in cultured cells by v-Src. These results may imply that meltrin alpha cytoplasmic domain is involved in a signal transduction for some biological function through the interaction with SH3-containing proteins.

Kynurenine concentration of serum was increased by exercise

Kynurenine pathway of tryptophan makes a lot of physiological active substances, such as quinolinate, NAD and so on, suggesting that kynurenine itself may play a very important role physiologically. Therefore, we examined the influence of exercise on serum kynurenine concentration. At first, we assayed kynurenine concentration of students (n = 13) who took part in a rugby camp for three days. The mean value of kynurenine concentration of before and after training were 1.362 +/- 0.306 microM and 1.725 +/- 0.511 microM respectively. These data means that severe exercise rise the serum kynurenine concentration. Then we tried to examine the relationship between the level of exercise and serum kynurenine concentration. Serum kynurenine concentration had significantly increased immediately after the exercise from 1.869 +/- 0.285 microM to 2.138 +/- 0.248 microM of 24 hours later by loading of 65% heart rate max exercise for each subject. These results suggested that at least the severe exercise affect on the tryptophan metabolism. We will discuss the change of serum kynurenine concentration by another sports such as soccer game and 20 km run.

Laminin degradation by plasmin regulates long-term potentiation

Plasmin is converted from its zymogen plasminogen by tissue type or urokinase type plasminogen activator (PA) and degrades many components of the extracellular matrix (ECM). To explore the possibility that the PA-plasmin system regulates synaptic plasticity, we investigated the effect of plasmin on degradation of ECM and synaptic plasticity by using organotypic hippocampal cultures. High-frequency stimulation produced long-term potentiation (LTP) in control slices, whereas the potentiation was induced but not maintained in slices pretreated with 100 nM plasmin for 6 hr. The baseline synaptic responses were not affected by pretreatment with plasmin. The impairment of LTP maintenance was not observed in slices pretreated with 100 nM plasmin for 6 hr, washed, and then cultured for 24-48 hr in the absence of plasmin. To identify substrates of plasmin, the expression of three major components of ECM, laminin, fibronectin, and type IV collagen, was investigated by immunofluorescence imaging. The three ECM components were widely distributed in the hippocampus, and only laminin was degraded by plasmin pretreatment. The expression level of laminin returned to normal levels when the slices were cultured for 24-48 hr after washout of plasmin. Furthermore, preincubation with anti-laminin antibodies prevented both the degradation of laminin and the impairment of LTP maintenance by plasmin. These results suggest that the laminin-mediated cell-ECM interaction may be necessary for the maintenance of LTP.

[Home medical care from our hospital]

From April, 1996 to March, 1999, our hospital provided home medical care on a 24-hour basis for fifty patients with advanced or terminal cancer. Eventually, twenty-four patients died at home and twenty-six in the hospital. Stability of health status, the presence of willing and able caregivers, as well as a greater number of house-calls are suggested factors in facilitating a death at home. However, the patients who died in the hospital were obliged to readmit themselves until the time of death due to caregivers' reasons such as fatigue, emotional stress and/or health problems. In addition to timely availability and accessibility of respite care, psychosocial support for family caregivers by liaison nurses remains an issue to be solved in future.

Basic fibroblast growth factor and brain-derived neurotrophic factor promote survival and neuronal circuit formation in organotypic hippocampal culture

Neurotrophic effects in vitro have been generally related to promotion of differentiation, maturation and survival, but little is known about the effect on neuronal circuit formation. The organotypic culture system would be an available technique to investigate neuronal circuit formation and neuronal cell-cell interactions. As we reported previously, an optical recording system is a useful technique to comprehend neuronal activities and circuit from multi-points simultaneously. In this study, we investigated whether continuous application of basic fibroblast growth factor (bFGF or FGF-2) and brain-derived neurotrophic factor (BDNF) inhibited neuronal cell death induced by serum-deprivation in organotypic culture using propidium iodide staining, and we analyzed effects of bFGF and BDNF on the formation of neuronal circuits using the optical recording system. Continuous application of bFGF or BDNF significantly protected the slices from neuronal death. Optical recording also demonstrated that addition of 10 ng/ml bFGF or 50 ng/ml BDNF enhanced optical signals in all hippocampal areas significantly. These data strongly suggest that bFGF and BDNF promote the formation of neuronal circuits as well as survival and that optical recording of organotypic hippocampal slices would be a useful technique that enables us to analyze neuronal circuit formation easily.

Optical recording of trisynaptic pathway in rat hippocampal slices with a voltage-sensitive dye

Changes in membrane potentials were recorded from rat hippocampal slices with a voltage-sensitive dye using a real-time optical recording system, which had high spatial resolution of 128 x 128 points with a high time resolution of 0.6 ms. Serial excitatory propagation was recorded in the dentate gyrus. CA3 and CA1 after stimulation of the perforant pathway, and the optical signals were clearly divided into two components in the dentate gyrus adjacent to the stimulus site. The slow component was suppressed in Ca(2+)-free solution, but the fast component in the molecular layer was not affected. However, the application of 1 microM tetrodotoxin fully abolished both components. These results suggest that the fast and slow components mainly reflect Na(+)-dependent action potentials and excitatory postsynaptic potentials, respectively. The excitatory response duration in the stratum radiatum of CA3 was significantly longer than that in other hippocampal areas. The long-lasting excitation in CA3 is probably related to the CA3 associational projections, because direct stimulation of CA3 pyramidal cell layer also produced similar results. The long-lasting dendritic excitation is probably important to integrate synaptic transmission and may be related to epileptogenesis. When long-term potentiation was induced by a tetanic stimulation (100 Hz for 1 s), the onset latency in the stratum radiatum of CA1 was reduced to as much as 65%, suggesting an increase of excitatory propagation. The analysis of the spatial-temporal optical signals contributes to understanding information processes in the hippocampus, related to learning and memory including long-term potentiation.

The regional vulnerability to blockade of action potentials in organotypic hippocampal culture

We investigated how blockade of spontaneous action potentials influenced the synaptogenesis by measuring the field population spike using hippocampal organotypic cultures. Although respective blockade of inhibitory and excitatory neurotransmission by picrotoxin and CNQX did not significantly induce cell death in all hippocampal area, sodium channel blocking drugs (tetrodotoxin or lidocaine) caused specific and severe damage and affected the formation of functional synapse in CA1 and the entorhinal cortex but not in CA3. It is suggested that the spontaneous action potentials would play a critical role during synaptogenesis.

[Hospice program and palliative medicine]

Hospice and palliative care have important roles for cancer patients in an incurable state to alleviate their total pain and to achieve the best quality of life. Interdisciplinary team-doctors, nurses, therapists, social workers and so on provide effective support in order to fulfill the varying needs of patients and families. Pain relief as a palliative medicine is most urgently required by seventy percent of patients on admission to our Hospice at the Salvation Army Kiyose Hospital. A case is presented with some comments on pain management. Music therapy is also introduced. This is one of the complementary methods for consolation of the mind and body of patients. Some of them seem to find it beneficial.

Optical recording of rat entorhino-hippocampal system in organotypic culture

It is difficult to comprehend the entorhino-hippocampal information processing using acute transverse hippocampal slice, because the dorsally inclined connections of the entorhino-hippocampal projections can be damaged easily. Therefore, we investigated the spatial-temporal propagation in organotypic cultures of the hippocampus attaching to the entorhinal cortex using a real-time optical recording system with a voltage-sensitive dye and suitability as an in vitro model. Real-time imaging demonstrated that the stimulation of the perforant pathway induced excitatory propagation in trisynaptic pathway of the hippocampus and sequentially in the layer V from the medial to the lateral entorhinal cortex. The horizontal propagation from the lateral to the medial site was also seen after the stimulation of the lateral entorhinal cortex. The analysis of the entorhino-hippocampal organotypic culture would contribute to understanding of the mechanism of learning and memory.

3-Hydroxykynurenine toxicity on the rat striatum in vivo

3-Hydroxykynurenine (3-HK) is a tryptophan metabolite whose level in the brain is elevated under several pathological states including Huntington's disease. In the present study, we examined the possible toxicity of 3-HK by injection of this substance into rat brain. Intrastriatal injection of 3-HK (50 nmol) induced tissue damage around the injected site. Quinolinic acid (QA) at 200 nmol also induced tissue damage, which was comparable in size to that induced by 50 nmol 3-HK. Co-administration of MK-801 significantly reduced QA-induced lesion, but failed to prevent 3-HK-induced lesion. On the other hand, the antioxidant N-acetyl-L-cysteine (10 nmol) reduced 3-HK-induced damage. Thus, 3-HK may be involved in brain pathogenesis by providing oxygen radicals.