"Evaluation of neprilysin activity in Adipose-Derived stem cells from Alzheimer's disease patients"

INTRODUCTION

The antibody drugs targeting β-amyloid in Alzheimer's disease pose risks of inflammation and vascular damage. It is known that neprilysin, an endogenous enzyme responsible for β-amyloid degradation, is reduced in areas with β-amyloid deposition. Supplementation of neprilysin could potentially contribute to Alzheimer's disease treatment. When considering the use of adipose tissue-derived stem cells (ADSCs) for Alzheimer's disease therapy, it is crucial to ensure that Alzheimer's disease patient-derived ADSCs maintain neprilysin activity. If so, the use of autologous ADSCs may lead to a treatment with minimal risks of rejection or infection. Therefore, we investigated the neprilysin activity in Alzheimer's disease patient-derived adipose tissue-derived stem cells to assess their potential in Alzheimer's disease treatment.

METHODS

Five Alzheimer's disease patients (MSC1-5) and two Chronic Obstructive Pulmonary Disease (COPD) patients (MSC6-7) were enrolled. ADSCs were cultured for 6 days with varying seeding densities. On the 3rd day, the medium was replaced, and on the 6th day, ADSCs were harvested. Cells were stained for PE-Cy7 Mouse IgG1 κ Isotype control and PE-Cy Mouse Anti-Human CD10, and CD10 expression was assessed by flow cytometry. Ethical approval and informed consent were obtained.

RESULTS

Neprilysin activity, crucial for β-amyloid degradation, was assessed in ADSCs. Positivity rates for CD10 expression in ADSCs from Alzheimer's patients were consistently high: 99.6%, 99.5%, 99.9%, 99.3%, 99.8%, and 100.0%. Control ADSCs from COPD patients (MSC6-7) exhibited comparable positivity rates. Flow cytometry plots for all seven cases are presented in Figures 1-7.

DISCUSSION

This study confirms the presence and maintenance of neprilysin activity in ADSCs from Alzheimer's disease patients. The high positivity rates for CD10 expression in these cells suggest that neprilysin, a key enzyme in β-amyloid degradation, remains active. The implications are significant, as ADSCs offer immune-compatible and low infection risk advantages. The study underscores the potential of autologous ADSCs as a therapeutic approach in Alzheimer's disease. Their ability to naturally harbor neprilysin activity, coupled with their safety profile, makes them a promising candidate for further exploration. While acknowledging the need for larger, more diverse cohorts and long-term studies, these findings contribute to the growing body of evidence supporting the development of stem cell-based interventions in Alzheimer's disease treatment.

Feasibility and Safety of Adjuvant Chemotherapy for Resected Colorectal Cancer in Patients With Renal Insufficiency: A Pooled Analysis of Individual Patient Data from Five Japanese Large-scale Clinical Trials

BACKGROUND/AIM

The incidence of chemotherapy-related adverse events in colorectal cancer patients with renal insufficiency has been compared to patients with normal renal function in only a few studies. The purpose of this analysis was to verify the feasibility and safety of adjuvant chemotherapy for postoperative colorectal cancer patients with renal insufficiency.

PATIENTS AND METHODS

Adverse events and discontinuation of adjuvant chemotherapy for patients with curatively resected locally advanced colorectal cancer were examined using a combined database of individual patient data obtained from five large-scale clinical trials (n=4,106). The renal function of patients was classified into Level (L) 1-2: ≥60 ml/min and L3-4: <60 ml/min.

RESULTS

As Grade 3 adverse events, hematological toxicities, such as neutropenia and anemia, and gastrointestinal disorders, such as diarrhea and vomiting, were significantly more frequent in the L3-4 group. Moreover, the time-to-treatment discontinuation in the L3-4 group was higher (hazard ratio=1.21, p=0.0012). T factor, N factor, and creatinine clearance level were found to be independent risk factors for the discontinuation of adjuvant chemotherapy. In the subgroup analysis of FOLFOX, neutropenia and diarrhea were significantly common in the L3-4 group, but neurotoxicities were not different. There was no significant difference in the discontinuation of adjuvant FOLFOX.

CONCLUSION

Adverse events of adjuvant chemotherapy in patients with resected colorectal cancer were associated with renal insufficiencies. Since adverse events have the potential to shorten the duration of treatment, especially when using chemotherapy without oxaliplatin, careful management, including dose reduction, may be important in patients with renal insufficiency.

Final Analysis of 3 Versus 6 Months of Adjuvant Oxaliplatin and Fluoropyrimidine-Based Therapy in Patients With Stage III Colon Cancer: The Randomized Phase III ACHIEVE Trial

PURPOSE

The phase III ACHIEVE trial conducted in Japan was one of six prospective studies included in the International Duration Evaluation of Adjuvant Therapy collaboration, which explored whether 3 months of adjuvant fluorouracil, leucovorin, and oxaliplatin (FOLFOX) or capecitabine and oxaliplatin (CAPOX) therapy would be noninferior to 6 months of treatment in patients with curatively resected stage III colon cancer. We report the final analyses of survival and long-term safety.

PATIENTS AND METHODS

Eligible patients were randomly assigned (1:1) to either 3 or 6 months of adjuvant chemotherapy (modified [m]FOLFOX6 or CAPOX, as selected by the treating physician). Random assignment was stratified according to number of involved lymph nodes, center, regimen, primary site, and age. The primary end point was disease-free survival, assessed in the modified intention-to-treat population. Overall survival (OS) was a secondary end point.

RESULTS

The modified intention-to-treat population comprised 1,291 patients: 641 in the 6-month treatment group and 650 in the 3-month treatment group. Median follow-up for this analysis was 74.7 months. Five-year OS rates were comparable: 87.0% in the 3-month treatment group and 86.4% in the 6-month treatment group (hazard ratio, 0.91; 95% CI, 0.69 to 1.20; P = .51). Subgroup analysis of OS did not reveal a significant interaction between baseline characteristics and treatment duration. Peripheral sensory neuropathy lasting longer than 5 years was more common in the 6- compared with 3-month treatment group (16% v 8%, respectively), and in those receiving mFOLFOX6 compared with CAPOX (14% v 11%, respectively).

CONCLUSION

In Asian patients, shortening adjuvant therapy duration from 6 to 3 months did not compromise efficacy and reduced the rate of long-lasting peripheral sensory neuropathy. In this setting, 3 months of CAPOX therapy is an appropriate adjuvant treatment option.

Repeated infusion of autologous adipose tissue-derived stem cells for Parkinson's disease

BACKGROUND

Mesenchymal stem cells are expected to have a therapeutic effect on progressive neurodegenerative diseases for which there is currently no fundamental treatment.

AIMS OF THE STUDY

The aim is to confirm that repeated infusion of autologous adipose tissue-derived stem cells (ADSCs) can be safely administered to patients with Parkinson's disease, and to investigate the effects of this as a pilot study.

METHODS

Three patients with Parkinson's disease received five or six repeated infusions of ADSCs at intervals of approximately one month. Observations were based on medical examinations by a neurologist and interviews with the patient and caregivers. The severity of Parkinson's disease was assessed using the Hoehn & Yahr staging scale and Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS).

RESULTS

No adverse events were observed during the observation period from the start of treatment to six months after the end of the last dose. MDS-UPDRS improved in all three patients.

CONCLUSIONS

Repeated administration of Autologous ADSCs for Parkinson's disease was safe and feasible. The results of this pilot study provide insight into the value of further research.

Hypothesis: Intravenous administration of mesenchymal stem cells is effective in the treatment of Alzheimer's disease

We propose the intravenous administration of autologous adipose-derived stem cells as a new treatment for Alzheimer's disease. We hypothesize that the stem cells will secrete neprilysin in the brain to break down and remove amyloid deposits in the Alzheimer's brain. We have shown a case of skin amyloid deposition that disappeared after stem cell administration and confirmed that the stem cells administered had neprilysin activity. In addition to neprilysin secretion, other mechanisms of action of stem cells include nerve regeneration, nerve repair, growth factor secretion, anti-inflammatory effects, and angiogenesis. The harvesting of adipose-derived stem cells is minimally invasive, and intravenous administration can be safely repeated. We hope that the efficacy of this new treatment will be verified and that it will bring a ray of hope to patients suffering from this incurable disease.

Isolation of adipose tissue-derived stem cells by direct membrane migration and expansion for clinical application

Mesenchymal stem cells (MSCs) have recently made significant progression in multiple clinical trials targeting several clinical disorders and in the modulation of immune responses. In the present study, we isolated human adipose tissue-derived stem cells (ADSCs) by direct membrane migration method without using enzymatic digestion via collagenase, and tried to extract adequate number of cells for clinical application. Hydroxyapatite-treated nonwoven fabric membrane made up of synthetic macromolecular fiber materials, polyethylene and polyester terephthalene was used. Expansion culture of ADSCs having plastic flask adherent characteristic in serum-free condition was successfully established, and adequate number of cells were obtained for clinical application. They were found to be positive for CD44, CD73, CD90 and CD105 and negative for CD11b, CD34, CD45, CD80 and HLA-DR. The resulting immunological marker profile satisfied the immunophenotype of previously reported MSCs. Also, microscopic findings demonstrated trilineage differentiation into adipogenic, osteogenic and chondrogenic cells as the characteristics of MSCs. The isolation by nonwoven fabric membrane and expanded cells under serum-free condition satisfied the criteria of MSCs, as proposed by the International Society for Cellular Therapy. Our direct membrane migration method without enzyme digestion is useful as ADSCs can be obtained from small pieces of adipose tissue and expanded under serum-free culture condition. This method was considered to be feasible for clinical application.

Perspectives on Stem Cell-Based Regenerative Medicine with a Particular Emphasis on Mesenchymal Stem Cell Therapy

Regenerative medicine is a medical treatment that aims to restore lost human body functions by regenerating missing or dysfunctional organs and tissues using stem cells, etc. There are three major types of stem cells used in regenerative medicine: induced pluripotent stem cells (iPS cells), embryonic stem cells (ES cells), and mesenchymal stem cells (MSCs). MSCs are expected to be widely applied to regenerative medicine because of their ability to differentiate into various types of cells, repair cells and tissues; anti-inflammatory effects; secretion of various growth factors; and resolution of abnormally accumulated protein amyloid. MSCs can be derived from bone marrow, dental pulp, and other sources, but adipose tissue-derived stem cells (ADSCs) may be superior in that they can be harvested with the least amount of invasion, and therefore, a sufficient amount of stem cells can be cultured relatively easily. When MSCs are administered systemically by intravenous infusion, they tend to accumulate at the site of disease, a property known as “homing,” which is extremely advantageous for clinical applications. In Japan, stem cell therapy can be performed only after the research or treatment plan has been reviewed and approved by the “Committee for Specific Approval of Regenerative Medicine” and submitted to the Ministry of Health, Labor and Welfare for approval in accordance with the “Act on Securing the Safety of Regenerative Medicine” and after approval by the ethics committee of the facility where the therapy is performed. In this review, the characteristics of MSCs, the actual status of their clinical application, and their future prospects are presented.

Geriatric nutritional risk index (GNRI) predicts long-term survival and limb events in patients with peripheral artery disease

Background

Geriatric nutritional risk index (GNRI) was developed as a “nutrition-related” risk index and was reported in different populations as associated with the risk of all-cause and cardiovascular morbidity and mortality.

Purpose

The purpose of this study was to assess the associations of GNRI with mortality and amputation free survival in patients with peripheral artery disease (PAD).

Methods

From January 2011 to June 2016, 295 consecutive patients (73.3±9.2 years; 75.6% male) with PAD undergoing endovascular treatment (EVT) in our hospital were retrospectively examined. The GNRI on admission was calculated as follows: 14.89 × serum albumin (g/dl) + 41.7 × body mass index (BMI)/22. Characteristics and mortality were compared between 2 groups: low GNRI (&lt;92, n=110) with moderate or severe nutritional risk; and high GNRI (≥92, n=185) with no or low nutritional risk.

Results

The median follow up period was 39.4±26.4months. There were 85 deaths (28.8%) and 13 major amputation (4.4%) during the follow-up. Patients in the low-GNRI group were more often higher age, non-ambulatory state, hemodialysis and critical limb ischemia. BMI, serum hemoglobin, albumin, low-density lipoprotein were significantly lower, whereas serum C-reactive protein was significantly higher in the low-GNRI group than the high-GNRI group (P&lt;0.05, respectively). Kaplan–Meier analysis revealed that patients in the low-GNRI group had a significantly lower amputation free survival, compared to those in the high-GNRI group (log-rank test, P&lt;0.001).

Conclusion

The low GNRI is associated with an increased risk of mortality and limb events in patients with PAD.

Amputation-free survival (Kaplan-Meier)

Funding Acknowledgement

Type of funding source: None

P179 Alterations of resting heart rate and heart rate viability after cryoballon ablation in the patients with paroxysmal atrial fibrillation

Background

While it is generally accepted that cardiac autonomic nervous system (CANS) plays an important role in atrial fibrillation (AF) and pulmonary vein isolation (PVI) by radiofrequency catheter ablation modifies the ganglionated plexi (GP), the alterations of CANS after PVI are not clarified.

Purpose

The objective of this study was to investigate the alteration of CANS after conventional cryoballoon ablation (CBA) by using a non-invasive examination method of measuring resting heart rate (R-HR) and coefficient of variation of R-R interval (CVR-R) which is a representative parameter of heart rate viability. CVR-R reflects R-R interval variation affected by respiration. It is calculated from the R-R interval of consecutive 100 heart beats of sinus rhythm recorded at rest. Declines of CVR-R indicate the parasympathetic dysfunction and the normal range of it varies depend on the age. As age increases from 30s to 70s, the average value of CVR-R decreases from 4.0% to 2.4%.

Methods

Consecutive patients of paroxysmal AF treated with initial CBA in our institute participated. Subjects were limited to the patients who maintained sinus rhythm through the study and whose prescription had not been changed after procedure. All patients recorded 12-lead electrocardiogram to measure R-HR and CVR-R before and the day after the procedure. We compared R-HR and CVR-R of all patients before and after CBA. And in addition, we compared them in each of two groups whose pre-procedural H-RH were under 50 bpm (Group-U50) and over 70 bpm (Group-O70). All procedures were performed with second generation 28mm cryoballoon (CB)s under the conscious sedation with Dexmedetomidine. CB temperature was down to a minimum of -60°C and target application time was 180 seconds.

Results

In the procedure of all 105 patients (male gender, 54%; age, 66.9 ± 10.4years; CHADS2score, 1.15 ± 1.04; diabetes mellitus,14%; beta-blocker therapy, 16%), 1 of touch-up for PVI, 6 of supra vena cava isolation and 21 of cavotricuspid isthmus linear ablations with radiofrequency catheter were added. In all patients, R-HR increased from 58.9 ± 9.2bpm to 72.4 ± 9.5bpm (P &lt; 0.01) and CVR-R decreased from 2.36 ± 1.08% to 1.24 ± 0.68% (P &lt; 0.01), respectively. In Group-U50 (n = 14; male gender 64%; age 67.6 ± 12.4 years), R-HR increased from 47.1 ± 2.1bpm to 64.4 ± 7.9bpm (P &lt; 0.01) and CVR-R decreased from 2.58 ± 1.59% to 1.34 ± 0.82% (P &lt; 0.01), respectively. In Group-O70 (n = 17; male gender 43%; age 67.4 ± 12.6 years), R-HR increased from 73.7 ± 2.8bpm to 81.8 ± 7.4bpm (P &lt; 0.01) and CVR-R decreased from 2.33 ± 0.94% to 1.14 ± 0.52% (P &lt; 0.01), respectively. Values of CVR-R before and after CBA showed no significant difference between the two groups.

Conclusions

After CBA, R-HR increment and CVR-R decrement were significantly observed. CVR-R was halved regardless of pre–procedural R-HR. Damages to GP by CBA would be reflected as denervation of vagus nerves in CANS. R-HR increase might be associated with parasympathetic suppression of CANS.

In Situ Tissue Engineering of the Bile Duct Using Polypropylene Mesh-Collagen Tubes

Multiple attempts have been made to replace biliary defects with a variety of materials. Recently, successful biliary reconstruction using the Gore-Tex vascular graft has been reported experimentally and clinically We designed a new artificial bile duct consisting of collagen sponge and polypropylene mesh. We presently evaluated the feasibility of using this prosthesis as a scaffold for bile duct tissue regeneration in a canine model. Our prosthesis, a sponge made from porcine dermal collagen, is reinforced with a polypropylene mesh cylinder. We used the prosthesis to reconstruct the middle portion of the common bile duct in seven beagle dogs to evaluate its efficacy. While one dog died of biliary stricture 8 months after operation, six survived without problems to scheduled time points for tissue evaluation at 1 to 12 months. All prostheses had become completely incorporated into the host. A confluent epithelial lining was observed within 3 months. In cholangiograms the prosthesis displayed long-term patency in the six dogs and provided satisfactory bile drainage for up to 12 months. Our graft thus shows promise for repair of biliary defects and should lead to development of a new treatment for biliary reconstruction.

Successful lung transplantation in a case with diffuse pulmonary arteriovenous malformations and hereditary hemorrhagic telangiectasia

Diffuse pulmonary arteriovenous malformations (AVMs) are associated with a poor prognosis and the therapeutic strategy remains controversial. We describe a pediatric patient with diffuse pulmonary AVMs associated with hereditary hemorrhagic telangiectasia (HHT), who presented with two cerebral AVMs in the parietal and occipital lobes as well. Of note, successful bilateral lung transplantation not only improved the hypoxemia but also resulted in size reduction of the cerebral AVMs. Although it is essential to consider involvements other than pulmonary AVMs, especially brain AVMs, to decide the indication, lung transplantation can be a viable therapeutic option for patients with diffuse pulmonary AVMs and HHT.

Variations in the structure and transcription of the mitochondrial atp and cox genes in wild Solanum species that induce male sterility in eggplant (S. melongena)

In order to determine the molecular basis of cytoplasmic male sterility (CMS) in alloplasmic lines of eggplant, the genomic structures and transcription patterns of mitochondrial ATP synthase subunit (atp) and cytochrome oxidase subunit (cox) genes were studied for wild and cultivated eggplants. Alloplasmic eggplant lines with cytoplasms of wild Solanum species showing either anther indehiscent type of CMS or non-pollen production type of CMS were studied with the cultivated eggplant Solanum melongena, used as a control. Southern hybridization of the mitochondrial genes indicated the difference between the two types of CMS and showed complete identity within each type. The cytoplasmic patterns of all wild species differed from that of the cultivated eggplant. Thus, the cytoplasm of the six wild eggplants and the one cultivated eggplant was classified into three groups. Male sterile plants of both types of CMS showed novel transcription patterns of atp1, whereas a different transcription pattern of cox2 was observed only in the anther indehiscent type. Based on these differences, we determined the DNA sequences of about a 4 kbp segment in the atp1 region. Although the coding and 3' flanking regions were almost identical among the cytoplasms, the 5' flanking region was completely different and novel open reading frames (orfs) were found for each of the CMS types and the cultivated eggplant. The cytoplasm of Solanum kurzii inducing the anther indehiscent type CMS had orf312, and those of Solanum aethiopicum and Solanum grandifolium of non-pollen production type CMS had orf218. The correspondence between the transcription patterns of these orfs and phenotypic expression of male sterility strongly suggests that these orfs are causal genes for each type of CMS.

[A new strategy for locally advanced rectal cancer using a nerve-regeneration tube]

In surgery for the treatment of locally advanced rectal cancers affecting the intrapelvic nerves, when an affected nerve is resected in extended surgery to achieve radical cure, the resection results in functional disturbance in the organ it controls. On the other hand, when the nerve remains intact after function-preserving surgery, the risk of local recurrence is high because of possible remnant cancer cells. Thus in performing surgery to treat such cancers, there is a dilemma between the selection of extended surgery or function-preserving surgery. To resolve this, we devised a new strategy in which the cancer is removed radically in extended surgery and organ function is recovered by regeneration of the resected nerve using a nerve-regenerating tube. After animal experiments had confirmed the regeneration of nerve functions with nerve-regenerating tubes, we followed this new strategy to treat 17 patients with locally advanced cancers who underwent extended surgery plus the regeneration of the resected nerve using the nerve-regenerating tube. Nerve function was restored to a significant degree in 16 of the 17 patients.

Abstract 5365: Prolonged survival of patients with advanced renal cancer responding to multi-peptide vaccine IMA901 after single-dose cyclophosphamide

Translational research and the clinical development of therapeutic cancer vaccines requires stronger scientific rationalization. Here we demonstrate how immune response markers as well as biomarkers defining the immune regulatory environment were utilized as guiding tools from discovery to advanced clinical trials of IMA901, a novel therapeutic vaccine for the treatment of renal cell carcinoma (RCC). IMA901 consists of multiple tumor-associated peptides (TUMAPs) confirmed to be naturally presented in human RCC tissue by mass spectrometry, selected using differential transcriptomics and preclinically validated by systematic analysis of immunogenicity with artificial antigen-presenting cells. Two consecutive independent clinical studies in a total of 96 HLA-A*02+ advanced/metastatic RCC patients were conducted. The phase I study revealed that T-cell responses to multiple IMA901 antigens were significantly associated with disease control and negatively associated with the presence of FoxP3+ regulatory T cells (Tregs). The subsequent randomized phase II study demonstrated that pre-treatment with a single low dose of cyclophosphamide (Cy) reduced Treg frequencies and prolonged overall survival (OS) in patients who mounted an immune response to the IMA901 vaccine. Additionally, T-cell responses to multiple IMA901 antigens were again associated with clinical benefit. Furthermore, a comprehensive prognostic and predictive biomarker program was conducted. Among cellular biomarkers, highly significantly elevated levels of myeloid-derived suppressor cells (MDSC), IL-17-/IL-10-secreting T cells and dysfunctional T cells in RCC patients vs. healthy individuals were found. Two MDSC populations (CD14+ HLA-DR- and CD14- CD11b+ CD15+) were significantly negatively associated with survival in vaccinated RCC patients. Interestingly, both MDSC populations were also found to be negatively associated with OS in an independent trial in colorectal cancer patients (N=79) implying a broader role for these MDSC species. Additionally, among over 300 serum biomarkers tested, apolipoprotein A-I (ApoA1) and the chemokine CCL17 were found to be predictive for both immune responses to IMA901 and survival of the RCC patients. The knowledge acquired in these trials was used to design a randomized phase III study. In this ongoing study, IMA901 is combined with the tyrosine kinase inhibitor sunitinib based on the findings that sunitinib downmodulates the two MDSC populations described above. Furthermore, in this phase III study, the relevance of ApoA1/CCL17 will be explored by prospectively defined subgroup analyses.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5365. doi:1538-7445.AM2012-5365

Pluripotency of a polyploid H1 (ES) cell system without leukaemia inhibitory factor

OBJECTIVES

Tetraploid cells are strictly biologically inhibited from composition of embryos; by the same token, only diploid cells compose embryos. However, the distinction between diploid and tetraploid cells in development has not been well explained. To examine pluripotency of polyploid ES cells, a polyploid embryonic stem (ES)-cell system was prepared.

MATERIALS AND METHODS

Diploid, tetraploid, pentaploid, hexaploid, octaploid and decaploid H1 (ES) cells (2H1, 4H1, 5H1, 6H1, 8H1 and 10H1 cells, respectively) were cultured for about 460 days in L15F10 medium without leukaemia inhibitory factor (LIF). The cells cultured under LIF-free conditions were denoted as 2H1(-), 4H1(-), 5H1(-), 6H1(-), 8H1(-) and 10H1(-) cells, respectively. Pluripotency and gene expression were examined.

RESULTS

Ploidy alteration of H1(-) cells was similar to that of H1 cells. The polyploid H1(-) cells showed positive activity of alkaline phosphatase, suggesting that they maintained pluripotency in vitro without LIF. The polyploid H1(-) cells formed teratocarcinomas in mouse abdomen, suggesting they could differentiate in mouse abdomen in vivo. 2H1, 4H1 and polyploid H1(-) cells expressed nanog, oct3/4 and sox2 genes, suggesting that they fulfilled the criteria of ES cells. Nanog gene was significantly over-expressed in 4H1 and polyploid H1(-) cells, suggesting that overexpression of nanog gene was a characteristic of polyploid H1 cells.

CONCLUSION

Polyploid H1 (ES) cells retained pluripotency in vitro, without LIF with nanog over-expression.

Regeneration and functional recovery of intrapelvic nerves removed during extensive surgery by a new artificial nerve conduit: a breakthrough to radical operation for locally advanced and recurrent rectal cancers

PURPOSE

In the current strategy against locally advanced and recurrent rectal cancers possibly involving intrapelvic nerves, there has been a serious dilemma between extensive surgery and limited surgery. The former can attain high tumor curability by sacrificing the nerve functions while the latter prioritizes the patient quality of life by preserving the nerve functions but with a compromised curability. Here we present a new surgical strategy for locally advanced and recurrent rectal cancers, which realize both high tumor curability and good quality of life.

METHODS

A new artificial nerve conduit (polyglycolic acid collagen tube) developed by in site tissue engineering technology was applied to recovery the disturbed functions after removing the nerves from 11 patients undergoing extensive surgery for intrapelvic advanced or recurrent colorectal cancers. The reconstructed nerves included eight autonomic nerves which are essential for the genitourinary function and three somatic nerves which control the sensation and mobility of the legs.

RESULTS

Out of ten cases followed up more than 2 years and evaluated fully, eight including two report cases showed a functional recovery of the disturbed autonomic and somatic nerves clinically. The nerve function started to recover from 3 to 6 months after the operation and continued to improve with times. No specific complications associated with the nerve repair have been noted.

CONCLUSIONS

The new strategy utilizing the nerve conduit can be a breakthrough in radical operations for locally advanced and recurrent rectal cancers to resolve the problems between tumor curability and the patient quality of life.

DNA-unstable decaploid mouse H1 (ES) cells established from DNA-stable pentaploid H1 (ES) cells polyploidized using demecolcine

OBJECTIVES

DNA content of diploid H1 (ES) cells (2H1 cells) has been shown to be stable in long-term culture; however, tetraploid and octaploid H1 (ES) cells (4H1 and 8H1 cells, respectively) were DNA-unstable. Pentaploid H1 (ES) cells (5H1 cells) established recently have been found to be DNA-stable; how, then is cell DNA stability determined? To discuss ploidy stability, decaploid H1 (ES) cells (10H1 cells) were established from 5H1 cells and examined for DNA stability.

MATERIALS AND METHODS

5H1 cells were polyploidized using demecolcine (DC) and 10H1 cells were obtained by one-cell cloning.

RESULTS

Number of chromosomes of 10H1 cells was 180 and durations of their G(1), S, and G(2)/M phases were 3, 7 and 6 h respectively. Volume of 10H1 cells was double that of 5H1 cells and morphology of 10H1 cells was flagstone-like in shape. 10H1 cells exhibited alkaline phosphatase activity and their DNA content decayed in 91 days of culture. 10H1 cells injected into mouse abdomen formed solid tumours that contained several kinds of differentiated cells with lower DNA content, suggesting that 10H1 cells were pluripotent and DNA-unstable. Loss of DNA stability was explained using a hypothesis concerning DNA structure of polyploid cells as DNA reconstructed through ploidy doubling was arranged in mirror symmetry in a new configuration.

CONCLUSION

In the pentaploid-decaploid transition of H1 cells, cell cycle parameters and pluripotency were retained, but morphology and DNA stability were altered.

Multicenter phase II study of weekly paclitaxel plus S-1 combination chemotherapy in patients with advanced gastric cancer

BACKGROUND

A multicenter phase II study was conducted to evaluate the efficacy and safety of a combination regimen of weekly paclitaxel plus S-1 in patients with advanced gastric cancer.

METHODS

Patients with previously untreated metastatic or recurrent gastric cancer received intravenous paclitaxel 50 mg/m(2) on days 1, 8, and 15, plus oral S-1 40 mg/m(2) b.i.d. on days 1 to 14 followed by 2 weeks off, in a 28-day cycle.

RESULTS

A total of 54 patients were registered. All of them had measurable disease and were determined to be eligible for the present study. Two complete responses and 23 partial responses were confirmed, giving an overall response rate of 46.3%. At a final follow up of 3 years, the median progression-free survival and median overall survival were 6.0 and 14.3 months, respectively. Grade 3 neutropenia occurred in 14 patients, and grade 4 in 1 patient (total, 27.8%). The most serious nonhematological toxicity was diarrhea, where grade 3 occurred in 5 patients (9.3%). There were no treatment-related deaths.

CONCLUSION

A combination of weekly paclitaxel plus S-1 was found to be well tolerated and effective in patients with advanced gastric cancer. Further investigation with comparative trials is needed for confirmation.

Gastric hyposecretion in esophageal squamous-cell carcinomas

Recently, gastric fundic atrophy is reported to be an independent risk factor for esophageal squamous-cell carcinoma (ESCC). The aim of this study is to investigate the acid secretory level in ESCC in a case-control study. From April 2004 to March 2008, 100 consecutive subjects with early ESCC and 100 age- and sex-matched asymptomatic controls were prospectively enrolled. Gastrin-stimulated acid output was assessed by endoscopic gastrin test. Conditional regression analyses were used to adjust for other potential confounders. Multivariate analyses revealed a strong association between profound hypochlorhydria and ESCC with odds ratio (95% confidence interval): 6.0 (1.9-18.4). The association remained significant after adjusting for the effect of gastric atrophy as a covariate. The association became stronger as the ESCC developed more distal site of the esophagus. This study indicates that profound hypochlorhydria is a strong independent risk factor for ESCC even after adjusting for the influence of gastric atrophy.

Development of a laser-focused ion beam combination machine

We have developed a laser and focused ion beam (FIB) compound system to process an optical component device with an ultrafine precision minute surface structure and a micromedical device. This machine consists of an FIB and three types of lasers with an atomic force microscope. This system can fabricate decamicrometer area by laser and submicrometer area by FIB at one chuck. When processing the press mold die of a microlens array (10x10) in a glasslike carbon with a femtosecond laser, a diameter of 3.2 microm and depth of 0.43 microm are obtained. However, the surface roughness is more than Rz=0.5 microm. After this process, we finished this surface with the use of the FIB. As a result, the surface roughness is less than Rz=0.05 microm.

Histologic and electrophysiological study of nerve regeneration using a polyglycolic acid-collagen nerve conduit filled with collagen sponge in canine model

OBJECTIVES

To determine the rate of achieving electrophysiologically proved functional recovery by autonomic nerve regeneration, with the aid of an artificial nerve conduit.

METHODS

A polyglycolic acid (PGA) collagen nerve conduit filled with collagen sponge was interposed in a 10-mm-long gap of the right hypogastric nerve (HGN) in 16 dogs. Histologic evaluation of nerve regeneration and electrophysiological analysis at 2 weeks and 2, 3, 4, 5, 6, 7, and 8 months (n = 2, each) after surgery was performed, measuring the responses for the spermatic ducts (SD), bladder neck (BN), and prostate contraction, by stimulating the right lumbar splanchnic nerves (LSNs) from L2 to L4, after transection of the left HGN to eliminate substitutive pathways.

RESULTS

Two months after implantation, the regenerated neurofilaments were successfully extended through the graft from the proximal-to-distal direction. In 2 control dogs, electrostimulation of the right LSNs induced elevation of the intraluminal pressure of the SD, elevation of the BN pressure, and prostate contraction. No responses were observed in all dogs up to 6 months of follow-up after implantation. In 1 dog with a 7-month follow-up, electrostimulation elicited elevation of BN pressure alone. In both dogs with an 8-month follow-up, electrostimulation induced similar responses to control in all SD, BN, and prostate; however, after excision of the area of the interposed right HGN, no response was observed.

CONCLUSIONS

These results proved that regeneration of a 10-mm gap of the HGN, using a novel PGA-collagen nerve conduit could be achieved within 8 months.

Regeneration of peritoneum using amniotic membrane to prevent postoperative adhesions

BACKGROUND/AIMS

Adhesions following intraperitoneal surgery are frequent causes of small bowel obstruction. Attempts to prevent postoperative adhesions have mostly proven disappointing clinically. Currently used by ophthalmologists in ocular surface disorders, amniotic membrane transplantation can reduce inflammation and promote re-epithelization. We used amniotic membrane for facilitating peritoneal regeneration and prevention of adhesions with surgical trauma.

METHODOLOGY

20 rats were randomized in equal number into treatment or control groups. Seven days after operation, the incidence and severity of adhesions were evaluated. Histologic and immunohistochemical analyses were examined at 1, 4, 10 weeks after operation.

RESULTS

While severe adhesions were observed after 1 week between the cecum and surrounding organs in the control group, adhesion formation was significantly reduced in the amniotic membrane group. Histologic examination demonstrated that free-floating myofibroblasts in the peritoneal cavity attached to surfaces of amniotic membrane grafts to form a layered structure. Free-floating mesothelial cells were incorporated into the regenerating mesothelium on the myofibroblast layer in 4 weeks, while implanted amniotic membrane grafts were absorbed by 10 weeks. In the amniotic membrane group the cecum appeared nearly normal.

CONCLUSIONS

Amniotic membrane grafts reduced intraperitoneal adhesions after surgical trauma, were well absorbed, and served as a substrate for regenerating mesothelium.

Involvement of REG Ialpha protein in the regeneration of ductal epithelial cells in the minor salivary glands of patients with Sjögren's syndrome

The regenerating gene (Reg) was originally isolated from regenerating rat pancreatic islets and revealed recently to constitute a multi-gene family in humans. REG Ialpha protein is known to be overexpressed not only in various human inflammatory diseases but also in various experimental models of inflammation in animal tissues. However, its involvement in pathophysiology of the minor salivary gland (MSG) is not clear. We investigated REG Ialpha expression in the MSG of patients with primary Sjögren's syndrome (SS) and assessed its role in ductal epithelial cell proliferation in such tissues. Lip biopsy specimens were obtained from 40 patients with primary SS and examined using immunohistochemistry for REG Ialpha protein, Ki67 and single-strand DNA (ssDNA). The relationships among clinicopathological factors and expression of REG Ialpha protein, Ki67 and ssDNA in the MSG were then analysed. REG Ialpha protein was expressed rarely in ductal epithelial cells of the normal MSG but was apparently overexpressed in those of patients with SS. The labelling indices for both Ki67 and ssDNA in the ductal cells of the MSGs were significantly higher in SS patients than in controls. Moreover, these labelling indices were significantly higher in REG Ialpha-positive than in negative SS patients. REG Ialpha protein may play a role in the regeneration of ductal epithelial cells in the MSGs of patients with SS.

Establishment of a tetraploid Meth-A cell line through polyploidization by demecolcine but not by staurosporine, K-252A and paclitaxel

Polyploid cells are made by DNA reduplication without cell division, however, it is not easy to establish polyploid mammalian cell lines. It is worth studying the difference in cell character between hyperploid and parent cell lines. Meth-A cells were polyploidized by demecolcine, K-252a, staurosporine and paclitaxel. The cell-cycle responses of highly polyploid Meth-A cells after the removal of the drugs were examined by flow cytometry (FCM). Meth-A cells were highly polyploidized by these drugs. The polyploid Meth-A cells gradually decreased in ploidy after the drug release. A tetraploid Meth-A cell line was established only from the demecolcine-induced polyploid Meth-A cells. The duration of G1, S and G2/M phases of the tetraploid cell line were mostly the same as those of the parent diploid cells, except that the G2/M phase was 1.5 h longer. The chromosome number of tetraploid Meth-A cell line was about twice of the diploidy. A tetraploid Meth-A cell line was established.

Intrathoracic esophageal replacement by in situ tissue-engineered esophagus

OBJECTIVE

This study aimed to evaluate in situ tissue-engineered esophagus in a canine model after experimental resection and replacement of a full circumferential defect of the intrathoracic esophagus.

METHODS

Two types of scaffolding were fabricated. In the KF(+) group (n = 6), oral keratinocytes and fibroblasts cultured on human amniotic membrane were sheeted on polyglycolic acid felt with smooth muscle tissue and were then rolled around tubes. In the KF(-) group (n = 6), the same procedure was followed, but the keratinocytes and fibroblasts were omitted. Both scaffolds were wrapped in omentum and implanted in the abdomen. In the KF(+) group, at 3 weeks after implantation, the scaffold developed into a tube with a well-differentiated lumen of stratified squamous cells surrounded by a thick smooth muscle-like tissue (in situ tissue-engineered esophagus). A part of the esophagus was resected and replaced by the graft in the same dogs.

RESULTS

In the KF(-) group, strictures developed after esophageal replacement, with almost complete obstruction within 2 to 3 weeks. In contrast, in the KF(+) group, the in situ tissue-engineered esophagus showed good distensibility and the dogs remained without feeding problems through 420 days. Esophageal peristalsis transferred food to the stomach, despite the absence of peristaltic activity in the in situ tissue-engineered esophagus itself. The thickness of the squamous epithelial layer and the smooth muscle layer of the in situ tissue-engineered esophagus were similar to that of the adjacent native esophagus.

CONCLUSION

The in situ tissue-engineered esophagus can successfully replace the intrathoracic esophagus, and this procedure may offer a promising surgical approach to esophageal diseases.

Efficacy of prophylactic extended lymphadenectomy with gastrectomy for patients with node-negative advanced gastric carcinoma

BACKGROUND/AIMS

Extended lymphadenectomy with gastrectomy is widely performed for patients with advanced gastric carcinoma. However, the therapeutic value of prophylactic extensive lymphadenectomy in patients with node-negative advanced gastric cancer is controversial.

METHODOLOGY

We retrospectively analyzed 221 patients who underwent curative gastrectomy for advanced gastric carcinoma without lymph node metastasis to evaluate the effect of prophylactic extended lymphadenectomy on postoperative survival. The postoperative survival rate of patients who underwent extended lymphadenectomy was compared with that of patients who underwent limited lymphadenectomy. Predictive risk factors for tumor recurrence and recurrent patterns also were analyzed.

RESULTS

Extended lymphadenectomy improved the postoperative survival rate of patients with advanced tumors even when lymph node spread was absent. Whether or not prophylactic extended lymphadenectomy was performed significantly affected tumor recurrence in patients with node-negative advanced gastric carcinoma.

CONCLUSIONS

Extensive lymphadenectomy with gastrectomy prolongs survival of patients with node-negative advanced tumors.

Overexpression of RegIV in peritoneal dissemination of gastric cancer and its potential as A novel marker for the detection of peritoneal micrometastasis

BACKGROUND

Regenerating gene type IV (RegIV) is a candidate marker for cancer and inflammatory bowel disease. In this study, its potential as a novel marker for the detection of gastric cancer peritoneal micrometastases was examined.

PATIENTS AND METHODS

RegIV mRNA levels in the peritoneal washes of 95 gastric cancer patients and 22 with benign disease were quantified by real-time RT-PCR. To examine whether expression of RegIV enhance tumorigenicity or not, thirty two mice were injected intraperitoneally or subcutaneously with RegIV transfectants of TMK-1 cells, parental TMK-1 cells, or neomycin control transfectants.

RESULTS

RegIV expression was markedly higher in patients with peritoneal metastases compared to those without. The level of RegIV mRNA in gastric cancer patients was related to the extent of wall penetration. A cut-off value for RegIV-positive expression was based on an analysis of negative control patients with benign disease, and gastric cancer patients above the cut-off value constituted the micrometastasis (MM+) group. Based on this criteria, 3 out of 43 T1 or T2 cases were MM+ (93% specificity). Among 15 patients with peritoneal dissemination (7 out of 15 cases were positive by cytology), 14 cases were positive for RegIV expression (93% sensitivity), while analysis of carcinoembryonic antigen (CEA) mRNA failed to detect micrometastases in 4 cases (73% sensitivity). Combined analysis of CEA and RegIV improved the accuracy of diagnosis to 100%. The prognosis of RegIV-positive cases was significantly worse than that of RegIV-negative cases. Multivariate analysis using the Cox proportional hazards model suggested that RegIV may be an independent prognostic factor. Stable expression of RegIV significantly enhanced peritoneal metastasis in an animal model of gastric cancer.

CONCLUSION

These findings suggest that RegIV mRNA expression has the potential to serve as a novel marker for detecting peritoneal dissemination in gastric cancer.

Nanogel DDS enables sustained release of IL-12 for tumor immunotherapy

For a valid cytokine immunotherapy of malignancies, a suitable delivery system that ensures slow-release of cytokines is required, because short half-life in vivo of the molecules ruins therapeutic efficacy while causing severe systemic toxic effects. We previously showed that the cholesterol-bearing pullulan (CHP)-based hydrogel nanoparticles, or nanogel, encapsulates, stabilizes and releases various molecules. Here we applied this nanogel to administration in vivo of interleukin-12 (IL-12). Recombinant murine IL-12 (rmIL-12) was successfully incorporated into CHP nanogel simply by incubated with CHP at room temperature. After subcutaneously injected into mice, the CHP/rmIL-12 complex led to a prolonged elevation in IL-12 concentration in the sera. Repetitive administrations of the CHP/rmIL-12, but not rmIL-12 alone, induced drastic growth retardation of preestablished subcutaneous fibrosarcoma without causing any serious toxic event. The present study proposes a novel therapeutic intervention technology, taking advantage of slow and sustained release of bioactive cytokines from the self-assembling biocompatible nanoparticles.

Chloride ions control the G1/S cell-cycle checkpoint by regulating the expression of p21 through a p53-independent pathway in human gastric cancer cells

The aim of the present study is to investigate whether the chloride affects cell growth and cell-cycle progression of cancer cells. In human gastric cancer MKN28 cells, the culture in the Cl(-)-replaced medium (replacement of Cl(-) by NO(3)(-)) decreased the intracellular chloride concentration ([Cl(-)](i)) and inhibited cell growth. The inhibition of cell growth was due to cell-cycle arrest at the G(0)/G(1) phase caused by diminution of CDK2 and phosphorylated Rb. The culture of cells in the Cl(-)-replaced medium significantly increased expressions of p21 mRNA and protein without any effects on p53. These observations indicate that chloride ions play important roles in cell-cycle progression by regulating the expression of p21 through a p53-independent pathway in human gastric cancer cells, leading to a novel, unique therapeutic strategy for gastric cancer treatment via control of [Cl(-)](i).

Regeneration of skeletal muscle using in situ tissue engineering on an acellular collagen sponge scaffold in a rabbit model

Because of the limited ability of skeletal muscle to regenerate, resection of a large amount of muscle mass often results in incomplete recovery due to nonfunctional scar tissue. The aim of this study was to regenerate skeletal muscle using in situ tissue engineering in a rabbit model. In 18 male rabbits, a muscle defect (1.0 x ~1.0 x ~0.5 cm) was created in the vastus lateralis of both legs. A piece of cross-linked atelocollagen sponge was then inserted into the defect in one leg, whereas the defect in the other leg was left untreated. Both defects were finally covered with fascia. Twenty-four weeks after surgery, the defect that had been filled with the cross-linked atelocollagen sponge scaffold showed mild concavity and slight adhesion to the fascia, while the control side showed severe scar formation and shrinkage. Histologically, the regenerating myofibers at the site containing the collagen sponge were greater in number, diameter, and length than those at the control site. These results indicate that cross-linked atelocollagen sponge has the potential to act as a scaffold for muscle tissue regeneration.

Lack of synchrony among multiple nuclei induces partial DNA fragmentation in V79 cells polyploidized by demecolcine

The nuclear morphology of polyploidized cells was examined in V79 Chinese hamster cells polyploidized by demecolcine or K-252a, inhibitors of spindle fibre formation and protein kinases, respectively. A variety of nuclear morphologies, including multinuclei, were observed in V79 cells polyploidized by demecolcine but not by K-252a, which produced mononuclear cells. A lack of synchrony in the nuclear cycle was observed among nuclei in multinuclear polyploidized cells. Partial DNA fragmentation, defined as DNA fragmentation of a nucleus in a multinuclear cell, was detected using the TUNEL method in V79 cells polyploidized by demecolcine but not by K-252a. Apoptosis occurred earlier in cell populations treated with demecolcine than in these treated with K-252a once the drugs were removed from the medium, suggesting that polyploidized cells with separate nuclei tend to apoptose earlier than those with mononuclei.