Dendritic cells pulsed with penetratin-OLFM4 inhibit the growth and metastasis of melanoma in mice.

Cancer stem cells (CSCs) can self-renew and differentiate, contributing to tumor heterogeneity, metastasis, and recurrence. Their resistance to therapies, including immunotherapy, underscores the importance of targeting them for complete remission and relapse prevention. Olfactomedin 4 (OLFM4), a marker associated with various cancers such as colorectal cancer, is expressed on CSCs promoting immune evasion and tumorigenesis. However, its potential as a target for CSC-specific immunotherapy remains underexplored. The primary aim of this study is to evaluate the effectiveness of targeting OLFM4 with dendritic cell (DC)-based vaccines in inhibiting tumor growth and metastasis. To improve antigen delivery and immune response, OLFM4 was conjugated with a protein-transduction domain (PTD) from the antennapedia of Drosophila called penetratin, creating a fusion protein (P-OLFM4). The efficacy of DCs pulsed with P-OLFM4 (DCs [P-OLFM4]) was compared to DCs pulsed with OLFM4 (DCs [OLFM4]) and PBS (DCs [PBS]). DCs [P-OLFM4] inhibited tumor growth by 91.2 % and significantly reduced lung metastasis of OLFM4+ melanoma cells by 97 %, compared to the DCs [PBS]. DCs [OLFM4] also demonstrated a reduction in lung metastasis by 59.7 % compared to DCs [PBS]. Immunization with DCs [P-OLFM4] enhanced OLFM4-specific T-cell proliferation, interferon-γ production, and cytotoxic T cell activity in mice. The results indicate that OLFM4 is a viable target for CSC-focused immunotherapy. DC [P-OLFM4] vaccines can elicit robust immune responses, significantly inhibiting tumor growth and metastasis. This strategy holds promise for developing more effective cancer treatments that specifically target CSCs, potentially leading to better patient outcomes by reducing the likelihood of tumor relapse and metastasis.

Laparoscopic Extraperitoneal Approach for Lateral Pelvic Node Dissection in Rectal Cancer: Techniques and Short-Term Outcomes.

BACKGROUND: Lateral pelvic lymph node dissection has been performed selectively in rectal cancer cases; however, it involves highly skilled techniques because of the complex adjacent anatomical structures. MATERIALS AND METHODS: Laparoscopic EP-LPND was performed in Korea University Anam Hospital from June 2018, and short-term surgical outcomes were analyzed from June to December 2018. Among the patients with histologically diagnosed rectal adenocarcinoma, patients who were suspected Lateral pelvic lymph node metastasis at magnetic resonance imaging were selected for this procedure. RESULTS: Seven patients underwent laparoscopic extraperitoneal approach for lateral pelvic lymph node dissection in the study period. The mean number of retrieved lymph node was 4.57, and metastatic lymph nodes were identified in 3 patients (42.8%). All of the lymph nodes with suspected metastasis preoperatively were removed in postoperative images. There was no immediate postoperative complication beyond the moderate grade associated with lateral pelvic lymph node dissection. The median follow-up was 9 months, and there were no local recurrence nor complications related to sexual and voiding functions. CONCLUSIONS: The laparoscopic extraperitoneal approach might be an efficient way to perform lateral pelvic lymph node dissection using the same principles as the conventional method without violation of the peritoneum.

A Minimally Invasive Pelvic Multivisceral Resection Approach for Locally Advanced Primary Colorectal Cancers: A Single-Institution Experience.

Background: The role of minimally invasive surgery (MIS) in locally advanced colorectal cancers (CRCs) suspected of direct invasion to adjacent organs or structures remains controversial. The aim of this study is to verify the safety and feasibility of minimally invasive multivisceral resection (MVR) surgery for locally advanced CRCs compared with conventional open surgery. Materials and Methods: Prospectively collected data from patients who underwent MVR for locally advanced CRCs from 2007 to 2017 were retrospectively reviewed. Patients with preoperative clinically suspected T4b stage cancers were enrolled in the study. Results: There were 30 and 19 patients in the MIS and open surgery groups, respectively. Seven patients in the MIS group required conversion, and the most common reason for conversion was ureter and bladder invasion. Tumor sizes were significantly larger in the open group (5.46 cm versus 7.48 cm, P = .010), whereas the MIS group included more patients with rectal cancers (56.7% versus 21%, P = .021). No differences were observed between the two groups in terms of operation time, estimated blood loss, and postoperative hospital stay. Curative (R0) resection was achieved in all patients, and the median follow-up period was 23 months. The 3-year overall survival in the MIS group was 73.6% and 77.9% in the open group (P = .445), and the 3-year total disease-free survival (DFS) was 59.2% and 51.4%, respectively (P = .695). Three-year local DFS was 83.3% for the MIS group, and 51.4% for the open group (P = .120). Conclusion: MIS for primary T4b CRCs without urinary tract invasion is safe and feasible.

A survey investigating the current situation of the international visiting scholar program at the department of surgery in Korea.

PURPOSE: The number of international visiting scholars has been on the increase in Korea and we aim to investigate the program's current situation. METHODS: This cross-sectional study is based on an online survey questionnaire responded by international visiting scholars in surgical departments of 8 Korean hospitals between 2014 and 2018 about their experiences and satisfaction with the visiting scholar program. RESULTS: A total of 1,496 international scholars from 80 countries visited various surgical departments in 8 Korean hospitals between 2014 and 2018. The numbers have been on the increase over the years. Out of 355 visiting scholars in 2018, 71 replied to the online survey, of whom 52 were male and 19 female, and mostly in their 30s and 40s. Information about the program was accessed mostly through friends or colleagues (42.3%) and international conferences (36.6%). The commonest funding source was private (35.2%) and more than half stayed for less than 3 months. The visiting scholar's main roles were mostly observation or participation in surgery and clinical research. All but 1 were satisfied with the program (98.6%) and would recommend it to friends and colleagues, although the language barrier was identified as an inconvenience. Those aged 20-39 years with governmental or institutional funding were associated with stays of more than 1 year. CONCLUSION: The number of international visiting scholars at surgical departments in Korean hospitals has been on the increase with high satisfaction levels. Improvements need to be made on funding sources and lengthening visiting period to maximize the benefits of the program.

Minimally invasive complete mesocolic excision for right colon cancer.

Complete mesocolic excision (CME) with central vascular ligation (CVL) follows the same principles as the total mesorectal excision (TME) in the rectum of following the embryological planes for right-sided cancers. The number of lymph nodes yielded increased with a resultant improvement in the oncological outcomes and by reducing local recurrence rates. Hohenberger's radical CME and CVL and the East's modified CME with D3 lymphadenectomy, which traditionally followed the embryological plane dissection for most of its intraabdominal cancer resection, have both shown to harvest significantly higher number of lymph nodes leading to a higher overall survival rate than the traditional right hemicolectomies of the West. To achieve the oncologically superior excision of the CME, awareness of the significant vascular anatomical variation will enhance the precision of the oncosurgery as well as minimize the risk of vascular complications. There has been an increasing body of evidence emerging on the safety of minimally invasive surgery (MIS); both its oncological safety as well as complication rates in the hands of expert and trained surgeons. The surgical technique of a CME right hemicolectomy is described step by step to aid standardization. There is mounting evidence that CME + CVL/ D3 improves survival in patients with colon cancer. Whilst the technical aspect of MIS is more challenging than the left, with a standardized technique and systematic teaching method, safety and benefits for patients can be achieved.

miR-326-histone deacetylase-3 feedback loop regulates the invasion and tumorigenic and angiogenic response to anti-cancer drugs.

Histone modification is known to be associated with multidrug resistance phenotypes. Cancer cell lines that are resistant or have been made resistant to anti-cancer drugs showed lower expression levels of histone deacetylase-3 (HDAC3), among the histone deacetylase(s), than cancer cell lines that were sensitive to anti-cancer drugs. Celastrol and Taxol decreased the expression of HDAC3 in cancer cell lines sensitive to anti-cancer drugs. HDAC3 negatively regulated the invasion, migration, and anchorage-independent growth of cancer cells. HDAC3 conferred sensitivity to anti-cancer drugs in vitro and in vivo. TargetScan analysis predicted miR-326 as a negative regulator of HDAC3. ChIP assays and luciferase assays showed a negative feedback loop between HDAC3 and miR-326. miR-326 decreased the apoptotic effect of anti-cancer drugs, and the miR-326 inhibitor increased the apoptotic effect of anti-cancer drugs. miR-326 enhanced the invasion and migration potential of cancer cells. The miR-326 inhibitor negatively regulated the tumorigenic, metastatic, and angiogenic potential of anti-cancer drug-resistant cancer cells. HDAC3 showed a positive feedback loop with miRNAs such as miR-200b, miR-217, and miR-335. miR-200b, miR-217, and miR-335 negatively regulated the expression of miR-326 and the invasion and migration potential of cancer cells while enhancing the apoptotic effect of anti-cancer drugs. TargetScan analysis predicted miR-200b and miR-217 as negative regulators of cancer-associated gene, a cancer/testis antigen, which is known to regulate the response to anti-cancer drugs. HDAC3 and miR-326 acted upstream of the cancer-associated gene. Thus, we show that the miR-326-HDAC3 feedback loop can be employed as a target for the development of anti-cancer therapeutics.

HDAC3 acts as a negative regulator of angiogenesis.

Histone deacetylase-3 (HDAC3) is involved in cellular proliferation, apoptosis and transcriptional repression. However, the role of HDAC3 in angiogenesis remains unknown. HDAC3 negatively regulated the expression of angiogenic factors, such as VEGF and plasminogen activator inhibitor-1 (PAI-1). HDAC3 showed binding to promoter sequences of PAI-1. HDAC3 activity was necessary for the expression regulation of PAI-1 by HDAC3. VEGF decreased the expression of HDAC3, and the down-regulation of HDAC3 enhanced endothelial cell tube formation. HDAC3 negatively regulated tumor-induced angiogenic potential. We show the novel role of HDAC3 as a negative regulator of angiogenesis.

Nuclear localization signal domain of HDAC3 is necessary and sufficient for the expression regulation of MDR1.

Histone acetylation/deacetylation has been known to be associated with the transcriptional regulation of various genes. The role of histone deacetylase-3 in the expression regulation of MDR1 was investigated. The expression level of HDAC3 showed an inverse relationship with the expression level of MDR1. Wild-type HDAC3, but not catalytic mutant HDAC3(S424A), negatively regulated the expression of MDR1. Wild-type HDAC3, but not catalytic mutant HDAC3(S424A), showed binding to the promoter sequences of HDAC3. HDAC3 regulated the expression level, and the binding of Ac-H3(K9/14) and Ac-H4(K16) around the MDR1 promoter sequences. The nuclear localization signal domain of HDAC3 was necessary, and sufficient for the binding of HDAC3 to the MDR1 promoter sequences and for conferring sensitivity to microtubule-targeting drugs.

Integrin α(5) interacts with EGFR, is necessary for FcɛRI signaling and is necessary for allergic inflammation in relation with angiogenesis.

Recent reports have suggested role for epidermal growth factor receptor (EGFR) in asthma and skin inflammation. Integrin(s) are known to be necessary for the transactivation of EGFR. The roles of EGFR and integrin(s) in allergic inflammation were investigated. Antigen stimulation induced activation of EGFR and interaction between EGFR and integrin α(5) in Rat Basophilic Leukemia (RBL2H3) cells and bone marrow-derived mouse mast cells (BMMCs). Flow cytometry revealed increased phosphorylation of EGFR on cell surfaces. Antigen stimulation induced interaction between EGFR and FcɛRI in both RBL2H3 cells and BMMCs. Blocking of EGFR or integrin α exerted negative effects on rac1 activity and secretion of ß-hexosaminidase in both RBL2H3 cells and BMMCs. EGFR and integrin α(5) were found to be necessary for IgE-dependent cutaneous anaphylaxis. FAK (focal adhesion kinase), interacted with EGFR and with FcɛRI upon antigen stimulation, and it was necessary for the increased secretion of ß-hexosaminidase in both RBL2H3 cells and BMMCs. EGFR and integrin α(5) were necessary for interactions between activated RBL2H3 cells, BMMCs and rat aortic endothelial cells (RAECs). Conditioned medium of antigen-stimulated RBL2H3 cells promoted RAECs tube formation, rat aortic ring formation and blood vessel formation. Conditioned medium of antigen-stimulated BMMCs also had the same effects on RAECs. This enhanced angiogenic potential of RAECs was dependent on EGFR and integrin α(5). In conclusion, EGFR, via interaction with FcɛRI and integrin α(5), is necessary for allergic inflammation associated with cellular interaction.

Cancer/testis antigen CAGE exerts negative regulation on p53 expression through HDAC2 and confers resistance to anti-cancer drugs.

The role of the cancer/testis antigen CAGE in drug resistance was investigated. The drug-resistant human melanoma Malme3M (Malme3M(R)) and the human hepatic cancer cell line SNU387 (SNU387(R)) showed in vivo drug resistance and CAGE induction. Induction of CAGE resulted from decreased expression and thereby displacement of DNA methyltransferase 1(DNMT1) from CAGE promoter sequences. Various drugs induce expression of CAGE by decreasing expression of DNMT1, and hypomethylation of CAGE was correlated with the increased expression of CAGE. Down-regulation of CAGE in these cell lines decreased invasion and enhanced drug sensitivity resulting from increased apoptosis. Down-regulation of CAGE also led to decreased anchorage-independent growth. Down-regulation of CAGE led to increased expression of p53, suggesting that CAGE may act as a negative regulator of p53. Down-regulation of p53 enhanced resistance to drugs and prevented drugs from exerting apoptotic effects. In SNU387(R) cells, CAGE induced the interaction between histone deacetylase 2 (HDAC2) and Snail, which exerted a negative effect on p53 expression. Chromatin immunoprecipitation assay showed that CAGE, through interaction with HDAC2, exerted a negative effect on p53 expression in Malme3M(R) cells. These results suggest that CAGE confers drug resistance by regulating expression of p53 through HDAC2. Taken together, these results show the potential value of CAGE as a target for the development of cancer therapeutics.

CAGE, a cancer/testis antigen, induces c-FLIP(L) and Snail to enhance cell motility and increase resistance to an anti-cancer drug.

Cancer associated gene (CAGE) regulates expression of epithelial-mesenchymal transition (EMT)-related proteins through extracellular regulated kinase (ERK), Akt and nuclear factor kappaB (NF-kB) in mouse B16F10 melanoma cells. Snail, a EMT-related protein, mediates the effect of CAGE on the induction of matrix metalloproteinase-2 (MMP-2) and cancer cell motility. C-Flice inhibitory protein mediates the effect of CAGE on the induction of MMP-2 and cell motility by the induction of Snail. CAGE was shown to protect cells against celastrol, an anti-cancer agent. Celastrol-resistant B16F10 melanoma cells had a higher expression level of c-FLIP(L) and Snail as compared with a sensitive cell line.

Multiplex targeting, tracking, and imaging of apoptosis by fluorescent surface enhanced Raman spectroscopic dots.

We have developed multifunctional fluorescent surface enhanced Raman spectroscopic tagging material (F-SERS dots) composed of silver nanoparticle-embedded silica spheres with fluorescent organic dye and specific Raman labels for multiplex targeting, tracking, and imaging of cellular/molecular events in the living organism. In this study, F-SERS dots fabricated with specific target antibodies (BAX and BAD) were employed for the detection of apoptosis. The F-SERS dots did not show any particular toxicity in several cell lines. The F-SERS dots could monitor the apoptosis effectively and simultaneously through fluorescent images as well as Raman signals in both cells and tissues with high selectivity. Our results clearly demonstrate that F-SERS dots can be easily applicable to multiplex analysis of diverse cellular/molecular events important for maintaining cellular homeostasis.