Survival improvements of marine mammals in zoological institutions mirror historical advances in human longevity.

An intense public debate has fuelled governmental bans on marine mammals held in zoological institutions. The debate rests on the assumption that survival in zoological institutions has been and remains lower than in the wild, albeit the scientific evidence in support of this notion is equivocal. Here, we used statistical methods previously applied to assess historical improvements in human lifespan and data on 8864 individuals of four marine mammal species (harbour seal, Phoca vitulina; California sea lion, Zalophus californianus; polar bear, Ursus maritimus; common bottlenose dolphin, Tursiops truncatus) held in zoos from 1829 to 2020. We found that life expectancy increased up to 3.40 times, and first-year mortality declined up to 31%, during the last century in zoos. Moreover, the life expectancy of animals in zoos is currently 1.65-3.55 times longer than their wild counterparts. Like humans, these improvements have occurred concurrently with advances in management practices, crucial for population welfare. Science-based decisions will help effective legislative changes and ensure better implementation of animal care.

Ulnar neuropathy at the elbow in 413 Japanese patients: An assessment of pathological elbow lesions and neurological severity.

BACKGROUND: Various pathological elbow lesions are often complicated with ulnar neuropathy at the elbow (UNE), although the precise pathology, incidence, and clinical and neurological features of these lesions have not been identified. We therefore investigated elbow pathology and neurological severity in Japanese patients with UNE. METHODS: The medical records of 457 Japanese UNE patients who were surgically treated among 6 hospitals were retrospectively examined. Eligible patients had UNE diagnosed by physical findings and nerve conduction studies according to the criteria of the American Association of Electrodiagnostic Medicine. The elbows were analyzed with regard to age, gender, occupation, pathology at the elbow, and severity of nerve palsy. RESULTS: A total of 398 patients with 413 UNE elbows of a mean age of 63 years (range: 15-87) met the inclusion criteria. UNE elbows were predominantly in male patients (69.0%). Overall, 310 elbows (75.1%) had 1 or more elbow lesions: 238 elbows (76.8%) had a single lesion and 72 elbows (23.3%) had 2 or more lesions. The most common lesion was primary elbow osteoarthritis (EOA) occurring in 54.5% of elbows, followed next by medial elbow ganglion in 8.5% and cubitus valgus in 6.5%. Most elbows with medial elbow ganglion or cubitus valgus were associated with EOA. Entrapment sites were at the cubital tunnel in 84.5%-91.3% of UNE elbows, regardless of an association with elbow lesion. The incidence of McGowan grade III lesion was 50.8% in elbows with primary EOA, which was higher than the 35.0% in elbows with no lesion. CONCLUSIONS: This study revealed that UNE had various isolated or combined elbow lesions. In Japanese UNE, primary or secondary EOA was found in 62.2% of cases and severe motor weakness was noted in 47.2%. The incidences of EOA and severe ulnar nerve palsy in the Japanese UNE are higher than those in Caucasians. LEVEL OF EVIDENCE: Level IV; Prognostic-Investigating the effect of a patient characteristic on the outcome of a disease; Case series.

[A Case of Long-Term Survival after Chemotherapy and Ablation Therapy Using Various Approaches for Multiple Colon Cancer Liver Metastases].

A 58-year-old man with unresectable sigmoid colon cancer and multiple liver metastases(H2, more than 30)received chemotherapy for 2 years. Subsequently, the patient was diagnosed with stenosis of the primary lesion and 5 bilobar, metastatic tumors. Simultaneous resection was unsuitable because of the performance status and comorbidities of the patient. The first surgery consisted of laparoscopic-assisted sigmoidectomy, laparoscopic microwave coagulation therapy(MCT), and percutaneous radiofrequency ablation(RFA). Percutaneous RFA was additionally performed after 2 months. Since 2 liver metastases(S3 and S8)were inadequately treated, 3 courses of P-mab plus FOLFIRI were administered. Finally, laparoscopic- assisted RFA was performed. Subsequently, serum CEA reduced from 288.3 ng/mL to the normal level. We used fusion imaging US, sonazoid US, laparoscopic convex probe, and ICG fluorescence imaging for ablation therapy. Chemotherapy and ablation therapy using various approaches can control unresectable multiple liver metastases and prolong survival by more than 3 years.

[A Patient with Multiple Colorectal Liver Metastases for Whom Partial Splenic Embolization Contributed Extremely to Maintain Multidisciplinary Treatment].

After approximately 2.5 years of chemotherapy at the referred hospital, a 69-year-old man with double colon cancer and unresectable liver metastases(H3)sought consultation. A total of 8 liver metastases were deemed resectable; however, the disease was progressive. He received 2 courses of mFOLFOX6 plus Bmab before hepatectomy. Seven weeks after starting chemotherapy, Grade 4 thrombocytopenia occurred, which required platelet transfusion. Ten weeks after, curative parenchymal- preserving hepatectomy was performed under platelet transfusion. Hematologic examination including bone marrow aspiration showed no significant abnormalities, including normal megakaryocyte formation. Therefore, the patient was diagnosed with thrombocytopenia due to sinusoidal obstruction syndrome associated with past chemotherapy including oxaliplatin. Partial splenic embolization(PSE)was performed 8 weeks after the first hepatectomy. The infarcted splenic ratio was 79.5%, and the infarcted splenic volume was 444.3 mL. Curative resection of the primary colorectal cancer and the 2nd hepatectomy for the newly developed recurrent liver lesions was successfully performed at 2 weeks and 19 weeks after PSE, respectively. Platelet transfusion was never required in the perioperative period of the 2 operations performed after the PSE. Forty-five months after the initial treatment, the patient is alive with no recurrent tumors and normal tumor marker levels.

[A Case of Advanced Transverse Colon Cancer with Nephrotic Syndrome Treated with Curative Resection and Complete Adjuvant Chemotherapy].

A 74-year-old woman was diagnosed as having transverse colon cancer after diagnosis of nephrotic syndrome caused by membranous nephropathy. Although she had hypoproteinemia and hypoalbuminemia, we judged that she had no major nutritional problem. In previous, similar case reports, the use of human serum albumin and fresh-frozen plasma was suggested to be important to avoid complications in the perioperative period. Thus, we used the same in our patient in the perioperative period. In addition, we paid special attention to perioperative nutrition management and used total parenteral nutrition in perioperative period. We performed laparoscopic assisted right hemicolectomy. On the 15th day after the surgical resection, the patient was discharged without any problems. We considered that postoperative adjuvant chemotherapy with XELOX (CapeOX)should be performed because the TNM pathological stage was pStage III b. Regarding adjuvant chemotherapy for gastrointestinal cancer with nephrotic syndrome, no previous reports detailed the indications for postoperative adjuvant chemotherapy. Upon introduction of adjuvant chemotherapy, we determined adaptation in accordance with the general adaptation criteria. While observing the patient's progress with a nephrologist, we safely completed the scheduled 8 courses adjuvant chemotherapy.

Stretchable, adhesive and ultra-conformable elastomer thin films.

Thermoplastic elastomers are attractive materials because of the drastic changes in their physical properties above and below the glass transition temperature (Tg). In this paper, we report that free-standing polystyrene (PS, Tg: 100 °C) and polystyrene-polybutadiene-polystyrene triblock copolymer (SBS, Tg: -70 °C) thin films with a thickness of hundreds of nanometers were prepared by a gravure coating method. Among the mechanical properties of these thin films determined by bulge testing and tensile testing, the SBS thin films exhibited a much lower elastic modulus (ca. 0.045 GPa, 212 nm thickness) in comparison with the PS thin films (ca. 1.19 GPa, 217 nm thickness). The lower elastic modulus and lower thickness of the SBS thin films resulted in higher conformability and thus higher strength of adhesion to an uneven surface such as an artificial skin model with roughness (Ra = 10.6 µm), even though they both have similar surface energies. By analyzing the mechanical properties of the SBS thin films, the elastic modulus and thickness of the thin films were strongly correlated with their conformability to a rough surface, which thus led to a high adhesive strength. Therefore, the SBS thin films will be useful as coating layers for a variety of materials.

The effect of vascular pedicle preservation on blood flow and clinical outcome following ulnar nerve transposition.

PURPOSE: To evaluate the efficacy of a technique to preserve the extrinsic vascular supply to the ulnar nerve after transposition and its effect on blood flow and clinical outcome. METHODS: We included 36 patients with cubital tunnel syndrome. The patients were randomly selected to undergo vascular pedicles-sparing surgery for anterior ulnar nerve transposition (VP group) or nerve transposition and artery ligation (non-VP group). Blood flow to the ulnar nerve was estimated intraoperatively at 3 locations in the cubital tunnel before and after transposition using a laser Doppler flowmeter. Clinical results at 3, 6, and 12 months after surgery were also compared between the 2 groups. RESULTS: The blood flow before ulnar nerve transposition was not significantly different between the groups. Blood flow at all 3 locations after the ulnar nerve transposition was significantly higher in the VP group than in the non-VP group. Blood flow in the non-VP group reduced to values between 28% and 52% from the pre-transposition baseline values. After surgery, no significant differences were observed in the clinical results between the groups, except for the Disabilities of the Arm, Shoulder and Hand scores at 12 months after surgery, which was greater in the non-VP group. CONCLUSIONS: The procedure of preserving the extrinsic vascular pedicles can prevent compromise of blood flow to the ulnar nerve immediately after nerve transposition. However, this procedure had no correlation to improved recovery of ulnar nerve function after surgery. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic II.

Chronic dislocations of the fourth and fifth carpometacarpal joints with successful treatment by ligament repair: A case report and literature review.

Dislocations of the fourth and fifth carpometacarpal joints (CMCJs) are rare and often misdiagnosed via radiography. Moreover, treatment strategies have not yet been standardized. Herein, we report a case of chronic dislocations of the fourth and fifth CMCJs with delayed diagnosis and successful treatment via ligament repair. A 29-year-old male patient who was initially diagnosed with contusion at another center following a fall on the stairs was referred to our hospital one month later due to persistent pain and swelling. Fourth and fifth CMCJ dislocations were diagnosed using radiography and computed tomography. Closed reduction attempts were unsuccessful, prompting open reduction. The operative findings included rupture of the dorsal carpometacarpal ligament and hamate cartilage injury. Using two mini anchors, the fourth and fifth dorsal carpometacarpal ligaments were repaired, and Kirschner-wire (K-wire) pinning was performed. The K-wire was extracted after four weeks. At the eight-month follow-up, the only remaining symptom was mild discomfort, and the range of motion and grip strength was fully recovered. Our findings highlight the difficulties in diagnosing CMCJ dislocation and suggest ligament repair as a treatment option for chronic cases of CMCJ dislocation.

Chemotherapy with bevacizumab for metastatic colorectal cancer: a retrospective review of 181 Japanese patients.

BACKGROUND: There has so far been little information on the clinical effect of bevacizumab against colorectal cancer in Japan. Hence, this study was conducted to retrospectively evaluate the safety and efficacy of bevacizumab in clinical practice. METHODS: A total of 181 patients with metastatic colorectal cancer (mCRC) received bevacizumab in combination with chemotherapy at 18 hospitals in Kumamoto prefecture, Japan. We surveyed the medical records of all patients regarding the patient characteristics, objective tumor responses, and adverse events. We analyzed their overall survival and the survival benefit when continuing the administration of bevacizumab beyond disease progression (progressive disease; PD) in patients who received bevacizumab-containing 1st line therapy. RESULTS: The response rate (RR) in all lines of therapy was 42 %. The 1st line patients showed significantly better survival in comparison to the patients who received further lines of treatment (P = 0.005). There were no significant differences in survival between the group with post-PD treatment with bevacizumab and the group with post-PD treatment without bevacizumab (P = 0.13). The most common grade 3 or greater adverse event associated with bevacizumab was hypertension (12.2 %). Especially, a high incidence of gastrointestinal (GI) perforation was shown in this study (4.4 %) and most of the patients with GI perforation had some risk factors for this complication. CONCLUSION: Although the survival benefit of bevacizumab in Japanese patients with mCRC was similar to that observed in previous clinical trials, this study showed a high incidence of GI perforation in comparison to previous studies. Therefore, the careful selection of patients with few risk factors for this complication is likely to lead to a greater benefit from bevacizumab treatment.

Usefulness of transcription-reverse transcription concerted reaction method for detecting circulating tumor cells in patients with colorectal cancer.

PURPOSE: The CellSearch system (Veridex, LLC) is useful for detecting circulating tumor cells (CTCs) in various carcinomas, including colorectal cancer (CRC); however, there are some problems associated with its clinical use. A transcription-reverse transcription concerted reaction (TRC) method, which is a PCR-based technique producing more stable and reliable results, because it is a more simplified process compared with the conventional techniques, has been introduced for detecting micrometastasis in some carcinomas. We aimed to demonstrate the effectiveness of TRC method in the CTC detection. METHODS: We compared the two methods for the sensitivity for CTC detection using the colon cancer cell line and 42 whole-blood samples from patients with advanced or metastatic CRC. Furthermore, 25 patients with metastatic CRC were enrolled to investigate the correlation between CTC detection and prognosis in both methods. RESULTS: The sensitivity of the TRC method was similar to that of the CellSearch system. The overall survival rate was significantly worse in the patients diagnosed as CTC-positive by the TRC method than in those diagnosed as CTC-negative; this finding was similar to the prognosis indicated by the CellSearch system. However, clinically, the TRC method could detect CTCs more rapidly and at a reduced cost compared with the CellSearch system. CONCLUSIONS: The TRC method seems to be a useful alternative to the CellSearch system for clinically detecting CTCs in patients with metastatic CRC.

Induction chemotherapy with docetaxel/cisplatin/5-fluorouracil for patients with node-positive esophageal cancer.

BACKGROUND: Despite improvements in the surgical management of esophageal cancer, the prognosis of patients with lymph node metastases is still unsatisfactory. Recently, survival benefit of neoadjuvant or induction chemotherapy for patients with esophageal cancer has been highlighted. METHODS: Efficacy and toxicity of induction chemotherapy for esophageal cancer were reviewed. In addition, our experience on modified docetaxel/cisplatin/5-FU (DCF) as induction chemotherapy was also demonstrated. The modified DCF consisted of 60 mg/m² of docetaxel on day 1, and 350 mg/m² of 5-FU and 6 mg/m² of cisplatin on days 1-5. Two courses have been administered as induction chemotherapy in 51 patients with node-positive esophageal cancer. Response was evaluated by RECIST v1.0 and changes in standardized uptake value by ¹8F-fluorodeoxyglucose positron emission tomography. RESULTS: Induction chemotherapy may be beneficial for node-positive esophageal cancer, although the consensus has not yet been established. A regimen of induction chemotherapy should have a high response rate and cisplatin/5-FU may be underpowered as an induction setting. DCF can be a candidate for the regimen of induction chemotherapy for esophageal cancer, although severe adverse events have been reported. Several modified regimens to reduce the toxicity have been reported. The response rate of our series was 61% and a significant decrease in standardized uptake values was observed after the induction chemotherapy. Although high-grade neutropenia was still observed with this regimen, neither treatment-related death nor delay in the following treatment was observed. CONCLUSIONS: Modified DCF can be a regimen of induction chemotherapy for node-positive esophageal cancer because of its high efficacy, although an adequate care for severe neutropenia is needed.

Surgical reconstruction using suture anchor for dislocation of the carpometacarpal joint of the thumb: a case report.

Dislocation of the carpometacarpal joint of the thumb is a rare injury. This is the first report in the literature performing ligamentous reconstruction using suture anchors in a case of severe joint instability after manipulative reduction for dislocation of the first carpometacarpal joint. Our surgical procedure successfully resulted in a stable pain-free thumb 1 year postoperatively.

Hepatic Inflammatory Pseudotumor Mimicking Malignant Tumor With Rare Onset of Intra-abdominal Hemorrhage.

BACKGROUND: Hepatic inflammatory pseudotumor (HIPT) is an uncommon benign tumor-like mass that mimics malignant tumors. CASE REPORT: A 73-year-old man was admitted with severe epigastric pain and high fever. He had received choledocojejunostomy. Enhanced computed tomography showed a 76 mm, heterogeneous, gradual enhanced low-density mass in the caudate lobe and hyperdense fluid was detected around the mass. Based on the diagnosis of hemorrhage from a hypervascular malignant liver tumor, chemoembolization was conducted. Antibiotics (Meropenem) were administered for 2 weeks, and methylprednisolone (125 mg) was administered twice as a premedication for chemoembolization. After the 2nd chemoembolization, rapid tumor shrinkage was observed and the inflammatory changes gradually disappeared. The tumor was finally diagnosed as fibrohistiocytic type HIPT with an ultrasound-guided percutaneous tumor biopsy. The diameter of the liver tumor decreased to 15 mm and intra-abdominal hemorrhage disappeared in 3 months. CONCLUSION: Development of HIPT can be associated with intra-abdominal hemorrhage.

A Case Report of Metachronous Multiple Adenosquamous Carcinoma of the Colon Over-expressing PD-L1 and a Literature Review.

BACKGROUND: Colorectal cancer is the third most commonly diagnosed cancer in both men and women, and one of the more widely recognized preventable cancers. Adenosquamous carcinoma (ASC) of the colon/rectum is an uncommon disease that consists of both glandular and squamous components, and the most common site of ACS is the right and transverse colon. CASE REPORT: Here, we present the case of a 78-year-old woman, who complained of abdominal pain. Colonoscopy revealed a circumscribed tumor in the ascending colon, and no specific lesion was detected in the other areas of the colon or rectum. ASC (pT3N0M0) was diagnosed from right hemicolectomy specimens. Three months after the first surgery, the serum levels of tumor markers had gradually increased, and a new tumor was subsequently detected in the sigmoid colon 2 months later. The sigmoid lesion was surgically resected and diagnosed as ASC (pT3N3M0). Strong PD-L1 expression was also found in the squamous component. CONCLUSION: To our knowledge, this is the first report of a recurrent sigmoid colon ASC that likely originated from the ascending colon, and PD-L1/PD-1 signaling was likely involved in the immune escape mechanism.

Huge hepatocellular carcinoma with extrahepatic collateral arteries successfully treated by multidisciplinary treatment including laparoscopic devascularization: a case report.

Multidisciplinary treatment is recommended for the management of patients with advanced hepatocellular carcinoma (HCC). Some operative decollateralization of extrahepatic feeding arteries with laparotomy have been introduced for HCC. We herein newly develop laparoscopic devascularization (LDEV) to continue transarterial chemoembolization (TACE) for HCC with extrahepatic collateral arteries. A 74-year-old man with multiple huge HCC (4 tumors, 18 cm in diameter) and poor liver function (non-alcoholic steatohepatitis, Child-Pugh score 7) was treated with 6 times of chemoembolization in combination with LDEV, 3 times of ablation therapies, and lenvatinib therapy. His tumor markers were triple positive (AFP, 12,906.5 ng/ml; PIVKA-II, 491,743 mAU/ml; AFP-L3, 91.8%) before treatments; however, they all returned to normal limits. Complete response was achieved according to the modified RECIST criteria. Unfortunately, he died 6 months after the final treatment with no recurrence of HCC due to the postoperative complication of primary lung cancer. LDEV is a useful tool to continue effective TACE, and multidisciplinary treatment including chemoembolization and LDEV can cure advanced HCC patients with extrahepatic collaterals and impaired liver function.

Mobility of the forearm skeleton in the Asiatic black (Ursus thibetanus), brown (U. arctos) and polar (U. maritimus) bears.

In several primates and carnivores, pronation/supination angles of the forearm skeleton were examined, and it is thought that a larger angle is useful to acquire dexterous behaviors in feeding and/or life style, including climbing. In this study, the pronation/supination angles in Asiatic black, brown and polar bears were nondestructively examined. These specimens were classified as adult or non-adult. Three or four carcasses of each group of Asiatic black and brown bears were used for CT analysis, whereas only one adult polar bear was used. The forearms were positioned within the gantry of a CT scanner in both maximally supinated and pronated states. Extracted cross-sectional CT images of two positions were superimposed by overlapping the outlines of each ulna. The centroids of the radii were detected, and then the centroid of each radius and the midpoint of a line which connects between both ends of the surface of each radius facing the ulna, were connected by lines to measure the angle of rotation as an index of pronation/supination. In adult brown and polar bears, the angles were smaller as compared with the other groups (Asiatic black and non-adult brown bears). Asiatic black and non-adult brown bears can climb trees, whereas adult brown bears and polar bears cannot. This suggests that the pronation/supination angle is related to arboreal activity in Ursidae.

Adenoviral oncolytic suicide gene therapy for a peritoneal dissemination model of gastric cancer in mice.

BACKGROUND: Peritoneal dissemination of gastric cancer is often refractory to systemic therapies. Although adenoviral gene therapy has been reported to be a potentially useful therapeutic modality, the adenovirus itself has a dose-limiting toxicity. A novel system was constructed using adenoviral oncolytic suicide gene therapy targeting carcinoembryonic antigen (CEA), and its therapeutic effect and the possibility to reduce the total viral dose while still preserving the antitumor effect were assessed. METHODS: Three types of adenoviruses were prepared for this novel system: (A) Ad/CEA-Cre, (B) Ad/lox-CD::UPRT for a Cre/loxP system, and (C) Ad/CEA-E1 for conditionally replicating adenovirus. The antitumor effect of the oncolytic suicide gene therapy (A + B + C) was then evaluated in vitro. Mice bearing peritoneal dissemination of human gastric cancer were treated with either this system (A + B + C) or with a tenfold viral dose of suicide gene therapy (A + B). The adverse effects in terms of hepatotoxicity were then evaluated between the two groups. RESULTS: The current system (A + B + C) demonstrated significantly better cytotoxic effect for CEA-producing cell lines than did suicide gene therapy (A + B) at the same viral dose in vitro. The effect of oncolytic suicide gene therapy was almost equal to that of the tenfold viral dose of suicide gene therapy in vivo. The hepatotoxicity of the two treated groups was also found to be equivalent. CONCLUSION: It was possible to reduce the total adenoviral dose of oncolytic suicide gene therapy while still preserving the antitumor effect.

Phosphorylated mTOR expression is associated with poor prognosis for patients with esophageal squamous cell carcinoma.

BACKGROUND: The mammalian target of rapamycin (mTOR) plays central roles in the regulation of cell growth and proliferation by monitoring nutrient availability, cellular energy level, oxygen level, and mitogenic signals. The aberrant activation of mTOR in relation to clinical outcome has been reported in several types of cancers. mTOR is increasingly important as a potential target for anticancer therapy. Nonetheless, a prognostic feature of mTOR activation in esophageal squamous cell carcinoma (ESCC) remains uncertain. MATERIALS AND METHODS: First, in order to validate phospho-specific mTOR antibody (Ser2448), phosphorylated mTOR (p-mTOR) expression levels in five ESCC cell lines under cultural conditions with or without everolimus (mTOR inhibitor, also known as RAD001) were evaluated by in vitro immunohistochemistry and immunoblotting. Second, we examined p-mTOR expression by immunohistochemistry using 143 resected ESCC specimens. Prognostic significance of p-mTOR expression was examined by Cox regression and Kaplan-Meier analyses. RESULTS: Among 143 patients, 71 (49.7%) were classified into p-mTOR-positive and 72 (50.3%) were classified into p-mTOR-negative. Compared with p-mTOR-negative patients, p-mTOR-positive patients experienced high overall mortality [hazard ratio (HR) 2.44; 95% confidence interval (CI), 1.24-4.83; P = 0.008], which persisted in multivariate analysis (multivariate HR 2.92; 95% CI, 1.48-5.78; P = 0.002). A similar finding was observed for esophageal cancer-specific mortality. p-mTOR expression was not related with any clinical or pathologic variables including age, sex, tumor location, histological grading, operative procedure, T classification (tumor invasion), or lymph-node metastasis. CONCLUSIONS: p-mTOR overexpression was independently associated with poor prognosis in ESCC, supporting the potential for mTOR as a therapeutic target for ESCC.

Extensive lymphatic spread of cancer cells in patients with thoracic esophageal squamous cell carcinoma: detection of CEA-mRNA in the three-field lymph nodes.

BACKGROUND AND OBJECTIVES: The aim of this study is to clarify the extent of lymphatic spread of cancer cells using a novel genetic test to examine patients with thoracic esophageal squamous cell carcinoma (ESCC). METHODS: A total of 35 patients who underwent an esophagectomy with three-field lymph node (LN) dissection were eligible. The regional LN stations were categorized into the cervical (C), recurrent nerve (RN), paraesophageal (PE), tracheo-bronchial (TB), and perigastric (PG) nodes. Lymphatic spread was pathologically diagnosed with Hematoxylin-Eosin (HE) and anti-cytokeratin immunohistochemistry (IHC) staining, and CEA-mRNA expression was examined using the transcription-reverse transcription concerted (TRC) reaction. RESULTS: The rates of lymphatic spread with HE, IHC, and TRC were 7.2%, 10.1%, and 55.5%, respectively. The number of CEA-mRNA(+) LN stations significantly correlated with tumor depth, LN metastasis diagnosed by HE, and vascular invasions. CEA-mRNA expression was observed in 42.9%, 94.3%, 77.1%, 80.0%, and 82.9% of C, RN, TB, PE, and PG nodes, respectively. CONCLUSIONS: The high frequency of CEA-mRNA expression suggests that systemic therapy is necessary in addition to esophagectomy with adequate LN dissection. Conversely, a relatively low frequency of CEA-mRNA expression in the C node does not support the routine dissection of the LNs in this area.

MicroRNA-21 regulates the proliferation and invasion in esophageal squamous cell carcinoma.

PURPOSE: MicroRNAs are approximately 22 nucleotide noncoding RNA molecules that posttranscriptionally regulate gene expression. The aim of this study was (a) to determine a role of microRNA-21 in esophageal squamous cell carcinoma and (b) to elucidate the regulation of the programmed cell death 4 (PDCD4) gene by microRNA-21. EXPERIMENTAL DESIGN: MicroRNA-21 expression was investigated in 20 matched normal esophageal epitheliums and esophageal squamous cell carcinomas and seven esophageal squamous cell carcinoma cell lines (TE6, TE8, TE10, TE11, TE12, TE14, KYSE30) by TaqMan quantitative real-time PCR and in situ hybridization. To evaluate the role of microRNA-21, cell proliferation and invasion were analyzed with anti-microRNA-21-transfected cells. In addition, the regulation of PDCD4 by microRNA-21 was elucidated to identify the mechanisms of this regulation. RESULTS: Of 20 paired samples, 18 cancer tissues overexpressed microRNA-21 in comparison with matched normal epitheliums. Specifically, patients with lymph node metastasis or venous invasion showed significantly high expression of microRNA-21. In situ hybridization for microRNA-21 showed strong positive staining in paraffin-embedded esophageal squamous cell carcinoma tissues. All seven esophageal squamous cell carcinoma cell lines also overexpressed microRNA-21, and anti-microRNA-21-transfected cells showed significant reduction in cellular proliferation and invasion. The PDCD4 protein levels in esophageal squamous cell carcinoma cells have an inverse correlation with microRNA-21 expression. Anti-microRNA-21-transfected cells increased PDCD4 protein expression without changing the PDCD4 mRNA level and increased a luciferase-reporter activity containing the PDCD4-3' untranslated region construct. CONCLUSIONS: MicroRNA-21 targets PDCD4 at the posttranscriptional level and regulates cell proliferation and invasion in esophageal squamous cell carcinoma. It may serve as a novel therapeutic target in esophageal squamous cell carcinoma.