Predictive factors associated with technical difficulty in colorectal endoscopic submucosal dissection: A Honam Association for the Study of Intestinal Disease (HASID) multicenter study.

Colorectal endoscopic submucosal dissection (ESD) is a promising but challenging procedure. It is not widely performed due to its technical difficulty. We aimed to find the predictive factors associated with technical difficulty in colorectal ESD before the procedure. Clinical data from patients who underwent ESD for colorectal tumors in 5 hospitals in Honam province of South Korea between 2015 and 2020 were reviewed retrospectively. Technically difficult colorectal ESD procedure was defined in 3 points. Long procedure time (longer than 60 minutes), occurrence of perforation, and failure of en bloc resection. Factors associated with technically difficult ESD were included as main outcome measure. 1446 patients were identified and their data were analyzed. Median procedure time was 30.0 minutes and median long axis of the tumor was 20.1 mm. Technically difficult procedures including long procedure time were 231 cases (16.0%), perforation occurred in 34 cases (2.3%), and en bloc resection was done in 1292 cases (89.3%). Tumor size larger than 35 mm (odd ratio [OR]: 1.474, P = .047), central depression or ulceration in the lesion (OR: 1.474, P = .013), previous endoscopic mucosal resection (EMR) or polypectomy procedure (OR: 2.428, P = .020) were associated with technically difficult ESD. Descending colon-located tumor (OR: 5.355, P < .001), and use of IT knife (OR: 4.157, P = .003) were associated with perforation. Recognizing factors associated with technically difficult ESD can help in planning the ESD procedure beforehand.

Outcomes of Colorectal Endoscopic Submucosal Dissection for Elderly Patients: A Multicenter Study by the Honam Association for the Study of Intestinal Disease (HASID).

BACKGROUND/AIM: The aging population has been growing gradually; therefore, the proportion of elderly patients undergoing colorectal endoscopic submucosal dissection (ESD) has also been increasing. However, there is a lack of large-scale studies on the efficacy and safety of colorectal ESD in elderly patients. PATIENTS AND METHODS: This retrospective analysis evaluated colorectal ESDs performed at five tertiary medical institutions between January 2015 and December 2020. Patients were categorized into the following four age groups: Middle-aged (<65 years), young-elderly (≥65 to <75 years), mid-elderly (≥75 to <85 years), and very elderly (≥85 years). Of the 1,446 patients included, 668 (46.2%), 466 (32.2%), 293 (20.3%), and 19 (1.3%) were in the middle-aged, young-elderly, mid-elderly, and very-elderly groups, respectively. RESULTS: Compared to younger patients, more older patients used aspirin, clopidogrel, and anti-thrombotic agents. Additionally, the Charlson comorbidity index increased significantly with increasing age. However, no significant differences were observed in the complete resection rates nor the rates of complications, such as perforation, bleeding, and post-ESD coagulation syndrome, among the different age groups. A restricted cubic spline curve was used to construct predictive models for complete resection and major complications based on age and showed that the need for complete resection did not decrease with increasing age. Furthermore, major complications did not significantly differ with age progression. CONCLUSION: Colorectal ESD should be actively considered as a relatively safe and effective treatment method for elderly patients.

Cytochrome P450 Family 46 Subfamily A Member 1 Promotes the Progression of Colorectal Cancer by Inducing Tumor Cell Proliferation and Angiogenesis.

BACKGROUND/AIM: Cytochrome P450 family 46 subfamily A member 1 (CYP46A1) has been implicated in the development and progression of various cancers. This study aimed to analyze the expression of CYP46A1, examining its relationship with oncogenic behaviors, and determining its prognostic implications in colorectal cancer (CRC). MATERIALS AND METHODS: A total of 225 patients with CRC who underwent curative surgical resection were examined using paraffin-embedded tissue blocks and subjected to tumor-specific survival analysis. The expression of CYP46A1 was assessed in CRC tissues through reverse transcription-polymerase chain reaction, western blotting, and immunohistochemistry. The CRC cells' apoptosis, proliferation, angiogenesis, and lymphangiogenesis were analyzed using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assays, alongside immunohistochemical staining for Ki-67, CD34, and D2-40 antibodies. RESULTS: CYP46A1 expression was found to be up-regulated in CRC tissues compared to normal colorectal mucosa. Such expression was significantly associated with advanced stage, deeper tumor invasion, lymph node metastasis, distant metastasis, and decreased survival. Furthermore, the mean Ki-67 labeling index and microvessel density values in CYP46A1-positive tumors were significantly elevated compared to CYP46A1-negative tumors. However, there was no discernible correlation between CYP46A1 expression and either the apoptotic index or lymphatic vessel density value. CONCLUSION: CYP46A1 promotes CRC progression, specifically through the induction of tumor cell proliferation and angiogenesis. The insights provided may hold potential implications for future therapeutic interventions targeting CYP46A1.

Effectiveness and Safety of Endoscopic Submucosal Dissection for Colorectal Neoplasm in Patients with High Charlson Comorbidity Index Score: A HASID Multicenter Study.

Endoscopic submucosal dissection (ESD) is an effective method for removing early colorectal lesions. However, research on the safety and efficacy of ESD in patients with various underlying conditions remains limited. This study retrospectively examined ESD outcomes in colorectal neoplasm patients from five tertiary medical centers. The Charlson Comorbidity Index (CCI) and age-adjusted CCI (ACCI) were analyzed, and the differences in complete resection and complication rates were analyzed. The CCI, ACCI, and complication rates tended to gradually increase proportionally, and the complication resection rate increased from CCI 2 to ACCI 4 as the starting point, followed by a decreasing trend. Of these, 140 patients (9.7%) had a CCI score of 3 or higher. The high CCI group was older (70.6% vs. 64.7%, p < 0.01) and had a higher proportion of men (70.7% vs. 58.7%, p < 0.01) than the low CCI group. The high CCI group had a higher incidence of cancer than the low CCI group (77.9% vs. 65.2%, p < 0.01). The en bloc resection rate (90.0% vs. 89.3%, p = 0.79) and complete resection rate (75.7% vs. 81.2%, p = 0.12) were not significantly different between the two groups. Colorectal ESD can be safely and effectively performed in patients with various underlying medical conditions.

Expression of Apurinic/Apyrimidinic Endonuclease 1 in Colorectal Cancer and its Relation to Tumor Progression and Prognosis.

BACKGROUND/AIM: Over-expression of apurinic/apyrimidinic endonuclease 1 (APE1) has been demonstrated to be associated with cancer progression, chemo- and radioresistance in various cancers. This study examined the expression of APE1 and its relation to tumor progression and prognosis in patients with colorectal cancer (CRC). MATERIALS AND METHODS: We investigated 193 patients with CRC who received curative surgery for whom formalin-fixed and paraffin-embedded blocks were available, and long-term tumor-specific survival rate analysis was possible. The expression of APE1 was investigated by reverse transcription-polymerase chain reaction, western blotting, and immunohistochemistry in CRC and lymph node tissues. The apoptosis, proliferation, and angiogenesis of CRC cells were determined using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay, and immunohistochemical staining for Ki-67 and CD34 antibodies. RESULTS: APE1 was over-expressed in CRC and metastatic lymph node tissues compared with normal colorectal mucosa and non-metastatic lymph node tissues. Over-expression of APE1 was significantly associated with advanced stage, lymphovascular invasion, perineural invasion, deeper tumor invasion, lymph node metastasis, distant metastasis, and poor survival. Multivariate analysis demonstrated that APE1, perineural invasion, and lymph node metastasis were the independent prognostic factors associated with overall survival. The mean Ki-67 labeling index value of APE1-positive tumors was significantly higher than that of APE1-negative tumors. However, there was no significant association between APE1 expression and the apoptotic index or microvessel density. CONCLUSION: Over-expression of APE1 is significantly associated with tumor progression and poor survival in patients with CRC. Therefore, APE1 may be a novel biomarker and present a potential prognostic factor for CRC.

A disintegrin and metalloprotease 12 contributes to colorectal cancer metastasis by regulating epithelial­mesenchymal transition.

A disintegrin and metalloprotease 12 (ADAM12) and epithelial­mesenchymal transition (EMT) are linked in the metastasis of various types of cancer. The present study aimed to assess the ability of ADAM12 to induce EMT and its potential as a therapeutic target for colorectal cancer (CRC). ADAM12 expression in CRC cell lines, CRC tissues and a mouse model of peritoneal metastasis was assessed. The effect of ADAM12 on CRC EMT and metastasis was investigated using ADAM12­pcDNA6­myc and ADAM12­pGFP­C­shLenti constructs. ADAM12 overexpression enhanced the proliferation, migration, invasion and EMT of CRC cells. The phosphorylation levels of factors associated with the PI3K/Akt pathway were also increased by ADAM12 overexpression. The knockdown of ADAM12 reversed these effects. ADAM12 expression and the loss of E­cadherin expression were significantly associated with poorer survival compared with other expression statuses of both proteins. In a mouse model of peritoneal metastasis, overexpression of ADAM12 induced increased tumor weight and peritoneal carcinomatosis index compared with that in the negative control group. Conversely, knockdown of ADAM12 reversed these effects. Furthermore, E­cadherin expression was significantly decreased by overexpression of ADAM12 compared with in the negative control group. By contrast, E­cadherin expression was increased by knockdown of ADAM12 compared with in the negative control group. ADAM12 overexpression contributed to CRC metastasis by regulating EMT. In addition, in the mouse model of peritoneal metastasis, ADAM12 knockdown exhibited strong anti­metastatic action. Consequently, ADAM12 may be considered a therapeutic target for CRC metastasis.

Primary Duodenal Mucosa-associated Lymphoid Tissue Lymphoma Treated with Radiation Therapy Alone.

Primary mucosa-associated with a lymphoid tissue (MALT) lymphoma is a rare distinct subtype of non-Hodgkin's lymphoma that occurs in approximately 8% of all non-Hodgkin lymphomas. Primary gastrointestinal MALT lymphoma usually occurs in the stomach, but duodenal involvement is extremely rare. Therefore, the clinical manifestations, treatment, and prognosis of primary duodenal MALT lymphoma have not yet been validated because of its rarity. This paper reports a case of a 40-year-old male with primary duodenal MALT lymphoma who was treated successfully with radiation therapy alone. A 40-year-old male visited for a medical check-up. Esophagogastroduodenoscopy revealed whitish multi-nodular mucosal lesions in the second and third portions of the duodenum. Biopsy specimens from mucosal lesions in the duodenum were reported to be suspicious for MALT lymphoma of the duodenum. He received a total dose of 3,000 cGy in 15 fractions with external beam radiation therapy for three weeks. Three months after radiation therapy, an endoscopic examination revealed complete resolution of the duodenal lesions. The follow-up 12 months after radiation therapy showed no evidence of tumor recurrence.

Clinical Outcome and Risk Factors of Chronic Radiation Proctitis Following Pelvic Radiation Therapy.

BACKGROUND/AIM: Pelvic radiation therapy (RT) is a common treatment for malignancies, including gynecological, genitourinary, and lower gastrointestinal tract cancers. However, chronic radiation proctitis (RP) is an unavoidable side effect, and its clinical presentation varies from asymptomatic to potentially life-threatening. This study evaluated the clinical characteristics and risk factors of chronic RP. PATIENTS AND METHODS: Patients with chronic RP (212) following RT for various pelvic cancers between January 2015 and December 2021 were enrolled. Clinical characteristics of RP were analyzed retrospectively. Severity was graded according to the Radiation Therapy Oncology Group (RTOG) modified rectal toxicity score and Vienna rectoscopy score (VRS), and risk factors were statistically analyzed. RESULTS: The most common pelvic cancer observed was cervical cancer. The patients received three-dimensional conformal RT (3D-CRT), intensity-modulated RT, or a combination of 3D-CRT and intracavitary RT (ICR). Rectal bleeding occurred in 70 (33.0%) patients. Previous abdominopelvic surgery and total radiation dose significantly correlated with the RTOG score and VRS. Previous abdominopelvic surgery, ICR, and total radiation dose were associated with chronic hemorrhagic RP. All patients with chronic hemorrhagic RP were treated with argon plasma coagulation (APC). 91.4% of cases required 1-3 APC sessions to resolve the bleeding, with a mean of 1.7 sessions. CONCLUSION: Our results showed that previous abdominopelvic surgery and total radiation dose were significant risk factors related to chronic RP, while total radiation dose was related to chronic hemorrhagic RP. We also showed that APC was effective and safe for chronic hemorrhagic RP.

CD47 mediates the progression of colorectal cancer by inducing tumor cell apoptosis and angiogenesis.

CD47 is an immunoregulatory protein that is found on the cell surface and plays significant roles in cellular functions such as proliferation, apoptosis, migration, and immune homeostasis. CD47 is overexpressed in various human cancers and is associated with tumor development, progression, and poor prognosis. In this study, we analyzed the expression of CD47 to determine whether it affected the oncogenic behavior of colorectal cancer (CRC) and investigated the prognostic value of CD47 expression in patients with CRC. We investigated 468 patients with CRC who underwent curative surgery and examined the expression of CD47 in tumor and lymph node tissues by performing RT-PCR and immunohistochemistry. Apoptosis, proliferation, angiogenesis, and lymphangiogenesis were determined via a TUNEL assay and immunohistochemical staining for Ki-67, CD34, and D2-40. CD47 expression was increased in human CRC tumors and metastatic lymph nodes compared with normal colorectal mucosa and non-metastatic lymph node tissues. CD47 expression was significantly associated with perineural invasion, lymphovascular invasion, cell differentiation, cancer stage, depth of invasion, lymph node metastasis, distant metastasis, and poor survival. The mean apoptotic index and microvessel density value of CD47-positive tumors were significantly higher than those of CD47-negative tumors. However, no significant difference was observed between CD47 expression and Ki-67 labeling index or lymphatic vessel density. These results indicate that CD47 mediated the progression of CRC by inducing tumor cell apoptosis and angiogenesis.

Engulfment and Cell Motility 1 (ELMO1) Regulates Tumor Cell Behavior and Predicts Prognosis in Colorectal Cancer.

BACKGROUND/AIM: Engulfment and cell motility 1 (ELMO1) plays a crucial role in the process of migration, chemotaxis, and metastasis of tumor cells. ELMO1 has been implicated in the pathogenesis of various cancers. However, the distinct function of ELMO1 in colorectal cancer (CRC) is unclear. We determined whether ELMO1 affects the oncogenic behavior of CRC cells and investigated its prognostic value in CRC patients. MATERIALS AND METHODS: We investigated the impact of ELMO1 on tumor cell behavior using small interference RNA (siRNA) in CRC cell lines, including SW480 and DLD1. The expression of ELMO1 was investigated by reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemistry, and enzyme-linked immunosorbent assay (ELISA) in cancer tissues and sera obtained from CRC patients. RESULTS: ELMO1 knockdown suppressed tumor cell proliferation in SW480 and DLD1 cells. ELMO1 knockdown-induced apoptosis through up-regulation of caspase-3, -7, and PARP activities and down-regulation of the anti-apoptotic Mcl-1 protein. ELMO1 knockdown-induced cell-cycle arrest by decreasing cyclin D1, cyclin-dependent kinase 2, 4 and 6, and the 25C cell division cycle (CDC25C). ELMO1 knockdown suppressed tumor cell invasion and migration. The expression of E-cadherin was increased, while that of Vimentin and Claudin 1 decreased following ELMO1 knockdown. The phosphorylation levels of PDK1, Akt, and GSK-3ß and were down-regulated after ELMO1 knockdown. The expression of ELMO1 was found up-regulated in cancer tissues and sera taken from CRC patients. ELMO1 expression was significantly associated with tumor stage, lymph node metastasis, distant metastases, and poor survival. CONCLUSION: ELMO1 mediates tumor progression by increasing tumor cell motility and inhibiting apoptosis in human CRC.

Clinical outcomes of palliative self-expandable metal stent placement in right- and left-sided malignant colon obstruction: A Honam Association for the Study of Intestinal Disease (HASID) multicenter study.

Self-expandable metal stent (SEMS) placement is commonly used for palliation of left-sided malignant colorectal obstruction (MCO). However, right-sided MCO is usually treated surgically. Recent studies that compared palliative SEMS insertion and emergency surgery in right-sided MCOs have reported conflicting results. This study aimed to compare the effectiveness of palliative SEMS placement in left-sided MCOs and right-sided MCOs and to investigate the predictive factors for clinical success and risk factors for complications. Data from 469 patients who underwent palliative SEMS placement for MCO at 6 hospitals in the Honam province of South Korea between 2009 and 2018 were reviewed. Among them, 69 patients with right-sided MCO and 400 patients with left-sided MCO who underwent SEMS placement for palliative purposes were enrolled. Clinical success, overall survival, complications, and predictive factors for clinical success and risk factors for complications were included as the main outcome measures. The clinical success rates were 97.1% (65/67) in right-sided MCO patients and 88.2% (353/400) in left-sided MCO patients. Complications including stent migration, tumor ingrowth, outgrowth, perforation, bacteremia/fever, and bleeding occurred in 10.1% (7/69) of right-sided MCO patients and 19.9% (79/400) of left-sided MCO patients. The mean overall survival of right-sided MCO was 28.02 months and 18.23 months for left-sided MCO. In multivariate logistic regression analysis, T3 stage tumors and the use of uncovered stents were significant factors for the clinical success of SEMS. The use of covered stents and performance status score of 0 to 2 were independent significant risk factors for complications. Palliative SEMS placement in right-sided MCO showed better clinical success rates than left-sided MCO. The use of uncovered stents is recommended for higher clinical success rates and lower complication rates.

Differences in clinical outcomes according to the time interval between the bridge to surgery stenting and surgery for left-sided malignant colorectal obstruction.

BACKGROUND: Self-expandable metal stent (SEMS) placement is commonly used as a bridge to surgery (BTS) for left-sided malignant colorectal obstruction (MCO). However, the optimal time interval between BTS stenting and surgery for left-sided MCO is unclear, and the results of previous studies are conflicting. This study aimed to determine the differences in clinical outcomes according to the time interval between BTS stenting and surgery in left-sided MCO. METHODS: Data from 594 patients who underwent SEMS placement for MCO between January 2009 and December 2018 were reviewed. Among them, 148 patients who underwent SEMS placement as BTS treatment and curative surgery were enrolled. The enrolled patients were divided into three groups according to the interval between BTS stenting and surgery: group 1 (interval ≤2 weeks), group 2 (interval 2-3 weeks), and group 3 (interval >3 weeks). RESULTS: Group 2 and 3 patients underwent significantly higher rates of laparoscopic surgery than those in group 1 (83.7, 81.0 vs. 53.2 %, respectively; P=0.003, P=0.003, respectively). Also, rates of stoma formation directly after resection were significantly higher in group 1 compared to groups 2 and 3 (21.3 vs 2.3, 6.9%, respectively; P=0.008, P=0.043, respectively). Bridging interval had no effect on SEMS-related complications, resection-related complications, 90-day mortality, permanent stoma formation, 3-year disease-free survival, and 3-year overall survival. CONCLUSIONS: A bridging interval of > 2 weeks between BTS stenting and surgery for left-sided MCO is preferable for lower stoma formation rates and higher rates of laparoscopic approach operation, with no difference in short-term and long-term outcomes including complication, mortality, and survival.

Primary Esophageal Malignant Melanoma in Korea: Clinical features, Management and Prognosis.

Primary esophageal melanoma is a rare disease with a poor prognosis. To date, 18 cases have been reported in Korea. Four patients visited the Chonnam National University Hwasun Hospital with dysphagia, followed by epigastric pain and discomfort, odynophagia, and weight loss. Esophagogastroduodenoscopy revealed a black pigmented polypoid mass, protruding mass, or black-pigmented flat lesions. Two patients had distant metastases and lymphadenopathies in imaging studies. Two patients underwent esophagectomy and intrathoracic esophagogastrostomy. One patient was treated with chemotherapy and interferon-alpha. The other patient declined further treatment. The routine histology using H&E revealed brown-colored atypical melanocytes. Immunohistochemical staining exhibited strong reactivity for Melan-A, S-100, and HMB-45 proteins. The biopsy specimens were interpreted to be malignant melanoma. One patient had multiple distant metastases 13 months after surgery. The other patient had no recurrence for 33 months after surgery. The patient treated with chemotherapy and interferon-alpha showed disease progression in the follow-up examination. Primary esophageal melanoma in Korea is a rare disease characterized by aggressive behavior, early metastasis, and poor prognosis.

Case report of gastric syphilis in Korea: Clinical features, pathology, management, and prognosis.

RATIONALE: Syphilis is a contagious infectious disease caused by Treponema pallidum. Gastric involvement of syphilis is rare and has nonspecific gastrointestinal symptoms and endoscopic findings. To date, 16 cases have been reported in Korea. Here, we report 2 additional cases of gastric syphilis in men in their 30 second. PATIENTS CONCERNS: Two 35- and 33-year-old men presented with epigastric pain. DIAGNOSIS: The serum venereal disease research laboratory and fluorescent treponemal antibody absorption tests were positive. Esophagogastroduodenoscopy showed multiple variable-sized flat elevated lesions and geographic ulcers with whitish exudates in the antrum and body. Warthin-Starry silver staining of endoscopic biopsy specimens confirmed gastric syphilis. INTERVENTIONS: The patients were treated with an intramuscular injection of 2.4 million units of benzathine penicillin once a week for 3 weeks. OUTCOMES: Clinical symptoms and gastric lesions were completely resolved. LESSONS: First, gastric syphilis, despite its rarity and nonspecific symptoms and endoscopic findings, should be considered in a rare extracutaneous presentation of syphilis. Second, a high index of clinical suspicion and an accurate diagnosis based on a combination of clinical, radiological, endoscopic, serologic, and histopathologic findings provide an opportunity to identify and treat patients with gastric syphilis.

Rectal inflammatory myofibroblastic tumor: Case report and literature review.

RATIONALE: Rectal inflammatory myofibroblastic tumor (IMT) is an extremely rare mesenchymal tumor characterized by a mixture of spindle-shaped myofibroblasts or fibroblasts and inflammatory infiltration of lymphocytes and plasma cells. To date, only 8 cases of rectal IMT have been reported. Herein, we report an additional case of rectal IMT in a 28-year-old woman. PATIENT CONCERNS: A 28-year-old woman presented with abdominal pain and hematochezia. DIAGNOSES: Colonoscopy showed a 3.0-cm subepithelial tumor with central ulceration, covered by white exudate in the rectum. Rectal magnetic resonance imaging revealed a 4.0 × 3.0-cm-sized well-defined subepithelial tumor in the right wall of the rectum, with suspicious right perirectal fat infiltration. INTERVENTIONS: Laparoscopic anterior resection was performed. Microscopic examination of the surgical specimen revealed bland-looking spindle cells intermingled with lymphoplasma cells. Immunohistochemistry and fluorescence in situ hybridization showed anaplastic lymphoma kinase positivity and anaplastic lymphoma kinase positivity rearrangement. Rectal IMT was confirmed based on histological, immunohistochemical, and fluorescence in situ hybridization findings. The patient was doing well without evidence of tumor recurrence 1 year after the surgery. LESSONS: Rectal IMT, despite its rarity, should be considered in the differential diagnosis of rectal cancer. Second, an accurate histopathologic diagnosis and complete surgical resection can be the most important approaches to offer a chance for the cure of rectal IMT.

Predictors of clinical outcomes of self-expandable metal stent treatment for malignant colorectal obstruction: A Honam Association for the Study of Intestinal Disease (HASID) multicenter study.

ABSTRACT: There has been increased use of self-expandable metal stents (SEMS) in treating malignant colorectal obstruction (MCO). The aim of this study was to investigate factors that are associated with the outcomes of SEMS placement for MCO.Clinical data from patients who underwent SEMS placement for MCO at 6 hospitals in Honam province of South Korea between 2009 and 2018 were reviewed retrospectively. Eight hundred two patients were identified and their data were analyzed. Technical success, clinical success, complications, and predictors of outcome were included as main outcome measures.Technical and clinical success rates were 98.8% (792/802) and 90.1% (723/802), respectively. Complications including stent migration, stent occlusion due to tumor ingrowth and outgrowth, perforation, bacteremia/fever, and bleeding occurred in 123 (15.3%) patients. In multivariate regression analyses, procedure time was significantly associated with the technical success of SEMS placement (P = .001). Longer length of obstruction, the use of covered stent, and longer procedure time were significant independent predictive factors for the clinical success of SEMS placement (odds ratio [OR] 0.974 (95% confidence interval [CI] 0.950-0.990); P = .043, OR 0.255 (95% CI 0.138-0.471); P < .001, and OR 0.957 (95% CI 0.931-0.984); P = .002, respectively). Stage IV colorectal cancer and the use of covered stent were significant independent predictive factors for the development of complications after SEMS placement (OR 2.428 (95% CI 1.407-4.188); P = .001 and OR 3.329 (95% CI 2.060-5.378); P < .001, respectively).Longer length of obstruction, the use of covered stent, and longer procedure time were associated with lower clinical success rates. Having stage IV colorectal cancer and the use of covered stents were associated with an increased risk of complications.

A Disintegrin and Metalloprotease 12 Promotes Tumor Progression by Inhibiting Apoptosis in Human Colorectal Cancer.

A disintegrin and metalloprotease 12 (ADAM12) has been implicated in cell growth, tumor formation, and metastasis. Therefore, we evaluated the role of ADAM12 in colorectal cancer (CRC) progression and prognosis, and elucidated whether targeted downregulation of ADAM12 could lead to therapeutic sensitization. The effect of ADAM12 on tumor cell behavior was assessed in CRC cell lines, CRC tissues, and a mouse xenograft model. ADAM12 overexpression enhanced proliferation, inhibited apoptosis, and acted as positive regulator of cell cycle progression in CRC cells. Phosphorylation of PTEN was decreased and that of Akt was increased by ADAM12 overexpression. These results were reversed upon ADAM12 knockdown. ADAM12 overexpression was significantly associated with the cancer stage, depth of invasion, lymph node metastasis, distant metastasis, and poor survival in CRC patients. In a mouse xenograft model, tumor area, volume, and weight were significantly greater for the ADAM12-pcDNA6-myc-transfected group than for the empty-pcDNA6-myc-transfected group, and significantly lower for the ADAM12-pGFP-C-shLenti-transfected group than for the scrambled pGFP-C-shLenti-transfected group. In conclusion, ADAM12 overexpression is essential for the growth and progression of CRC. Furthermore, ADAM12 knockdown reveals potent anti-tumor activity in a mouse xenograft model. Thus, ADAM12 may serve as a promising biomarker and/or therapeutic target in CRC.

Colonic Mucosa-associated Lymphoid Tissue Lymphoma Treated by Radiation Therapy: Report of a Case and Literature Review.

Mucosa-associated lymphoid tissue (MALT) lymphoma predominantly involves the gastrointestinal tract, with the stomach being the most commonly affected site. Colonic involvement is quite rare. Hence, the etiology, clinical characteristics, treatment, and outcome of colonic MALT lymphoma are not well established. This paper reports a case of MALT lymphoma of the transverse colon, presenting as a subepithelial tumor in a 50-year-old woman. The patient received 3,060 cGy in 17 fractions with external beam radiation therapy for three weeks. At 2 months after radiation therapy, a colonoscopy examination revealed complete resolution and a scar change of the lesion. The follow-up at 24 months revealed no evidence of tumor recurrence after radiation therapy.

Engulfment and cell motility 1 promotes tumor progression via the modulation of tumor cell survival in gastric cancer.

BACKGROUND/AIM: Engulfment and cell motility 1 (ELMO1) protein has been implicated in phagocytosis of apoptotic cells, cell migration, neurite outgrowth, cancer cell invasion and metastasis, and poor prognosis in various cancers. We investigated the role of ELMO1 in mediating the oncogenic behavior of gastric cancer (GC) cells. We also investigated the correlation between expression of ELMO1 in GC tissues and various clinicopathological parameters. METHODS: We studied the impact of ELMO1 on tumor cell behavior using the pcDNA-myc vector and small interfering RNA in AGS and SNU1750 GC cell lines. We performed western blotting and immunohistochemistry to investigate the expression of ELMO1 in GC cells and tissues. RESULTS: ELMO1 overexpression inhibited apoptosis via the modulation of PARP, caspase-3 and caspase-7 in GC cells. ELMO1 overexpression led to significant increase in the number of migrating and invading GC cells. The expression of E-cadherin decreased and that of Snail increased in GC cells upon ELMO1 overexpression. Phosphorylation of PI3K/Akt and GSK-3ß was increased and that of ß-catenin was decreased upon ELMO1 overexpression in GC cells. These results were reversed after ELMO1 knockdown. ELMO1 expression was significantly associated with tumor size, cancer stage, lymph node metastasis and survival. ELMO1-positive tumors had significantly higher mean of Ki-67 labeling index than ELMO1-negative tumors. There was no significant relationship between ELMO1 expression and the mean value of the apoptotic index. CONCLUSIONS: Our results indicate that ELMO1 promotes tumor progression by modulating tumor cell survival in human GC.

Novel biomarkers for the diagnosis and prognosis of colorectal cancer.

Colorectal cancer (CRC) is among the most common malignancies and remains a major cause of cancer-related death worldwide. Despite recent advances in surgical and multimodal therapies, the overall survival of advanced CRC patients remains very low. Cancer progression, including invasion and metastasis, is a major cause of death among CRC patients. The underlying mechanisms of action resulting in cancer progression are beginning to unravel. The reported molecular and biochemical mechanisms that might contribute to the phenotypic changes in favor of carcinogenesis include apoptosis inhibition, enhanced tumor cell proliferation, increased invasiveness, cell adhesion perturbations, angiogenesis promotion, and immune surveillance inhibition. These events may contribute to the development and progression of cancer. A biomarker is a molecule that can be detected in tissue, blood, or stool samples to allow the identification of pathological conditions such as cancer. Thus, it would be beneficial to identify reliable and practical molecular biomarkers that aid in the diagnostic and therapeutic processes of CRC. Recent research has targeted the development of biomarkers that aid in the early diagnosis and prognostic stratification of CRC. Despite that, the identification of diagnostic, prognostic, and/or predictive biomarkers remains challenging, and previously identified biomarkers might be insufficient to be clinically applicable or offer high patient acceptability. Here, we discuss recent advances in the development of molecular biomarkers for their potential usefulness in early and less-invasive diagnosis, treatment, and follow-up of CRC.