The Prokineticin 2 (PROK2) is correlated with indispensable in maintaining the homeostasis of healthy human tissues. Herein, we examined the role of PROK2 in human colorectal cancer.After total RNA extraction from 6 colorectal cancer cell lines, we examined the expression of PROK2 mRNA. For investigating angiogenesis and tumor growth in mice, the PROK2 gene was transfected into colorectal cancer cell lines having low PROK2 mRNA expression. In addition, small interfering RNA (siRNA) was transfected into colorectal cancer cell lines having high PROK2 mRNA expression for investigation of angiogenesis and tumor growth in mice.From 6 colorectal cancer cell lines studied, PROK2 mRNA expression was increased in 3 cell lines. When the PROK2 gene was transfected into the colorectal cancer cell line with low PROK2 mRNA expression, angiogenesis and tumor growth in mice increased significantly compared to the cell line with the control vector.When PROK2 siRNA was transfected into colorectal cancer cell lines with high PROK2 mRNA expression, angiogenesis and tumor growth in mice were suppressed significantly compared to the cell line with siRNA (control). This is the first report of the association of PROK2 as an angiogenic growth factor in colorectal cancer.

Mixed adenoneuroendocrine carcinoma (MANEC) of the colon is rare and has a poor prognosis. Here, we report a case of MANEC in the ascending colon, in which streptozocin monotherapy achieved a partial response. A 36-year-old woman underwent right hemicolectomy for colonic polyposis, which included ascending colon cancer. Pathological examination revealed that some mucosal polyps were adenocarcinoma while one submucosal polyp was neuroendocrine carcinoma. Adjuvant chemotherapy was not administered, and 5 months after the operation, multiple liver metastases were identified. She was started on modified (5-FU, leucovorin, oxaliplatin) followed by XELOX (capecitabine, oxaliplatin) plus bevacizumab. Although these regimens helped achieve stable disease, computed tomography showed that the hepatic metastatic lesions had enlarged 4 months later. Subsequently, the regimen was changed to streptozocin monotherapy (1000 mg/m 2 , weekly). After 5 cycles, the regimen achieved partial response and was continued for a total of 17 courses without significant adverse events until progressive disease. As a third-line chemotherapy regimen, cisplatin plus etoposide (EP) was administered. The EP regimen reduced the size of the hepatic and ovarian metastatic lesions but severe neutropenia and anemia was observed. Amrubicin monotherapy was also administered as fourth-line chemotherapy but a good clinical response was not detected, and the patient died 20 months after the operation. Streptozocin monotherapy has the potential to be a therapeutic option for mixed adenoneuroendocrine carcinoma of the colon.

Background Prokineticin 1 (PROK1) was reported as an angiogenic factor, which is associated with tumor progression, cell invasion, and metastasis in colorectal cancer. Although the association between PROK1 expression in primary cancer lesion and patient prognosis was reported, it is unclear whether plasma PROK1 concentration may be a predictive factor in colorectal cancer patients. This study investigated the association between PROK1 concentration in plasma and prognosis in colorectal cancer patients. Methods We measured preoperative PROK1 plasma levels using ELISA method, while PROK1 expression in primary cancer lesion was evaluated using immunohistochemistry (IHC). The association between plasma PROK1 levels and cancer-related survival rate (CRS) was evaluated. Additionally, we examined whether simultaneous PROK1 expression in both primary cancer lesions and plasma was correlated with CRS. The cancer-related survival rate was calculated using the Kaplan-Meier method, and survival estimates were compared using the log-rank test. Results We have gathered eligible 130 CRC patients retrospectively. Out of 130 patients, 61 (46.9%) were positive on IHC in primary cancer, and 69 (53.1%) were negative, while 43 (33.1%) had high-value PROK1 in plasma. Out of these 43, 30 (25.4%) also had concomitant higher IHC expression in primary cancer. The plasma PROK1 levels tended to increase with advancing stages. The plasma PROK1-positive group had a lower 5-year CRS than the negative group (63.6% vs. 88.2%; P = 0.006). Additionally, simultaneous PROK1 expression was associated with a more significant decrease of 5-year CRS than both negative groups in all stages (76.2% vs. 92.5%; P = 0.003) and stage III (59.3% vs. 84.5%; P = 0.047). Multivariate analysis showed simultaneous PROK1 expression was independently associated with worse CRS (HR, 1.97; 95% CI 1.20‑3.24, P < 0.01). Conclusion PROK1 expression in preoperative plasma reflects poor prognosis in patients undergoing curative resection for colorectal cancer. The plasma PROK1 level may be a potential predictive marker, especially in stage III colorectal cancer patients.

We discuss a case of surgically treated chronic idiopathic colonic pseudo-obstruction (CICP). A 74-year-old woman with a history of sigmoidectomy visited our hospital because of dyspnea and lower abdominal pain. Chest and abdominal X-ray imaging showed a markedly dilated transverse and descending colon and elevation of the left diaphragm. Suctioning of colon gas and stool by colonoscopy was performed, but proved ineffective. We diagnosed CICP and performed surgery. Intraoperatively, we resected the dilated colon and plicated the elevated diaphragm. Postoperatively, chest X-rays showed the fixed left diaphragm at the normal location. The postoperative course has been uneventful and all symptoms resolved. Key words：eventration of the diaphragm，chronic idiopathic colonic pseudo-obstruction

Introduction: The Boari flap technique is a unique urinary tract reconstruction procedure performed after resection of the urinary tract. However, few previous reports have described the application of this technique to gastrointestinal cancer. Moreover, we have not found any papers describing the long-term prognosis. We report a case of right ureteral tract resection followed by Boari flap reconstruction for rectosigmoid carcinoma, with survival for 108 months without any urological complications. Case presentation: A woman in her 50s was diagnosed with rectosigmoid caner by local physician and referred to our institution. Computed tomography revealed right hydronephrosis due to rectosigmoid cancer invasion at the lower two-thirds of the right ureter. During laparotomy, massive lymphatic infiltration from the primary lesion to right ureter was observed. After primary tumor resection with lower ureter excision, the Boari flap procedure was performed to reconstruct the ureteral deficit. Postoperative course was uneventful, and she was discharged on postoperative day 20. The patient has been followed every 4 months for 9 years with no recurrence or unpleasant symptoms. Discussion: This technique is usually performed to manage specific conditions such as ureteral stenosis caused by ureteral calculi, retroperitoneal fibrosis, and gynecological disorders. This procedure should be reconsidered as a possible option for gastrointestinal malignant cases instead of nephrostomy or cutaneous ureterostomy, given the low rate of complications and high patient satisfaction. Conclusion: The Boari flap technique is particularly useful for bridging between the ureter and bladder in cases of colorectal malignancy with combined resection of the lower urinary tract.