High-Dose Vitamin C Tends to Kill Colorectal Cancer with High MALAT1 Expression

Background. Vitamin C (Vc) deficiency is frequently observed in cancer sites and has been proposed to have an antitumor effect. However, the mechanism of Vc’s killing effect is not clear. Besides, epigenetic alterations exhibit significant effects on colorectal cancer (CRC). This study aimed to explore the mechanism of Vc’s killing effect and its association to epigenetic alterations in CRC. Methods. Cell morphology, apoptosis, proliferation, and cycle were assayed to test Vc’s suppressive function in CRC cell lines. Xenograft and peritoneal implantation metastasis models were performed to evaluate the high-dose Vc’s inhibitory effect on tumor growth and metastasis. Immunohistochemistry was used to measure CD31 expression in solid tumors. A literature summary was applied for screening differently expressed long noncoding RNAs (lncRNAs) in CRC tissues and was closely associated with CRC progression. The qPCR was used to detect the expression of these lncRNAs. The association between Vc and metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) was evaluated in MALAT1-transfected CRC cells and a xenograft model. Results. Vc was confirmed to function in proliferation suppression, apoptosis induction, and S phase arresting in CRC cell lines. High-dose Vc, but not physiologically low-dose Vc, was identified as a suppressive function on tumor growth in xenograft models and an inhibitory effect on implantation metastasis in peritoneal implantation metastasis mice. Furthermore, a consistent downregulation of MALAT1 induced by Vc was verified among CRC cell lines and tumor tissues from both mouse models. Finally, experiments on MALAT1-knockdown CRC cells and its xenograft model suggested that Vc had a tendency in killing CRC with high MALAT1 expression. Conclusions. Our findings demonstrate that high-dose Vc has more efficiency in suppressing CRC with higher MALAT1 expression. It gives high-dose Vc the possibility of a better curative effect on CRC with overexpressed MALAT1. Further clinical studies are still needed.

Endometrial cancer with implantation metastasis to vagina: a case report

Authors present a case of vaginal implantation metastasis following a diagnosis of endometrial cancer. A 58-year-old lady presented with postmenopausal bleeding and was later diagnosed to have endometrial cancer. She underwent an extra-fascial hysterectomy and bilateral salpingo-oophrorectomy with pelvic lymphadenectomy for Stage 3A endometrioid adenocarcinoma of the endometrium. The lymph nodes and cervix were free from the disease and no lymphovascular invasion was seen on the pathological specimen. She defaulted adjuvant radiotherapy and was lost to follow up. Six months later she had a tumour recurrence at the vaginal introitus just below the urethral orifice and awal from the vaginal vault with similar histopathological findings as previous cancer. This case highlights the rare occurrence of implantation metastasis of endometrial cancer.

Gastric cancer with high risk of intraperitoneal progression: clinical course and current treatments

Locally advanced gastric cancer with a high risk of intraperitoneal progression is characterized by poor prognosis. After radical surgery, most patients die during the first two years post-operation as a result of disease progression. The prevailing type of progression and the leading cause of death in patients with gastric cancer is implantation metastasis. The main risk factors for peritoneal carcinomatosis in such patients include: gastric tumor invasion into serosa, the presence of tumor cells in peritoneal washings, the largeness of the tumor as accompanied by extensive serous lesions, infiltrative type of tumor growth, histological variants of gastric cancer prone to implantation metastasis and metastatic lesions in regional lymph nodes. Systemic chemotherapy does not provide effective eradication of subclinical peritoneal carcinomatosis in patients with locally advanced gastric cancer. The vast majority of patients who suffer from locally advanced gastric cancer and run a high risk of implantation metastasis are characterized by subclinical peritoneal dissemination at primary diagnosis, which means a rapidly fatal prognosis for such patients. In recent years, however, the paradigm of treatment of locally advanced gastric cancer has changed: a combination of surgery and adjuvant hyperthermic intraperitoneal chemotherapy is used increasingly, and presents an alternative to the previously accepted surgery only approach. It is also likely to increase the survival rate.

Laparotomy site implantation metastasis of carcinoma of the papilla of Vater

Introduction Carcinomas of the papilla of Vater make up a heterogeneous group of tumours arising from different types of epithelium. Regional lymph nodes, liver and lungs are the primary sites of metastatic progression of these tumours. Case presentation We present a patient with an abdominal incision site metastasis of low-grade (mixed type) adenocarcinoma of the papilla of Vater one year after pylorus-preserving pancreaticoduodenectomy. Implantation metastasis of low-grade ampullary carcinoma in the laparotomy wound after open Whipple’s procedure is unusual. Conclusion Adjuvant chemoradiation might be considered for patients with low-grade localised disease as a potentially preventative measure vs. metastatic progression.