Characterization of the cholesterol efflux of apolipoprotein E-containing high-density lipoprotein in THP-1 cells.

High-density lipoprotein (HDL), also known as antiatherogenic lipoprotein, consists of heterogeneous particles in terms of size, density and composition, suggesting differences among HDL subclasses in characteristics and functions. We investigated the role of apolipoprotein E (apoE)-containing HDL, a minor HDL subclass, in the cholesterol efflux capacity (CEC) of HDL, which is its predominant atheroprotective function. The CEC of apoE-containing HDL was similar to that of apoE-deficient HDL, but the former exhibited a greater rate increase (1.48-fold) compared to that of the latter (1.10-fold) by the stimulation of THP-1 macrophages with the Liver X Receptor (LXR) agonist. No difference in CEC was observed without the LXR agonist between apoA-I, the main apolipoprotein in HDL, and apoE, whereas the increase in CEC in response to treatment with the LXR agonist was greater for apoA-I (4.25-fold) than for apoE (2.22-fold). Furthermore, the increase in the CEC of apoE-containing HDL induced by the LXR agonist was significantly reduced by treatment with glyburide, an inhibitor of ATP-binding cassette transporter A1 (ABCA1). These results suggest that apoE-containing HDL, unlike apoE-deficient HDL, is involved in cholesterol efflux via ABCA1.

[A resected case of signet-ring cell carcinoma of the rectum].

Here, we present the case of a 76-year-old woman who consulted us in April 2010, following a positive fecal occult blood test, and was diagnosed with lower rectal cancer. Signet-ring cell carcinoma was diagnosed by histology. Because hydronephrosis of both sides was considered the cause of dissemination of the tumor, only chemotherapy was performed. After the eighth course of XELOX+bevacizumab treatment, hydronephrosis of both sides improved and the tumor marker level became normal. An abdominoperineal rectal resection was performed in February 2011. The results of pathological examination of the resected specimen showed complete response. After the operation, the tumor marker level was elevated, and recurrence in the pelvic cavity and multiple bone metastases were detected by positron emission tomography/ computed tomography. Chemotherapy has now been resumed. Signet-ring cell carcinoma is rare in colorectal cancer. The frequency of multiple organ metastases is high, and the growth rate of the tumor is also high. Poor prognosis compared to the usual colorectal cancer has been reported.

[A case report of primary adenocarcinoma of small intestine].

This is an account of a case of primary adenocarcinoma of the small intestine with peritoneal dissemination successfully treated with chemotherapy. A 64-year-old woman was admitted with a complaint of severe abdominal distension. Abdominal computerized tomography revealed a bowel obstruction with tumor and the remarkable small bowel dilation of oral side of tumor. The tumor was found at surgery to be at the ileum 15 cm proximal from the ileocecal region. Peritoneal dissemination was recognized around the ileocecal region, so ileum partial resection was performed for the primary cancer lesion and dissemination region. Pathological diagnosis of the resected specimen was adenocarcinoma with lymph nodes metastasis. The peritoneal dissemination consisted of metastatic adenocarcinoma from small intestine. After an operation, internal use of S-1 was performed as adjuvant chemotherapy. But a recurrent lesion at the ovarium was detected 6 months after surgery. The patient was subsequently treated with resection of the ovarium. For lung metastasis, the combination chemotherapy with mFOLFOX6 + bevacizumab was administered. Primary small intestinal adenocarcinoma is a rare disease, and it is often diagnosed as advanced cancer because of few characteristic symptoms. So carcinoma of the small intestine usually has a poor prognosis.