The Role of Stem Cell DNA Methylation in Colorectal Carcinogenesis

Stems cells of the colon crypt are the origin of colon mature cells. Colorectal cancer cells are also suggested to originate from crypt stem cells undergoing a series of epigenetic and genetic alterations. Aberrant methylation plays important roles in early carcinogenesis and lead to altered gene expression and regulation, resulting in accumulation of damages to cell function and ultimately, malignant transformation. Aberrances in hypermethylation and hypomethylation act in different mechanism through the regulation of various genes during CSC carcinogenesis, and both of them play crucial roles in stem cell differentiation towards cancer cells. A large majority of epigenetic and genetic abnormalities that work coordinately in colorectal carcinogenesis are related to cell growth and division, indicating that the intrinsic abnormalities of CRC lie in dysregulation of basic cellular processes. Detection of abnormal methylation can be used in cancer screening and early detection, while reversal of aberrant methylation using drugs may have potential in cancer therapy. This review will provide an overview on the roles of aberrant methylation and a summary of genes that are affected during CRC carcinogenesis.     

大肠癌干细胞相关Wnt信号通路调控分子的研究进展

大肠癌是中国发病率排名第三的癌症。虽然近年来手术技术和术后化疗效果已经取得不小的进展,但大肠癌的预后仍不令人满意,主要原因是肿瘤的复发和转移。大肠癌干细胞Wnt信号通路在肿瘤复发和转移中起重要作用,并已成为抗癌药物研发的新靶点。大肠癌干细胞Wnt信号通路的失调导致细胞内β-catenin水平升高,继而激活一系列致癌相关基因。因此,如果针对Wnt信号通路的小分子靶向药物可阻止或逆转这些异常变化,将有助于治疗大肠癌。本文对以Wnt通路为靶标的小分子药物的研究现状进行了回顾,并展望其未来可能的发展方向。     

The application of SFDI and LSI system to evaluate the blood perfusion in skin flap mouse model

Lasers in Medical Science - The aim of this study is to evaluate whether the blood perfusion to tissues for detecting ischemic necrosis can be quantitatively monitored by spatial frequency domain...     

Weekly cisplatin induction chemotherapy in the treatment of recurrent cervical carcinoma

Sixty-nine patients with recurrent cervical carcinoma were treated with weekly cisplatin induction chemotherapy. A 27% objective response was obtained in 67 evaluable patients. The highest responses were seen in liver (33%), supraclavicular nodes (40%), and lung (48%), whereas only one out of 24 (4.2%) patients with central recurrence responded. Consolidation therapy with cisplatin combinations administered on a monthly basis did not enhance response to cisplatin. Cisplatin induction therapy was well tolerated with minimal toxicity.     

Malignant peritoneal cytology in stage I endometrial adenocarcinoma: the effect of progesterone therapy (a preliminary report)

From February 1982-June 1986, 25 consecutive patients with surgical stage I endometrial adenocarcinoma (no evidence of metastasis at surgery or occult cervical or adnexal involvement on histopathologic review) and malignant peritoneal cytologic washings were treated with progesterone therapy. Twenty-two patients have undergone a second look laparoscopy and repeat cytologic washings, one of those also underwent a third look laparoscopy. Two patients refused second look laparoscopy, and in a third patient laparoscopy was medically contraindicated; all three have no evidence of disease (NED) at 15, 46, and 64 months respectively and are off therapy. Of the 22 patients who underwent second look laparoscopy, 21 (95%) had no macroscopic evidence of recurrent endometrial carcinoma and repeat negative peritoneal cytology; 1 patient (5%) had persistent malignant peritoneal cytology but was NED at third look laparoscopy one year later. All 25 patients are off progesterone therapy and remain clinically NED from 12-64 months. Although progesterone therapy for malignant peritoneal cytology resulted in a 100% reversal of malignant peritoneal cytology to normal in the 22 patients who underwent second or third look laparoscopy and all 25 patients remain clinically NED, the true value of progesterone therapy can only be ascertained by a randomized trial of progesterone versus no therapy.     

Safety and potential hazards in the current applications of ultrasound in obstetrics and gynecology

The safety and potential hazards in the current applications of ultrasound in obstetrics and gynecology are discussed. The author has made an attempt to provide a perspective to enable interpretation of future experimental results in terms of health hazards for humans.