[Downregulation of AKR1B10 gene expression in colorectal cancer].

Colorectal cancer is one of the most common cancers in the world. In our work changes of AKR1B1 and AKR1B10 gene expression levels in colorectal tumors were studied. Their potential diagnostic value was previously shown for several other cancer types. These genes encode aldoso reductases, which belong to the aldo-keto reductases superfamily consisting of enzymes capable to reduce numerous aromatic and aliphatic aldehydes and ketones. They are also involved into retinoid metabolism and cancerogenesis. We have carried out comparative analysis of mRNA levels of AKR1B1 and AKR1B10 genes in paired samples of normal and colorectal tumor tissues using RT-PCR and quantitative PCR. We have shown for the first time the decrease of activity of these genes in colorectal carcinomas. Significant reduction of AKR1B10 mRNA level was detected in the most of tumor samples (88%, 65/74) even at the early stages of malignancy, and in more than 60% of cases this downregulation was much higher than 10 folds. The decrease of AKR1B1 mRNA level was shown in 10% of tumors only. Therefore, we have detected quite different mRNA expression patterns in colorectal cancer for these two structurally similar genes. These data could indicate different functional roles of these two genes in colorectum. The significant decrease of AKR1B10 mRNA in most samples of colorectal cancer could be considered as potential diagnostic marker of this type of cancer.

[Detection of genetic mutations in clinical specimens from cancer patients: comparison of NIRCA and SSCP scanning methods].

Specimens of tumor with K-RAS mutations were used to compare SSCP and NIRCA efficiencies in screening long target regions for dispersed point mutations. K-RAS mutations were detected in 5 out of 10 tumor tissue samples from colorectal cancer patients (in codon 12-4 and codon 13-1). Mutant alleles occurred most frequently in adenocarcinoma of the ascending colon and rectum. Both methods proved equally efficient. In certain situations, they may be combined or used as complementary. NIRCA is suitable for screening relatively long sequences (up to 1kb) while SSCP is less sophisticated, robust and allows for mutant bands to be extracted from polyacrylamide gel when required.

[Restoration of bowel tube continuity in patients with colostomies]. / Vosstanovlenie nepreryvnosti kishichnoí trubki u bol'nykh s kolostomoí.

The experience of restorative operations conducted within 1980-1995 in 186 patients with one-tube and separated two-tube colostomy gainred in proctologic clinic is reviewed. 179 patients suffered from cancer of the colon. The causes of performing colostomy are outlined. The main stages of restorative operation in two-tube colostomy are described. Peculiarities of colonic anastomosis formation after resection of bowel segment bearing fistula are considered, the resection being performed with the help of laser scalpel. Possibilities of the use of suturing apparatus AKA, peculiarities and advantage of its application in carrying out restorative surgical intervention in 69 patients after Hartmann's operation are demonstrated. The data of reconstructive-restorative operations in conditions of short rectal stump (modification of Duhamel operation), information about complications in restorative operations and their causes are analyzed. The mortality rate made up 2.2%. Possibility and expediency of restorative operations in patients with colostomy accompanied by metastases are discussed.

[The restoration of the continuity of the intestinal tube after the Hartmann operation]. / Vosstanovlenie nepreryvnosti kishechnoi trubki posle operatsii Gartmana.

The results of reconstructive surgery after the Hartmann [correction of Gartman] operation in 67 patients have been analysed. The proper timing of surgery is advocated, various types of restoration of uninterrupted intestinal tube are described: manual anastomosis, use of a special device, Duhamel type of operation, bringing down of the colon. The frequency of anastomotic incompetence is 10%, postoperative mortality--4.5%.

[The prognostic significance of the inversion of mucus formation in patients with recurrent rectal cancer]. / Prognosticheskoe znachenie inversii slizeobrazovaniia u bol'nykh s retsidiviruiushchim rakom priamoi kishki.

The presence in the mucous membrane around the tumor of moderate or small amounts of sulfomucins as well as a complete absence of sulfo- and cyalomucins in the tumor cells are indices of a favourable prognosis. Unfavourable factors indicating the probability of rectal carcinoma recurrence after the operation are as follows: the presence in the tumour cells of a moderate amount of cyalomucins and/or a small amount of sulfomucins as well as a complete absence of sulfomucins in the mucous membrane near tumour. The rule for the individual prognosis has been worked out. Its statistical significance is 80%.

[The ultrastructural factors of the individual prognosis in rectal cancer in patients following radical surgical treatment]. / Ul'trastrukturnye faktory individual'nogo prognoza pri rake priamoi kishki u bol'nykh posle radikal'nogo khirurgicheskogo lecheniia.

Multifactorial analysis of the prognostic diagnosis of 39 main clinical, morphological and ultrastructural traits in 109 patients with rectum carcinoma is performed on the basis of computer EC-1045/230 program and algorithmic complex. The optimal complex of the traits is established possessing the maximum information value for prognosis of the 2-, 3- and 5-year survival of patients with this tumour. Three rules are formed for the individual prognosis of a favourable and unfavourable issue of the disease after the radical surgery. The value (in %) of these rules for the prognosis was determined: 79,86 and 92% for the 2-, 3- and 5-year survival, respectively. This is the precision with which one or another prognosis can be predicted.

[Malignant nonepithelial tumors of the rectum]. / Neépitelial'nye zlokachestvennye opukholi priamoi kishki.

Nonepithelial malignancies of the rectum are extremely rare making up 0.34% of all rectal neoplasms only. Clinical course, diagnosis and treatment of 8 patients with rectal sarcoma are described. Electron microscopy is helpful in differentiating between various types of sarcoma.

[Nonorganic retroperitoneal neoplasms of the pelvis]. / Neorgannye zabriushinnye opukholi taza.

The results of observations over 116 patients with nonorganic retroperitoneal tumors of the pelvis in the diagnosis of which computerized and ultrasonic tomography were used among other methods showed these methods to expand the possibilities of early diagnosis significantly. Analysis of 83 operations conducted on patients with nonorganic tumors of the pelvis revealed the main reasons why a radical operative intervention failed to be performed. Hemorrhage and pyo-inflammatory processes in the pelvic fat were the most common and serious complications in the postoperative period.

[The prognostic significance of the ultrastructural characteristics of human rectal cancer]. / Prognosticheskoe znachenie ul'trastrukturnykh osobennostei raka priamoi kishki cheloveka.

A retrospective study of the ultrastructure of rectal tumors in patients with favorable and unfavorable prognosis was undertaken. It established favorable postoperative course and prognosis in tumors containing more than half undifferentiated cells. Conversely, tumors in which malignant cells with electron microscopy-identifiable signs of differentiation (retaining features of normal cells) prevailed and those containing equal fractions of well- and poorly differentiated cells involve early development of metastasis and sometimes recurrences.

[Multiple primary cancer of the gastro-intestinal tract]. / O pervichno-mnozhestvennom rake zheludochno-kishechnogo trakta.

Peculiarities of the clinical course of primary multiple malignant tumors of the gastrointestinal tract are discussed. Out of 25 cases of synchronous gastrointestinal malignancies, both stomach and large bowel tumors were found in 10 patients and simultaneous neoplasms in different segments of the large bowel--in 15. In the latter group, radical surgery was performed in 13 patients. Out of 54 cases of metachronous cancer, 28 revealed combinations of stomach and large bowel tumors, while in 26 cases metachronous tumors appeared in succession in different segments of the large bowel. Synchronous single and multiple polyps of the large bowel were detected in 19 out of 54 patients. Radical surgery was carried out in 33 and palliative surgery--in 6 patients.