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PubMed1998

Fas ligand expression in primary colon adenocarcinomas: evidence that the Fas counterattack is a prevalent mechanism of immune evasion in human colon cancer.

Fas ligand (FasL) kills sensitive Fas receptor (FasR)-bearing cells by inducing apoptosis. FasL expressed by non-lymphoid cells within the eye and the testis mediates immune privilege by inducing apoptosis of Fas-sensitive infiltrating pro-inflammatory immune effector cells. It has previously been demonstrated by the present authors that the colon cancer cell SW620 expresses FasL and can kill lymphoid cells by Fas-mediated apoptosis in vitro. This 'Fas counterattack' was subsequently confirmed by others as a potential mechanism of immune privilege in various malignancies. The aim of the present study was to ascertain the prevalence of FasL expression in human colon cancer and to confirm that neoplastic colonic epithelial cells express FasL in vivo. The study of FasL expression by colon cancer cell lines was extended: it was shown that seven of eight colon adenocarcinoma cell lines expressed FasL mRNA, using reverse transcription-polymerase chain reaction (RT-PCR). Prevalent expression of FasL was confirmed in vivo: all the resected colonic tumours examined (31/31) were found to express FasL. In the tumours, FasL were co-localized to neoplastic colonic epithelial cells, using immunohistochemistry and in situ hybridization, respectively. FasL expression was independent of Dukes' stage, suggesting that it may occur throughout colon cancer progression. These results suggest that FasL is a common mediation of immune privilege in colon cancer.

Adenocarcinoma↗
PubMed2004

"Pouch colon patch graft"--an alternative treatment for congenital short colon.

A patch graft of the pouch colon over the pulled-through ileum in a patient with long-length pouch colon (in whom the entire colon was replaced by a pouch that communicated with the urinary bladder) was tried with good results for the first time. At follow-up the patient was found to have normal bowel patterns and weight gain. Though colon patch grafts have been widely used in patients with total colonic aganglionosis, they have not been tried for the short colon. The authors discuss the clinical setting in which the procedure may prove useful in patients with pouch colon and why these patch grafts may yield comparable or even better results in patients with pouch colon compared with those with total colonic aganglionosis.

Anastomosis, Surgical↗
PubMed1994

Effect of platelet-activating factor and its antagonists on colonic dysmotility and tissue levels of colonic neuropeptides.

We investigated whether platelet-activating factor (PAF) alters colonic tissue levels of substance P and vasoactive intestinal peptide (VIP), two neuropeptides that regulate colonic motility. Left colons were harvested from NZ White Rabbits and underwent vascular perfusion via the inferior mesenteric artery. Strain gauge transducers were sewn onto the serosal surface of the colon to evaluate colonic motility. Colons were perfused with either buffered saline alone or with 5.0 x 10(-5) M PAF. PAF administration increased tissue VIP and substance P levels and decreased the force of colonic contractions. Pretreatment with WEB-2170 or alprazolam decreased concentrations of both tissue neuropeptides, and decreased the force of colonic contractions and minute motility index. These results suggest that both VIP and substance P are stimulated by PAF and may participate in colonic dysmotility during inflammatory states.

Alprazolam↗
PubMed1983

Patterns of prostaglandin synthesis and degradation in isolated superficial and proliferative colonic epithelial cells compared to residual colon.

Prostaglandin (PG) synthesis and degradation were examined in different regions (epithelial versus non-epithelial structures) of the rat distal colon by both HPLC analysis of [14C] arachidonate (AA) metabolites and by specific radioimmunoassays. Intact isolated colonic epithelial cells synthesized mainly PGF2 alpha and TXA2, as monitored from the formation of its stable degradation product TXB2 (PGF2 alpha greater than TXB2 greater than 6-keto-PGF1 alpha, the stable degradation product of PGI2 = PGD2 = PGE2 = 13,14-dihydro-15-keto-PGF2 alpha). The profile of PG products of isolated surface epithelial cells was identical to that of proliferative epithelial cells. However, generation of PGs by surface epithelium was 2 to 3-fold higher than by proliferative cells both basally and in the presence of a maximal stimulating concentration (0.1 mM) of AA. The latter implied a greater synthetic capacity of surface epithelium, rather than differences due to endogenous AA availability. The major sites of PG synthesis in colon clearly resided in submucosal structures; the residual colon devoid of epithelial cells accounted for at least 99% of the total PGs produced by intact distal colon. The profile of AA metabolites formed by submucosal structures also differed markedly from that of the epithelium. The dominant submucosal product was PGE2. PGE2 and its degradation product 13,14-dihydro-15-keto-PGE2 accounted for 63% of the PG products formed by submucosal structures (PGE2 much greater than PGD2 greater than 13,14-dihydro-15-keto-PGE2 greater than PGF2 alpha = TXB2 = 6-keto-PGF1 alpha greater than 13,14-dihydro-15-keto-PGF2 alpha). By contrast, epithelial cells, and particularly surface epithelium, contributed disproportionately to the PG degradative capacity of colon, as assessed from the metabolism of either PGE2 or PGF2 alpha. When expressed as a percentage, epithelial cells accounted for 71% of total colonic PGE2 degradative capacity but only 23% of total colonic protein. Approximately 15% of [3H] PGE2 added to the serosal side of everted colonic loops crossed to the mucosal side intact. Thus, at least a portion of the PGE2 formed in the submucosa reaches, and thereby can potentially influence functions of the epithelium.

Animals↗
PubMed1986

Profiles of eicosanoid production by superficial and proliferative colonic epithelial cells and sub-epithelial colonic tissue.

The profile of cyclooxygenase and lipoxygenase products in normal rat colonic epithelium and subepithelium was examined. Colons were thoroughly perfused to eliminate contamination with blood. Two preparations of colonic epithelium were employed. The first consisted of intact colonic crypts and epithelial sheets. The second yielded single cell suspensions of superficial versus proliferative epithelial cells. Lipoxygenase product formation by colonic epithelium as measured by hydroxyeicosatetraenoic acid (HETE) and leukotriene B4 (LTB4) production (5-HETE greater than 12-HETE greater than 15-HETE greater than LTB4) accounted for 58% of the total colonic production of these moieties, whereas epithelium accounted for only 20% of total colonic protein. By contrast, prostaglandin (PG) E2 and PGF2 alpha production occurred predominantly (greater than 97%) in the subepithelial layers. The present studies also demonstrate markedly higher levels of accumulation of lipoxygenase products in proliferative versus superficial epithelial cells, whereas prostaglandin accumulation was greater in superficial cells. Previous studies have supported a role for lipoxygenase and cyclooxygenase products in the control of colonic secretion, inflammatory cell infiltration and proliferative activity. The present results raise the possibility that the striking differences in the sites of production of these products within the colon has functional implications.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗
PubMed1987

Is preserving the entire aganglionic colon reasonable in the surgical treatment of total colonic aganglionosis?

Clinical reports describe an increased incidence of severe enterocolitis in infants with total colonic aganglionosis (TCA) following the Martin extended Duhamel procedure using the entire aganglionic colon. This study evaluates the efficacy of this procedure in an experimental model of TCA in comparison with an antimesenteric aganglionic colon patch in rats. TCA was produced by serosal application of 0.1% benzalkonium chloride in 18 Sprague-Dawley rats (250 g). Five additional rats served as operated controls. Ileoanal pull-through was performed in 18 TCA rats, in conjunction with the Martin extended Duhamel procedure using the entire colon in six rats, with an aganglionic colon patch in nine (using the right [3 rats], transverse [3 rats] and left [3 rats] colon), and without other procedures in three rats. Animals were evaluated for survival, weight change, food intake, stool consistency and volume, barium enema, complete blood cell count (CBC), total protein, and serum electrolytes at 4 and 12 weeks. Survival was 83% (5/6) rats with the Martin procedure, 100% in the nine rats with various colon patches, zero in three rats with ileoanal pull-through alone, and 100% in controls. Rats with the Martin procedure gained 2.2 +/- 3.27% of preoperative weight, while controls gained 11.2 +/- 0.52% at 4 weeks. All other rats showed an early weight loss. At 12 weeks, right and transverse colon patched rats had weight gain. Blood count and laboratory studies were similar in each group. Barium enema showed rapid transit in rats with ileoanal pull-through, and slower transit in rats with colon patches or the Martin procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1999

Endoluminal pulse oximetry of the sigmoid colon and the monitoring of the colonic circulation.

Colonic ischaemia is a frequently observed serious complication following abdominal aortic reconstruction. For adequate treatment of this disorder, early diagnosis and resection of the diseased colon is essential. The purpose of this study was to evaluate a new method, based on pulse oximetry, to detect colonic ischaemia at an early preclinical stage. During a 7-year period (1989-1995) colonoscopy and pulse oximetry were performed in all patients at risk of colonic ischaemia: complicated acute or elective aortic reconstructions, colostomies with superficial necrosis and in patients who underwent uncomplicated aortic reconstruction and non-ischaemic colonic problems (n = 90). The sensitivity, specificity and positive predictive values, and negative predictive value, were calculated. All patients, except four for whom an acute relaparotomy was necessary, subsequently underwent colonoscopy combined with endoluminal pulse oximetry. Of the 90 patients, 30 had colonic ischaemia according to endoscopy (n = 26) or relaparotomy (n = 4), and in 33 patients the absence of pulsatile signal was detected by means of pulse oximetry. Thus, in three patients, pulse oximetry was falsely positive for colonic ischaemia. The calculated sensitivity and specificity of pulse oximetry were 100 and 95%, respectively. In comparison to other methods used for early detection of colonic ischaemia, pulse oximetry appears to be a promising method for the evaluation and monitoring of colonic ischaemia because it is non-invasive and easy to apply with a high sensitivity and specificity.

Adult↗
PubMed2006

Evaluation of the PillCam Colon capsule in the detection of colonic pathology: results of the first multicenter, prospective, comparative study.

BACKGROUND AND STUDY AIMS: Population-based screening for colorectal cancer is widely recommended, with conventional colonoscopy considered to be the preferred diagnostic modality. However, compliance with screening colonoscopy is low and manpower capacity is limited. Capsule endoscopy might therefore represent a desirable alternative strategy. PATIENTS AND METHODS: The PillCam Colon capsule endoscope was prospectively tested in a multicenter setting. The indications for endoscopy in the enrolled patients included colorectal cancer screening (43 %), postpolypectomy surveillance (26 %), and lower gastrointestinal signs and symptoms (31 %). Study subjects underwent colon preparation and then ingested the capsule on the morning of the examination, with conventional colonoscopy being performed the same day. The PillCam Colon capsule findings were reviewed by three experts in capsule endoscopy who were blinded to the conventional colonoscopy findings. RESULTS: A total of 91 subjects were enrolled in three Israeli centers (55 men, 36 women; mean age 57), and the results were evaluable in 84 cases. The capsule was excreted within 10 hours in 74 % of the patients and reached the rectosigmoid colon in the other 16 %. Of the 84 evaluable patients, 20 (24 %) had significant findings, defined as at least one polyp of 6 mm or more in size or three or more polyps of any size: 14/20 (70 %) were identified with the capsule and 16/20 (80 %) were identified by conventional colonoscopy. Polyps of any size were found in 45 patients, 34/45 (76 %) found by the capsule and 36/45 (80 %) by conventional colonoscopy. In comparison with conventional colonoscopy, false-positive findings on PillCam Colon capsule examination were recorded in 15/45 cases (33 %). There were no adverse events related to the capsule endoscopy. CONCLUSIONS: PillCam Colon capsule endoscopy appears to be a promising new modality for colonic evaluation. Further improvements in the procedure will probably increase capsule examination completion and polyp detection rates. Additional studies are needed to evaluate the accuracy of PillCam Colon endoscopy in other patient populations with different prevalence levels of colonic disease.

Adolescent↗
PubMed1985

Effect of added dietary calcium on colonic epithelial-cell proliferation in subjects at high risk for familial colonic cancer.

We studied the frequency and distribution of proliferating epithelial cells lining colonic crypts in 10 subjects at high risk for familial colonic cancer, before and after oral supplementation of their conventional diets with 1.25 g of calcium as calcium carbonate. Patterns of cell proliferation were defined by dividing the colonic crypt into longitudinal compartments and comparing the numbers and fractions of tritiated thymidine--labeled epithelial cells in the various compartments. Before dietary supplementation with calcium, the profile of proliferating epithelial cells in the colonic crypts was comparable to that previously observed in subjects who had had familial colonic cancer. Two to three months after supplementation had been started, proliferation was significantly reduced and the profile of the colonic crypts approached that previously observed in subjects at low risk for colonic cancer. Our findings indicate that oral calcium supplementation induces a more quiescent equilibrium in epithelial-cell proliferation in the colonic mucosa of subjects at high risk of colon cancer, similar to that observed in subjects at low risk.

Calcium, Dietary↗
PubMed2006

slc26a3 (dra)-deficient mice display chloride-losing diarrhea, enhanced colonic proliferation, and distinct up-regulation of ion transporters in the colon.

Mutations in the SLC26A3 (DRA (down-regulated in adenoma)) gene constitute the molecular etiology of congenital chloride-losing diarrhea in humans. To ascertain its role in intestinal physiology, gene targeting was used to prepare mice lacking slc26a3. slc26a3-deficient animals displayed postpartum lethality at low penetrance. Surviving dra-deficient mice exhibited high chloride content diarrhea, volume depletion, and growth retardation. In addition, the large intestinal loops were distended, with colonic mucosa exhibiting an aberrant growth pattern and the colonic crypt proliferative zone being greatly expanded in slc26a3-null mice. Apical membrane chloride/base exchange activity was sharply reduced, and luminal content was more acidic in slc26a3-null mouse colon. The epithelial cells in the colon displayed unique adaptive regulation of ion transporters; NHE3 expression was enhanced in the proximal and distal colon, whereas colonic H,K-ATPase and the epithelial sodium channel showed massive up-regulation in the distal colon. Plasma aldosterone was increased in slc26a3-null mice. We conclude that slc26a3 is the major apical chloride/base exchanger and is essential for the absorption of chloride in the colon. In addition, slc26a3 regulates colonic crypt proliferation. Deletion of slc26a3 results in chloride-rich diarrhea and is associated with compensatory adaptive up-regulation of ion-absorbing transporters.

Animals↗
PubMed2002

Aberrant crypt foci and colon cancer: comparison between a short- and medium-term bioassay for colon carcinogenesis using dimethylhydrazine in Wistar rats.

Aberrant crypt foci (ACF) in the colon of carcinogen-treated rodents are considered to be the earliest hallmark of colon carcinogenesis. In the present study the relationship between a short-term (4 weeks) and medium-term (30 weeks) assay was assessed in a model of colon carcinogenesis induced by dimethylhydrazine (DMH) in the rat. Six-week-old male Wistar rats were given subcutaneous injections of DMH (40 mg/kg) twice a week for 2 weeks and killed at the end of the 4th or 30th week. ACF were scored for number, distribution pattern along the colon and crypt multiplicity in 0.1% methylene-blue whole-mount preparations. ACF were distinguished from normal crypts by their larger size and elliptical shape. The incidence, distribution and morphology of colon tumors were recorded. The majority of ACF were present in the middle and distal colon of DMH-treated rats and their number increased with time. By the 4th week, 91.5% ACF were composed of one or two crypts and 8.5% had three or more crypts, while by the 30th week 46.9% ACF had three or more crypts. Thus, a progression of ACF consisting of multiple crypts was observed from the 4th to the 30th week. Nine well-differentiated adenocarcinomas were found in 10 rats by the 30th week. Seven tumors were located in the distal colon and two in the middle colon. No tumor was found in the proximal colon. The present data indicate that induction of ACF by DMH in the short-term (4 weeks) assay was correlated with development of well-differentiated adenocarcinomas in the medium-term (30 weeks) assay.

Adenocarcinoma↗
PubMedDate not supplied

The effect of an oral administration of Lactobacillus casei strain shirota on azoxymethane-induced colonic aberrant crypt foci and colon cancer in the rat.

The preventive effect of oral administration of viable Lactobacillus casei strain Shirota (LcS) on azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) and colon cancers in the rat was investigated. The study consisted of two experiments; in a short-term experiment (Exp-I), the inhibitory effect of 8- and 12-week treatments with LcS. Forty rats each received weekly a subcutaneous injection of AOM at a dose of 15 mg/kg of body weight for 5 weeks. Eight and twelve weeks after the start of the carcinogen treatment, each subgroup of rats were sacrificed, and the colon and the mesenteric lymph nodes (MLN) were removed. The number of ACFs and the surface marker of lymphocytes derived from the MLN were investigated. The large ACF (those comprising four or more aberrant crypts per focus) had significantly decreased in the rats which had consumed the LcS diet. And oral administration of viable LcS significantly recovered CD8 positive lymphocytes to the levels in the control group. In a long-term experiment (Exp-II), 30 rats each received weekly a subcutaneous injection of AOM at a dose of 7. 4 mg/kg of body weight for 10 weeks. Twenty-five weeks after the start of the carcinogen treatment, each subgroup of rats were sacrificed, and the colon were removed. The number and incidence of colon cancers were investigated. The number of rats with colon cancers and the number of colon cancers per rat, were significantly decreased in the rats which had consumed the LcS diet. LcS inhibited chemically-induced colon carcinogenesis in the rat. CD8 positive T lymphocytes may play a key role in the preventive effect against colon carcinogenesis.

Administration, Oral↗
PubMed1992

Colonic screening prior to renal transplantation and its impact on post-transplant colonic complications.

Colonic complications after renal transplantation are uncommon but have a high mortality rate. Some have recommended colonic screening in patients over 50 years of age prior to transplantation to lessen the impact of colonic diverticular disease. We report our 9-year experience of colonic screening for diverticular disease in potential recipients over the age of 50 and compare these results to the overall colonic complication rate in the same time period. From 1981-1990, 1186 renal transplants in 1019 patients were performed, during which time all potential recipients over the age of 50 yr were required to undergo colon evaluation prior to transplantation. Twenty cases of diverticular disease were found with more than a quarter of the cases in patients with adult polycystic disease. All underwent renal transplantation without a pre-transplant colectomy, and none had post transplant symptomatic colon disease. During that same time period a total of 14 colonic complications requiring surgical intervention were encountered with a mortality rate of 40%. Acute diverticulitis occurred in 5 patients, all of whom were over 50 yr of age, on low-dose immunosuppression, and in most cases it occurred remotely after transplantation. Colonic dysplasia/neoplasia also occurred remotely after transplantation in 2 patients over the age of 50. Cytomegalovirus (CMV) colitis was the next most common complication, accounting for 3 cases. This complication, which occurred in younger patients, was associated with high-dose steroid immunosuppression and had a high mortality rate, in spite of surgical intervention.(ABSTRACT TRUNCATED AT 250 WORDS)

Colitis↗
PubMed1992

Isolation and characterization of a cDNA encoding the putative distal colon H+,K(+)-ATPase. Similarity of deduced amino acid sequence to gastric H+,K(+)-ATPase and Na+,K(+)-ATPase and mRNA expression in distal colon, kidney, and uterus.

A series of Northern blot hybridization experiments using probes derived from the rat gastric H+,K(+)-ATPase cDNA and the human ATP1AL1 gene revealed the presence of a 4.3-kilobase mRNA in colon that seemed likely to encode the distal colon H+,K(+)-ATPase, the enzyme responsible for K+ absorption in mammalian colon. A rat colon library was then screened using a probe from the ATP1AL1 gene, and cDNAs containing the entire coding sequence of a new P-type ATPase were isolated and characterized. The deduced polypeptide is 1036 amino acids in length and has an Mr of 114,842. The protein exhibits 63% amino acid identity to the gastric H+,K(+)-ATPase alpha-subunit and 63% identity to the three Na+,K(+)-ATPase alpha-subunit isoforms, consistent with the possibility that it is a K(+)-transporting ATPase. Northern blot analyses show that the 4.3-kilobase mRNA is expressed at high levels in distal colon; at much lower levels in proximal colon, kidney, and uterus; and at trace levels in heart and forestomach. The high mRNA levels in distal colon and the similarity of the colon pump to both gastric H+,K(+)- and Na+,K(+)-ATPases suggest that it is the distal colon H+,K(+)-ATPase. Furthermore, expression of its mRNA in kidney raises the possibility that the enzyme also corresponds to the H+,K(+)-ATPase that seems to play a role in K+ absorption and H+ secretion in the distal nephron.

Adenosine Triphosphatases↗
PubMed1989

A prospective study of clinically and endoscopically documented colonic ischemia in 100 patients undergoing aortic reconstructive surgery with aggressive colonic and direct pelvic revascularization, compared with historic controls.

Clinically and endoscopically proved ischemia of the colon complicates elective aortic reconstruction in 1% to 2% and 6% to 7% of cases, respectively. Operative mortality exceeds 60% when transmural infarction occurs. A prospective study of colonic ischemia was undertaken in 100 male patients (mean age, 62.4 +/- 7.9 years) undergoing operation for aortic aneurysms (58) or aortoiliac occlusive disease (42). Conventional aortic surgery was undertaken in 88 patients, and in 12 patients adjunctive procedures to enhance colonic perfusion were performed 14 times, including IMA reimplantation (8), direct bypass to the internal iliac artery (4), and anastomosis of an aortofemoral bypass limb to adjacent common iliac artery (2). Colonoscopy was performed within 24 to 48 hours of aortic reconstruction. Three patients had endoscopic evidence of colonic ischemia. Transmural infarction did not develop in any patient, and bowel resections or diverting colostomies were not necessary. Three patients died, none manifesting colonic ischemia. The 12% utilization of adjunctive procedures to enhance blood flow in the colon was substantially greater than the 4% frequency of an earlier experience from our institution in which nearly half of the 5.7% operative mortality was attributed to colonic infarction. Attention to factors contributing to ischemia of the colon, and more frequent adjunctive revascularization of the colon, may lessen this complication of aortic reconstructive surgery.

Angiography↗
PubMed2004

Colonic smooth muscle responses in patients with diverticular disease of the colon: effect of the NK2 receptor antagonist SR48968.

BACKGROUND: Little is known about the pathophysiology of diverticular disease. AIM: To compare passive and active stress and the response to carbachol of colonic smooth muscle specimens from patients with diverticular disease and patients with colon cancer. The effect of the NK2 receptor antagonist, SR48968, on electrically evoked contractions of circular muscle was also investigated. PATIENTS: Sigmoid colon segments were obtained from 16 patients (51-83 years) undergoing elective sigmoid resection for diverticular disease and 39 patients (50-88 years) undergoing left hemicolectomy for non-obstructive sigmoid colon cancer. METHODS: Isometric tension was measured on circular or longitudinal taenial muscle. Strips were stretched gradually to Lo (length allowing the development of optimal active tension with carbachol) and were also exposed to increasing carbachol concentrations. The effects of atropine, tetrodotoxin and SR48968 on electrically evoked (supramaximal strength, 0.3 ms, 0.1-10 Hz) contractions of circular strips from 8 patients with diverticular disease and 19 patients with colon cancer were also studied. RESULTS: Both passive and active stress in circular muscle strips obtained from patients with diverticular disease was higher than in patients with colon cancer (P < 0.05). Electrically evoked contractions were significantly reduced by atropine in all preparations and were virtually suppressed by combined SR48968 and atropine. Tetrodotoxin suppressed electrically evoked contractions only in patients with colon cancer, whereas a tetrodotoxin-resistant component was identified in patients with diverticular disease. CONCLUSIONS: The changes in both passive and active stress in specimens from patients with diverticular disease may reflect circular smooth muscle dysfunction. Acetylcholine and tachykinins are the main excitatory neurotransmitters mediating electrically evoked contractions in human sigmoid colon circular muscle.

Aged↗
PubMed2000

Expression of heparanase in normal, dysplastic, and neoplastic human colonic mucosa and stroma. Evidence for its role in colonic tumorigenesis.

The human heparanase gene, an endo-beta-glucuronidase that cleaves heparan sulfate at specific intrachain sites, has recently been cloned and shown to function in tumor progression and metastatic spread. Antisense digoxigenin-labeled heparanase RNA probe and monoclonal anti-human heparanase antibodies were used to examine the expression of the heparanase gene and protein in normal, dysplastic, and neoplastic human colonic mucosa. To our knowledge, this is the first systematic study of heparanase expression in human colon cancer. Both the heparanase gene and protein were expressed at early stages of neoplasia, already at the stage of adenoma, but were practically not detected in the adjacent normal-looking colon epithelium. Gradually increasing expression of heparanase was evident as the cells progressed from severe dysplasia through well-differentiated to poorly differentiated colon carcinoma. Deeply invading colon carcinoma cells showed the highest levels of the heparanase mRNA and protein associated with expression of both the gene and enzyme by adjacent desmoplastic stromal fibroblasts. A high expression was also found in colon carcinoma metastases to lung, liver, and lymph nodes, as well as in the accompanying stromal fibroblasts. Moreover, extracts derived from tumor tissue expressed much higher levels of the heparanase protein and activity as compared to the normal colon tissue. In all specimens, the heparanase gene and protein exhibited the same pattern of expression. These results suggest a role of heparanase in colon cancer progression and may have both prognostic and therapeutic applications.

Aged↗