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J M Jessup

Publications and source records attributed to J M Jessup.

At least 55 records · Page 3Linked to original sources
PubMed1994

Normal colonic epithelium adheres to carcinoembryonic antigen and type IV collagen.

BACKGROUND/AIMS: Human colorectal carcinoma cells bind to collagen and laminin in the basement membrane as well as to carcinoembryonic antigen (CEA) on neighboring cells. The purpose of this study was to determine whether normal colonic epithelial cells bind to CEA, collagen, or laminin. METHODS: Intact colonic crypts were isolated from normal mucosa in 13 specimens resected for colorectal carcinoma or colonic diverticulitis. Colonocytes were released from the crypts by treatment with collagenase and deoxyribonuclease and tested for adhesion to CEA, type IV collagen, and laminin in a solid-phase adhesion assay. RESULTS: Twelve percent to 25% of colonocytes in all specimens bound to CEA. Colonocytes from seven specimens also bound to type IV collagen, but none of the colonocyte preparations bound significantly to laminin. Monoclonal antibodies to CEA and to the hyaluronate receptor CD44 and enzymatic removal of membrane CEA blocked the adhesion of colonocytes to CEA. CONCLUSIONS: First, colonocytes use the same epitopes on CEA and CD44 as colorectal carcinoma cells to adhere to solid-phase CEA. Second, colonocytes bind to solid-phase CEA through CEA-to-CEA homophilic binding. Third, CEA and type IV collagen, but not laminin, are adhesion ligands for human colonocytes.

Antibodies↗
PubMed1994

Simulated microgravity does not alter epithelial cell adhesion to matrix and other molecules.

Microgravity has advantages for the cultivation of tissues with high fidelity; however, tissue formation requires cellular recognition and adhesion. We tested the hypothesis that simulated microgravity does not affect cell adhesion. Human colorectal carcinoma cells were cultured in the NASA Rotating Wall Vessel (RWV) under low shear stress with randomization of the gravity vector that simulates microgravity. After 6-7 days, cells were assayed for binding to various substrates and compared to cells grown in standard tissue culture flasks and static suspension cultures. The RWV cultures bound as well to basement membrane proteins and to CEA, an intercellular adhesion molecule, as control cultures did. Thus, microgravity does not alter epithelial cell adhesion and may be useful for tissue engineering.

Basement Membrane↗
PubMed1993

Localization of tumor-associated glycoprotein DF3 in normal, inflammatory, and neoplastic lesions of the colon.

BACKGROUND: The expression of DF3 was assessed by a monoclonal antibody in normal, inflammatory, and neoplastic conditions in the large bowel. METHODS: Using immunohistochemistry, expression was examined in formalin-fixed paraffin-embedded biopsy and resection samples of 19 normal colonic mucosal specimens, 49 inflammatory lesions, 34 adenomas, and 38 primary colonic adenocarcinomas. In addition, Western blots of normal colonic mucosa and adenocarcinoma were examined. RESULTS: DF3 expression was detected in 84% of the adenocarcinomas with coarse membrane staining, intense positivity of luminal secretions, and focal cytoplasmic and intracytoplasmic vacuole staining. Nine of 32 areas of transitional mucosa revealed reactivity along apical membranes in crypt cells. Five adenomas containing carcinoma revealed DF3 positivity in the malignant areas only, whereas the remaining 29 were negative. Staining was membrane, luminal, and intracytoplasmic. Two examples of active ulcerative colitis revealed focal reactivity along the apical membrane of crypt cells. No other areas of staining were noted, including 12 cases containing dysplasia. Four of 10 other inflammatory lesions also revealed similar membrane reactivity in crypt cells. Normal colonic mucosa was nonreactive. Examples of normal colonic mucosa were negative for DF3 by Western blot analysis, whereas two carcinoma samples that reacted immunohistochemically were positive. CONCLUSIONS: DF3 is not detectable in normal colonic tissues. It is expressed focally and predominantly along the apical membrane of crypt cells in some inflammatory lesions and in the transitional mucosa of primary adenocarcinomas. Most adenocarcinomas of the colon and adenomas with foci of invasive carcinoma demonstrate reactivity in the cytoplasm and luminal secretions.

Adenocarcinoma↗
PubMed1993

Adhesion to carcinoembryonic antigen by human colorectal carcinoma cells involves at least two epitopes.

Carcinoembryonic antigen (CEA) may be involved in both cell-cell and cell-substrate adhesion. Our purpose was to determine whether epitopes involved in the homophilic binding of human colorectal carcinoma cells to CEA participated in adhesion to basement membrane proteins. Three human colorectal adenocarcinoma cell lines and one CHO cell line transfected with CEA cDNA were tested in a solid-phase adhesion assay. The 2 CEA-expressing carcinoma cell lines (KM-12c and CCL 188) and the transfectant, but not the parental CHO line, bound to CEA. The CEA-non-producing carcinoma line (Clone A) did not bind to CEA. All colorectal carcinoma cell lines, the transfectant and the parental CHO line bound to laminin, while the colorectal carcinoma lines bound to type-IV collagen. MAbs to epitopes on CEA that cross-react with non-specific cross-reacting antigen (NCA) inhibited adhesion of CEA-expressing cells to CEA. MAbs to non-cross-reactive epitopes of CEA did not block adhesion to CEA. When the inhibitory anti-CEA antibodies were compared in a competitive radioimmunoassay, 2 distinct epitopes were identified. Epitope I is in the N-terminal domain and defined by MAbs MN3, T84.1 and C110, whereas epitope II is located in the repeating loop domains and is recognized by antibodies MN15, PR3B10 and NP1. None of the antibodies to epitope I or II blocked adhesion by KM-12c or CCL 188 cells to laminin or type-IV collagen. Thus, at least 2 different regions on CEA participate in adhesion to CEA but not to collagen or laminin by CEA-expressing human colorectal carcinoma cells.

Adenocarcinoma↗
PubMed1993

Neoadjuvant therapy for unresectable pancreatic adenocarcinoma.

The purposes of this study were to determine whether continuous infusion of fluorouracil combined with external-beam radiation therapy improved the resectability and survival of patients with pancreatic carcinoma. Sixteen patients with unresectable disease confined to the pancreas and celiac nodes were treated, and their outcome was compared with that of 24 patients with potentially resectable disease who were treated concurrently. The neoadjuvant therapy was completed with acceptably few toxic effects but with only a minor decrease in tumor size. Two patients underwent resection and remained free of disease 20 and 22.5 months later. However, the median survival of the entire neoadjuvant group was 8 months. All 24 patients with potentially resectable carcinoma underwent surgical exploration. Fifteen of the 24 patients underwent resection and survived a median of 12.5 months. Neoadjuvant chemoradiation may have improved outcome and resectability for two (12.5%) of 16 patients with unresectable pancreatic carcinoma, but more effective therapy options must be developed to improve outcome.

Adenocarcinoma↗
PubMed1993

Prospects for use of microgravity-based bioreactors to study three-dimensional host-tumor interactions in human neoplasia.

Microgravity offers unique advantages for the cultivation of mammalian tissues because the lack of gravity-induced sedimentation supports three-dimensional growth in batch culture in aqueous medium. Bioreactors that simulate microgravity but operate in unit gravity provide conditions that permit human epithelial cells to grow to densities approaching 10(7) cells/ml on microcarriers in suspension, in masses up to 1 cm in diameter, and under conditions of low shear stress. While useful for many different applications in tissue culture, this culture system is especially useful for the analysis of the microenvironment in which host matrix and cells interact with infiltrating tumor cells. Growth in the microgravity-based bioreactor has supported morphological differentiation of human colon carcinoma cells when cultured with normal human stromal cells. Furthermore, these co-cultures produced factors that stimulated goblet cell production in normal colon cells in an in vivo bioassay. Early experiments also suggest that the microgravity environment will not alter the ability of epithelial cells to recognize and associate with each other and with constituents of basement membrane and extracellular matrix. These findings suggest that cells grown in bioreactors that simulate aspects of microgravity or under actual microgravity conditions will produce tissues and substances in sufficient quantity and at high enough concentration to promote characterization of molecules that control differentiation and neoplastic transformation.

Biotechnology↗
PubMed1993

The significance of carbonic anhydrase expression in human colorectal cancer.

BACKGROUND: Carbonic anhydrase isoenzymes I and II are present in normal colorectal mucosa. This study aimed to determine if carbonic anhydrase is present in colorectal cancer and what is its potential clinical significance. METHODS: The messenger RNA (mRNA) and protein expression of carbonic anhydrase isoenzyme I were analyzed in fresh specimens of colorectal adenocarcinoma by Northern and Western blots, respectively. The immunohistochemical expression was subsequently studied in a larger number of formalin-fixed surgical specimens. RESULTS: All of 30 normal colon samples had a strong RNA hybridization signal. Only 4 of 39 paired colorectal cancer and none of 9 normal liver samples had detectable levels of carbonic anhydrase mRNA. Isoenzyme I protein expression showed similar results. In a separate group of patients, immunohistochemical studies showed that 16 of 96 colorectal tumors had positive staining cells. All positive tumors were well or moderately differentiated carcinomas (P < 0.05). When analyzed retrospectively, immunoreactive cases were more likely to be in a group with a good outcome (P < 0.01) and to lack vascular invasion (P < 0.01) than negative cases. CONCLUSIONS: The majority of colorectal cancers do not express carbonic anhydrase isoenzyme I. The presence of any isoenzyme I-positive immunoreactive cancer cells may be associated with a more favorable outcome in colorectal cancer.

Adult↗
PubMed1993

CD44 participates in the adhesion of human colorectal carcinoma cells to laminin and type IV collagen.

CD44 is a cellular adhesion molecule expressed in many different types of cells that may be a receptor for hyaluronic acid, laminin, collagen or fibronectin. In this study, we determined whether CD44 participated in the adhesion of three human colorectal carcinoma cell lines (KM-12c, CCL 188 and MIP-101) to laminin, collagen and hyaluronic acid. All lines were positive for the epithelial form of CD44 (CD44E) with a molecular weight of approximately 160 kD. All of them bound significantly to laminin and type IV collagen but not to hyaluronic acid in a solid phase adhesion assay. Three monoclonal antibodies to CD44 (Hermes 1, Hermes 3 and J173) significantly blocked the binding of colorectal carcinoma lines to laminin and collagen whereas another antibody to CD44 (50B4) bound to cells but did not inhibit adhesion. Only Hermes 1 completely abolished the binding to hyaluronic acid by a human B lymphoblastoid cell line, JY, that expressed the 90 kD haematopoietic form of CD44. Soluble hyaluronate inhibited the adhesion of JY cells to solid phase hyaluronate but did not inhibit adhesion to laminin and collagen by the colorectal carcinoma lines. Thus, (a) CD44E participates in the adhesion of colorectal carcinoma cells to laminin and type IV collagen and (b) the binding site for laminin and collagen on CD44E is different from the site for hyaluronic acid.

Antibodies, Monoclonal↗
PubMed1993

Carcinoembryonic antigen: enhancement of liver colonisation through retention of human colorectal carcinoma cells.

Carcinoembryonic antigen (CEA) is an oncofetal antigen whose function in the progression of colorectal carcinoma remains unclear although recent studies suggest it participates in homotypic cellular adhesion. We have previously shown that 40 micrograms of CEA injected intravenously into athymic nude mice enhances experimental metastasis in liver and lung by two human colorectal carcinoma cell lines that are injected intrasplenically 30 min later. The metastatic potential of another three moderately to highly metastatic colorectal carcinoma cell lines and of one weakly metastatic line has now been analysed in this model. CEA pretreatment only enhanced colony formation by cell lines that were weakly metastatic in untreated nude mice; it did not affect experimental metastasis by highly metastatic lines. CEA pretreatment enhanced the retention of 125I Idudr-labelled weakly metastatic tumour cells within the liver and lungs 4 h after intrasplenic injection but not the retention of highly metastatic tumour cells or inert latex beads. A significant correlation existed between the formation of experimental metastases and the early retention of tumour cells within the liver after intrasplenic injection. Aggregation did not appear to be important for retention in liver because CEA did not aggregate colorectal carcinoma cells in vitro. Also CEA did not alter natural host effector cell function in a cytolysis assay in vitro. We suggest that CEA facilitates liver colonisation by three of eight human colorectal carcinomas in athymic nude mice by increasing the hepatic retention of tumour cells. The potential mechanisms by which CEA may increase the retention of tumour cells in the liver are discussed.

Animals↗
PubMed1993

The prognostic significance of proliferating cell nuclear antigen in clinical gastric cancer.

BACKGROUND: Proliferating cell nuclear antigen (PCNA) is an intranuclear protein that is closely linked to the cell cycle. This antigen can be detected in formalin-fixed specimens. We studied the expression of PCNA in primary gastric cancer to identify its significance as a prognostic factor. METHODS: The avidin-biotin-peroxidase complex method was used for PCNA staining in sections from 138 patients with primary gastric cancer. All sections were formalin fixed and paraffin embedded. Two different sections were examined in each case. RESULTS: The PCNA labeling index (PCNA-positive cells/1000 cells x 100) varied from 7.0% to 59.7%. There were significant differences in tumor size, morphologic type, depth of tumor invasion, lymphatic permeation, vascular permeation, and lymph node metastasis between the high (> or = 33.4) and low (< 33.4) PCNA labeling index groups. The 5-year survival rates of the high and low PCNA labeling index groups were 5.8% and 66.2%, respectively, a significant difference (p < 0.001). Multivariate analysis showed that the PCNA labeling index was an independent prognostic factor for gastric cancer. CONCLUSIONS: Because PCNA immunostaining can be done in routine formalin-fixed paraffin-embedded sections, this could be a powerful tool for providing information about the prognosis of patients with gastric cancer.

Antigens, Neoplasm↗
PubMed1993

Prothymosin-alpha mRNA expression correlates with that of c-myc in human colon cancer.

Prothymosin alpha (PT-alpha) is a nuclear protein involved in cell proliferation. Transcription of PT-alpha has been reported to be regulated by the c-myc gene in vitro. We identified PT-alpha as being overexpressed in a human colon cancer minus normal mucosa subtraction cDNA library. Northern blot (messenger RNA) analysis showed that both PT-alpha and c-myc genes were overexpressed in human colorectal cancers compared with adjacent normal tissues. Immunohistochemical studies for PT-alpha and c-myc supported these findings. There was no correlation between PT-alpha or c-myc messenger RNA expression and Dukes' stage of colorectal cancer; or between either of these two and actin messenger RNA expression. There was, however, a significant correlation between the PT-alpha expression and c-myc expression (P < 0.001). These findings support the hypothesis that PT-alpha gene transcription may be associated with, and possibly under the control of, the c-myc gene in human colorectal cancers.

Blotting, Northern↗
PubMed1992

Morphologic differentiation of colon carcinoma cell lines HT-29 and HT-29KM in rotating-wall vessels.

A new low shear stress microcarrier culture system has been developed at NASA's Johnson Space Center that permits three-dimensional tissue culture. Two established human colon adenocarcinoma cell lines, HT-29, an undifferentiated, and HT-29KM, a stable, moderately differentiated subline of HT-29, were grown in new tissue culture bioreactors called Rotating-Wall Vessels (RWVs). RWVs are used in conjunction with multicellular cocultivation to develop a unique in vitro tissue modeling system. Cells were cultivated on Cytodex-3 microcarrier beads, with and without mixed normal human colonic fibroblasts, which served as the mesenchymal layer. Culture of the tumor lines in the absence of fibroblasts produced spheroidlike growth and minimal differentiation. In contrast, when tumor lines were co-cultivated with normal colonic fibroblasts, initial growth was confined to the fibroblast population until the microcarriers were covered. The tumor cells then commenced proliferation at an accelerated rate, organizing themselves into three-dimensional tissue masses that achieved 1.0- to 1.5-cm diameters. The masses displayed glandular structures, apical and internal glandular microvilli, tight intercellular junctions, desmosomes, cellular polarity, sinusoid development, internalized mucin, and structural organization akin to normal colon crypt development. Differentiated samples were subjected to transmission and scanning electron microscopy and histologic analysis, revealing embryoniclike mesenchymal cells lining the areas around the growth matrices. Necrosis was minimal throughout the tissue masses. These data suggest that the RWV affords a new model for investigation and isolation of growth, regulatory, and structural processes within neoplastic and normal tissue.

Adenocarcinoma↗
PubMed1991

Resectable gastric carcinoma. An evaluation of preoperative and postoperative chemotherapy.

Patients with locoregional gastric carcinoma often die because of the low rates of curative resection and frequent appearance of distant metastases (mainly peritoneal and hepatic). To evaluate the feasibility of preoperative and postoperative chemotherapy, 25 consecutive previously untreated patients with potentially resectable locoregional gastric carcinoma received two preoperative and three postoperative courses of etoposide, 5-fluorouracil, and cisplatin (EFP). Ninety-eight courses (median, five courses; range, two to five courses) were administered. Six patients had major responses to EFP. Eighteen patients (72%) had curative resections, and three specimens (12%) contained only microscopic carcinoma. At a median follow-up of 25 months, the median survival of 25 patients was 15 months (range, 4 to 32+ months). Peritoneal carcinomatosis was the most common indication of failure. One patient died of postoperative complications, but there were no deaths due to chemotherapy. EFP-induced toxic reactions were moderate. Preoperative and postoperative chemotherapy for locoregional gastric carcinoma is feasible, and additional studies to develop regimens that could result in 5% to 10% complete pathologic responses may be warranted.

Adenocarcinoma↗
PubMed1991

A pilot study of sphincter-sparing management of adenocarcinoma of the rectum.

After analysis of 26 prospectively accrued patients with distal rectal adenocarcinomas who underwent sphincter preservation treatment, we have concluded that tumors that invade only the submucosa can safely be treated with surgery alone and that tumors that invade the muscularis or further can be safely treated with surgery combined with chemoradiotherapy. None of the patients had either local or distant recurrence, with a median follow-up of 21 months. All patients have been fully continent. The results, although preliminary, imply that resection of distal rectal adenocarcinoma with sphincter preservation, and adjuvant therapy when appropriate, have achieved local and distant control equal to the conventional Miles' abdominoperineal resection, but without the need for a permanent colostomy.

Adenocarcinoma↗
PubMed1991

Predominant expression of mRNA coding for nonspecific cross-reacting antigen in colorectal carcinomas.

We have analyzed specific transcripts of the carcinoembryonic antigen (CEA) gene family expressed in 32 colorectal carcinomas (CRCs) and when possible, their corresponding adjacent (less than 1 cm) and distant (greater than 10 cm) mucosas. From 1 of the 32 patients, we obtained a corresponding tubulovillous adenoma. From 1 additional patient a Crohn's disease sample was also evaluated. CEA mRNA was detectable by northern blot hybridization in 97% of the CRCs examined. Of these, 41% expressed this transcript at higher levels in the tumor than in the corresponding distant mucosa. Nonspecific cross-reacting antigen (NCA) is another member of the CEA gene family. The NCA mRNA was detectable in 87% of the CRCs examined, with 92% of these expressing the NCA mRNA at higher levels than the tubulovillous adenoma and the specimen from Crohn's colitis, whereas CEA was easily detected. Our findings demonstrate that NCA mRNA is more consistently overexpressed in colon carcinoma relative to distant mucosa than CEA mRNA.

Adult↗