Patterns of gene expression that characterize the colonic mucosa in patients at genetic risk for colonic cancer

We have used a computer-driven scanning and image-processing system to identify a panel of 30 cDNA clones whose pattern of expression in individual biopsy specimens distinguishes the flat, normal-appearing colonic mucosa of patients in two genetic groups at high risk for development of colorectal cancer from that of normal colonic mucosa in low-risk individuals. The two high-risk groups, familial adenomatous polyposis and hereditary nonpolyposis colon cancer, are indistinguishable based on the pattern of expression of the 30 selected clones. This suggests that the extensive pleiotropic effects of the inherited loci, which may play an important role in the mechanism of increased risk and early onset of the disease, are similar in these populations.

Correlations between rectal mucosa cell proliferation and the clinical and pathological features of nonfamilial neoplasia of the large intestine

An in vitro study of proliferative activity as shown by immunohistochemical detection of the uptake of bromodeoxyuridine was run on rectal biopsies from 400 patients with nonfamilial large bowel neoplasia: 200 adenoma; 150 adenocarcinoma; 50 adenoma plus adenocarcinoma. The controls were 400 subjects with negative personal and family histories of colorectal neoplasia. The number and height distribution of bromodeoxyuridine positive cells were determined by dividing the crypt into five longitudinal compartments. The total labeling index and the labeling index of each compartment were higher in all three groups compared with the controls. In subjects with adenoma, total labeling index and labeling index values were correlated with tumor size and decreased in function of the duration of the polyp-free colon state. The major zone of DNA synthesis had shifted to the intermediate and surface crypt compartments in all three groups. This stage II abnormality was more marked in adenoma patients with a high degree of dysplasia and in those with adenoma plus adenocarcinoma. Hyperproliferation and the proliferative compartment shift are cytokinetic abnormalities that coexist in the flat rectal mucosa of patients with colorectal neoplasia. Nonetheless, they are independent, controlled by different factors, and are expressions of different biological aspects of large bowel carcinogenesis.

Lectin soybean agglutinin: measurements in colonic epithelial cells of human subjects following supplemental dietary calcium

A biomarker of cell differentiation was analyzed in normal and abnormal colonic epithelial cells. Soybean agglutinin (SBA) lectin which binds to specific carbohydrate residues was studied in normal human colonic epithelial cells, in epithelial cells in transitional colonic mucosa adjacent to carcinomas, and in colonic carcinomas. Findings revealed that increased SBA binding occurred maximally in normal, well-differentiated colonic epithelial cells, and least in colonic carcinomas. Further quantitation of SBA lectin binding also was carried out before and after supplemental dietary calcium. Findings revealed that in subjects whose colonic crypt biopsies had normal SBA lectin binding before calcium supplementation, SBA remained unchanged after calcium supplementation. However, in subjects whose biopsies initially had reduced SBA binding, the SBA increased after calcium and became more characteristic of that observed in normal colonic epithelium. In subjects receiving calcium for less than 3 months, the increased SBA was not statistically significant; but when subjects received calcium for durations of 3 months or longer SBA lectin binding was significantly increased, changing towards that observed in normal mucosa containing greater numbers of well-differentiated colonic epithelial cells.

AE1 cytokeratin reaction patterns in different differentiation states of squamous cell carcinoma of the esophagus

Anticytokeratin antibody AE1 was studied immunohistochemically in 56 surgical specimens of esophageal carcinoma. Relationships between morphologic characteristics and AE1 reaction patterns were analyzed in carcinomas and adjacent epithelium. Infiltrating carcinomas had three types of AE1 patterns that paralleled degrees of differentiation. Type 1 pattern was present in well-differentiated carcinomas characterized by cytoplasmic staining of polyhedral cells. Types 2 and 3 were seen in poorly differentiated and undifferentiated carcinomas in different percentages, characterized by all cancer cells stained, with cellular membrane and cytoplasm stained or all unstained, respectively. In normal esophageal epithelium, basal cells were the major population that was AE1 positive. In hyperplasia basal cells showed two kinds of changes, either reduced/lost AE1 staining accompanied by AE1 expression in spinous cells or retained/increased AE1 reactivity. In dysplasia and carcinoma in situ, abnormal cells had reaction patterns in which they lost or increased AE1 expression. Findings indicate that different degrees of differentiation of infiltrating esophageal carcinoma cells have differing expressions of cytokeratins and that monoclonal antibody AE1 can serve as a biomarker identifying early abnormalities in esophageal epithelial cells having increased predisposition to malignancy. Molecular mechanisms of AE1 cytokeratin expression in esophageal epithelium are also discussed.

Evaluating evaluation: assessment of the American Board of Internal Medicine Resident Evaluation Form

The American Board of Internal Medicine suggests use of a standard form to rate residents on nine dimensions (such as clinical judgment and overall clinical competence) on a scale of 1 to 9. The authors examined the psychometric evidence for reliability and validity of 1,039 ratings of 85 residents by 135 attendings in a single internal medicine residency program. Of these ratings, 95.6% were from 6 to 9. Factor analysis revealed that high correlations among the nine dimensions (r ranged from 0.72 to 0.92) resulted from a single global factor accounting for 86% of the variance. The study also examined whether the form reliably distinguishes among residents scoring between 6 and 9. Agreement among attendings rating the same individual was weak (average reliability = 0.64, by the method of James). The rating method fails to discriminate dimensions of clinical care and has low reliability for distinguishing among competent residents.

Labeling index and labeling distribution of cells in esophageal epithelium of individuals at increased risk for esophageal cancer in Huixian, China

The pattern of proliferation of epithelial cells in esophageal epithelium was studied by means of [3H]deoxythymidine labeling of esophageal epithelium in subjects from Huixian, Henan Province, China, a high-risk geographical region for esophageal cancer. Comparisons were made among patterns of cell proliferation observed in normal esophagus, in hyperplasia, in mild dysplasia, and in moderate dysplasia in a total of 118 subjects. The amount of cell proliferation observed was lowest in normal esophageal epithelium and increased progressively in subjects having hyperplasia, mild dysplasia, and moderate dysplasia. The location of proliferating cells was limited mainly to the base of the esophageal epithelium in normal esophagus, but expanded toward the surface of the esophageal lining in individuals with hyperplasia and dysplasia. The larger total numbers of proliferating cells in the esophageal epithelium and the progressive expansion of the proliferative compartment toward the epithelial surface found in hyperplasia and in dysplasia could both facilitate the screening of subjects for esophageal cancer risk and serve as intermediate biomarkers in prophylactic dietary or pharmacological intervention studies.

Injury induced by fatty acids or bile acid in isolated human colonocytes prevented by calcium

Measurement of the modulation of the growth fraction of isolated normal colonocytes from adult subjects in primary monolayer culture was used as a sensitive quantitative assay to evaluate toxic effects of several endogenous compounds found within the colon. This assay was used to study the role of CaCl2 in blocking cell injury. When added simultaneously with the injurious agent, 5-10 mM CaCl2 blocked the toxicity of physiological concentrations of deoxycholic acid, oleic acid, palmitic acid and linoleic acid.

Dietary calcium and chronic diseases

The Agricultural Revolution was almost certainly associated with a substantial decrease in human calcium intake. Calcium intakes typical of contemporary humans may well be inadequate for many individuals. Various slowly developing chronic disorders such as osteoporosis, hypertension, hyperlipidemia, and colon cancer may be induced or exaggerated by the current low level of dietary calcium intake in Western societies. We propose two hypotheses relating calcium intake to diverse diseases: first, the adaptation required to adjust to low intakes is inadequate to maintain critical components of cellular calcium regulation; second, the constant, forced adaptive response to low intake itself produces untoward consequences.

Colonic hyperplasia and hyperproliferation induced by a nutritional stress diet with four components of Western-style diet

We studied the effects of specific nutritional modifications on colonic epithelial cell proliferation in mice and rats. The nutritional stress diet developed for this study was based on the AIN (American Institute of Nutrition)-76A semisynthetic diet, modified to contain four suggested risk factors of the human Western-style diet: increased fat and phosphate and decreased calcium and vitamin D content. We fed diets to mice and rats for 12 weeks beginning at 3 weeks of age. Hyperplasia developed in both sigmoid and ascending colon of mice and rats with lengthening of colonic crypts. Hyperproliferation developed in the sigmoid colon of mice and rats, and in the ascending colon of rats, with increased [3H]thymidine-labeling of epithelial cells. Thus, in colonic mucosa, the nutritional stress diet, which included risk factors of a Western-style diet, induced changes that occur in carcinogen-induced rodent models and in humans who are at increased risk for colonic neoplasia.

Expression of mitochondrial cytochrome c oxidase in human colonic cell differentiation, transformation, and risk for colonic cancer

In a panel of eight cloned complementary DNA sequences whose level of expression characterize colon cells as transformed in vivo and in vitro, one which may also serve as a marker of risk in familial polyposis and familial colon cancer flat mucosa has been identified as mitochondrial cytochrome c oxidase subunit 3. Mean level of expression of cytochrome c oxidase subunit 3 decreases progressively in colon adenomas and carcinomas relative to normal mucosa in vivo, and returns to higher levels present in biopsies of normal mucosa when the HT29 human colonic adenocarcinoma cell line is induced to differentiate with sodium butyrate. Quantitation of cytochrome c oxidase subunit 3 DNA by dot blots indicated that these changes in expression were not associated with alterations in the number of mitochondrial genomes.

Primary care internal medicine: a challenging career choice for the 1990s

A career in primary care internal medicine can be challenging and rewarding, yet during the last decade fewer medical students have selected training in internal medicine. We wish to inform medical students, their advisors, and other physicians about the field of primary care internal medicine. We define the discipline, compare it with traditional internal medicine and with family practice, and describe features of strong primary care internal medicine training programs. We discuss common misconceptions and concerns about training programs and the career and give examples of career paths chosen by graduates of primary care programs. We encourage students to consider the option of primary care internal medicine when making career decisions and provide faculty advisors unfamiliar with primary care internal medicine training programs with a reference resource.

Heterogeneity in the response of familial polyposis epithelial cells and adenomas to increasing levels of calcium in vitro

A biomarker of increased risk for colon cancer is abnormally high proliferation of colonic epithelial cells. The authors developed an in vitro assay that measures the ability of human colonic epithelial cells that are in progressive stages of abnormal development to respond to direct application of calcium as the chloride in tissue culture medium. Incorporation of 3H-thymidine and autoradiography in situ was employed to measure the number of proliferating cells cultured at 0.1 mM CaCl2, the optimum level for growth, and 2.2 to 5 mM, both levels achievable in the colonic lumen. Abnormal cell proliferation was reduced in biopsies from 13 of 14 patients without familial polyposis but at increased risk for colon cancer because of previous colonic neoplasms or familial association; in cells from three of four asymptomatic individuals in familial polyposis families at risk for that disease; and in cells of three of ten patients symptomatic with familial polyposis. Growth of tubular adenoma cells from two of seven familial polyposis patients was also inhibited by calcium. Growth inhibition was not observed in more advanced colon tumors including eight adenomas, either villotubular or villous, and five carcinomas. These findings indicate heterogeneity within the familial polyposis phenotype for the normal cellular response to growth inhibition by calcium, and a further loss of response to calcium as these cells progress toward malignancy.

Hypersegmented neutrophils and vitamin B12 deficiency. Hypersegmentation in B12 deficiency

The sensitivities and specificities of the mean cell volume (MCV), the red cell distribution width (RDW), and blood smear hypersegmentation for B12 deficiency were reviewed in 515 patients whose B12 levels were determined. 61 patients had B12 levels less than 200 pg/ml. 43 patients were defined as B12 deficient (n = 13) or non-B12 deficient (n = 30). Hypersegmentation was more sensitive (91%) than MCV greater than 95 fl (62%) or RDW greater than 15% (54%) in detecting B12 deficiency. The MCV and the RDW should not be relied on when screening for B12 deficiency; examination of the blood smear for hypersegmentation is essential.

Reactivity of a human monoclonal antibody against carcinomas and other lesions of the colon

To identify tumor-associated antigens that may be immunogenic to man, human monoclonal antibodies (human mAb) were generated by fusing nonsecreting mouse myeloma cells with lymphocytes from regional mesenteric nodes of patients with adenocarcinomas of the colon. One IgG1 human mAb, designated as 14-31-10, was identified by its reactivity against human tumor xenografts. We have studied the reactivity of mAb 14-31-10 with formalin-fixed, paraffin-embedded specimens of human colon. A total of 86 cases were studied, including normal adult and fetal colons, adenocarcinomas of the colon, and a variety of colonic inflammatory diseases and preneoplastic lesions. Intense reactivity was found in 15 of 18 adenocarcinomas of the colon, but not in 10 specimens of normal adult or 4 specimens of fetal colonic mucosa. Interestingly, in four cases of carcinoma, reactivity was also observed in histologically normal mucosa situated 10 cm or more from the primary lesion. On the other hand, no staining was detected in any of the 16 inflammatory lesions. Of the 38 preneoplastic lesions, only 6 showed staining by the mAb: 1 of 5 benign tubular adenomatous polyps, 3 of 9 villous adenomas and tubovillous polyps, 1 of 5 specimens of ulcerative colitis and 1 of 19 specimens of familial polyposis. However, the intensity of staining was only moderate in those cases. Our data, therefore, suggest that the epitope identified by the human mAb 14-31-10 shows preferential expression in preneoplastic and neoplastic lesions of the colon, and in ostensibly normal mucosa at some distance from a primary colonic carcinoma. In all instances, the staining was cytoplasmic, suggesting a cytoplasmic or internal membrane location of the target antigen. This antigen appeared to be distinct from carcinoembryonic antigen, since staining by 14-31-10 was consistently different from that of a mouse monoclonal antibody to carcinoembryonic antigen in serial sections of the same specimens. The restricted reactivity of 14-31-10 suggests its potential application in immunohistochemistry. Moreover, the epitope identified by mAb 14-31-10 may be expressed during the progression of normal mucosa to neoplasia.

Decreased content of the 35 kDa cytoskeletal protein p35 in Friend erythroleukemia cells exposed to dimethyl sulfoxide and retinoic acid is associated with entrance into a quiescent substrate

1. The effect of all-trans-retinoic acid (RA) on cell cycle kinetics, RNA content, and expression of the 35 kDa cytoskeletal protein p35 in exponentially-growing Friend erythroleukemia (FL) cells was compared with the prototypic differentiation-inducer dimethylsulfoxide (DMSO). 2. Two G1 phase populations of RA-treated FL cells were identified: one with an intermediate RNA content (T-cells) similar to G1 cells in near-plateau-phase control cultures and the other with a very low RNA content (Q-cells) similar to DMSO-differentiated cells; although quiescent, RA-treated cells remained undifferentiated as evidenced by the absence of late-stage markers of erythroid maturation. 3. Decreases in the cellular content of p35 occurred in both DMSO- and RA-treated FL cells, correlating with the onset of accumulation of cells into G1, and stabilized by 48 hr after initial exposure to either inducer. 4. Down-regulation in the cellular p35 content, thus, appears to be linked to entrance of FL cells into a quiescent substrate and independent of the subsequent capacity for erythroid differentiation.

Colonic epithelial cell proliferation in responders and nonresponders to supplemental dietary calcium

Supplemental dietary calcium decreased and normalized hyperproliferation of colonic epithelial cells in individuals in familial colon cancer kindreds, measured by rates and patterns of [3H]thymidine labeling of epithelial cells in colonic crypts. In whole colonic crypts hyperproliferation was decreased to lower levels in over one-half of the subjects individually studied during the course of the calcium supplementation regimen. The remaining familial colon cancer subjects did not show reductions in cell proliferation measured over the whole crypt. However, when their cell-labeling data were analyzed in regions of the colonic crypt, the size of the proliferative compartment decreased and contracted towards the crypt base after calcium, a pattern typical of individuals at decreased risk for colonic cancer. This contraction of the proliferative region of the crypts occurred through decreased cell labeling in the two crypt compartments closest to the luminal surface and increased cell labeling in the second crypt compartment nearest to the base of the crypt. Following in vitro exposure of colonic epithelial cells to increasing physiological amounts of calcium, cell proliferation in familial colon cancer subjects decreased uniformly and greater heterogeneity in responsiveness was observed in cells from individuals with familial polyposis.

Red cell distribution width, mean corpuscular volume, and transferrin saturation in the diagnosis of iron deficiency

The usefulness of the red cell distribution width, mean corpuscular volume, and the transferrin saturation in diagnosing iron deficiency anemia were evaluated in a retrospective study of 247 anemic hospitalized patients, many of whom had chronic liver disease. A red cell distribution width greater than 15% had a sensitivity of 71% and a specificity of 54% for iron deficiency as diagnosed by a low serum ferritin or bone marrow examination. A mean corpuscular volume less than 80 femtoliters had a sensitivity of 53% and a specificity of 84%. Transferrin saturation less than 16% had a sensitivity of 61% and a specificity of 86%. Because the sensitivities and specificities of these tests are less than reported in studies of healthier populations, they cannot be relied on for screening for iron deficiency in sick hospitalized patients.

The medicalization of normal variants: the case of mitral valve prolapse

Mild mitral valve prolapse, hypoglycemia, irritable colon, and premenstrual syndrome are examples of anatomico-physiologic phenomena that largely overlap with normal. Such "overlap syndromes" become labeled disease entities by the medical community through a process called medicalization. This report uses mitral valve prolapse (MVP) to exemplify the effects of medicalization on patients, physicians, and society. Ascertainment bias and insufficient controlled clinical studies have led to the description of a clinical entity replete with false associations (e.g., mitral valve prolapse syndrome) and overly pessimistic prognostication (e.g., risk of sudden death or endocarditis), leading to clinical overreaction, overtreatment, and unnecessary induction of disability. Though some physical complications may be prevented by recognizing severe MVP, there is substantial risk of iatrogenic harm by attributing complex symptoms and illness behavior to mild MVP, which is probably a normal variant. A three-dimensional analysis of illness experience is presented that may be of use in conceptualizing the clinical approach to overlap syndromes such as mild MVP. Conservative criteria for the diagnosis of significant MVP have been developed at the National Institutes of Health. Treatment of patients with mild MVP must emphasize that it is a normal variant without serious consequences. Because the risks of overmedicalization are so substantial, the impact of diagnostic labels on individual patients and society must be analyzed continually.

Six primary cancers in individuals. Report of four cases

Four patients who had six or more primary cancers are described in this article. Two of the patients had seven cancers each; the most frequent cancer site was the colon. These patients were young at the onset of their first cancer and had a long survival. All the patients had a strong family history of cancer, especially colon cancer. We found that family members of individuals with multiple cancers should be considered to have an increased risk for the development of cancer.

Somatization in primary care: patients with unexplained and vexing medical complaints

Somatizing patients experience or express emotional discomfort and psychosocial distress as physical symptoms. Somatization occurs in a broad spectrum of illnesses, in association with a wide variety of mental disorders, including depression, anxiety, and the somatoform disorders. Primary care providers must detect and treat these patients. Diagnosis is based on positive criteria. Care rests upon conservative medical management and evaluation; a physician-patient relationship based on acceptance, caring, and trust; reinforcement of positive behaviors and elimination of destructive ones; and the gradual use of the relationship to promote healthy relating in the patient.

Proliferation of esophageal epithelial cells among residents of Linxian, People's Republic of China

Histopathologic and tritiated thymidine labeling subjects were carried out on esophageal biopsy specimens of 44 human subjects with cytologic evidence of dysplasia from Linxian, People's Republic of China, a high-risk area for esophageal cancer. With the use of histopathologic criteria, 10 cases showed evidence of dysplasia, 20 hyperplasia, and 14 a near-normal morphology when compared with 21 normal cases studied previously from Jiaoxian, a low-risk area for esophageal cancer in the People's Republic of China. Significantly increased labeling indices were found in the esophageal mucosa of the dysplasia and hyperplasia subjects. There was a gradient of increased expansion in the basal layer of proliferating cells progressing from normal to hyperplasia to dysplasia, with the expansion twice as high in the epithelial cell lining in dysplasia when compared with the findings in the normal and near-normal groups. The correlation of proliferative abnormalities with the severity of precancerous lesions of the esophagus indicates that labeling studies may provide a sensitive adjunct to evaluate risk status and any modifications that might result from nutritional intervention.

Expression of cloned sequences in biopsies of human colonic tissue and in colonic carcinoma cells induced to differentiate in vitro

A computer-based scanning and image-processing system has been developed to quantitate the relative level of expression of each of 4000 cloned complementary DNA sequences in small biopsies routinely removed from the mucosa of normal and neoplastic human large intestine. Individuals have been studied from well-defined population groups in which colonic epithelial cells have progressed to increasingly advanced stages of neoplastic transformation. Comparison of normal colonic mucosa to colonic carcinomas demonstrated alterations in expression of approximately 7% of the cloned sequences; fewer changes were found between benign colonic adenomas and either normal colonic mucosa or carcinomas. A subset of the sequences which change in expression during progression from normal mucosa, to adenoma, to carcinoma showed complementary changes when colon carcinoma cells were induced to differentiate in vitro with sodium butyrate; quantitative correlations between in vivo and in vitro results were highly significant. Comparison of normal colonic mucosa with mucosa from patients with the autosomal dominant disease familial polyposis revealed more extensive alterations in gene expression involving approximately 25% of the clones screened. Flat colonic mucosa in familial polyposis is therefore markedly aberrant and may be highly dedifferentiated, suggesting several possible mechanisms for the very high incidence of cancer that develops in this epithelium.

Tritiated-thymidine labeling of rectal epithelial cells in 'non-prep' biopsies of individuals at increased risk for colonic neoplasia

Recent measurements have shown increased proliferation of colonic epithelial cells in individuals at heightened risk for cancer of the large intestine. This biomarker has facilitated measurements of the effects of nutritional intervention in studies that are attempting to inhibit tumor development in high-risk individuals. In this study, further measurements were made of the proliferation of rectal epithelial cells, when biopsies were removed from mucosa that had not previously been disturbed by any tapwater or other enema preparations. Progressive increases were found in the numbers of [3H]dThd-labeled epithelial cells in rectal crypts, and in labeling index profiles, in patients having previous sporadic adenomas or colon cancer, compared to individuals who had not developed colonic neoplasms. The most quiescent proliferative equilibrium was found in individuals without previous colonic disease. Findings indicated that 'non-prep' rectal biopsies obtained from the most accessible region of the large intestine, show modifications in the biomarker of cell proliferation paralleling colon cancer risk.

Multiple primary malignant tumors

Members of colon cancer-prone nonpolyposis families who had multiple primary malignant tumors were analyzed to determine the frequencies, locations, and stages of their cancers, and the duration of their survival. Colon cancers tended to be more proximal, were in a less advanced stage than in the general population, and in a majority of instances were associated with colonic adenomas. The multiple primary malignant tumors were more common in women, and occurred at a younger age than in the general population. Six or more multiple primary malignant tumors occurred in each of 4 patients. All patients survived for more than 10 yr after the diagnosis of the first cancer. Extracolonic cancers were most frequent in the breast and endometrium.

Evaluation of current criteria used to measure vitamin B12 levels

Because of recent improvements in the serum vitamin B12 assay, literature criteria based on prior assay methods used in measuring B12 levels were evaluated. Of 1,708 B12 levels measured at Bellevue Hospital in a six-month period, 137 in 124 patients were below 200 pg/ml. Contrary to expectations, 81.6 percent of patients with low B12 levels had a mean corpuscular volume (MCV) below 95 fl. Literature-derived criteria missed 30 percent of patients with low B12 levels. Only three of 12 patients with megaloblastic bone marrow or an abnormal Schilling result had B12 levels that were low (below 100 pg/ml), and nine had values in an intermediate range (100 to 200 pg/ml). This suggests that the use of an MCV below 95 fl and a B12 level below 100 pg/ml as abnormal values may not detect clinically important B12 deficiency.

Colonic cell proliferation in familial polyposis

Methods are presented for measuring cell proliferation in inherited gastrointestinal polyposis syndromes and related diseases. Future studies should be aimed at the identification of potentially susceptible individuals and interventions to inhibit tumor development.

Presbycusis and communication

Impaired hearing, so common among older people, often has disastrous consequences. The infirmity, too frequently concealed or unknown by the patient, is invisible to others. Disability and frustration can be lessened considerably by greater awareness on the part of medical and lay people about various helpful measures, which are currently under-utilized. We offer some practical suggestions: Well-trained audiologists can help with both hearing aids and rehabilitation; groups for the hard of hearing can be supportive. The number and varieties of helpful devices increase steadily. Medical personnel, families, and the general public need to learn more about communicating with these people, who need help, often desperately.

Inhibition of human colonic epithelial cell proliferation in vivo and in vitro by calcium

Nine patients at high risk of developing colon cancer were placed on daily p.o. supplementation of 1500 mg of calcium for 4-8 weeks. The colonic epithelial cells in six of these patients showed a statistically significant decrease in their [3H]thymidine labeling indices in tissue culture so that they resembled those of patients at low risk of developing colon cancer. The three nonresponders had similar labeling indices before and after calcium supplementation. Biopsies from each of nine high-risk patients exhibited a decrease in proliferation when they were cultured in vitro with a high level of CaCl2 (2.2 mM compared with the 0.1 mM optimum value for proliferation). Two adenomas and two carcinomas showed a different pattern of response than normal cells, exhibiting no inhibition of growth at 2.2 mM CaCl2. These data indicate that the growth inhibition induced by high levels of extracellular calcium levels is lost at a stage in tumor development before cells become malignant.

Genetic counseling of asymptomatic carriers in a primary care setting. The effectiveness of screening and counseling for beta-thalassemia trait

In a prospective, controlled, stratified, experimental effectiveness study of screening and counseling, 25 000 consecutive adults were screened for thalassemia trait. Eight hundred forty-three adults had a mean corpuscular volume less than 77 fL; 192 (22% of those with microcytosis) had hemoglobin A2 greater than 3.5%, proving beta-thalassemia trait. Video-program, neutral-educational, and patient-centered counseling methods produced equal levels of learning, retention, psychologic impact, and effects on life adjustment immediately and at 2 and 10 months after counseling. Ninety-nine percent of the patients told other persons about the counseling, and 43% had 106 others screened. Factors related to having someone else screened included plans to have children (p less than 0.002), being younger (p less than 0.0025), better education (p less than 0.05), and having high knowledge of thalassemia (p = 0.05). For maximum effectiveness, screening and counseling programs should focus on patients for whom a positive result has high significance.

Expression of murine gamma fetal antigen in adult hematopoietic tissue and during induced differentiation of Friend erythroleukemia cells

Quantitative analysis of extracts of various normal adult CD-1 mouse tissues indicated that the serologically defined murine gamma fetal antigen (gamma-FA) was expressed at high levels in hematopoietic tissue in general and in bone marrow (BM) in particular. Metabolic labeling of isolated BM cells indicated that the BM was a site of gamma-FA synthesis in the adult animal. The size(s) of the antigen immunoprecipitated from labeled BM cells (35 and 27 kilodaltons) with anti-gamma-FA serum correlated well with molecular weight estimates of fibrosarcoma-fetal mouse-associated gamma-FA, as determined by molecular sieve chromatography. For ascertainment of the relationship between hematopoietic cell differentiation and gamma-FA content, a multiparameter flow cytometric approach was used to evaluate gamma-FA levels in Friend erythroleukemia (FL) cells as a function of growth state (blast or dimethyl sulfoxide-differentiated) and cell-cycle compartment. Differentiated G1-arrested FL cells (G1D) possessed significantly lower gamma-FA-associated immunofluorescence as compared to control cells in the G0-G1 substate. Remaining S- and G2 + M-phase cells in differentiated populations demonstrated an even greater reduction in gamma-FA content relative to control cells in the corresponding cell-cycle phases. The available data support the tentative classification of gamma-FA as a murine differentiation antigen.

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.

Proliferative and antigenic modifications in human epithelial cells in chronic atrophic gastritis

For the study of both proliferative and antigenic changes in epithelial cells in a disease predisposing to gastric cancer, endoscopic biopsy specimens were analyzed following removal from individuals with chronic atrophic gastritis (CAG); comparisons were made with specimens from normal gastric mucosa. All subjects were from Nariño, Colombia, the population of which has a high age-adjusted incidence of gastric cancer (150/100,000 population) occurring mainly in gastric antrum. After pulse incubation of biopsy specimens with tritiated thymidine ([3H]dThd), microautoradiographic distributions of [3H]dThd-labeled cells in the epithelial lining of gastric pits were correlated with expression of serologically defined gamma-fetal antigen (FA) as a second marker. Measurements were done both in gastric corpus and in antrum for entire gastric pits and over multiple gastric pit compartments. Total numbers of cells per gastric pit column did not differ between the normal and the CAG specimens either in corpus or in antrum; however, both in corpus and in antrum mean numbers of [3H]dThd-labeled cells per gastric pit column and labeling index were almost twice as large for the CAG population (P less than .006). Labeling index differences also were significant over most gastric pit compartments (P less than .02). In antrum gamma-FA-positive lesions had an expanded proliferative compartment with labeling indices significantly greater than those of antigen-negative lesions (P less than .02). This correlation did not extend to biopsy specimens obtained from corpus of stomach where the frequency of carcinoma is low. Findings indicate a hyperproliferative state in CAG compared to the proliferative state in normal gastric mucosa and, in gastric antrum, a further correlation with expression of gamma-FA in hyperproliferating cells. The two markers can be used to aid definition of the gastric mucosa in a disease associated with the development of gastric cancer and in prophylactic dietary intervention programs.

Hereditary nonpolyposis colorectal cancer (Lynch syndromes I and II). I. Clinical description of resource

Hereditary nonpolyposis colorectal cancer (HNPCC) is comprised of the following: the cancer family syndrome (CFS), or Lynch syndrome II, which shows early-onset proximal colonic cancer predominance and other associated extracolonic adenocarcinomas, particularly endometrial carcinoma; and hereditary site-specific colon cancer (HSSCC), or Lynch syndrome I, which shows all of the same characteristics, except for extracolonic cancer. Nine families with CFS and two with HSSCC provided the resource that was tested for biomarkers (see companion article). All families were meticulously evaluated for genealogy and cancer verification. Biologic specimens were obtained during field visits to areas of closest geographic proximity to the families. Cancer education and recommendations for surveillance/management were provided to patients and their physicians. Additionally, 40 families (about 3000 individuals) with either CFS or HSSCC have been ascertained. Syndrome cancers were restricted to direct-line relatives as opposed to nonbloodline relatives, arguing against involvement of environmental factors. One documented clinical feature was a predilection for proximal versus distal colonic cancer in both CFS and HSSCC kindreds. This has important clinical significance in that it clarifies the need for instituting effective surveillance earlier to detect the predominantly proximal colonic cancers.

Proliferative abnormalities of the oesophageal epithelium of Chinese populations at high and low risk for oesophageal cancer

Studies on the pattern of proliferation of epithelial cells from the oesophagus of 33 individuals from Linxian, a high-risk area for oesophageal cancer in China, and of 22 subjects from Jiaoxian, a low-risk area for the same cancer in China, were performed using thymidine labelling. Oesophageal biopsies were obtained during endoscopic surveys carried out in these 2 populations. A clear difference was observed between the 2 groups; the high-risk group showed cell proliferation in the upper layers of the epithelium more often than the low-risk group. No difference was found in the cell proliferation patterns of subjects with oesophagitis and those without oesophagitis in the high-risk area. This finding could suggest that the tritiated thymidine assay may be a more sensitive method to characterize the precancerous lesions of the oesophagus in high- and low-risk populations than simple histological evaluation.

Altered actin cytoskeletal patterns in two premalignant stages in human colon carcinoma development

Primary culture of human colonic biopsies converts the single cell thick epithelial layer from a highly indented sheet in vivo into a flat patch on the surface of a Petri dish. Migration of cells from biopsies in a continuous sheet to form the patch cultures allows the cultured cells in large part to retain the junctional complexes and membrane interdigitations which connect adjacent cells in vivo and therefore to maintain their spatial relationships to neighboring cells. Migration of the cells onto a flat surface also allows visualization of their actin cables (E. Friedman, M. Verderame, S. Winawer, and R. Pollack, Cancer Res., 44: 3040-3050, 1984). Actin organization patterns have been studied in primary patch cultures of colonic epithelial cells from four stages in the development of colon cancer: normal tissue, normal-appearing but preneoplastic cells characteristic of familial polyposis patients, benign tumors or adenomas from familial polyposis patients, and benign and malignant tumors from patients in the general population. Carcinomas exhibited the least number of actin cables, while adenomas contained the greatest concentration. Similar actin patterns were seen in both familial polyposis and nonpolyposis adenomas. The preneoplastic prebenign tumor stage characteristic of familial polyposis patients had less actin cables than either normal cells or benign tumor cells. Thus actin organization loss characterized the transition from the normal colonic epithelial cell to the preneoplastic nontumor cell. The ability to form actin cables was then regained with the transition from the preneoplastic pretumor cell to the benign tumor cell and lost again with the benign tumor to malignant tumor transition. The complexity of these changes in actin organization during the step-wise transformation of colonic epithelial cells was not predicted from the simple model of actin cable loss accompanying fibroblast transformation.

Seventh-Day Adventist vegetarians have a quiescent proliferative activity in colonic mucosa

The proliferation of epithelial cells in colonic mucosa was studied in humans at varying degrees of risk for colon cancer. Seventh-Day Adventist vegetarians, known to have significantly lower mortality from colon cancer than the general U.S. population, had the most quiescent proliferative activity of mucosal epithelial cells. Increased replication and expansion of the proliferative compartment accompanied increased colon cancer risk. The analytical methods of this study may be useful in assessing the influence of dietary components involved in the initiation, promotion or inhibition of colon cancer, and in developing strategies for nutritional intervention.

Proliferative and antigenic properties of rectal cells in patients with chronic ulcerative colitis

Two markers related to preneoplasia were studied simultaneously in ulcerative colitis (UC). The renewal of the rectal epithelial cells together with expression of second-trimester fetal antigen (STFA) were evaluated in nine patients with UC and four healthy subjects. Endoscopic biopsies were incubated with tritiated thymidine. Cell renewal was studied with microautoradiography, and the antigenic properties of the cells were evaluated by indirect immunofluorescence. At the time of the study, all the UC patients were in a mildly active or in a quiescent stage of the disease; their biopsies did not show dysplastic or neoplastic changes in epithelial cells. STFA was expressed in five UC patients. The analysis of cell renewal in this group revealed a shift of the proliferative compartment towards the luminal surface of the colonic crypts. By contrast, the patient group with STFA-negative reactions showed a pattern of cell proliferation similar to that observed in the controls. These results suggest that the expression of STFA in colonic mucosa is associated with an expansion of the epithelial stem cell population or with arrested cell differentiation, and it may represent a phenotypic marker of proneness of the mucosa toward neoplastic development.