Multitarget Stool DNA Test Performance in an Average-Risk Colorectal Cancer Screening Population.

INTRODUCTION: We set out to evaluate the performance of a multitarget stool DNA (MT-sDNA) in an average-risk colonoscopy-controlled colorectal cancer (CRC) screening population. MT-sDNA stool test results were evaluated against fecal immunochemical test (FIT) results for the detection of different lesions, including molecularly defined high-risk adenomas and several other tumor characteristics. METHODS: Whole stool samples (n = 1,047) were prospectively collected and subjected to an MT-sDNA test, which tests for KRAS mutations, NDRG4 and BMP3 promoter methylation, and hemoglobin. Results for detecting CRC (n = 7), advanced precancerous lesions (advanced adenoma [AA] and advanced serrated polyps; n = 119), and non-AAs (n = 191) were compared with those of FIT alone (thresholds of 50, 75, and 100 hemoglobin/mL). AAs with high risk of progression were defined by the presence of specific DNA copy number events as measured by low-pass whole genome sequencing. RESULTS: The MT-sDNA test was more sensitive than FIT alone in detecting advanced precancerous lesions (46% (55/119) vs 27% (32/119), respectively, P < 0.001). Specificities among individuals with nonadvanced or negative findings (controls) were 89% (791/888) and 93% (828/888) for MT-sDNA and FIT testing, respectively. A positive MT-sDNA test was associated with multiple lesions (P = 0.005), larger lesions (P = 0.03), and lesions with tubulovillous architecture (P = 0.04). The sensitivity of the MT-sDNA test or FIT in detecting individuals with high-risk AAs (n = 19) from individuals with low-risk AAs (n = 52) was not significantly different. DISCUSSION: In an average-risk screening population, the MT-sDNA test has an increased sensitivity for detecting advanced precancerous lesions compared with FIT alone. AAs with a high risk of progression were not detected with significantly higher sensitivity by MT-sDNA or FIT.

Detection of nuclear matrix proteins in serum from cancer patients.

Morphological characteristics of the cell nucleus have long been used by pathologists in the clinical diagnosis of cancer. The nuclear matrix of the cell, the structure that serves to organize the chromatin within the nucleus, is known to reflect these morphological characteristics with regard to cell and cancer type. Monoclonal antibodies were developed to extracted nuclear matrix proteins. These antibodies were used in two-site immunometric assays to detect soluble nuclear matrix proteins in the supernatants of two dying cell lines and 15 tumor tissues. Furthermore, nuclear matrix proteins were detected at elevated levels in the sera of cancer patients compared with normal patient sera. In one assay, 63.2% of cancer sera read above 95% of normal sera, and in another assay, 73.7% of cancer sera read above 95% of the normal sera. With the development of monoclonal antibodies with greater cancer specificity, the detection of circulating nuclear matrix proteins may become an important clinical tool in the diagnosis and monitoring of cancer.

Propranolol in the treatment of thyrotoxicosis by subtotal thyroidectomy.

Subtotal thyroidectomy was performed in 40 patients with thyrotoxicosis in whom propranolol alone was used as preparation for surgery. Propranolol was given orally in a dose of 40 mg every 6 h for a mean preoperative period of 17 days (range 4-60 days) and continued for seven days after operation. The mean +/- SE blood loss at operation was only 160 +/- 20 ml. The period of follow-up was from three to nine months. Recurrent thyrotoxicosis has not occurred in any patient. Low levels of total serum triiodothyronine (T3) and total serum thyroxine (T4) were observed in the early postoperative weeks in some patients and were associated with symptoms of mild hypothyroidism, but by six months in the presence of a raised serum thyrotropin (TSH) the thyroid hormone levels returned to normal. Permanent hypothyroidism developed in only two patients. Despite normal or low total serum T3 and T4 levels, the TSH response to thyrotropin-releasing hormone (TRH) was absent in all patients one week after operation. At four weeks and at eight weeks, the response was absent or sub-normal in 70% and 20% of the patients respectively, indicating a delay in the recovery of the hypothalamo-pituitary axis previously exposed to high levels of T3 and T4. It is considered that subtotal thyroidectomy for thyrotoxicosis in patients prepared with propranolol is an acceptable procedure which has some advantages over the conventional preparation with carbimazole and potassium iodide, not the least of which are the potential reduction in preparation time, the more flexible timing of operation, and the reduced operative blood loss.

D-glucose permeability of black lipid membranes modified by human erythrocyte membrane fractions.

The D-glucose permeabilities of bimolecular lipid membranes formed from egg lecithin, cholesterol and human erythrocyte membrane fractions obtained using several fractionation procedures have been measured in order to assess their monosaccharide transport activity. The electrical properties of the bilayers containing the membrane fractions have also been measured and the bilayer thicknesses calculated. The observed D-glucose permeability coefficients are several orders of magnitude lower than that of the human erythrocyte membrane, indicating that none of the membrane fractions possessed significant glucose carrier activity. It is concluded that more refined techniques for incorporating membrane fractions into BLMs will be necessary before the monosaccharide transport system can be simulated in vitro.

A high resolution two-dimensional gel electrophoresis and silver staining protocol demonstrated with nuclear matrix proteins.

An improved two-dimensional gel electrophoresis procedure has been developed utilizing isolated nuclear matrix proteins. The proteins of the cellular nuclear matrix are tissue specific. They are an example of a protein set whose two-dimensional electrophoretic patterns afford much information of clinical significance. However, current two-dimensional gel techniques were not completely satisfactory for the small amounts of protein present in tissue samples. There was a need for a two-dimensional gel procedure which was capable of increased sensitivity and resolution and at the same time was reliable and reproducible. This has been accomplished by implementing several modifications to the current two-dimensional gel procedures. In addition, changes were introduced in the silver staining process of the gels to increase the signal to background ratio. The overall procedure affects a dramatic increase in the resolution and clarity of the proteins visualized on two-dimensional gels and is no more laborious than current techniques.

Bromocriptine suppression of the thyrotrophin response to thyrotrophin releasing hormone.

A single oral dose of 5 mg of bromocriptine significantly lowered the TSH response to 200 microgram TRH intravenously in eight healthy men compared with control experiments in the same subjects. This finding may be relevant in chronic bromocriptine therapy.

Localization of nuclear matrix proteins (NMPs) in multiple tissue types with NM-200.4 (an antibody strongly reactive with NMPs found in breast carcinoma).

Nuclear matrix proteins (NMP) are nonhistone proteins found in the nucleus of many eukaryotic cells. Furthermore certain NMPs are reported to be cell-type specific and expressed differentially by malignant cells. To study the specificity of NM-200.4 (an antibody reactive to NMPs extracted from cultured breast carcinoma cells of the T-47D line), cancers and benign tissues from multiple body sites were surveyed. All 17 breast carcinomas showed strong reactivity to tumor cell nuclei. Also nuclei from one of two lung carcinomas, a papillary thyroid carcinoma, an ovarian fibroma, and a lymphoma were strongly reactive. One leiomyosarcoma and a dermoid cyst were negative. Although 1 benign breast with duct hyperplasia showed moderate reactivity, only 1 of 10 benign breast biopsies without hyperplasia showed reactivity. Three of 4 skin biopsies, 2 liver biopsies, 6 of 9 kidney biopsies, and 5 of 10 gastrointestinal mucosal biopsies showed reactivity in benign nuclei. It is concluded that, although breast carcinoma nuclei showed the most consistent reactivity for NM-200.4, both benign and malignant nuclei from other body sites also show reactivity.

Failure of luteinizing hormone-releasing hormone and insulin to further augment thyrotrophin release in primary hypothyroidism.

The effect of luteinizing hormone-releasing hormone (LH-RH) and insulin-induced hypoglycaemia on the release of thyrotrophin (TSH) was studied in five patients with primary hypothyroidism. All five patients had elevated TSH levels with an exaggerated rise in response to thyrotrophin-releasing hormone (TRH). No rise over control values was found after LH-RH or insulin indicating that despite the augmentation of TSH release in primary hypothyroidism there is no alteration of the specificity of the thyrotroph response.

Recovery of hypothalamic-pituitary-adrenal function after intermittent high-dose prednisolone and cytotoxic chemotherapy.

Hypothalamic/pituitary and adrenal (HPA) function was assessed in ten patients who received intermittent high-dose prednisolone and cytotoxic chemotherapy for 5-40 months. Standard insulin hypoglycaemia (IHT), thyrotrophin-releasing hormone and tetracosactrin tests were performed 36 hr after the last dose of prednisolone and subsequently 10 days--52 weeks after completion of all chemotherapy. In the first tests there was evidence of impaired hypothalamic-pituitary function judged by peak adrenocorticotrophic hormone (ACTH), growth hormone (GH) and thyrotrophin (TSH) responses, and corresponding plasma corticosteroid responses were sub-normal in five patients. In the final IHTs, seven patients had persistently subnormal ACTH responses but all the corresponding plasma corticosteroid responses returned to normal. Mean peak corticosteroid responses to insulin and tetracosactrin and peak GH responses were significantly greater than in the first tests. Such chemotherapy regimens may have prolonged effects on hypothalamic/pituitary function but the demonstration of normal corticosteroid responses to hypoglycaemia and tetracosactrin indicates that these patients' stress responses will be normal as early as 10 days after treatment is stopped.

Prevalence of severe growth hormone deficiency.

Four hundred and forty-nine short children, who were all over 2-5 standard deviations below the mean height for age, were identified by screening the heights of 48 221 6- to 9-year-old children in three Scottish cities. Most were screened for growth hormone deficiency (GHD). The prevalence of severe GHD in this sample may have been as high as 1 in 4018, much higher than reported. The findings suggest that present referral patterns may account for the delayed or missed diagnosis of the condition in girls or children with less severe short stature.

Response to thyrotrophin releasing hormone in Klinefelter's syndrome.

In eleven patients with Klinefelter's Syndrome TSH, T4 and T3 levels have been measured after stimulation with TRH. The eleven patients included three who had been noted to have a low radioactive iodine uptake and two of these also had abnormally low T4 levels. Three of the patients were receiving androgen replacement therapy. A normal response to TRH was observed in all cases.

Temporary hypothyroidism after surgical treatment of thyrotoxicosis.

Mild clinical hypothyroidism associated with low levels of serum total thyroxine (T4) and tri-iodothyronine (T3) and raised levels of serum thyroid-stimulating hormone (T.S.H.) has been observed in 14 of 40 patients (35%) in the early months after a subtotal thyroidectomy for thyrotoxicosis under cover of propranolol. In 10 of the patients, however, the hypothyroidism was temporary and at 6 months after operation the thyroid hormone levels were normal and the serum T.S.H. levels had fallen. In 4 of the patients in whom clinical and biochemical evidence of hypothyroidism persisted 6 months postoperatively, long-term T4 replacement therapy was instituted. It is concluded that the diagnosis of permanent hypothyroidism should not be made with confidence before 6 months have elapsed after operation and that the incidence of hypothyroidism following the surgical treatment of thyrotoxicosis may have been overestimated in the past.

Spectrum of thyroid function in patient's remaining in remission after antithyroid drug therapy for thyrotoxicosis.

Thyroid function was assessed in 110 patients who were in remission for a period of 7-6 +/- 0-6 years (mean +/- S.E.) (range 0-25--25 years) after the withdrawal of antithyroid drug therapy for thyrotoxicosis. On the basis of clinical examination and on the results of thyroid-function tests, the following group of patients were identified: (I) euthyroid with normal plasma-total thyroxine (T4) and triiodothyronine (T3) concentrations, but an absent or subnormal response of plasma-thyrotrophin (T.S.H.) to thyrotrophin-releasing hormone (T.R.H.) (16%); (II) euthyroid with normal concentrations of plasma total T4 and T3 and a normal plasma-T.S.H. response to T.R.H. (59%); (III) euthyroid with normal concentrations of circulating thyroid hormones and a normal basal plasma-T.S.H., but an exaggerated plasma-T.S.H. response to T.R.H. (13%); (IV) euthyroid with normal plasma total T4 and T3 concentrations, but a raised basal plasma-T.S.H. concentration and an exaggerated plasma-T.S.H. response to T.R.H. (6%); (V) hypothyroid (6%). Although the need for short-term follow-up to identify those patients treated with antithyroid drugs who will relapse is well recognised, 16% of all patients in remission for longer than 4 years (10-8 +/- 0-7 years) in the present study showed some degree of thyroid failure. Evidence of hypothyroidism was associated with an increased frequency of thyroid microsomal antibodies. If the morbidity of the late development of hypothyroidism is to be avoided, patients who have been treated with antithyroid drugs should have long-term follow-up, as do patients treated surgically or with radioiodine.

The effect of dialysate calcium concentration on 1alpha-hydroxyvitamin D3 on skeletal calcium loss and hyperparathyroidism in haemodialysis patients.

The response of hyperparathyroidism and skeletal calcium loss in haemodialysis patients to treatment with 1alpha-hydroxyvitamin D3 and a dialysate calcium concentration of 1.375 mmol/l was compared with the response to treatment with a dialysate calcium concentration of 1.375 or 1.75 mmol/l alone over a 6 month period. In patients treated with 1alpha-hydroxyvitamin D3 there was a significant rise in plasma calcium associated with a significant fall in plasma alkaline phosphatase and plasma parathyroid hormone as well as resolution of sub-periosteal erosions. In these patients there was a significant rise in the calcium content of the forearm assessed by neutron activation analysis in comparison to patients treated with a dialysate calcium concentration of 1.75 or 1.375 mmol/l alone. In patients treated with a dialysate calcium concentration of 1.375 or 1.75 mmol/l alone there was no significant change in the plasma calcium, alkaline phosphatase or parathyroid hormone after 6 months and in these patients subperiosteal erosions either did not change or became worse. No significant difference in the response in these two groups was observed. This study indicates that treatment of haemodialysis patients with 1alpha-hydroxyvitamin D3 is significantly more effective than treatment with a dialysate calcium concentration of 1.375 or 1.75 mmol/l alone in preventing progression of hyperparathyroidism and skeletal calcium loss.