Biomedical subjects

J F Moley

Publications and source records attributed to J F Moley.

54 records · Page 3Linked to original sources

PubMed1995

Laparoscopic detection of hepatic metastases in patients with residual or recurrent medullary thyroid cancer.

BACKGROUND: After initial operations for medullary thyroid cancer (MTC), reoperation with removal of metastatic disease confined to the neck may benefit some patients. The identification of distant metastases precludes the possibility of curative reoperation. METHODS: Forty-one patients with hypercalcitoninemia after initial surgical treatment for MTC underwent laparoscopic (n = 36) or open (n = 5) examination and biopsy of the liver. Thirty-seven of these patients underwent imaging by computed tomography (CT), magnetic resonance imaging (MRI) of the liver, or both, and 17 underwent selective venous catheterization (SVC) with measurement of hepatic and peripheral vein stimulated calcitonin levels. RESULTS: Liver metastases were found in eight patients, seven by laparoscopy and one by open examination. Seven of these patients had normal CT or MRI scans of the liver. Laparoscopy or open liver examination revealed metastases in 2 of 11 patients with elevated hepatic vein-peripheral vein stimulated calcitonin ratios (greater than 1.3). Metastases appeared as small (less than 5 mm), bright white nodules on the surface of the liver. CONCLUSIONS: Direct examination and biopsy of the liver by laparoscopy may show small deposits of metastatic MTC in patients with normal CT and MRI scanning.

Adolescent↗

PubMed1995

Medullary thyroid cancer.

Medullary thyroid cancer is a tumor of the thyroid C cells that occurs in sporadic and hereditary clinical settings. Genetic testing of at-risk individuals is available and has been applied to patient management. Plasma calcitonin levels are a very sensitive marker for the presence of disease. Surgery offers the best hope for cure and also is an effective modality for managing metastatic and recurrent disease.

Biomarkers, Tumor↗

PubMed1994

Predictive DNA testing and prophylactic thyroidectomy in patients at risk for multiple endocrine neoplasia type 2A.

BACKGROUND: Missense germ-line mutations in the RET protooncogene are associated with multiple endocrine neoplasia type 2A (MEN 2A). Detection of these mutant alleles in kindred members predicts disease inheritance and provides the basis for preventative thyroidectomy. METHODS: A polymerase chain reaction (PCR)-based genetic test for the 19 known RET mutations was designed to study 132 members of 7 kindreds with MEN 2A. Haplotypes also were constructed using genetic markers flanking the MEN 2A locus. Plasma calcitonin (CT) concentrations were determined before and after provocative testing. RESULTS: Direct DNA testing and haplotype analysis showed that 21 of 58 kindred members at risk for disease had inherited a mutation in the RET protooncogene associated with MEN 2A. Plasma CT concentrations were elevated in 9 of the 21 family members, but were normal in 12. After genetic counseling, 13 of the 21 kindred members (6 with normal and seven with elevated plasma CT levels), consented to immediate thyroidectomy. In each patient, the resected thyroid gland showed C-cell hyperplasia with or without medullary thyroid carcinoma. There were no metastases to regional lymph nodes, and postoperative stimulated plasma CT levels were normal. CONCLUSION: The PCR-based direct DNA test for RET mutations is accurate, rapid, and reproducible. For all 132 individuals evaluated, the results of direct DNA analysis were consistent with haplotype studies. The direct test for mutations in the RET protooncogene is the preferred method for screening MEN 2A kindreds. In family members who have inherited a RET mutation, total thyroidectomy is indicated, regardless of the plasma CT values.

Adolescent↗

PubMed1993

Mutations in the RET proto-oncogene are associated with MEN 2A and FMTC.

Multiple endocrine neoplasia type 2A (MEN 2A) and familial medullary thyroid carcinoma (FMTC) are dominantly inherited conditions which predispose to the development of endocrine neoplasia. Evidence is presented that sequence changes within the coding region of the RET proto-oncogene, a putative transmembrane tyrosine kinase, may be responsible for the development of neoplasia in these inherited disorders. Single strand conformational variants (SSCVs) in exons 7 and 8 of the RET proto-oncogene were identified in eight MEN 2A and four FMTC families. The variants were observed only in the DNA of individuals who were either affected or who had inherited the MEN2A or FMTC allele as determined by haplotyping experiments. The seven variants identified were sequenced directly. All involved point mutations within codons specifying cysteine residues, resulting in nonconservative amino acid changes. Six of the seven mutations are located in exon 7. A single mutation was found in exon 8. Variants were not detected in four MEN 2B families studied for all exon assays available, nor were they detectable in 16 cases of well documented sporadic medullary thyroid carcinoma or pheochromocytoma that were tested for exon 7 variants. Coinheritance of the mutations with disease and the physical and genetic proximity of the RET proto-oncogene provide evidence that RET is responsible for at least two of the three inherited forms of MEN 2. Neither the normal function, nor the ligand of RET are yet known. However, its apparent involvement in the development of these inherited forms of neoplasia as well as in papillary thyroid carcinoma suggest an important developmental or cell regulatory role for the protein.

Amino Acid Sequence↗

PubMed1993

Reoperation for recurrent or persistent medullary thyroid cancer.

BACKGROUND: Initial operations for medullary thyroid cancer (MTC) frequently do not eradicate all disease, as evidenced by persistently elevated levels of stimulated plasma calcitonin. METHODS: Thirty-two patients with MTC and elevated stimulated plasma calcitonin levels after thyroidectomy were studied between 1990 and 1993. Thirty-five repeat neck explorations and microdissections were performed. Four patients also underwent a median sternotomy and mediastinal dissection. RESULTS: In nine patients (group 1), stimulated plasma calcitonin levels were undetectable after reoperation, whereas in 13 cases (group 2) the calcitonin levels decreased by 40% or more. In 10 cases (group 3) the CT levels did not decrease. Primary tumors that exhibited invasive features (invasion of adjacent structures or extranodal or extracapsular spread) were found more often in patients from group 3 than in patients from groups 1 or 2 (p < 0.05, Fisher's exact test). CONCLUSIONS: Reoperation resulted in normalization of calcitonin levels in 28% of patients and a decrease in calcitonin levels by 40% or more in another 42% of patients. The data also suggest that patients whose primary MTC has invaded tissues beyond the thyroid gland or a lymph node capsule are less likely to benefit from repeat operation.

Adolescent↗

PubMed1992

Consistent association of 1p loss of heterozygosity with pheochromocytomas from patients with multiple endocrine neoplasia type 2 syndromes.

Pheochromocytomas and medullary thyroid cancers (MTCs) are neuroendocrine tumors which arise sporadically or as part of the multiple endocrine neoplasia type 2 (MEN-2) hereditary syndromes. The most consistent molecular genetic abnormality which has been described in these tumors is loss of heterozygosity (LOH) of the short arm of chromosome 1 (1p). This finding is particularly interesting because the predisposition gene for the hereditary form of these tumors has been mapped to chromosome 10, but LOH on chromosome 10 in MEN-2 tumors is found rarely. We have used a battery of 1p DNA probes to elucidate the region of loss of 1p in 18 pheochromocytomas and 27 MTCs. Using restriction fragment length polymorphism analysis, we identified loss of all or a portion of 1p in 12 of 18 pheochromocytomas. 1p LOH was identified in nine of nine pheochromocytomas in MEN-2A and -2B patients, compared with only two of seven sporadic pheochromocytomas. We also found 1p LOH in one of two von Hippel-Lindau patients. LOH on 1p was noted in only three of 24 informative MTCs, and these were from patients with MEN-2A. In most of the pheochromocytomas, the entire short arm of chromosome 1p appears to have been lost; however, in three of the non-MEN pheochromocytomas and in three MEN-2A MTCs, the region of loss is smaller, allowing estimation of the smallest region of overlap. The combined data for MTCs and pheochromocytomas suggest that the smallest region of overlap of LOH is bounded by D1S15 (1pter-p22) and D1Z2 (1P36.3), excluding a region around MYCL (1p32). Although other regions of 1p should not be completely ruled out, the data suggest that this region may harbor a tumor suppressor gene or genes whose inactivation is important in the development of these tumors. Furthermore, the strong association between 1p LOH and the MEN-2 syndromes, especially in pheochromocytomas, suggests a relationship between the predisposition gene on chromosome 10 and the loss of the suppressor gene on 1p. Alternatively, other loci may be more important in sporadic disease.

Adrenal Gland Neoplasms↗

PubMed1992

Oncogene and growth factor expression in MEN 2 and related tumors.

Pheochromocytomas occur sporadically or in individuals affected by inherited syndromes including multiple endocrine neoplasia (MEN) type 2A and 2B, neurofibromatosis, and the von Hippel-Lindau syndrome (vHL). Medullary thyroid carcinomas (MTCs) also occur sporadically or as part of MEN 2A, MEN 2B, and familial MTC. Little is known of the molecular genetic background of these tumors. We have shown previously that activation of the N-ras, H-ras, and K-ras oncogenes does not occur in these tumors, but that deletions of the short arm of chromosome 1 are extremely common (> 60%) and may indicate loss of a suppressor gene in the chromosomal region 1p31-36. We have examined the structure and expression of N-myc, c-myc, L-myc, c-mos, nerve growth factor (beta-NGF), and the low affinity nerve growth factor receptor (LNGFR) in a series of pheochromocytomas and MTCs from patients with hereditary and sporadic diseases. Southern analysis, using radiolabeled DNA probes, revealed no evidence of amplification or rearrangement of these genes in any normal or tumor tissues except for loss of heterozygosity at the L-myc locus (1p32) in 9 pheochromocytomas from patients with MEN 2A or MEN 2B, in 5 of 11 non-MEN pheochromocytomas, and in 3 of 24 non-MEN MTCs. Gene expression at the RNA level was examined by Northern analysis or ribonuclease protection assay (RPA) using radiolabeled DNA or cRNA probes. C-myc transcripts were detectable at low levels in all tumors tested.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Gland Neoplasms↗

PubMed1991

Low frequency of ras gene mutations in neuroblastomas, pheochromocytomas, and medullary thyroid cancers.

Little is known about the prevalence and significance of ras gene activation in neural crest tumors such as neuroblastomas, pheochromocytomas, and medullary thyroid cancers (MTCs). Therefore, we analyzed DNA from 10 human neuroblastoma cell lines and 10 primary human pheochromocytomas for activating mutations in N-ras, H-ras, and K-ras. We also studied DNA from 24 primary neuroblastomas and 10 MTCs for N-ras mutations. ras genes were analyzed by direct sequencing of specific DNA fragments amplified by the polymerase chain reaction. With the exception of the SK-N-SH cell line, the examined ras gene sequences were normal in all the neuroblastomas, pheochromocytomas, and MTCs tested. A single point mutation was identified at codon 59 (GCT(ala)----ACT(thr)) in one N-ras allele in an SK-N-SH subline. Interestingly, this mutation is different from the activating codon 61 mutation which resulted in the initial identification of N-ras from SK-N-SH DNA. Therefore, we analyzed the sequences of earlier passages and sublines of the SK-N-SH cell line, but mutations at codon 59 or 61 were not detected, suggesting that neither mutation was present in the primary tumor. Our results indicate that N-ras mutations may occur spontaneously during in vitro passage of cell lines but rarely, if ever, occur in primary neuroblastomas, pheochromocytomas, and MTCs. In addition, we have not found H-ras or K-ras mutations in any neuroblastoma cell line or primary pheochromocytoma.

Adrenal Gland Neoplasms↗

PubMed1991

Biology of tumors of the peripheral nervous system.

Tumors of the peripheral nervous system include neuroblastomas, pheochromocytomas, and neuroepitheliomas. Neuroblastomas and pheochromocytomas are adrenergic in origin and share certain genetic features, whereas neuroepitheliomas are thought to be cholinergic and are characterized by distinct genetic features. Neuroblastomas are characterized by deletion of the short arm of chromosome 1 (1p), amplification of the MYCN proto-oncogene, and hyperdiploidy in subsets of tumors. All three of these genetic features have prognostic value in subsets of patients. Allelic loss of 14q also occurs with increased frequency, but the prognostic importance of this abnormality is not known yet. Pheochromocytomas have not been studied as extensively, but allelic loss for 1p appears to be a frequent change, and no clear examples of oncogene activation have been identified to date. Neuroepitheliomas are characterized by translocation between chromosomes 11 and 22. Although they have a characteristic pattern of proto-oncogene expression, it is not clear that any of these oncogenes are activated specifically, and no sites of allelic loss have been identified to date. Thus, cytogenetic and molecular analysis of neuroblastomas, pheochromocytomas, and neuroepitheliomas are useful in distinguishing them from each other and from other tumors in selected cases. Furthermore, certain genetic markers are useful in predicting clinical behavior, especially for neuroblastoma.

Adrenal Gland Neoplasms↗

PubMed1988

Body composition changes in rats with experimental cancer cachexia: improvement with exogenous insulin.

Exogenous insulin treatment has been shown to improve food intake and host weight of cachectic tumor-bearing (TB) rats, but the composition of the host weight gain has not been quantitated. Sixty-six Fischer 344 rats were randomized to seven groups: early nontumor-bearing (NTB) (n = 10) who underwent compositional analysis (CA) on the day the methylcholanthrene sarcoma was implanted in TB rats; pretreatment-NTB (n = 10) and pretreatment-TB (n = 10) who underwent CA 25 days later when rats began treatment with saline or insulin; and finally saline-treated NTB (n = 9), saline-treated TB (n = 9), insulin-treated NTB (n = 9), and insulin-treated TB (n = 9), who underwent CA following 5 days of treatment with daily saline or neutral protamine hagedorn insulin 2 units/100 g. Body weight and food intake were measured daily. For compositional analysis, the tumor was separated from the host in TB rats and the entire rat in NTB animals was homogenized, lyophilized and analyzed for fat, water, protein, potassium, chloride, and sodium. The tumor was processed in a similar fashion. In response to insulin, NTB rats ate significantly more food, and had an increase in body weight gain. Compositional analysis of insulin-treated NTB rats indicated a slight, but insignificant, increase in body fat and a similar insignificant decrease in body protein. TB rats ate significantly less than NTB rats during the 5-day experimental period, and insulin treatment significantly increased food intake to levels similar to NTB animals. Compositional analysis indicated that the tumor-bearing state resulted in a significant decrease in total host water, protein, fat, potassium, sodium, and chloride. Insulin administration resulted in preservation of host nitrogen, fat, potassium, sodium, and chloride in cachectic tumor-bearing rats. Insulin treatment did not affect tumor dry weight or composition. The results suggest that exogenous insulin, can preserve normal host composition of TB rats during cachectic decline.

Animals↗

PubMed1987

Preoperative insulin reverses cachexia and decreases mortality in tumor-bearing rats.

As a model of surgical stress in the cancer-bearing animal, we resected large flank sarcomas from cachectic rats under ether anesthesia and closed wounds primarily. The metabolic cost of tumor resection was measured using a long-term continuous indirect calorimeter. In the immediate postresection period energy balance decreased and host energy expenditure increased significantly (P less than 0.005). In animals with similar tumor weights, mortality following resection was determined by the degree of cachectic depletion. We then considered whether improvement of preoperative host nutritional status with insulin treatment might improve a subsequent surgical outcome. Insulin, when administered exogenously to cachectic tumor-bearing rats, has been shown to stimulate food intake and preserve host weight and does not stimulate tumor growth. When individual rats bearing a cachexia-producing flank sarcoma demonstrated a decline in food intake to less than 75% of predicted (approximately 25 days after tumor implantation), they were randomized to receive either daily injections of NPH insulin (2 units/100 g/day) for 5 days or no treatment for 5 days. Animals then underwent tumor resection and 14-day survival was measured. All resections were performed in an unbiased manner without the surgeon's knowledge of each rat's treatment status. In an experiment using 59 rats, insulin-treated rats had a threefold higher 5-day preoperative food intake and did not lose weight in the preoperative period, while untreated rats lost 17 g (P less than 0.001). Mortality in the insulin-treated group was 10% versus 28% in the untreated group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1986

Home parenteral nutrition for patients with advanced intraperitoneal cancers and gastrointestinal dysfunction.

The use of total parenteral nutrition (TPN) in patients with advanced, untreatable cancer is controversial. Occasionally, however, damage to bowel by tumor, radiation, or surgery renders these patients unable to eat and TPN may be indicated to prevent premature death from starvation. We have used Home Parenteral Nutrition (HPN) to support three patients with advanced, untreatable abdominal cancer and inability to eat. Morbidity was minimal and survival times were 24, 6 and 1.5 months. Payment was covered by third party agencies. All patients and their families were gratified by the ability to return home with nutritional support. HPN can be used to support terminal cancer patients with bowel obstruction and may afford them longer survival. Ideally, patients considered for this should be well motivated, with good support systems, and with survival estimated to be at least months.

Abdominal Neoplasms↗

PubMed1985

Parabiotic transfer of cancer anorexia/cachexia in male rats.

To demonstrate that the anorexia and depletion of cachexia reverses on tumor removal, F344 rats underwent sarcoma resection when their food intake fell to 0 g/day. In survivors of surgery, reversal in food intake was apparent within 3 days postoperatively, followed after 2 days by gain in host weight. To detect whether the transmission of anorexia/cachexia in these tumor-bearing (TB) rats was via the circulation, four groups were studied: single non-tumor bearing (NTB); single TB; parabiotic NTB; and parabiotic TB. The measured blood exchange rate between parabiotic halves was 1.2-1.5%/min. No cachectic effect was detected in either half of the NTB parabionts. There was no evidence of sarcoma metastases in the tumor-free half of the parabiotic TB pair. All the rats associated with the presence of tumor showed cachectic effects but the degree and timing of effect varied among the three conditions, single TB, parabiotic TB half, and parabiotic tumor-free half. In all variables examined (fall in food intake, time of first fall in food intake, host weight loss, elevation of blood urea nitrogen) the severities were always in the same sequence: single TB greater than parabiotic TB half greater than parabiotic tumor-free half greater than NTB. In addition, the TB parabiotic pair had a significantly longer survival time and grew a significantly larger tumor than did the single TB animal. The parabiotic tumor had a slower initial growth rate and a slower deceleration rate than the singlet tumor. These results provide evidence for the humoral mediation of cancer-associated cachexia.

Animals↗

PubMed1985

Insulin reversal of cancer cachexia in rats.

The anabolic effects of exogenous neutral protamine hagedorn insulin on tumor-bearing (TB) and non-tumor-bearing (NTB) rats were examined. Exogenous insulin (2 units/100 g/day) produced similar hypoglycemia in TB and NTB rats. Food intake and body weight gain were significantly increased by insulin in NTB rats. In TB rats in an early stage of cachexia, insulin increased food intake and host weight (total body weight minus tumor weight). In TB rats with severe cachexia, insulin increased food intake and stabilized host weight when untreated TB controls were not eating and were losing weight. When daily insulin administration was started at an early stage of tumor growth and continued until death, there was again significant enhancement of host weight and food intake. Heart and adrenal weights were significantly reduced in insulin-treated TB animals. Tumor growth was not stimulated by insulin treatment. Survival time was slightly reduced in TB rats treated with long-term insulin. Survival time in TB rats randomized to insulin during late cachectic decline was not different from untreated TB controls. Insulin did not have any measurable effect on energy expenditure or the motor activity compartment of energy expenditure in either TB or NTB rats. Insulin treatment can reverse experimental cancer cachexia. It is a nutritional therapy which preferentially feeds the host over the tumor. As yet, its beneficial effects have not prolonged survival of tumor-bearing animals.

Animals↗

PubMed1984

Hypothyroidism abolishes the hyperdynamic phase and increases susceptibility to sepsis.

To evaluate the role of thyroid hormones in sepsis, 250-400 g rats were surgically thyroidectomized and 2-6 weeks later sepsis was produced by cecal ligation and puncture (CLP). In normal rats, total body O2 consumption (VO2) increased by 12.8% (P less than 0.05) in early sepsis (6 hr after CLP) and decreased slightly in late sepsis (16 hr after CLP). In hypothyroid (HT) rats, VO2 was depressed by 19.8% (P less than 0.05) in early sepsis and further decreased to 46.7% (P less than 0.001) of preoperative levels in late sepsis. Hepatic blood flow increased in early sepsis in normal rats but was unchanged in HT rats. The normal hyperglycemic response to early sepsis was also absent in HT rats. The respiratory control ratio (RCR) of isolated mitochondria with succinate was not increased in HT rats in early sepsis. In late sepsis, hypothyroid animals showed further decreases in VO2 and mitochondrial RCR, and, in contrast to normal rats, showed no change in blood glucose levels. Survival (5 days) following late sepsis in normal, HT, and HT rats given daily ip injections of thyroxine (30 micrograms/kg) were 65.2% (15/23), 30% (6/20) (P less than 0.025), and 77.1% (14/18), respectively. Thus, absence of thyroid hormone abolishes the hyperdynamic phase of sepsis and significantly increases mortality in sepsis, and thyroxine replacement following thyroidectomy prevents the increased mortality from sepsis.

Animals↗

PubMed1984

Contribution of inert mass to experimental cancer cachexia in rats.

An inert artificial tumor (AFT) was inflated in male F344 rats to simulate, experimentally, the growth in mass of large transplantable tumors that produce cachexia. The AFT depressed host weight gain and skeletal muscle mass up to 30% and food intake up to 20% of the depression induced by tumors of comparable size. When the growth rate of the AFT was low, there was no depression of food intake. Work-induced hypertrophy of skeletal muscles, as assessed by a gastrocnemius tenotomy model, was approximately equal to that of normal, tumor-bearing, and AFT-bearing animals. The AFT elevated host total energy expenditure by 12.5% and compartment-of-energy expenditure attributable to motor activity by 10.5%. The elevation of energy expenditure accounted for most of the depression of weight gain of AFT-bearing animals below that of intact animals. The large mass of most transplantable tumors leads to an overestimate of the malignant tissue-depletive effects of tumor and an under-estimate of the asthenic effects.

Animals↗

PubMed1979

Patterns of peptide synthesis in senescent and presenescent human fibroblasts.

Peptide production in senescent and presenescent human foreskin fibroblasts was measured using 2-dimensional polyacrylamide gel electrophoresis. This procedure permits the visualization of a cohort of the major peptides being produced. Among this cohort of over 500 peptides only two were found to differ in relative amount in that more was being produced in senescent cells. This difference was confirmed by measurements of the relative intensity of the peptide spot. This difference was senescent cell-specific and not due to the differences in rate of growth of senescent and non-senescent cells.

Cell Differentiation↗

PubMedDate not supplied

Body cell mass in cancer-bearing and anorexic patients.

We used a sensitive whole body counter which measures potassium-40 (40K) to determine total body potassium and to estimate body cell mass (BCM) in 104 previously untreated patients with upper gastrointestinal malignancies, 233 normal volunteers, and 18 patients with anorexia nervosa. BCM was greater in normal males than in females. In both normal males and females, the BCM tended to decrease with age, both as an absolute measure and as a percentage of body weight. Anorexia nervosa patients experienced marked weight loss (30.5%), and had significant depletion of absolute BCM, but exhibited relative sparing of BCM as indicated by a rise in BCM as a percentage of body weight. This may reflect a normal adaptation and predominant fat utilization in chronic malnutrition. The cancer patients, on the other hand, had significant weight loss (12.7% for females, 13.9% for males) and demonstrated a proportional decline in BCM, with no change in BCM as a percentage of body weight. These findings support the contention that, in the cancer-bearing patient, weight loss consists of a significant depletion of both fat and BCM. The challenge to the clinicians caring for cancer patients is repletion of this supremely functional body compartment.

Adult↗