Serum resistin is associated with C-reactive protein & LDL cholesterol in type 2 diabetes and coronary artery disease in a Saudi population

AIMS

Resistin is an adipocyte-derived factor implicated in obesity-associated type 2 diabetes (T2DM). This study examines the association between human serum resistin, T2DM and coronary heart disease.

METHODS

One hundred and fourteen Saudi Arabian patients (male: female ratio 46:68; age 51.4 (mean +/- SD)11.7 years; median and range: 45.59 (11.7) years and BMI: 27.1 (mean +/- SD) 8.1 Kgm2 median and range: 30.3 (6.3) were studied. Serum resistin and C-reactive protein (CRP), a marker of inflammation CRP levels, were measured in all subjects. (35 patients had type 2 diabetes mellitus (T2DM); 22 patients had coronary heart disease (CHD).

RESULTS

Serum resistin levels were 1.2-fold higher in type 2 diabetes and 1.3-fold higher in CHD than in controls (p = 0.01). In addition, CRP was significantly increased in both T2DM and CHD patients (p = 0.007 and p = 0.002 respectively). The use of regression analysis also determined that serum resistin correlated with CRP levels (p = 0.04, R2 0.045).

CONCLUSION

The findings from this study further implicate resistin as a circulating protein associated with T2DM and CHD. In addition this study also demonstrates an association between resistin and CRP, a marker of inflammation in type 2 diabetic patients.

Epidermal growth factor receptor expression in anal canal carcinoma

Most anal canal carcinomas (ACCs) are squamous cell carcinomas (SCCs). SCCs in other tumor sites strongly express epidermal growth factor receptors (EGFRs), the inhibition of which might result in favorable changes in tumor growth. A review of the published scientific literature reveals no information regarding the expression of EGFR in ACCs. Therefore, we obtained archived pathology samples from ACC biopsies and examined the frequency and level of expression of EGFR and other cell surface and cell cycle markers. The 21 samples studied universally and strongly expressed EGFR and were negative for HER-2. Clinical studies of EGFR inhibitors in advanced ACC are warranted.

Differential gene expression profile reveals deregulation of pregnancy specific beta1 glycoprotein 9 early during colorectal carcinogenesis

Background

APC (Adenomatous polyposis coli) plays an important role in the pathogenesis of both familial and sporadic colorectal cancer. Patients carrying germline APC mutations develop multiple colonic adenomas at younger age and higher frequency than non-carrier cases which indicates that silencing of one APC allele may be sufficient to initiate the transformation process.

Methods

To elucidate the biological dysregulation underlying adenoma formation we examined global gene expression profiles of adenomas and corresponding normal mucosa from an FAP patient. Differential expression of the most significant gene identified in this study was further validated by mRNA in situ hybridization, reverse transcriptase PCR and Northern blotting in different sets of adenomas, tumours and cancer cell lines.

Results

Eighty four genes were differentially expressed between all adenomas and corresponding normal mucosa, while only seven genes showed differential expression within the adenomas. The first group included pregnancy specific β-1 glycoprotein 9 (PSG9) (p < 0.006). PSG9 is a member of the carcinoembryonic antigen (CEA)/PSG family and is produced at high levels during pregnancy, mainly by syncytiotrophoblasts. Further analysis of sporadic and familial colorectal cancer confirmed that PSG9 is ectopically upregulated in vivo by cancer cells. In total, deregulation of PSG9 mRNA was detected in 78% (14/18) of FAP adenomas and 75% (45/60) of sporadic colorectal cancer cases tested.

Conclusion

Detection of PSG9 expression in adenomas, and at higher levels in FAP cases, indicates that germline APC mutations and defects in Wnt signalling modulate PSG9 expression. Since PSG9 is not found in the non-pregnant adult except in association with cancer, and it appears to be an early molecular event associated with colorectal cancer monitoring of its expression may be useful as a biomarker for the early detection of this disease.

Expression of cell adhesion molecules in oesophageal carcinoma and its prognostic value

Oesophageal carcinoma remains a disease of poor prognosis. Surgical cure rates are compromised by the fact that most patients are diagnosed at a late stage of disease because of the delayed onset of symptoms, by which time metastases and organ infiltration may have already occurred. Thus, invasion and metastases play a key role in influencing patient survival, and the search for novel treatments may therefore hinge on gaining insight into the mechanisms controlling these processes. It has been established that the initial step in the metastatic cascade is the detachment of tumour cells from the primary tumour via dysregulation of normal cell-cell and cell-matrix interactions. Distinct proteins known as cell adhesion molecules (CAMs) mediate these interactions. In recent years, a plethora of information has contributed to the in depth understanding of these molecules. This review provides a brief description of five families of CAMs (cadherins, integrins, CD44, immunoglobulin superfamily, and selectins) and highlights their altered expression in relation both to prognosis and tumour behaviour in squamous cell carcinoma and adenocarcinoma of the oesophagus.

Isolated splenic tuberculosis

Tuberculosis isolated to the spleen is a rare clinical entity particularly in the non-HIV-positive patient population. In the four patients described, two presented with thrombocytopenia; in two patients the condition was diagnosed serendipitously at laparotomy undertaken for abdominal trauma.

Aberrations in the mismatch repair genes and the clinical impact on oesophageal squamous carcinomas from a high incidence area in South Africa

AIMS

To investigate the incidence of genetic aberrations in the DNA repair genes in a cohort of oesophageal cancers.

METHODS

One hundred oesophagectomy samples of squamous cell carcinoma were studied. Normal and tumour DNA were isolated using a standard phenol/chloroform extraction procedure. Six recommended microsatellite loci with high informativity were analysed. The following markers were used: D2S123 (2p), D3S659 (3p), D3S1255 (3p), Bat 25 (4q), Bat 26 (2p), and Bat 40 (1p). The results were analysed using software attached to an automated DNA sequencer. The molecular data were then correlated with clinicopathological parameters.

RESULTS

The incidence of microsatellite instability and loss of heterozygosity was very low. There was no significant correlation between the clinicopathological and molecular data. However, D2S123 genetic abnormalities were seen more frequently in both moderately and well differentiated tumours than in poorly differentiated tumours (p = 0.033). Follow up data were available for only 67 of the 100 patients. Fifty patients were alive and 17 patients had died.

CONCLUSION

Low frequencies of genetic aberrations in these mismatch repair loci are found in squamous carcinomas of the oesophagus from a high incidence area in South Africa.

Aberrations in the mismatch repair genes and the clinical impact on oesophageal squamous carcinomas from a high incidence area in South Africa

AIMS

To investigate the incidence of genetic aberrations in the DNA repair genes in a cohort of oesophageal cancers.

METHODS

One hundred oesophagectomy samples of squamous cell carcinoma were studied. Normal and tumour DNA were isolated using a standard phenol/chloroform extraction procedure. Six recommended microsatellite loci with high informativity were analysed. The following markers were used: D2S123 (2p), D3S659 (3p), D3S1255 (3p), Bat 25 (4q), Bat 26 (2p), and Bat 40 (1p). The results were analysed using software attached to an automated DNA sequencer. The molecular data were then correlated with clinicopathological parameters.

RESULTS

The incidence of microsatellite instability and loss of heterozygosity was very low. There was no significant correlation between the clinicopathological and molecular data. However, D2S123 genetic abnormalities were seen more frequently in both moderately and well differentiated tumours than in poorly differentiated tumours (p = 0.033). Follow up data were available for only 67 of the 100 patients. Fifty patients were alive and 17 patients had died.

CONCLUSION

Low frequencies of genetic aberrations in these mismatch repair loci are found in squamous carcinomas of the oesophagus from a high incidence area in South Africa.

Expression profiling by microarrays in colorectal cancer (Review)

Genome-wide gene profiling studies using microarrays have the potential to improve diagnosis and treatment of human cancers. Microarrays have identified many genes that are deregulated in colorectal cancer compared to normal tissue. Groups of genes that are predictive of tumor stage or presence of metastases, hence putatively associated with cancer progression have also been revealed. Microarray studies have identified genes whose expression are impacted by chemotherapies for colorectal cancer, thus could potentially be used to predict response to treatments. Unique gene expression profiles have also been used to classify metastases of uncertain origin. The wide application of microarrays generates exciting prospects in translational research. However, to date overlaps of candidate gene lists associated with specific clinical/biological phenotypes remain disturbingly poor between studies. Overfitting, bias, reporting of only the best results, and fidelity of probe annotations could present limitations for the interpretation of results shown in microarray publications. Making raw data from these microarray experiments publicly available for analysis by other investigators using different analytical algorithms or for in silico studies may facilitate the most thorough mining of data from these expensive studies. Validations of the results using other more precise techniques and at the biological level represent critical follow-up goals for microarray studies.

Intraductal papillary mucinous neoplasm of the pancreas in a patient with attenuated familial adenomatous polyposis

A 67 year old man with a clinical diagnosis of attenuated familial adenomatous polyposis (AFAP) and a past history of synchronous colon cancers in the transverse colon was also found to have an intraductal papillary mucinous neoplasm (IPMN) of the pancreas. In addition, several foci of heterotopic gastric oxyntic mucosa were noted in the duodenum, interspersed with flat and polypoid adenomas. The duodenal adenomas showed low grade dysplasia, loss of adenomatous polyposis coli (APC) protein expression, but retention of beta catenin staining, localised to the nucleus and cytoplasm. The IPMN in the pancreas showed an identical immunohistochemical profile to the duodenal adenomas. The heterotopic gastric foci in the duodenum were negative for the APC protein, and beta catenin staining was membranous in location. Although the patient did not show germline truncating APC mutations or mutations in the MYH gene, the past history, clinical features, and immunohistochemical profile of the various lesions suggest strongly that the IPMN is part of the spectrum of lesions encountered in AFAP. Whether the heterotopic oxyntic gastric mucosa in the duodenum is also related is unclear, but it may represent a forme fruste of fundic gland polyps.

Spindle cell pancreatic endocrine tumor associated with Cushing's syndrome

A 59-yr old female presented with Cushing's syndrome due to ectopic ACTH production. At the time of initial diagnosis an obvious source for the Cushing's syndrome was not found and the patient was treated with bilateral adrenalectomy. Three years later she presented with hyperpigmentation and evidence of ACTH overproduction. This time a CT scan localized a mass to the tail of the pancreas and a distal pancreatectomy was performed. The mass was composed of compact plump spindle cells arranged in interlacing fascicles, was well circumscribed, and did not display angioinvasion. Although isolated punctate foci of necrosis were noted, the overall mitotic count was 1 per 10 high power fields. Immunohistochemistry showed the tumor to be positive for chromogranin, synaptophysin, and ACTH. This case highlights an unusual histological variant of pancreatic endocrine tumor (PET), namely, one composed almost exclusively of interlacing spindle-shaped cells. This raises a wide differential diagnosis and the use of immunohistochemistry is required to arrive at the correct diagnosis. ACTH-producing PET are usually aggressive lesions with metastases at the time of presentation and aggressive biological behavior. However, this case was characterized by an indolent clinical course.

Pancreatic endocrine tumour with cytoplasmic keratin whorls. Is the term "rhabdoid" appropriate?

A 50 year old woman presented with acute abdominal pain accompanied by nausea and vomiting and was found to have a mass in the head of the pancreas by imaging. The clinical impression was of a pancreatic carcinoma and a Whipple's procedure was performed. Microscopic examination of the tumour showed it to be a low grade neuroendocrine carcinoma arranged in a tubuloacinar or tubulopapillary pattern, and composed of cells harbouring very prominent intracytoplasmic inclusions. These inclusions varied in appearance from being pale pink and hyaline in quality to more eosinophilic and globular causing displacement of the nucleus. Ultrastructural examination showed typical paranuclear aggregates of intermediate filaments. Inclusions of this type have been described previously as "signet ring like" and "rhabdoid". It was felt that the inclusions more closely resemble the fibrous bodies that are seen in pituitary adenomas. In addition, it is suggested that both signet ring and rhabdoid are not appropriate because they do not reflect histogenesis and are not necessarily reflective of tumour biology. It is suggested that the term "cytokeratin aggresomes" should be used to describe this distinctive phenotype.

Association of simple anthropometric measures of obesity with visceral fat and the metabolic syndrome in male Caucasian and Indo-Asian subjects

AIMS

The aims of this study were first, to investigate the relationship between simple anthropometric measures of obesity with visceral fat as assessed by a single slice magnetic resonance imaging (MRI)-scan in patients attending a hospital clinic. Second, to determine which anthropometric measure best relates to the adverse metabolic profile of the metabolic syndrome.

METHODS

Forty-one male subjects [body mass index (BMI): 30.2 + 5.8 kg/m(2), age: 50.3 + 13.6 years] were studied by MRI-scan to measure visceral fat at L4/L5 level and to investigate its relationship with simple anthropometric measures. Second, we studied 83 male subjects to determine which anthropometric measure best predicts the metabolic complications (using the ATPIII criteria) of obesity in the setting of a hospital clinic.

RESULTS

Waist circumference was the best anthropometric measurement that correlated with MRI-visceral fat mass assessed at L4/L5 in 41 subjects who had an MRI scan (P = 0.0001, r(2) = 0.36, beta = 0.56) amongst variables which also included age, BMI, sagittal diameter, diabetes and ethnicity. Stepwise multiple regression analysis showed sagittal diameter (P = 0.001, r(2) = 0.4, beta = 0.406), age (P = 0.003, beta = 0.271) and waist circumference (P = 0.012, beta = 0.297) were the best predictors of the adverse metabolic profile of the metabolic syndrome in all 83 male subjects amongst BMI, waist-hip ratio (WHR), ethnicity and diabetes-related factors.

CONCLUSIONS

Waist circumference is a simple anthropometric parameter that best correlates with single slice MRI-scan, but sagittal diameter (measured using abdominal calipers) better predicts the adverse metabolic profile of the metabolic syndrome. Although there is considerable variation in abdominal fat topography between ethnic groups, and also within populations, sagittal diameter assessment is a technique that is simple and best predicts the metabolic syndrome.

Clear cell (glycogen-rich) gastric adenocarcinoma

Clear cells have been described in many tumors of varying differentiation. Although clear cell carcinoma is well-recognized in the lower urinary and female genital tracts, its occurrence in the gastrointestinal tract and related structures is uncommon. There have been only a few case reports and small series reporting this morphologic phenomenon in the stomach, colon, and biliary tract. Clear cell carcinoma of the endometrium has been associated with poor prognosis, but the prognostic significance of clear cells in gastric adenocarcinoma is unknown. Herein we describe three cases of clear cell, glycogen-rich, gastric adenocarcinoma and evaluate the frequently used classification systems for gastric cancer. Two tumors showed a tubulopapillary pattern and one showed a predominantly diffuse sheet-like growth. The proliferation (MIB) index in all cases was approximately 20%. Only case 1 showed focal staining for alpha-fetoprotein and both cases 1 and 2 showed focal carcinoembryonic antigen reactivity. In conclusion, we describe three cases of clear cell gastric carcinoma that presented as high-stage disease.

Sertoli cell nodules in the undescended testis: a histochemical, immunohistochemical, and ultrastructural study of hyaline deposits

AIMS

To document the morphology, immunohistochemical staining properties, and ultrastructural features of hyaline material in Sertoli cell nodules of undescended testis and contrast them with those of sex cord tumour with annular tubules (SCTAT), which is histologically similar. To highlight the need to distinguish these nodules from other Sertoli cell hyperplasias, such as intratubular Sertoli cell proliferations, which occur in specific clinical contexts.

MATERIALS/METHODS

A retrospective study of 46 orchidectomy specimens from cryptorchid testes, 27 of which contained Sertoli cell nodules. Special histochemical stains, immunohistochemical stains for type IV collagen and fibronectin, and ultrastructural examination of the hyaline material were performed using tissue from paraffin wax embedded tissue blocks.

RESULTS

The hyaline deposits in SCTAT and Sertoli cell nodules had similar staining patterns-periodic acid Schiff (PAS) and PAS-diastase positivity with variable staining of Martius scarlet blue and Masson trichrome. Type IV collagen immunoreactivity was seen in hyaline areas, although fibronectin was negative. Electron microscopy of hyaline areas confirmed a compact matrix identical to components of the basement membrane in the adjacent seminiferous tubules.

CONCLUSION

This study describes an unusual form of Sertoli cell proliferation in undescended testes, which must be distinguished from Sertoli cell tumours and other forms of proliferation. In addition, the hyaline material within Sertoli cell nodules in the cryptorchid testis is histochemically, immunohistochemically, and ultrastructurally consistent with both matrix and fibrous components of seminiferous tubule basement membranes. Increased production of basement membrane material, with subsequent invagination into tubules, is the most likely origin of this material.

11beta-hydroxysteroid dehydrogenase type 1 activity in lean and obese males with type 2 diabetes mellitus

Glucocorticoids play an important role in the pathogenesis of obesity and insulin resistance. Impaired conversion of cortisone (E) to cortisol (F) by the type 1 isoenzyme of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) in obesity may represent a protective mechanism preventing ongoing weight gain and glucose intolerance. We have studied glucocorticoid metabolism in 33 male subjects with type 2 diabetes mellitus [age, 44.2 +/- 13 yr; body mass index (BMI), 31.1 +/- 7.5 kg/m(2) (mean +/- sd)] and 38 normal controls (age, 41.4 +/- 14 yr; BMI, 38.2 +/- 12.8 kg/m(2)). Circulating F:E ratios were elevated in the diabetic group and correlated with serum cholesterol and homeostasis model assessment-S. There was no difference in 11beta-HSD1 activity between diabetic subjects and controls. In addition, 11beta-HSD1 activity was unaffected by BMI in diabetic subjects. However, in control subjects, increasing BMI was associated with a reduction in the urinary tetrahydrocortisol+5alpha-tetrahydrocortisol:tetrahydrocortisone ratio (P < 0.05) indicative of impaired 11beta-HSD1 activity. The degree of inhibition correlated tightly with visceral fat mass. Changes in 11beta-HSD1 activity could not be explained by circulating levels of adipocytokines. Impaired E to F metabolism in obesity may help preserve insulin sensitivity and prevent diabetes mellitus. Failure to down-regulate 11beta-HSD1 activity in patients with diabetes may potentiate dyslipidemia, insulin resistance, and obesity. Inhibition of 11beta-HSD1 may therefore represent a therapeutic strategy in patients with type 2 diabetes mellitus and obesity.

Influence of apoptosis on neurological outcome following traumatic cerebral contusion

Object. Apoptosis has increasingly been implicated in the pathobiology of traumatic brain injury (TBI). The present study was undertaken to confirm the presence of apoptosis in the periischemic zone (PIZ) of traumatic cerebral contusions and to determine the role of apoptosis, if any, in neurological outcome.

Methods. Brain tissue harvested at Wentworth Hospital from the PIZ in 29 patients with traumatic supratentorial contusions was compared with brain tissue resected in patients with epilepsy. Immunohistochemical analyses were performed on the tissues to see if they contained the apoptosis-related proteins p53, bcl-2, bax, and caspase-3. The findings were then correlated to demographic, clinical, surgical, neuroimaging, and outcome data.

In the PIZ significant increases of bax (18-fold; p < 0.005) and caspase-3 (20-fold; p < 0.005) were recorded, whereas bcl-2 was upregulated in only 14 patients (48.3%; 2.9-fold increase) compared with control tissue. Patients in the bcl-2—positive group exhibited improved outcomes at the 18-month follow-up examination despite an older mean age and lower mean admission Glasgow Coma Scale score (p < 0.03). Caspase-3 immunostaining was increased in those patients who died (Glasgow Outcome Scale [GOS] Score 1, 12 patients) when compared with those who experienced a good outcome (GOS Score 4 or 5, 17 patients) (p < 0.005). Regression analysis identified bcl-2—negative status (p < 0.04, odds ratio [OR] 5.5; 95% confidence interval [CI] 1.1–28.4) and caspase-3—positive status (p < 0.01, OR 1.4, 95% CI 1.1—1.8) as independent predictors of poor outcome. No immunostaining for p53 was recorded in the TBI specimens.

Conclusions. The present findings confirm apoptosis in the PIZ of traumatic cerebral contusions and indicate that this form of cell death can influence neurological outcome following a TBI.

Pancreatic endocrine tumors: an update

The morphology of pancreatic endocrine tumors (PETs) is similar to that of endocrine tumors elsewhere in the body. PETs are usually encountered in adults. They may be clinically functional and associated with various syndromes related to hormone excess. However, it must be remembered that absence of obvious clinical symptoms may not necessarily reflect true lack of clinical function, and subtle clinical manifestations may be missed. Current thinking indicates that PETs arise from totipotential stem cells as well as preexisting endocrine cells. PETs may be hereditary or sporadic. The hereditary forms are associated with multiple endocrine neoplasia type 1 (MEN-1), von Hippel-Lindau syndrome, neurofibromatosis, and tuberous sclerosis. In sporadic PETs, the most consistent and recurring chromosomal abnormality is allelic loss of chromosome 11q, which includes the MEN-1 locus. Loss of a sex chromosome has been shown to be associated with metastasis, local invasion, and poor survival.

Modest weight loss and reduction in waist circumference after medical treatment are associated with favorable changes in serum adipocytokines

Modest weight loss if maintained is associated with significant metabolic benefits and reduction in cardiovascular risk. Adipose tissue secretes cytokines believed to contribute to the pathogenesis of insulin resistance and cardiovascular risk. We therefore observed the effect of modest weight loss on serum adipocytokines and their relationship with changes in anthropometric and metabolic parameters within a period of 6 months in the setting of a routine obesity hospital clinic after various medical treatments. In this prospective, nonrandomized, nonblinded observational study, patients were first given treatment (sibutramine or orlistat) as decided by the treating clinician and then allocated into 1 of 2 groups according to the treatment prescribed. The first group included 21 Caucasian nondiabetic female subjects, with a mean (+/-SD) age of 43 +/- 11 years and a mean body mass index (BMI) of 46 +/- 8.6 kg/m(2); subjects were treated with sibutramine 10 or 15 mg/d for weight loss. The second group included 20 Caucasian nondiabetic female subjects, mean age 42 +/- 9 years and mean BMI 45.2 +/- 5.2 kg/m(2); orlistat was introduced after 1 month on a low-fat (</=30%) diet in this group. Blood pressure and anthropometric measurements were performed before and after weight loss by a single observer. Serum glucose, insulin, lipid profile, C-reactive protein (CRP), resistin, leptin, and adiponectin were measured before and after weight loss on a fasting sample. After 6 months, the sibutramine group had a modest mean weight loss of 5.4% (P =.0001), and waist circumference was reduced by 4.5 +/- 1.4 cm. There was a decrease in serum resistin, leptin, and CRP levels, and a rise in serum adiponectin (P <.05). Change (%) (Delta) in BMI (DeltaBMI%) was associated with Deltainsulin(%) (P =.02, r = 0.53) and Deltaleptin(%) (P =.01, r = 0.58). Change in waist was associated with Deltainsulin(%) (P =.005, r = 0.75) and Deltaresistin(%) (P =.03, r = -0.55). The orlistat-treated group had a mean weight loss of 2.5%. Although this group did not show significant change in metabolic parameters, surprisingly there was a greater decrease of resistin (P =.02) associated with comparable (%) increase in adiponectin and (%) reduction of waist circumference and CRP. We conclude that modest weight loss (>5%) after medical treatment in a routine obesity hospital clinic is associated with improvements in insulin sensitivity and lipid profile. Modest weight loss is also associated with potentially favourably changes in serum adipocytokines, particularly in a rise of serum adiponectin. Reduction of waist circumference is associated with a change in serum resistin.

Gastric neuroendocrine carcinoma arising from heterotopic pancreatic tissue

An 85 year old man presented with symptoms of dyspepsia and increase in stool frequency of two months duration. Upper endoscopy revealed an ulcer and the biopsy was interpreted as carcinoma with endocrine features. A formal distal gastrectomy was planned, but intraoperatively, because of the patient's condition, a wedge resection was performed. Histology revealed a neuroendocrine tumour (grade 1), located mainly in the submucosa, which had caused mucosal attenuation and ulceration. Associated with the tumour and at its periphery was heterotopic pancreatic tissue composed of acini, ducts, and endocrine cells. The tumour was strongly positive for chromogranin and focally for synaptophysin. There was no associated chronic atrophic gastritis or G cell hyperplasia. A discrete focus of high grade neuroendocrine carcinoma (grade 3) within the typical (grade 1) neuroendocrine tumour was also present. This case illustrates a grade 1 neuroendocrine carcinoma, with a small grade 3 focus, arising within or intimately associated with heterotopic pancreatic tissue in the stomach. Although the two entities may be separate, their close topographical association favours the possibility of neuroendocrine carcinoma arising from the heterotopic pancreas. Pathologists should be aware of the occurrence of pancreatic heterotopia in the stomach and the association of carcinoma with it.