GRP78 promoter polymorphism rs391957 as potential predictor for clinical outcome in gastric and colorectal cancer patients

BACKGROUND

Recently, the analysis of gastric and colorectal tumor specimens determined that 78-kiloDalton glucose-regulated protein (GRP78), an endoplasmic reticulum chaperone, up-regulation serves as an efficient mechanism protecting cells against apoptosis and can confer drug resistance. We tested whether functional polymorphisms within the GRP78 gene are related to clinical outcome in gastric and colorectal cancer (CRC) patients.

PATIENTS AND METHODS

Blood samples of 234 stage II/III CRC patients at the University of Southern California (USC) and formalin-fixed paraffin-embedded tissues of 137 patients with localized gastric adenocarcinoma (GA) at USC and Memorial Sloan-Kettering Cancer Centers were obtained. GRP78 polymorphisms analyzed on germline DNA were correlated with clinical outcome using univariate and multivariate analyses.

RESULTS

GA patients with the combined GRP78 rs391957 C/T and T/T genotype were at higher risk for tumor recurrence and death [hazard ratio (HR) 2.61; P < 0.001 and HR 3.17; P < 0.001, respectively], than those with C/C. These findings were subsequently tested in a CRC cohort where patients with the homozygous T/T genotype were at highest risk for tumor recurrence (HR 2.61; P = 0.015). The results remained significant after adjusting for clinicopathologic determinants.

CONCLUSION

These data provide the first evidence that the GRP78 rs391957 polymorphism can predict clinical outcome in localized GA and locally advanced CRC patients.

A basic smell test is as sensitive as a dopamine transporter scan: comparison of olfaction, taste and DaTSCAN in the diagnosis of Parkinson's disease

AIM

To evaluate relationship between odour identification, taste threshold, dopamine transporter scan (DaTSCAN) and motor function in early Parkinson's disease (PD) and their diagnostic accuracy.

METHODS

Seventy-three patients with early parkinsonism were evaluated by the Unified Parkinson's Disease Rating Scale (UPDRS), DaTSCAN, electrogustometry (EGM) threshold and University of Pennsylvania Smell Identification Test (UPSIT). Olfactory Event-Related potentials (OERP) were performed on 49 patients. At follow-up (mean 15.3 months), patients were diagnosed as 'PD' or 'non-PD'. DaTSCAN images were assessed visually and semi-quantitatively by QuantiSPECT.

RESULTS

The sensitivity of UPSIT (86%) was not significantly different from that of the DaTSCAN (92%). UPSIT correlated moderately with DaTSCAN uptake (r = 0.44; P < 0.005) and UPDRS score (r = 0.43; P < 0.05) and weakly with symptom duration (r = 0.25; P < 0.05). In the PD group, OERP showed increased latency but no change in amplitude and no correlation with DaTSCAN. EGM thresholds were impaired in 22% of the PD group but they did not correlate with any other test parameters. DaTSCAN-UPSIT discordance was found in nine patients with PD, but neither was diagnostically superior.

CONCLUSION

Our patients with early PD have a frequent and severe olfactory deficit that correlates with disease severity, symptom duration and DaTSCAN but not EGM. The sensitivities of UPSIT and DaTSCAN are high at 86% and 92%, respectively. Although DaTSCAN is superior for 'localization', UPSIT is considerably 'cheaper', and neither is disease specific. EGM threshold impairment in PD is independent of the smell deficit, and probably signifies advanced disease.

AMP-activated protein kinase (AMPK) activation regulates in vitro bone formation and bone mass

Adenosine 5'-monophosphate-activated protein kinase (AMPK), a regulator of energy homeostasis, has a central role in mediating the appetite-modulating and metabolic effects of many hormones and antidiabetic drugs metformin and glitazones. The objective of this study was to determine if AMPK can be activated in osteoblasts by known AMPK modulators and if AMPK activity is involved in osteoblast function in vitro and regulation of bone mass in vivo. ROS 17/2.8 rat osteoblast-like cells were cultured in the presence of AMPK activators (AICAR and metformin), AMPK inhibitor (compound C), the gastric peptide hormone ghrelin and the beta-adrenergic blocker propranolol. AMPK activity was measured in cell lysates by a functional kinase assay and AMPK protein phosphorylation was studied by Western Blotting using an antibody recognizing AMPK Thr-172 residue. We demonstrated that treatment of ROS 17/2.8 cells with AICAR and metformin stimulates Thr-172 phosphorylation of AMPK and dose-dependently increases its activity. In contrast, treatment of ROS 17/2.8 cells with compound C inhibited AMPK phosphorylation. Ghrelin and propranolol dose-dependently increased AMPK phosphorylation and activity. Cell proliferation and alkaline phosphatase activity were not affected by metformin treatment while AICAR significantly inhibited ROS 17/2.8 cell proliferation and alkaline phosphatase activity at high concentrations. To study the effect of AMPK activation on bone formation in vitro, primary osteoblasts obtained from rat calvaria were cultured for 14-17days in the presence of AICAR, metformin and compound C. Formation of 'trabecular-shaped' bone nodules was evaluated following alizarin red staining. We demonstrated that both AICAR and metformin dose-dependently increase trabecular bone nodule formation, while compound C inhibits bone formation. When primary osteoblasts were co-treated with AICAR and compound C, compound C suppressed the stimulatory effect of AICAR on bone nodule formation. AMPK is a alphabetagamma heterotrimer, where alpha is the catalytic subunit. RT-PCR analysis of AMPK subunits in ROS17/2.8 osteoblastic cells and in mouse tibia showed that the AMPKalpha1 subunit is the dominant isoform expressed in bone. We analysed the bone phenotype of 4month-old male wild type (WT) and AMPKalpha1-/- KO mice using micro-CT. Both cortical and trabecular bone compartments were smaller in the AMPK alpha1-deficient mice compared to the WT mice. Altogether, our data support a role for AMPK signalling in skeletal physiology.

Bart's syndrome

A new-born girl presented with congenital absence of skin on the right leg and nail abnormalities. On second day of life, she developed multiple blistering skin lesions and died on seventeenth day of life. A positive family history of two other siblings, one male and one female who had blistering skin lesions and died within one and a half month of birth, was present. The diagnosis of Bart's syndrome was made on clinical presentation, family history and skin biopsy.

Recognising anaemia and malnutrition in vascular patients with critical limb ischaemia

INTRODUCTION

Anaemia is a common problem in surgical patients. Patients with critical limb ischaemia (CLI) suffer chronic inflammation, repeated infection, require intervention, and can have a protracted hospital stay. The aims of this study were to assess anaemia and nutritional status in patients presenting with CLI.

PATIENTS AND METHODS

Two observational studies were undertaken, initially a retrospective series of 27 patients with CLI. Patient demographics, clinical details, transfusion status and in-patient laboratory haemoglobin values (Hb) were recorded. In a prospective series of 32 patients, laboratory markers to identify the cause for anaemia were assessed. Further nutritional status was assessed by records of height, weight, body mass index and a validated scoring system.

RESULTS

In the retrospective series, 15 patients (56%) were anaemic. Ten (37%) were transfused a median of 2 units (range, 2-13), a total of 35 units. Patients who were transfused had lower Hb on admission (P = 0.0019), most were anaemic on admission (90%). At discharge, most patients were anaemic (n = 23; 83%). In the prospective series of 32 patients, 20 (63%) were anaemic. Nutritional assessment was performed on 18, only seven patients were scored undernourished. This was increased to 23 by an independent assessor. Anaemia was associated with malnutrition (n = 17; P = 0.049) and an increased hospital stay (mean 25 days [SD 16] vs mean 12 days [SD 8], P = 0.0125; total 513 vs 144 bed days).

CONCLUSIONS

Anaemia and poor nutrition are common and not recognised in vascular patients presenting with critical limb ischaemia. Anaemia is associated with and increased length of hospital stay.

Matrix metalloproteinase 13-deficient mice are resistant to osteoarthritic cartilage erosion but not chondrocyte hypertrophy or osteophyte development

OBJECTIVE

To investigate the role of matrix metalloproteinase 13 (MMP-13; collagenase 3) in osteoarthritis (OA).

METHODS

OA was surgically induced in the knees of MMP-13-knockout mice and wild-type mice, and mice were compared. Histologic scoring of femoral and tibial cartilage aggrecan loss (0-3 scale), erosion (0-7 scale), and chondrocyte hypertrophy (0-1 scale), as well as osteophyte size (0-3 scale) and maturity (0-3 scale) was performed. Serial sections were stained for type X collagen and the MMP-generated aggrecan neoepitope DIPEN.

RESULTS

Following surgery, aggrecan loss and cartilage erosion were more severe in the tibia than femur (P<0.01) and tibial cartilage erosion increased with time (P<0.05) in wild-type mice. Cartilaginous osteophytes were present at 4 weeks and underwent ossification, with size and maturity increasing by 8 weeks (P<0.01). There was no difference between genotypes in aggrecan loss or cartilage erosion at 4 weeks. There was less tibial cartilage erosion in knockout mice than in wild-type mice at 8 weeks (P<0.02). Cartilaginous osteophytes were larger in knockout mice at 4 weeks (P<0.01), but by 8 weeks osteophyte maturity and size were no different from those in wild-type mice. Articular chondrocyte hypertrophy with positive type X collagen and DIPEN staining occurred in both wild-type and knockout mouse joints.

CONCLUSION

Our findings indicate that structural cartilage damage in a mouse model of OA is dependent on MMP-13 activity. Chondrocyte hypertrophy is not regulated by MMP-13 activity in this model and does not in itself lead to cartilage erosion. MMP-13 deficiency can inhibit cartilage erosion in the presence of aggrecan depletion, supporting the potential for therapeutic intervention in established OA with MMP-13 inhibitors.

The etiology of infectious corneal ulceration in Sierra Leone

The microbial etiology of infectious corneal ulceration in Sierra Leone has been investigated. Patients either presenting to district health centers or encountered on rural surveillance expeditions with suspected infectious ulcerative keratitis were recruited into the study. Infectious corneal ulceration was defined as clinical evidence of corneal infection with epithelial defect with or without hypopyon. Cultures were obtained in a standard fashion and subsequent microbial analysis performed on all specimens. Seventy-three (73) cases of suspected infectious ulcerative keratitis were obtained between January 2005 and January 2006. The most commonly isolated organisms from microbial cultures of infected eyes were Gram-negative bacteria (45.2%), Gram-positive bacteria (37.0%), and fungal species (35.6%). Mixed bacterial and fungal organisms were isolated from ten eyes (13.7%) and no organisms were isolated from four eyes (5.5%). There is a high incidence of Gram-negative and fungal ulcerative keratitis in the population studied in Sierra Leone. Empirical therapy for corneal ulceration in this region should be aimed towards treatment of bacterial, fungal, and mixed infections.

Medical mortality in Pakistan: experience at a tertiary care hospital

AIM

To acquire systematic data on the causes of hospital mortality in Pakistan, a developing country with scant mortality records.

STUDY DESIGN

Retrospective review of death certificates and hospital charts of patients dying on general and specialty medical services at our hospital during one calendar year.

RESULTS

Of a total 10,590 admissions, 657 (6.2%) died in hospital. The deceased included 357 (54.4%) males and 299 (45.6%) females, with a collective median age of 63 years and mean length of stay 6.71 days (median 4 days, range 1-56 days). Primary cause of death was categorised as infectious (21.2%), pulmonary (17.2%), cancer related (15.7%), cardiovascular (12.6%), gastrointestinal and hepatic (10.8%), neurological (11.4%) and miscellaneous (11.1%). Within each category, the most common diagnoses were septicaemia (76.9% of infectious cases), pneumonia (55.7% of pulmonary cases), myocardial infarction (40.9% of cardiovascular), intracranial haemorrhage (37.3% of neurological), and cirrhosis (45.0% of gastrointestinal). There were multiple causes among malignant disorders with no single cause dominating. Patients with cardiovascular and pulmonary deaths tended to be older than the median age (p = 0.001), while patients with gastrointestinal and cancer related deaths tended to be younger than the median age (p = 0.001). Length of stay did not differ significantly among the various subgroups. About a quarter (26.4%) deaths occurred within 24 h of admission.

CONCLUSIONS

Infections, including septicaemia and pneumonia, are the leading causes of hospital mortality in our setting, followed by malignancy and cardiovascular causes. The overall mortality rate is comparable to published mortality data from other hospital settings.