Association between EGF and VEGF functional polymorphisms and sporadic colorectal cancer in the Malaysian population

Growth factors are polypeptides that are critical for the initiation, progression, and metastasis of cancer. Most tumor cells are capable of synthesizing particular growth factors leading to constitutive pathway activation in these cells through autocrine signaling. Epidermal growth factor (EGF) is a potent mitogenic peptide that exerts direct effects on the proliferation and differentiation of tumor cells in carcinogenesis. By contrast, vascular endothelial growth factor (VEGF) is vital for the invasion and metastasis of neoplasms through the formation of new blood vessels from mature endothelial cells. In this study, we investigated the association between functional polymorphisms of both the EGF and VEGF genes and colorectal cancer (CRC) susceptibility. A total of 130 CRC patients and 212 healthy controls were recruited for this case-control study. Genotyping of genetic variants was conducted via real-time polymerase chain reaction (PCR) amplification with allele-specific TaqMan probes. None of the genotypes of the EGF +61 A>G and VEGF +936 C>T variants was significantly associated with CRC susceptibility among the Malaysian subjects evaluated (P > 0.05). The observed frequency distributions of the EGF +61 A>G polymorphism genotypes showed ethnic heterogeneity, which was not the case for the VEGF +936 C>T genotypes. In conclusion, no positive correlation between these functional polymorphisms and CRC risk was found in this Malaysian population. Studies of the EGF and VEGF genes and CRC susceptibility are scarce, and the results reported thus far differ from one population to another. Hence, more replication studies are warranted before any firm conclusions can be made.

NOD2/CARD15 variants in Malaysian patients with sporadic colorectal cancer

Colorectal cancer (CRC) is one of the most common types of cancer in both developed and developing countries. This disease is triggered by and progresses via the sequential accumulation of multiple genetic alterations. In addition, the interaction between low-penetrance genes and environmental factors can also increase the risk of developing CRC. Since inflammatory bowel diseases (IBDs) are one of the predisposing factors for CRC, IBD-related genes might, to a certain extent, be associated with cancer initiation. The nucleotide oligomerization domain 2/caspase activating recruitment domain 15 gene (NOD2/CARD15) is the most well-established gene to be associated with increased susceptibility to Crohn's disease. Thus, various studies have been performed to investigate the potential contribution of this gene to CRC risk. In this study, we aimed to determine the frequency of the Arg702Trp, Gly908Arg, 3020insC, Pro268Ser, and JW1 variants of NOD2/CARD15, and to investigate their association with CRC susceptibility. A total of 130 CRC patients and 212 healthy controls were recruited for this study. Subsequently, real-time polymerase chain reaction with TaqMan was performed for the genotyping of these NOD2/ CARD15 variants. None of the NOD2/CARD15 variants was statistically associated to CRC susceptibility in our Malaysian population. Our findings were remarkably similar to those of other Asian cohorts, which indicated that these NOD2/CARD15 variants exhibit genetic heterogeneity between Caucasian and Asian populations.

Lack of association between TYK2 and STAT3 genes and Crohn's disease in the Malaysian population

This study aimed to investigate the potential association of TYK2 and STAT3 genes with the susceptibility to Crohn's disease (CD) among Malaysians. DNA samples were obtained from 80 CD patients and 100 healthy controls. Polymerase chain reaction-restriction fragment length polymorphism methods were employed for genotyping, followed by statistical analysis. In our current study, none of the single nucleotide polymorphisms of either TYK2 or STAT3 was statistically associated with the susceptibility to CD in our local population (P > 0.05). In contrast, there was a statistically significant association between the G/G homozygotes of the STAT3 rs2293152 and the healthy control group (χ(2) = 6.229, P < 0.05). In conclusion, our study does not support the role of the TYK2 and STAT3 genes influencing CD susceptibility.

Co-inheritance of variants/mutations in Malaysian patients with Crohn's disease

Crohn's disease is a chronic, relapsing inflammatory bowel disease; it affects the mucosa and deeper layers of the digestive wall. Two Crohn's disease patients who carried the JW1 variant and two patients who carried the SNP5 variant were investigated for other co-inherited polymorphisms that could influence Crohn's disease development. Based on the sequencing results, a homozygous 5'-UTR-59 G to A variant in exon 1 (SNP6) was observed in a patient who carried SNP5, while a heterozygous SNP6 variant was detected in the other patient who carried SNP5. No other associated mutations or polymorphisms were detected in the two patients who carried the JW1 variant of the CARD15/NOD2 gene.

Analysis of major complications associated with arterial catheterisation

INTRODUCTION

Arterial catheterisation is used for continuous haemodynamic monitoring in patients undergoing surgery and in critical care units. Although it is considered a safe procedure, a major complication such as arterial occlusion and limb gangrene can occur.

OBJECTIVE

To determine the incidence, outcome and potential to avoid complications associated with arterial catheterisation.

METHODS

The number of arterial catheterisation was determined using an anaesthesiology and critical care medicine billing database over a period of 4 years (1 January 2003 to 31 December 2006). Possible major complications were identified from two hospital databases; all identified charts were screened and then reviewed by an expert panel that determined causation. A major complication was defined as requiring operative intervention and/or resulting in permanent harm.

RESULTS

15 (0.084%) major complications were identified among 17 840 instances of arterial catheterisation insertions. Of 15 arterial catheterisations, nine were performed in the operating room and six in the intensive care unit. Nine patients suffered ischaemic injury, which progressed to gangrene in three patients. Three patients developed haematoma that required surgical evacuation; two of these required vascular repair. One patient had compartment syndrome requiring fasciotomy and two patients had sheared catheter fragments that needed to be removed. All 15 patients had multiple comorbidities, and those in the operating room had an American Society of Anesthesiologists score of >or=3. Seven (46.6%) had arterial catheterisation done under emergent circumstances. Six (40%) died during hospitalisation because of complications unrelated to arterial catheterisation.

CONCLUSION

Arterial catheterisation had a very low rate of major complications. They seem associated with high severity of illness and emergency surgery.

Demography and clinical course of ulcerative colitis in a multiracial Asian population: a nationwide study from Malaysia

OBJECTIVE

To establish the clinical course of ulcerative colitis (UC) in the Malaysian population, comparing the three major ethnic groups: Malay, Chinese and Indian.

METHODS

Patients who were diagnosed with UC from seven major medical referral centers in Malaysia were recruited. Their baseline characteristics, and the extent of the disease, its clinical course and complications were recorded.

RESULTS

A total of 118 patients was included. The extent of disease was as follows: proctitis alone in 22 (18.6%), sigmoid colon in 23 (19.5%), descending colon in 16 (13.6%), transverse colon in 11 (9.3%), ascending colon and pancolitis 46 (39%). Most patients had chronic intermittent disease. Extra-intestinal complications were seen in 27 (22.9%) patients and fulminant colitis was seen in four (3.4%). None developed colorectal cancer. The overall cumulative colectomy rates at 1, 5 and 10 years were 3.4% (CI: 0.9-8.5), 5.9% (CI: 1.9-13.2) and 15.6% (CI: 6.5-29.4), respectively. There was a higher prevalence of extra-intestinal manifestations and a trend towards more extensive disease among Indian patients. However, no significant differences were seen in the age of onset, the severity of disease (fulminant colitis, refractory disease) and the colectomy rate.

CONCLUSION

As in developed countries, most of our patients have a remitting and relapsing pattern of disease but the clinical course appears to be milder, with lower rates of colectomies. There are differences in clinical presentation among the three major ethnic groups, with Indians having a higher prevalence of extra-intestinal manifestations and a trend towards more extensive disease.

Chemoprevention of colorectal cancer with nonsteroidal anti-inflammatory drugs

Colorectal carcinoma is one of the commonest solid organ tumors in the world and its prevalence appears to be increasing in Asia. Recently, there has been much interest in various chemotherapeutic agents for the management of this condition, in particular nonsteroidal anti-inflammatory drugs (NSAIDs). There is a large amount of data that suggest traditional NSAIDs, as well as the new cyclooxygenase (COX)-2 selective inhibitors such as rofecoxib and celecoxib, have a role in the setting of primary and secondary prevention, and adjuvant therapy of both sporadic colorectal carcinoma and familial adenomatous polyposis. This review examines some of this data, as well as the potential problems and limitations of using these agents, particularly in light of the recent withdrawal of rofecoxib.

Improved haemodynamic stability with administration of aprotinin during orthotopic liver transplantation

In a placebo-controlled, double-blind study, we have investigated the hypothesis that patients for orthotopic liver transplantation (OLT) treated with high-dose aprotinin (serum concentrations > or = 200 kiu ml-1) show greater haemodynamic stability on graft reperfusion. We studied 55 adult patients presenting for OLT, and 52 were included in the analysis. The treatment and placebo groups were similar in patient characteristics. The anaesthetic regimen used was standardized, and veno-venous bypass were used in all patients. Cardiac output measurements and haemodynamic profiles were recorded at intervals throughout anaesthesia and surgery. Arterial and mixed venous oxygen saturations were measured by co-oximetry. Derived variables were measured using standard formulae. Aprotinin treated patients had greater values for systemic vascular resistance on reperfusion, with a lesser cardiac index and calculated oxygen delivery. Oxygen consumption, however, was significantly greater, despite reduced delivery.

Effects of intraoperative N-acetylcysteine in orthotopic liver transplantation

N-acetylcysteine (NAC) is an antioxidant agent which has been shown to benefit patients with fulminant hepatic failure. We have examined its effect in patients with chronic liver disease undergoing orthotopic liver transplantation by giving NAC during operation. In a prospective, randomized, double-blind, placebo-controlled study of 50 patients, NAC appeared to induce mild vasodilatation, improve oxygen delivery and consumption, and reduce base deficit, but data interpretation was difficult. There were no significant effects on mortality, morbidity or postoperative graft function.

Orthotopic liver transplantation in patients over 60 years old

A retrospective examination was performed, including a case control study, of 40 patients aged 60 years and over who underwent liver transplantation at King's College Hospital, London, UK, between 1988 and September 1993. There was no significant difference between elderly patients and younger patients in preoperative condition, intraoperative interventions, or outcome assessed by survival, complication rate, and duration of stay on the intensive care unit. The only significant difference between age groups was the median length of hospital stay, which was 24 days for the elderly versus 20 days for younger patients. We conclude that age up to 70 years should not be a barrier to liver transplantation.