Glanzmann thrombasthenia in Pakistan: molecular analysis and identification of novel mutations

Glanzmann thrombasthenia (GT) is an inherited genetic disorder affecting platelets, which is characterized by spontaneous mucocutaneous bleeding and abnormally prolonged bleeding in response to injury or trauma. The underlying defect is failure of platelet aggregation due to qualitative and/or quantitative deficiency of platelet integrin αIIbβ3 resulting from molecular genetic defects in either ITGA2B or ITGB3. Here, we examine a Pakistani cohort of 15 patients with clinical symptoms of GT who underwent laboratory and molecular genetic analysis. In patients with a broad range of disease severity and age of presentation, we identified pathogenic mutations in ITGA2B in 11 patients from 8 different families, including 2 novel homozygous mutations and 1 novel heterozygous mutation. Mutations in ITGB3 were identified in 4 patients from 3 families, two of which were novel homozygous truncating mutations. A molecular genetic diagnosis was established in 11 families with GT, including 5 novel mutations extending the spectrum of mutations in this disease within a region of the world where little is known about the incidence of GT. Mutational analysis is a key component of a complete diagnosis of GT and allows appropriate management and screening of other family members to be performed.

Endometrial stromal sarcoma: a rare entity

Endometrial Stromal Sarcoma (ESS) is a hormone sensitive tumor. It is a rare gynecological tumor and is considered to occur more often in pre-menopausal women. A proper pre-operative diagnosis is difficult and confirmed in most cases after hysterectomy for a presumed benign disease. Endometrial sampling, ultrasound, and magnetic resonance imaging can provide diagnostic clues. For early disease complete surgical cure is possible, however, adjuvant therapy is available for recurrence. This case of Low Grade Endometrial Stromal Sarcoma (LGESS) in a 21 years old woman was presented as irregular vaginal bleeding. Clinical diagnosis of fibroid was made but analysis of endometrium showed ESS confirmed on hysterectomy specimen. One should consider it in any case with rapid fibroid enlargement.

Phenolic Glycosides from Symplocos racemosa

The re-investigation of the chemical constituents of the bark of the stem of Symplocos racemosa Roxb. led to the isolation of two new phenolic glycosides, Symconoside A (1) and Symconoside B (2). The structures of the new compounds were determined by 1D and 2D-homonuclear and heteronuclear NMR spectroscopy, chemical evidences, and by comparison with the published data of the closely related compounds. The phenolic glycosides 1 and 2 displayed in vitro inhibitory activity against phosphodiesterase-I with the IC50 values of 158±0.02 and 900±0.08 μM, respectively.

Comparison between transcerebellar diameter with biparietal diameter of ultrasound for gestational age measurement in third trimester of pregnancy

OBJECTIVE

To determine the frequency of correct assessment by transcerebeller diameter (TCD) versus biparietal diameter (BPD) for gestational age measurement at 36 weeks of pregnancy using first day of last menstrual period (LMP) for actual period of gestation.

STUDY DESIGN

Quasi experimental.

PLACE AND DURATION OF STUDY

Department of Obstetrics and Gynaecology, Bahawal Victoria Hospital, Bahawalpur from May to November 2010.

METHODOLOGY

This study was performed on 228 patients at 36 weeks of pregnancy fulfilling the inclusion criteria. Ultrasound measurements of TCD and BPD was made and compared with LMP. Collected data was analyzed by SPSS version 10. Proportoin of correct diagnosis by each measurement was determined and compared using chi-square test with significance at p < 0.05.

RESULTS

Out of 228 patients, TCD was found to give correct assessment in 209 patients (91.7%; p = 0.001) corresponding to the gestational age by LMP i.e 36 weeks. BPD was found to give correct assessment corresponding to the gestational age by LMP in 176 patients (77.2%).

CONCLUSION

Although both BPD and TCD are accurate biometric parameters at 36 weeks of gestation, transcerebellar diameter is more reliable method of gestational age determination in third trimester of pregnancy than biparietal diameter. TCD can be used as a tool to assist in the assessment of gestational age in third trimester.

Promoter DNA methylation regulates murine SUR1 (Abcc8) and SUR2 (Abcc9) expression in HL-1 cardiomyocytes

Two mammalian genes encode the SURx (SUR1, Abcc8 and SUR2, Abcc9) subunits that combine with Kir6.2 (Kcnj11) subunits to form the ATP-sensitive potassium (KATP) channel in cardiac myocytes. Different isoform combinations endow the channel with distinct physiological and pharmacological properties, and we have recently reported that the molecular composition of sarcolemmal KATP channels is chamber specific in the mouse heart. KATP channel composition is determined by what subunits are expressed in a cell or tissue. In the present study, we explore the role of CpG methylation in regulating SUR1 and SUR2 expression. In HL-1 cardiomyocytes, as in atrial myocytes, SUR1 expression is markedly greater than SUR2. Consistent with CpG methylation-dependent silencing of SUR2 expression, bisulfite sequencing of genomic DNA isolated from HL-1 cells demonstrates that 57.6% of the CpGs in the promoter region of the SUR2 gene are methylated, compared with 0.14% of the the CpG residues in the SUR1 sequence. Moreover, treatment with 10 µM 5-aza-2'-deoxycytidine (Aza-dC) significantly increased both the unmethylated fraction of the SUR2 CpG island and mRNA expression. However, we cannot rule out additional mechanisms of Aza-dC action, as Aza-dC also causes a decrease in SUR1 expression and lower doses of Aza-dC do not alter the unmethylated DNA fraction but do elicit a small increase in SUR2 expression. The conclusion that DNA methylation alone is not the only regulator of SUR subunit expression is also consistent with observations in native myocytes, where the CpG islands of both SUR genes are essentially unmethylated in both atrial and ventricular myocytes. Collectively, these data demonstrate the potential for CpG methylation to regulate SURx subunit expression and raises the possibility that regulated or aberrant CpG methylation might play a role in controlling channel structure and function under different physiological conditions or different species.

Colles' fracture - is it a signal of osteoporosis?

Asymptomatic post-menopausal osteoporosis is common but some-times associated with pain and deformity. Symptomatic osteoporosis is usually associated with fracture. A 59 years old post-menopausal woman presented with a history of acute low-back-pain. She had menopause for 12 years. She gave history of colles' fracture at about two years back. Her mother died as consequences of femoral neck fracture. MRI of vertebral spine showed demineralization with partial collapse of D6,7,12 and L1 vertebra. Dual energy X-ray absorptiometry of vertebra showed BMD T-score of -4.5. Patient was managed with IV infusion of zoledronic acid, oral intake of vitamin D and calcium supplements and with regular non-weight-bearing exercises. Her condition improved gradually. During post-menopausal period, every women must be aware of osteoporosis and any fracture in that time must be evaluated to rule out osteoporosis.

Impact of methods for uterine incision closure on repeat caesarean section scar of lower uterine segment

OBJECTIVE

To compare the effect of different suturing techniques in repeat caesarean section in terms of scar thickness, blood loss, operative time and scar dehiscence at the time of next caesarean section.

STUDY DESIGN

A randomized double blinded trial.

PLACE AND DURATION OF STUDY

Obstetrics and Gynaecology Department of Bahawal Victoria Hospital, Bahawalpur, from June 2005 to June 2010.

METHODOLOGY

Ninety patients undergoing repeat caesarean section were included and randomly assigned to one of the three groups. Group A underwent one layer closure; Group B underwent two layer closure while Group C underwent modified two layer closure of the uterine incision. Ultrasonographic evaluation of the scar thickness was performed at 6 weeks post operatively and longer follow-up was done in next caesarean for scar dehiscence. Frequency percentages were obtained and compared using chi-square test with significance at p < 0.05.

RESULTS

In only 2 (6.6%) of modified two layer closure cases, it was necessary to use additional haemostatic sutures, compared with 16 (53%) of one layer closure group, and 10 (33%) of the two layer closure group. At 6 weeks, the mean car thickness in group C (17.08 +1.635 mm) was significantly greater (p < 0.001) as compared to group A (13.19 + 1.32 mm) and group B (14.58 +1.18 mm). At long-term follow-up, only 1 (6%) case from group C showed the "uterine window" at the time of repeat caesarean section as compared to 3 (23%) in group A and 2 (14%) in group B.

CONCLUSION

Scar thickness was significantly increased with modified two layer closure when compared with traditional one and two layer closure of lower transverse uterine incision at the time of repeat caesarean section.

Misoprostol for the purpose of mid-trimester termination of pregnancy: a comparative study with prostaglandin F2 alpha

OBJECTIVE

To compare the efficacy of misoprostol verses prostaglandin F2alpha (PGF2alpha) in the medical management of termination of mid-trimester pregnancy due to medical reasons.

METHODS

This experimental study was conducted in Obstetrics and Gynaecology Department, Bahawal Victoria Hospital, Bahawalpur for a period of 6 months from April 2005 to September 2005. Time interval between induction with misoprostol or PGF2alpha and expulsion of foetus, number of tablets of misoprostol used and total dose of injection PGF2alpha used for termination of pregnancy as well as the complications experienced with both drugs. Fifty patients of 18-35 years of age were randomly selected who presented to Gynaecology and Obstetrics outdoor with mid-trimester foetal loss or congenitally malformed foetus incompatible to life, confirmed on ultrasonography. These women were randomised to receive either intravaginal misoprostol or extra-amniotic PGF2alpha.

RESULTS

Ninety-six percent of cases were managed successfully with Misoprostol as compared to 92% where PGF2alpha was tried (p > 0.5). Mean induction to expulsion duration for misoprostol and PGF2alpha were 9.02 +/- 4.57 and 16.04 +/- 6.22 hours respectively (p < 0.5). Complications profile was low especially in cases of PGF2alpha and only one case experienced significant haemorrhage.

CONCLUSION

Misoprostol and PGF2alpha were found to be of same success rate but former was found to be more efficacious in terms of induction to expulsion duration.

Pattern and management of renal injuries at Pakistan Institute of Medical Sciences

OBJECTIVE

To determine the types and grade of various renal injuries and methods adopted for their management at the Department of Urology, Pakistan Institute of Medical Sciences, Islamabad.

STUDY DESIGN

An observational study.

PLACE AND DURATION OF STUDY

Department of Urology, Pakistan Institute of Medical Sciences, Islamabad, from January 2005 to December 2007.

METHODOLOGY

The study included 50 patients with both blunt and penetrating renal trauma of either gender and aged above 13 years. Injuries, grade management and outcome was recorded. The data was entered in structured proforma and analyzed for descriptive statistics using SPSS version 10.

RESULTS

Frequency was higher in males (82%). The mode of renal injury was blunt in 78% and penetrating in 22% cases. Blunt injuries were mostly due to road traffic accident (94.9%) and penetrating injuries due to firearm (63.6%). Hematuria was present in 86% and absent in 14% cases. Minor renal injury was seen in 74% and major injury in 26% cases. Seventy-two percent of cases were managed conservatively. All grade-V (14%) and one grade-1V injury (2%) patients underwent nephrectomy. Renorrhaphy was done in 6% cases. Urinary extravasation was seen in one case (2%). One patient developed renocolic fistula. No mortality was observed in non-operative group; however, 4% patients expired in operative group due to associated injuries.

CONCLUSION

Blunt trauma accounts for majority of the cases of renal injury and non-operative treatment is the suitable method of management for most cases of blunt as well as selected cases of penetrating renal trauma, who are stable hemodynamically and without peritonitis.

Abstract 663: The comparative efficacy of the PARP inhibitors AG14361, ABT888 and AZD2281 in the treatment of triple negative and BRCA1 breast cancer

Introduction: Most preclinical studies have used “in vitro” animal cell lines, “in vivo” allografts and/or gene knockdowns to predict the clinical efficacy of PARP1 and PARP1 & 2 inhibitors in the treatment of human breast cancer. It has been shown however that “in vitro” experiments with human breast cancer cell lines are more useful in predicting the clinical performance of cancer drugs than these other methods. In this study, the PARP1 inhibitor AG14361 and the PARP1 & 2 inhibitors AZD2281 and ABT888 were tested against a panel of 25 human breast cancer cell lines. Methods: The MTT assay was used to determine the IC50 inhibitory effect of the PARP inhibitors against the human breast cancer cell lines over a 72 hour period with each experiment being replicated at least 10 times. The MTT assay was validated for each cell line using direct counting via hemacytometer & trypan blue staining. Human to mouse xenografts were then challenged by PARP inhibitors. The IC50 results were then correlated with the PARP activity of each cell line. Results: The PARP1 inhibitor AG14361 was 5 and 8 fold more effective in inhibiting human breast cancer growth than ABT888 and AZD2281 respectively. The average IC50 values for AG14361, ABT888 and AZD2281 against BRCA1-/- human breast cancer cell lines were 20, 120, and 190 micromolar respectively. The average IC50 values for non-BRCA1 triple negative breast cancer were 24, 110 and 165 micromolar respectively. ANOVA analysis sustained the null hypothesis between BRCA1-/- breast cancer and non-BRCA1 triple negative breast cancer. Xenograft studies mirrored the “in vitro results”. These IC50 values are significantly higher than previously published preclinical data that utilized BRCA1 -/- animal cell lines and human BRCA1 gene knockdowns. This suggests that BRCA1 animal cell lines are more sensitive to PARP1 inhibitors and that human BRCA1 -/- gene knockdowns may be fundamentally different from naturally derived BRCA1-/- breast cancer cell lines. Conclusion: The PARP1 inhibitor was more effective than the PARP1 & 2 inhibitors in inhibiting breast cancer growth. Non-BRCA1 triple negative breast cancers were at least as sensitive to PARP inhibition as BRCA1 breast cancers.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 663.

Abstract A42: The treatment of sporadic breast cancer with Poly(ADP-ribose) polymerase (PARP1) inhibitors (AZD2281, ABT888, AG14361) as single agents and in combination with chemotherapy

Introduction: It has been shown that poly(ADP-ribose) polymerase (PARP1) inhibitors may be useful in the treatment of BRCA1 and 2 hereditary breast cancers due to their deficiency in homologous repair. Many sporadic breast cancers may also be deficient in homologous repair due to deficiency's in RAD51, RAD54, DSS1, RPA1, NBS1, ATR, ATM, CH1, CHK2, FANCD2, FANCA, FANC or a down regulation of BRCA.

Methods: Human breast cancer cell lines representative of basal, Her2/neu, luminal A and luminal B subtypes were treated with PARP1 inhibitors alone or in combination with standard chemotherapeutic agents (alkylating, topoisomerase inhibitors, anti-metabolites, anti-mitotics and/or DNA intercalators) for 72 hours. IC50 values were determined by standard dose response curves of the PARP1) inhibitors (AZD2281, ABT888, AG14361), standard chemotherapeutic agents alone and in combination with each other. PARP1 inhibitor pharmacodynamic, PARP1 activity assays and the quantification of molecular markers from the apoptotic, DNA repair and mitotic pathways were also performed and correlated with IC50 values.

Results: There was no statistical difference in the IC50 of PARP1 inhibitors for BRCA1, non-BRCA1 triple negative or luminal human breast cancer tissue. Significant enhancement of chemotherapeutic cytotoxicity by PARP1 inhibitors was observed in not only hereditary (BRCA1 & BRCA2) breast cancer but, in sporadic breast cancer also. The results suggest that many sporadic breast cancers are deficient in homologous recombination and their ability to preserve DNA and chromosomal fidelity.

Conclusion: PARP1 inhibitors in combination with chemotherapy may be effective in treating sporadic breast cancer.

Citation Information: Clin Cancer Res 2010;16(7 Suppl):A42

Caveolin-1 promotes resistance to chemotherapy-induced apoptosis in Ewing's sarcoma cells by modulating PKCalpha phosphorylation

Caveolin-1 (CAV1) has been implicated in the regulation of several signaling pathways and in oncogenesis. Previously, we identified CAV1 as a key determinant of the oncogenic phenotype and tumorigenic activity of cells from tumors of the Ewing's Sarcoma Family (ESFT). However, the possible CAV1 involvement in the chemotherapy resistance commonly presented by an ESFT subset has not been established to date. This report shows that CAV1 expression determines the sensitivity of ESFT cells to clinically relevant chemotherapeutic agents. Analyses of endogenous CAV1 levels in several ESFT cells and ectopic CAV1 expression into ESFT cells expressing low endogenous CAV1 showed that the higher the CAV1 levels, the greater their resistance to drug treatment. Moreover, results from antisense- and shRNA-mediated gene expression knockdown and protein re-expression experiments demonstrated that CAV1 increases the resistance of ESFT cells to doxorubicin (Dox)- and cisplatin (Cp)-induced apoptosis by a mechanism involving the activating phosphorylation of PKCalpha. CAV1 knockdown in ESFT cells led to decreased phospho(Thr(638))-PKCalpha levels and a concomitant sensitization to apoptosis, which were reversed by CAV1 re-expression. These results were recapitulated by PKCalpha knockdown and re-expression in ESFT cells in which CAV1 was previously knocked down, thus demonstrating that phospho(Thr(638))-PKCalpha acts downstream of CAV1 to determine the sensitivity of ESFT cells to chemotherapeutic drugs. These data, along with the finding that CAV1 and phospho(Thr(638))-PKCalpha are co-expressed in approximately 45% of ESFT specimens tested, imply that targeting CAV1 and/or PKCalpha may allow the development of new molecular therapeutic strategies to improve the treatment outcome for patients with ESFT.

Protective effect of liposomal formulation of tuftsin (a naturally occurring tetrapeptide) against cyclophosphamide-induced genotoxicity and oxidative stress in mice

Tuftsin, a naturally occurring tetrapeptide with a sequence Thr-Lys-Pro-Arg was evaluated for its in vivo protective effect against cyclophosphamide-induced genotoxicity and oxidative stress in Swiss albino mice. The anticancer drug cyclophosphamide (CP) was administered intra-peritonially to induce mutagenic effect. The drug treatment caused significant increase in chromosomal aberrations, formation of micronucleated polychromatic erythrocytes (MNPCE's), as well as oxidative stress and decrease in lipid peroxidation in liver of the animals. The pretreatment with tuftsin abolished such effects in dose-dependent manner and also increased mitotic index in the experimental animals. Results of the present study validated chemo-preventive properties of tuftsin against CP-induced chromosomal mutations and cellular injury of liver by oxidative stress.

Label-free global serum proteomic profiling reveals novel celecoxib-modulated proteins in familial adenomatous polyposis patients

Celecoxib, a selective inhibitor of cyclooxygenase-2 (Cox-2), was efficacious in clinical prevention trials of patients with familial adenomatous polyposis (FAP) and sporadic colorectal cancer. To identify as yet poorly defined molecular determinants of celecoxib efficacy, a multidimensional serum fractionation approach was used coupled with nanospray tandem mass spectrometry to perform label-free global proteomic profiling of serum samples from the FAP/celecoxib prevention trial. Subsequently, the application of an algorithm for large-scale biomarker discovery on comparative serum proteomic profiles of pre- and post-celecoxib treatment samples identified 83 potentially celecoxib-responsive proteins from various cellular compartments, biological processes and molecular functions. Celecoxib modulation of some of these proteins was confirmed in serum samples of FAP patients and colorectal cancer cell lines by Western blotting. Thus, using a shotgun procedure to rapidly identify important celecoxib-modulated proteins, this pilot study has uncovered novel systemic changes some of which are highly relevant for carcinogenesis and vascular biology. Validation of selected markers, especially those involved in key signaling networks and those considered molecular indicators of cardiovascular pathology, in larger celecoxib clinical trials is expected to provide insights into the molecular mechanisms of celecoxib and the efficacy/toxicity issues related to its use as a chemopreventive agent.

Comparison of the antidiabetic activity of Berberis lyceum root extract and berberine in alloxan-induced diabetic rats

Berberine has been shown to have hypoglycaemic activity in several in vitro and in vivo models, although the mechanism of action is not fully known. Berberis lyceum Royle root produces high concentrations of berberine, and in traditional medicine, the whole extract of this plant is used widely to treat diabetes. The antidiabetic activity of the ethanol root extract of Berberis lyceum was compared with pure berberine in normal and alloxan-diabetic rats using similar doses of each. The concentration of berberine in the extract was determined to be 80% dry weight with only trace amounts of other alkaloids present. The purpose of the study was to investigate the effects of berberine and a whole extract of Berberis lyceum on blood glucose and other parameters associated with diabetes, to compare the effects of the crude extract with those of pure berberine and thus validate its use as a therapeutic agent, and finally to identify any contribution of the other components of the extract to these effects. Oral administration of 50 mg/kg of Berberis extract and berberine to normal and experimental diabetic rats produced a significant (p < 0.05) reduction in blood glucose levels from days 3-7 days of treatment. Significant effects were also observed on the glucose tolerance, glycosylated haemoglobin, serum lipid profiles and body weight of experimental animals. Berberis extract and berberine demonstrated similar effects on all parameters measured, and although the extract was comparable in efficacy to berberine, it did not produce any effects additional to those shown by pure berberine. The results support the use of the extract in traditional medicine, and demonstrate that apart from being a highly cost-effective means of treating with berberine, the total extract does not appear to confer any additional benefits or disadvantages compared with the pure compound.

Altered gene expression profiles define pathways in colorectal cancer cell lines affected by celecoxib

It is well established that celecoxib, a selective inhibitor of cyclooxygenase-2 (COX-2) and a tested chemopreventive agent, has several COX-2-independent activities. In an attempt to better understand COX-2-independent molecular mechanisms underlying the chemopreventive activity of celecoxib, we did global transcription profiling of celecoxib-treated COX-2-positive and COX-2-deficient colorectal cancer cell lines. Celecoxib treatment resulted in significantly altered expression levels of over 1,000 to 3,000 transcripts in these cell lines, respectively. A pathway/functional analysis of celecoxib-affected transcripts, using Gene Ontology and Biocarta Pathways and exploring biological association networks, revealed that celecoxib modulates expression of numerous genes involved in a variety of cellular processes, including metabolism, cell proliferation, apoptotic signaling, cell cycle check points, lymphocyte activation, and signaling pathways. Among these processes, cell proliferation and apoptotic signaling consistently ranked as the highest-scoring Gene Ontology terms and Biocarta Pathways in both COX-2 expresser and nonexpresser cell lines. Altered expression of many of the genes by celecoxib was confirmed by quantitative PCR and at the protein level by Western blotting. Many novel genes emerged from our analysis of global transcription patterns that were not previously reported to be affected by celecoxib. In the future, in-depth work on selected genes will determine if these genes may serve as potential molecular targets for more effective chemopreventive strategies.

Comparison of CT scan and colour flow Doppler ultrasound in detecting venous tumour thrombous in renal cell carcinoma

BACKGROUND

Renal cell carcinoma has marked tendency to spread into renal vein, inferior vena cava and right side of heart. Extension of tumour thrombus into these veins will alter the surgical approach. We have compared the CT scan with Colour flow Doppler ultrasound in detecting venous tumour thrombus in renal vein and inferior vena cava.

METHODS

This cross-sectional study included 30 adult patients presenting with renal tumour. Patients of either gender were included in the study. Non probability convenience sampling was used. All patients underwent colour flow Doppler ultrasound and CT scan with contrast to asses the renal vein and inferior vena cava. The results were confirmed by intra operative findings and histopathology. The data was analyzed using SPSS version 12.

RESULTS

Out of 30 patients, 20 (66%) were males and 10 (34%) female. The tumour was predominantly on the right side (60%), as was renal venous tumour thrombus (44%). Inferior vena cava was involved in 4 cases predominantly due to right sided tumours. The sensitivity of Doppler ultrasound in detecting renal venous tumour thrombus (88% on right and 100% on left side) was higher than CT scan (63% on right and 60% on left side). Doppler ultrasound was also superior to CT scan in detecting vena caval thrombus.

CONCLUSION

The overall sensitivity of Doppler sonography was higher than CT scan in detecting tumour extension into renal veins and inferior vena cava. Therefore, it can be used as a complementary tool in equivocal cases.