Role of Galectin-3 in the activation of p-ERK and in resistance to radiotherapy in glioblastoma through the activation of p-ERK independent of Ras activity

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Background: There has been a growing interest in investigating the molecular mechanisms leading to treatment resistance in glioblastoma (GBM). The MAPK pathway has been shown to be involved in mediating treatment resistance. Galectin-3 (Gal3) is commonly overexpressed in astrocytic tumors of the brain and has been associated with adverse clinical outcomes. We investigated the role and mechanisms of Gal3 in mediating treatment resistance in GBM through modulating the MAPK pathway. Methods: We investigated Gal3 expression in GBM cell lines (U87, LN18, LN229). We created stable Gal3 knockdown cell lines (Gal3KD), ERK-knockdown (lentiviral shRNA) and constitutively active MEK(MEK2DD plasmid obtained from Dr. Brugge) cell lines. We then evaluated the radiosensitivity, apoptosis, and cell viability of control cell lines treated by non-targeting (NT) vectors as compared to Gal3KD, ERKKD and MEK2DD using clonogenic survival, Annexin V/PI apoptosis, COMET, and cell cycle assays. Signaling cascades were evaluated using Western blot and a GTP-ras pull down assay. Gal3 was also transiently knocked down in MEK2DD and NT cell lines and signaling cascades were analyzed using western blotting. Gal3 binding interactions were identified using co-immunoprecipitation. Results: Gal3 expression was induced in all GBM cell lines following irradiation. Gal3KD showed increased radiosensitivity similar to ERKKD as compared to controls with decreased clonogenic survival, increased DNA damage, increased apoptosis, and increased cell cycle arrest in G1 and G2, while MEK2DD showed enhanced radioresistance. Gal3KD showed reduced p-ERK at baseline followed by a minimal induction of p-ERK with irradiation as compared to controls which have a high level of p-ERK. Overall p-Akt, ERK and Ras-GTP levels were equivalent in Gal3KD and controls. When Gal3 was transiently knocked down in MEK2DD cell line, p-ERK was drastically reduced similar to controls. Gal3 co-immunoprecipitated with ERK. Conclusions: Our results suggest a possible direct novel interaction between Gal3 and ERK in GBMs that is essential for the expression of p-ERK and mediating treatment resistance in GBMs.

No significant financial relationships to disclose.

Cytomegalovirus infection: an Indian perspective

Human cytomegalovirus (CMV) poses an important public health problem as it may cause serious morbidity and mortality in congenitally infected newborns and immunocompromised patients, most notably transplant recipients and HIV-infected persons. It is probably one of the most common infections known to humans and is characterized by a self-limiting infection in healthy individuals. CMV infection is the single most frequent cause of infectious complications in the early period following kidney transplantation Post-transfusion cytomegalovirus infection is of concern in the immunocompetent as well as in certain categories of immunocompromised individuals such as neonates, pregnant women, recipients of bone marrow and other organ transplants and individuals with immunodeficiency disorders. The emergence of AIDS in India has necessitated the establishment of reliable tests for diagnosis of cytomegalovirus infection as a damaged immune system permits cytomegalovirus reactivation. The magnitude of this problem in India and the various diagnostic modalities used have not been adequately investigated and, hence, CMV infection is still a major health problem warranting strong preventive measures. The ultimate goal of the prevention program is to develop a vaccine that can be administered to seronegative women of childbearing age to prevent primary infection during pregnancy.

Lipoma of the deep lobe of parotid gland - a case report and review of literature

Lipoma of deep lobe of parotid gland is a rare clinical entity. Less than 10 cases have been reported in the literature in our knowledge. Because of their rarity, they are not often considered in the differential diagnosis of parotid tumors. A case of 45-year-old man with an unusually large deep lobe lipoma of parotid gland is presented in this article which was surgically managed by total conservative parotidectmy. The clinical picture, radiological and histopathological features of this entity is being discussed here. Review of literature of this clinical situation has been presented in the present article.

Statistical analysis of radiation hybrid data

This unit opens with a comparison of radiation hybrid and somatic cell hybrid analyses. Definitions, assumptions, and a mathematical model for radiation hybrid analysis are presented. In addition, parametric and nonparametric methods of data analysis are presented.

Primary tuberculosis of tonsil and posterior oropharyngeal wall

Pharyngeal tuberculosis is rare and usually occurs in association with primary pulmonary disease. Primary tuberculosis involving the palatine tonsils and the posterior oropharyngeal wall is still a rare clinical entity. We report one such case of primary tuberculosis involving both the palatine tonsils and the posterior oropharyngeal wall in a 22 year-old male. The patient responded to anti-tubercular treatment with complete disappearance of lesion and no sign of recurrence on one year follow-up. The final diagnosis was based upon histopathological report.

Hirschsprung disease, associated syndromes and genetics: a review

Hirschsprung disease (HSCR, aganglionic megacolon) represents the main genetic cause of functional intestinal obstruction with an incidence of 1/5000 live births. This developmental disorder is a neurocristopathy and is characterised by the absence of the enteric ganglia along a variable length of the intestine. In the last decades, the development of surgical approaches has importantly decreased mortality and morbidity which allowed the emergence of familial cases. Isolated HSCR appears to be a non-Mendelian malformation with low, sex-dependent penetrance, and variable expression according to the length of the aganglionic segment. While all Mendelian modes of inheritance have been described in syndromic HSCR, isolated HSCR stands as a model for genetic disorders with complex patterns of inheritance. The tyrosine kinase receptor RET is the major gene with both rare coding sequence mutations and/or a frequent variant located in an enhancer element predisposing to the disease. Hitherto, 10 genes and five loci have been found to be involved in HSCR development.

The Fate of 12 Recessive Mutations in A Single Village

In a Muslim Arab village, relatively isolated because of the preference of consanguineous marriages, we studied the fate of 12 mutations in 5 different genes. The study was based on carriers detected among relatives of affected patients and of carriers discovered in a random sample of 424 adults. Most of the mutations have been introduced by a carrier(s) originating from another village, but a few have been de novo events. Mutations that are very frequent in the entire village were introduced soon after the foundation of the village. Examples of such mutations are [GBJ2, 35Gdel] and [MEFV, M680I], with a carrier frequency of 7.8% and 6.2%, respectively. Many of the other mutations that are rare were introduced recently into the village and are frequent only among the descendants of the first couple carrying the mutation. For instance all the carriers of [ARSA, Q190H], responsible for metachromatic leukodystrophy, were found among the 218 descendants of a couple who were living in the village 4 generations ago. Since the village is typical for the region this study allows for some general conclusions to be drawn. In a population with a high degree of inbreeding the diagnosis of a single family with a patient(s) affected with a recessive disorder points to a recent event, while the finding of a rare disease in several families from an inbred population points to an older mutation. Mutations are often "exported" from one population to another by marriage. In the new inbred population this novel mutation will either be lost or will become frequent as the result of a founder effect. These observations are important for genetic counselling in the case of a recent mutation, since only the descendants of the founder couple are at risk, while in the case of older mutations the risk may be for the entire village. In the case of those frequent ancient mutations, the risk for a relative of an affected individual will be similar whether he marries a close relative or any random individual in the village.

Distribution of hepatitis C virus genotypes in beta-thalassaemic patients from Northern India

Multitransfused beta-thalassaemic patients constitute a population having a higher prevalence of hepatitis C virus (HCV) infection because of its transmission from infected blood collected during seronegative window period. HCV genotyping in thalassaemic patients is mainly useful for the clinical management of the patients and for facilitating decisions on therapy. Thus, the aim of the present study was to identify the genotypes that are prevalent in thalassaemic patients and to correlate these with gender, age, number of blood transfusions and the liver function test profiles. Reverse transcription-polymerase chain reaction (RT-PCR) was carried out in 80 beta-thalassaemic patients (58 men and 22 women) for detection of HCV RNA who were seronegative for hepatitis B virus or human immunodeficiency virus antibodies. HCV genotyping was carried out by restriction fragment length polymorphism (RFLP) method of Chinchai et al. Type-specific PCR followed by direct sequencing was also used to confirm the mixed-genotype infection. Among the 80 thalassaemic patients, 20 and eight patients were infected with genotypes 3 and 1, respectively, whereas two cases had infection with HCV genotype1c/5a. The serum levels of aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase were found to be significantly altered between the two groups of HCV-infected and noninfected thalassaemic patients. No significant correlation was observed between genotypes when compared with gender, age and number of blood transfusions, except significantly higher level of ALP in genotype 1 than in genotype 3. Genotype 3 alone was the predominant type in beta-thalassaemic patients, with approximately 45% being infected with mixed type. Hence, detection of HCV RNA would help in decreasing the transmission of HCV-infected blood collected during the seronegative window period, whereas determination of genotypes would provide help in adoption of different treatment policies for better management of thalassaemic patients.

An update of phase II results from RTOG 0211: A phase I/II study of gefitinib with radiotherapy in newly diagnosed glioblastoma

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Background: The epidermal growth factor receptor (EGFR) pathway is commonly deregulated in GBMs and its activity has been associated with treatment resistance in preclinical models. Accordingly, the Radiation Therapy Oncology Group (RTOG) recently conducted a Phase I/II study of Gefitinib, an EGFR tyrosine kinase inhibitor, in combination with radiotherapy for newly-diagnosed glioblastoma (GBM) patients. Methods: 178 GBM patients were entered on RTOG 0211 (Phase I: 31 patients and Phase II: 147 patients). The maximum tolerated dose (MTD) of Gefitinib was determined to be 500mg in non-EIACD patients, and the Phase II component of RTOG 0211 was continued at this dose level during radiation and as maintenance for 18 months afterward or until disease progression. Results: 119/147 patients completed treatment per protocol and/or with acceptable deviation. The median survival time for all patients in the study was 11.0 months. Progression-free survival was 5.1 months for all patients. When considering only patients who were treated per protocol, the median survival of RTOG 0211 patients was 11.5 months, compared to 11.0 months for historical controls treated in previous RTOG studies (p=0.14). RPA Class IV patients appeared to derive the greatest benefit from Gefitinib when combined with radiotherapy compared to historical controls, although not reaching statistical significance. Molecular and genetic profiling efforts are underway to determine which GBM patients derive greatest benefit from Gefitinib in the upfront setting, which will be reported at the time of the annual meeting. These include markers such as EGFRvIII and PTEN, which have been recently reported to be associated with response to anti-EGFR agents in the recurrent setting, and members of key signal transduction pathways regulated by EGFR. Conclusions: The observed survival advantage of newly-diagnosed GBM patients treated with Gefitinib in combination with radiotherapy compared to historical controls treated on previous RTOG studies does not reach statistical significance. Molecular and genetic profiling efforts are underway to identify subsets of GBM patients who might derive the greatest benefit from Gefitinib in the upfront setting.

No significant financial relationships to disclose.

Prospective neurocognitive effects and quality of life (QOL) in patients with multiple brain metastases receiving whole brain radiation (WBRT) ± thalidomide on radiation therapy oncology group (RTOG) trial 0118

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Background: RTOG 0118 was a randomized trial of WBRT (37.5 Gy/15 fractions) ± thalidomide in patients (pts) with brain metastases, which showed no effect on survival (Knisely et al, ASCO, 2005). This analysis examined the relationship between neurocognitive progression (NCP) and QOL in patients on both arms. Methods: NCP was assessed with the Folstein Mini-Mental Status Exam (MMSE) and QOL with the Spitzer QOL Index (SQLI). Pts with MMSE scores below age/education adjusted cutoff levels were considered to have NCP. T-test and Chi-Square statistics were used to determine significant differences in NCP and QOL between the two treatment arms over time. Results: Of 176 pts, 88 and 92% had SQLI and MMSE scores at baseline (43% were below the MMSE cutoff). Baseline SQLI (but not MMSE) was a significant predictor for OS (p=0.034). From baseline, SQLI and MMSE compliance rates were 74 and 60% at 1–2 months (mo), 37 and 29% at 4 mo, and 21 and 19% at 6 months, respectively. While QOL was stable, those who failed to meet MMSE cutoffs increased by 60% by 6 mo, on both study arms. Although a weak correlation (r=.23) existed at baseline between QOL and MMSE for both the WBRT (0.04) and WBRT/thalidomide (0.058) arms, there was no correlation beyond baseline. Conclusions: Baseline QOL is a significant predictor of OS. While QOL remained essentially stable, the degree of neurocognitive decline (60%) over time is concerning. These findings suggest the importance of these outcome measures in pts with brain metastases and the need for interventions to conserve cognitive status. RTOG is developing a trial to study the role of preventive strategies for NCP in brain metastases.

No significant financial relationships to disclose.

A study on the perinatal transmission of the hepatitis B virus

The purpose of this study was to determine the age wise prevalence of Hepatitis B virus (HBV) in children under five years and to analyze the relative importance of horizontal or vertical transmission. This study included 400 children in the age group of less than five years attending the outpatient department of pediatrics with minor complaints. History of HBV immunization was taken as the exclusion criteria. All the samples were tested for Hepatitis B surface antigen (HBsAg) and anti HBs using commercial ELISA kits. Liver function tests were performed on all the HBsAg positive patients. Hepatits B nucleocapsid antigen (HBeAg) was detected in few HBsAg positive mothers. Overall HBsAg positivity in children below five years was 2.25%. There was no statistically significant difference in HBsAg positivity in the different age groups by chi square test. HBsAg positivity in mothers was 4.25%. However only in three cases the pair of mother and child were both positive for HBsAg. The mean anti HBs positivity in children was 23.75%. There was no statistically significant difference in the anti HBs positivity in different age groups of children. The observation that there is no statistically significant difference in the prevalence of HBV infection (HBsAg and HBs) amongst different age groups of children below five years signifies that a large proportion of HBV infection in children of this age is acquired via vertical transmission. It is also indicated that this mode of disease transmission is responsible for the majority of chronic carriers. Universal immunization of all infants is desirable to decrease the carrier pool and it is inferred from the present study that Hepatitis B immunization should begin at birth to have greater impact.

Removal of catheter at midnight versus early morning: the patients' perspective

BACKGROUND

With an increasing role of the patient as a partner in making a combined decision in care plan goals, it is important to identify the patient's perspective of the experience of removal of catheter (ROC).

METHODS

A non-consecutive prospective randomized study was performed in 84 patients who underwent a transurethral resection of the prostate to determine the impact of midnight versus early-morning ROC on sleep deprivation, over all discomfort to the patient.

RESULTS

There was no difference in the patient experience in both groups. We found a reduced frequency during the first 6 h of ROC at midnight. However, there was an increased incidence of sleep disturbances in this group. This may in part be due to an anxiety of urge incontinence and may be allayed by appropriate counselling. There was no delay in discharge of the patients in both groups.

CONCLUSION

The patients must, therefore, be given the choice of ROC either at midnight or early morning, as the advantages of a reduced frequency must be correlated with an increased incidence of sleep disturbances.