Region of interest (ROI) selection using vision transformer for automatic analysis using whole slide images

Selecting regions of interest (ROI) is a common step in medical image analysis across all imaging modalities. An ROI is a subset of an image appropriate for the intended analysis and identified manually by experts. In modern pathology, the analysis involves processing multidimensional and high resolution whole slide image (WSI) tiles automatically with an overwhelming quantity of structural and functional information. Despite recent improvements in computing capacity, analyzing such a plethora of data is challenging but vital to accurate analysis. Automatic ROI detection can significantly reduce the number of pixels to be processed, speed the analysis, improve accuracy and reduce dependency on pathologists. In this paper, we present an ROI detection method for WSI and demonstrated it for human epidermal growth factor receptor 2 (HER2) grading for breast cancer patients. Existing HER2 grading relies on manual ROI selection, which is tedious, time-consuming and suffers from inter-observer and intra-observer variability. This study found that the HER2 grade changes with ROI selection. We proposed an ROI detection method using Vision Transformer and investigated the role of image magnification for ROI detection. This method yielded an accuracy of 99% using 20 × WSI and 97% using 10 × WSI for the ROI detection. In the demonstration, the proposed method increased the diagnostic agreement to 99.3% with the clinical scores and reduced the time to 15 seconds for automated HER2 grading.

Expert survey on management of prostate cancer in India: Real-world insights into practice patterns

To gain insights on the diverse practice patterns and treatment pathways for prostate cancer (PC) in India, the Urological Cancer Foundation convened the first Indian survey to discuss all aspects of PC, with the objective of guiding clinicians on optimizing management in PC. A modified Delphi method was used, wherein a multidisciplinary panel of oncologists treating PC across India developed a questionnaire related to screening, diagnosis and management of early, locally advanced and metastatic PC and participated in a web-based survey (WBS) (n = 62). An expert committee meeting (CM) (n = 48, subset from WBS) reviewed the ambiguous questions for better comprehension and reanalyzed the evidence to establish a revote for specific questions. The threshold for strong agreement and agreement was ≥90% and ≥75% agreement, respectively. Sixty-two questions were answered in the WBS; in the CM 31 questions were revoted and 4 questions were added. The panelists selected answers based on their best opinion and closest to their practice strategy, not considering financial constraints and access challenges. Of the 66 questions, strong agreement was reached for 17 questions and agreement was achieved for 22 questions. There were heterogeneous responses for 27 questions indicative of variegated management approaches. This is one of the first Indian survey, documenting the diverse clinical practice patterns in the management of PC in India. It aims to provide guidance in the face of technological advances, resource constraints and sparse high-level evidence.

Prevalence of BRCA1 and BRCA2 Mutations Among Patients With Ovarian, Primary Peritoneal, and Fallopian Tube Cancer in India: A Multicenter Cross-Sectional Study

PURPOSE

There are deficient data on prevalence of germline mutations in breast cancer susceptibility genes 1 and 2 (BRCA1/BRCA2) in Indian patients with ovarian cancer who are not selected by clinical features.

METHODS

This prospective, cross-sectional, noninterventional study in nine Indian centers included patients with newly diagnosed or relapsed epithelial ovarian, primary peritoneal, or fallopian tube cancer. The primary objective was to assess the prevalence of BRCA1/BRCA2 mutations, and the secondary objective was to correlate BRCA1/BRCA2 status with clinicopathologic characteristics. Mutation testing was performed by a standard next-generation sequencing assay.

RESULTS

Between March 2018 and December 2018, 239 patients with a median age of 53.0 (range, 23.0-86.0 years) years were included, of whom 203 (84.9%) had newly diagnosed disease, 36 (15.1%) had family history of ovarian or breast cancer, and 159 (66.5%) had serous subtype of epithelial ovarian cancer. Germline pathogenic or likely pathogenic mutations in BRCA1 and BRCA2 were detected in 37 (15.5%; 95% CI, 11.1 to 20.7) and 14 (5.9%; 95% CI, 3.2 to 9.6) patients, respectively, whereas variants of uncertain significance in these genes were seen in four (1.7%; 95% CI, 0.5 to 4.2) and six (2.5%; 95% CI, 0.9 to 5.4) patients, respectively. The prevalence of pathogenic or likely pathogenic BRCA mutations in patients with serous versus nonserous tumors, with versus without relevant family history, and ≤ 50 years versus > 50 years, were 40 of 159 (25.2%; 95% CI, 18.6 to 32.6) versus 11 of 80 (13.8%; 95% CI, 7.1 to 23.3; P = .0636), 20 of 36 (55.6%; 95% CI, 38.1 to 72.1) versus 41 of 203 (20.2%; 95% CI, 14.9 to 26.4; P < .0001), and 20 of 90 (22.2%; 95% CI, 14.1 to 32.2) versus 31 of 149 (20.8%; 95% CI, 14.6 to 28.2; P = .7956), respectively.

CONCLUSION

There is a high prevalence of pathogenic or likely pathogenic germline BRCA mutations in Indian patients with ovarian cancer.

A systematic review of dermatologic manifestations among adult patients with COVID-19 diagnosis

BACKGROUND

Infection with COVID-19 is characterized by respiratory, gastrointestinal and neurologic symptoms. However, limited evidence exists of the involvement of the integumentary system among COVID-19 patients and evidence suggests that these symptoms may even be the first presenting sign.

OBJECTIVE

To systematically evaluate the literature published on dermatologic signs of COVID-19 in order to educate doctors about the dermatologic signs of COVID-19 infection.

METHODS

Lit COVID, World Health Organization COVID-19 database and PubMed were searched using terminology to identify adult patients with confirmed COVID-19 infection and dermatologic manifestations of disease. The last search was completed on 13 July 2020.

RESULTS

There were 802 reports found. After exclusion, 20 articles were found with 347 patients with confirmed COVID-19 infection. Within these articles, 27 different skin signs were reported.

LIMITATIONS

Limitations of this review include the recency of COVID-19 infection; so, there are limited published reports and that many reports are not by dermatologists, and so, the cutaneous signs may be misdiagnosed or misdescribed.

CONCLUSION

Dermatologic manifestations of COVID-19 may be the first presenting sign of infection; so, dermatologists and doctors examining the skin should be aware of the virus's influence on the integumentary system in order to promptly diagnose and treat the infected patients.

Modelling the Anatomic Distribution of Neurologic Events in Patients with COVID-19: A Systematic Review of MRI Findings

BACKGROUND

Neurologic events have been reported in patients with coronavirus disease 2019 (COVID-19). However, a model-based evaluation of the spatial distribution of these events is lacking.

PURPOSE

Our aim was to quantitatively evaluate whether a network diffusion model can explain the spread of small neurologic events.

DATA SOURCES

The MEDLINE, EMBASE, Scopus, and LitCovid data bases were searched from January 1, 2020, to July 19, 2020.

STUDY SELECTION

Thirty-five case series and case studies reported 317 small neurologic events in 123 unique patients with COVID-19.

DATA ANALYSIS

Neurologic events were localized to gray or white matter regions of the Illinois Institute of Technology (gray-matter and white matter) Human Brain Atlas using radiologic images and descriptions. The total proportion of events was calculated for each region. A network diffusion model was implemented, and any brain regions showing a significant association (P < .05, family-wise error-corrected) between predicted and measured events were considered epicenters.

DATA SYNTHESIS

Within gray matter, neurologic events were widely distributed, with the largest number of events (∼10%) observed in the bilateral superior temporal, precentral, and lateral occipital cortices, respectively. Network diffusion modeling showed a significant association between predicted and measured gray matter events when the spread of pathology was seeded from the bilateral cerebellum (r = 0.51, P < .001, corrected) and putamen (r = 0.4, P = .02, corrected). In white matter, most events (∼26%) were observed within the bilateral corticospinal tracts.

LIMITATIONS

The risk of bias was not considered because all studies were either case series or case studies.

CONCLUSIONS

Transconnectome diffusion of pathology via the structural network of the brain may contribute to the spread of neurologic events in patients with COVID-19.

A Randomized, Multiple-Dose, Multicenter, Comparative Parallel Study to Evaluate the Safety and Efficacy of Intravenous Infusion of Rituximab (Hetero) and Reference Medicinal Product (Rituximab, Roche) in Indian Patients of Non-Hodgkin's Lymphoma (HERILY)

Objective: To compare the antitumor efficacy, safety, and pharmacodynamic (PD) characteristics of Hetero-rituximab (test) with reference medicinal product (rituximab, Roche) in non-Hodgkin's lymphoma. Patients and Methods: One hundred and thirty-five patients with diffuse large B-cell lymphoma (DLBCL) were randomized to receive intravenous infusion of either test or reference product. Efficacy (best overall response [BOR] rate [primary end point]), safety, PD (CD19), and immunological assessments (secondary end points) were done at the end of cycle 3 and cycle 6. Results:: At the end of 6 cycles, BOR rate was 73.47% in Hetero-rituximab test arm compared to the 69.09% in reference arm. Anti-rituximab antibodies were found to be negative at cycle 3 and cycle 6 for all patients. Patients treated with Hetero-rituximab show a significant depletion in CD19+ cell which was comparable with reference drug. Safety and immunogenic potential of the test drug was comparable to the reference drug in the patients of DLBCL. Conclusion: BOR rate at cycle 3, cycle 6, and end of the study lies within the prespecified limit for noninferiority which concludes that test product is therapeutically noninferior to reference medicinal product.

A Prospective, Randomized, Multiple-Dose, Multi-Center, Comparative Clinical Study to Evaluate the Efficacy, Safety, Immunogenicity of a biosimilar Bevacizumab (Test product, Hetero) and Reference Medicinal Product (Bevacizumab, Roche) in Patients of Metastatic Colorectal Cancer

OBJECTIVE

:To compare efficacy and safety of a biosimilar, Bevacizumab (Hetero) vs reference medicinal product (Bevacizumab, Roche) as first line therapy in patients with metastatic colorectal cancer (mCRC) in combination with chemotherapy.

METHODS

Patients of aged 18 to 65 with histologically pre-confirmed mCRC and treatment naïve with unresectable metastatic disease or distant metastases were enrolled and randomized to receive either Hetero-Bevacizumab or RMPBevacizumab along with chemotherapy (XELOX or FOLFOX-4) regimen over a period of 24 weeks (up to 8 cycles of Hetero-Bevacizumab/RMP-Bevacizumab+ XELOX regimen (each cycle of 3 weeks) or up to 12 cycles of Hetero-Bevacizumab/ RMP-Bevacizumab + FOLFOX-4 regimen (each cycle of 2 weeks). Bevacizumab was administered at 7.5 mg/kg as an IV infusion over 60-90 minutes on Day 1 of each treatment cycle. The efficacy endpoints were the overall response rate (CR+PR) and disease control rate (DCR) according to RECIST 1.1. The safety endpoints included assessments of treatment emergent adverse events and immunogenicity.

RESULTS

160 patients were screened; 111 patients were randomized in the study. No statistical significant difference in overall response rate between both the treatment groups (HB-MAB vs. RB-MAB: 35.56 % vs. 20%, P=0.28 at Week 6; 37.50 % vs. 30.77 %, P=0.73 at Week 12). Similar trend was observed for disease control rate (HB-MAB vs. RB-MAB: 100% vs. 96%, P=0.36 at Week 6; 95.83 vs. 100%, P=1.00 at Week 12).

CONCLUSIONS

Herero's Bevacizumab was found to be comparable to reference medical product, Bevacizumab in terms of efficacy and tolerability for the Indian patients with metastatic colorectal cancer.

Sensitization of Chronic Myeloid Leukemia Cells to Adriamycin Cytotoxicity by Clofibrate

Clofibrate (CPIB), an antihyperlipidemic agent, was employed as a drug response modulator in this study to evaluate its action, if any, on adriamycin (ADR) cytotoxicity in adriamycin insensitive chronic myeloid leukemia (CML) cells in vitro. Inhibition of (3H)-thymidine incorporation was used as a measure of DNA biosynthesis inhibition. A marginally toxic concentration of CPIB [0.001 % (v/v)] was utilized to evaluate the cytotoxicity in CML cells exposed to ADR 5 and 10 μg/ml. A heterogeneous response was observed in 16 different CML blood samples, 9 samples displaying a synergistic, 3 an additive and 4 a less than additive inhibition of DNA biosynthesis when exposed to the combination of ADR and CPIB. The cytotoxic effect induced by ADR alone and in combination with CPIB was found to be irreversible. The data suggest that the cell membrane modulating drug CPIB is effective as an adjuvant to enhance the antiproliferative action of ADR.

Double trouble: Co-occurrence of testosterone deficiency and body fatness associated with all-cause mortality in US men

BACKGROUND

Testosterone deficiency (TD, total testosterone ≤350 ng/dL [12.15 nmol L^-1 ]) and obesity epidemic are growing in parallel in the United States. Yet, the sequelae of TD and obesity on the risk of mortality remain unclear.

OBJECTIVE

To investigate whether the co-occurrence of TD and overall obesity (body mass index ≥30 kg/m² ), and abdominal obesity (waist circumference ≥102 cm), is associated with a risk of all-cause mortality in American men.

DESIGN

The data were obtained from the NHANES 1999-2004 and the Linked Mortality File (December 31, 2011). A total of 948 participants aged ≥20 years old with endogenous sex hormones and adiposity measurements data were included in this study.

RESULTS

Over a median of 9.5 years of follow-up, 142 men died of any cause in this cohort. Multivariable analysis showed a 2.60 fold increased risk of death among men with TD compared with men without TD (Hazard Ratio [HR] = 2.60; 95% confidence interval [CI] = 1.20-5.80). No evidence for interaction between TD and overall or abdominal obesity with risk of death (P_interaction ≥ .80). However, only after comparing men with TD and abdominal obesity with men without TD and no abdominal obesity, we found a 3.30 fold increased risk of death (HR = 3.30, 95% CI = 1.21-8.71).

CONCLUSION

Men with co-occurrence of TD and abdominal obesity have a higher risk of mortality. The effect of co-occurrence of TD and abdominal obesity should be further explored with a larger and longer follow-up time study.

Efficacy, Safety and Immunogenecitystudy of Intravenous Infusion of Rituximab (Hetero) and Reference Medicinal Product (Rituximab, Roche) in Indian Patients of Follicular Lymphoma Preliminary report (HERILY)

OBJECTIVE

To compare the antitumor efficacy, safety, and pharmacodynamics (PD) characteristics of Hetero-Rituximab (test) with Reference Medicinal Product (Rituximab, Roche) in Non-Hodgkin's Lymphoma (NHL).

PATIENTS AND METHODS

Total 40 Follicular Lymphoma (FL) patients were randomized to receive intravenous infusion of either test or reference product. Efficacy (best overall response [BOR] rate [primary end point]), safety, PD (CD19), and immunological assessments (secondary end points) were done at the end of cycle 3 and cycle 6.

RESULTS

Out of 40 patients randomized, 17 were in test arm while 23 were in reference arm. At the end of 6 cycles, BOR (complete response [CR] and partial response [PR]) rate was 64.71% (n=11) in Hetero Rituximab compared to the 43.48% (n=10) in reference arm. The difference between test and reference proportions of best overall response rate at cycle 6, lies within the pre-specified limit for noninferiority. Anti-Rituximab antibodies were found to be negative at cycle 3 and cycle 6 for all FL patients. The FL patients who were treated with Hetero Rituximab, showed significant depletion in CD19+ cell which was comparable with Reference drug. Safety and Immunogenic potential of the test drug was comparable to the reference drug in the patients of FL.

CONCLUSION

Best overall response rate at Cycle 3, Cycle 6 and end of the study lies within the pre-specified limit for non-inferiority which concludes that test product is therapeutically non-inferior to reference medicinal product.

Screening adherence and cancer risk perceptions in colorectal cancer survivors with Lynch-like syndrome

Cancer screening recommendations for patients with Lynch-like syndrome (LLS) are not well defined. We evaluated adherence to Lynch syndrome (LS) screening recommendations, cancer risk perceptions, and communication within the families among colorectal cancer (CRC) survivors with LLS. Thirty-four participants with LLS completed a questionnaire about risk perception, adherence to LS screening recommendations, and communication with relatives. Clinical data were obtained from medical records. Most participants (76%) believed they should undergo colonoscopy every 1-2 years. Only 41% correctly interpreted their genetic tests as uninformative negative or as variant of unknown significance for LS. Less than half had had an upper gastrointestinal endoscopy for screening purpose. Among female participants, 86% had been screened for endometrial cancer (EC) and 71% for ovarian cancer. Most participants had informed relatives about the CRC diagnosis and advised them to undergo CRC screening, but only 50% advised female relatives to be screened for EC and only one-third advised relatives to have genetic counseling. Most CRC survivors with LLS follow the same cancer screening recommended for LS patients but do not understand the meaning of LLS. Greater care must be devoted to communicating the implications of nondiagnostic germline mutation testing among patients with LLS.

Combination angiotensin converting enzyme and direct renin inhibition in heart failure following experimental myocardial infarction

AIMS

Diminishing the activity of the renin-angiotensin system (RAS) plays a pivotal role in the treatment of heart failure. In addition to angiotensin converting enzyme (ACE) inhibitors and angiotensin-receptor blockers, direct renin inhibition has emerged as a potential adjunctive treatment to conventional RAS blockade. We sought to determine the effectiveness of this strategy after myocardial infarction (MI) in the setting of preexisting hypertension, a common premorbid condition in patients with ischemic heart disease.

METHODS AND RESULTS

Ten-week-old female heterozygous hypertensive (mRen-2)27 transgenic rats (Ren-2), were randomized to one of five groups (n = 8 per group); sham, MI, MI + aliskiren, MI + lisinopril and MI + combination lisinopril and aliskiren. Cardiac function was assessed by echocardiography and in vivo cardiac catheterization. Untreated MI animals developed heart failure with hypotension, dilation, reduced ejection fraction (EF), and raised left ventricular end-diastolic pressure (LVEDP). Treatment with single agent treatment had only modest effect on cardiac function though combination therapy was associated with significant improvements in EF and LVEDP when compared to untreated MI animals (P < 0.05). Histologic analysis demonstrated increase extracellular matrix deposition and cardiomyocyte hypertrophy in the noninfarct region of all MI groups when compared with sham operated animals (P < 0.05) that was reduced by ACE inhibitor monotherapy and combination treatment but not by aliskiren alone.

CONCLUSION

In a hypertensive rat model that underwent experimental MI, EF, and LVEDP, key functional indices of heart failure, were improved by treatment with combination ACE and direct renin inhibition when compared with either agent used alone.

Chylopericardium in a child with impaired venous access following small bowel transplantation

A 10-yr-old child with impaired venous access (bilateral occlusion of internal jugular veins, subclavian veins, and inominate veins) underwent an isolated small bowel transplant. He presented with lethargy, shortness of breath 13 months into his follow-up and was diagnosed to have chylopericardium. MR venography and lymphangiography could not demonstrate the site of lymphatic leak. His chyloperciardium was treated with pericardiocentesis and MCT diet. The most likely cause for the chylopericardium was venous occlusion of the subclavian veins with backpressure resulting in a lymphatic leak. A brief review of literature along with treatment options is discussed.

Cetuximab plus irinotecan in pretreated metastatic colorectal cancer patients: the ELSIE study

AIM

To evaluate the efficacy and safety of cetuximab plus irinotecan in irinotecan-refractory metastatic colorectal cancer (mCRC) patients from South-East Asia and Australia.

METHODS

In this open-label, phase II study, the main eligibility criteria were epidermal growth factor receptor-positive mCRC with progressive disease within 3 mo of an irinotecan-based regimen as the most recent chemotherapy. Patients received cetuximab 400 mg/m2 initially, then 250 mg/m2 every week, with the same regimen of irinotecan on which the patients had progressed (4 pre-defined regimens allowed). The primary objective was evaluation of progression-free survival (PFS) at 12 wk. Secondary objectives included a further investigation of PFS, and an assessment of the overall response rate (ORR), duration of response, time to treatment failure (TTF), overall survival and the safety profile.

RESULTS

One hundred and twenty nine patients were enrolled from 25 centers in the Asia-Pacific region and of these 123 received cetuximab plus irinotecan. The most common recent irinotecan regimen used was 180 mg/m2 every 2 wk which had been used in 93 patients (75.6%). The PFS rate at 12 wk was 50% (95% confidence interval (CI, 41-59) and median PFS time was 12.1 wk (95% CI: 9.7-17.7). The ORR was 13.8% (95% CI: 8.3-21.2) and disease control rate was 49.6% (95% CI: 40.5-58.8). Median duration of response was 31.1 wk (95% CI: 18.0-42.6) and median overall survival was 9.5 mo (95% CI, 7.5-11.7). The median TTF was 11.7 wk (95% CI: 9.1-17.4). Treatment was generally well tolerated. The most common grade 3/4 adverse events were diarrhea (13.8%), neutropenia (8.9%), rash (5.7%) and vomiting (5.7%).

CONCLUSION

In patients from Asia and Australia, this study confirms the activity and safety of cetuximab plus irinotecan observed in previous studies in Europe and South America.

Cetuximab plus irinotecan in pretreated metastatic colorectal cancer patients: The ELSIE study

AIM: To evaluate the efficacy and safety of cetuximab plus irinotecan in irinotecan-refractory metastatic colorectal cancer (mCRC) patients from South-East Asia and Australia.

METHODS: In this open-label, phase II study, the main eligibility criteria were epidermal growth factor receptor-positive mCRC with progressive disease within 3 mo of an irinotecan-based regimen as the most recent chemotherapy. Patients received cetuximab 400 mg/m² initially, then 250 mg/m² every week, with the same regimen of irinotecan on which the patients had progressed (4 pre-defined regimens allowed). The primary objective was evaluation of progression-free survival (PFS) at 12 wk. Secondary objectives included a further investigation of PFS, and an assessment of the overall response rate (ORR), duration of response, time to treatment failure (TTF), overall survival and the safety profile.

RESULTS: One hundred and twenty nine patients were enrolled from 25 centers in the Asia-Pacific region and of these 123 received cetuximab plus irinotecan. The most common recent irinotecan regimen used was 180 mg/m² every 2 wk which had been used in 93 patients (75.6%). The PFS rate at 12 wk was 50% (95% confidence interval (CI, 41-59) and median PFS time was 12.1 wk (95% CI: 9.7-17.7). The ORR was 13.8% (95% CI: 8.3-21.2) and disease control rate was 49.6% (95% CI: 40.5-58.8). Median duration of response was 31.1 wk (95% CI: 18.0-42.6) and median overall survival was 9.5 mo (95% CI, 7.5-11.7). The median TTF was 11.7 wk (95% CI: 9.1-17.4). Treatment was generally well tolerated. The most common grade 3/4 adverse events were diarrhea (13.8%), neutropenia (8.9%), rash (5.7%) and vomiting (5.7%).

CONCLUSION: In patients from Asia and Australia, this study confirms the activity and safety of cetuximab plus irinotecan observed in previous studies in Europe and South America.

Abstract 2766: Multicenter pharmacokinetic evaluation of ON 01910. Na, a novel broad-spectrum anticancer agent, in Phase I single agent clinical trials in patients with solid tumors

Introduction: ON 01910. Na is an anti-cancer agent with demonstrated activity against both solid tumors and hematological cancers. The purpose of this research was to evaluate the effect of dose and administration schedule on ON 01910. Na pharmacokinetics (PK) in advanced, heavily pre-treated solid tumor patients. Methods: Data was collected in three Phase I protcols conducted in the US and in India covering a wide range of doses and intraveous infusion schedules: Protocol 1 (50-1375 mg/m2/day over 72 h); Protocol 2 (250 – 4450 mg/m2/day over 24 h) and Protocol 3 (2400-3200 mg over 2, 4 or 8 h). In several patients, pharmacokinetics were evaluated for more than 1 dosing cycle. Plasma samples were collected pre-dose and up to 72 hours post-infusion. ON 01910. Na plasma levels were determined by a validated LC/MS/MS method. Results: Ninety-five data sets from 81 patients were evaluated in this study. ON 01910. Na showed biphasic elimination from the plasma, regardless of dose and administration schedule. The functional half-life of ON 01910. Na, estimated from the initial decline of plasma levels following infusion termination, was less than 2 hours. This was confirmed in data from patients receiving prolonged infusions as ON. 01910. Na approached steady state levels within several hours after dose initiation. As noted in the table below, ON. 01910. Na clearance was lower at higher drug dosing rates. There were no differences in drug pharmacokinetics among the infusion schedules. Conclusion: The pharmacokinetics of ON 01910. Na is dose dependent. A continuous IV infusion would be recommended to treat patients because of its short plasma half-life and rapid clearance. Systemic drug exposure is not affected by type of dosing (flat dosing vs. BSA adjusted). No significant differences were noted between the PK profiles of patients in the US centers and the patients in the India centers.Effect of Dosing Rate on Clearance of ON 01910. NaDosing Rate (mg/m2/hr)NClearance (L/hr/m2)0-25189.3 ± 4.725-501610.0 ± 5.050-75209.2 ± 3.175-10065.5 ± 2.6100-200126.2 ± 3.8200-40083.3 ± 1.6400-800112.5 ± 1.8800-125041.9 +/− 0.47

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 2766.

The prevalence of insulin receptor antibodies in patients with systemic lupus erythematosus and related conditions

Autoantibodies to the insulin receptor have been demonstrated to antagonize the physiologic actions of insulin, most often resulting in hyperglycemia unresponsive to massive doses of insulin (type B insulin resistance). Patients with these anti-insulin receptor antibodies typically have a coexistent autoimmune disorder, most commonly systemic lupus erythematosus (SLE) or undifferentiated autoimmune syndromes. Attempting to determine the prevalence and significance of anti-insulin receptor antibodies, sera from consecutive patients with SLE and early undifferentiated connective tissue disease (UCTD) were tested for the presence of anti-insulin receptor antibodies by radio-immuno assay. Thirty-eight patients participated in the study. Twenty-six had SLE and 12 had UCTD. One patient with SLE (2.6%) was positive for anti-insulin receptor antibodies. None of the patients demonstrated evidence of insulin resistance, hypoglycemia, ovarian hyperandrogenism, or acanthosis nigricans, findings commonly linked with the presence of anti-insulin receptor antibodies. The results presented here indicate that the incidence of anti-insulin receptor antibodies in patients with SLE or UCTD, without associated history of altered glucose metabolism, is quite low. Because in most cases the disturbance of glucose metabolism dominates the clinical picture at presentation and the associated systemic autoimmune syndrome presents either simultaneously with or subsequent to the diagnosis of diabetes, the measurement of anti-insulin receptor antibodies should be reserved for patients with indications of disordered glucose homeostasis.

Adding oral talactoferrin to first-line NSCLC chemotherapy safely enhanced efficacy in a randomized trial

7095

Background: Talactoferrin alfa (TLF) is an oral immunomodulatory protein with a novel mechanism. TLF showed preclinical anti-cancer activity alone and in combination with chemotherapy. In Phase I/II trials, TLF was safe with apparent single-agent anti-cancer activity in non-small cell lung cancer (NSCLC). Methods: 110 chemo-naive patients with advanced or metastatic NSCLC were randomized (1:1) in a multi-center trial to carboplatin/paclitaxel (C/P) therapy plus either TLF or placebo. Starting the day after C/P (C:AUC 5 mg/mL/min; P:175 mg/m2) in chemo-cycles 1, 3 and 5, oral TLF (1.5 g BID) or placebo was administered in 35-day cycles for up to three cycles or until progression. Primary endpoint was Confirmed Response Rate (RR; PR+CR) by CT using RECIST. Secondary endpoints included Progression Free Survival (PFS) and Overall Survival (OS). Results: Baseline patient and disease characteristics were comparable in both groups. All 110 patients were included in the Intent To Treat (ITT) population. 100 patients with at least one CT scan after starting treatment were prospectively defined as the Evaluable population. Adding oral TLF to C/P enhanced efficacy on all endpoints examined including RR, PFS and OS. Confirmed RR in the 100 evaluable patients significantly increased from 29% to 47% (P = 0.05). Confirmed RR in the 110 ITT patients improved from 27% to 42% (P = 0.08). Median PFS in both evaluable and ITT patients improved by 2.8 months (67%). Median OS improved by 31% and 18% in evaluable and ITT patients, respectively. A landmark analysis comparing survival in patients with and without a PR showed a significant difference (P < 0.01), suggesting a strong association between RR and survival. TLF appeared to be very safe and well tolerated with no drug-related SAEs. Fewer AEs were observed in the TLF arm than in the placebo arm, 346 and 432 AEs, respectively (P = 0.0023). The number of Grade 3/4 AEs was also lower in the TLF arm, 60 versus 91 (P = 0.0144). Conclusions: Adding oral TLF to standard C/P chemotherapy in NSCLC was safe and increased efficacy in a randomized, multi-center, double-blind, placebo-controlled trial, with apparent improvements in RR, PFS and OS. Results with TLF compare favorably to other anti-cancer agents. Oral TLF will be further evaluated in a Phase III trial.

[Table: see text]

Treatment of acute lymphoblastic leukaemia in countries with limited resources; lessons from use of a single protocol in India over a twenty year peroid

In the 1970s, survival rates after treatment for acute lymphoblastic leukaemia (ALL) in children and young adults (less than 25 years) in India were poor, even in specialised cancer centres. The introduction of a standard treatment protocol (MCP841) and improvements in supportive care in three major cancer centres in India led to an increase in the event-free survival rate (EFS) from less than 20% to 45-60% at 4 years. Results of treatment with protocol MCP841 between 1984 and 1990 have been published and are briefly reviewed here. In addition, previously unpublished data from 1048 patients treated between 1990 and 1997 are reported. Significant differences in both patient populations and treatment outcome were noted among the centres. In one centre, a sufficiently large number of patients were treated each year to perform an analysis of patient characteristics and outcome over time. Although steady improvement in outcome was observed, differences in the patient populations in the time periods examined were also noted. Remarkably, prognostic factors common to all three centres could not be defined. Total white blood cell count (WBC) was the only statistically significant risk factor identified in multivariate analyses in two of the centres. Age is strongly associated with outcome in Western series, but was not a risk factor for EFS in any of the centres. Comparison of patient characteristics with published series from Western nations indicated that patients from all three Indian centres had more extensive disease at presentation, as measured by WBC, lymphadenopathy and organomegaly. The proportions of ALLs with precursor T-cell immunophenotypes, particularly in Chennai, were also increased, even when differences in the age distribution were taken into consideration (in <18-year olds, the range was 21.1-42.7%), and in molecular analyses performed on leukaemic cells from over 250 patients less than 21-years-old with precursor B-cell ALL, a lower frequency of TEL-AML1-positive ALL cases than reported in Western series was observed. The worse outcome of treatment in Indian patients compared with recent Western series was probably due to the higher rate of toxic deaths in the Indian patients, and possibly also due to their more extensive disease - which is, at least partly, a consequence of delay in diagnosis. Differences in the spectrum of molecular subtypes may also have played a role. The higher toxic death rates observed are likely to have arisen from a combination of more extensive disease at diagnosis, co-morbidities (e.g., intercurrent infections), differences in the level of hygiene achievable in the average home, poor access to acute care, and more limited supportive care facilities in Indian hospitals. Toxic death was not associated with WBC at presentation, and hence would tend to obscure the importance of this, and, potentially, other risk factors, as prognostic indicators. Since the prevalence of individual risk factors varies in different populations and over time, their relative importance would also be expected to vary in different centres and in different time periods. This was, in fact, observed. These findings have important implications for the treatment of ALL in countries of low socioeconomic status; it cannot be assumed that risk factors defined in Western populations are equally appropriate for patient assignment to risk-adapted therapy groups in less affluent countries. They also demonstrate that heterogeneity in patient populations and resources can result in significant differences in outcome, even when the same treatment protocol is used. This is often overlooked when comparing published patient series.

Identification of various MLL gene aberrations that lead to MLL gene mutation in patients with acute lymphoblastic leukemia (ALL) and infants with acute leukemia

Studies were done to investigate MLL gene aberrations using Conventional Cytogenetics, Southern blotting as well as FISH using a panel of probes on 218 cases which included 206 cases of pediatric/young adult ALL and 12 cases of infantile acute leukemias from Tata Memorial Hospital, India. The incidence of MLL gene rearrangements in acute lymphoblastic leukemia (ALL) was 9.4% which included infants as well as pediatric/young adults. In infantile group which included ALL as well as AML cases, MLL gene rearrangement was very common (75% frequency). Application of metaphase-FISH helped unravel MLL rearrangements not only as a result of translocations but also inversions, insertions, partial deletion, duplications, partial duplication-->self-fusion. Besides age, MLL gene rearrangements showed significant association with hyperleukocytosis, peripheral blood blast percentage and early Pre-B phenotype. Clinical outcome of patients with MLL gene rearrangements revealed unfavorable prognosis.

Report of an International Network of Cancer Treatment and Research workshop on non-Hodgkin's lymphoma in developing countries

The International Network of Cancer Treatment and Research (INCTR) recently organized a workshop on non-Hodgkin lymphomas (NHLs) in selected developing countries with the purpose of examining existing information relating to the pathology and management of these neoplasms, and identifying potential areas for research. This report provides a summary of the information presented and is focused primarily on the pathology of NHLs in children and adults. In most countries, the WHO classification of lymphomas was used and most participating centers included immunohistochemistry using a wide array of lymphoid antibodies as part of routine diagnosis. Some of the series had been reviewed by an external panel of experts. B-cell lymphomas accounted for 82-88% of all NHLs. The proportions of chronic lymphatic leukemia (4-6%), mantle cell lymphoma (MCL, 3-5%), and plasmacytoma (2-4%) were similar in the series presented. However, there was a significant variation in the proportion of follicular lymphoma (FL), which accounted for 15% and 11% in India and Kuwait, but less than 5% in Pakistan and Egypt. All of these frequencies are significantly lower than those reported in Western series. Diffuse large B-cell lymphoma accounted for about 35% of cases in India but for more 50% in other countries, but this difference was not accounted for by an increased incidence in a single lymphoma subtype in India, but rather an apparent paucity of several subtypes (such as mantle cell and marginal zone lymphomas (MZL)) in other series. There were relatively high frequencies of Burkitt lymphoma in Egypt (7%) and precursor T-cell lymphoblastic lymphoma in India (6-7%). Peripheral T-cell lymphomas (PTCLs) (not otherwise specified and angioimmunoblastic subtypes) accounted for 3-5% of NHLs, and extranodal lymphoma of T/NK cell type was rare (<1%). These differences in the relative proportions of NHL subtypes among developing countries and between developing countries and the rest of the world presumably arise from differences in environmental and genetic factors that influence lymphomagenesis and strongly suggest that more research in developing countries would provide valuable insights into the pathogenesis of lymphoid neoplasms.

Constitutional genomic instability, chromosome aberrations in tumor cells and retinoblastoma

Although retinoblastoma (Rb) is initiated as a result of biallelic inactivation of the RB1 gene, additional genetic events (M3) in tumor cells are indicative of their role in the full transformation of retinal cells. We investigated the constitutional genetic instability by fragile site (FS) expression studies and checked its relationship with loci of tumor cytogenetics in a series of 36 retinoblastoma patients (34 nonfamilial and 2 familial cases). Tumor cytogenetics revealed -13/+13, del/t(13)(q14) (50%), +1/del/t(1p/q) (65%), +6/i(6p) (60%), and del(16)(q13)/(q22 approximately q23) (60%). Conventional cytogenetics in leukocytes revealed constitutional del(13q14) in five unilateral Rb (URB) and one trilateral Rb (TRB). Constitutional del(16)(q22) and t(6;12) were also identified in two cases. Constitutional FS analysis showed a significant increase in the cellular fragility, with high prevalence at 13q14, 3p14, 6p23, 16q22 approximately q23, and 13q22 loci in retinoblastoma patients (P<0.05). Patients with constitutional del(13)(q14) demonstrated higher fragility than those with normal constitution. A strong correlation between loci of constitutional FSs and loci of recurrent chromosomal abnormalities in tumors strengthen and support the proposal that FS loci present as inherent genomic instability in retinoblastoma. The chromosomal changes and resultant genetic mutations, along with RB1 mutation events, probably contribute synergistically to the development and progression of Rb malignancy. Implementation of fluorescence in situ hybridization to nonfamilial Rb on a large scale (113 cases) could detect constitutional RB1 deletion in 12.3% of cases, with equally higher incidence in URB (14.7%) and bilateral Rb (13.6%), demonstrating that the true prevalence of patients with predisposition to RB1 mutation in sporadic URB is definitely higher in our populations. Also, higher incidence of constitutional RB1 deletion mosaicism in unilateral than in bilateral Rb indicates that the constitutional genetic mosaicism in URB should be given serious consideration during genetic counseling.

Clonal T-cell receptor gamma and delta gene rearrangements in T-cell acute lymphoblastic leukemia at diagnosis: predictor of prognosis and response to chemotherapy

Risk-based treatment assignment requires the availability of prognostic factors that reliably predict clinical outcome. Junctional regions of T-cell receptor (TCR) genes provide the best tool to study clonality, lineage association and minimal residual disease (MRD) in T-ALL. In this study, we have analyzed the suitability of clonal TCR gamma and delta junctional gene rearrangement status of T-ALL patients at diagnosis as a prognostic marker for T-ALL. We studied peripheral blood samples of 50 newly diagnosed patients with T-ALL in India for incidence of clonal TCR gamma and delta junctional region gene rearrangements by PCR-coupled heteroduplex analysis. Of these, 17 T-ALL patients uniformly treated on MCP 841 protocol were followed for more than 40 months (range: 41.26-55.82 months; mean: 49.26) and their clonal TCRgammadelta genotype was correlated with clinical outcome with respect to duration of complete remission, disease-free survival (DFS) and event-free survival. We also compared the clinical and biological features of TCRgammadelta + T-ALL and TCRalphabeta + T-ALL for their relative order of significance. Thirty per cent (15 of 50) of Indian T-ALL patients exhibited clonal rearrangements of both TCR gamma and delta genes. A significant proportion of these patients (73.3%, 11 of 15 P < 0.005) showed predominant usage of VgammaI-Jgamma1.3/2.3 with Vdelta1-Jdelta1 genes. A statistically significant association of L2 and L1 FAB blast morphology with TCRgammadelta + T-ALL and TCRalphabeta + T-ALL, respectively was observed (P = 0.001 by Fisher's Exact Test). The survival rate in DFS group was higher for TCRgammadelta + T-ALL compared to TCRalphabeta + T-ALL (P = 0.1378 by Log rank test). Thus we have identified clonal TCR gamma and delta junctional gene rearrangement status of T-ALL patients at diagnosis as a prognostic marker and predictor of response to chemotherapy. In future, this may help in designing tailored and risk-adjusted (less aggressive and less toxic) therapies for subset of T-ALL patients.

Chromosomal rearrangement in Down syndrome with acute myeloid leukemia

The incidence of acute leukemia in children with Down syndrome (DS) is high as compared to general population. Recent findings have demonstrated that DS children with acute myeloid leukemia (AML) have the highest event free survival rates with high dose cytosine arabinoside (Ara-C). We present 3 year-old DS female child with AML-M5, whose chromosomal analysis revealed constitutional t(21;21) alongwith del(5)(q31q33) and a unique translocation t(16;20)(q13;q12). After chemotherapy, child achieved complete clinical remission. Karyotype analysis of remission marrow showed disappearance of abnormal clone of der(20) t(16;20)(q13;q12), del(5q) indicating cytogenetic remission too. This case alongwith supportive literature indicate that pediatric DS-AML is a distinct biologic sub-group differs from that of non-DS-AML with respect to chemosensitivity.

Passive active prophylaxis against Hepatitis B in children with acute lymphoblastic leukemia

The aim of this study was to assess the antibody response to combined passive active immunisation versus active immunisation along with interferon against Hepatitis B in 60 patients with acute lymphoblastic leukemia (ALL) between 1 and 21 years of age with negative Hepatitis B virus (HBV) serology at presentation. Thirty-one patients received combined passive active immunisation with human specific Hepatitis B immunoglobulin (HEPABIG-VHB Pharmaceuticals) and Hepatitis B vaccine (arm I) and 29 patients received active immunisation along with interferon (arm II). Protective antibody levels were detected in 89.6 and 21% patients, respectively, at the 6-month evaluation. Infection with HBV occurred in 17 and 59% patients, respectively, at the 6-month evaluation. Interferon, thus, failed to serve the role as a vaccine adjuvant. At the 9-month evaluation of patients who received immunoglobulin, protective antibody titers were lost in 8 out of 19 evaluable patients (42%) and of these, 3 patients became HBsAg reactive at this point of time. This study indicated that 47.3% patients undergoing aggressive chemotherapy responded to combined passive active prophylaxis with protective titers of antiHBs at the 9-month evaluation. However, the rate of HBV infection was greatly reduced to 27%. We suggest that usage of passive immunisation in the aggressive phase, followed by active immunisation after cessation of intense chemotherapy would be a better option to increase the rates of protective antibody levels in these immunocompromised patients with leukemia.

Fluorescence in situ hybridization: a highly efficient technique of molecular diagnosis and predication for disease course in patients with myeloid leukemias

The accuracy of cytogenetic diagnosis in the management of hematological malignancies has improved significantly over the past 10 years. Fluorescence in situ hybridization (FISH), a technique of molecular cytogenetics, has played a pivotal role in the detection of unique sub-microscopic chromosomal rearrangements that helped in the identification of chromosomal loci, which contain genes involved in leukemogenesis. We studied the feasibility and sensitivity of the FISH technique for molecular analysis of translocations markers, t(9;22) and t(15;17) for accurate molecular diagnosis and for monitoring the disease in 21 patients with chronic myeloid leukemia (CML) who received interferon-alpha and/or chemotherapy (7 patients), bone marrow transplantation (14 patients), and 14 patients with acute promyelocytic leukemia (APL) who received all-trans-retinoic acid (ATRA) and/or chemotherapy. We also applied conventional karyotyping (CK) for identification of t(9;22) and t(15;17) at diagnosis. All CML cases had a Ph; t(9;22) and except for two cases all APL had t(15;17). The FISH studies on CML marrows in complete cytogenetic remission (CCR) (100% Ph- by CK) achieved by IFN-alpha, showed 0-2.5% of cells with BCR-ABL fusion in first cytogenetic remission (Controls, range 0.5-1.5%). Repeat follow-up FISH studies could be done in two cases in remission, which demonstrated 0-10% of cells with BCR-ABL fusion. Evaluation of Ph positive status of CML marrow at diagnosis by CK (100% Ph+ cells) and FISH (80-92% BCR-ABL fusion) pointed the existence of dormant clone of normal residual hematopoietic cells along with actively proliferating clones of Ph positive cells. Fluorescence in situ hybridization analysis of post-BMT CML marrows in CCR (0% Ph+ mitoses) could detect MRD with range of 1-6%. Among 14 patients, 9 who showed percentage of BCR-ABL positive cells (0.0-1.5%) almost similar to normal controls, 6 patients had comparatively good prognosis (disease-free survival 7-14 months). Of five patients with residual leukemic cells in the range of 2-6%, 4 relapsed within a period of 3-24 months. Fourteen APL patients in CCR [100% t(15;17) negative cells by CK] were evaluated by FISH to check the presence of residual leukemic cells. In these patients FISH could efficiently detect 1-14.5% of residual cells with PML-RARA (patients mean MRD 5%, controls mean MRD 3.5%, P=.02). Since the time of FISH analysis, 5 to 7 patients with higher fraction of leukemic cells (5-11%) relapsed within a short period (1-7 months). On the contrary, 5 of 7 patients with either absence or low percentage of PML-RARA positive cells remained in complete remission for 11-24 months. Our data show that FISH has a potential to detect and measure the fraction of aberrant malignant cells in remission marrows, induced by BMT in CML and chemotherapy in APL. These findings encourage the investigations on a large scale to merit its potential for identification of patients at high risk. In the present studies, FISH on interphase cells also demonstrated its efficiency in the molecular diagnosis by its ability to detect BCR-ABL and PML-RARA fusion in CML with masked/variant Ph and t(15;17) negative APL, respectively. The efficiency of technique in molecular diagnosis was also proved in one of the CML patients who progressed to myeloid blastic phase where interphase FISH could identify an extra BCR-ABL fusion on both chromosomes 9 indicating insertion of BCR into ABL and its duplication.

Inhibition of glioma cell growth and tumorigenic potential by CCN3 (NOV)

AIMS

To establish whether the ectopic expression of CCN3 (NOV) in glioma cells can interfere with their tumorigenic potential and assess its potential value in molecular medicine.

METHODS

Glioma cell lines were used to assess whether differences in the degree of intracellular communication induced by the expression of the gap junction protein connexin 43 (Cx43) is related to the differential expression of CCN3 (NOV). The antiproliferative activity of rat CCN3 (rCCN3; NOV) in glioma cells, has been assessed both in vitro and in vivo with glioma cell lines expressing different amounts of CCN3 (NOV).

RESULTS

Upon ectopic expression of Cx43, the growth of C6 glioma cells is decreased. An increase of CCN3 (NOV) expression matches the reduced tumorigenic potential of these transfected cells. The localisation of CCN3 (NOV) is affected by the increased expression of Cx43 in the Cx-13 transfected cells, in which it is detected at areas of cell-cell contact. In a xenograft model, CCN3 (NOV) transfected glioma cells were found to induce tumours to a lesser degree than their parental counterparts, which do not express detectable amounts of CCN3 (NOV).

CONCLUSIONS

Previous observations had suggested an inverse relation between CCN3 (NOV) expression in glioma cells and their tumorigenicity. These results establish a direct association between the establishment of functional gap junctional intercellular communication and the expression of rCCN3 (NOV). In addition to a negative effect on murine and human cell growth, CCN3 (NOV) has antiproliferative activity on tumour cells in vivo. Thus, the antiproliferative activity of the CCN3 (NOV) protein might involve reorganisation of cellular contacts that play a crucial role in tumorigenesis. The antiproliferative activity of CCN3 (NOV) established in this work sets the stage for the potential use of CCN proteins in molecular oncology.

Gynecomastia in a case of hairy cell leukaemia--cladribine induced?

Gynecomastia is benign enlargement of the male breast and is commonly drug induced. Various drugs are responsible and chemotherapeutic drugs can also cause gynecomastia. Cladribine is now widely used for the treatment of hairy cell leukaemia. We present a case report of development of unilateral gynecomastia in a case of hairy cell leukaemia treated with cladribine and question whether this was induced by the chemotherapy.

Mycobacterial pulmonary infection post allogeneic bone marrow transplantation

Allogeneic bone marrow transplant recipients are prone to pulmonary infections caused by a wide spectrum of organisms. Since the first bone marrow transplatation (BMT) done in 1983 at the Tata Memorial Hospital, we have recently seen the first case of Mycobacterium Fortuitum Chelonae complex among 117 BMT (including 90 allogeneic and 27 autologous) patients. The patient was on immunosuppressants for chronic GVHD post allogeneic BMT done for CML-CP. He developed pulmonary mycobacterial infection 13 months post BMT. Diagnosis was difficult because of the atypical presentation, negative culture reports, and the presence of multiple pathogens due to immunosuppression. In our case the diagnosis was eventually established after examination of material obtained by bronchoscopy. Patient has shown response to antituberculosis drugs after 2 months. This shows the need to consider atypical mycobacterial infection in the differential diagnosis of pulmonary illness in the post allogeneic BMT setting.

Properties and secondary structure analysis of BanI endonuclease: identification of putative active site

Biochemical properties of Type II restriction enzyme BanI were characterized. Kinetic parameters were evaluated and an enhancement of rate was observed when the recognition site was located in a more central position in the substrate, suggesting that BanI locates its recognition site by a sliding mechanism. As BanI has three cysteine residues in its primary sequence, the effect of thiol inhibitors on BanI activity was also studied. Partial inhibition was observed only at a very high concentration of the inhibitor indicating that cysteine residues are not directly involved in catalysis. The gel electrophoretic mobility shift assay demonstrated specific complex formation between BanI and the DNA substrate in the presence of poly dI-dC and Mg(2+). A secondary structure analysis and comparison with EcoRI and BamHI crystal structure revealed a putative active site similar to that seen in BamHI but different in the order in which the catalytic domain (central beta-sheet) and recognition domain (adjacent alpha-helix) were arranged in the protein.

Differences in the microtubule organization between normal and cml granulocytes after stimulation with chemotactic peptide

Chemotaxis of polymorphonuclear leukocytes (PMNL) from chronic myeloid leukemia (CML) patients followed in a gradient of a chemotactic peptide n-formyl-methionyl-leucyl-phenylalanine (fMLP) is consistently defective in all the phases of the disease. Chemoattractant-induced polymerization of cytoskeletal proteins (actin and tubulin) plays a major role in regulation of cell shape and cellular motility. To study the role of microtubules in defective chemotaxis, we have compared fMLP-induced alterations in organization of microtubules in PMNL from CML patients with those from normal subjects by laser confocal microscopy. Our analysis shows differences in microtubule organization between normal and CML PMNL and suggests that both nucleation of new microtubule and elongation of pre-existing microtubules are essential for PMNL chemotaxis.

Avascular necrosis of head of femur in a patient with acute promyelocytic leukemia

Avascular necrosis (AVN) of head of the femur is associated with various pathological conditions and treatment modalities. We present a case of acute promyelocytic leukemia who was treated with all-transretinoic acid (ATRA), daunomycin, cytarabine and a short course of dexamethasone. He developed AVN of bone after 2 years of treatment. Whether this is related to ATRA is dealt with in the discussion.

BanI restriction endonuclease binds in the major groove of DNA: an inhibition kinetic study using substrates with mismatch basepairs

Structural information on BanI-DNA interaction was obtained from simple inhibition kinetic assays using altered substrates. Self-complementary 13-mer oligodeoxynucleotides with or without mismatch basepairs in the BanI recognition sequence (GGPyPuCC) were synthesized. UV melting curves and CD spectra indicated double-stranded B-DNA structure for all the oligomers. Among the seven oligomers with recognition sequences, GGTACC, GGTGCC, GGTATC, GGCACC, GGAGCC, GGTAAC, and GGATCC, only the first two were cleaved with BanI. Kinetics of BanI cleavage of the native substrate was inhibited competitively by all of the other oligomers except the one with sequence GGCACC. From inhibition kinetic analysis in presence of a fixed concentration of the inhibitor, apparent K(m) and K(I) were determined. The data were analyzed in the context of alterations made in the hydrogen bonding potential in the major and minor groove of DNA within the recognition sequence due to basepair mismatches. Such analyses led to the conclusion that BanI, like BamHI, binds in the major groove and the central thymines make important contact with the protein.

T-cell receptor gamma and delta gene rearrangements in T-cell acute lymphoblastic leukemia in Indian patients

T-cell acute lymphoblastic leukemia (T-ALL) is a clonal lymphoid malignancy and junctional sequences of rearranged T-cell receptor (TCR) represent the best suitable marker to study clonality in these patients. A sensitive, non-radioactive, and rapid approach of PCR coupled with heteroduplex analysis was used to analyse clonality of TCR gamma and delta gene rearrangements in 26 Indian T-ALL patients. Amongst TCR gamma gene family, VgammaI-Jgamma1.3/2.3 sequences were most utilized (53.9%) while from TCRdelta repertoire Vdelta1-Jdelta1 sequences were preferentially rearranged (23.1%) in these patients. 19.2% of Indian T-ALL patients demonstrated both clonal TCR gamma and delta gene rearrangements along with surface expression of TCRgammadelta. Although the majority of T-ALL patients showed surface expression of TCRalphabeta, the small fraction (19.2%) of TCRgammadelta+ T-ALL represent a distinct subgroup which needs further evaluation.

PAX3 and PAX7 exhibit conserved cis-acting transcription repression domains and utilize a common gain of function mechanism in alveolar rhabdomyosarcoma

The t(2;13) and t(1;13) translocations of alveolar rhabdomyosarcoma (ARMS) result in chimeric PAX3-FKHR or PAX7-FKHR transcription factors, respectively. In each chimera, a PAX DNA-binding domain is fused to the C-terminal FKHR transactivation domain. Previously we demonstrated that PAX3-FKHR is more potent than PAX3 because the FKHR transactivation domain is resistant to repression mediated by the PAX3 N-terminus. Here we test the hypothesis that the cis-acting repression domain is a conserved feature of PAX3 and PAX7 and that PAX7-FKHR gains function similarly. Using PAX-specific DNA-binding sites, we found that PAX7 was virtually inactive, while PAX7-FKHR exhibited activity 600-fold above background and was comparable to PAX3-FKHR. Deletion analysis showed that the transactivation domains of PAX7 and PAX7-FKHR are each more potent than either full-length protein, and resistance to cis-repression is responsible for the PAX7-FKHR gain of function. Further deletion mapping and domain swapping experiments with PAX3 and PAX7 showed that their transactivation domains exhibit subtle dose-dependent differences in potency, likely due to regions of structural divergence; while their repression domains are structurally and functionally conserved. Thus, the data support the hypothesis and demonstrate that PAX3 and PAX7 utilize a common gain of function mechanism in ARMS.

Ionizing radiation improves survival in mice bearing intracranial high-grade gliomas injected with genetically modified herpes simplex virus

Malignant gliomas remain incurable with current interventions. Encouraging investigational approaches include the use of genetically modified herpes simplex-1 (HSV-1) viruses as direct cytotoxic agents. Combining attenuated HSV-1 with standard therapy, human U-87 malignant glioma xenografts grown in the hind limb or intracranially in athymic nude mice were exposed to ionizing radiation, inoculated with genetically modified HSV R3616, or received both virus and radiation. The combination of virus with fractionated ionizing radiation suggests a synergistic action and results in reduced tumor volumes and longer survivals when compared with treatment with either modality alone.