Cytogenetic and molecular genetic analysis of tumorigenic human bronchial epithelial cells induced by radon alpha particles

To establish a cell culture model for lung carcinogenesis, independent populations of the human papillomavirus 18-immortalized human bronchial epithelial cell line BEP2D were treated with high linear energy transfer radon-simulated alpha-particles, expanded and xenotransplanted into Nu/Nu mice. Six independent cell lines were established from tumors that developed from three separate radiation treatments as follows: treatment (Tx) 1 (30 cGy--two doses), H2BT, Tx 2 (30 cGy-- single dose), R30T1L, R30T2 and R30T3L, Tx 3 (30 cGy--single dose), H1ATN and H1ATBA1. Cytogenetic analysis revealed common changes in all tumor lines: loss of the Y chromosome (ch), one of three copies of ch8, one of three copies of ch14, and one of two copies of ch4p16-pter and ch11p15-pter. Analysis of polymerase chain reaction-amplified short tandem repeats of informative loci confirmed the loss of chY in all lines and loss of heterozygosity (LOH) at eight loci spanning the length of ch8 in all lines from Tx's 1 and 2. Our data support previous studies indicating the presence of tumor suppressor genes on ch8. LOH also was confirmed on ch14 at locus D14S306 in all cell lines from Tx 2 and in one of two lines from Tx 3. This region, 14q12-q13, may contain changes in one of the five known somatostatin receptor genes (SSTR1). No LOH was detected at any of the informative loci tested for on ch4 or ch11.      

Management of Rh-isoimmunised Pregnancies : Our Experience

Background

The aim of this study was to assess the role of middle cerebral artery peak systolic velocity (MCA-PSV), as measured by doppler ultrasound, in detecting foetal anaemia in Rh- isoimmunised pregnancies. Intra-uterine foetal blood transfusion was performed in such anaemic foetuses to tide over the crisis of foetal immaturity till considered fit for extra-uterine survival.

Methods

Rh-isoimmunised pregnancies reporting to a tertiary institute from 2003 to 2005, were screened by doppler ultrasound to estimate MCA-PSV to detect foetal anaemia. If the foetus developed MCA-PSV of more than 1.5 multiple of median (MoM) for the gestational age, foetal blood sampling through cordocentesis was performed to confirm foetal anaemia, followed by intrauterine foetal blood transfusion to all anaemic foetuses at the same sitting. Neonatal outcome was evaluated by recording gestational age at the time of delivery, duration of gestational time gained and need for blood transfusion in the neonatal period.

Results

A total of thirteen isoimmunised pregnancies were evaluated. Three pregnancies did not require in-utero foetal blood transfusion. Twenty-one intrauterine foetal blood transfusions were performed in the remaining ten patients. Five received blood transfusion in the neonatal period. Intra uterine foetal death occurred in one grossly hydropic foetus and favourable neonatal outcome was recorded in the rest.

Conclusion

The clinical outcome of these pregnancies justifies the use of doppler studies of MCA-PSV in detecting foetal anaemia and intra uterine foetal blood transfusion is the only hope of prolonging pregnancy and salvaging such foetuses.Key Words: Rh-isoimmunisation, Middle cerebral artery peak systolic velocity, Foetal anaemia, Foetal blood transfusion     

A novel beta-thalassemia frameshift mutation (codon 14/15), detectable by direct visualization of abnormal restriction fragment in amplified genomic DNA

A new frameshift mutation due to an insertion of G between codon 14/15 of the beta-globin gene was found in two unrelated Chinese patients with Cooley's anemia. The first patient (W.S.) was homozygous for haplotype 5 (Chinese) and carried a codon 41/42 (four base pair deletion) mutant, while the second patient (C.K.) was homozygous for haplotype 2 (Chinese), and also had a codon 17 (A----T) nonsense mutation. Molecular cloning and M13 sequencing of the beta gene in patient W.S. revealed that the new mutant was found in a beta-globin gene framework type 3 (Asian). Direct sequencing was performed on polymerase chain reaction-amplified genomic DNA from patient C.K. With the new mutation, an additional BstNI or EcoRII recognition site is generated and the abnormal restriction fragment (134 basepair) can be directly visualized on polyacrylamide gel electrophoresis of the amplified genomic DNA.     

Posterior Superior Mesenteric Artery (SMA) First Approach vs. Standard Pancreaticoduodenectomy in Patients with Resectable Periampullary Cancers: a Prospective Comparison Focusing on Circumferential Resection Margins

Background

The ‘SMA-first’ (P-SMA) pancreatoduodenectomy (PD) allows dissection directly on the right lateral aspect of superior mesenteric artery (SMA) which may decrease circumferential resection margin (CRM) positivity. This comparative study between standard PD (sPD) and P-SMA approach was planned focusing on CRM involvement.

Methods

This was a prospective study comparing consecutive patients with resectable periampullary cancers (PACA) undergoing PD using the standard or P-SMA approach. The perioperative outcomes and the CRM positivity rates (specimens analysed according to the standardized Leeds pathology protocol (LEEPP)) were compared.

Results

Overall, 39 patients (28 men; mean age 54 years; sPD 21, P-SMA 18) were included. Both groups were comparable with regard to demographic/tumour characteristics and perioperative outcomes. The P-SMA technique was significantly faster (321.1 ± 54.0 vs. 357.6 ± 55.8 min; p = 0.05). Though the mean tumour size (2.2 vs. 2.1 cm; p = 0.84) and T stage (T2 and T3) distribution were similar in both groups, lymph node yield was significantly higher in the P-SMA group (10.7 vs. 5.95; p = 0.001; mean 8 (2–21)). Though CRM positivity (margin <1 mm) occurred in 8 (21.1%), we did not find the P-SMA PD to yield significantly lower CRM positivity rates compared to the sPD (3/17 (17.6%) vs. 5/21(23.8%); p = 0.71). At a median follow-up of 28 months, fewer patients in the P-SMA PD group developed recurrence (2/15 vs. 5/19; p = 0.3) or died (3/15 vs. 7/19; p = 0.19), though this difference was not significant.

Conclusions

In patients with resectable PACA, P-SMA PD was significantly faster and yielded higher lymph node counts in the specimen but did not lower the rate of CRM positivity as determined by the LEEPP.

     

Nomogram to Assess the Survival Benefit of New Salvage Agents for Metastatic Urothelial Carcinoma in the Era of Immunotherapy

Introduction

Optimal end points in phase 2 trials evaluating salvage therapy for metastatic urothelial carcinoma are necessary to identify promising drugs, particularly immunotherapeutics, where response and progression-free survival may be unreliable. We developed a nomogram using data from phase 2 trials of historical agents to estimate the 12-month overall survival (OS) for patients to which observed survival of nonrandomized data sets receiving immunotherapies could be compared.