Clinical evaluation of DFN3 patients with deletions in the POU3F4 locus and detection of carrier female using MLPA

Song MH, Lee HK, Choi JY, Kim S, Bok J, Kim U‐K. Clinical evaluation of DFN3 patients with deletions in the POU3F4 locus and detection of carrier female using MLPA. X‐linked deafness type 3 (DFN3), the most prevalent X‐linked form of hereditary deafness, is caused by mutations of the POU3F4 locus in the Xq21 region. We evaluated two Korean families showing typical characteristics of DFN3, such as congenital hearing loss and pathognomonic inner ear anomalies. Genetic analysis of these families did not reveal any mutations in the POU3F4 coding sequence. Instead, one family carried a genomic deletion upstream of POU3F4 gene, where the regulatory element is predicted to reside, and the other family possessed a deletion of almost the entire Xq21 region. The lack of mutation in the POU3F4 coding sequence makes the detection of carrier females using conventional sequencing methods difficult. By applying the multiplex ligation‐dependent probe amplification (MLPA) method, we successfully determined the carrier status of female members in these families, demonstrating that MLPA is a rapid and accurate way to detect POU3F4 deletions in sporadic undiagnosed carriers of DNF3.     

Excellent safety and tolerability of the human immunodeficiency virus type 1 pGA2/JS2 plasmid DNA priming vector vaccine in HIV type 1 uninfected adults

A vaccine consisting of DNA priming followed by recombinant modified vaccinia Ankara (rMVA) boosting has achieved long-term control of a pathogenic challenge with a chimera of simian and human immunodeficiency viruses (SHIV-89.6P) in rhesus macaques. Based on these results, clade B HIV-1 DNA and rMVA immunogens have been developed for trials in humans. We conducted a first-time in humans phase I safety trial using the pGA2/JS2 (JS2) HIV-1 DNA priming vector expressing Gag, Pol, Env, Tat, Rev, and Vpu. Thirty HIV-uninfected adults were vaccinated with 0.3 or 3 mg of JS2 DNA, or a saline placebo, by intramuscular injection at months 0 and 2. Both doses of DNA were safe and well-tolerated with no differences between the control, 0.3 mg, or 3 mg groups (n = 6, 12, and 12, respectively) through 12 months of postvaccination follow- up. A chromium-release assay using fresh peripheral blood mononuclear cells (PBMCs) and a validated IFN-gamma ELISpot assay with frozen PBMCs failed to detect CD4(+) or CD8(+) HIV-1-specific T cell responses. HIV-specific neutralizing antibodies were also not detected. The vaccine is being further developed as a priming vector for a combined DNA plus rMVA prime/boost HIV vaccination regimen.     

Comparison of clinical schemas and morphologic features in predicting Lynch syndrome in mutation-positive patients with endometrial cancer encountered in the context of familial gastrointestinal cancer registries

BACKGROUND:

Endometrial cancer (EC) is the most common extraintestinal malignancy in Lynch syndrome (LS) and often is the sentinel malignancy, yet there is no consensus regarding LS‐EC detection algorithms. In this study, the authors determined the efficacy of family/personal history and tumor morphology in predicting LS in a cohort of patients with EC who had mutation‐proven LS.

METHODS:

Amsterdam II (AmII) criteria, revised Bethesda guidelines (rBG), and Society of Gynecologic Oncologists (SGO) clinical screening criteria were applied to the pedigrees of 76 patients with mutation‐proven LS who had pathology‐proven EC. When tumors were tested for microsatellite instability (MSI) phenotype status or mismatch‐repair protein‐immunohistochemical (MMR‐IHC) expression, those results also were reviewed, and LS‐associated histopathologic features were documented in 38 available patients.

RESULTS:

Of 76 patients, 36%, 58%, 71%, and 93% would have been selected for further testing for LS by pedigree screening at the time of EC diagnosis with rBG, AmII, SGO 20%‐to‐25%, and SGO 5%‐to‐10% criteria, respectively. Ninety percent (18 of 20 tumors) of tested ECs had high MSI, and 96% (22 of 23 tumors) had abnormal MMR‐IHC expression. At least 1 LS‐EC morphologic feature was present in 16 of 38 tumors (42%).

CONCLUSIONS:

Clinical screening criteria had variable efficacy for the identification of LS‐associated EC, and SGO 5%‐to‐10% criteria performed best. Characteristic pathologic features were present in a minority of patients. Although a high proportion of LS‐ECs had the MSI phenotype and were MMR deficient, the specificity of these tests and of clinical screening for LS in unselected patients with EC has been poorly described. Prospective studies to determine the optimal combination of these screening modalities are required. Cancer 2012;. © 2011 American Cancer Society.     

Mutation and deletion analysis of GFR alpha-1, encoding the co-receptor for the GDNF/RET complex, in human brain tumours.

Glial cell line-derived neurotrophic factor (GDNF) plays a key role in the control of vertebrate neuron survival and differentiation in both the central and peripheral nervous systems. GDNF preferentially binds to GFRalpha-1 which then interacts with the receptor tyrosine kinase RET. We investigated a panel of 36 independent cases of mainly advanced sporadic brain tumours for the presence of mutations in GDNF and GFRalpha-1. No mutations were found in the coding region of GDNF. We identified six previously described GFRalpha-1 polymorphisms, two of which lead to an amino acid change. In 15 of 36 brain tumours, all polymorphic variants appeared to be homozygous. Of these 15 tumours, one also had a rare, apparently homozygous, sequence variant at codon 361. Because of the rarity of the combination of homozygous sequence variants, analysis for hemizygous deletion was pursued in the 15 samples and loss of heterozygosity was found in 11 tumours. Our data suggest that intragenic point mutations of GDNF or GFRalpha-1 are not a common aetiologic event in brain tumours. However, either deletion of GFRalpha-1 and/or nearby genes may contribute to the pathogenesis of these tumours.