Correlation of cellular immunity with human papillomavirus 16 status and outcome in patients with advanced oropharyngeal cancer

OBJECTIVE

to determine whether the favorable outcome associated with human papillomavirus (HPV) 16-positive oropharyngeal cancer is related to a patient's adaptive immunity.

SETTING

academic medical center.

PATIENTS

forty-seven of 66 previously untreated patients (6 of 20 patients with stage III and 41 of 46 with stage IV cancer) in a prospective clinical trial of chemoradiotherapy.

INTERVENTION

all patients were treated with a single course of neoadjuvant chemotherapy followed by either surgery (for nonresponders) or chemoradiotherapy.

MAIN OUTCOME MEASURES

pretreatment levels (percentages and absolute counts) of CD3, CD4, CD8, natural killer, and B cells and overall white blood cell counts were measured by flow cytometry. Correlations of subsets with HPV-16 status, tumor subsite, cancer stage, T class, N class, smoking status, performance status, sex, response to chemoradiotherapy, p53 mutation type, epidermal growth factor receptor expression, and disease-specific and overall survival were determined.

RESULTS

after a median follow-up of 6.6 years, improved survival was associated with an elevated percentage of CD8 cells (P = .04), a low CD4:CD8 ratio (P = .01), low epidermal growth factor receptor expression (P = .002), and HPV status (P = .02). The percentage of CD8 cells was significantly higher (P = .04) and the CD4:CD8 ratio was significantly lower (P = .02) in HPV-16-positive patients. A higher percentage of CD8 cells was associated with response to induction chemotherapy (P = .02) and complete tumor response after chemoradiotherapy (P = .045).

CONCLUSION

these findings confirm previous correlations of outcome with circulating CD8 cell levels and support the conjecture that improved adaptive immunity may play a role in the favorable prognosis of patients with HPV-16-positive cancers.

Podocyte depletion and glomerulosclerosis have a direct relationship in the PAN-treated rat

BACKGROUND

Podocytes are highly differentiated glomerular epithelial cells with limited potential to divide. They are responsible for maintaining and supporting the glomerular basement membrane so as to facilitate efficient filtration. The hypothesis tested was whether the development of glomerulosclerosis in the puromycin aminonucleoside (PAN)-treated rat could be attributed to podocyte depletion.

METHODS

PAN was injected in Sprague-Dawley rats once, twice, or three times at 30-day intervals. Podocytes were counted in glomeruli using immunoperoxidase histochemistry and antibodies to both GLEPP1 (PTPRO) and WT-1. Podocytes were assayed in urine using reverse transcription-quantitative polymerase chain reaction (RT-QPCR). Glomerular areas were measured by computerized morphometry.

RESULTS

In a preliminary experiment, a single injection of PAN caused a reduction in the glomerular podocyte count by 25%. Additional independent confirmation that podocytes were lost from glomeruli after PAN injection was obtained identifying detached podocytes in Bowman's space, measurement of nephrin and GLEPP1 mRNAs in urine, ultrastructural analysis of glomeruli, and identification of TUNEL-positive apoptotic podocytes in glomeruli. In a second experiment, sequential podocyte depletion by 15, 31, and 53% was achieved by the administration of one, two, or three injections of PAN at 30-day intervals. The region of the glomerulus devoid of podocytes developed glomerulosclerosis, and this area progressively increased as podocytes were progressively depleted. The correlation coefficient (r(2)) value for the relationship between percent podocyte depletion and glomerulosclerotic area was 0.99. The Y intercept of this plot showed that glomerulosclerosis was initiated when only 10 to 20% of podocytes were lost.

CONCLUSION

This report supports the growing body of data linking glomerulosclerosis directly to a reduction in relative podocyte number [increased glomerular area per podocyte (GAPP)]. It raises important questions related to the mechanisms of podocyte loss, strategies for prevention of podocyte depletion, and the prevention of progression of glomerular diseases.

Haploinsufficiency of CBFA2 causes familial thrombocytopenia with propensity to develop acute myelogenous leukaemia

Familial platelet disorder with predisposition to acute myelogenous leukaemia (FPD/AML, MIM 601399) is an autosomal dominant disorder characterized by qualitative and quantitative platelet defects, and propensity to develop acute myelogenous leukaemia (AML). Informative recombination events in 6 FPD/AML pedigrees with evidence of linkage to markers on chromosome 21q identified an 880-kb interval containing the disease gene. Mutational analysis of regional candidate genes showed nonsense mutations or intragenic deletion of one allele of the haematopoietic transcription factor CBFA2 (formerly AML1) that co-segregated with the disease in four FPD/AML pedigrees. We identified heterozygous CBFA2 missense mutations that co-segregated with the disease in the remaining two FPD/AML pedigrees at phylogenetically conserved amino acids R166 and R201, respectively. Analysis of bone marrow or peripheral blood cells from affected FPD/AML individuals showed a decrement in megakaryocyte colony formation, demonstrating that CBFA2 dosage affects megakaryopoiesis. Our findings support a model for FPD/AML in which haploinsufficiency of CBFA2 causes an autosomal dominant congenital platelet defect and predisposes to the acquisition of additional mutations that cause leukaemia.

Identification of a novel Ran binding protein 2 related gene (RANBP2L1) and detection of a gene cluster on human chromosome 2q11-q12

The giant 358-kDa protein Ran binding protein 2 (RanBP2/Nup358) is localized at the cytoplasmic side of the nuclear pore complex and likely constitutes the Ran-GTP binding site at the cytoplasmic face of the complex. RanBP2/Nup358 furthermore acts as a chaperone for red/green opsin molecules. Here, we report on the physical mapping of human RanBP2 between markers D2S340 and D2S1893. A duplication of the 5'-end sequence of RanBP2 occurs within 3 Mb distal to RanBP2. Detailed sequence analysis resulted in primers specific for this distal duplication. Polymerase chain reaction-based screening of cDNA libraries indicates that this transcript, called RanBP2alpha (HGMW-approved symbol RANBP2L1), is expressed in several tissues. Screening of a fetal brain cDNA library yielded a 4057-bp partial cDNA clone for RanBP2alpha. Its 5'-end is almost identical to RanBP2, whereas its 3'-part is distinct from RanBP2. Northern blot analysis using a probe of the 3'-untranslated sequence of RanBP2alpha detected in several tissues an 8-kb transcript representing the full length of the transcript. In pancreas and placenta, an additional transcript of 14 kb was detected. PAC clones containing the bona fide RanBP2 sequences were localized to 2q11-q12 by FISH analysis, and a region of high similarity was detected on 2p11-p12. In summary, we have identified a RanBP2 gene cluster on 2q11-q12 together with a novel gene termed RanBP2alpha, with high sequence similarity to RanBP2.

Isolation and characterization of cDNA clones for human apolipoprotein A-I

We have isolated cDNA clones encoding human apolipoprotein (apo) A-I. Twenty putative apo A-I cDNA clones were selected by screening 10,000 clones of an adult human liver cDNA library with an oligonucleotide probe. The probe was a mixture of synthetic 14-base-long DNA oligomers constructed to correspond to the codons for apo A-I amino acids 105-109. Four of these clones were examined further and showed 600- to 800-base-pair (bp) inserts. Preliminary restriction mapping and partial DNA sequence analysis indicated that the shorter inserts were a subset of the longer DNA inserts. DNA sequence analysis of the clone with an insert of approximately equal to 600 bp, designated pAI-113, revealed that it contained a DNA sequence corresponding to apo A-I amino acids 94-243. The DNA base sequence of this clone also contained a standard termination codon, polyadenylylation signal, and poly(A) tail. Partial DNA sequence of a second clone that contained an 800-bp insert, designated pAI-107, showed that it corresponded to apo A-I amino acids 18-243 and also included the 3' untranslated region. Isolation of these cDNA clones will facilitate molecular analyses of apolipoproteins in normal and disease states.

DNA sequence of baboon highly repeated DNA: evidence for evolution by nonrandom unequal crossovers

A highly repeated DNA was isolated from the West African baboon (Papio papio) as a 343-base-pair fragment after digestion of total baboon DNA with the restriction endonuclease BamHI. The DNA sequence of this fragment was obtained by chemical cleavage methods and is compared with the DNA sequence of related highly repeated primate DNAs from African green monkey (Cercopithecus aethiops) and man. The 343-base-pair baboon repeat consists of two related but nonidentical wings of 172 and 171 base pairs, respectively. The baboon 172-base-pair wing shares more homology with the African green monkey 172-base-pair repeat than with the baboon 171-base-pair wing. Comparison with the previously published monkey and human DNA sequences indicates that: (i) All the DNA sequences apparently arose from a common ancestral sequence. (ii) Evolution of the primate DNA sequences can be explained by a model involving unequal crossovers at specific points within the repeated DNA, possibly mediated by the sequence 5'-AAGG-3' 3'-TTCC-5' or its invert 5'-GGAA-3' 3'-CCTT-5'. (iii) There are alternating domains of conserved and divergent DNA sequences within each greater than 170-base-pair wing sequence. Taken together, the DNA sequences of these primates suggest a model whereby highly repeated DNAs are established and evolve as a consequence of unequal nonrandom exchanges of DNA duplexes. These exchanges may be mediated by short repeated nucleotide sequences and involve exchanges within and between the greater than 170-base-pair wings.

An autosomal dominantly inherited syndrome of facial asymmetry, esotropia, amblyopia, and submucous cleft palate (Bencze syndrome)

This is the second report of a dominantly inherited syndrome of facial asymmetry, esotropia, and amblyopia (Bencze syndrome). The phenotypic spectrum is expanded to include submucous cleft palate. The observation for the first time of male-to-male transmission seems to confirm an autosomal dominant mode of inheritance. The facial asymmetry in this family was mild and did not require surgical intervention. With the exception of one patient who had other abnormalities, intelligence was normal.