Trends in the use of radiation therapy for stage IIA prostate cancer from 2004 to 2013: a retrospective analysis using the National Cancer Database.

BACKGROUND: Recent studies have shown a decrease in the overall use of radiation therapy in the treatment of prostate cancer over the past several decades, as well as a more conservative overall treatment approach. We aim to determine whether this trend continued from 2004 to 2013, and to determine whether there were changes in utilization for various types of radiation. METHODS: We conducted this retrospective study using the National Cancer Database. We identified 706 877 patients with sufficient treatment information diagnosed with stage IIA prostate cancer between 2004 and 2013. Logistic regression models were used to evaluate the yearly trend in radiation therapy utilization. RESULTS: There was a significant decline in the use of radiation therapy from 2004 to 2013, from 54.4% in 2004 to 34.5% in 2013 compared with all the other treatments. The use of external beam radiation therapy (EBRT) declined from 27.1% in 2004 to 25.0% in 2013, brachytherapy declined from 19.7% in 2004 to 6.1% in 2013, and combination therapy declined from 6.8% in 2004 to 2.6% in 2013. However, when considering only patients receiving radiation treatments, the use of EBRT steadily increased from 50.6% in 2004 to 74.0% in 2013, whereas the use of brachytherapy declined from 36.7% in 2004 to 18.2% in 2013. Finally, although the proportion of patients receiving combination radiation therapy initially declined from 2004 to 2009 (from 12.7 to 8.3%), there was little change in utilization from 2009 to 2013 (8.3 to 8.5%). CONCLUSIONS: There has been a significant decline in the use of overall radiation therapy, as well as for each radiotherapy modality, for the treatment of prostate cancer since 2004. For patients that are receiving radiation, the use of EBRT has increased while brachytherapy use has decreased. These data serve to encourage further analysis as to the causes of these trends and how they affect patient care.

Characterization of antibody responses elicited by human immunodeficiency virus type 1 primary isolate trimeric and monomeric envelope glycoproteins in selected adjuvants.

We previously reported that soluble, stable YU2 gp140 trimeric human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein immunogens could elicit improved breadth of neutralization against HIV-1 isolates compared to monomeric YU2 gp120 proteins. In this guinea pig immunization study, we sought to extend these data and determine if adjuvant could quantitatively or qualitatively alter the neutralizing response elicited by trimeric or monomeric immunogens. Consistent with our earlier studies, the YU2 gp140 immunogens elicited higher-titer neutralizing antibodies against homologous and heterologous isolates than those elicited by monomeric YU2 gp120. Additionally, the GlaxoSmithKline family of adjuvants AS01B, AS02A, and AS03 induced higher levels of neutralizing antibodies compared to emulsification of the same immunogens in Ribi adjuvant. Further analysis of vaccine sera indicated that homologous virus neutralization was not mediated by antibodies to the V3 loop, although V3 loop-directed neutralization could be detected for some heterologous isolates. In most gp120-inoculated animals, the homologous YU2 neutralization activity was inhibited by a peptide derived from the YU2 V1 loop, whereas the neutralizing activity elicited by YU2 gp140 trimers was much less sensitive to V1 peptide inhibition. Consistent with a less V1-focused antibody response, sera from the gp140-immunized animals more efficiently neutralized heterologous HIV-1 isolates, as determined by two distinct neutralization formats. Thus, there appear to be qualitative differences in the neutralizing antibody response elicited by YU2 gp140 compared to YU2 monomeric gp120. Further mapping analysis of more conserved regions of gp120/gp41 may be required to determine the neutralizing specificity elicited by the trimeric immunogens.

Pathological and immunological changes after challenge infection with Pasteurella multocida in naive and immunized calves.

Challenge infections of calves with Pasteurella multocida were established to characterize the local inflammatory response and determine the effect of previous exposure to live bacteria on the post-challenge immune response. Experimental infections were established by intratracheal inoculation of P. multocida in both naive calves and calves that had been previously vaccinated with two subcutaneous (s.c.) injections of live bacteria. Histological, immunohistological and cytokine expression studies were performed on bronchoalveolar lavage (BAL) samples, lung parenchymal tissues and lung lymph nodes (LN). In comparison to uninfected control animals in which no lung lesions were observed, a patchy to confluent bronchopneumonia was observed following infection of naive calves, characterized by abscess formation, haemorrhage, oedema and suppurative consolidation. Cellular analysis following infection of naive animals was characterized by an influx of neutrophils in the BAL, with macrophages and dendritic cells observed in the lesion perimeter. A significant increase in the number of CD8(+) blasts expressing MHC (major histocompatibility) II was also observed in the BAL of infected calves. Decreased expression of interleukin (IL)-1 beta and increased expression of IL-8 compared to naive unchallenged controls was apparent in lung LN. In comparison, a more limited pathology was observed in vaccinated animals post-challenge, indicating partial protection conferred by the s.c. immunization with live bacteria. Studies of vaccinated animals showed the presence of bronchial-associated lymphoid tissue (BALT) in the lung tissue and an increase in the number of B-cells and CD4(+) T-cells expressing MHCII in the lung LN after challenge. In contrast to primary infection, there was no significant influx of neutrophils in the BAL. Instead, a population of newly recruited monocytes/macrophages was observed. Increased IL-2 expression and decreased IL-8 expression was observed in the LN, while IL-1 beta expression was not detected. The reduced neutrophil and increase monocyte response in the vaccinated calves may be associated with significant changes in the gamma delta T lymphocyte population in the BAL.

PNPase autocontrols its expression by degrading a double-stranded structure in the pnp mRNA leader.

Polynucleotide phosphorylase synthesis is autocontrolled at a post-transcriptional level in an RNase III-dependent mechanism. RNase III cleaves a long stem-loop in the pnp leader, which triggers pnp mRNA instability, resulting in a decrease in the synthesis of polynucleotide phosphorylase. The staggered cleavage by RNase III removes the upper part of the stem-loop structure, creating a duplex with a short 3' extension. Mutations or high temperatures, which destabilize the cleaved stem-loop, decrease expression of pnp, while mutations that stabilize the stem increase expression. We propose that the dangling 3' end of the duplex created by RNase III constitutes a target for polynucleotide phosphorylase, which binds to and degrades the upstream half of this duplex, hence inducing pnp mRNA instability. Consistent with this interpretation, a pnp mRNA starting at the downstream RNase III processing site exhibits a very low level of expression, regardless of the presence of polynucleotide phosphorylase. Moreover, using an in vitro synthesized pnp leader transcript, it is shown that polynucleotide phosphorylase is able to digest the duplex formed after RNase III cleavage.

Increased expression of Escherichia coli polynucleotide phosphorylase at low temperatures is linked to a decrease in the efficiency of autocontrol.

Polynucleotide phosphorylase (PNPase) synthesis is translationally autocontrolled via an RNase III-dependent mechanism, which results in a tight correlation between protein level and messenger stability. In cells grown at 18 degrees C, the amount of PNPase is twice that found in cells grown at 30 degrees C. To investigate whether this effect was transcriptional or posttranscriptional, the expression of a set of pnp-lacZ transcriptional and translational fusions was analyzed in cells grown at different temperatures. In the absence of PNPase, there was no increase in pnp-lacZ expression, indicating that the increase in pnp expression occurs at a posttranscriptional level. Other experiments clearly show that increased pnp expression at low temperature is only observed under conditions in which the autocontrol mechanism of PNPase is functional. At low temperature, the destabilizing effect of PNPase on its own mRNA is less efficient, leading to a decrease in repression and an increase in the expression level.

Interleukin-16 stimulates the expression and production of pro-inflammatory cytokines by human monocytes.

Interleukin-16 (IL-16) acts as a chemoattractant for CD4+ cells, as a modulator of T-cell activation, and plays a key role in asthma. This report describes the cytokine-inducing effects of IL-16 on total peripheral blood mononuclear cells (PBMC) and PBMC subpopulations. While CD4+ T lymphocytes did not secrete cytokines in response to rhIL-16, CD14+ CD4+ monocytes and maturing macrophages secrete IL-1beta, IL-6, IL-15 and tumour necrosis factor-alpha (TNF-alpha) upon rhIL-16 stimulation. The mRNA species for these four cytokines were detected as early as 4 hr post-stimulation, with protein being secreted by 24 hr. Secretion of IL-1beta and IL-6 by total PBMC was dose dependent, with maximal secretion being observed using 50 ng/ml rhIL-16. However, for IL-15 or TNF-alpha maximal secretion by total PBMC occurred with all concentrations between 5 ng/ml to 500 ng/ml rhIL-16. Purified monocytes/macrophages secreted maximal concentrations of all four cytokines in the presence of 500 ng/ml rhIL-16, except for monocytes where maximal secretion of IL-15 was, interestingly, observed with only 50 ng/ml rhIL-16. The use of higher concentrations of rhIL-16 (1000 ng/ml) inhibited secretion of all four cytokines. While these IL-16-induced cytokines are likely to be involved in the immune system's response to antigen, the data suggest that IL-16 may play a key role in initiating and/or sustaining an inflammatory response.

Cutting edge: CD4 is not required for the functional activity of IL-16.

IL-16 functions as a chemoattractant factor, inhibitor of HIV replication, and inducer of proinflammatory cytokine production. Previous studies have suggested that CD4 is the receptor for IL-16, because only CD4+ cells respond to IL-16 and both the anti-CD4 Ab OKT4 and soluble CD4 can block IL-16 function. However, these are only indirect evidence of a requirement for CD4, and to date a direct interaction between IL-16 and CD4 has not been shown. In this paper, we report that cells from CD4 knockout mice are as responsive to IL-16 as their CD4 wild-type equivalents in both assays testing for IL-16 function (chemotaxis and production of proinflammatory cytokines). In addition, the inhibitory effect of soluble CD4 on IL-16 function observed using CD4 wild type murine cells was not observed using CD4 knockout cells. These data demonstrate that CD4 is not required for IL-16 function and suggest that another molecule acts as the major receptor.

Endoribonuclease RegB from bacteriophage T4 is necessary for the degradation of early but not middle or late mRNAs.

The RegB endoribonuclease from bacteriophage T4 cleaves early mRNAs specifically in the middle of the sequence GGAG. We show here that RegB is required for the degradation of bulk T4 early mRNA. In the absence of RegB, the chemical half-life of early transcripts is increased nearly fourfold, whereas their functional half-life is increased twofold. RegB also regulates the translation of several prereplicative genes. The synthesis of several early proteins is down-regulated, probably as a consequence of RegB cleavages in the Shine-Dalgarno sequence of these genes. The synthesis of several other proteins is up-regulated, suggesting that processing by RegB might improve translation by changing the conformation of a transcript. In contrast, RegB does not affect the average half-life of middle and late mRNA. An analysis of the susceptibility to RegB of many GGAG motifs carried by these mRNA species showed that most middle and all late GGAG-carrying mRNAs escape RegB processing in spite of the fact that the enzyme is acting at least until ten minutes post-infection. The sensitivity or resistance to RegB observed during phage infection could be reproduced in uninfected Escherichia coli cells and in vitro. This shows that the GGAG-carrying RNAs that are uncut during T4 infection are not substrates, whatever the period of the T4 cycle when the transcripts are made.

Identification in a pseudoknot of a U.G motif essential for the regulation of the expression of ribosomal protein S15.

The ribosomal protein S15 from Escherichia coli binds to a pseudoknot in its own messenger. This interaction is an essential step in the mechanism of S15 translational autoregulation. In a previous study, a recognition determinant for S15 autoregulation, involving a U.G wobble pair, was located in the center of stem I of the pseudoknot. In this study, an extensive mutagenesis analysis has been conducted in and around this U.G pair by comparing the effects of these mutations on the expression level of S15. The results show that the U.G wobble pair cannot be substituted by A.G, C.A, A.C, G.U, or C.G without loss of the autocontrol. In addition, the base pair C.G, adjacent to the 5' side of U, cannot be flipped or changed to another complementary base pair without also inducing derepression of translation. A unique motif, made of only two adjacent base pairs, U.G/C.G, is essential for S15 autoregulation and is presumably involved in direct recognition by the S15 protein.

Characterization of cytokine profiles and double-positive lymphocyte subpopulations in normal bovine lungs.

OBJECTIVE: To characterize cytokine profiles and lymphocyte subpopulations in lung parenchyma and bronchoalveolar lavage (BAL) fluid from normal bovine lungs. ANIMALS: Eight 12- to 18-month-old cattle. PROCEDURE: Cell populations in BAL fluid and collagenase-digested lung parenchyma were analyzed by flow cytometry and monoclonal antibodies. Proportions of total cell populations were determined, using Giemsa-stained cytospots. Distribution of lymphocytes within the lung parenchyma was analyzed by immunohistochemistry, and cytokine mRNA species in the parenchyma were characterized by use of reverse transcriptase-polymerase chain reaction analysis. RESULTS: Cytokine profiles indicated high amounts of mRNA for interleukins 6 and 10 and transforming growth factor beta. In the BAL fluid and lung parenchyma, macrophages were the predominant cell type, although the proportion was lower in the parenchyma. Lymphocytes made up approximately 3% of both cell populations. Common to both lung compartments was the predominance of CD2+ and gamma delta T cells over B lymphocytes. There were more CD8+ T cells than CD4+ T cells in both compartments. The gamma delta cells made up approximately 9% of the lymphocyte populations. Two-color flow cytometry revealed CD8+ gamma delta T cell and CD8+CD5- populations that were unique to BAL fluid. In the BAL fluid and parenchyma, most CD4+ and CD8+ T cells expressed high amounts of CD44, a characteristic of memory T cells. The gamma delta T cells were CD44(10), as were B cells in the lung parenchyma. The B cells from BAL fluid expressed high amounts of CD44. Immunohistologic analysis of lung tissue revealed bronchus-associated lymphoid tissue structures with distinctive germinal center organization of B cells encompassed by CD4+ T cells. CONCLUSIONS: Results provided normal values for comparison with those of other species and with the bovine respiratory tract response to disease.

Restricted B-cell responses to microbial challenge of the respiratory tract.

The local B-cell response in the respiratory tract to infectious challenge has been analyzed in pigs and calves using two techniques: flow cytometry and antibody secreting cell (ASC) probes. Pneumonia in pigs caused by experimental infection with Mycoplasma hyopneumoniae resulted in a 25-fold increase in the B-cell population in BAL and lung parenchyma 28 days post infection. ASC probes revealed that the B-cell response of immune pigs to a large challenge infection was localized to lung parenchyma and tracheobronchal lymph nodes. Naive calves infected with Pasteurella multocida had a 5-fold increase in the B-cell blast population in lung parenchyma and BAL, and a greater than 60-fold increase in the draining lymph node at 9 days post infection. The ASC probes prepared post challenge from immune calves showed the response to be localized to the draining lymph nodes, with little response in lung parenchyma. A major finding was that ASC probes prepared from lung parenchyma and from pulmonary lymph nodes of both calves and pigs recognized a restricted range of bacterial antigens, particularly compared to the range of antigens recognized by concurrently circulating sera. The use of ASC probes demonstrates that there is a restricted B-cell repertoire in the respiratory tract.

The role of the AUU initiation codon in the negative feedback regulation of the gene for translation initiation factor IF3 in Escherichia coli.

The expression of the infC gene encoding translation initiation factor IF3 is negatively autoregulated at the level of translation, i.e. the expression of the gene is derepressed in a mutant infC background where the IF3 activity is lower than that of the wild type. The special initiation codon of infC, AUU, has previously been shown to be essential for derepression in vivo. In the present work, we provide evidence that the AUU initiation codon causes derepression by itself, because if the initiation codon of the thrS gene, encoding threonyl-tRNA synthetase, is changed from AUG to AUU, its expression is also derepressed in an infC mutant background. The same result was obtained with the rpsO gene encoding ribosomal protein S15. We also show that derepression of infC, thrS, and rpsO is obtained with other 'abnormal' initiation codons such as AUA, AUC, and CUG which initiate with the same low efficiency as AUU, and also with ACG which initiates with an even lower efficiency. Under conditions of IF3 excess, the expression of infC is repressed in the presence of the AUU or other 'abnormal' initiation codons. Under the same conditions and with the same set of 'abnormal' initiation codons, the repression of thrS and rpsO expression is weaker. This result suggests that the infC message has specific features that render its expression particularly sensitive to excess of IF3. We also studied another peculiarity of the infC message, namely the role of a GC-rich sequence located immediately downstream of the initiation codon and conserved through evolution. This sequence was proposed to interact with a conserved region in 16S RNA and enhance translation initiation. Unexpectedly, mutating this GC-rich sequence increases infC expression, indicating that this sequence has no enhancing role. Chemical and enzymatic probing of infC RNA synthesized in vitro indicates that this GC-rich sequence might pair with another region of the mRNA. On the basis of our in vivo results we propose, as suspected from earlier in vitro results, that IF3 regulates the expression of its own gene by using its ability to differentiate between 'normal' and 'abnormal' initiation codons.