Comparison of TNM staging systems for nasopharyngeal carcinoma, and proposal of a new staging system

BACKGROUND

There are few systematic evaluations regarding the sixth and seventh editions of the UICC/AJCC TNM Staging System (TNM6th, TNM7th) and Chinese 2008 Staging System (TNMc2008) for nasopharyngeal carcinoma (NPC).

METHODS

We classified 2333 patients into intensity-modulated radiotherapy (IMRT) cohort (n=941) and conventional radiotherapy (CRT) cohort (n=1392). Tumour staging defined by TNM6th, TNM7th and TNMc2008 was compared based on Akaike information criterion (AIC) and Harrell's concordance index (c-index).

RESULTS

For T-classification, TNM6th (AIC=2585.367; c-index=0.6390385) had superior prognostic value to TNM7th (AIC=2593.242; c-index=0.6226889) and TNMc2008 (AIC=2593.998; c-index=0.6237146) in the IMRT cohort, whereas TNMc2008 was superior (AIC=5999.054; c-index=0.623547) in the CRT cohort. For N-classification, TNMc2008 had the highest prognostic value in both cohorts (AIC=2577.726, c-index=0.6297874; AIC=5956.339, c-index=0.6533576). Similar results were obtained when patients were stratified by chemotherapy types, age and gender. Using staging models in the IMRT cohort, we failed to identify better stage migrations than TNM6th T-classification and TNMc2008 N-classification. We therefore proposed to combine these categories; resultantly, stage groups of the proposed staging system showed superior prognostic value over TNM6th, TNM7th and TNMc2008.

CONCLUSION

TNM6th T-classification and TNMc2008 N-classification have superior prognostic value in the IMRT era. By combining them with slight modifications, TNM criteria can be unified and its prognostic value be improved.

Prognostic impact of family history in southern Chinese patients with undifferentiated nasopharyngeal carcinoma

Background:

Family history of cancer is associated with developing nasopharyngeal carcinoma (NPC); however, the impact of it on survival among established NPC patients remains unknown.

Methods:

We retrospectively analysed 1773 southern Chinese patients. Associations between a first-degree family history of NPC and overall survival (OS), locoregional relapse-free survival (LRFS) and distant metastasis-free survival (DMFS) were estimated by Cox regression.

Results:

Among 1773 patients, 207 (11.7%) reported a first-degree family history of NPC. Compared with patients without a family history, the adjusted hazard ratios among those with it were 0.60 (95% confidence interval (CI), 0.37–0.98; P=0.040) for OS, 0.52 (95% CI, 0.24–1.12; P=0.096) for LRFS and 0.51 (95% CI, 0.27–0.97; P=0.040) for DMFS. There were trends for improving OS, LRFS and DMFS with increasing number of affected relatives (P_trend: 0.050, 0.114 and 0.044, respectively). But no significant benefits of family history in second- or third-degree relatives were observed. In subgroup analysis, we observed the effects of family history with restriction to male patients and those of advanced stage and treated with conventional radiotherapy and addition of chemotherapy.

Conclusion:

A first-degree family history of NPC is associated with improved survival of patients.

First Report of Curvularia Leaf Blight on Curcuma wenyujin Caused by Curvularia clavata in China

Curcuma wenyujin Y.H. Chen & C. Ling is a traditional Chinese medicinal herb in the Zingiberaceae family. Commonly known as Wen yujin, the root is widely used for alleviating pain and protecting the liver. A severe leaf blight disease was observed in three C. wenyujin farms in Hainan Province of China in October 2010. The obvious symptoms of leaf blight, yellow to brown irregular lesions (1 to 20 cm) on C. wenyujin, usually began at the tips of leaves and the main veins. This disease, especially severe from August to October, caused heavy damage and 100% of mature plants (10 months old) in farms were infected. The disease was most severe when continuous cropping was performed and showed slight improvement when rotation was adopted. Farmers usually sprayed carbendazim (50% WP) and thiophanate-methyl (70% WP) to control this disease, but these treatments were not effective. To isolate the causal pathogen, diseased plants were collected in October 2010 from a field of the Hainan Branch Institute of Medicinal Plant Development in Hainan Province. Lesion tissue was removed from the border between symptomatic and healthy tissue, surface sterilized in 75% ethanol for 1 min, washed in three changes of sterile distilled water, transferred to potato dextrose agar (PDA) plates, and incubated at 28°C for 7 days. Single spore cultures of five isolates were obtained and identified as Curvularia clavata based on morphological characteristics (1). Conidia measured 20 to 29 × 7.5 to 10.5 μm (n = 100), were curved, 3-septate, and the third cell from the base was larger and darker than the others. Mycelia of single spore cultures growing on PDA for 5 days were used for DNA extraction using a plant genomic DNA kit (TIANGEN, Beijing). The internal transcribed spacer (ITS) region of the rDNA was amplified using primers ITS1 and ITS4. The amplicons were 562 bp in length (GenBank Accession No. JQ730852) and had 99% nucleotide identity with the GenBank Accession No. JN021115 and AF071336 of C. clavata. Pathogenicity tests were conducted using fresh and healthy detached Curcuma wenyujin leaves. Mycelial discs (10 mm) removed from a 5-day-old colony on PDA were used for inoculation. Each isolate was inoculated on three distinct leaves (two distinct inoculations per leaf). Three additional leaves inoculated with sterile PDA discs were used as control. Inoculated leaves were covered with a polythene film to maintain high humidity. Leaves in trays were kept in a growth chamber at 28°C and observed for symptom appearance every day. Five days after inoculation, inoculated leaves developed blight symptoms similar to those observed on naturally infected leaves. No symptoms were observed on non-inoculated leaves. C. clavata was reisolated from the inoculated leaves, thus fulfilling Koch's postulates. C. clavata has been previously reported to be economically important on a number of other hosts (2). To our knowledge, this is the first report of Curvularia leaf blight on Curcuma wenyujin caused by C. clavata in China. References: (1) A. M Mandokhot et al. Eur. J. Plant Pathol.78:65, 1972. (2) T. Y. Zhang et al. Flora fungorum sinicorum: Beijing, China, 2010.

HMGB1 promotes the differentiation of Th17 via up-regulating TLR2 and IL-23 of CD14+ monocytes from patients with rheumatoid arthritis

High-mobility group box 1 (HMGB1) is a non-histone nuclear protein that is released extracellulary and has been implicated in autoimmune disease. Toll-like receptor 2 (TLR2) signalling is thought to be essential for the inflammatory response and for immune disorders. In recent studies, enhanced HMGB1 and TLR2 expressions have been found in rheumatoid arthritis (RA), respectively. The aim of this study is to explore whether HMGB1 stimulation can up-regulate the expression of TLR2 on CD14(+) monocytes from patients with RA and to clarify the subsequent events involving Th17 cells and Th17 cell-associated cytokine changes. Our results showed that the frequency of CD14(+) cells in peripheral blood mononuclear cell (PBMC) was obviously increased, and enhanced expression of TLR2 on CD14(+) monocytes was also found in patients with RA, compared with healthy controls with statistical significance (P < 0.001). In addition, the levels of IL-17, IL-23 and IL-6 in supernatants from cultured monocytes from patients and in patient's plasma were increased, and NF-κB, the downstream target of TLR2, also showed a marked elevation after monocytes were stimulated by HMGB1. This implies that the enhanced TLR2 pathway and Th17 cell polarization may be due to HMGB1 stimulation in rheumatoid arthritis.

Expression of the transformed phenotype induced by diverse acting viral oncogenes mediates sensitivity to growth suppression induced by caffeic Acid phenethyl ester (cape)

Caffeic acid phenethyl ester (CAPE) displays enhanced growth suppressive and toxic effects toward cloned rat embryo fibroblast (CREF) cells transformed by adenovirus type 5 (Ad5) or the Ad5 E1A transforming gene versus untransformed CREF cells (Su et al, Mol Carcinogen 4: 231-242, 1991). The present study was conducted to determine if transformation of CREF cells with additional oncogenes rendered these cells sensitive to the antiproliferative effect of CAPE. Additionally, studies were conducted to determine if reversion of the transformed phenotype could modify CAPE sensitivity. CAPE displayed increased growth suppressive activity toward CREF cells transformed by a number of oncogenes, including Ha-ras, v-src, v-raf, human papillomavirus type 18 (HPV-18) and human papillomavirus type 51 (HPV-51). Employing Ha-ras-transformed CREF (Ha-ras) and Ha-ras-transformed CREF cells overexpressing the Krev-1 suppressor gene (Ha-ras/Krev-1), evidence for a direct relationship between expression of the transformed phenotype and CAPE sensitivity was demonstrated. Ha-ras/Krev-1 cells displaying a suppression of the transformed phenotype exhibited increased resistance to CAPE-induced growth suppression versus Ha-ras cells, whereas Ha-ras/Krev-1 cells escaping transformation-suppression following in vivo growth in nude mice displayed enhanced sensitivity to growth-suppression induced by CAPE. Similarly, mutant Ad5 (H5hr1)-transformed and v-src-transformed CREF cells displaying a stable reversion in transformation also displayed a reduced sensitivity to CAPE versus their transformed counterparts. These observations indicate a direct relationship between expression of the transformed phenotype and CAPE sensitivity. Elucidation of the mechanism by which CAPE selectively inhibits growth of transformed cells should provide important insights into the critical molecular changes mediating expression of the transformed state and could help identify cellular targets for cancer therapy.

Transcriptional switching model for the regulation of tumorigenesis and metastasis by the ha-ras oncogene - transcriptional changes in the ha-ras tumor-suppressor gene lysyl oxidase

A model system is described that allows an analysis of the molecular and biochemical changes associated with expression and suppression of the oncogenic and metastatic phenotype of cloned rat embryo fibroblast (CREF) cells. Ha-ras-transformed CREF cells are morphologically transformed, anchorage-independent and both tumorigenic and metastatic in athymic nude mice and syngeneic Fischer rats. Co-expression of the Ha-ras oncogene and Krev-1 tumor suppressor gene in CREF cells results in suppression of in vitro transformation. In contrast, Ha-ras/Krev-1 transformed CREF cells retain, with greatly extended latency periods, both tumorigenic and metastatic capabilities in athymic nude mice. The present study investigates changes in the Ha-ms suppressor gene, rrg (lysyl oxidase), during expression and suppression of the oncogenic phenotype in CREF cells. Nontumorigenic CREF cells and CREF cells transformed by the Ha-ras and Krev-1 gene that express a suppression in in vitro transformation contain elevated levels of lysyl oxidase mRNA and protein. In contrast, Ha-ms and Ha-ras/Krev-1 nude mouse tumor- and nude mouse lung metastasis-derived CREF cells contain reduced levels of lysyl oxidase mRNA and protein. Nuclear run-on assays indicate that suppression of lysyl oxidase expression in transformed subclones of CREF cells correlates with a reduction in transcription of the lysyl oxidase gene. Taken together, the current studies support a transcriptional switching model in which lysyl oxidase expression correlates directly with suppression of the Ka-ms-induced transformation phenotype and escape from oncogenic suppression correlates with a transcriptional silencing of the lysyl oxidase gene and decreased lysyl oxidase mRNA and protein.

Caffeic acid phenethyl ester profoundly modifies protein synthesis profile in type 5 adenovirus-transformed cloned rat embryo fibroblast cells

Caffeic acid phenethyl ester (CAPE), an active component of propolis from bee hives, exerts a plethora of biological changes in diverse systems. These include antimitogenic, anticarcinogenic, anti-inflammatory and immunomodulatory responses. CAPE directly induces programmed cell death (apoptosis) in type 5 adenovirus (Ad5)-transformed cloned rat embryo fibroblast cells, wt3A. To identify the gene and protein expression changes induced by CAPE in wt3A cells we used a strategy involving in vitro translation of mRNAs followed by high resolution two-dimensional (2D) gel electrophoresis. This approach results in the detection of 745 spots, including 172 displaying differences in expression upon exposure to CAPE. A high proportion of spots show profound changes in spot intensity (42 spots with increased and 27 spots with decreased intensity) following CAPE treatment. These studies provide a basis for comparing these changes to known protein patterns of various cell populations with an ultimate aim of identifying families of polypeptides responsible for the up- and down-regulation of cellular proteins during CAPE-induced apoptosis. Specific newly appearing or completely disappearing spots (52 and 51 molecular species, respectively) will be used to attempt to identify and retrieve their cDNA counterparts from an ordered cDNA library. These approaches represent a novel strategy for cloning genes associated with and potentially mediating apoptosis.

Direct Response to Proton Beam Linear Energy Transfer (LET) in a Novel Polymer Gel Dosimeter Formulation

Linear energy transfer (LET) of clinical proton beams is an important parameter influencing the biological effects of radiation. This work demonstrates LET-induced response enhancement in novel formulations of polymer gel dosimeters, potentially useful for LET mapping of clinical proton beams. A series of four polymer gel dosimeters (labeled A through D), prepared based on the BANG3-Pro2 formulation, but with varying concentrations of polymerization modifiers, were irradiated by a clinical proton beam with a spread out Bragg peak modulation (SOBP) and read out using the OCTOPUS-IQ optical CT scanner. The evaluation of optical density profiles in the SOBP (constant physical dose) revealed response deviations at the distal end consistent with variations in gel composition. Maximum response deviations were as follows: −3% (under-response) for gel A, and over-response of 2%, 12%, and 17% for gels B, C, and D, respectively, relative to the mean dose in the center of the SOBP. This enhancement in optical response was correlated to LET by analytical calculations. Gels A and B showed no measurable dependence on LET. Gel C responded linearly in the limited range from 1.5 to 3.5 keV/μm. LET response of gel D was linear up to at least 5.5 keV/μm, with the threshold at about 1.3 keV/μm. These results suggest that it may be possible to develop a polymer gel system with direct optical response to LET for mapping of LET distributions for particle therapy beams.

Increased T-cell stimulating activity by mutated SEC2 correlates with its improved antitumour potency

AIMS

To investigate the improved antitumour activity of SAM-3 compared with recombinant staphylococcal enterotoxins C2 (rSEC2).

METHODS AND RESULTS

Methylthiazol tetrazolium and flow cytometry assays showed that the antitumour activity of SAM-3 in vivo was improved because of enhanced T-cell stimulating potency, resulting in massive activation of T cells, particularly CD4(+) and CD8(+) T cells, and subsequent cytokine release. Quantitative real-time PCR assay showed that despite similar Vβ specificities induced by rSEC2 and SAM-3, the quantities of activated T cells bearing specific Vβin vitro were different.

CONCLUSIONS

The results strongly suggested that the increased SAM-3-T-cell receptor (TCR) binding affinity contributed to massive T-cell activation and cytokine release, substantially amplifying antitumour immune response in vivo.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provided evidence for the mechanism of SAM-3 antitumour activity improvement compared with rSEC2. Results indicated that SAM-3 could be used as a potent powerful candidate agent for tumour treatment in clinics.