Clinical and demographic characteristics predictive of treatment outcomes for certolizumab pegol in moderate to severe Crohn's disease: analyses from the 7-year PRECiSE 3 study

BACKGROUND

Clinical factors were previously identified as predictors of short-term treatment efficacy in Crohn's disease (CD). The PRECiSE 3 (P3) 7-year trial provides an opportunity to study predictors of short- and long-term clinical remission among CD patients treated with certolizumab pegol (CZP).

AIM

To identify factors that influence long-term remission of CD with CZP treatment.

METHODS

Patients who had completed placebo-controlled studies (PRECiSE 1/PRECiSE 2, P1/P2) enrolled in P3 and received open-label CZP 400 mg every 4 weeks up to 7 years. Baseline predictors included, but were not limited to, smoking status, disease duration, prior inflammatory bowel disease (IBD) surgery, Harvey-Bradshaw Index (HBI), albumin, haematocrit and CZP exposure; association with time to initial remission (HBI ≤4) was tested for patients who received CZP in P1/P2; time to loss of remission/frequency of maintenance of remission was also tested. Univariate analyses and multivariate Cox or logistic regression models were used.

RESULTS

Predictors for initial remission (N = 377) included age, haematocrit, prior IBD surgery and entry HBI (P < 0.05 for all). Predictors for loss of remission (N = 437) included HBI, serum albumin concentration, haematocrit, smoking status and exposure. Predictors of maintenance of remission (N = 437) included haematocrit, IBD surgery, HBI, disease duration, serum albumin concentration and exposure. Significant predictors were confirmed with stepwise multivariate regression models.

CONCLUSIONS

These analyses identified several influential parameters for short-and long-term remission of Crohn's disease with certolizumab pegol treatment. The data yield valuable hypotheses regarding factors that influence certolizumab pegol treatment. More investigation is needed. (ClinicalTrials.gov identifier NCT00552058).

Clinical outcomes in Asian elderly kidney transplant recipients: a multicenter cohort study

BACKGROUND

The kidney transplantation rate in elderly patients is increasing rapidly. However, the clinical outcomes of kidney transplantation in elderly patients have not yet been thoroughly evaluated.

METHODS

This multicenter cohort study included adult kidney transplant recipients (KTRs) admitted to five major tertiary hospitals in Korea between 1997 and 2012. A total of 3,565 adult participants were enrolled. Patient survival, allograft survival, and biopsy-proven acute rejection (BPAR) of 242 elderly recipients (≥ 60 years) were assessed and compared with those of a younger population.

RESULTS

Patients were divided into five groups according to age at time of transplantation. The proportion of elderly patients was 6.7 % (mean age, 63.1 ± 2.7 years; n = 242). The numbers of male patients (69.4%), those with diabetes mellitus history (36.3%), and those with pretransplantation ischemic heart disease history (17.7%) were significantly higher in the elderly group than in the younger age groups. Elderly patients were more likely to receive a cadaveric kidney, and overall mortality rates were significantly higher in the elderly patients (1-year survival 93.3%, 5-year survival 91.3%). However, death-censored allograft survival rate and BPAR were not affected by patient age (P = .104 and .501, respectively). Among the elderly, BPAR and female donors were independent risk factors for allograft loss.

CONCLUSION

The overall survival rate of the elderly KTRs was significantly lower than that of younger KTRs. However, the death-censored allograft survival rate did not differ between groups. Kidney transplantation should not be stagnated especially in elderly patients with end-stage renal disease.

Robust MR assessment of cerebral blood volume and mean vessel size using SPION-enhanced ultrashort echo acquisition

Intravascular superparamagnetic iron oxide nanoparticles (SPION)-enhanced MR transverse relaxation rates (∆R2(⁎) and ∆R2) are widely used to investigate in vivo vascular parameters, such as the cerebral blood volume (CBV), microvascular volume (MVV), and mean vessel size index (mVSI, ∆R2(⁎)/∆R2). Although highly efficient, regional comparison of vascular parameters acquired using gradient-echo based ∆R2(⁎) is hampered by its high sensitivity to magnetic field perturbations arising from air-tissue interfaces and large vessels. To minimize such demerits, we took advantage of the dual contrast property of SPION and both theoretically and experimentally verified the direct benefit of replacing gradient-echo based ∆R2(⁎) measurement with ultra-short echo time (UTE)-based ∆R1 contrast to generate the robust CBV and mVSI maps. The UTE acquisition minimized the local measurement errors from susceptibility perturbations and enabled dose-independent CBV measurement using the vessel/tissue ∆R1 ratio, while independent spin-echo acquisition enabled simultaneous ∆R2 measurement and mVSI calculation of the cortex, cerebellum, and olfactory bulb, which are animal brain regions typified by significant susceptibility-associated measurement errors.

Effect of dietary supplementation of procyanidin on growth performance and immune response in pigs

This study was performed to determine the effect of dietary supplementation of procyanidin on growth performance, blood characteristics, and immune function in growing pigs. In experiment 1 (Exp. 1), thirty-two crossbred pigs with an initial BW of 19.2±0.3 kg were allocated into 4 treatments for an 8-wk experiment: i) CON (basal diet), ii) MOS 0.1 (basal diet+0.1% mannanoligosaccharide), iii) Pro-1 (basal diet+0.01% procyanidin), and iv) Pro-2 (basal diet+0.02% procyanidin). Pigs fed Pro-1 and Pro-2 diets had greater (p<0.05) gain:feed ratio compared with those fed CON or MOS 0.1 diets. Serum creatinine concentration was less (p<0.05) in Pro-2 treatment than those in CON, MOS 0.1 and Pro-1 treatments. In Exp. 2, twelve pigs (BW 13.4±1.3 kg) received basal diet with i) 0 (CON), ii) 0.02% (Pro-0.02%), and iii) 0.04% procyanidin (Pro-0.04%) for 4 wk. Concentration of platelets was lower (p<0.05) in the Pro-0.04% group compared to CON at 24 h after lipopolysaccharide (LPS) challenge. In addition, secretion of cytokines from cultured peripheral blood mononuclear cells (PBMC) in the presence or absence of procyanidin was examined. The levels of interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α were lower (p<0.05) in Pro (LPS-stimulated PBMCs+procyanidin) than those in CON (LPS-stimulated PBMCs+PBS) at 4 h after LPS challenge. These data suggest that dietary addition of procyanidin improves feed efficiency and anti-inflammatory cytokines of pigs.

Role of the superior turbinate when performing endoscopic endonasal transsphenoidal approach

BACKGROUND

This study examined the relationship between the superior turbinate and natural ostium of the sphenoid sinus, as seen during the endoscopic endonasal transsphenoidal approach (EETSA) for sellar lesions and described how to enter the sphenoethmoid cell safely for complete exposure of the sellar floor, including adjacent vital structures such as the prominence of the optic nerve and carotid artery.

MATERIALS AND METHODS

This study retrospectively reviewed the medical records and operative findings of 154 patients, who underwent EETSA between February 2009 and February 2011. We evaluated the location of the natural ostium of the sphenoid sinus relative to the superior turbinate and revealed the clinical significance of the superior turbinate as a surgical guide to enter into the sphenoethmoid cell during EETSA.

RESULTS

The natural ostium of the sphenoid sinus was located medially to the posteroinferior end of the superior turbinate in 151 (98%) patients. In 1 patient, the natural ostia of the sphenoid sinus were located lateral to the superior turbinate bilaterally. Sphenoethmoid cell was encountered in 53 (34%) patients. We could easily enter the sphenoethmoid cell at the point where the superior turbinate was attached to the anterior wall of the sphenoid sinus.

CONCLUSIONS

The superior turbinate is a good surgical landmark for identifying the natural ostium of the sphenoid sinus and as a guide for the surgical entrance to the sphenoethmoid cell extending to the sphenoid sinus during EETSA.

Costs of illness and quality of life in patients with systemic lupus erythematosus in South Korea

OBJECTIVE

To assess the costs of illness, health-related quality of life (HRQOL) and their associated factors in patients with systemic lupus erythematosus (SLE) in South Korea.

METHOD

Two hundred and one patients with SLE were enrolled at the Rheumatology clinic of Seoul National University Hospital. Direct, indirect and total costs and HRQOL were measured using hospital electronic data and face-to-face interview. Socio-demographic and clinical factors associated with cost of illness and HRQOL were analyzed using multiple regression and multivariate logistic regression.

RESULTS

The average total cost of illness was estimated to be KRW 9.82 million (US $ 8993) per year, of which 41.6% was accounted for by direct costs and 58.4% by indirect costs. In multivariate regression, patients with renal involvement and those with depression incurred an average increment in annual total costs of 37.6% (p = 0.050) and 49.1% (p = 0.024), respectively, and an average increment in annual direct costs of 26.4% (p = 0.050) and 43.3% (p = 0.002), respectively, compared with patients without renal involvement and depression, respectively. In addition, disease damage was positively associated with an average increment in annual total and direct costs (55.3%, p = 0.006; 33.3%, p = 0.013, respectively), and the occurrence of indirect costs (OR 2.21, 1.09-4.88). There was no significant difference in HRQOL between patients with and without renal involvement (0.655 vs. 0.693, p = 0.203) CONCLUSION: Renal involvement, depression, and disease damage were major factors associated with higher total and medical costs for patients with SLE in South Korea. Effective treatment of renal disorders and depression may reduce the high economic burden of SLE.

The optimal morning:evening ratio in total dose of twice-daily biphasic insulin analogue in poorly controlled Type 2 diabetes: a 24-week multi-centre prospective, randomized controlled, open-labelled clinical study

AIMS

Biphasic insulin analogues are widely used in patients with Type 2 diabetes mellitus suboptimally controlled on oral anti-diabetic drugs. Several topics in this area remain controversial, including how to divide the daily dose of biphasic insulin analogue. We aimed to determine the optimal dosing ratio of twice-daily biphasic insulin analogue and to compare the glycaemic efficacy among groups of patients using different initial dosing ratios of biphasic insulin analogue.

METHODS

A total of 100 poorly controlled insulin-naive subjects with Type 2 diabetes [HbA1c ≥ 58 mmol/mol, (7.5%)] on oral anti-diabetic drugs were randomized into three groups according to initial morning:evening dosing ratio (group I, 50:50; group II, 55:45; group III, 60:40) of twice-daily biphasic insulin analogue (biphasic insulin aspart 70/30, biphasic insulin aspart 30). The primary outcome measure was the difference in pre-breakfast to pre-dinner dose ratio at the end of the study.

RESULTS

Twice-daily biphasic insulin analogue showed a significant improvement in glycaemic control [HbA1c from 70 mmol/mol (8.6%) to 60 mmol/mol (7.6%)] after 24 weeks regardless of the initial dose ratio given. Despite the similar efficacy and safety profiles among three groups, morning dose was significantly increased (from 50:50 to 55:45-60:40) in group I after 24 weeks. However, there was no significant change in splitting ratio in groups II and III (with higher morning dose) over the 24-week treatment period.

CONCLUSIONS

These results indicate that initiating twice-daily biphasic insulin analogue on regimens with a higher dose before breakfast than before dinner (i.e. ratio approximately 55:45 to 60:40) might be more appropriate in Korean subjects with Type 2 diabetes.

Establishment of a reliable and reproducible murine osteoarthritis model

OBJECTIVE

Many osteoarthritis (OA) models have been developed in mice to understand OA progression and evaluate new OA therapies. However, the individual variation of the joint lesions remains a critical problem in most of the current OA models. We established an OA model in C57BL/6 mice that is more reproducible and amenable to therapeutic intervention by controlling their movement.

DESIGN

OA was induced in 9-week-old C57BL/6 mice by destabilizing the medial meniscus. The mice were then raised in the standard cage for free movement or in a confined cage customized to restrict movement. Mice in the confined cage were subjected to no exercise or exercise of 400, 800, and 1200 m/day.

RESULTS

OA lesions of mice in the confined cage were more severe in the exercise group and showed much less variation. However, the patterns of OA lesions over time were quite different depending on the amount of daily exercise; the patterns increased linearly until 8 weeks in 400 m/day exercise group, but showed plateauing after 4 weeks in 800 m/day and 1200 m/day groups. The validity of our novel OA model with movement control was proven by successfully discriminating the therapeutic effect of hyaluronic acid (HA) in histological scores, while the OA model using standard caging showed a statistically insignificant difference.

CONCLUSION

The mouse OA model using the confine cage and enforced periodic exercise of mice is more reproducible and reliable than standard caging methods.

Effects of single or combined dietary supplementation of β-glucan and kefir on growth performance, blood characteristics and meat quality in broilers

1. This study was conducted to evaluate the effects of dietary β-glucan and kefir (a fermented milk product) on growth performance, blood profiles, relative organ weight and meat quality in broilers. 2. A total of 375 day-of-hatch mixed sex ROSS 308 broilers (BW of 46 ± 0.1 g) were used in a 5-week experiment and randomly allotted to one of the following dietary treatments: (1) NC, basal diet; (2) PC, basal diet + 40 mg/kg of avilamycin; (3) B, NC + 0.1% β-glucan; (4) K, NC + 0.1% kefir; (5) BK, NC + 0.1% β-glucan + 0.1% kefir. 3. During weeks 0-3, broilers in B, K and BK treatments had higher body weight gain (BWG) than those in NC treatment. During weeks 4-5, BK treatment had a higher BWG than NC treatment. Overall, broilers given PC, K and BK diets had higher BWG than those given NC diet. The feed efficiency ratio (FCR) was improved by PC treatment. 4. Relative liver weight was increased by B treatment, whereas the relative weight of breast meat and gizzard was higher in BK group than that in NC group. Broilers given PC, B and BK diets had greater breast meat redness value and reduced drip loss at d 5 and d 7. The cooking loss was also reduced by B and BK treatments compared with NC treatment. 5. In conclusion, the results suggested that inclusion of 0.1% β-glucan and 0.1% kefir, either individually or combined, would improve growth performance and benefit meat quality in broiler chickens.

Comparison of polyvinyl alcohol coated nasal packing with non-absorbable nasal packing

BACKGROUND

A number of different nasal packing materials are available for prevention of nasal bleeding after endoscopic sinus surgery. Polyvinyl alcohol (PVA) coated nasal packing is an expandable packing for use in rhinological surgery. This innovative surf- ace treatment helps to reduce the possibility of adherence to tissue and of blood clotting within the sponge. The present study investigated the effects of PVA coated packing and non-absorbable packing with respect to pain, healing site and postoperative bleeding following endoscopic sinus surgery.

METHODOLOGY

Patients between 18-80 years of age undergoing sinus surgery were enrolled. Each patient`s ethmoid cavities were randomised to receive PVA coated packing material or the standard non-absorbable sinus packs. The remaining nasal packing material was removed on the 2nd day in the clinic. We determined visual analog scale score, bleeding time and wound healing status. A single rhinologist graded postoperative endoscopic appearance. Length of follow-up was 3 months.

RESULTS

Thirty three patients were recruited. There was a significant difference in the bleeding time between the two groups, but pain and wound healing were not significantly different between the two groups.

CONCLUSION

PVA-coated nasal packing presents comparable characteristics with traditional nasal packing.

Effects of lactulose supplementation on performance, blood profiles, excreta microbial shedding of Lactobacillus and Escherichia coli, relative organ weight and excreta noxious gas contents in broilers

This study was to evaluate the effects of lactulose supplementation on performance, blood profiles, excreta microbial shedding of Lactobacillus and Escherichia coli, relative organ weight and excreta noxious gas contents in broilers. A total of 720 ROSS 308 broilers with a body weight of 46 ± 0.1 g (1 day of age) were used in a 28-d experiment. Broilers were randomly allotted to 4 experiment diets with 12 replicate pens and 15 birds per pen. Dietary treatments were as follows: NC, negative control (without antibiotic); PC, NC + 0.1% tiamulin; L1, NC + 0.1% lactulose; and L2, NC + 0.2% lactulose. Broilers were fed with phase 1 (1-8 day), phase 2 (9-18 day) and phase 3 (19-28 day) diets in the form of mash. During day 1-8, broilers fed the PC and L2 diets had higher (p < 0.05) body weight gain than those fed the NC diet. During day 19-28, broilers fed the L1 and L2 diets had lower (p < 0.05) feed intake than those fed the NC diet. The feed conversion ratio (FCR) was decreased (p < 0.05) in L1 treatment compared with NC treatment. Overall, the FCR was improved (p < 0.05) in all supplementation treatments compared with NC treatment. The apparently metabolizable nitrogen in L1 treatment was higher (p < 0.05) than that in NC treatment at day 28. The excreta Lactobacillus was increased and E. coli was decreased in PC and L2 treatments compared with NC treatment at day 28 (p < 0.05). The excreta NH3, H2S and acetic acid contents were decreased (p < 0.05) in L1 and L2 treatments compared with NC treatment. The relative weight of abdominal fat of broilers fed the PC diet was lowest (p < 0.05) compared with other treatments. In conclusion, this study indicated that dietary supplementation of 0.1% or 0.2% lactulose could improve growth performance, decrease excreta E. coli and excreta NH3 and H2S contents.

Abstract P1-01-23: Increased Diagnostic Performance of Sentinel Lymph Node Biopsy Combined with Radiologic-pathologic Factors After Neoadjuvant Chemotherapy in Breast Cancer Patients with Cytologically Proven Node Metastasis at Diagnosis

Background: It is undetermined whether sentinel lymph node biopsy (SLNB) is feasible and accurate for predicting final nodal status after neoadjuvant chemotherapy (NCT) in breast cancer patients with cytologically proven node metastasis at the time of diagnosis, although currently completion node dissection is a standard surgical procedure for the management of axilla. The aim of this study was to investigate diagnostic performance of SLNB after NCT in this subgroup.

Methods: Of 374 patients with T1-T3 breast cancer who received NCT, 178 had initially biopsy proven axillary/supraclavicular metastasis and subsequently underwent SLNB using radioisotope alone followed by completion node dissection between 2008 and 2011. Detection rate, sensitivity, false negative rate (FNR), negative predictive value (NPV), and accuracy of SLNB were retrospectively analyzed and it was explored using regression analysis whether combination with clinicopathologic factors improved performance.

Results: At initial presentation, 60.7% of patients were cT2 stage and 88.2% treated with concurrent or sequential anthracycline plus taxane preoperatively. SLNB was successfully performed in 169 (94.9%) patients. The mean number of sentinel and regional nodes retrieved was 2.1 ± 1.6 and 12.8 ± 6.3, respectively. Tumoral non-responder and extensive residual nodal disease were significantly associated with detection failure of SLNB. Conversion to node-negative disease was noted in 69 (40.8%) patients. Sensitivity, FNR, NPV, and accuracy of SLNB were 78.0%, 22.0%, 75.8%, and 87.0%, respectively and diagnostic performance increased when ≥ 3 sentinel nodes were evaluated. By logistic regression model, tumoral and nodal responder, absent lymphovascular invasion (LVI), estrogen receptor (ER)-negativity, and HER2-positivity were significantly associated with node-negative disease after NCT. Area under the receiver operating characteristic curve increased from 0.890 to 0.949 when considering radiologic-pathologic factors and FNR was the lowest value of 14.3% in 46 patients with tumoral responder, absent LVI, and ER-negative tumor.

Conclusions: SLNB was technically feasible but solely showed higher FNR in this study. Improved diagnostic performance of SLNB combined with radiologic-pathologic characteristics suggests possible clinical value of SLNB after NCT in highly selected patients with node metastasis at diagnosis.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-01-23.

Abstract P2-05-03: Mouse double minute 2 nuclear expression as a prognostic marker in patients with breast cancer

BACKGROUND: Mouse double minute 2 (Mdm2) is a negative regulator of tumor suppressor, p53, thus Mdm2 expression may play a role in cancer development and prognosis, however, the definite role of Mdm2 in breast cancer is unclear. The aim of the study is to evaluate the correlation between Mdm2 expression and prognosis of breast cancer.

METHODS: Mdm2 expression was determined from immunohistochemistry of tissue microarrays of 865 patients with breast cancer who underwent surgery. Clinicopathologic characteristics and survival data were analyzed using a univariate and multivariate analysis. Mdm2 expression was categorized into 3 groups: negative; no Mdm2 expression in nucleus and cytoplasm, cytoplasm-positive; cytoplasmic expression of Mdm2, nucleus-positive; nuclear with or without cytoplastimc expression of Mdm2.

RESULTS: Negative, cytoplasm-positive, and nucleus-positive groups were observed in 59.2%, 10.9%, and 29.9% of patients, respectively. Nucleus-positive group was associated with young age, high grade, negativity of estrogen and progesterone receptor, HER2 positivity, and high Ki-67 index. With median 86.0 follow-up months, nucleus-positive group showed poorer disease-free survival and overall survival than negative and cytoplasm-positive groups. In multivariate analysis, cytoplsmic expression of Mdm2 was not significantly associated with survival, whereas nuclear expression of Mdm2 was related to poor prognosis. (HR, 1.44; 95% CI, 1.041–1.993 for DFS; HR, 1.546; 95% CI, 1.060–2.255 for OS)

CONCLUSIONS: Nuclear expression of Mdm2 was an independent prognostic factor in patients with breast cancer. Patterns of Mdm2 expression in tumor cell should be rendered in the evaluation of Mdm2 in breast cancer.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-05-03.

Elevated levels of preoperative CA 15-3 and CEA serum levels have independently poor prognostic significance in breast cancer

BACKGROUND

To evaluate the prognostic value of preoperative tumor markers, cancer antigen 15-3 (CA 15-3) and carcinoembryonic antigen (CEA), in breast cancers.

PATIENTS AND METHODS

Preoperative CA 15-3 and CEA levels of 1681 patients were measured. The association of both tumor markers levels with clinicopathological parameters and outcomes was investigated by univariate and multivariate analyses.

RESULTS

Among 1681 patients, elevated preoperative CA15-3 and CEA levels were identified in 176 and 131 patients, respectively. Higher preoperative CA 15-3 and CEA levels were significantly associated with a larger tumor size, axillary node metastases, and advanced stage. Patients with elevated CA 15-3 and CEA levels showed worse survival, even in stage-matched analysis. Patients with normal levels of both CA15-3 and CEA showed better survival than those with one or both markers levels elevated. In multivariate analysis, elevated preoperative CA 15-3 and CEA levels were independent prognostic factors. The statistical significance of elevated preoperative tumor markers levels on survival was solidified with longer follow-up and larger study population.

CONCLUSIONS

Elevated preoperative CA 15-3 and CEA levels are associated with tumor burden and showed independent prognostic significance. Therefore, new treatment strategies are necessary for patients with elevated preoperative CA 15-3 and CEA levels in clinical practice.

Predicting portal hypertension as assessed by acoustic radiation force impulse: correlations with the Doppler ultrasound

OBJECTIVE

The purpose of this study was to assess the value of acoustic radiation force impulse (ARFI) for evaluating portal hypertension by correlating the elasticity of liver cirrhosis, as measured by ARFI, with haemodynamic indices measured by Doppler ultrasound.

METHODS

We evaluated the data of a total of 154 prospectively enrolled patients who underwent both duplex Doppler ultrasound and ARFI imaging. The duplex Doppler ultrasound indices, including the mean portal vein velocity, splenic index (SI) and splenoportal index (SPI) were evaluated to determine the statistical correlation with shear wave velocity (SWV) of ARFI. We also analysed the differences in the correlations between the SI, SPI and SWV of the group who had varices. The correlations were assessed with Spearman's rank correlation coefficients.

RESULTS

There was an increase of SWV in parallel with the increase of the SI (ρ=0.409, p<0.01) and SPI (ρ=0.451, p<0.01). In the patient group who did not have varices (n=74), the Doppler indices were found to be more correlated with the SWV (SI: ρ=0.447, SPI: ρ=0.552, p<0.01). However, the group with varices showed no correlation between the SWV and the Doppler parameters.

CONCLUSION

SWV of ARFI was well correlated statistically with Doppler parameters, but is of limited value in predicting portal hypertension directly owing to great variability of Doppler parameters. By evaluating the correlation between ARFI and Doppler ultrasound, we suggest that the SWV might be a non-invasive supplementary tool for predicting portal hypertension.

Proteins involved in DNA damage response pathways and survival of stage I non-small-cell lung cancer patients

BACKGROUND

Biological complexity leads to significant variation in the survival of patients with stage I non-small-cell lung cancer (NSCLC). DNA damage response (DDR) pathways play a critical role in maintaining genomic stability and in the progression of NSCLC. Therefore, the development of a prognostic biomarker focusing on DDR pathways is an intriguing issue.

PATIENTS AND METHODS

Expression of several proteins (ATM, ATMpS1981, γH2AX, 53BP1, 53BP1pS25, Chk2, Chk2pT68, MDC1, MDC1pS964, BRCA1pS1423, and ERCC1) and overall survival were investigated in 889 pathological stage I NSCLC patients.

RESULTS

Low expression of BRCA1pS1423 or ERCC1 was significantly associated with worse survival in the whole cohort of patients. Analysis performed based on histology revealed that low expression of γH2AX, Chk2pT68, or ERCC1 was a poor prognostic factor in squamous cell carcinoma patients [adjusted hazard ratio (aHR), Cox P: 1.544, 0.012 for γH2AX; 1.624, 0.010 for Chk2pT68; 1.569, 0.011 for ERCC1]. The analysis of the interaction between two proteins showed that this effect was more pronounced in squamous cell carcinoma patients. However, these effects were not detected in adenocarcinoma patients.

CONCLUSIONS

The proteins involved in DDR pathways exhibited differential expression between squamous cell carcinoma and adenocarcinoma and were important determinants of survival in stage I squamous cell carcinoma patients.