Radiosensitizing Effects of CDK4/6 Inhibitors in Hormone Receptor-Positive and HER2-Negative Breast Cancer are through Downregulating DNA Repair Mechanism and NF-κB-Signaling Pathway

PURPOSE/OBJECTIVE(S)

CDK4/6 inhibitors combined with endocrine therapy are demonstrated to prolong survival for hormone receptor (HR)-positive and HER2-negative advanced breast cancer. We sought to assess whether cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitors can enhance the radiosensitivity and their underlying mechanisms in this subtype of breast cancer through both in vitro and in vivo approaches.

MATERIALS/METHODS

We used MCF-7 and T-47D (HR-positive and HER2-negative) breast cancer cell lines, and different doses of CDK4/6 inhibitors (ribociclib and palbociclib) and radiotherapy (RT) to assess the biological functions and mechanisms through in vitro study. The radiation enhancing effect was assessed by clonogenic assay, numbers of the DNA damage response-related molecules, γH2AX and 53BP1, were assessed by immunofluorescence. The p-ERK, c-Myc, and DNA-double strand break (DNA-DSB)-related molecules, p-DNA-PKcs, and p-ATM, were assessed by western blotting. We used NF-κB p65 Transcription Factor Assay Kit to evaluate the transcriptional activity of NF-κB. We evaluated the antitumor effect of combined RT (2 Gy every other day for total 6 Gy) and ribociclib through the MCF-7 orthotopic xenograft model.

RESULTS

The synergistic effects of combining RT with different concentrations of ribociclib and palbociclib pretreatment were demonstrated by colonogenic assay. We revealed that CDK4/6 inhibitors synergistically increased the numbers of RT-induced γH2AX and 53BP1, downregulated the expression of p-DNA-PKcs and p-ATM activated by RT, and diminished the expression of RT-triggering p-ERK expression, and NF-κB activation and its down-streaming gene, c-Myc. When compared with control, ribociclib, and RT group, combined ribociclib and RT significantly shrunk the tumor growth of MCF-7 cell xenograft tumors, and downregulated the immunohistochemical expression of p-ERK, p-NF-κB p65, and c-Myc than control group.

CONCLUSION

Our results demonstrated that combining CDK4/6 inhibitors enhanced the radiosensitivity in HR-positive and HER2-negative breast cancer cells, and conceivably radioenhancing mechanisms of CDK4/6 inhibitors are at least through lessening DNA-DSB repairing processes and weakening the activation of ERK signaling and NF-κB signaling by RT.

[Clinical features and prognostic factors of severe hemophagocytic syndrome in children]

Objective: To explore the clinical characteristics, prognostic risk factors and effective treatment of severe hemophagocytic syndrome (HPS) in children, so as to provide reference for the clinical diagnosis and treatment of the disease. Methods: The clinical data of 83 children with severe HPS admitted in Affiliated Hospital of Zunyi Medical University from January 2014 to April 2021 were collected, and their clinical characteristics, prognosis and prognostic risk factors were analyzed. The children were divided into central nervous system (CNS) dysfunction group and non-CNS dysfunction group according to whether they were accompanied with CNS dysfunction, and were divided into blood purification group and non-blood purification group according to whether they received blood purification, then the survival differences were compared. Results: Among the 83 children, there were 43 males and 40 females, aged[M(Q₁,Q₃)] 36(15,27)months. A total of 51 children were induced by infection, among which 41 children (80.4%) were infected with EB virus. All the children were accompanied by multiple organ dysfunction (MODS), and dysfunction of the blood system (72.3%), liver (71.1%), respiratory system (53.0%) and CNS (37.3%) were common. By the end of follow-up, 40 cases (48.2%) survived, 38 cases (45.8%) died, and 5 cases (6.0%) were lost to follow-up. CNS dysfunction was a risk factor (HR=3.358, 95%CI: 1.445-7.803, P=0.005) and blood purification was a protective factor (HR=0.362, 95%CI: 0.179-0.730, P=0.005) affecting the prognosis of children. The mortality of CNS dysfunction group was statistically higher than that of non-CNS dysfunction group (74.2% vs 28.8%) (P<0.001); The mortality of blood purification group was statistically lower than that of non-blood purification group (31.0% vs 61.0%) (P=0.010). Conclusions: Severe HPS in children was dangerous and had a poor overall prognosis. CNS dysfunction was a risk factor for death. Blood purification could significantly improve the prognosis and improve the survival rate of children.

Pathologic complete response (pCR) to neoadjuvant treatment with or without atezolizumab in triple negative, early high-risk and locally advanced breast cancer. NeoTRIP Michelangelo randomized study

BACKGROUND

High-risk triple negative breast cancers (TNBC) are characterized by poor prognosis, rapid progression to metastatic stage and onset of resistance to chemotherapy, thus representing an area in need of new therapeutic approaches. PD-L1 expression is an adaptive mechanism of tumour resistance to tumour infiltrating lymphocytes, which in turn are needed for response to chemotherapy. Overall, available data support the concept that blockade of PD-L1/PD-1 check-point may improve efficacy of classical chemotherapy.

PATIENTS AND METHODS

Two-hundred-eighty patients with TNBC were enrolled in this multicentre study (NCT002620280) and randomized to neoadjuvant carboplatin AUC 2 and nab-paclitaxel 125 mg/m² iv on days 1 and 8, without (N = 142) or with (N = 138) atezolizumab 1200 mg iv on day 1. Both regimens were given q3 weeks for 8 cycles before surgery and 4 cycles of an adjuvant anthracycline regimen. The primary aim of the study is to compare event-free survival, an important secondary aim was the rate of pathological complete remission (pCR defined as absence of invasive cells in breast and lymph nodes). The primary population for all efficacy endpoints is the intention-to-treat population.

RESULTS

The intention-to-treat analysis revealed that pCR rate after treatment with atezolizumab (48.6%) did not reach statistical significance compared to no atezolizumab [44.4%: odds ratio (OR) 1.18; 95% CI 0.74-1.89; P = 0.48]. Treatment-related adverse events were similar with either regimen except for a significantly higher overall incidence of serious adverse events and liver transaminases abnormalities with atezolizumab.

CONCLUSIONS

The addition of atezolizumab to nab-paclitaxel and carboplatin did not significantly increase the rate of pCR in women with TNBC. In multivariate analysis the presence of PD-L1 expression was the most significant factor influencing rate of pCR (OR 2.08). Continuing follow up for the event-free survival is ongoing, and molecular studies are under way.

Adjuvant abemaciclib combined with endocrine therapy for high-risk early breast cancer: updated efficacy and Ki-67 analysis from the monarchE study

BACKGROUND

Adjuvant abemaciclib combined with endocrine therapy (ET) previously demonstrated clinically meaningful improvement in invasive disease-free survival (IDFS) and distant relapse-free survival (DRFS) in hormone receptor-positive, human epidermal growth factor receptor 2-negative, node-positive, high-risk early breast cancer at the second interim analysis, however follow-up was limited. Here, we present results of the prespecified primary outcome analysis and an additional follow-up analysis.

PATIENTS AND METHODS

This global, phase III, open-label trial randomized (1 : 1) 5637 patients to adjuvant ET for ≥5 years ± abemaciclib for 2 years. Cohort 1 enrolled patients with ≥4 positive axillary lymph nodes (ALNs), or 1-3 positive ALNs and either grade 3 disease or tumor ≥5 cm. Cohort 2 enrolled patients with 1-3 positive ALNs and centrally determined high Ki-67 index (≥20%). The primary endpoint was IDFS in the intent-to-treat population (cohorts 1 and 2). Secondary endpoints were IDFS in patients with high Ki-67, DRFS, overall survival, and safety.

RESULTS

At the primary outcome analysis, with 19 months median follow-up time, abemaciclib + ET resulted in a 29% reduction in the risk of developing an IDFS event [hazard ratio (HR) = 0.71, 95% confidence interval (CI) 0.58-0.87; nominal P = 0.0009]. At the additional follow-up analysis, with 27 months median follow-up and 90% of patients off treatment, IDFS (HR = 0.70, 95% CI 0.59-0.82; nominal P < 0.0001) and DRFS (HR = 0.69, 95% CI 0.57-0.83; nominal P < 0.0001) benefit was maintained. The absolute improvements in 3-year IDFS and DRFS rates were 5.4% and 4.2%, respectively. Whereas Ki-67 index was prognostic, abemaciclib benefit was consistent regardless of Ki-67 index. Safety data were consistent with the known abemaciclib risk profile.

CONCLUSION

Abemaciclib + ET significantly improved IDFS in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative, node-positive, high-risk early breast cancer, with an acceptable safety profile. Ki-67 index was prognostic, but abemaciclib benefit was observed regardless of Ki-67 index. Overall, the robust treatment benefit of abemaciclib extended beyond the 2-year treatment period.

[A multicenter prospective randomized controlled clinical study of 5-fluorouracil in different mass concentrations combined with triamcinolone in the treatment of keloids]

Objective: To evaluate the clinical effects of 5-fluorouracil in different mass concentrations combined with triamcinolone in the treatment of keloids. Methods: From March 2018 to March 2019, 29 patients with 31 keloids receipted in the Department of Plastic Surgery of Fujian Medical University Union Hospital, 11 patients with 20 keloids receipted in the Department of Dermatology of Pingtan Comprehensive Experimental Area Hospital, and 9 patients with 9 keloids receipted in the Fuzhou Heisey-Dea Aesthetic Clinic were included in this prospectively randomized control study, with 27 males and 22 females, aged (30±9) years. According to the random number table, the keloids were divided into low mass concentration group (19 keloids, 17 patients), medium mass concentration group (21 keloids, 19 patients), and high mass concentration group (20 keloids, 17 patients). Then 5-fluorouracil at mass concentrations of 0.5, 5.0, and 12.5 mg/mL combined with triamcinolone acetonide were injected respectively, once every 4 weeks, for a total of 3 times. Before the first treatment and in 3 months after the last treatment, the appearance of keloids was evaluated by Vancouver Scar Scale (VSS) and pain and pruritus of keloids were evaluated by Visual Analogue Scale (VAS). Then the score differences before and after the treatment were calculated. In 6 months after the last treatment, the patients' efficacy satisfaction was evaluated by efficacy satisfaction rating scale. Adverse reactions during the treatment were recorded. In the follow-up of one year after the last treatment, the recurrence rates of keloids were counted. Data were statistically analyzed with chi-square test, one-way analysis of variance, paired sample t test, least significant difference t test, Wilcoxon rank sum test, Kruskal-Wallis rank sum test, or Fisher's exact probability test. Results: Before the first treatment, the appearance VSS scores of appearance of keloids in the three groups were similar (F=0.039, P>0.05). In 3 months after the last treatment, the appearance VSS scores of keloids in low mass concentration group were significantly higher than those in medium mass concentration group and high mass concentration group (t=2.267, 4.086, P<0.05 or P<0.01). In 3 months after the last treatment, the appearance VSS scores of keloids in low mass concentration group, medium mass concentration group, and high mass concentration group were significantly decreased compared with those before the first treatment (t=18.222, 44.272, 22.523, P<0.01). The differences of appearance VSS scores of keloids in low mass concentration group before and after treatment were significantly lower than those in medium mass concentration group and high mass concentration group (t=-4.096, -6.357, P<0.01), and the differences of appearance VSS scores of keloids in medium mass concentration group before and after treatment were significantly lower than those in high mass concentration group (t=-2.368, P<0.05). Before the first treatment, the pain and pruritus VAS scores of keloids in the three groups were similar (χ²=0.149, P>0.05). In 3 months after the last treatment, the pain and pruritus VAS scores of keloids in low mass concentration group were significantly higher than those in medium mass concentration group and high mass concentration group (Z=2.191, 4.386, P<0.05 or P<0.01), and the pain and pruritus VAS scores of keloids in medium mass concentration group were significantly higher than those in high mass concentration group (Z=2.276, P<0.05). In 3 months after the last treatment, the pain and pruritus VAS scores of keloids in medium mass concentration group and high mass concentration group were significantly decreased compared with those before the first treatment (Z=-3.904, -3.844, P<0.01). The differences of pain and pruritus VAS scores of keloids in low mass concentration group before and after treatment were significantly lower than those in medium mass concentration group and high mass concentration group (Z=-4.265, -6.104, P<0.01). In 6 months after the last treatment, the efficacy satisfaction scores of the corresponding patients of keloids were (88±8) points in high mass concentration group, which were significantly higher than (76±8) points in medium mass concentration group and (60±8) points in low mass concentration group (t=-3.820, -6.675, P<0.01), and the efficacy satisfaction scores of the corresponding patients of keloids in medium mass concentration group were significantly higher than those in high mass concentration group (t=-2.984, P<0.05). There was only statistically significant difference in pain within the 3 groups (P<0.01). In the follow-up of one year after the last treatment, the recurrence rate of keloids in high mass concentration group was significantly lower than that in low mass concentration group (χ²=8.313, P<0.01), and the recurrence rate of keloids in medium mass concentration group was similar to the recurrence rates in low mass concentration group and high mass concentration group (P>0.05). Conclusions: After treating keloids with high mass concentration of 5-fluorouracil combined with triamcinolone acetonide, the symptoms were significantly improved, the efficacy satisfaction of patients was increased, with no obvious adverse reactions but long lasting efficacy. Their overall effects are better than treatment using medium and low mass concentrations of 5-fluorouracil, which is worthy of clinical promotion.

Penetration of inferior alveolar nerve canal increased by bicortical fixation after bilateral sagittal split osteotomy in mandibular prognathism

The purpose of this three-dimensional cone beam computed tomography (CBCT) study was to identify the difference between monocortical fixation (MCF) and bicortical fixation (BCF) in mandibular canal penetration after bilateral sagittal split osteotomy (BSSO) to correct mandibular prognathism, where interosseous fixation was done by BCF or MCF. CBCT was performed 1 week postoperatively and Dolphin 3D software was used to assess direct penetration of the mandibular canal by either type of screw. The primary outcome variable was the presence or absence of mandibular canal penetration and was categorized as a binary coded variable. The BCF and MCF groups were compared by χ² test, and the odds ratio for canal penetration was estimated. Multiple logistic regression was performed to identify factors related to canal penetration. A total of 118 patients were included. The MCF group had only 6% canal penetrations (3/50 patients) and the BCF group had 58.8% canal penetrations (40/68 patients). The regression model showed that BCF was the only factor causing mandibular canal penetration, with an adjusted odds ratio of 52.5. Awareness of the increased risk of canal penetration with BCF and potential nerve injury might influence case selection.

Adjuvant T-DM1 versus trastuzumab in patients with residual invasive disease after neoadjuvant therapy for HER2-positive breast cancer: subgroup analyses from KATHERINE

BACKGROUND

In the KATHERINE study (NCT01772472), patients with residual invasive early breast cancer (EBC) after neoadjuvant chemotherapy (NACT) plus human epidermal growth factor receptor 2 (HER2)-targeted therapy had a 50% reduction in risk of recurrence or death with adjuvant trastuzumab emtansine (T-DM1) versus trastuzumab. Here, we present additional exploratory safety and efficacy analyses.

PATIENTS AND METHODS

KATHERINE enrolled HER2-positive EBC patients with residual invasive disease in the breast/axilla at surgery after NACT containing a taxane (± anthracycline, ± platinum) and trastuzumab (± pertuzumab). Patients were randomized to adjuvant T-DM1 (n = 743) or trastuzumab (n = 743) for 14 cycles. The primary endpoint was invasive disease-free survival (IDFS).

RESULTS

The incidence of peripheral neuropathy (PN) was similar regardless of neoadjuvant taxane type. Irrespective of treatment arm, baseline PN was associated with longer PN duration (median, 105-109 days longer) and lower resolution rate (∼65% versus ∼82%). Prior platinum therapy was associated with more grade 3-4 thrombocytopenia in the T-DM1 arm (13.5% versus 3.8%), but there was no grade ≥3 hemorrhage in these patients. Risk of recurrence or death was decreased with T-DM1 versus trastuzumab in patients who received anthracycline-based NACT [hazard ratio (HR) = 0.51; 95% confidence interval (CI): 0.38-0.67], non-anthracycline-based NACT (HR = 0.43; 95% CI: 0.22-0.82), presented with cT1, cN0 tumors (0 versus 6 IDFS events), or had particularly high-risk tumors (HRs ranged from 0.43 to 0.72). The central nervous system (CNS) was more often the site of first recurrence in the T-DM1 arm (5.9% versus 4.3%), but T-DM1 was not associated with a difference in overall risk of CNS recurrence.

CONCLUSIONS

T-DM1 provides clinical benefit across patient subgroups, including small tumors and particularly high-risk tumors and does not increase the overall risk of CNS recurrence. NACT type had a minimal impact on safety.

The impact of a surgery-first approach on oral health-related quality of life

Orthognathic surgery using a surgery-first approach (SFA) has been shown to result in better quality of life (QoL) throughout the treatment duration; however, the effects of gender, age and type of dentofacial deformity on SFA-related QoL remain unknown. In total, 228 consecutive patients underwent SFA for correction of dentofacial deformities (skeletal class III, bimaxillary protrusion and facial asymmetry). We assessed their QoL before surgery and at 1, 6 and 12 months after surgery using the Orthognathic Quality of Life Questionnaire (OQLQ). The results indicated a significant decrease in the total OQLQ, facial aesthetics and social aspect domain scores 1, 6 and 12 months after surgery. Among all domains, the greatest improvement was noted in the facial aesthetics domain. The oral function scores declined significantly immediately after surgery, but improved significantly 6 and 12 months after surgery; however, the awareness scores remained relatively stable. At each time point, women and the bimaxillary protrusion group exhibited a significantly higher total and specific domain scores. Patients aged 18-22 years exhibited lower total and four specific domain scores than older patients. Thus, QoL improves in all aspects, except awareness domain, by 12 months after SFA, but gender, age, and type of dentofacial deformity affect this improvement.

Abstract P4-04-09: Comparing tumor mutation burden detection between whole exome and target enrichment sequencing among Taiwanese breast cancers

Purpose: The ability to detect tumor mutation burden (TMB) is increasingly demanding and has become a pre-requisite for breast cancer personalized therapies, especially for those interrogating immune-modulating agents. The optimized quantification method determining TMB, however, remains inconclusive, and the current study compared tumor mutation yields among Taiwanese breast cancers, either with whole exome or target enrichment sequencing.

Methods: Sporadic breast cancers were prospectively recruited. Target-enrichment sequencing was performed with Illumina SolexaTM technology with read length of 150 paired ends and was analyzed with Agilent SureCallTM. There were 56 targets comprising 990 regions with a total regional size of 173.999 kbp. For whole exome sequencing, SureSelectTM Human All Exome V6r2 was adopted. The minimum coverage was set to 20 and the minimum alternative reads was set to 10 to enhance sequencing reliability. Samtools version 1.2 was utilized as variant caller for both whole exome and targeted sequencing. Novel and synonymous variants, as well as those located outside coding regions were removed. TMB was calculated as the number of somatic mutations per megabase (mb).

Results: A total of 61 and 52 Taiwanese breast cancers underwent target enrichment and whole exome sequencing, respectively. The number of somatic mutations ranged from 36 to 292 (median: 205), equivalent to 207~1678 (median: 1178) mutations/mb for targeted sequencing. On the other hand, there were 9947 to 10981 somatic mutations (median: 10727) when the whole exome was sequenced, resulting in TMB between 333 and 366 (median: 358). TMB for ER+/HER-, ER+/HER2+, ER-/HER2+, and ER-/HER2- was 1322 (n=31), 713 (n=11), 793 (n=10), and 1230 (n=9) for targeted sequencing and was 358 (n=29), 358 (n=12), 354 (n=5), and 357 (n=6) for whole exome sequencing. The most frequent nonsense mutations were NOTCH1 (S255*), RET (Q87*), KRAS (G57*), JAK3 (Y267*), and SMO (Y61*), while MAP2K1 (G148C), FNACA (G175V), BSG (H254P), ABL1 (T57P), and NOTCH1 (H416P) were the most common missense mutations.

Discussion and conclusions: High-throughput parallel massive sequencing can identify large numbers of variants, dependent both on the size of the sequenced regions and the variant caller algorithm utilized. Although Samtools identified more variants against reference than other methods, there should be no differential between whole exome and targeted sequencing. The number of somatic mutations, as well as the variability in TMB, was much higher in target enrichment approach than whole exome sequencing, highlighting that different TMB threshold should be established before wide clinical applications. Uneven distributions of “hotspot” mutation regions across genome as well as hundred-fold of sequencing length of whole exome versus targeted sequencing sequencing may contribute to such discrepancy.

Citation Format: Huang C-C, Huang C-S. Comparing tumor mutation burden detection between whole exome and target enrichment sequencing among Taiwanese breast cancers [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-04-09.

Abstract P6-02-13: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Huang C-S, Fann JC-Y, Chen H-H, Hsu G-C, Ho M-F, Chen S-C, Chen Y-J, Chen S-T, Chen C-Y, Sheen-Chen S-M, Chang H-T, Yeh D-C, Chao M, Yeh H-T, Cheng L, Chen D-R, Chang Y-C, Chang K-J. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-02-13.

Pharyngeal airway changes following maxillary expansion or protraction: A meta-analysis

The aim of this meta-analysis was to investigate the changes in airway dimensions after rapid maxillary expansion (RME) and facemask (FM) protraction. Using PubMed, Medline, ScienceDirect and Web of Science, only controlled clinical trials, published up to November 2016, with RME and/or FM as keywords that had ≥6 months follow-up period were included in this meta-analysis. The changes in pharyngeal airway dimension in both two-dimensional and three-dimensional images were included in the analysis. Nine studies met the criteria. There are statically significant changes in upper airway and nasal passage airway in the intervention groups as compared to the control groups, assessed in two-dimensional and three-dimensional images. However , in the lower airway and the airway below the palatal plane, no statistically significant changes are seen in 2D and 3D images. RME/FM treatments might increase the upper airway space in children and young adolescents. However, more RCTs and long-term cohort studies are needed to further clarify the effects on pharyngeal airway changes.

De-escalating and escalating treatments for early-stage breast cancer: the St. Gallen International Expert Consensus Conference on the Primary Therapy of Early Breast Cancer 2017

The 15th St. Gallen International Breast Cancer Conference 2017 in Vienna, Austria reviewed substantial new evidence on loco-regional and systemic therapies for early breast cancer. Treatments were assessed in light of their intensity, duration and side-effects, seeking where appropriate to escalate or de-escalate therapies based on likely benefits as predicted by tumor stage and tumor biology. The Panel favored several interventions that may reduce surgical morbidity, including acceptance of 2 mm margins for DCIS, the resection of residual cancer (but not baseline extent of cancer) in women undergoing neoadjuvant therapy, acceptance of sentinel node biopsy following neoadjuvant treatment of many patients, and the preference for neoadjuvant therapy in HER2 positive and triple-negative, stage II and III breast cancer. The Panel favored escalating radiation therapy with regional nodal irradiation in high-risk patients, while encouraging omission of boost in low-risk patients. The Panel endorsed gene expression signatures that permit avoidance of chemotherapy in many patients with ER positive breast cancer. For women with higher risk tumors, the Panel escalated recommendations for adjuvant endocrine treatment to include ovarian suppression in premenopausal women, and extended therapy for postmenopausal women. However, low-risk patients can avoid these treatments. Finally, the Panel recommended bisphosphonate use in postmenopausal women to prevent breast cancer recurrence. The Panel recognized that recommendations are not intended for all patients, but rather to address the clinical needs of the majority of common presentations. Individualization of adjuvant therapy means adjusting to the tumor characteristics, patient comorbidities and preferences, and managing constraints of treatment cost and access that may affect care in both the developed and developing world.

Toxicity profile differences of adjuvant docetaxel/cyclophosphamide (TC) between Asian and Caucasian breast cancer patients

AIM

For early-stage breast cancer, four cycles of docetaxel and cyclophosphamide (TC) was proven superior to doxorubicin plus cyclophosphamide in the US Oncology 9375 trial. Given primary prophylactic antibiotics, 5% febrile neutropenia was recorded in a population comprising 75.5% Caucasians. Smaller trials and retrospective studies reviewing TC use in Asian patients did not produce similar incidence rates. This study aims to discover the variable hematological toxicities with TC use in Caucasian and Asian patients.

METHODS

Breast cancer data was retrospectively reviewed for patients receiving adjuvant docetaxel 60-75 mg/m² plus cyclophosphamide 600 mg/m² from six countries (China, Hong Kong, Japan, Taiwan, Italy, and United States). Similar number of patients with relatively balanced baseline characteristics were chosen for analysis of hematological and nonhematological toxicities and survival data.

RESULTS

From March 2004 to July 2013, data of 227 patients (127 Asians and 100 Caucasian) patients were analyzed for treatment-related toxicities. During the four cycles of TC, Asians had a significantly higher rate of grade ≥2 neutropenia than Caucasians (45.7% vs 6.0%; P <0.001) and significantly more grade ≥3 neutropenia events were documented (respectively 30.7% vs 4.0%, P <0.001). The prophylactic use of G-CSF was similar; 26.0% in Asians and 28.0% in Caucasian (P = 0.764). There were no differences in nonhematological toxicities. No significant difference in disease-free survival was observed between Asians and Caucasians (log-rank P = 0.910).

CONCLUSIONS

Ethnic differences in toxicity profile exist between Asian and Caucasian patients given adjuvant TC. Over 30% Asians but less than 5% Caucasians experienced grade ≥3 neutropenia.

Abstract P2-03-11: Genomic pattern of breast carcinomas carrying mutations of non-BRCA homologous recombination genes

Background

BRCA1 and BRCA2 are involved in the homologous recombination (HR) double-strand DNA break repair and genomic patterns of breast tumors with defective BRCA are characterized by increased genomic instability. The pre-clinical and clinical studies show that tumors with defective BRCA or other HR genes can response to platinum and PARP inhibitors. However, the genomic pattern of tumors carrying mutations of non-BRCA HR genes are not investigated.

Methods

Genomic patterns of breast carcinomas were performed by comparative genomic hybridization (CGH) array containing 60000 probes covering the whole genome with an average spacing of 40kb. The frequency of gains and losses for each regions detected by probes was calculated by ratio thresholds of 0.25 and -0.25, respectively. Large-scale genomic structural aberration was defined as the region of gains and losses of at least 10Mb. We analyzed the difference of large-scale aberration, including numbers, length and specific regions, between tumors with BRCA mutation (mtBRCA), non-BRCA HR mutation (mtHR) and wild type.

Results

We examined 41 breast carcinomas, including 15 cases with BRCA mutations, 14 with non-BRCA HR gene mutations and 12 without mutations (control). The 14 non-BRCA HR gene were 1 ATM, 1 BRIP1, 1 BARD1, 1 FANCA, 2 FANCB, 1 FANCI, 1 PALB2, 2 RAD50, 2 RAD51C and 2 RAD51D. The number and length of large-scale genomic structural aberration of mtBRCA tumors were significantly higher than wild type tumors (number p=0.005; length p=0.005), indicating CGH can distinguish the mtBRCA from control tumors. We then checked the mtHR tumors, which also revealed significantly increased number and longer length of structural aberrations compared to wild type tumors (number p=0.035; length p=0.022), but were not different from mtBRCA tumors (number p=0.204; length p=0.425). Among the specific regions on chromosomes, mtBRCA and mtHR tumors contained similar genomic aberration regions but different from wild type tumors. The most frequent aberration regions of mtBRCA and mtHR tumors are chromosome 6p22.1-p25, 6q21-q27, 8q11.1-q24, 11p11.2-p14.1, 11q, 12p and 19p, which are less revealed in the wild type (all p value &lt;0.05).

Conclusions

Our study demonstrated a direct evidence that increased genomic instability were the common characteristics of mtBRCA and non-BRCA mtHR tumors. In addition, we identify the specific genomic patterns of mtBRCA and mtHR tumors, which can be a biomarker indicating HR deficiency and response to platinum and PARP inhibitors.

Citation Format: Lin P-H, Kuo W-H, Wang M-Y, Lo C, Lin C-H, Lu Y-S, Chiu C-F, Huang C-S. Genomic pattern of breast carcinomas carrying mutations of non-BRCA homologous recombination genes [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-03-11.

Abstract OT1-04-03: Randomized phase II study of induction bevacizumab, etoposide and cisplatin followed by whole brain radiotherapy (WBRT) versus WBRT alone in breast cancer with untreated brain metastases (A-PLUS)

Background For breast cancer (BC) patients with brain metastases (BM) who are not suitable for surgery/radiosurgery, whole brain radiotherapy (WBRT) remained the only standard treatment. Recently, we have demonstrated that bevacizumab preconditioning followed by etoposide and cisplatin (BEEP) is a highly effective treatment for BM of BC progressing from WBRT (Clin Cancer Res. 2015;21(8):1851). The CNS objective response rate is 77.1% according to volumetric criteria, and 60% according to RECIST 1.1. It has been demonstrated that enlarged brain tumor size is a predictor of WBRT failure. We hypothesized that, for BC with BM, induction BEEP treatment could decrease the size of brain metastases and thereby enhance effectiveness of WBRT. Methods This is a Phase II, randomized, open-labelled study (NCT02185352). Key inclusion criteria: BC with measurable brain metastatic tumor who had not received WBRT and not suitable for surgery or radiosurgery; KPS ≥30%. Key exclusion criteria: patients who had leptomeningeal metastases; history of disease progression during prior cisplatin treatment. In the experimental arm, patients will be treated by induction BEEP for three cycles followed by WBRT. In the control arm, patients will receive upfront WBRT for brain metastases. The BEEP regimen consist of bevacizumab (15 mg/kg) on Day 1 and, with a 1 day window period, followed by etoposide (70 mg/m2/day, Day 2 to Day 4) and cisplatin (70 mg/m2, Day 2), in a 21-day cycle. Stratification is based on the Graded Prognostic Assessment (GPA) score. Primary endpoint: brain-specific progression free survival (PFS) according to RECIST 1.1; key secondary endpoint: the 2-month brain-specific objective response rate (BS-ORR) of BEEP alone and WBRT alone. Other secondary endpoints include overall survival, extra-CNS tumor PFS, safety, time-to-improvement of neurological function,brain-specific PFS according to volumetric criteria, and BS-ORR. Approximately 126 patients will be 2:1 randomized. Multi-center recruitment is ongoing. To our knowledge this is the first randomized trial investigating a targeted therapy plus chemotherapy as induction regimen followed by WBRT as first line treatment for BC with BM.

Citation Format: Lu Y-S, Tseng L-M, Yu J-C, Rau K-M, Chao T-Y, Chen S-C, Chiu C-F, Chang Y-C, Chen TW-W, Lin C-H, Chang D-Y, Chao T-C, Huang S-M, Huang C-S, Cheng A-L. Randomized phase II study of induction bevacizumab, etoposide and cisplatin followed by whole brain radiotherapy (WBRT) versus WBRT alone in breast cancer with untreated brain metastases (A-PLUS) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT1-04-03.

Abstract P2-05-34: Risk stratification with EndoPredict signature for luminal subtype breast cancers: Re-analyzing microarray experiments with Han Chinese origin

Introduction: Breast cancer is a heterogeneous disease in terms of molecular aberrations. Luminal breast cancers, most of which are estrogen receptor (ER) positive without human epidermal growth factor receptor 2 (HER2) over expression clinically, constitute the majority of human breast cancers with better prognosis compared with basal-like or HER2-enriched subtype. The aim of the study is to evaluate the prognostication of EndoPredict signature, for which high- and low-risk group is defined based on a multi-gene assay. EndoPredict signature is supposed to guide adjuvant therapy for ER+/HER2- luminal breast cancers with up to three positive lymph nodes, while the test has not been validated for Han Chinese population yet.

Materials and methods: Our microarray experiments (partially published under GSE48391) and two publicly available microarray studies (GSE5460 and GSE20685) constituted the combined dataset of 565 breast cancers with Han Chinese origin, of which 280 were ER+/HER2- by immunohistochemical analysis. Transformation of Affymetrix microarray gene expression values to RT-qPCR-based expression values were conducted with the mathematical formula provided by the EndoPredict investigators, with gene-specific transformation factor and offset. Each enrolled patient was categorized into either high- or low-risk group based on the result of EndoPredict (EP) algorithm.

Results: Direct adaptation of the EP algorithm for microarray gene expression data resulted in over inflation of EP scores, and most cases were categorized into the high-risk group with the predefined threshold of EP score of 5 and adjustments with rescaling and relocations of microarray-based EP scores were performed. The proportion was 88% for low-risk group and 74% for high-risk group during the 10-year follow up period, with disease-specific survival advantage reported for those with EP-predicted low-risk group patients. On the other hand, borderline overall survival discrepancy was observed (89% for low-risk and 80% for high-risk group). In addition, patients with high-risk EP scores were associated with larger tumor size, higher nuclear grade, and more involved lymph nodes.

Risk stratificaiton of Taiwanese breast cancers by EP algorithm: disease-specific survivalRisk groupTotal numberFailed numberCensored numberPercentage of disease-specific survival censored patientsLow-risk6485687.5%High-risk1564011674.4%P=0.01, log-rank test

Risk stratificaiton of Taiwanese breast cancers by EP algorithm: overall survivalRisk groupTotal numberFailed numberCensored numberPercentage of overall survival censored patientsLow-risk6475789%High-risk1563112580.1%P=0.05, log-rank test

Discussion and conclusion: The study provides a solution to enhance the comparability between the FFPE/RT-qPCR based EP algorithms and fresh frozen microarray gene expression data. The statistical framework presented here provides an “in-silicon” validation for EP algorithm and further studies taking clinical parameters into consideration will augment the clinical applicability of EP scores and EPclin scores to ascertain the prognostic power of multi-gene assay for luminal breast cancers in Taiwan.

Citation Format: Huang C-C, Tsai M-L, Tu S-H, Huang C-S. Risk stratification with EndoPredict signature for luminal subtype breast cancers: Re-analyzing microarray experiments with Han Chinese origin [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-05-34.

Patterns of recurrence after oesophagectomy and postoperative chemoradiotherapy versus surgery alone for oesophageal squamous cell carcinoma

BACKGROUND

Patterns of recurrence after surgery with postoperative chemoradiotherapy (S-CCRT) or surgery alone in patients with oesophageal squamous cell carcinoma (SCC) may differ. This might influence the nature and timing of subsequent management strategies.

METHODS

Patients with SCC who had undergone R0 resection were included. Propensity score matching was used to select matched groups. Survival and recurrence were compared by Kaplan-Meier analysis. Univariable and multivariable Cox regression analyses were used to identify prognostic factors for overall and disease-free survival.

RESULTS

A total of 1390 patients were included, of whom 1000 had surgery alone and 390 underwent S-CCRT. Propensity score matching yielded 213 well balanced pairs. The 3-year overall survival rate and median survival time in the S-CCRT group were 0·50 and 36·5 (95 per cent c.i. 25·1 to 52·6) months respectively, compared with 0·38 and 22·8 (18·2 to 29·0) months in the surgery-alone group (P = 0·006). The 3-year disease-free survival rate and median disease-free survival time in the S-CCRT group were 0·46 and 30·6 (22·2 to 39·3) months respectively, compared with 0·36 and 17·6 (11·3 to 23·9) months in the surgery-alone group (P = 0·006). The 2-year freedom from locoregional recurrence rate was 0·87 and 0·77 in the S-CCRT and surgery-alone groups respectively (P = 0·003). In multivariable analysis, independent prognostic factors for disease-free survival included age over 56 years, pT3-4 category, pN category, poor differentiation, tumour length exceeding 4·0 cm, and receiving postoperative chemoradiotherapy (hazard ratio 0·62, 95 per cent c.i. 0·47 to 0·81; P < 0·001).

CONCLUSION

Oesophagectomy with postoperative chemoradiotherapy was associated with longer survival and lower recurrence rates, especially at a locoregional level, compared with surgery alone.

Nephrolithiasis among male patients with newly diagnosed gout

INTRODUCTION

An elevated serum urate level is recognised as a cause of gouty arthritis and uric acid stone. The level of serum uric acid that accelerates kidney stone formation, however, has not yet been clarified. This study aimed to find out if a high serum urate level is associated with nephrolithiasis.

METHODS

Patients were recruited from the rheumatology clinic of Taipei City Hospital (Renai and Zhongxing branches) in Taiwan from March 2015 to February 2016. A total of 120 Chinese male patients with newly diagnosed gout and serum urate concentration of >7 mg/dL and no history of kidney stones were divided into two groups according to their serum urate level: <10 mg/dL (group 1, n=80) and ≥10 mg/dL (group 2, n=40). The mean body mass index, blood urea nitrogen level, creatinine level, urinary pH, and kidney ultrasonography were compared between the two groups.

RESULTS

There were no significant differences in blood urea nitrogen or creatinine level between the two groups. The urine pH in both groups was similar and not statistically significant. Kidney stone formation was detected via ultrasonography in 6.3% (5/80) and 82.5% (33/40) of patients in groups 1 and 2, respectively (P<0.05).

CONCLUSION

A serum urate level of ≥10 mg/dL may precipitate nephrolithiasis. Further studies are warranted to substantiate the relationship between serum urate level and kidney stone formation.

Abstract P4-14-23: A phase I/II study of the combination of lapatinib and oral vinorelbine in HER2 positive metastatic breast cancer

Background The combination of lapatinib and oral vinorelbine for HER2 positive metastatic breast cancer (MBC) is appealing due to the convenience of oral combinations, but the overlapping toxicities may be of concern. A phase I/II study was designed to understand the tolerability and efficacy of this combination treatment.

Methods Female MBC patients (pts) with HER2 positive, but regardless of ER status, were eligible. In the phase I part, pts refractory to HER2-targeted treatment or chemotherapy were eligible. In the phase II part, only pts who had not exposed to HER2-targted treatment in the metastatic setting were eligible. Hormonal treatments were not allowed during the study for ER positive pts. Lapatinib was given once daily and oral vinorelbine was given on days 1 and 8 of a 21-day cycle. A 3+3 standard dose escalation rule was applied in phase I part (Table 1). The maximum tolerated dose (MTD) was the highest dose level with less than 33% of pts experiencing dose limiting toxicity (DLT) and will used as starting dose for phase II part. The primary endpoint of the phase II part was progression-free survival (PFS). Tumor response was assessed according to RECIST 1.1. Pt number estimation in the phase II part was based on Simon 2 stage design.

Results From 2009 Jun to 2013 Feb, a total of 46 pts were enrolled in phase I (n=15) and II (n=31) parts. The median age was 52.8 (range 34.3-84.0) and the median follow-up time was 39.2 months (range 6.1-62.2). Twenty-eight (60.9%) pts were ER positive. In the phase I part, 2 pts in dose level III had DLTs (Grade 3 neutropenia and grade 3 diarrhea (n=1), prolonged neutropenia delaying next cycle treatment (n=1)). Other common ≥40% grade 1/2 adverse events (AE) in the first-cycle include diarrhea (80.0%), skin rash (66.7%), fatigue (60.0%), and vomiting (40.0%). The MTD was determined at lapatinib 1000 mg plus oral vinorelbine 50 mg/m2. In the phase II part, 11 pts had intra-patient dose escalation of vinorelbine from 50 to 60 mg/m2 after first-cycle if no major toxicities were noted. Grade 3/4 AEs in the first-cycle include neutropenia, diarrhea, and infection in 12.9%, 3.2% and 3.2%, respectively. Grade 1/2 AEs were similar to the phase I results. Persistent treatment (in 8 cycles) increased the rate of grade 3/4 neutropenia (22.6%) and ALT/AST elevation (6.5%).The median PFS was 5.6 months (95% CI 5.2-5.9); 6 (19.4%) pts had PR, and the clinical benefit rate (CBR) was 38.7%. A higher dose (level III vs. level II) of vinorelbine was not associated with a better CBR (p=0.71), PFS (p=0.73), or OS (p=0.11). Among pts who had disease progression records, 13.2% (5/38) had brain metastasis progression. Long-term disease control (under treatment for more than 2 years) were achieved in 13.0% (6/46, 2 ER positive, 4 ER negative) pts.

Conclusion The combination of lapatinib 1000 mg and oral vinorelbine 60 mg/m2 was general tolerable with manageable toxicities. Clinical efficacy was demonstrated with long-term responders observed.

Table 1 Vinorelbine D1 & D8/21-day cycleLapatinib Daily/21-day cycleNo. of pt recruitedNo. of pt with grade 3/4 toxicities in first-cycle mg/m2mgN=15(I)+31(II)NLevel 030100030Level I40100030Level II5010006+206(II)Level III6010003+112(I)Level IV60125000

Citation Format: Chen TW-W, Yeh D-C, Chao T-Y, Lin C-H, Chow LW-C, Hsieh Y-Y, Huang S-M, Cheng A-L, Huang C-S, Lu Y-S. A phase I/II study of the combination of lapatinib and oral vinorelbine in HER2 positive metastatic breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-14-23.

Abstract P4-09-23: Gene expression signatures of microcalcifications among Taiwanese breast cancers

Introduction: Microcalcification is one of the most common radiological and pathological features of breast ductal carcinoma in situ (DCIS), and to a lesser extent, invasive breast cancer. In current study, we evaluated the transcriptional profiles associated with the phenomenon of ectopic mammary mineralization and a gene expression signature is derived.

Materials and methods: a total of 109 consecutive breast invasive cancers were prospectively collected and assayed with Affymetrix Human Genome U133 Plus 2.0 microarrays. The presence of microcalcification was confirmed by histopathological examinations as well as reviews of pre-operative mammography. The associations of gene expression profiles with microcalcifications and relevant clinical features such as DCIS including both comedo/high-grade and non-comedo subtypes were tested.

Results: Microcalcifications were presented in 84 (80%) of the study population as confirmed by pathological examination. Of these 84 patients, 81 (96%) were grown with coexistent DCIS microscopically, while only 8 (38%) of the 21 patients without concurrent microcalcifications, the invasive tumors were accompanied with DCIS (Chi-square test, P&lt;0.001). In addition, high-grade (comedo) type DCIS were presented in 44 (54%) of the 81 cancers with microcalcifications whereas only 15% (n=2) of tumors with DCIS but without microcalcificaitons were of high-grade (comedo) type. There were 69 genes differentially expressed between breast cancers with and without microcalcifications (nominal P&lt;0.001 with 10,000 random permutations), and 11 were associated with high-grade (comedo) type DCIS including APOD, CCDC183, SLMO1, SLC6A5, FMO1, QPRT and CES4A. The enriched Gene Ontology categories encompasses glycosaminoglycan, aminoglycan metabolic processes, Golgi apparatus cellular component and protein ubiquitination, indicating an active secretory process. The intersect (18 probesets) of microcalcificaion and DCIS-associated genes provided the best predictive accuracy of 82% with Bayesian compound covariate predictor.

Performance of compound covariate predictor classifier:ClassSensitivitySpecificityPPVNPVWith microcalcification0.8260.2170.7980.25Without microcalcification0.2170.8260.250.798

Compared with mammography alone, the diagnostic accuracy of gene expression-based signature is much improved (cross-validated ROC AUC: 0.738).

Discussion: Our study suggested that mammary microcalcification is not only the earlier detectable radiological finding for disease screening but the phenomenon itself resulted from distinct biological processes that constituted the molecular heterogeneity of human breast cancers. Further studies to evaluate the prognostic significance of microcalcifications are warranted.

Citation Format: Huang C-C, Huang C-S, Tu S-H, Tsai M-L. Gene expression signatures of microcalcifications among Taiwanese breast cancers. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-09-23.

Swimming exercise ameliorates neurocognitive impairment induced by neonatal exposure to isoflurane and enhances hippocampal histone acetylation in mice

Isoflurane-induced neurocognitive impairment in the developing rodent brain is well documented, and regular physical exercise has been demonstrated to be a viable intervention for some types of neurocognitive impairment. This study was designed to investigate the potential protective effect of swimming exercise on both neurocognitive impairment caused by repeated neonatal exposure to isoflurane and the underlying molecular mechanism. Mice received 0.75% isoflurane exposures for 4h on postnatal days 7, 8, and 9. From the third month after anesthesia, the mice were subjected to regular swimming exercise for 4weeks, followed by a contextual fear condition (CFC) trial. We found that repeated neonatal exposure to isoflurane reduced freezing behavior during CFC testing and deregulated hippocampal histone H4K12 acetylation. Conversely, mice subjected to regular swimming exercise showed enhanced hippocampal H3K9, H4K5, and H4K12 acetylation levels, increased numbers of c-Fos-positive cells 1h after CFC training, and less isoflurane-induced memory impairment. We also observed increases in histone acetylation and of cAMP-response element-binding protein (CREB)-binding protein (CBP) during the swimming exercise program. The results suggest that neonatal isoflurane exposure-induced memory impairment was associated with dysregulation of H4K12 acetylation, which may lead to less hippocampal activation following learning tasks. Swimming exercise was associated with enhanced hippocampal histone acetylation and CBP expression. Exercise most likely ameliorated isoflurane-induced memory impairment by enhancing hippocampal histone acetylation and activating more neuron cells during memory formation.

Evaluation of a pilot volunteer feeding assistance program: influences on the dietary intakes of elderly hospitalised patients and lessons learnt

OBJECTIVES

Malnutrition is a serious concern in hospitals and is known to be associated with increased complications for patients, increased hospital costs and length of stay. Trained volunteers that assist 'at risk' and malnourished patients at lunch meals have been shown to effectively increase nutritional intake in a suburban hospital in Sydney. The pilot study reported here aimed to evaluate and share learnings from a similar, newly implemented program, comparing energy and macronutrient intakes on days with no volunteer assistance, to days with volunteers.

DESIGN

Dietary intakes were determined by visual estimation of meal trays before and after meals, for two days without volunteers, and two days with volunteer assistance at lunch. Macronutrient and energy intakes were compared and data such as weight, height, diet type and medical history were obtained from medical records. Questionnaires were completed by nurses and volunteers in regards to their views and experiences with the program.

SETTING

Hospital based.

RESULTS

Eight patients (83±4.5 years) participated in the study. When volunteers were present at lunch, the average macronutrient and energy intakes increased, though not statistically significantly. The mean increases were 316 kJ (p=0.175) for energy, 3.1 g (p=0.468) for protein, 1.4 g (p=0.418) for fat and 11.6 g (p=0.084) for carbohydrates. Non-significant increases in macronutrients were also noted for the average daily intakes.

CONCLUSION

Although not statistically significant, energy and macronutrient intakes increased when volunteers were present. The implementation of a volunteer feeding assistance program is one strategy to assist dietary intakes but requires a ready team of volunteers, training, acceptance and significant time to develop.

BCAS2 promotes prostate cancer cells proliferation by enhancing AR mRNA transcription and protein stability

BACKGROUND

We showed previously that breast carcinoma amplified sequence 2 (BCAS2) functions as a negative regulator of p53. We also found that BCAS2 is a potential AR-associated protein. AR is essential for the growth and survival of prostate carcinoma. Therefore we characterised the correlation between BCAS2 and AR.

METHODS

Protein interactions were examined by GST pull-down assay and co-immunoprecipitation. Clinical prostate cancer (PCa) specimens were evaluated by immunohistochemical assay. AR transcriptional activity and LNCaP cell growth were assessed by luciferase assay and MTT assay, respectively.

RESULTS

BCAS2 expression was significantly increased in PCa. BCAS2 stabilised AR protein through both hormone-dependent and -independent manners. There are at least two mechanisms for BCAS2-mediated AR protein upregulation: One is p53-dependent. The p53 is suppressed by BCAS2 that results in increasing AR mRNA and protein expression. The other is via p53-independent inhibition of proteasome degradation. As BCAS2 can form a complex with AR and HSP90, it may function with HSP90 to stabilise AR protein from being degraded by proteasome.

CONCLUSIONS

In this study, we show that BCAS2 is a novel AR-interacting protein and characterise the correlation between BCAS2 and PCa. Thus we propose that BCAS2 could be a diagnostic marker and therapeutic target for PCa.

Abstract OT1-4-04: A phase II randomized, open-label, neoadjuvant study of LCL161, an oral antagonist of inhibitor of apoptosis proteins, in combination with paclitaxel in patients with triple-negative breast cancer

Background: Inhibitor of apoptosis proteins (IAPs) negatively regulate cell death through a variety of mechanisms. LCL161 is an oral small-molecule antagonist of IAPs that has demonstrated single-agent activity and synergy with paclitaxel in breast cancer tumor models. In preclinical studies, a gene expression signature has been shown to enrich for response to LCL161. The recommended dose of LCL161 1800 mg once weekly has demonstrated preliminary antitumor activity with paclitaxel in an ongoing Phase Ib study in patients with breast cancer.

Trial design: This is a Phase II, randomized, open-label study of neoadjuvant paclitaxel with or without LCL161 in women with operable, newly diagnosed triple-negative breast cancer (NCT01617668). Key inclusion criteria include women with histologically confirmed diagnosis of triple-negative breast cancer; clinical stages T2, N0–N2, M0; candidates for mastectomy or breast-conserving surgery; ECOG performance status ≤1; known status of the LCL161-predictive gene expression signature (positive and negative gene signature is a stratification factor); and adequate bone marrow and organ function. Key exclusion criteria are: bilateral or inflammatory breast cancer; locally recurrent breast cancer; patients currently receiving systemic therapy for any other malignancy, or having received systemic therapy for a malignancy in the preceding 3 months; impaired gastrointestinal function that may affect the absorption of LCL161; or uncontrolled cardiac disease.

Patients are randomized 1:1 to receive paclitaxel IV (80 mg/m2 weekly) with or without oral LCL161 (1800 mg once weekly) for 12 weeks (corresponding to 4 treatment cycles). Each treatment arm is stratified 1:1 based on gene expression signature status (positive or negative).

Endpoints: The primary endpoint is pathologic complete response (pCR), defined as the absence of invasive disease in the breast after 12 weeks of therapy, analyzed separately in the gene expression signature positive and negative groups. The key secondary endpoint is the pCR rate following treatment with LCL161 and paclitaxel in gene expression signature-positive or -negative tumors. Other secondary endpoints include: pCR rate in breast after 12 weeks of therapy in the full study population, and in patients with gene expression signature-positive and -negative tumors treated with paclitaxel alone; pCR rate in breast, regional nodes and axilla; biomarker evaluation including caspase 3 activation in tumor; safety; and pharmacokinetics of LCL161.

Statistical methods: pCR analysis will be performed according to treatment group and gene expression signature status. An absolute increase of at least 7.5% in pCR rate of the experimental arm over the control arm will be considered as evidence of clinically relevant efficacy.

Target accrual: Approximately 200 patients will be randomized into this study. Recruitment is ongoing across America, Europe, and Asia.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr OT1-4-04.

Abstract P3-06-02: Genetic polymorphisms from genome-wide association study associated with the metabolic and cell proliferation pathways affect the time to distant metastases of hormone receptor-positive and Her2-negative early breast cancer

Background: Single nucleotide polymorphisms (SNPs) identified from genome-wide association study (GWAS) have been found to be associated with breast cancer risk. We hypothesized that candidate genes and genes derived from GWAS involving in the Estrone/Estradiol (E2)/Tamoxifen biosynthesis may influence the adjuvant hormonal therapy effect and the survival. In this study, we sought to investigate whether these SNPs are associated with prognosis of hormone receptor (HR)-positive breast cancer patients, especially in HER2-negative patients.

Patients and methods: We selected breast cancer susceptibility SNPs identified by GWAS, SNPs in tamoxifen metabolizing related genes, and SNPs in estrogen receptor genes and estrogen metabolism genes, and genotyped for variations of above genes, including ALDH3A1, CYP2C19, COMT, CYP19, MAP3K1, FGFR2, TNRC9, HCN1, ERCC4, CYP3A5, UGT1A1, ER, ABCG2, CYP2B6, CYP2D6, 5p12 in 171 hormone receptor-positive, and Her2-negative early breast cancer patients (127 with negative lymph node [LN], and 44 with 1–3 positive LN). All patients received adjuvant hormonal therapy. The associations were examined between SNPs and distance disease-free survival (DDFS), and overall survival (OS) by using the log-rank test and Cox's proportional hazard model. Furthermore, we combined clinicopathologic features and SNPs into the risk score analysis to further validate above identified genetic markers.

Results: We found that SNPs of CYP2B6 (rs3211371), FGFR2 (rs2981582), and MAP3K1 (rs889312) were significantly associated with DDFS and OS. Furthermore, in lymph node-negative patients, CYP2B6 (rs3211371), FGFR2 (rs2981582), MAP3K1 (rs889312) and 5p12 (rs10941679 and rs4415084) were significantly associated with DDFS and OS, while CYP3A5 (rs776746) was significantly associated with OS but not DDFS. We further assessed the associations of disease prognosis with the number of high-risk genotypes in CYP3A5, FGFR2, and MAP3K1, and showed significant dose-response relationships between the number of high-risk alleles at these 3 loci and DDFS (P = 0.005 for trend) and OS (P = 0.0008 for trend). When combining the clinicopathologic features and SNPs into the risk score analysis, patients were divided into 3 subgroups (subgroup 1, risk score&lt;-1.438, n=43 [LN-positive, n=7]; subgroup 2, risk score between −1.438 and 1.708, n=85 [LN-positive, n=26]; subgroup 3, risk score&gt;1.708, n=43 [LN-positive, n=11]). We found that around 20 % of subgroup 3 patients had early development of distant metastases (DM) in the upfront 3 years (the trend of DM appeared to persist at least 10 years), and subgroup 2 patients had higher risk of DM after 5 years, whereas subgroup 1 patients had no development of DM even after 12 years.

Conclusion: Our results indicate that in addition to drug metabolic genes, genes related to cell proliferation, anti-apoptosis, and signaling transduction, for example, CYP3A5, CYP2B6, FGFR2, and MAP3K1 genes were associated with DDFS and OS in HR-positive/Her2-negative breast cancer patients. These findings provide additional insight that the genetic variants, or host factors, may affect the prognosis of breast cancer.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P3-06-02.

Abstract OT1-1-17: LUX-Breast 2: Phase II, open-label study of oral afatinib in HER2-overexpressing metastatic breast cancer (MBC) patients (pts) who progressed on prior trastuzumab and/or lapatinib*

Background: Management of HER2-overexpressing MBC has improved over the past decade. However, pts still develop resistance to currently available HER2-targeted therapies and novel effective treatments are increasingly required as dual targeted combinations are given in early treatment lines already. Current therapies focus on targeting HER2 and do not inhibit all relevant ErbB Family dimers. Afatinib is an oral, irreversible ErbB Family Blocker that inhibits signaling through activated EGFR (ErbB1), HER2 (ErbB2) and ErbB4 receptors and transphosphorylation of ErbB3. Preclinical studies have demonstrated efficacy in trastuzumab-sensitive, and trastuzumab-resistant human BC xenograft models dependent on ErbB signaling. Efficacy of afatinib in a trastuzumab-resistant SUM190 xenograft model has been shown to be increased by addition of intravenous (i.v.) vinorelbine. Afatinib monotherapy has shown promising clinical benefit in 46% of HER2-overexpressing MBC pts who progressed on prior trastuzumab, with 10% of pts achieving a partial response.1

Methods: This open-label Phase II trial (NCT01271725) investigates efficacy and safety of afatinib alone (40 mg/day) followed by afatinib ‘beyond progression’ in combination with chemotherapy in 120 pts with HER2-overexpressing MBC, who progressed on prior neoadjuvant and/or adjuvant trastuzumab and/or lapatinib. Pts who progress on afatinib monotherapy receive afatinib + either weekly paclitaxel 80 mg/m2 or vinorelbine i.v. 25 mg/m2. Eligible pts have confirmed HER2-overexpressing BC, Stage IV disease measurable by RECIST 1.1, progressed on trastuzumab and/or lapatinib therapy in either neoadjuvant and/or adjuvant setting, are eligible for retreatment with paclitaxel (i.e. should not have been pretreated with paclitaxel within the past 12 months), or are eligible for treatment with vinorelbine (i.e. should not have been pretreated with vinorelbine). Exclusion criteria include inadequate cardiac, renal, hepatic and hematological function, pre-existing gastrointestinal dysfunction, rapidly progressing visceral MBC, interstitial lung disease, and active brain metastases. The primary endpoint is objective response (OR) and secondary endpoints include best overall response, duration of OR, progression-free survival (PFS) and safety. PFS and safety will be assessed separately for afatinib mono- and combination therapy. An early stopping rule was deployed to minimize the number of pts treated should afatinib be ineffective; once 20 evaluable pts (according to RECIST 1.1) completed at least two courses of afatinib (or progressed during the first course), a meeting was held to evaluate the objective tumor response rate and to decide whether to proceed with the trial or stop due to futility. If at least one unconfirmed OR had been witnessed from all available information at the time, then the trial was to continue to full accrual. This early stopping rule for futility has been passed and the trial will continue to full accrual. Pt enrollment began in May 2011 in ∼40 sites and five countries.

1. Lin NU, et al. Breast Cancer Res Treat 2012. DOI: 10.1007/s10549-012-2003-y.

*Updated abstract from ASCO 2012.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr OT1-1-17.

Diffusion Tensor Imaging for Predicting Hand Motor Outcome in Chronic Stroke Patients

OBJECTIVE: Previous studies have indicated that diffusion tensor imaging (DTI) values are related to clinical outcome in stroke patients. This prospective study explored whether DTI values were predictive for hand function outcome in chronic stroke patients. METHODS: The DTI parameters (rλ1, rλ23, fractional anisotropy [rFA] and mean diffusivity [rMD]) were investigated in patients with completely paralysed hands (CPH; n = 10) or partially paralysed hands (PPH; n = 10), by two methods of analysis: segment of the corticospinal tract [sCST] analysis; pure region of interest [ROI] analysis. Spearman's correlation coefficient was used to assess the correlation between the DTI parameters and the following clinical measures: Fugl—Meyer Assessment [FMA]; National Institutes of Health Stroke Scale [NIHSS]. RESULTS: Significant differences were found between CPH and PPH for rFA and rλ23 (sCST analysis) and for rMD and rλ23 (ROI analysis). The rλ23 (sCST analysis) correlated with the NIHSS; the rMD (sCST analysis) correlated with the FMA (hand). CONCLUSION: The three parameters, rFA, rλ23 and rMD may have predictive value for evaluating hand function outcome in chronic stroke patients.

Lack of efficacy to systemic chemotherapy for treatment of metaplastic carcinoma of the breast in the modern era

Metaplastic carcinoma of the breast (MCB) is a rare subtype of breast cancer. Anecdotal reports are available regarding its response to systemic chemotherapy. We reviewed the records of patients diagnosed with MCB at National Taiwan University Hospital between 1988 and 2009. A total of 46 MCB cases were identified from 8,695 breast tumor patients who underwent biopsy or resection. About 11 of 25 patients with initial bulky disease (T3-4) received neoadjuvant chemotherapy before surgery, and 2 (18.2%) exhibited a partial response. About 12 of 18 patients who developed distant metastasis received palliative systemic chemotherapy. Of them, only 1 (8.3%), 1 (10%), and none (0%) responded to first-, second-, or third- and beyond line chemotherapy, respectively. None of the patients who received anthracyline- (n = 13), vinorelbine- (n = 7), or cyclophosphamide-based (n = 18) chemotherapy responded, whereas 3 (17.6%) of 17 patients who received taxane-based chemotherapy exhibited a partial response. Tumor response to systemic chemotherapy remains generally poor for MCB patients. Taxanes may have modest activity, but need to be validated in further studies.

Surgery-first accelerated orthognathic surgery: postoperative rapid orthodontic tooth movement

PURPOSE

Clinically, we have observed the phenomenon of postoperatively accelerated orthodontic tooth movement in patients who had orthognathic surgery. This phenomenon lasts for a period of 3 to 4 months. However, the underlying mechanisms of this phenomenon have not been well studied yet. The purpose of this prospective clinical pilot study was to study the postoperative changes in bone physiology and metabolism and the corresponding responses in the dentoalveolus, such as the changes in tooth mobility.

MATERIALS AND METHODS

Twenty-two consecutive adult patients who had 2-jaw orthognathic surgery were included in this study. The levels of serum alkaline phosphatase and C-terminal telopeptide of type I collagen (ICTP), as well as the tooth mobility of the maxillary and mandibular incisors based on the Periotest method (Siemens AG, Bensheim, Germany), were examined preoperatively and 1 week, 1 month, 2 months, 3 months, and 4 months postoperatively. The data were analyzed statistically.

RESULTS

Both tooth mobility of the maxillary and mandibular incisors and ICTP significantly increased from 1 week to 3 months postoperatively and then decreased to their preoperative levels in the fourth month postoperatively. The changes in tooth mobility were significantly in correspondence with the changes in ICTP. The alkaline phosphatase level significantly increased from the first to fourth month postoperatively, but it was not significantly correlated to the changes in tooth mobility.

CONCLUSION

The orthognathic surgery triggers a 3- to 4-month period of higher osteoclastic activities and metabolic changes in the dentoalveolus postoperatively, which possibly accelerates postoperative orthodontic tooth movement.

Multicolor fluorescence enhancement from a photonics crystal surface

A photonic crystal substrate exhibiting resonant enhancement of multiple fluorophores has been demonstrated. The device, fabricated uniformly from plastic materials over a ∼3×5 in.(2) surface area by nanoreplica molding, utilizes two distinct resonant modes to enhance electric field stimulation of a dye excited by a λ=632.8 nm laser (cyanine-5) and a dye excited by a λ=532 nm laser (cyanine-3). Resonant coupling of the laser excitation to the photonic crystal surface is obtained for each wavelength at a distinct incident angle. Compared to detection of a dye-labeled protein on an ordinary glass surface, the photonic crystal surface exhibited a 32× increase in fluorescent signal intensity for cyanine-5 conjugated streptavidin labeling, while a 25× increase was obtained for cyanine-3 conjugated streptavidin labeling. The photonic crystal is capable of amplifying the output of any fluorescent dye with an excitation wavelength in the 532 nm<λ<633 nm range by selection of an appropriate incident angle. The device is designed for biological assays that utilize multiple fluorescent dyes within a single imaged area, such as gene expression microarrays.

Dynamic seizure-related changes in extracellular signal-regulated kinase activation in a mouse model of temporal lobe epilepsy

Extracellular signal-regulated kinase (ERK) is highly sensitive to regulation by neuronal activity and is critically involved in several forms of synaptic plasticity. These features suggested that alterations in ERK signaling might occur in epilepsy. Previous studies have described increased ERK phosphorylation immediately after the induction of severe seizures, but patterns of ERK activation in epileptic animals during the chronic period have not been determined. Thus, the localization and abundance of phosphorylated extracellular signal-regulated kinase (pERK) were examined in a pilocarpine model of recurrent seizures in C57BL/6 mice during the seizure-free period and at short intervals after spontaneous seizures. Immunolabeling of pERK in control animals revealed an abundance of distinctly-labeled neurons within the hippocampal formation. However, in pilocarpine-treated mice during the seizure-free period, the numbers of pERK-labeled neurons were substantially decreased throughout much of the hippocampal formation. Double labeling with a general neuronal marker suggested that the decrease in pERK-labeled neurons was not due primarily to cell loss. The decreased ERK phosphorylation in seizure-prone animals was interpreted as a compensatory response to increased neuronal excitability within the network. Nevertheless, striking increases in pERK labeling occurred at the time of spontaneous seizures and were evident in large populations of neurons at very short intervals (as early as 2 min) after detection of a behavioral seizure. These findings suggest that increased pERK labeling could be one of the earliest immunohistochemical indicators of neurons that are activated at the time of a spontaneous seizure.

Antioxidant and pro-oxidant properties of chlorhexidine and its interaction with calcium hydroxide solutions

AIM

To evaluate the antioxidant and pro-oxidant properties of chlorhexidine (CHX).

METHODOLOGY

The scavenging and generation of reactive oxygen species (ROS) by CHX in the presence or absence of saturated Ca(OH)(2) solutions was evaluated. The reaction emitted chemiluminescence in the presence of lucigenin thus was determined by a luminometer to evaluate the levels of ROS production. Changes in DNA conformation were analysed by agarose gel electrophoresis. Paired Student's t-test was used to compare the difference between groups.

RESULTS

Chlorhexidine (0.00002-0.02%) effectively scavenged 56-88% of the superoxide radicals generated by the xanthine/xanthine oxidase reaction. Through analysis of PUC18 DNA conformation changes, CHX was shown to be a mild scavenger of hydroxyl radicals generated by H(2)O(2) plus FeCl(2). However, CHX (>0.083%) decreased the mobility of PUC18 plasmid DNA with potential production of DNA-DNA cross-link and severe DNA breaks (presence of DNA smear) at further higher concentrations. Furthermore, CHX induced ROS production including H(2)O(2) and superoxide radicals in 0.1N NaOH (pH = 12.76) or Ca(OH)(2) (pH = 12.5) solutions.

CONCLUSION

Chlorhexidine exhibited both antioxidant and pro-oxidant properties under different conditions. These events are possibly involved in the killing of root canal and periodontal microorganisms when CHX and Ca(OH)(2) were used in combination or separately. Potential genotoxicity and tissue damage when extruded into the periradicular tissue and at higher concentrations should be considered during periodontal and endodontic practice.

Combined UGT1A1 and UGT1A7 variant alleles are associated with increased risk of Gilbert’s syndrome in Taiwanese adults

Gilbert's syndrome (GS) is caused by a reduction in the activity of hepatic bilirubin UDP-glucuronosyltransferase (UGT). This reduction is associated with UGT1A1*28 and UGT1A1*6 polymorphisms. Recent research also showed that carriage of UGT1A1*6 allele were significantly related with UGT1A7*3. Polymerase chain reaction-restriction fragment length polymorphism were utilized to determine UGT1A7 and UGT1A1 genes for 207 patients with GS and 207 gender/age-matched healthy controls. For the 207 healthy controls, linkage disequilibrium was observed between -57UGT1A7 and 622UGT1A7 loci (D' = 1.00 and r(2) = 1.00), -57UGT1A7 and 211UGT1A1 loci (D' = 0.72 and r(2) = 0.36), respectively. A dose-response effect for number of at-risk allele of UGT1A1 and risk for GS was noted (odds ratio (OR) = 8.19 for heterozygous UGT1A1*28 genotype; OR = 124.96 for homozygous UGT1A1*28 genotype; and p for trend <0.05). Patients with combined genotypes carrying UGT1A7 variant alleles and UGT1A1 variant alleles (including UGT1A1*28 and UGT1A1*6) are associated with increased risk of GS (OR = 13.96 for patients with combined genotype carrying at least one variant allele of UGT1A1 and UGT1A7). In conclusion, the -57UGT1A7 (T>G) is highly associated with UGT1A7*3 and moderately associated with 211UGT1A1 (G>A). Certain UGT1A1/UGT1A7 combined genotypes are risk factors of GS.

Chylothorax following extended thymectomy for myasthenia gravis

The effectiveness of extended thymectomy for the treatment of myasthenia gravis is well documented. Most of the postoperative complications have been related to respiratory distress or wound complication, but chylothorax following thymectomy has been reported as a rare complication. From January 1995 to December 2004, 217 patients underwent extended thymectomy for myasthenia gravis at Taipei Veterans General Hospital. Three cases (1.38%) developed chylothorax after operation. Injury to the unseen division of the mediastinal lymphatics and branches from the thoracic duct during extensive dissection of perithymic fat tissue, which is seldom performed in classical thymothymectomy procedures, may have been the main cause of this complication. Two of the cases received conservative treatment and recovered uneventfully. The other patient (0.46%) underwent ligation of the thoracic duct 3 months later, which also resulted in the complication being cured.

CONCLUSIONS

Post-thymectomy chylothorax is rare and seems to be related to extended thymectomy. Even a small invasive procedure such as VATS for extended thymectomy formyasthenia gravis could be complicated by chylothorax. We recommend that if chylothorax develops after thymectomy, conservative treatment is the treatment of choice; however, thoracic duct ligation is a useful method for treating long-term unhealed chylothorax.

Supradiaphragmatic Ectopic Liver: Delayed Traumatic Hepatic Hernia Mimics Pulmonary Tumor

We present a rare case of a 63-year-old woman, the oldest one in the literature, with supradiaphragmatic ectopic liver that mimics a pulmonary nodule. The chest roentgenogram and chest computer tomography showed a lobulated tumor nearby the diaphragm. Pathological examination of the resected tumor disclosed only remarkable fatty liver change. Ectopic liver should be kept in mind to differentiate for the pulmonary tumor nearby the diaphragm.

B-group vitamins, MTHFR C677T polymorphism and carotid intima-media thickness in clinically healthy subjects

OBJECTIVE

Plasma B-group vitamins and age may affect the carotid intima-media thickness (IMT) in subjects with different 677TT genotype of the methylenetetrahydrofolate reductase (MTHFR) gene.

DESIGN

A hospital-based cross-study.

SETTING

Genomic and Vascular Center, Changhua Christian Hospital, Changhua, Taiwan.

SUBJECTS

Five hundred and forty-one clinically healthy subjects.

INTERVENTION

Fasting plasma, homocysteine (Hcy), vitamin B(6), vitamin B(12), folate and B-mode carotid ultrasound.

RESULTS

MTHFR genotype, plasma concentrations of folate, vitamin B(6) and vitamin B(12) and age were significantly correlated to the plasma Hcy concentration. MTHFR 677TT carriers had higher concentrations of Hcy than did subjects with the CC and CT genotypes. Age, sex, body mass index and plasma Hcy were independent contributors to increase carotid IMT. However, with stratification by mean value of age and B-group vitamins concentrations, we found that at advanced age, lower plasma folate and vitamin B(12) were three risk factors involved in the enhancing effect of the MTHFR 677TT genotype on the increase of plasma Hcy and carotid IMT.

CONCLUSION

MTHFR 677TT-related carotid atherosclerosis was only identified in healthy elderly subjects with lower level of plasma folate and vitamin B(12).

SPONSORSHIP

Changhua Christian Hospital.

Non-traumatic colon perforation in children: a 10-year review

Colon perforation is an abdominal surgical emergency in the pediatric population, but is seldom reported when occurring from non-traumatic causes in children beyond the neonate. The goal of this study was to identify the clinical characteristics, management, and outcomes of non-traumatic colon perforation in children. Medical records for the 10-year period from September 1994 to September 2004 were reviewed for children beyond the neonate with non-traumatic colon perforation. Data gathered included age, gender, symptoms, duration of symptoms, physical findings, and length of postoperative hospital stay. Diagnostic information included laboratory data, radiographic imaging, and operative findings. Forty-four patients with non-traumatic colon perforation were recruited into this study. The mean age was 2.22 +/- 1.87 years; 91.4% of cases were younger than 5 years old. The most common presenting symptom was fever (97.7%); the most common sign was abdominal distention (93.1%). The mean duration of symptoms prior to admission was 6.19 days. Pneumoperitoneum was presented in 86.3% of patients by plain abdominal radiograph. Ascending and transverse colon were the most common perforation sites. Non-typhoid salmonella was the leading pathogen isolated, causing 20.4% of episodes. One case died due to Clostridium speticum infection. Non-traumatic colon perforation most commonly affects children younger than 5 years of age. It may be secondary to infection, especially non-typhoid salmonella. Plain abdominal radiograph can be an adjuvant tool for the high index of suspicion for colon perforation in children with abdominal distention and history of fever or diarrhea for more than 5 days.

Differential expression of glucocorticoid receptor in human breast tissues and related neoplasms

Glucocorticoid receptor (GR) is a steroid hormone receptor that has been shown to play important roles in mammary development and differentiation, and has been implicated in breast tumourigenesis, but its precise biological significance in mammary pathophysiology remains unclear. In order to generate a comprehensive expression profile for GR in normal versus neoplastic breast tissues, GR expression was investigated in situ in 400 human breast tissue samples, comprising normal tissue and a range of benign, pre-invasive, and invasive lesions, using immunohistochemical assays. The novel expression of GR in myoepithelium, not observed in luminal epithelium, not only demonstrates expression patterns exclusive to the alpha form of oestrogen receptor and progesterone receptor and suggests distinctive functions between GR and these two important steroid hormone receptors in the breast, but may also indicate unique physiological and perhaps pathological roles for the myoepithelium in mediating the effects of glucocorticoid hormones in the breast. The strong expression of GR in metaplastic carcinomas (94.4%) and malignant phyllodes tumours (92.3%) suggests a pathogenetic role for GR, and implies that targeting GR in these tumours may have potential therapeutic application. However, studies on the roles of GR in mammary carcinogenesis should be interpreted with great caution, based on the lack of GR expression in cancer cells in the great majority (98.2%) of non-metaplastic carcinomas, which has gone unnoticed in previous studies. This marked discrepancy warrants a re-examination of the biological roles of GR in the pathophysiology of breast malignancy. The lack of methylation in the promoter region of the GR gene in all 118 non-metaplastic carcinomas, as demonstrated by methylation-specific PCR and bisulphite DNA sequencing analysis, indicates that methylation is less likely to play a role in the reduction of GR expression in non-metaplastic carcinoma of the breast.

The suppressed proliferation and premature senescence by ganciclovir in p53-mutated human non-small-lung cancer cells acquiring herpes simplex virus-thymidine kinase cDNA

The concerted actions of molecular networks determine how cells undergo proliferation, death or aging. Here we show that the highly invasive, tumorigenic human non-small-cell-lung cancer (NSCLC) cells carrying mutated p53 alleles were transfected with herpes simplex virus-thymidine kinase (HSV-tk) cDNA and the selected clone was susceptible to exogenous ganciclovir (GCV). The work further indicated that, in the stable HSV-tk transfectants, GCV suppressed cell proliferation by inducing G(2)/M cell cycle arrest and premature senescence and the potency can be amplified through bystander effect. The growth suppression of the established tumor xenografts in nude mice can be successfully targeted by GCV. These data showed that the GCV-suppressed tumor cell proliferation can be coordinated by cell cycle arrest and cellular senescence in HSV-tk transfectant lacking wild-type p53.

Factors influencing the outcome of transsternal thymectomy for myasthenia gravis

BACKGROUND

Thymectomy is one of the current treatment strategies for patients with myasthenia gravis (MG); however, the selection criteria for surgery remain controversial.

METHODS

The demographic data and the surgical results of 168 patients with MG who underwent transsternal thymectomy from June 1986 to December 2000 were retrospectively reviewed. Follow-up information was obtained by review of the hospital records or telephone contact. The postoperative status of MG was assessed at the interval of 1, 3 and 6 months and then annually. The complete remission rate (CRR) between groups was compared.

RESULTS

A total of 168 patients, including 69 male patients and 99 female patients, with a mean age of 38.3 years (range 13-80 years), were analyzed. The symptom duration before operations was from 1 to 312 months with a mean of 33.8 months. Complete follow-up information was obtained on 154 patients (91.6%) with a mean follow-up duration of 98.9 months. Complete remission was achieved in 89 of 154 patients (57.8%) and marked clinical improvement in 47 patients (30.5%). Total improvement rate was 88.3%. Seventeen of 24 patients (70.8%) with ocular MG and 18 of 35 patients (51.4%) with thymoma had reached complete remission during the follow-up period. The CRR increased with each consecutive year and reached the plateau in the fourth postoperative year. There was no surgical mortality. The complication rate was 16.6%. Univariate analysis demonstrated that age <35 years old (P = 0.0001), symptom duration before operation <24 months (P = 0.01) and absence of preoperative steroid treatment (P = 0.04) were favorable prognostic factors. Multivariate Cox regression analysis revealed age <35 years old (odds ratio = 3.645, P = 0.001), symptom duration before operation <24 months (2.311, P = 0.041) were favorable prognostic factors for patients having transsternal thymectomy.

CONCLUSIONS

Transsternal thymectomy is feasible in the management of patients with MG at all stages with high improvement rate and low surgical morbidity. Those patients aged 35 years or less at operation, with symptoms developed <24 months before operation, may benefit more from thymectomy. MG patients with thymoma did as well as patients without thymoma, and 18 of 35 patients with thymoma had reached complete remission during the follow-up period. Thymectomy seems to be beneficial also for ocular MG.

Prolene hernia system compared with mesh plug technique: a prospective study of short- to mid-term outcomes in primary groin hernia repair

Two types of anterior tension-free hernioplasty, prolene hernia system (PHS) repair and mesh plug technique (MPT), were introduced to Taiwan in 2001. This study compared the short- to mid-term outcomes following primary groin hernia repair with PHS and MPT. From January 2001 to December 2003, 393 patients with 426 primary groin hernias were operated on by a single surgeon using MPT (n=192) and PHS (n=234). Baseline perioperative details and follow-up information were compared. Demographic characteristics of both groups were similar. The laterality, types of anesthesia, postoperative stay, postoperative wound pain scores, wound complications and days to return to activities of daily life were equally distributed between the two groups. However, the distribution of Gilbert types in the PHS group was shifted a little to the right compared with that of the MPT group. PHS repair had longer operative time (34+/-17 vs 25+/-9 minutes, p<0.01). No recurrence was noted in both groups during the follow-up from 5 to 41 months. Chronic non-disabling groin pains were noted in 2.8% (6/218) of patients in the PHS group and 8.9% (14/175) in the MPT group (p=0.01). Our results show that both PHS and MPT repairs can be performed with short operation time, minor wound pain and quick return to activities of daily life without short- to mid-term recurrences, but postoperatively the MPT group had higher incidence of chronic non-disabling groin pain. Although the MPT is less invasive, the additional protective patch in the preperitoneal space of the PHS may provide a further safeguard against recurrences, especially for those patients with attenuated inguinal floor. Long-term follow-up is needed.

Long-term results of major bile duct injury associated with laparoscopic cholecystectomy

BACKGROUND

Major bile duct injury (MBDI) is the most serious complication associated with laparoscopic cholecystectomy (LC). This study reports on long-term outcomes and clinical factors which predicted the outcome of 25 patients with LC-associated MBDI.

METHODS

Twenty-five consecutive patients receiving either primary (n = 11) or redo (n = 14) biliary reconstructive surgery at Cathay General Hospital for LC-associated MBDI were prospectively followed for 2 to 10 (mean, 4.5) years to assess their long-term outcomes. Twelve clinical factors relevant to their outcomes were analyzed.

RESULTS

There was no mortality. Although the 1-year postoperative results were successful in 23 patients (92%), the mid- to long-term outcomes were successful in only 17 patients (68%). Eight patients (32%) developed biliary strictures at an average of 3.3 years postoperatively and required subsequent reoperation or biliary stenting. Statistical comparison of 12 risk factors between the successful and unsuccessful groups revealed that two were significant, namely, repair performed by a nonreferral surgeon (p = 0.02) and repair at a stage with recent active inflammation (p = 0.04). A serum alkaline phosphatase level greater than 400 IU in the sixth postoperative month was highly correlated with long-term nonsuccess (p = 0.01).

CONCLUSIONS

Only 68% of patients with LC-associated MBDI who underwent reconstructive surgery at our institution had long-term success. A serum alkaline phosphatase level above 400 IU in the sixth postoperative month was predictive of nonsuccess. For better long-term results, repair should be performed by the referral surgeon at a stage without coexisting active inflammation.

Intravenous immunoglobulin in the preparation of thymectomy for myasthenia gravis

OBJECTIVES

A clinical trial including six patients was conducted to assess the effect of intravenous immunoglobulin (IVIg) in the preparation of thymectomy for patients with myasthenia gravis (MG).

MATERIAL AND METHODS

Six consecutive patients of type IIB MG treated with IVIg at a dose 0.4 g/kg daily for 5 days before thymectomy were enrolled in this study.

RESULTS

All patients responded positively to this treatment. Improvement began to occur 1-9 days after starting the injection (mean 3.33 days), and reached a maximum in 3-19 days (mean 6.50 days). Thymectomy was performed 9-13 days (mean 11.20 days) after starting the injection in five of the six patients with uneventful post-operative courses.

CONCLUSION

IVIg might be an alternative to plasmapheresis (PE) in the prethymectomy preparation of MG patients, and thymectomy should be performed within 2 weeks after IVIg treatment to minimize the perioperative complications. Controlled trial vs PE enrolling more patients is needed to assess the significance of the IVIg in the preparation of thymectomy for patients of MG.

Scavenging property of three cresol isomers against H2O2, hypochlorite, superoxide and hydroxyl radicals

Formocresol has long been used for pulpotomy of primary teeth and as an intracanal medicament. Little is known, however, about the pharmacological effect of tricresols. This study showed that three cresol isomers, o-cresol, m-cresol and p-cresol, are H2O2 scavengers with a 50% inhibitory concentration (IC50) of 502, 6.7 and 10.16 microM, respectively. o-, m- and p-cresol were also shown to be effective scavengers of superoxide radicals generated by xanthine/xanthine oxidase with an IC50 of 282, 153 and > 4000 microM, respectively, as analyzed by luminometer. o-, m- and p-cresol showed protective effects on the DNA breaks generated by H2O2/FeCl2 and FeCl3/ascorbate/H2O2 systems at concentrations ranging from 70 microM to 1.43 mM, o-, m- and p-cresol also showed differential protective effects against DNA breaks induced by 0.17% NaOCl with 100% inhibitory concentration (IC100) of about 10, 1 and 10 mM, respectively. In addition, reaction with 3% H2O2 and 0.17% NaOCl completely prevented NaOCl-induced DNA breaks. The results indicate that the three cresol isomers are effective ROS scavengers and may prevent ROS induced damage when used as pulpotomy agents or as intracanal medicaments. Owing to the difference in the position of the functional hydroxyl group in the three cresol isomers, m-cresol is the most effective ROS scavenger. Concomitant use of H2O2 for root canal irrigation may diminish both the tissue dissolving capacity of NaOCl and NaOCl-induced DNA damage.

Point mutation in the alpha helix of the HLA-C alpha2 domain generates a novel HLA-C allele,HLA-Cw*0106, in a Han Chinese individual in Taiwan

We report herein the identification of a new HLA-C allele using sequence-based typing (SBT). This novel allele, HLA-Cw*0106, was found in a Han Chinese individual from Taiwan. This individual was typed using SBT as having a class I HLA genotype of HLA-A*0206/0207, HLA-B*4601/5601, and HLA-Cw*0102/0106. This new allele differs from HLA-Cw*0102 in one of the nucleotides of the polymorphic exon 3 at codon 152 (GAG-->GTG; E152V). This residue is located in the alpha helix of the HLA-C alpha2 domain and may have the potential to affect the binding of HLA-C molecules with antigenic peptides and/or the interactions with the T cell receptor. This new allele was detected in a few individuals of Han Chinese in Taiwan, but has not yet been observed in the aboriginal populations in Taiwan.

Cooperative binding of gamma-glutamyl substrate to human glutathione synthetase

Human glutathione synthetase is responsible for catalyzing the final step in glutathione biosynthesis. It is a homodimer with a monomer subunit MW of 52 kDa. Kinetic analysis reveals a departure from linearity of the Lineweaver-Burk double reciprocal plot for the binding of gamma-glutamyl substrate, indicating cooperative binding. The measured apparent K(m) values for gamma-glutamyl-alpha-aminobutyrate (an analog of gamma-glutamyl-alpha-aminobutyrate) are 63 and 164 microM, respectively. Neither ATP (K(m) of 248 microM) nor glycine (K(m) of 452 microM) exhibits such cooperative binding behavior. Although ATP is proposed to play a key role in the sequential binding of gamma-glutamyl substrate to the enzyme, the cooperative binding of the gamma-glutamyl substrate is not affected by alterations of ATP concentration. Quantitative analysis of the kinetic results for gamma-glutamyl substrate binding gives a Hill coefficient (h) of 0.75, indicating negative cooperativity. Our studies, for the first time, show that human glutathione synthetase is an allosteric enzyme with cooperative binding for gamma-glutamyl substrate.