[TGF-β3 improves bone mesenchymal stem cells toward chondrogenic differentiation under hypoxia environment]

Objective: To investigate the impact of TGF-β3 on the chondrogenesis of bone marrow mesenchymal stem cells (BM-MSCs) under hypoxia environment. Methods: BM-MSCs were obtained from SD rat tibias and femora and cultured with whole bone marrow adherent method. Cell surface antigens were analyzed by flow cytometry and the multiple-directional differentiation capabilities were detected with special differentiation agents to affirm the reality of BM-MSCs. Under normoxia or hypoxia condition, BM-MSCs were induced with TGF-β3 or not. Then, alcian blue and immunofluorescence staining were performed to evaluate the expression level of aggrecan, collagen Ⅱ. qRT-PCR analysis were performed to analyze the expression of aggrecan, collagen Ⅱ and collagen Ⅹ. qRT-PCR and Western blot analysis was performed to detect the mRNA and protein level of HIF-1α, collagenⅡ and β-catenin. Results: BM-MSCs were fibroblast-like shape and had ablities of osteogeic, adipogenic and chondrogenic differentiation, with the expression of CD(29, )CD(44) and CD(90) but not CD(45). Alcian blue and immunofluorescence staining showed that BM-MSCs strongly expressed the aggrecan and collagen Ⅱ with the presence of TGF-β3 under hypoxia condition. qRT-PCR analysis showed the mRNA expression levels of collagen Ⅱ, aggrecan and collagen Ⅹ were up-regulated at 2.46, 2.20 and 1.80 folds, comparing with control group (all P<0.05). Western blot analysis showed that the protein levels of HIF-1α, collagenⅡ in BM-MSCs were up-regulated with the presence of TGF-β3 under hypoxia condition, but β-catenin level was down-regulated. Conclusion: TGF-β3 promotes the chondrogenic differentiation ability of BM-MSCs under hypoxia condition, which may be relative with the inhibition of Wnt/β-catenin signaling pathway.

Intrapleural combination therapy with lobaplatin and erythromycin for non-small cell lung cancer-mediated malignant pleural effusion

BACKGROUND

Malignant pleural effusion is a common complication of non-small cell lung cancer (NSCLC); however, treatment options remain limited. This study evaluated the safety and efficacy of sequential intrapleural therapy with lobaplatin and erythromycin for NSCLC-mediated malignant pleural effusion.

METHODS

Fifty-six patients with NSCLC complicated with malignant pleural effusion were recruited for a prospective single-arm study from December 2014 to 2016; one patient dropped out. In addition to conventional systemic chemotherapy, lobaplatin and erythromycin were intrapleurally injected into subjects. Short and long-term responses were analyzed. The concentration of ultrafilterable platinum in the pleural effusion and plasma were detected at different time points. Incidences of severe adverse reactions were observed.

RESULTS

In the 55 evaluable patients, the effective rate of pleural effusion was 81.8% after six weeks of treatment. Six and twelve months after treatment, the effective rates were 60% and 21.8%, respectively, and the one-year survival rate was 83.6%. The concentrations of lobaplatin in pleural effusion and plasma two hours after injecting 50 mg lobaplatin into the thoracic cavity were 13.763 ± 1.523 μg/mL and 1.120 ± 0.164 μg/mL, and 17 hours later were 1.961 ± 0.351 μg/mL and 0.578 ± 0.095 μg/mL, respectively. The rate of severe adverse reactions of the first cycle of systemic chemotherapy combined with lobaplatin and erythromycin did not significantly differ from the rate in the second cycle.

CONCLUSION

Intrapleural combination therapy with lobaplatin and erythromycin is a safe and efficient treatment for patients with NSCLC-mediated malignant pleural effusion.

Postcontrast T1 Mapping for Differential Diagnosis of Recurrence and Radionecrosis after Gamma Knife Radiosurgery for Brain Metastasis

BACKGROUND AND PURPOSE

The differential diagnosis of radionecrosis and tumor recurrence in brain metastases is challenging. We investigated the diagnostic efficiency of postcontrast T1 mapping in solving this problem.

MATERIALS AND METHODS

Between March 2016 and June 2017, fifty-six patients with brain metastases who underwent contrast-enhanced cerebral T1 mapping were recruited for this prospective study. The findings revealed new enhancement after gamma knife radiosurgery. The subjects were assigned to radionecrosis and recurrence groups based on follow-up (median, 11.5 months) and histopathologic results. T1 values of lesions 5 (T1_5min) and 60 (T1_60min) minutes after administration of contrast agent and their difference (T1_differ) were compared between the 2 groups with the 2-tailed Mann-Whitney U test. Receiver operating characteristic curves were used to determine the optimum cutoff values for differential diagnosis.

RESULTS

There were significant differences between the 2 groups in T1_5min, T1_60min, and T1_differ values (P = .012, P = .004, and P < .001, respectively). Relative to T1_5min and T1_60min, T1_differ exhibited greater sensitivity and specificity (P < .001, respectively) in identifying radionecrosis. The optimum T1_differ value for differential diagnosis was 71.1 ms (area under the curve = 0.97; 95% CI, 0.93-1.00), with sensitivity and specificity of 81.5% and 96.5%, respectively.

CONCLUSIONS

Postcontrast T1 mapping is optimal for the differential diagnosis of radionecrosis and tumor recurrence. Among T1 parameters, T1_differ is the most powerful parameter for differential diagnosis. Advantages in terms of quantitative analysis and high resolution portend the wide use of postcontrast T1 mapping in the future.

[A comparative study of comprehensive geriatric assessment in elder patients with non-Hodgkin's lymphoma]

Objective: To measure the comprehensive geriatric assessment (CGA) in elder non-Hodgkin's Lymphoma (NHL) patients in a cross-sectional study; to compare the differences between Eastern Cooperative Oncology Group (ECOG)-performance status (PS) and CGA. Methods: CGA stratification included the following 3 instrument assessments: activity of daily living (ADL);instrumental activity of daily living (IADL);comorbidity score according to the modified cumulative illness rating score for geriatrics (MCIRS-G). According to CGA and age, NHL patients, aged ≥60 years, were classified as"fit","unfit"and"frail"groups. ECOG-PS was evaluated and compared with CGA. Results: According to CGA, 51.6% senior NHL patients (33 cases) were classified as"fit", 12.5%(8 cases) as"unfit"and 35.9%(23 cases) as"frail". Several comorbidities were observed in majority patients, such as cardiovascular disease, diabetes mellitus and hypertension. In the"younger aged"patients between 60 to 64ys, 25%(3/12) was considered as"frail". However, this proportion increased to 42.9%(6/14) in patients older than 80ys. Moreover, impaired CGA was observed in 38.9%(21/54) of ECOG-PS ≤1 patient. Conclusions: Impaired CGA is as common as approximately half in elderly NHL patients and more than one third even in ECOG-PS ≤1 patients. ECOG-PS may underestimate the impaired fitness function in elder NHL patients.

Nuclear factor erythroid 2-related factor 2 antioxidant response element pathways protect bovine mammary epithelial cells against H2O2-induced oxidative damage in vitro

The experiment was conducted to determine the role of nuclear factor (erythroid-derived 2)-like factor 2 (NFE2L2, formerly Nrf2) antioxidant response element (ARE) pathway in protecting bovine mammary epithelial cells (BMEC) against H₂O₂-induced oxidative stress injury. An NFE2L2 small interfering RNA (siRNA) interference or a pCMV6-XL5-NFE2L2 plasmid fragment was transfected to independently downregulate or upregulate expression of NFE2L2. Isolated BMEC in triplicate were exposed to H₂O₂ (600 μM) for 6 h to induce oxidative stress before transient transfection with scrambled siRNA, NFE2L2-siRNA, pCMV6-XL5, and pCMV6-XL5-NFE2L2. Cell proliferation, apoptosis and necrosis rates, antioxidant enzyme activities, reactive oxygen species (ROS) and malondialdehyde (MDA) production, protein and mRNA expression of NFE2L2 and downstream target genes, and fluorescence activity of ARE were measured. The results revealed that compared with the control, BMEC transfected with NFE2L2-siRNA3 had proliferation rates that were 9 or 65% lower without or with H₂O₂, respectively. These cells also had apoptosis and necrosis rates that were 27 and 3.5 times greater with H₂O₂ compared with the control group, respectively. In contrast, transfected pCMV6-XL5-NFE2L2 had proliferation rates that were 64.3% greater or 17% lower without or with H₂O₂ compared with the control group, respectively. Apoptosis rates were 1.8 times lower with H₂O₂ compared with the control. In addition, compared with the control, production of ROS and MDA and activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and glutathione-S-transferase (GST) increased markedly in cells transfected with pCMV6-XL5-NFE2L2 and without H₂O₂. However, compared with the control, production of ROS and MDA and activity of CAT and GSH-Px increased markedly, whereas activities of SOD and GST decreased in cells transfected with pCMV6-XL5-NFE2L2 and incubated with H₂O₂. Compared with the control, cells transfected with NFE2L2-siRNA3 with or without H₂O₂ had lower production of ROS and MDA and activity of SOD, CAT, GSH-Px, and GST. Cells transfected with pCMV6-XL5-NFE2L2 with or without H₂O₂ had markedly higher protein and mRNA expression of NFE2L2, heme oxygenase-1 (HMOX-1), NADH quinone oxidoreductase 1, glutamate cysteine ligase catalytic subunit, and glutamyl cystine ligase modulatory subunit compared with the control incubations. Cells transfected with NFE2L2-siRNA3 without or with H₂O₂ had markedly lower protein and mRNA expression of NFE2L2, HMOX-1, NADH quinone oxidoreductase 1, glutamyl cystine ligase modulatory subunit, and glutamate-cysteine ligase catalytic subunit compared with the control incubations. In addition, expression of HMOX-1 was 5.3-fold greater with H₂O₂ compared with the control. Overall, results indicate that NFE2L2 plays an important role in the NFE2L2-ARE pathway via the control of HMOX-1. The relevant mechanisms in vivo merit further study.

Rapid specific and visible detection of porcine circovirus type 3 using loop-mediated isothermal amplification (LAMP)

In this study, a rapid and specific assay for the detection of porcine circovirus type 3 (PCV3) was established using loop-mediated isothermal amplification (LAMP). Four primers were specifically designed to amplify PCV3. The LAMP assay was effectively optimized to amplify PCV3 by water bath at 60°C for 60 min. The detection limit was approximately 1 × 10¹ copy in this LAMP assay. Compared to porcine circovirus type 2 (PCV2), both gE and gD genes of pseudorabies virus (PRV) and porcine parvovirus (PPV), the LAMP assay showed a high specific detection of PCV3. A visible detection method was developed using SYBR Green I to recognize the results rapidly. Based on the detection of 20 clinical tissue samples, the LAMP assay was more practical and convenient than classical PCR due to its simplicity, high sensitivity, rapidity, specificity, visibility and cost efficiency.

Spatially fractionated (GRID) radiation therapy using proton pencil beam scanning (PBS): Feasibility study and clinical implementation

PURPOSE

GRID therapy is an effective treatment for bulky tumors. Linear accelerator (Linac)-produced photon beams collimated through blocks or multileaf collimators (MLCs) are the most common methods used to deliver this therapy. Utilizing the newest proton delivery method of pencil beam scanning (PBS) can further improve the efficacy of GRID therapy. In this study, we developed a method of delivering GRID therapy using proton PBS, evaluated the dosimetry of this novel technique and applied this method in two clinical cases.

MATERIALS/METHODS

In the feasibility study phase, a single PBS proton beam was optimized to heterogeneously irradiate a shallow 20 × 20 × 12 cm³ target volume centered at a 6 cm depth in a water phantom. The beam was constrained to have an identical spot pattern in all layers, creating a "beamlet" at each spot position. Another GRID treatment using PBS was also performed on a deep 15 × 15 × 8 cm³ target volume centered at a 14 cm depth in a water phantom. Dosimetric parameters of both PBS dose distributions were compared with typical photon GRID dose distributions. In the next phase, four patients have been treated at our center with this proton GRID technique. The planning, dosimetry, and measurements for two representative patients are reported.

RESULTS

For the shallow phantom target, the depth-dose curve of the PBS plan was uniform within the target (variation < 5%) and dropped quickly beyond the target (50% at 12.9 cm and 0.5% at 14 cm). The lateral profiles of the PBS plan were comparable to those of photon GRID in terms of valley-to-peak ratios. For the deep phantom target, the PBS plan provided smaller valley-to-peak ratios than the photon GRID technique. Pretreatment dose verification QA showed close agreement between the measurements and the plan (pass rate > 95% with a gamma index criterion of 3%/3 mm). Patients tolerated the treatment well without significant skin toxicity (radiation dermatitis grade ≤ 1).

CONCLUSIONS

Proton GRID therapy using a PBS delivery method was successfully developed and implemented clinically. Proton GRID therapy offers many advantages over photon GRID techniques. The use of protons provides a more uniform beamlet dose within the tumor and spares normal tissues located beyond the tumor. This new PBS method will also reduce the dose to proximal organs when treating a deep-seated tumor.

Presence of Torque teno sus virus 1 and 2 in porcine circovirus 3-positive pigs

In this study, the co-infection of Torque teno sus virus (TTSuV) and porcine circovirus type 3 (PCV3) was reported. One hundred and ten of 132 (83.3%) PCV3-positive samples were co-infected with Torque teno sus virus 1 (TTSuV1). Ninety-four of 132 (71.2%) PCV3-positive samples were co-infected with Torque teno sus virus 2 (TTSuV2). Sixty-six of 132 (50.0%) of PCV3-positive samples were co-infected with both TTSuV1 and TTSuV2. There were no clinical signs of infection in pigs that were both PCV3-positive and PCV2-negative, in either multiparous sows or live-born infants. The high co-infection rate provides valuable information for the further study of the pathological correlation between PCV3 and TTSuVs.

[Clinical analysis of cervical lymph node metastasis of cN0 maxillary malignant tumor]

OBJECTIVE

To investigate the cervical lymphatic metastasis rates of clinically negative neck lymph node (cN0) maxillary malignant tumors, to compare the cervical lymphatic metastasis rates of the various pathological types, and to provide the reference for the treatment of the neck of the patients with cN0 maxillary malignant tumor.

METHODS

The clinical data of 277 cases with cN0 maxillary malignant tumor, treated in the department of oral and maxillofacial surgery of Peking University School and Hospital of Stomatology from 1990 to 2010, were reviewed. The cervical lymph node metastasis and the related clinical information were recorded. The clinical information including histopathology type of the tumors, tumor grade, primary site and TNM staging, as well as other demographic and clinical data, were retrieved from the electronic medical record system (EMRS) of the hospital. The pathogenesis of cervical lymph node metastasis in maxillary malignant tumors of different histopathological types, and the factors related to lymph node metastasis of upper cervical malignancy were analyzed by SPSS 19.0 statistical software.

RESULTS

The overall cervical lymph node metastasis rate of the 277 patients with cN0 maxillary malignant tumor was 15.5% (43/277). Maxillary squamous cell carcinoma (SCC) had a strong cervical lymph node metastasis tendency and the rate was 33.0%. The overall metastatic rate of adenocarcinoma was 7.6% lower than that of SCC, and the occurrence of cervical lymph node metastasis time was relatively late, but the metastasis rate of highly malignant grade salivary gland carcinoma was significantly higher than that of intermediate and low grade carcinoma (P=0.037). The metastatic rates of some highly malignant cN0 salivary gland carcinomas including adenocarcinoma, not other specified, high-grade mucoepidermoid carcinoma (MEC), and salivary duct carcinoma were exceeded 15%, while the metastasis rates of adenoid cystic carcinoma and myoepithelial carcinoma were lower. The metastasis rate of the sarcomas was very low with the rate of 4.9%.

CONCLUSION

Selective neck dissection (SND) is recommended for cN0 maxillary SCC and feasible for some highly malignant cN0 salivary gland carcinomas including adenocarcinoma, not other specified, high-grade MEC, salivary duct carcinoma. The neck can be closely observed for the patients with maxillary sarcoma.

Abstract S4-02: The Y537S ESR1 mutation is a dominant driver of distant ER-positive breast cancer metastasis

Background: Estrogen receptor (ESR1) mutations occur at a high frequency in metastatic breast tumors in patients treated with hormonal therapy in the metastatic setting. We do not know if these mutations are involved in metastasis.

Experimental design and methods: We generated ESR1 Y537S homozygous mutations using CRISPR Casp-9 technology. Treatment synergy was evaluated using Compusyn. Athymic mice were used in tumor xenograft studies. ChIP-Seq and transcriptome analyses were performed.

Results: We generated CRISPR ESR1 Y537S mutation homozygous knock-in clones and lentiviral stable pools in MCF-7 cells. Transcriptome profiling revealed elevated expression of Hallmark pathways, including EMT and estrogen-regulated gene expression. The EMT in mutant cells was associated with a switch from E-cadherin to vimentin, and increased expression of SNAIL and TWIST. Mutant cell growth was resistant to tamoxifen, but responsive to fulvestrant treatment. Synergistic treatment effects were observed with fulvestrant and everolimus or palbociclib. CRISPR Y537S mutant knock-in cells grown in the mammary fat-pad of athymic mice spontaneously metastasized to distant organs including the lung, intestine, and kidneys. In the presence of estrogen, there was no difference in the frequency of distant macrometastases between parental wild-type ER and CRISPR Y537S mutant ER mice. However, in the absence of estrogen, 80% of CRISPR Y537S mutant ER mice displayed overt distant macrometastases, but none were observed in parental wild-type ER mice (p=0.04). Interestingly, although CRISPR Y537S mutant ER tumors grown in the mammary fat-pad were unresponsive to tamoxifen treatment, tamoxifen significantly inhibited the growth of mutant tumors at the distant microenvironment (8-fold). Distant tumors retained ER expression and hormone sensitivity. Comparison of residual tamoxifen-treated metastatic tumors with tumors grown at the primary mammary fat-pad site using immunoblot analysis demonstrated significant reduction in estrogen-regulated gene expression, but no effect on the expression of biomarkers associated with EMT, suggesting a disconnect between EMT and distant metastasis in mutant cells. EMT genes were also identified as direct binding site targets in Y537S mutant cells compared with wide-type ER using ChIPSeq. We discovered that expression of the Y537S mutant was dominant, driving the growth of distant metastatic tumors when co-expressed with wild-type ER cells. A Y537S ER mutant-specific gene expression signature predicted poor disease-free survival of ER-positive patients using the METABRIC database, and lung-specific metastasis-free survival in a Memorial Sloan Kettering dataset.

Conclusion: The Y537S ER mutation is a driver of distant metastasis in ER-positive breast cancer cells. Although tamoxifen treatment was ineffective at reducing the growth of mutant cells grown at the primary site, it was effective at reducing distant metastasis. A Y537S ER mutant-specific gene expression signature predicted poor disease-free, and distant lung metastasis in ER-positive patients. Mutation status is a potential new predictive factor for hormone therapy of metastatic breast cancer patients on maintenance hormonal therapy.

Citation Format: Fuqua SAW, Gu G, Rechoum Y, Gelsomino L, Dustin DJ, Corona-Rodriguez A, Beyer AR, Pejerrey SM, Gao M, Tsimelzon A, Tian L, Zhang X, Nagi C, Ando' S. The Y537S ESR1 mutation is a dominant driver of distant ER-positive breast cancer metastasis [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 S4-02.