Dietary elaidic acid boosts tumoral antigen presentation and cancer immunity via ACSL5

Immunomodulatory effects of long-chain fatty acids (LCFAs) and their activating enzyme, acyl-coenzyme A (CoA) synthetase long-chain family (ACSL), in the tumor microenvironment remain largely unknown. Here, we find that ACSL5 functions as an immune-dependent tumor suppressor. ACSL5 expression sensitizes tumors to PD-1 blockade therapy in vivo and the cytotoxicity mediated by CD8+ T cells in vitro via regulation of major histocompatibility complex class I (MHC-I)-mediated antigen presentation. Through screening potential substrates for ACSL5, we further identify that elaidic acid (EA), a trans LCFA that has long been considered harmful to human health, phenocopies to enhance MHC-I expression. EA supplementation can suppress tumor growth and sensitize PD-1 blockade therapy. Clinically, ACSL5 expression is positively associated with improved survival in patients with lung cancer, and plasma EA level is also predictive for immunotherapy efficiency. Our findings provide a foundation for enhancing immunotherapy through either targeting ACSL5 or metabolic reprogramming of antigen presentation via dietary EA supplementation.

Promising preclinical patient-derived organoid (PDO) and xenograft (PDX) models in upper gastrointestinal cancers: progress and challenges

Gastrointestinal (GI) cancers (gastric cancer, oesophageal cancer, liver cancer, colorectal cancer, etc.) are the most common cancers with the highest morbidity and mortality in the world. The therapy for most GI cancers is difficult and is associated with a poor prognosis. In China, upper GI cancers, mainly gastric cancer (GC) and oesophageal cancer (EC), are very common due to Chinese people's characteristics, and more than half of patients are diagnosed with distant metastatic or locally advanced disease. Compared to other solid cancers, such as lung cancer and breast cancer, personalized therapies, especially targeted therapy and immunotherapy, in GC and EC are relatively lacking, leading to poor prognosis. For a long time, most studies were carried out by using in vitro cancer cell lines or in vivo cell line-derived xenograft models, which are unable to reproduce the characteristics of tumours derived from patients, leading to the possible misguidance of subsequent clinical validation. The patient-derived models represented by patient-derived organoid (PDO) and xenograft (PDX) models, known for their high preservation of patient tumour features, have emerged as a very popular platform that has been widely used in numerous studies, especially in the research and development of antitumour drugs and personalized medicine. Herein, based on some of the available published literature, we review the research and application status of PDO and PDX models in GC and EC, as well as detail their future challenges and prospects, to promote their use in basic and translational studies or personalized therapy.

Repurposing drugs for solid tumor treatment: focus on immune checkpoint inhibitors

Cancer remains a significant global health challenge with limited treatment options beyond systemic therapies, such as chemotherapy, radiotherapy, and molecular targeted therapy. Immunotherapy has emerged as a promising therapeutic modality but the efficacy has plateaued, which therefore provides limited benefits to patients with cancer. Identification of more effective approaches to improve patient outcomes and extend survival are urgently needed. Drug repurposing has emerged as an attractive strategy for drug development and has recently garnered considerable interest. This review comprehensively analyses the efficacy of various repurposed drugs, such as transforming growth factor-beta (TGF-β) inhibitors, metformin, receptor activator of nuclear factor-κB ligand (RANKL) inhibitors, granulocyte macrophage colony-stimulating factor (GM-CSF), thymosin α1 (Tα1), aspirin, and bisphosphonate, in tumorigenesis with a specific focus on their impact on tumor immunology and immunotherapy. Additionally, we present a concise overview of the current preclinical and clinical studies investigating the potential therapeutic synergies achieved by combining these agents with immune checkpoint inhibitors.

A molecular classification system for estimating radiotherapy response and anticancer immunity for individual breast cancer patients

Objective

Radiotherapy is a cornerstone of breast cancer therapy, but radiotherapy resistance is a major clinical challenge. Herein, we show a molecular classification approach for estimating individual responses to radiotherapy.

Methods

Consensus clustering was adopted to classify radiotherapy-sensitive and -resistant clusters in the TCGA-BRCA cohort based upon prognostic differentially expressed radiotherapy response-related genes (DERRGs). The stability of the classification was proven in the GSE58812 cohort via NTP method and the reliability was further verified by quantitative RT-PCR analyses of DERRGs. A Riskscore system was generated through Least absolute shrinkage and selection operator (LASSO) analysis, and verified in the GSE58812 and GSE17705. Treatment response and anticancer immunity were evaluated via multiple well-established computational approaches.

Results

We classified breast cancer patients as radiotherapy-sensitive and -resistant clusters, namely C1 and C2, also verified by quantitative RT-PCR analyses of DERRGs. Two clusters presented heterogeneous clinical traits, with poorer prognosis, older age, more advanced T, and more dead status in the C2. The C1 tumors had higher activity of reactive oxygen species and response to X-ray, proving better radiotherapeutic response. Stronger anticancer immunity was found in the C1 tumors that had rich immune cell infiltration, similar expression profiling to patients who responded to anti-PD-1, and activated immunogenic cell death and ferroptosis. The Riskscore was proposed for improving patient prognosis. High Riskscore samples had lower radiotherapeutic response and stronger DNA damage repair as well as poor anticancer immunity, while low Riskscore samples were more sensitive to docetaxel, doxorubicin, and paclitaxel.

Conclusion

Our findings propose a novel radiotherapy response classification system based upon molecular profiles for estimating radiosensitivity for individual breast cancer patients, and elucidate a methodological advancement for synergy of radiotherapy with ICB.

Heterocyclic Molecular Targeted Drugs and Nanomedicines for Cancer: Recent Advances and Challenges

Cancer is a top global public health concern. At present, molecular targeted therapy has emerged as one of the main therapies for cancer, with high efficacy and safety. The medical world continues to struggle with the development of efficient, extremely selective, and low-toxicity anticancer medications. Heterocyclic scaffolds based on the molecular structure of tumor therapeutic targets are widely used in anticancer drug design. In addition, a revolution in medicine has been brought on by the quick advancement of nanotechnology. Many nanomedicines have taken targeted cancer therapy to a new level. In this review, we highlight heterocyclic molecular-targeted drugs as well as heterocyclic-associated nanomedicines in cancer.

High FAM111B expression predicts aggressive clinicopathologic features and poor prognosis in ovarian cancer

BACKGROUNDS

Ovarian cancer (OC) is the second most common gynecological tumor with the highest mortality rate worldwide. High FAM111B expression has been reported as a predictor of poor prognosis in other cancers, but its correlation with OC has not been reported.

METHODS

Immunohistochemistry of tissue microarrays was performed to detect FAM111B expression levels in 141 OC patient tissues. The prognostic value of FAM111B was determined by Kaplan-Meier survival analysis, and correlations between FAM111B expression and clinicopathologic features were investigated by the Clu-square test. The significance of FAM111B expression was verified bioinformatically using the Gene Expression Omnibus database. Protein-protein interaction were performed to explore downstream mechanisms of FAM111B in OC.

RESULTS

Among 141 OC patients, FAM111B was positively expressed in 87.23%, 58.16%, and 87.94%; and highly expressed in 8.51%, 17.02%, and 19.86%, as evaluated by cytoplasmic, nuclear, and combined cytoplasmic/nuclear staining. FAM111B expression was positively correlated with the expression of tumor protein markers KI67, EGFR, and PDL-1. Patients with high FAM111B expression had aggressive clinicopathologic features and shorter overall survival (P value 0.0428, 0.0050, 0.0029) and progression-free survival (P value 0.0251, 0.012, 0.0596) compared to the low FAM111B expression group for cytoplasmic, nuclear, and combined cytoplasmic/nuclear groups, respectively. These results were verified using patient data from the Gene Expression Omnibus. Seventeen genes co-expressed with FAM111B were primarily involved in "negative regulation of histone modification", "hippo signaling" and "inner ear receptor cell differentiation".

CONCLUSIONS

High FAM111B expression may serve as a novel prognostic predictor and molecular therapeutic target for OC.

Should we initiate oral anticoagulants for patients with atrial fibrillation staying well without oral anticoagulants for years?

Background

Although non-vitamin K antagonist oral anticoagulants (NOACs) were more and more commonly prescribed for stroke prevention for patients with atrial fibrillation (AF), underuse of OACs is still not uncommon. Data about the initiations of OACs in AF patients who did not experience ischemic stroke without any OACs for years since incident AF was diagnosed were limited. We aimed to investigate the associations between the initiations of warfarin or NOACs and clinical outcomes among this population.

Methods

From January 1st, 2007 to December 31st, 2010, a total of 167,176 newly-diagnosed AF patients aged ≥20 years were identified from the Taiwan National Health Insurance Research Database as the study population. Among the study population, 32,917 patients with a CHA2DS2-VASc score >1 for males or >2 for females who did not receive warfarin or NOACs and survived for at least 90 days after June 1st, 2015 were defined as the “original non-OAC cohort”. These patients were then categorized into 3 groups according to the stroke prevention strategies they received after June 1st, 2015; that is, without OACs (n=31,195), warfarin (n=230) and NOACs (n=1,492).

Results

Compared to patients staying on non-OACs, the risk of ischemic stroke was lower for patients who initiated NOACs (aHR 0.867; p=0.043). The risk of all-cause mortality was lower for patients who started to receive warfarin (aHR 0.876; p=0.036) or NOACs (aHR 0.798; p=0.047). The composite risk of ischemic stroke or major bleeding was also lower for patients who initiated warfarin (0.849; p<0.001) or NOACs (0.789; p<0.001) (Figure 1). Compared to warfarin, NOACs use was associated with a lower risk of ischemic stroke (aHR 0.819; p<0.001), ischemic stroke or intracranial hemorrhage (aHR 0.927; p=0.042) or ischemic stroke or major bleeding (aHR 0.912; p<0.001).

Conclusions

Initiations of OACs, especially NOACs, should still be considered for AF patients who stayed well without OACs for years since incident AF was diagnosed.

Funding Acknowledgement

Type of funding sources: None.

Early rhythm-control therapy in patients with atrial fibrillation: a nationwide cohort study

Background

In the Early Treatment of Atrial Fibrillation for Stroke Prevention Trial (EAST-AFNET 4), early rhythm control was associated with better clinical outcomes for patients with atrial fibrillation (AF). However, the intervention arm had more structured and regular followup, and whether the better outcomes of patients assigned to rhythm control were solely due to “early” intervention or because of more regular and structured follow up was unclear.

Purpose

We aimed to investigate whether the findings of the EAST trial are applicable to the “real world” clinical setting, where a less structured management protocol is operated.

Methods

From 2001 to 2016, 301,064 newly-diagnosed AF patients were identified from Taiwan National Health Insurance Research Database. Among these patients, 62,649 AF patients receiving antiarrhythmic drugs or catheter ablation within 1 year after AF being diagnosed (similar to the timing definition of the EAST-AFNET 4 trial) were categorized as the early rhythm control group, and the remaining 238,415 patients were defined as usual care group. Risk of clinical events were compared between 2 groups.

Results

Compared to usual care, early rhythm control was associated with a lower adjusted risk of ischemic stroke (aHR 0.771, 95CI 0.751–0.792; p<0.001), heart failure (aHR 0.851, 95% CI 0.806–0.891; p<0.001), acute myocardial infarction (aHR 0.915, 95% CI 0.877–0.955; p<0.001), mortality (aHR 0.794, 95% CI 0.782–0.806; p<0.001) and composite adverse events (aHR 0.823, 95% CI 0.813–0.834; p<0.001) (Figure). Compared to usual care, the lower risks of ischemic stroke (aHR 0.746, 95% CI 0.717–0.775), heart failure (aHR 0.819, 95% CI 0.798–0.841), mortality (aHR 0.777, 95% CI 0.759–0.795) and composite adverse events (aHR 0.802, 95% CI 0.787–0.818) associated with early rhythm control were even more evident when performed early (<3 months) than later periods (3–6 months, 7–9 months and 10–12 months; pint <0.001). Principal results were generally consistent for majority of subgroups studied and among the cohort after the propensity matching.

Conclusions

In this nationwide cohort study, early rhythm control therapy was associated with a lower risk of adverse events than usual care among patients with early AF. Outcomes were even better with earlier (<3 months) intervention.

Funding Acknowledgement

Type of funding sources: None.

Clinical significances of prothrombin time-international normalized ratio and activated partial thromboplastin time in patients with atrial fibrillation treated with direct oral anticoagulants

Background

Although the measurements of PT-INR or aPTT were not performed for patients with atrial fibrillation (AF) taking direct oral anticoagulants (DOACs) in randomized trials, these tests were commonly used and familiar to clinical physicians. We aimed to test whether there is an association between PT-INR or aPTT ratio and risks of ischemic stroke/systemic embolism (IS/SE) and major bleeding among AF patients taking rivaroxaban or dabigatran, respectively.

Methods

This multi-center cohort study included 3,192 AF patients taking rivaroxaban and 958 patients taking dabigatran for stroke prevention whose data about PT-INR and aPTT were available.

Results

For patients treated with rivaroxaban, a higher INR level was not associated with a higher risk of major bleeding compared to an INR level <1.1. The risk of IS/SE was lower for patients having an INR ≥1.5 compared to those with an INR <1.1 (aHR: 0.57; [95% CI: 0.37–0.87]; P=0.0088) (Figure). On-label dosing of rivaroxaban and use of digoxin were independent factors associated with an INR ≥1.5 after taking rivaroxaban. For patients taking dabigatran, a higher aPTT ratio was not associated with a higher risk of major bleeding. The risk of IS/SE was lower for patients having an aPTT ratio of 1.1–1.2 and 1.3–1.4 than those with an aPTT ratio <1.1.

Conclusions

In Asian AF patients, PT-INR or aPTT ratios were not associated with the occurrences of bleeding events for rivaroxaban or dabigatran. Patients taking rivaroxaban with an INR ≥1.5 were associated with a lower risk of IS/SE. Appropriate dosages of DOACs and the compliances of patients should be confirmed for patients taking rivaroxaban with an INR <1.5.

Funding Acknowledgement

Type of funding sources: None.

Impacts of off-label dosing noacs on clinical outcomes in very elderly patients with atrial fibrillation

Background

Studies about the comparisons of on-label and off-label dosing non-vitamin K antagonist oral anticoagulants (NOACs) regarding the risks of clinical outcomes among atrial fibrillation (AF) patients have been published. However, data among the very elderly AF patients were limited. In the present study, we aimed to investigate the impacts of inappropriate dosing of NOACs on clinical outcomes in AF patients aged ≥85 years of age.

Methods

We used medical data from a multi-center healthcare system in Taiwan enrolling 1,836 and 268 AF patients aged ≥85 years treated with NOACs and warfarin, respectively. Among 1,836 patients receiving NOACs, underdosing, overdosing and on-label dosing NOACs were prescribed in 248, 149 and 1439 patients, respectively. The risks of ischemic stroke/systemic embolism (IS/SE) and major bleeding were compared between warfarin and NOACs in different dosing groups. Also, the risks of clinical events of underdosing and overdosing NOACs were comapred to on-labeling dosing.

Results

Compared to warfarin, underdosing NOACs were associated with a higher risk of IS/SE (aHR 2.39; p=0.048) without a lower risk of major bleeding; while overdosing NOACs were not associated with a lower risk of IS/SE (aHR 0.74, p=0.604) (Figure 1). Compared to on-label dosing NOACs, underdosing NOACs were associated with a higher risk of IS/SE, while the risk was not lower for overdoing NOACs (Figure 2).

Conclusions

Even for very elderly AF patients aged ≥85 years, NOACs should still be prescribed at the dosing following the criteria defined in clinical trials and guideline recommendations.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Stroke prevention with non-vitamin K antagonist oral anticoagulants in high risk elderly atrial fibrillation patients at increased bleeding risk

Background

Elderly atrial fibrillation (AF) patients with risk factors of bleeding are often considered ineligible for standard oral anticoagulants (OACs). The ELDERCARE-AF trial recently showed that edoxaban 15mg/day was superior to placebo for preventing stroke or systemic embolism and did not result in a significantly higher incidence of major bleeding. Our aim was to investigate a real-world cohort of AF patients similar to the ELDERCARE-AF cohort, with regard to the impact of non-vitamin K antagonist oral anticoagulant (NOAC) use compared to non-OAC use, in relation to clinical outcomes.

Methods

From January 1, 2012 to December 31, 2016, 15,183 AF patients aged ≥80 years (mean age 86.63 years [SD 4.79]; 48.7% male) with a CHADS2 score >2 who met the enrollment criteria (generally similar to ELDERCARE-AF) were identified from the Taiwan National Health Insurance Research Database. Patients were categorized into 2 groups according to their stroke prevention strategies, ie. without OACs (n=9,084) and NOACs (n=6,099). Patients receiving NOACs were further stratified into reduced-dose or full-dose regimen groups.

Results

Compared to the non-OAC group as a reference, NOAC use (whether as reduced dose or full dose) was associated with a lower risk of ischaemic stroke (adjusted hazard ratio [aHR] 0.766, 95% confidence interval [CI] 0.667–0.879) and all-cause mortality (aHR 0.393, 95% CI 0.370–0.418) while the risks of ICH and major bleeding were similar. The risks of composite outcomes of “ischaemic stroke or mortality” (aHR 0.423, 95% CI 0.398–0.449) and “ischaemic stroke or major bleeding or mortality” (aHR 0.490, 95% CI 0.463–0.518) were significantly lower with NOAC use. When compared to non-OAC as the reference groups, NOACs (whether reduced dose or full dose) showed a positive NCB. The results were generally consistent even after the propensity matching (Figure 1).

Conclusions

In routine clinical care, NOACs (whether reduced or full dose) were associated with a lower risk of ischemic stroke, mortality and the composite endpoint, when compared to non-OAC use in high risk elderly AF patients at increased bleeding risk. Our findings provide complimentary “real world” data to support the generalizability of the results of ELDERCARE-AF trial into daily clinical practice.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Impacts of hemoglobin levels and platelet counts on clinical outcomes in patients with atrial fibrillation: oral anticoagulant use for patients with anemia and/or thrombocytopenia

Background

Hemoglobin (Hgb) levels and platelet (PLT) counts have beeen associated with adverse clinical outcomes in some patients with cardiovascular conditions. We aimed to assess the risks of clinical events among patients with atrial fibrillation (AF) in relation to Hgb levels and PLT counts. Second, we investigated clinical outcomes on warfarin or non-vitamin K antagonist oral anticoagulants (NOACs) compared to no oral anticoagulant use (non-OAC), in different Hgb and PLT strata.

Methods

We used medical data from a multi-center healthcare system in Taiwan which included 37,074 AF patients. Patients were categorized into 3 groups based on their Hgb levels and PLT counts: Group 1 (Hgb>10g/dL and PLT>100K/uL; n=29,147), Group 2 (Hgb<10g/dL or PLT<100K/uL; n=7,078) and Group 3 (Hgb<10g/dL and PLT<100K/uL; n=849). Patients in each category were further stratified as 3 groups according to their stroke prevention strategies; that is, non-OAC, warfarin or NOACs.

Results

A higher Hgb level and/or PLT count was associated with a higher risk of ischemic stroke/systemic embolism (IS/SE), but lower risks of intracranial hemorrhage (ICH) and major bleeding. The composite risks of IS/SE, ICH and major bleeding were higher in Group 3 or Group 2, compared to Group 1 (6.75%/yr versus 6.41%/yr versus 4.13%/yr). Compared to non-OACs, the use of warfarin was not associated with a lower composite risk of IS/SE, ICH and major bleeding in the 3 groups. NOACs were associated with a lower composite risk in Group 1 (aHR 0.68, 95% CI 0.60–0.76) and Group 2 (aHR 0.73, 95% CI 0.53–0.99), but was non-significant in Group 3 (aHR 0.73, 95% CI 0.17–3.07) (Figure). The net clinical benefits were consistently positive in different weight models, in favor of NOAC use, in Group 2 and its subgroups with either anemia or thrombocytopenia.

Conclusions

AF patients with anemia and/or thrombocytopenia were a high-risk population. Compared to no OAC use, NOACs were associated with significantly better clinical outcomes for patients with advanced anemia (Hgb<10g/dL) or thrombocytopenia (PLT<100K/uL), but not for those with both conditions. Harms or benefits of NOACs should be carefully evaluated and balanced in this population.

Funding Acknowledgement

Type of funding sources: None.

Pleckstrin homology domain-containing protein PHLDB3 supports cancer growth via a negative feedback loop involving p53

The tumour suppressor p53 transactivates the expression of its target genes to exert its functions. Here, we identify a pleckstrin homology domain-containing protein (PHLDB3)-encoding gene as a p53 target. PHLDB3 overexpression increases proliferation and restrains apoptosis of wild-type p53-harboring cancer cells by reducing p53 protein levels. PHLDB3 binds to MDM2 (mouse double minute 2 homolog) and facilitates MDM2-mediated ubiquitination and degradation of p53. Knockdown of PHLDB3 more efficiently inhibits the growth of mouse xenograft tumours derived from human colon cancer HCT116 cells that contain wild type p53 compared with p53-deficient HCT116 cells, and also sensitizes tumour cells to doxorubicin and 5-Fluorouracil. Analysis of cancer genomic databases reveals that PHLDB3 is amplified and/or highly expressed in numerous human cancers. Altogether, these results demonstrate that PHLDB3 promotes tumour growth by inactivating p53 in a negative feedback fashion and suggest PHLDB3 as a potential therapeutic target in various human cancers.

p53 is an oncosuppressor regulating several genes at the transcriptional level. Here, the authors identify a negative feedback loop between PHLDB3 and p53; PHLDB3 is a transcriptional target of p53 which facilitates MDM2-mediated p53 ubiquitination and degradation, impacting on tumorigenesis.

Poor-prognosis disclosure preference in cancer patient-caregiver dyads and its association with their quality of life and perceived stress: a cross-sectional survey in mainland China

BACKGROUND

This study attempted to examine the discordance between family caregivers and cancer patients in their poor-prognosis disclosure preferences in mainland China and then ascertained the associations between quality of life (QoL), perceived stress, and poor-prognosis disclosure preferences.

METHODS

Six hundred fifty-one pairs of inpatients and their matched caregivers (participation rate = 92.2%) were recruited in this cross-sectional survey. A set of paired self-administered questionnaires were completed independently by patient-caregiver dyads.

RESULTS

Fewer family caregivers than cancer patients felt that poor prognosis should be disclosed to patients (61.2% vs. 90.0%, p < 0.001). Patients' positive poor-prognosis disclosure preference was associated with patients' better QoL (p < 0.05) and caregivers' reduced perceived stress levels (p = 0.013). However, caregivers' poor-prognosis disclosure preference correlated only with their own physical state (p = 0.028). Moreover, the caregivers who concurred with patients in positive poor-prognosis disclosure preference were more likely to experience a better QoL (p < 0.05) and lower perceived stress levels (p = 0.048) in the III-IV stage subgroup.

CONCLUSIONS

There was a significant discrepancy in poor-prognosis disclosure preference between cancer patients and caregivers in China. The caregivers' preference of concealing poor prognosis from patients was not related to cancer patients' QoL or perceived stress. In addition, caregivers had better QoL and lower stress levels when they held the same positive poor-prognosis disclosure preference as the patients. Copyright © 2015 John Wiley & Sons, Ltd.

A percutaneous needle biopsy technique for sampling the supraclavicular brown adipose tissue depot of humans

Brown adipose tissue (BAT) has been proposed as a potential target tissue against obesity and its related metabolic complications. Although the molecular and functional characteristics of BAT have been intensively studied in rodents, only a small number of studies have used human BAT specimens due to the difficulty of sampling human BAT deposits. We established a novel positron emission tomography and computed tomography-guided Bergström needle biopsy technique to acquire human BAT specimens from the supraclavicular area in human subjects. Forty-three biopsies were performed on 23 participants. The procedure was tolerated well by the majority of participants. No major complications were noted. Numbness (9.6%) and hematoma (2.3%) were the two minor complications noted, which fully resolved. Thus, the proposed biopsy technique can be considered safe with only minimal risk of adverse events. Adoption of the proposed method is expected to increase the sampling of the supraclavicular BAT depot for research purposes so as to augment the scientific knowledge of the biology of human BAT.

Step trajectory analysis of spinal cord injured rats trained with neuromuscular electrical stimulation coordinated with robotic treadmill training

Applying neuromuscular electrical stimulation (NMES) during treadmill training (TT) has been shown to improve functional outcomes, such as gait speed and walking distance, in spinal cord injury (SCI) patients. However, ways to improve this combined NMES+TT therapy have not been investigated. We have developed NMES system for a rodent model of SCI to investigate whether and how more precisely timing the stimulation to robotically assisted hindlimb position might achieve rehabilitation of independent stepping after SCI. In our therapy (NMES+RTT), rodent ankle flexor muscles are stimulated while the hindlimbs are robotically driven through pre-programmed trajectories during treadmill training. The objectives of the work presented here were to quantify changes in step trajectory resulting from our combined NMES+RTT therapy and compare those effects with those induced by robotic treadmill training (RTT) alone. Animals were spinally contused to model severe SCI, and either received 2 weeks of NMES+RTT followed by 2 weeks of RTT (n=6) or 2 weeks of RTT followed by 2 weeks of NMES+RTT (n=7). Changes in step trajectories after training were analyzed. According to a deviation measure we developed, the step trajectories improved after either NMES+RTT or RTT training but more closely matched the desired pre-programmed trajectories after NMES+RTT than after RTT only. The step trajectories are also more consistent, as indicated by a coefficient of variation measure, after training and more so after NMES+RTT than after RTT only. These preliminary results from our NMES+RTT vs. RTT study are consistent with the hypothesis that appropriately timing NMES with hindlimb movements during stepping is an effective therapy for restoring the ability to step after spinal cord injury.

Knockdown of the Bcl-2 gene increases sensitivity to EGFR tyrosine kinase inhibitors in the H1975 lung cancer cell line harboring T790M mutation

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are being widely used as targeted therapy in non-small cell lung cancer (NSCLC), but most cases acquire drug-resistance in 9 months. However, the mechanisms of resistance are still not fully understood. Since it has been demonstrated that EGFR-TKI-mediated repression of downstream signaling cascades and apoptosis induction is a key mechanism through which EGFR-TKIs exert their cytotoxic effects, we reasoned that activation of downstream signaling pathways and changes in the expression of apoptosis-related proteins contribute to the acquired resistance to EGFR-TKIs. We analyzed the protein levels of p-Akt, Bcl-2, Bax between gefitinib-sensitive and gefitinib-resistant lung cancer cell lines and evaluated whether targeting the anti-apoptotic protein Bcl-2 induces cell apoptosis and further sensitizes resistant H1975 cells to gefitinib. The data showed that p-Akt was activated and accompanied by substantial Bcl-2 in the H1975 lung cancer cell line, whereas no evidence was observed in HCC827 cells. Using small interfering RNA (siRNA) to silence Bcl-2 in H1975 cells led to significant downregulation of Bcl-2 protein expression, decreased cell viability in vitro and induced intrinsic apoptosis confirmed by flow cytometry and PARP cleavage. In Bcl-2 siRNA-transfected cells, adding gefitinib further reduced the number of viable cells, induced apoptosis to a greater extent compared to either treatment alone. These preclinical data suggested that downregulation of Bcl-2 by RNAi in the gefitinib-resistant H1975 lung cancer cell line with T790M mutation enhanced the effects of gefitinib and may offer a novel therapeutic strategy for the treatment of NSCLC.

Caveolin-1 is involved in radiation-induced ERBB2 nuclear transport in breast cancer cells

This study examined the radiation-induced ERBB2 nuclear transport in the BT474 breast cancer cell line and the relationship between caveolin-1 and radiation-induced ERBB2 nuclear transport. The BT474 cells were treated with herceptin (200 nmol/L), PP2 (a caveolin-1 inhibitor, 100 nmol/L) and irradiation combined or alone. Confocal microscopy was used to observe the nuclear import of ERBB2 and caveolin-1 after irradiation. Western blotting was employed to detect the expression of ERBB2, caveolin-1 and DNA-PKcs after irradiation, and immunoprecipitation to identify the ERBB2 and caveolin-1 complex before perinuclear ERBB2 localization. Confocal microscopy showed the transport of ERBB2 and caveolin-1 from the cell membrane to the nucleus 15 min after irradiation and the proteins accumulated at the perinuclear region within 45 min. Western blotting revealed that the expression levels of ERBB2, caveolin-1 and DNA-PKcs were increased after irradiation and reached a peak 45 min later. Both herceptin and PP2 treatments were found to decrease ERBB2 expression. An immune complex composed of ERBB2 and caveolin-1 was found in the herceptin group after irradiation. It was concluded that after irradiation, ERBB2 may be transported from the cell membrane to the nucleus and activate DNA-PKcs to trigger DNA double-strand break (DSB) repair; caveolin-1 may participate in this process. Treatments involving the downregulation of caveolin-1 may increase the radiosensitization of breast cancer cells.

The CREB-miR-9 negative feedback minicircuitry coordinates the migration and proliferation of glioma cells

Migration-proliferation dichotomy is a common mechanism in gliomagenesis; however, an understanding of the exact molecular mechanism of this "go or grow" phenomenon remains largely incomplete. In the present study, we first found that microRNA-9 (miR-9) is highly expressed in glioma cells. MiR-9 inhibited the proliferation and promoted the migration of glioma cells by directly targeting cyclic AMP response element-binding protein (CREB) and neurofibromin 1 (NF1), respectively. Our data also suggested a migration-inhibitory role for CREB through directly regulating the transcription of NF1. Furthermore, we found that the transcription of miR-9-1 is under CREB's control, forming a negative feedback minicircuitry. Taken together, miR-9 inhibits proliferation but promotes migration, whereas CREB plays a pro-proliferative and anti-migratory role, suggesting that the CREB-miR-9 negative feedback minicircuitry plays a critical role in the determination of "go or grow" in glioma cells.

Effect of functional electrical stimulation (FES) combined with robotically assisted treadmill training on the EMG profile

Functional electrical stimulation (FES) is used to assist spinal cord injury patients during walking. However, FES has yet to be shown to have lasting effects on the underlying neurophysiology which lead to long-term rehabilitation. A new approach to FES has been developed by which stimulation is timed to robotically controlled movements in an attempt to promote long-term rehabilitation of walking. This approach was tested in a rodent model of spinal cord injury. Rats who received this FES therapy during a 2-week training period exhibited peak EMG activity during the appropriate phase of the gait cycle; whereas, rats who received stimulation which was randomly timed with respect to their motor activity exhibited no clear pattern in their EMG profile. These results from our newly developed FES system serve as a launching point for many future studies to test and understand the long-term effect of FES on spinal cord rehabilitation.

Efficacy and Safety Data of Taiwan Breast Cancer Patients Enrolled in the Lapatinib Expanded Access Program (LEAP)

Background: LEAP is a single-arm, open-label, expanded access study of lapatinib in combination with capecitabine in 42 countries. The primary objective of LEAP was to provide patients with pre-approval access to lapatinib based on positive clinical data from a pivotal Phase III trial.Methods: Enrolled patients had locally advanced or HER2 positive metastatic breast cancer (MBC), progressive disease (PD, by modified RECIST) following prior therapy with anthracycline-, taxane-, and trastuzumab-containing regimens, including some patients previously treated with capecitabine, and were ineligible for ongoing lapatinib trials. Patients received lapatinib (1250 mg/day) and capecitabine (2000 mg/m2/day, days 1-14, every 21 days). Baseline characteristics, including prior therapies, were collected. Response was assessed using RECIST criteria.Results: From Mar 2007 to Sep 2008, 238 patients were enrolled at 10 centers in Taiwan. At the 11 June 2009 data cut-off, data were collected and analyzed for 166 patients. Patients received an average of 5 prior cytotoxic therapies, including trastuzumab and capecitabine.Of 166 patients, 3 (2%) had complete response, 49 (30%) had partial response, 62 (37%) had stable disease, 42 (25%) had PD, and 10 (6%) were unknown. The median duration of treatment was 5.5 mo and the median time to progression was 5.3 mo, respectively. Per protocol, only serious adverse events (SAEs) were reported. Thirty SAEs were reported for 238 patients; 6 (20%) were considered treatment-related by investigators, were not fatal, and included stomatitis (2), vomiting (2), diarrhea (1), and cellulitis (1). As of 11 June 2009, 66 (40%) patients were alive and 149 withdrew from LEAP, the majority (85%) because of progressive disease.Conclusion: Although data were collected retrospectively via case report forms, these results reflect the real world setting in Taiwan for the treatment of erbB2+ MBC patients and confirms that lapatinib, in combination with capecitabine, demonstrates efficacy in this patient population including those who are heavily pretreated.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5093.

Phase IIb/III double-blind randomized trial of BIBW 2992, an irreversible, dual inhibitor of EGFR and HER2 plus best supportive care (BSC) versus placebo plus BSC in patients with NSCLC failing 1–2 lines of chemotherapy (CT) and erlotinib or gefitinib (LUX- Lung1): A preliminary report

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Background: No approved therapy exists for NSCLC patients (pts) who have failed chemotherapy (CT) and the reversible epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), erlotinib (E) or gefitinib (G). The efficacy of BIBW 2992 (Tovok), a potent, irreversible inhibitor of EGFR and human epidermal growth factor receptor 2 (HER2) with preclinical activity against the secondary resistance mutation T790M, in pts progressing after initial clinical benefit on E/G is being assessed in this randomized trial. Methods: Pts with advanced adenocarcinoma of the lung (Stage IIIB/IV; ECOG 0–2), who have failed one or two lines of CT (including platinum) and progressed following at least 12 weeks of E or G are randomized in a 2:1 ratio to receive BSC plus either oral BIBW 2992 50 mg qd or placebo until disease progression or unacceptable toxicity. Primary endpoint is overall survival, with progression-free survival, objective response and clinical benefit rate and duration, safety and quality of life being secondary endpoints. Enrollment of 400 pts is planned (HR=0.70, 85% power). An unblinded interim analysis of tumor response and safety by the independent Data Monitoring Committee (DMC) after the first 40 evaluable pts treated with BIBW 2992 will determine continuation to full accrual. Results: From May to November 2008, 145 pts have been randomized and 76 are still on treatment. Demographics (n=145): median age 59 (range: 30–82); female 68%, current/ex-smokers 38%; metastatic disease 91%, ECOG 0–1 92%; Asian origin 68%. 50% had one prior line of CT. Main prior EGFR-TKI was G in Asians (70%) and E in non-Asians (85%). 40% of pts had achieved a PR or CR on previous treatment with E/G. Duration of prior E/G treatment was >24 weeks and >48 weeks in 80% and 40% of pts, respectively. As expected, diarrhea, rash, anorexia, stomatitis, paronychia, nausea and vomiting were the most frequently observed adverse events. Conclusions: The trial is continuing recruitment after DMC review of efficacy and safety and updated demographics and blinded safety data will be reported.

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MicroRNA-21 down-regulates the expression of tumor suppressor PDCD4 in human glioblastoma cell T98G

MicroRNAs have been linked to different cancer-related processes. The microRNA miR-21 appears to function as an anti-apoptosis factor in glioblastomas. However, the functional target genes of miR-21 are largely unknown in glioblastomas. In this study, bioinformatics analysis was used to identify miR-21 target sites in various genes. Luciferase activity assay showed that a number of genes involved in apoptosis, PDCD4, MTAP, and SOX5, carry putative miR-21 binding sites. Expression of PDCD4 protein correlates inversely with expression of miR-21 in a number of human glioblastoma cell lines such as T98G, A172, U87, and U251. Inhibition of miR-21 increases endogenous levels of PDCD4 in cell line T98G and over-expression miR-21 inhibits PDCD4-dependent apoptosis. Together, these results indicate that miR-21 expression plays a key role in regulating cellular processes in glioblastomas and may serve as a target for effective therapies.

MicroRNA-128 inhibits glioma cells proliferation by targeting transcription factor E2F3a

MicroRNAs are approximately 21nt single-stranded RNAs and function as regulators of gene expression. Previous studies have shown that microRNAs play crucial roles in tumorigenesis by targeting the mRNAs of oncogenes or tumor suppressors. Here we show that brain-enriched miR-128 is down-regulated in glioma tissues and cell lines when compared to normal brain tissues. Overexpression of miR-128 in glioma cells inhibited cell proliferation. A bioinformatics search revealed a conserved target site within the 3'untranslated region (UTR) of E2F3a, a transcription factor that regulates cell cycle progression. The protein levels of E2F3a in gliomas and normal brain tissues were negatively correlated to the expression levels of miR-128 in these tissues. Overexpression of miR-128 suppressed a luciferase-reporter containing the E2F3a-3'UTR and reduced the level of E2F3a protein in T98G cells. Moreover, knocking down of E2F3a had similar effect as overexpression of miR-128, and overexpression of E2F3a can partly rescue the proliferation inhibition caused by miR-128. Taken together, our study demonstrates that miR-128 can inhibit proliferation of glioma cells through one of its targets, E2F3a.

Improving the prediction of human microRNA target genes by using ensemble algorithm

MicroRNAs are a class of small endogenous noncoding RNAs which play important regulatory roles mainly by post-transcriptional depression. Finding miRNA target genes will help a lot to understand their biological functions. We developed an ensemble machine learning algorithm which helps to improve the prediction of miRNA targets. The performance was evaluated in the training set and in FMRP associated mRNAs. Moreover, using human mir-9 as a test case, our classification was validated in 9 of 15 transcripts tested. Finally, we applied our algorithm on the whole prediction data set provided by miRanda website. The results are available at http://www.biosino.org/~kanghu/mRTP/mRTP.html.