Jiang, Wen

AbstractBackgroundA recent phase III trial (NCT01372774) comparing use of stereotactic radiosurgery [SRS] versus whole-brain radiation therapy [WBRT] after surgical resection of a single brain metastasis revealed that declines in cognitive function were more common with WBRT than with SRS. A secondary endpoint in that trial, and the primary objective in this secondary analysis, was to identify baseline biomarkers associated with cognitive impairment after either form of radiotherapy for brain metastasis. Here we report our findings on APOE genotype and serum levels of associated proteins and their association with radiation-induced neurocognitive decline.MethodsIn this retrospective analysis of prospectively collected samples from a completed randomized clinical trial, patients provided blood samples every 3 months that were tested by genotyping and enzyme-linked immunosorbent assay, and results were analyzed in association with cognitive impairment.ResultsThe APOE genotype was not associated with neurocognitive impairment at 3 months. However, low serum levels of ApoJ, ApoE, or ApoA protein (all P < .01) and higher amyloid beta (Aβ 1–42) levels (P = .048) at baseline indicated a greater likelihood of neurocognitive decline at 3 months after SRS, whereas lower ApoJ levels were associated with decline after WBRT (P = .014).ConclusionsPatients with these pretreatment serum markers should be counseled about radiation-related neurocognitive decline.

AbstractA major challenge in the development of cancer nanomedicine is the inability for nanomaterials to efficiently penetrate and deliver therapeutic agents into solid tumors. Previous studies have shown that tumor vasculature and extracellular matrix regulate the transvascular and interstitial transport of nanoparticles, both critical for successfully delivering nanomedicine into solid tumors. Within the malignant tumor microenvironment, blood vessels are morphologically abnormal and functionally exhibit substantial permeability. Furthermore, the tumor extracellular matrix (ECM), unlike that of the normal tissue parenchyma, is densely packed with collagen. These pathophysiological properties greatly impede intratumoral delivery of nanomaterials. By using an antivascular endothelial growth factor receptor antibody, DC101, and an antitransforming growth factor β1 (TGF‐β1) antibody, normalization of the tumor vasculature and ECM is achieved, respectively, in a syngeneic murine glioma model. This normalization effect results in a more organized vascular network, improves tissue perfusion, and reduces collagen density, all of which contribute to enhanced nanoparticle delivery and distribution within tumors. These findings suggest that combined vascular and ECM normalization strategies can be used to remodel the tumor microenvironment and improve nanomedicine delivery into solid tumors, which has significant implications for developing more effective combinational therapeutic strategies using cancer nanomedicine.

Abstract The clinical success of immune checkpoint inhibitors in treating metastatic and refractory cancers has generated significant interest in investigating their role in treating locally advanced diseases, thus requiring them to be combined with standard treatments in the hope of producing synergistic antitumor responses. Radiotherapy, in particular, has long been hypothesized to have actions complementary to those of immune checkpoint blockade, and a growing body of evidence indicates that cancer immunotherapy may also have radiosensitizing effects, which would provide unique benefit for locoregional treatments. Recent studies have demonstrated that when immune cells are activated by immunotherapeutics, they can reprogram the tumor microenvironment in ways that may potentially increase the radiosensitivity of the tumor. In this review, we highlight the evidence that supports reciprocal interactions between cancer immunotherapy and radiotherapy, where in addition to the traditional notion that radiation serves to enhance the activation of antitumor immunity, an alternative scenario also exists in which T-cell activation by cancer immunotherapy may sensitize tumors to radiation treatment through mechanisms that include normalization of the tumor vasculature and tissue hypoxia. We describe the empirical observations from preclinical models that support such effects and discuss their implications for future research and trial design.

Ischemic injuries and local hypoxia can result in osteocytes dysfunction and play a key role in the pathogenesis of avascular osteonecrosis. Conventional imaging techniques including magnetic resonance imaging (MRI) and computed tomography (CT) can reveal structural and functional changes within bony anatomy; however, characterization of osteocyte behavioral dynamics in the setting of osteonecrosis at the single cell resolution is limited. Here, we demonstrate an optical approach to study real-time osteocyte functions in vivo. Using nicotinamide adenine dinucleotide (NADH) as a biomarker for metabolic dynamics in osteocytes, we showed that NADH level within osteocytes transiently increase significantly after local ischemia through non-invasive photo-induced thrombosis of afferent arterioles followed by a steady decline. Our study presents a non-invasive optical approach to study osteocyte behavior through the modulation of local environmental conditions. Thus it provides a powerful toolkit to study cellular processes involved in bone pathologies in vivo.

Abstract Glioma stem cells (GSC) and epithelial–mesenchymal transition (EMT) are strongly associated with therapy resistance and tumor recurrence, but the underlying mechanisms are incompletely understood. Here, we show that S100A4 is a novel biomarker of GSCs. S100A4+ cells in gliomas are enriched with cancer cells that have tumor-initiating and sphere-forming abilities, with the majority located in perivascular niches where GSCs are found. Selective ablation of S100A4-expressing cells was sufficient to block tumor growth in vitro and in vivo. We also identified S100A4 as a critical regulator of GSC self-renewal in mouse and patient-derived glioma tumorspheres. In contrast with previous reports of S100A4 as a reporter of EMT, we discovered that S100A4 is an upstream regulator of the master EMT regulators SNAIL2 and ZEB along with other mesenchymal transition regulators in glioblastoma. Overall, our results establish S100A4 as a central node in a molecular network that controls stemness and EMT in glioblastoma, suggesting S100A4 as a candidate therapeutic target. Cancer Res; 77(19); 5360–73. ©2017 AACR.

AbstractBackgroundOverexpression of p16 is associated with improved outcomes among patients with oropharyngeal carcinoma. However, its role in the outcomes of patients with nasopharyngeal cancer (NPC) remains unclear.MethodsEighty‐six patients with NPC treated at MD Anderson Cancer Center from 2000 to 2014 were identified. Epstein‐Barr virus (EBV) and human papillomavirus (HPV) status were determined by in situ hybridization (ISH) and p16 by immunohistochemical staining.ResultsEBV positivity was associated with extended overall survival (OS; median, 95.0 vs 44.9 months; p < .004), progression‐free survival (PFS; median, 80.4 vs 28.1 months; p < .013), and locoregional control (median, 104.4 vs 65.5 months; p < .043). In patients with EBV‐positive tumors, p16 overexpression correlated with improved PFS (median, 106.3 vs 27.1 months; p < .02) and locoregional control (median, 93.6 vs 64.5 months; p < .02).ConclusionP16 overexpression is associated with improved PFS and locoregional control in patients with EBV‐positive NPC. P16 expression may complement EBV status in predicting treatment outcomes for patients with NPC. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1459–E1466, 2016

Abstract Introduction Recent advances in stereotactic radiosurgery (SRS) have improved clinical outcomes in patients with limited intracranial metastases. As a result of this high-dose radiation delivery to a focal area within the brain, tissue structural and functional changes within the treatment field are often difficult to distinguish from local tumor recurrence based on conventional imaging techniques. Here, we demonstrate that elevation of circulating cells of myeloid origin, the key regulators of inflammation and immune responses, can serve as a potential surrogate marker to differentiate radiation-induced tissues changes from local tumor recurrence. Materials and Methods We retrospectively identified 96 patients who were initially treated with Gamma-knife radiosurgery at MD Anderson Cancer Center from 2009-2013 for brain metastases, and subsequently underwent surgical resection of previous irradiated lesions after presenting with clinical symptoms and radiographic findings suggestive of tumor progression. All surgical specimens were centrally reviewed by neuropathology. Pre-operative circulating blood cell profiles were analyzed for monocytic, granulocytic and lymphocytic sub-populations. Results A total of 11 and 85 patients who underwent surgical resection after prior SRS for brain metastasis were pathologically confirmed to have radiation-induced changes or tumor recurrence, respectively. Among patients with confirmed recurrence vs. those with radiation-induced changes, the number of circulating immature granulocytes (mean = 0.093 × 103ul−1 vs 0.032 × 103ul−1, p = 0.075) and monocytes (mean = 0.632 × 103ul−1 vs 0.401 × 103ul−1, p = 0.007) were elevated when compared to patients with radiation-induced changes (combined: mean = 0.71 × 103ul−1 vs 0.43 × 103ul−1, p = 0.002). No statistically significant differences were observed among mature granulocytic or lymphocytic populations between the two groups. Receiver operating characteristic analysis showed significant discriminative utility of pre-operative myeloid cell count when compared to reference line of no discrimination (AUC = 0.774, p = 0.003). The cut-point for myeloid cell population was found be &gt; = 0.5 × 103ul−1, which corresponds to a detection sensitivity of 73.3% and specificity of 72.7% for tumor recurrence. Conclusion Bone marrow cells of myeloid origin play important roles in mediate acute inflammatory reactions and in regulating adaptive immunity. We showed here that certain primitive cells of myeloid lineage may potentially be used to aid the differentiation of tumor recurrence from radiation-induced changes in patients who had SRS for brain metastasis. The identification of potential circulating biomarkers that can complement traditional imaging to distinguish the two distinct pathological entities has significant implications in the management of these patients. Note: This abstract was not presented at the meeting. Citation Format: Wen Jiang, Yvo Rodriguez, Nicolas S. Boehling, Sujit S. Prabhu, Betty Y.S. Kim, Patrick Hwu, Erik P. Sulman, Paul D. Brown, Jing Li. Circulating myeloid precursor profile as potential marker to differentiate radiation changes from tumor recurrence after brain stereotactic radiosurgery. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 532. doi:10.1158/1538-7445.AM2015-532