Targeting Immunosuppressive Myeloid Cells and Exhausted CD8+ T Cells Overcomes Radioresistance in NSCLC

PURPOSE/OBJECTIVE(S)

Although stereotactic body radiation therapy (SBRT) has achieved great success in the treatment of non-small cell lung cancer (NSCLC), local relapses still occur and abscopal effects are rarely seen even when combined with immune checkpoint blockers (ICBs). Therefore, it is necessary to thoroughly understand the immune responses after SBRT.

MATERIALS/METHODS

We characterized the dynamic changes of tumor-infiltrating immune cells at early and late time points after SBRT in a therapy-resistant murine tumor model using single-cell transcriptomes and T-cell receptor sequencing.

RESULTS

At the early stage, the innate and adaptive immune systems were activated, including activation of NKs and NKTs, and infiltration of cytotoxic CD8+ T cells. At the late stage, however, the tumor immune microenvironment (TIME) shifted into immunosuppressive properties, containing enrichment of immunosuppressive tumor-associated neutrophils (TANs), M2-like tumor-associated macrophages (TAMs), and terminal exhausted CD8+ T cells. Furthermore, our study revealed that inhibition of CD39 combined with SBRT preferentially reinvigorated exhausted CD8+ T cells and promoted their proliferation, infiltration, and cytotoxicity. Meanwhile, it also promoted M1-like macrophage infiltration and DCs maturation. On the other hand, consequently increased infiltration of immunosuppressive myeloid cells after SBRT could be a potential mechanism mediating CD8+ T cell dysfunction. Moreover, we found that combination treatment with anti-VISTA and SBRT synergistically reduced immunosuppressive myeloid cells, containing TANs, M-MDSCs, and M2-like TAMs, and further activated CD8+ T cells. Clinically, high VISTA expression was associated with poor prognosis in NSCLC patients.

CONCLUSION

Altogether, our data provides deep insight into acquired resistance to SBRT from an immune perspective and presents rational combination strategies.

CaFeFeNbO6 - an iron-based double double perovskite

Ordering of cations is important for controlling properties of ABO₃ perovskites, and CaFeFeNbO₆ is the first example of an Fe-based AA'BB'O₆ double double perovskite, with Ca²⁺/Fe²⁺ ordered on A-site columns, and Fe³⁺/Nb⁵⁺ at the octahedral B-sites. Substantial (37%) antisite disorder of the latter cations leads to spin glassy magnetism below a freezing transition at 12 K. The CaMnFeNbO₆ analogue also shows substantial cation disorder and spin glassy behaviour. Comparison of synthesis pressures for ordered materials based on different A-site transition metals, suggests that pressures of at least 14-18 GPa will be required to discover the expected plethora of double double perovskites based on A' cations smaller than Mn²⁺.

Clinical features and cardiovascular magnetic resonance characteristics in Danon disease

AIMS

To investigate the clinical spectrum, cardiovascular magnetic resonance imaging (cMRI) characteristics, including T1 and extracellular volume fraction, and outcomes of Danon disease to facilitate further understanding of the phenotype of patients with Danon disease.

MATERIALS AND METHODS

The study comprised six male patients 8-23 years old recruited to the study between 2014-2019. The clinical presentation, laboratory examinations, pathology/genetic analysis, electrocardiography (ECG), echocardiography, and cCMRI characteristics were summarised.

RESULTS

Five out of six patients suffered from hypertrophic cardiomyopathy (HCM) phenotype of Danon disease, while one patient had dilated cardiomyopathy (DCM) phenotype. Left ventricular (LV) and left atrial (LA) function were impaired at strain measurement. Diffuse and focal late gadolinium enhancement (LGE) were observed separately in the LV walls of three patients and right ventricular (RV) insertion points of the remaining three patients. Furthermore, values for the native T1 (mean 1313.3 ms) and extracellular volume fraction (ECV; mean 39.17%) of three patients were increased.

CONCLUSIONS

Both dilated and hypertrophic cardiomyopathy may be the phenotypes of Danon disease. Comprehensive cCMRI played a unique role in the diagnosis and grading severity and risk factors of Danon disease in vivo, especially by using robust quantitative strain analysis, T1 mapping, and further ECV calculation.

Clinical use of internal distraction osteogenesis in the rehabilitation of gunshot injuries of the mandible

Rehabilitation of gunshot injuries that require combined reconstruction of bone and soft tissue poses a considerable challenge. We describe three cases of rehabilitation for mandibular defects and deformities caused by gunshot injuries. After debridement, three kinds of internal distractors were used. The bony transport discs were distracted about 10-22mm, and the new bone formed well in the distracted gaps. There was no evidence of infection during the consolidation period or follow up. Aesthetic appearance was also pleasing after treatment. Internal distraction osteogenesis after debridement might be a practical way of synchronously reconstructing bony and soft tissue after mandibular gunshot injuries.

Autophagy attenuates the oxidative stress-induced apoptosis of Mc3T3-E1 osteoblasts

OBJECTIVE

The oxidative stress-induced osteoblast apoptosis plays an important role in the pathological process of osteoporosis, but the roles of autophagy in oxidative stress and apoptosis of osteoblasts remain unclear. This study aimed to observe the role of autophagy in oxidative stress injury of osteoblasts and the relationship between autophagy and apoptosis.

MATERIALS AND METHODS

Mc3T3-E1 cells were stimulated with different concentrations (0.1, 0.5, and 1 mM) of hydrogen peroxide. The cell viability was detected via cell counting kit 8 (CCK8) at different time points (0, 2, 6, 8, and 12 h), the apoptosis was detected via Western blotting and flow cytometry, and the autophagy was detected via macrophage-derived chemokine (MDC) and transmission electron microscope. The changes in expression of autophagy-associated protein, Beclin1, and LC3II/I ratio, were detected via Western blotting. Moreover, the intracellular reactive oxygen species (ROS) level and extracellular superoxide dismutase (SOD) level were observed using the autophagy regulators, rapamycin (Rap) and 3-methyladenine (3-MA), so as to clarify the interaction between autophagy and cellular oxidation.

RESULTS

Hydrogen peroxide-induced apoptosis and autophagy of osteoblasts were in dose- and time-dependent manners; the hydrogen peroxide inhibitors could inhibit the autophagy level, and autophagy inhibitor (3-MA) could significantly enhance the hydrogen peroxide-induced ROS level and apoptosis rate in cells. Besides, Western blotting confirmed that the cleaved caspase-3 and cleaved poly adenosine diphosphate ribose polymerase (PARP) proteins were increased. The autophagy inducer (Rap) partially inhibited the hydrogen peroxide-induced oxidative stress and apoptosis.

CONCLUSIONS

Autophagy inhibits the oxidative stress-mediated apoptosis of osteoblasts, which is a potential target for the osteoporosis treatment.

[Clinicopathological and molecular characteristics of Epstein-Barr virus associated gastric cancer: a single center large sample case investigation]

OBJECTIVE

Epstein-Barr virus associated gastric cancer (EBVaGC) is different from the traditional gastric cancer (Epstein-Barr virus non-associated gastric cancer, EBVnGC), and has unique clinicopathological features. This study investigated the largest single center cancer series so as to establish the clinicopathological and molecular characteristics of EBVaGC in China.

METHODS

A retrospective analysis was conducted on EBVaGC and EBVnGC patients diagnosed at Peking University Cancer Hospital from 2003 to 2018 by comparing their clinicopathological features and prognosis. The gastric cancer (GC) dataset of public database was analyzed to obtain differentially expressed genes. The expression of important genes and their association with prognosis of GC were verified in GC tissues from our hospital.

RESULTS

In this study, 3 241 GC patients were included, and a total of 163 EBVaGC (5.0%) patients were identified. Compared with EBVnGC, EBVaGC was higher in male and younger patients, and positively associated with remnant GC, poorly differentiated adenocarcinoma, and mixed type GC. EBVaGC was inversely related to lymph node metastasis. The 5-year survival rate of EBVnGC and EBVaGC was 59.6% and 63.2% respectively (P<0.05). In order to explore molecular features of EBVaGC, the Cancer Genome Atlas (TCGA) dataset was analyzed (n=240), and 7 404 significant differentially expressed genes were obtained, involving cell proliferation, apoptosis, invasion and metastasis. The down-regulated invasion/metastasis gene SALL4 and the up-regulated immune checkpoint gene PD-L1 were important molecular features of EBVaGC. Validation of these two genes in large GC series showed that the majority of the EBVaGC was SALL4 negative (1/92, 1.1%, lower than EBVnGC, 303/1 727, 17.5%), and that PD-L1 was mostly positive in EBVaGC (81/110, 73.6%, higher than EBVnGC, 649/2 350, 27.6%). GC patients with SALL4 negative and PD-L1 positive were often associated with better prognosis.

CONCLUSION

EBVaGC is a unique subtype of GC with less metastasis and a good prognosis. It also has a distinct molecular background. The down-regulation of invasion/metastasis gene SALL4 and up-regulation of immune checkpoint gene PD-L1 are important molecular features.

Identification of a novel microRNA important for melanogenesis in alpaca (Vicugna pacos)

The molecular mechanisms underlying the formation of coat colors in animals are poorly understood. Recent studies have demonstrated that microRNA play important roles in the control of melanogenesis and coat color in mammals. In a previous study, we characterized the miRNA expression profiles in alpaca skin with brown and white coat color and identified a novel miRNA (named lpa-miR-nov-66) that is expressed significantly higher in white skin compared to brown skin. The present study was conducted to determine the functional roles of this novel miRNA in the regulation of melanogenesis in alpaca melanocytes. lpa-miR-nov-66 is predicted to target the soluble guanylate cyclase (sGC) gene based on presence of a binding site in the sGC coding sequence (CDS). Overexpression of lpa-miR-nov-66 in alpaca melanocyes upregulated the expression of sGC both at the mRNA and protein level. Overexpression of lpa-miR-nov-66 in melanocyes also resulted in decreased expression of key melanogenic genes including tyrosinase (TYR), tyrosinase related protein 1 (TYRP1), and microphthalmia transcription factor (MITF). Our ELISA assays showed increased cyclic guanosine monophosphate (cGMP) but decreased cyclic adenosine monophosphate (cAMP) production in melanocytes overexpressing lpa-miR-nov-66. In addition, overexpression of lpa-miR-nov-66 also reduced melanin production in cultured melanocytes. Results support a role of lpa-miR-nov-66 in melanocytes by directly or indirectly targeting , which regulates melanogenesis via the cAMP pathway.

Simultaneous integrated boost intensity-modulated radiotherapy for treatment of locally advanced non-small-cell lung cancer: a retrospective clinical study

OBJECTIVE

To evaluate the clinical efficacy and safety of simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) for patients with locally advanced non-small-cell lung cancer (LANSCLC).

METHODS

48 patients with LANSCLC treated with SIB-IMRT from January 2010 to April 2012 were retrospectively analysed. A radiation dose of 45-63 Gy (median dose, 51.58 Gy) was delivered to the planning target volume (1.8-2.0 Gy daily fractions) simultaneously with 55.0-74.2 Gy (median dose, 63 Gy) to the planning gross tumour volume (2.00-2.25 Gy daily fractions). 45 patients received concurrent/sequential chemotherapy. The overall survival (OS), locoregional recurrence-free survival (LRFS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method. Treatment-related pneumonitis and oesophagitis were graded according to the Common Terminology Criteria for Adverse Events v. 4.0.

RESULTS

By 1 July 2013, 29 of the 48 patients were dead. The median follow-up time for the survivors was 28 months (19-44 months). The median OS and PFS were 21 and 14 months, respectively. The median LRFS time was not reached. The 2-year LRFS, OS and PFS were 62.5%, 45.1% and 28.0%, respectively. Two patients experienced Grade 3 treatment-related pneumonitis, two patients experienced Grade 5 treatment-related pneumonitis and two patients had ≥Grade 3 oesophagitis.

CONCLUSION

SIB-IMRT appears to be an effective therapeutic option in patients with LANSCLC and warrants further evaluation with increased number of patients in prospective clinical trials.

ADVANCES IN KNOWLEDGE

This study explores the feasibility of delivering tumoricidal doses of radiation to primary lesions in non-small-cell lung cancer.

Death-associated protein-3, DAP-3, correlates with preoperative chemotherapy effectiveness and prognosis of gastric cancer patients following perioperative chemotherapy and radical gastrectomy

Background:

DAP3 is a member of the death-associated protein (DAP) family and is characterised by proapoptotic function. It is involved in both exogenous and endogenous apoptotic pathways. In our previous studies, apoptotic level was found to be correlated with the effectiveness of preoperative chemotherapy. The effectiveness of preoperative chemotherapy was also associated with the overall effectiveness of the combined therapy and prognosis. The present study aimed to investigate the role of DAP3 in the evaluation of preoperative chemotherapy effectiveness and its ability to predict prognosis in gastric cancer.

Methods:

Quantitative PCR and immunohistochemistry staining were performed in 87 patients who received combined therapy. Knockdown of DAP3 was conducted in gastric cancer cell lines to investigate its impact on cell growth, migration, adhesion and invasion. Tolerance to chemotherapy agents was determined by assessing apoptosis and caspase-3.

Results:

Higher DAP3 expression in gastric tumours was correlated with better prognosis. Knockdown of DAP3 expression promoted cell migration and enhanced resistance to chemotherapy by inhibiting apoptosis.

Conclusion:

DAP3 is a potential molecular marker for response to preoperative chemotherapy and for predicting prognosis in gastric cancer patients treated with neoadjuvant chemotherapy and gastrectomy.

Periodontal tissue engineering with stem cells from the periodontal ligament of human retained deciduous teeth

BACKGROUND AND OBJECTIVE

Periodontal ligament stem cells from human permanent teeth (PePDLSCs) have been investigated extensively in periodontal tissue engineering and regeneration. However, little knowledge is available on the periodontal ligament stem cells from human retained deciduous teeth (DePDLSCs). This study evaluated the potential of DePDLSCs in periodontal tissue regeneration.

MATERIAL AND METHODS

DePDLSCs were isolated and purified by limited dilution. The characteristics of DePDLSCs were evaluated and compared with PePDLSCs both in vitro and in vivo.

RESULTS

DePDLSCs presented a higher proliferation rate and colony-forming capacity than PePDLSCs in vitro. During the osteogenic induction, alkaline phosphatase (ALP) activity, mineralized matrix formation and expression of mineralization-related genes, including runt-related transcription factor 2 (RUNX2), ALP, collagen type I (COLI) and osteocalcin (OCN) were significantly enhanced in DePDLSCs compared with PePDLSCs. Furthermore, DePDLSC cell sheets showed a stronger synthesis of collagen type I in the extracellular matrix than did PePDLSC cell sheets. After in vivo transplantation, DePDLSC cell sheets recombined with human dentin blocks were able to generate new cementum/periodontal ligament-like tissues.

CONCLUSION

Our findings suggest that DePDLSCs can be used as a promising candidate for periodontal tissue engineering.

Targeted therapy via oral administration of attenuated Salmonella expression plasmid-vectored Stat3-shRNA cures orthotopically transplanted mouse HCC

The development of RNA interference-based cancer gene therapies has been delayed due to the lack of effective tumor-targeting delivery systems. Attenuated Salmonella enterica serovar Typhimurium (S. Typhimurium) has a natural tropism for solid tumors. We report here the use of attenuated S. Typhimurium as a vector to deliver shRNA directly into tumor cells. Constitutively activated signal transducer and activator of transcription 3 (Stat3) is a key transcription factor involved in both hepatocellular carcinoma (HCC) growth and metastasis. In this study, attenuated S. Typhimurium was capable of delivering shRNA-expressing vectors to the targeted cancer cells and inducing RNA interference in vivo. More importantly, a single oral dose of attenuated S. Typhimurium carrying shRNA-expressing vectors targeting Stat3 induced remarkably delayed and reduced HCC (in 70% of mice). Cancer in these cured mice did not recur over 2 years following treatment. These data demonstrated that RNA interference combined with Salmonella as a delivery system may offer a novel clinical approach for cancer gene therapy.

[Zero-stress state of renal artery in spontaneously hypertensive rats]

By observing the opening angle of the renal artery, the zero-stress state of the renal artery was studied in spontaneously hypertensive rats (SHR) prior to and posterior to their hypertension, and the role of endogenous angiotensin II (Ang II) and endothelin (ET) on the zero-stress state was studied by giving SHR Losartan(AT1 receptor antagonist of Ang II) and BMS-182874 (an A type receptor antagonist of ET) respectively. The opening angle of the renal artery in SHR with established hypertension was much greater than that in wistar-Kyoto rats(WKY) (114.2 +/- 42.2 vs 70.2 +/- 30.4, P < 0.01). The opening angles of the renal artery in SHR treated with Losartan and BMS-182874 were much smaller than those in control SHR. The opening angles of the renal artery in Losartan-treated and BMS-182874-treated SHR were 65.9 +/- 32.7 and 66.6 +/- 41.54 respectively. The results suggest that non-unequal growth exists in the renal arterial wall in SHR with established hypertension and the residual stress and strain in SHR are greater than those in age-matched WKY. Endogenous Ang II and ET may play a role in the changes of zero-stress state in SHR with hypertension.

[Remodeling and biomechanical properties of thoracic aorta in spontaneously hypertensive rats]

Morphometry and microstructure of thoracic aorta of spontaneously hypertensive rats (SHR) at different periods before and after hypertension were studied quantitatively by histological method and computer image analysis. We also observed the changes of opening angle in the zero-stress state and the relationship between pressure and diameter in SHR during established hypertension. The results showed that with blood pressure chronically increasing, there was a significant increase in morphometric parameters and microstructure parameters of the thoracic aorta in SHR. The zero-stress state of opening angle in SHR during established hypertension increased significantly. These reults suggest that aortic structural remodeling in hypertension such as thickness of vascular wall and disproportional increase of collagen may lead to decrease in distensibility of the aorta in SHR. The structural remodeling and changes of mechanical properties in aorta may contribute to the important pathophysiology of hypertension-induced complications.

[Sequencing and analysis of the NS5 region of HGV/GBV-C gene]

To study the genomic organization of non structural region 5 of HGV in China, 186 nucleotides of NS5 region of HGV were amplified, cloned and sequenced. The data were analyzed with computer programs. The results indicated that the gene sequence homology between 2 HGV isolates in this study was 95.2%. The comparison of these 2 isolates and 3 foreign isolates reported previously showed that the sequence homology was in the range of 84.4% to 92.4%, and was obvious by divergent from the foreign isolates. The results make us consider that HGV may have different genotypes, after a further inspection into the gene sequence of each region of HGV. The 2 isolates were from the sera collected in 1984, therefore the existence of HGV infection in Harbin was retrospectively traced to 1980s.

Computerized case-based instructional system for computed tomography and magnetic resonance imaging of brain tumors

RATIONALE AND OBJECTIVES

A computerized system that applies the case-based approach to training radiologists to diagnose brain tumors was designed. The authors attempted to provide residents a tool that supports their visual memory and inducts case-based reasoning.

METHODS

A relational database with a digital image library was implemented and incorporated into a computer aided instruction environment based on case presentation. An indexing system was structured around case features (case history and radiologic findings). "If-then" type rules were used to control the search direction within the case library and to generate lists of diagnostic hypotheses. The indexing system was evaluated against cases "known" to the system.

RESULTS

The current case library consists of 122 cases with 640 digitized images (computed tomography and magnetic resonance imaging). The accuracy of retrieval for "known" to the system cases was 80.7%.

CONCLUSIONS

A case library stored on a personal computer can be efficiently searched for a combination of radiologic findings and can offer quality images for comparison to the case in question. A case library is a source of the information that may be used by different teaching applications.