Posterior Uveitis Associated with Cemiplimab.

PURPOSE: The immune checkpoint inhibitors (ICPIs) comprise a class of oncologic immunotherapies. The most recent US Food and Drug Administration-approved ICPI is cemiplimab (Libtayo®). Cemiplimab, like the other ICPIs, blocks checkpoint receptors in order to disinhibit T-cells so that they may detect and eliminate tumor cells. Consequently, treatment with ICPIs is associated with immune-related adverse events including uveitis. METHODS: Case report. RESULTS: A 63-year-old man with a history of metastatic squamous cell carcinoma developed blurry vision 3 months after starting treatment with cemiplimab. The patient was found to have posterior uveitis with retinal vasculitis that was successfully controlled with discontinuation of the medication as well as treatment with local and systemic steroids. CONCLUSION: Similar to other ICPIs, uveitis may be associated with cemiplimab. In the setting of posterior uveitis, treatment may require cessation of cemiplimab and intensive steroid treatment.

Inflammasome Proteins in Serum and Serum-Derived Extracellular Vesicles as Biomarkers of Stroke.

The inflammasome is a key contributor to the inflammatory innate immune response after stroke. We have previously shown that inflammasome proteins are released in extracellular vesicles (EV) after brain and spinal cord injury. In addition, we have shown that inflammasome proteins offer great promise as biomarkers of central nervous system (CNS) injury following brain trauma. In the present study, we used a Simple Plex Assay (Protein Simple), a novel multi-analyte automated microfluidic immunoassay platform, to analyze serum and serum-derived EV samples from stroke patients and control subjects for inflammasome protein levels of caspase-1, apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC), Interleukins (IL)-1ß, and (IL)-18. Receiver operator characteristic (ROC) curves with associated confidence intervals obtained from the analysis of serum samples revealed that the area under the curve (AUC) for ASC was 0.99 with a confidence interval between 0.9914 and 1.004, whereas the AUC for caspase-1, IL-1ß, and IL-18 were 0.75, 0.61, and 0.67, respectively. Thus, these data indicate that ASC is a potential biomarker of stroke and highlight the role of the inflammasome in the inflammatory response after brain ischemia.

Traumatic Brain Injury-Induced Acute Lung Injury: Evidence for Activation and Inhibition of a Neural-Respiratory-Inflammasome Axis.

Approximately 20-25% of traumatic brain injury (TBI) subjects develop acute lung injury (ALI), but the pathomechanisms of TBI-induced ALI remain poorly defined. Our previous work has shown that the inflammasome plays a critical role in TBI-induced secondary pathophysiology and that inflammasome proteins are released in extracellular vesicles (EV) after TBI. Here we investigated whether EV-mediated inflammasome signaling contributed to the etiology of TBI-induced ALI. C57/BL6 male mice were subjected to controlled cortical impact (CCI), and the brains and lungs were examined for inflammasome activation and ALI at 4 and 24 h after TBI. We show that TBI releases EV containing inflammasome proteins into serum that target the lung to cause ALI, supporting activation of a neural-respiratory-inflammasome axis. Administration of a low-molecular-weight heparin (enoxaparin, a blocker of EV uptake) or treatment with a monoclonal antibody against apoptosis speck-like staining protein containing a caspase recruitment domain (anti-ASC) after adoptive transfer of EV isolated from TBI-injured mice significantly inhibited inflammasome activation in the lungs of recipient mice resulting in improved ALI scores.This axis constitutes an important arm of the innate inflammatory response in lung pathology after TBI and targeting this axis represents a novel therapeutic treatment for TBI-induced ALI.

Subthreshold micropulse laser reduces anti-VEGF injection burden in patients with diabetic macular edema.

PURPOSE: To evaluate the efficacy of micropulse laser in the early treatment of diabetic macular edema (DME) and its associated burden of anti-vascular endothelial growth factor (VEGF) injections. METHODS: This retrospective comparative study compared a group of 19 eyes with DME treated with micropulse laser to a matched control group of 19 eyes with DME treated with ranibizumab injections without micropulse laser. Recorded parameters included previous medical and ocular history, previous and subsequent ranibizumab injections administered for DME, visual acuity (VA), central macular thickness throughout the follow-up period, and the occurrence of any complications. RESULTS: The improvement in VA was comparable in both groups, at 12 months and at the final follow-up. Patients treated with micropulse laser required significantly fewer ranibizumab injections than their controls, both at 12 months (1.7 ± 2.3 vs 5.6 ± 2.1) and by the end of the follow-up (2.6 ± 3.3 vs 9.3 ± 5.1) (p<0.001 for both). No complications related to the micropulse laser were encountered. CONCLUSIONS: Micropulse laser is a safe and effective treatment for DME, which may achieve comparable improvement in VA along with a significant reduction in the burden of anti-VEGF injections. We suggest a treatment approach for its inclusion in the early stages of DME.

Intravitreal dexamethasone in the management of acute endophthalmitis: a comparative retrospective study.

PURPOSE: To compare the clinical outcome of eyes with acute bacterial endophthalmitis treated with intravitreal injection of antibiotics with or without intravitreal dexamethasone. METHODS: This was a retrospective chart review of 63 eyes diagnosed with acute bacterial endophthalmitis and treated with vitreous tap and intravitreal injection of antibiotics, 19 eyes (30.2%) with and 44 eyes (69.8%) without concurrent intravitreal dexamethasone. RESULTS: Visual acuity had significantly improved by 1 week and was maintained long-term (p<0.001). There were no differences in visual outcome or rates of ocular complications between the groups. None of the eyes treated with dexamethasone required repeated intravitreal antibiotic injection while 6 (13.6 %) of the other eyes required repeated intravitreal antibiotic injection (p = 0.09). A subset analysis of 21 eyes that presented with light perception/no light perception vision where vitrectomy was not possible demonstrated that intravitreal antibiotic injection improved vision and achieved similar visual gain as in eyes that presented with hand motion vision or better, with no higher complication rates. CONCLUSIONS:: No adverse effect of intravitreal dexamethasone in the acute management of infectious endophthalmitis was noted. A trend toward less need for repeat intravitreal antibiotic therapy was noted in eyes with acute bacterial endophthalmitis treated with concurrent intravitreal dexamethasone at presentation.

Distinct function of P63 isoforms during embryonic skeletal development.

P63 belongs to the P53 family of transcription factors. There are multiple P63 isoforms that play important functions both in cancer and development. The obvious limb defect in p63 null mice and in human skeletal syndromes with P63 mutations suggest its essential role in long bone development. However, how the different P63 isoforms function during long bone development is largely unknown. We have previously shown that TAP63α, the longest P63 isoform, plays a positive role in embryonic skeletal development, since targeting TAP63α expression in hypertrophic chondrocytes accelerates endochondral ossification at both E17.5 and P1 stages. Here, we report transgenic studies of ΔNP63α, another P63 isoform which lacks the N-terminal transactivation domain compared to TAP63α, using the same hypertrophic chondrocyte-specific Col10a1 control element. No skeletal abnormalities were detected in these Col10a1-ΔNP63α transgenic mice at both E17.5 and P1 stages, suggesting less importance of ΔNP63α during late embryonic skeletal development. To further investigate the function of P63 isoforms during early skeletal development, we have generated ΔNP63α and TAP63α transgenic mice using a chondrocyte-specific Col2a1 control element. Surprisingly, while no skeletal defect was shown in the Col2a1-ΔNP63α transgenic mice, reduced ossification was observed in the digit and tail bones of Col2a1-TAP63α transgenic mice at both E17.5 and P1 stages compared to their wild-type littermates. Expression profiling and immunohistochemical analysis detected upregulated expression of Sox9, a major negative regulator of endochondral ossification, in Col2a1-TAP63α transgenic mice. Taken together, our results suggest a distinct function of P63 isoforms, herein, ΔNP63α and TAP63α, during endochondral ossification.

Transcription factor CCAAT/enhancer-binding protein alpha and critical circadian clock downstream target gene PER2 are highly deregulated in diffuse large B-cell lymphoma.

Disturbances of circadian rhythms and mammalian clock genes have been implicated in the etiologies of many chronic illnesses, including cancer. We show that transcription factor CCAAT/enhancer-binding protein alpha (C/EBPalpha)-regulated PER2 activation is a potential tumor suppressor pathway in diffuse large B-cell lymphoma (DLBCL), one of the commonest types of mature B-cell lymphoma. Expression analysis of human B-cell lymphoma samples including DLBCL (n = 50), mantle cell (n = 21), follicular (n = 25) and Burkitt (n = 18) lymphoma revealed markedly down-regulated CEBPA and PER2 mRNA levels exclusively in DLBCL samples compared to control lymphatic tissue. We demonstrated direct regulation of the circadian core clock gene PER2 by C/EBPalpha in the pro-B cell line Ba/F3, and forced expression of PER2 resulted in decreased proliferation, G0/G1 cell cycle arrest and increased rates of apoptosis. Interestingly, treatment of human DLBCL cell lines with the histone deacetylase-inhibitor suberoylanilide hydroxamic acid (SAHA) significantly increased the expression of C/EBPalpha and Per2, accompanied by cell growth inhibition; in contrast, siRNA knockdown of CEBPA reduced the anti-proliferative effect of SAHA treatment. Our results show for the first time that C/EBPalpha with its associated direct core clock gene target, PER2, are highly deregulated in DLBCL, suggesting an important tumor suppressive pathway in the pathogenesis of this lymphoma entity.

Targeting Runx2 expression in hypertrophic chondrocytes impairs endochondral ossification during early skeletal development.

Runx2 is a known master transcription factor for osteoblast differentiation, as well as an essential regulator for chondrocyte maturation. Recently, more and more data has shown that Runx2 regulates hypertrophic chondrocyte-specific type X collagen gene (Col10a1) expression in different species. However, how Runx2 regulation of Col10a1 expression impacts chondrocyte maturation, an essential step of endochondral bone formation, remains unknown. We have recently generated transgenic mice in which Flag-tagged Runx2 was driven by a cell-specific Col10a1 control element. Significantly increased level of Runx2 and Col10a1 mRNA transcripts were detected in transgenic mouse limbs at both E17.5 (embryonic day 17.5) and P1 (post-natal day1) stages, suggesting an in vivo correlation of Runx2 and Col10a1 expression. Surprisingly, skeletal staining suggested delayed ossification in both the axial and the appendicular skeleton of transgenic mice from E14.5 until P6. Histological analysis showed elongated hypertrophic zones in transgenic mice, with less von Kossa and TUNEL staining in long bone sections at both E17.5 and P1 stages, suggesting defective mineralization due to delayed chondrocyte maturation or apoptosis. Indeed, we detected increased level of anti-apoptotic genes B-cell leukemia/lymphoma 2, Osteopontin, and Sox9 in transgenic mice by real-time RT-PCR. Moreover, immunohistochemistry and Western blotting analysis also suggested increased Sox9 expression in hypertrophic chondrocytes of transgenic mice. Together, our data suggest that targeting Runx2 in hypertrophic chondrocytes upregulates expression of Col10a1 and other marker genes (such as Sox9). This will change the local matrix environment, delay chondrocyte maturation, reduce apoptosis and matrix mineralization, and eventually, lead to impaired endochondral ossification.

Runx2 contributes to murine Col10a1 gene regulation through direct interaction with its cis-enhancer.

We have recently shown that a 150-bp Col10a1 distal promoter (-4296 to -4147 bp) is sufficient to direct hypertrophic chondrocyte-specific reporter (LacZ) expression in vivo. More recently, through detailed sequence analysis we identified two putative tandem-repeat Runx2 binding sites within the 3'-end of this 150-bp region (TGTGGG-TGTGGC, -4187 to -4176 bp). Candidate electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation, and transfection studies demonstrate that these putative Runx2 sites bind Runx2 and mediate upregulated Col10a1/reporter activity in vitro. Transgenic studies using the 5'-sequence without Runx2 sites were not able to drive the cell-specific LacZ reporter activity, suggesting the in vivo requirement of the Runx2 sites located in the 3'-end in mediating Col10a1/reporter expression. Indeed, mutating the Runx2 sites in the context of the 150-bp promoter abolishes its capacity to drive hypertrophic chondrocyte-specific reporter expression in transgenic mice. We have also generated multiple transgenic mouse lines using only the 3'-sequence containing the Runx2 sites to drive the LacZ gene. Interestingly, no hypertrophic chondrocyte-specific blue staining was observed in these transgenic mice. Together, our data support that Runx2 directly interacts with murine Col10a1 cis-enhancer. This interaction is required but not sufficient for cell-specific Col10a1 promoter activity in vivo. Additional cooperative/repressive elements within the 5'- or 3'-sequences of this 150-bp promoter are needed to work with Runx2 together to mediate cell-specific Col10a1 expression. Further delineation of these elements/factors has the potential to identify novel therapeutic targets for multiple skeletal disorders, including osteoarthritis, that show abnormal Col10a1 expression and altered chondrocyte maturation.

Cucurbitacin B induces apoptosis by inhibition of the JAK/STAT pathway and potentiates antiproliferative effects of gemcitabine on pancreatic cancer cells.

Pancreatic cancer is an aggressive malignancy that is generally refractory to chemotherapy, thus posing experimental and clinical challenges. In this study, the antiproliferative effect of the triterpenoid compound cucurbitacin B was tested in vitro and in vivo against human pancreatic cancer cells. Dose-response studies showed that the drug inhibited 50% growth of seven pancreatic cancer cell lines at 10(-7) mol/L, whereas clonogenic growth was significantly inhibited at 5 x 10(-8) mol/L. Cucurbitacin B caused dose- and time-dependent G(2)-M-phase arrest and apoptosis of pancreatic cancer cells. This was associated with inhibition of activated JAK2, STAT3, and STAT5, increased level of p21(WAF1) even in cells with nonfunctional p53, and decrease of expression of cyclin A, cyclin B1, and Bcl-XL with subsequent activation of the caspase cascade. Interestingly, the combination of cucurbitacin B and gemcitabine synergistically potentiated the antiproliferative effects of gemcitabine on pancreatic cancer cells. Moreover, cucurbitacin B decreased the volume of pancreatic tumor xenografts in athymic nude mice by 69.2% (P < 0.01) compared with controls without noticeable drug toxicities. In vivo activation of JAK2/STAT3 was inhibited and expression of Bcl-XL was decreased, whereas caspase-3 and caspase-9 were up-regulated in tumors of drug-treated mice. In conclusion, we showed for the first time that cucurbitacin B has profound in vitro and in vivo antiproliferative effects against human pancreatic cancer cells, and the compound may potentate the antiproliferative effect of the chemotherapeutic agent gemcitabine. Further clinical studies are necessary to confirm our findings in patients with pancreatic cancer.