Systemic administration of immune checkpoint blockade (ICB) monoclonal antibodies (mAbs) can unleash antitumor functions of T cells but is associated with variable response rates and off-target toxicities. We hypothesized that antitumor efficacy of ICB is limited by the minimal accumulation of mAb within tissues where antitumor immunity is elicited and regulated, which include the tumor microenvironment (TME) and secondary lymphoid tissues. In contrast to systemic administration, intratumoral and intradermal routes of administration resulted in higher mAb accumulation within both the TME and its draining lymph nodes (LNs) or LNs alone, respectively. The use of either locoregional administration route resulted in pronounced T cell responses from the ICB therapy, which developed in the secondary lymphoid tissues and TME of treated mice. Targeted delivery of mAb to tumor-draining lymph nodes (TdLNs) alone was associated with enhanced antitumor immunity and improved therapeutic effects compared to conventional systemic ICB therapy, and these effects were sustained at reduced mAb doses and comparable to those achieved by intratumoral administration. These data suggest that locoregional routes of administration of ICB mAb can augment ICB therapy by improving immunomodulation within TdLNs.

Whole-slide histology images contain information that is valuable for clinical and basic science investigations of cancer but extracting quantitative measurements from these images is challenging for researchers who are not image analysis specialists. In this article, we describe HistomicsML2, a software tool for learn-by-example training of machine learning classifiers for histologic patterns in whole-slide images. This tool improves training efficiency and classifier performance by guiding users to the most informative training examples for labeling and can be used to develop classifiers for prospective application or as a rapid annotation tool that is adaptable to different cancer types. HistomicsML2 runs as a containerized server application that provides web-based user interfaces for classifier training, validation, exporting inference results, and collaborative review, and that can be deployed on GPU servers or cloud platforms. We demonstrate the utility of this tool by using it to classify tumor-infiltrating lymphocytes in breast carcinoma and cutaneous melanoma. Significance: An interactive machine learning tool for analyzing digital pathology images enables cancer researchers to apply this tool to measure histologic patterns for clinical and basic science studies.

The etiology of ulcerative colitis is poorly understood and is likely to involve perturbation of the complex interactions between the mucosal immune system and the commensal bacteria of the gut, with cytokines acting as important cross-regulators. Here we use IFN receptor-deficient mice in a dextran sulfate sodium (DSS) model of acute intestinal injury to study the contributions of type I and III interferons (IFN) to the initiation, progression and resolution of acute colitis. We find that mice lacking both types of IFN receptors exhibit enhanced barrier destruction, extensive loss of goblet cells and diminished proliferation of epithelial cells in the colon following DSS-induced damage. Impaired mucosal healing in double IFN receptor-deficient mice is driven by decreased amphiregulin expression, which IFN signaling can up-regulate in either the epithelial or hematopoietic compartment. Together, these data underscore the pleiotropic functions of IFNs and demonstrate that these critical antiviral cytokines also support epithelial regeneration following acute colonic injury.

Myotonic dystrophy types 1 and 2 are a group of complex genetic disorders resulting from the expansion of (CTG)n nucleotide repeats in the DMPK gene. In addition to the hallmark manifestations of myotonia and skeletal muscle atrophy, myotonic dystrophy also affects a myriad of other organs including the heart, lungs, as well as the skin. The most common cutaneous manifestations of myotonic dystrophy are early male frontal alopecia and adult-onset pilomatricomas. Myotonic dystrophy also increases the risk of developing malignant skin diseases such as basal cell carcinoma and melanoma. To aid in the diagnosis and treatment of myotonic dystrophy related skin conditions, it is important for the dermatologist to become cognizant of the common and rare cutaneous manifestations of this genetic disorder. We performed a PubMed search using the key terms “myotonic dystrophy” AND “cutaneous” OR “skin” OR “dermatologic” AND “manifestation” OR “finding.” The resulting publications were manually reviewed for additional relevant publications, and subsequent additional searches were performed as needed, especially regarding the molecular mechanisms of pathogenesis. In this review, we aim to provide an overview of myotonic dystrophy types 1 and 2 and summarize their cutaneous manifestations as well as potential mechanisms of pathogenesis.

Advances in molecular pathology have changed the landscape of oncology. The ability to interrogate tissue samples for oncogene amplification, driver mutations, and other molecular alterations provides clinicians with an enormous level of detail about their patient's cancer. In some cases, this information informs treatment decisions, especially those related to targeted anti-cancer therapies. However, in terms of immune-based therapies, it is less clear how to use such information. Likewise, despite studies demonstrating the pivotal role of neoantigens in predicting responsiveness to immune checkpoint blockade, it is not known if the expression of neoantigens impacts the response to targeted therapies despite a growing recognition of their diverse effects on immunity. To realize the promise of 'personalized medicine', it will be important to develop a more integrated understanding of the relationships between oncogenic events and processes governing anti-tumor immunity. One area of investigation to explore such relationships centers on defining how ErbB/HER activation and signal transduction influences antigen processing and presentation.

Lifestyle factors, including diet, play an important role in the survival of cancer patients. However, the molecular mechanisms underlying pathogenic links between diet and particular oncogenic mutations in human cancers remain unclear. We recently reported that the ketone body acetoacetate selectively enhances BRAF V600E mutant-dependent MEK1 activation in human cancers. Here we show that a high-fat ketogenic diet increased serum levels of acetoacetate, leading to enhanced tumor growth potential of BRAF V600E-expressing human melanoma cells in xenograft mice. Treatment with hypolipidemic agents to lower circulating acetoacetate levels or an inhibitory homolog of acetoacetate, dehydroacetic acid, to antagonize acetoacetate-BRAF V600E binding attenuated BRAF V600E tumor growth. These findings reveal a signaling basis underlying a pathogenic role of dietary fat in BRAF V600E-expressing melanoma, providing insights into the design of conceptualized “precision diets” that may prevent or delay tumor progression based on an individual's specific oncogenic mutation profile.

Graft-versus-host disease (GvHD) is a major cause of morbidity and mortality in patients treated with allogeneic hematopoietic stem cell transplantation (HSCT). Post-transplant immunosuppressive drugs incompletely control GvHD and increase susceptibility to opportunistic infections. In this study we used flagellin, a TLR5 agonist protein (~50 kDa) extracted from bacterial flagella, as a novel experimental treatment strategy to reduce both acute and chronic GvHD in allogeneic HSCT recipient. Based upon the radio-protective effects of flagellin, we hypothesized that flagellin could ameliorate GvHD in lethally irradiated murine models of allogeneic HSCT. Two doses of highly purified flagellin (administered 3 hrs. before irradiation and 24 hrs. after HSCT) reduced GvHD and led to better survival in both H-2b → CB6F1 and H-2k → B6 allogeneic HSCT models while preserving over 99% donor T cells chimerism. Flagellin treatment preserved long-term post-transplant immune reconstitution characterized by more donor thymic-derived CD4+CD25+foxp3+ regulatory T cells (Tregs) and significantly enhanced anti-viral immunity following murine cytomegalovirus (mCMV) infection model. The proliferation index and activation status of donor spleen-derived T cells, and serum concentration of pro-inflammatory cytokines in flagellin-treated recipients were reduced significantly within 4 days post-transplant compared with the PBS-treated control recipients. Allogeneic transplantation of radiation chimeras previously engrafted with TLR5 knockout hematopoietic cells showed that interactions between flagellin and TLR5 expressed on both donor hematopoietic and host non-hematopoietic cells were required to reduce GvHD. Thus, the peri-transplant administration of flagellin is a novel therapeutic approach control GvHD while preserving post-transplant donor immunity.

Objective To examine the prognostic value of tumor major histocompatibility complex I (MHCI) expression on survival and recurrence in patients with clear cell renal cell carcinoma (RCC). Methods Fifty-three patients that underwent nephrectomy at our institution for clear cell RCC (T1-T3) with ≥4 years of follow-up were queried from our nephrectomy database. Immunohistochemical staining for MHCI was performed on tumor specimens and MHCI expression was quantified with an automated image analysis technique. Patients were divided into high and low MHCI expression groups in order to study the relationship between MHCI expression and prognosis using the Kaplan-Meier method and log-rank test. Results Overall survival and recurrence free survival were increased in the high MHCI expression group compared to the low MHCI expression group (log-rank, p = 0.036 and p = 0.028, respectively). Patients alive at the end of the study had higher MHCI expression (mean positivity score 0.82) than those that died of disease (mean positivity score 0.76, t test, p = 0.030). Patients that did not develop recurrence during the study period had higher MHCI expression (mean positivity score 0.83) than those that did develop recurrence (mean positivity score 0.78), but this difference was not significant (t test, p = 0.079). Conclusion Our data demonstrate that high MHCI expression confers improved overall and recurrence free survival in patients with clear cell RCC and could serve as an important prognostic tool in identifying high-risk patients.

Background: Population-based data on melanoma survival are important for understanding the impact of demographic and clinical factors on prognosis. Objective: We describe melanoma survival by age, sex, race/ethnicity, stage, depth, histology, and site. Methods: Using Surveillance, Epidemiology, and End Results data, we calculated unadjusted cause-specific survival up to 10 years from diagnosis for 68,495 first primary cases of melanoma diagnosed from 1992 to 2005. Cox multivariate analysis was performed for 5-year survival. Data from 1992 to 2001 were divided into 3 time periods to compare stage distribution and differences in stage-specific 5-year survival over time. Results: Melanomas that had metastasized (distant stage) or were thicker than 4.00 mm had a poor prognosis (5-year survival: 15.7% and 56.6%). The 5-year survival for men was 86.8% and for persons given the diagnosis at age 65 years or older was 83.2%, varying by stage at diagnosis. Scalp/neck melanoma had lower 5-year survival (82.6%) than other anatomic sites; unspecified/overlapping lesions had the least favorable prognosis (41.5%). Nodular and acral lentiginous melanomas had the poorest 5-year survival among histologic subtypes (69.4% and 81.2%, respectively). Survival differences by race/ethnicity were observed in the unadjusted survival, but nonsignificant in the multivariate analysis. Overall 5-year melanoma survival increased from 87.7% to 90.1% for melanomas diagnosed in 1992 through 1995 compared with 1999 through 2001, and this change was not clearly associated with a shift toward localized diagnosis. Limitations: Prognostic factors included in revised melanoma staging guidelines were not available for all study years and were not examined. Conclusions: Poorer survival from melanoma was observed among those given the diagnosis at late stage and older age. Improvements in survival over time have been minimal. Although newly available therapies may impact survival, prevention and early detection are relevant to melanoma-specific survival.

Objective: Regenerative medicine seeks to stall or to reverse the pathologic consequences of chronic diseases. Many people with diabetes have peripheral arterial disease (PAD), which increases their already high risk of major amputation. Cellular therapies are a promising regenerative medicine approach to PAD that can be used to focally inject regenerative cells to endangered tissue beds. Mesenchymal stem cells (MSCs) are known to promote tissue regeneration through stromal support and paracrine stimulation of new blood vessels (angiogenesis). Whereas little is known about human diabetic MSCs (dMSCs), particularly those from patients with PAD, dMSCs have a limited expansion capacity but can be improved with human platelet lysate (PL) supplementation. PL is rich in many growth factors, including epidermal growth factor (EGF), which is known to be important to cell proliferation and survival signaling pathways. We hypothesize that dMSCs have a reversible defect in EGF receptor pathways. The objective of this work was to test this hypothesis using dMSCs from PAD patients. Methods: The secretome expression of EGF and prominent angiogens was characterized from bone marrow (BM)-derived and adipose tissue-derived (ATD) dMSCs from five patients (six limbs) undergoing major amputation. Western blot was used to characterize the AKT and extracellular signal-regulated protein kinases 1 and 2 expression in dMSCs under standard culture (5% fetal bovine serum plus fibroblast growth factor 2 [FGF2]), 5% human PL, or 5% fetal bovine serum plus EGF. Healthy donor MSCs were control cells. The angiogenic activity of BM- and ATD-dMSCs was tested on human umbilical vein endothelial cells (ECs). Paired t-test, analysis of variance, and Kruskal-Wallis tests were used as appropriate. Results: Both BM- and ATD-dMSCs had typical MSC surface marker expression and similar expansion profiles, and they did not express EGF in their secretome. PL supplementation of dMSCs improved AKT signaling, but they were resistant to FGF2 activation of extracellular signal-regulated protein kinases 1 and 2. EGF supplementation led to similar AKT expression as with PL, but PL had greater phosphorylation of AKT at 30 and 60 minutes. The conditioned media from both BM- and ATD-dMSCs had robust levels of prominent angiogens (vascular endothelial growth factor, monocyte chemoattractant protein 1, hepatocyte growth factor), which stimulated EC proliferation and migration, and the co-culture of dMSCs with ECs led to significantly longer EC sprouts in three-dimensional gel than EC-alone pellets. Conclusions: PL and EGF supplementation improves AKT expression in dMSCs over that of FGF2, but PL improved pAKT over that of EGF. Thus, PL supplementation strategies may improve AKT signaling, which could be important to MSC survival in cellular therapies. Furthermore, BM- and ATD-dMSCs have similar secretomes and robust in vitro angiogenic activity, which supports pursuing dMSCs from both reservoirs in regenerative medicine strategies. Clinical Relevance: Cellular therapies with mesenchymal stem cells (MSCs) hold great promise in the treatment of chronic diseases like peripheral arterial disease (PAD). Diabetic patients have a premature onset and rapid progression of PAD, but the suitability of MSCs in diabetic patients is not clear. We have found that both bone marrow and adipose tissue-derived MSCs had robust angiogenic effects in vitro. The signaling defects identified in the epidermal growth factor signaling axis were partially recovered with platelet lysate supplementation. By correcting the defects identified, we may be able to improve the cell survival and expansion of MSCs for use in diabetic patients with PAD.