After injury or cytokine stimulation, fibroblasts transdifferentiate into myofibroblasts, contractile cells that secrete extracellular matrix for wound healing and tissue remodeling. Here, a ...genome-wide screen identified TRPC6, a Ca2+ channel necessary and sufficient for myofibroblast transformation. TRPC6 overexpression fully activated myofibroblast transformation, while fibroblasts lacking Trpc6 were refractory to transforming growth factor β (TGF-β) and angiotensin II-induced transdifferentiation. Trpc6 gene-deleted mice showed impaired dermal and cardiac wound healing after injury. The profibrotic ligands TGF-β and angiotensin II induced TRPC6 expression through p38 mitogen-activated protein kinase (MAPK) serum response factor (SRF) signaling via the TRPC6 promoter. Once induced, TRPC6 activates the Ca2+-responsive protein phosphatase calcineurin, which itself induced myofibroblast transdifferentiation. Moreover, inhibition of calcineurin prevented TRPC6-dependent transdifferentiation and dermal wound healing. These results demonstrate an obligate function for TRPC6 and calcineurin in promoting myofibroblast differentiation, suggesting a comprehensive pathway for myofibroblast formation in conjunction with TGF-β, p38 MAPK, and SRF.
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► TRPC6 induction can fully induce fibroblast-to-myofibroblast transformation ► Loss of TRPC6 blocks myofibroblast transformation to TGF-β and fibrotic cytokines ► Calcineurin-NFAT signaling is necessary and sufficient for myofibroblast formation ► TRPC6-calcineurin-mediated myofibroblast conversion utilizes p38 MAPK and SRF activity
Fibroblasts transdifferentiate into myofibroblasts in response to cytokines; myofibroblasts mediate tissue repair and fibrosis. Davis et al. show that the Ca2+ channel TRPC6 and Ca2+-activated phosphatase calcineurin are necessary and sufficient for myofibroblast differentiation, downstream of a TGF-β signaling pathway that utilizes p38 MAPK and the transcription factor SRF.
Myeloid cells are a feature of most tissues. Here we show that during development, retinal myeloid cells (RMCs) produce Wnt ligands to regulate blood vessel branching. In the mouse retina, where ...angiogenesis occurs postnatally, somatic deletion in RMCs of the Wnt ligand transporter Wntless results in increased angiogenesis in the deeper layers. We also show that mutation of Wnt5a and Wnt11 results in increased angiogenesis and that these ligands elicit RMC responses via a non-canonical Wnt pathway. Using cultured myeloid-like cells and RMC somatic deletion of Flt1, we show that an effector of Wnt-dependent suppression of angiogenesis by RMCs is Flt1, a naturally occurring inhibitor of vascular endothelial growth factor (VEGF). These findings indicate that resident myeloid cells can use a non-canonical, Wnt-Flt1 pathway to suppress angiogenic branching.
Stromal interaction molecule 1 (STIM1) is a Ca2+ sensor that partners with Orai1 to elicit Ca2+ entry in response to endoplasmic reticulum (ER) Ca2+ store depletion. While store-operated Ca2+ entry ...(SOCE) is important for maintaining ER Ca2+ homeostasis in non-excitable cells, it is unclear what role it plays in the heart, although STIM1 is expressed in the heart and upregulated during disease. Here we analyzed transgenic mice with STIM1 overexpression in the heart to model the known increase of this protein in response to disease. As expected, STIM1 transgenic myocytes showed enhanced Ca2+ entry following store depletion and partial co-localization with the type 2 ryanodine receptor (RyR2) within the sarcoplasmic reticulum (SR), as well as enrichment around the sarcolemma. STIM1 transgenic mice exhibited sudden cardiac death as early as 6weeks of age, while mice surviving past 12weeks of age developed heart failure with hypertrophy, induction of the fetal gene program, histopathology and mitochondrial structural alterations, loss of ventricular functional performance and pulmonary edema. Younger, pre-symptomatic STIM1 transgenic mice exhibited enhanced pathology following pressure overload stimulation or neurohumoral agonist infusion, compared to controls. Mechanistically, cardiac myocytes isolated from STIM1 transgenic mice displayed spontaneous Ca2+ transients that were prevented by the SOCE blocker SKF-96365, increased L-type Ca2+ channel (LTCC) current, and enhanced Ca2+ spark frequency. Moreover, adult cardiac myocytes from STIM1 transgenic mice showed both increased diastolic Ca2+ and maximal transient amplitude but no increase in total SR Ca2+ load. Associated with this enhanced Ca2+ profile was an increase in cardiac nuclear factor of activated T-cells (NFAT) and Ca2+/calmodulin-dependent kinase II (CaMKII) activity. We conclude that STIM1 has an unexpected function in the heart where it alters communication between the sarcolemma and SR resulting in greater Ca2+ flux and a leaky SR compartment.
•STIM1 transgenic mice showed increased Ca2+ entry following store depletion.•STIM1 transgenic mice develop cardiac hypertrophy and sudden death.•Mitochondrial structure is compromised in STIM1 transgenic mouse hearts.•STIM1 transgenic mice are predisposed to increased disease following insult.•Myocytes isolated from STIM1 transgenic mice have elevated spark frequency.
A critical event in ischemia-based cell death is the opening of the mitochondrial permeability transition pore (MPTP). However, the molecular identity of the components of the MPTP remains unknown. ...Here, we determined that the Bcl-2 family members Bax and Bak, which are central regulators of apoptotic cell death, are also required for mitochondrial pore-dependent necrotic cell death by facilitating outer membrane permeability of the MPTP. Loss of Bax/Bak reduced outer mitochondrial membrane permeability and conductance without altering inner membrane MPTP function, resulting in resistance to mitochondrial calcium overload and necrotic cell death. Reconstitution with mutants of Bax that cannot oligomerize and form apoptotic pores, but still enhance outer membrane permeability, permitted MPTP-dependent mitochondrial swelling and restored necrotic cell death. Our data predict that the MPTP is an inner membrane regulated process, although in the absence of Bax/Bak the outer membrane resists swelling and prevents organelle rupture to prevent cell death. DOI:http://dx.doi.org/10.7554/eLife.00772.001.
The purpose of this study was to compare the outcomes of patients with non-small cell lung cancer (NSCLC) brain metastases treated with stereotactic radiotherapy (SRT) alone versus SRT and immune ...checkpoint inhibitors (ICIs).
Patients treated for their first diagnosis of intracranial metastases with SRT or SRT plus ICI were retrospectively identified. Overall survival (OS), local control (LC), distant brain failure (DBF), neurologic death, and rates of radiation necrosis were calculated. Univariate (UVA) and multivariable (MVA) analyses with competing risk analysis were performed.
Seventy-seven patients with 132 lesions were analyzed, including 44 patients with 68 lesions in the SRT group and 33 patients with 64 lesions in the SRT plus ICI group. There were no differences in baseline factors between groups. Use of ICI predicted for decreased DBF (hazard ratio HR, 0.45; 95% confidence interval CI, 0.24-0.84; P = .01), decreased rates of neurologic death (HR, 0.29; 95% CI, 0.10-0.85; P = .02), and better OS (HR, 0.46; 95% CI, 0.23-0.91; P = .03). Two-year LC was 97% for the SRT + ICI group, and 86% for the SRT-alone group (P = .046). Actuarial 2-year DBF was 39% for the SRT + ICI group and 66% for the SRT alone group (P = .016). On MVA, ICI use persisted in predicting lower incidence of neurologic death (HR, 0.25; 95% CI, 0.09-0.72; P = .01) and DBF (HR, 0.47; 95% CI, 0.25-0.85; P = .01) when adjusted for competing risk of death.
In this cohort of patients with NSCLC brain metastases, ICI use combined with SRT predicted for improved LC and OS and decreased DBF and risk of neurologic death.
Immune checkpoint inhibitors (ICIs) are routinely used in patients with metastatic non–small-cell lung cancer (NSCLC). Stereotactic radiation (SRT) alone is currently the standard treatment for most NSCLC brain metastases. It is unknown if receiving ICIs at the time of SRT improves neurologic outcomes. Herein, we have shown that combining SRT with ICIs improves overall survival, reduces distant brain failure, and reduces neurologic death in patients with NSCLC brain metastases.
Management of cutaneous malignancies can be particularly challenging when they are located in the periocular region. The standard of care for localized disease is complete surgical excision, but this ...may not be possible without significant disruption to visual structures and facial appearance. Definitive radiation may be an option for some patients who cannot or do not wish to undergo surgery. Advances in systemic treatment options for locally advanced and metastatic skin cancers in the past 10 years have prompted investigation into neoadjuvant treatment of periocular cancers. The use of chemotherapy, immune checkpoint inhibitors, and targeted therapies have all been reported with varying degrees of success. For many patients, targeted therapies or immune checkpoint inhibitors should be considered depending on the cancer type, symptoms, and goals with the input of a multidisciplinary cancer care team. In this article, we systematically review the latest updates in surgical, radiotherapeutic, and medical management of periocular malignancies.
The applicability of modern prospective data on adjuvant radiotherapy (RT) fields in patients with micrometastases is limited because many trials occurred prior to routine measurement of nodal ...metastasis size and modern sentinel lymph node evaluation techniques. We aimed to determine prognostic factors for patients with micrometastases and evaluate the impact of adjuvant RT on disease outcomes.
Patients diagnosed with pathologic T1-T3 N1mi breast cancers between 2004-2015 were identified. Cox proportional hazards methods were used to determine characteristics predictive of locoregional recurrence (LRR). Tumor and treatment-specific factors were further evaluated using log-rank statistics to compare rates of LRR-free survival.
This analysis included 156 patients. On multivariable analysis, grade 3 histology (HR 10.84, 95% CI 2.72-43.21) and adjuvant RT (HR 0.22, 95% CI 0.06-0.81) were independent predictors of LRR. Among patients with grade 1-2 histology, 5-year LRR-free survival was 98.8% in patients who received adjuvant RT versus 100% in patients who did not receive adjuvant RT (P = .82). Among patients with grade 3 histology, 5-year LRR-free survival was 90.1% in patients who received adjuvant RT versus 53.0% in patients who did not receive adjuvant RT (P = .025), and 100% in patients receiving comprehensive nodal irradiation versus 76.7% in patients receiving whole breast irradiation or no RT (P = .045).
Patients with grade 3 micrometastases are at substantial risk for LRR. Adjuvant RT, including comprehensive nodal irradiation, should be strongly considered in these women.
Optimal adjuvant radiotherapy fields in patients with micrometastases are controversial. In this retrospective study, 156 patients with micrometastases were analyzed. Women with grade 3 histology were observed to be at substantial risk for LRR. Adjuvant RT was associated with a lower risk of LRR. Adjuvant RT, including comprehensive nodal irradiation, should be strongly considered for women with grade 3 micrometastases.
•Excellent locoregional control of HPV + OPSCC is achieved with direct GTV to PTV expansions.•The majority of treatment failures were located within the high-dose planning volume.•Low toxicity ...profile was achieved with one-year gastrostomy tube retention rate of 6%.
To evaluate clinical outcomes and patterns of failure using a direct gross tumor volume to planning target volume expansion in patients with p16-positive oropharyngeal squamous cell carcinoma.
We performed a retrospective review of patients with p16-positive oropharyngeal squamous cell carcinomas treated between 2002 and 2017 with primary radiotherapy with or without concurrent systemic therapy. Patient and disease characteristics associated with disease control and clinical outcomes were analyzed by Cox proportional hazards regression and Kaplan-Meier analyses. Imaging at the time of first failure was used to categorize failure patterns.
We identified 134 patients with a median follow-up of 56.2 months (range 8.2–160.2 months). Local and regional control at 5 years was 91.5% (95% CI: 86.8–96.4%), and 90.8% (95% CI: 85.6–96.2%), respectively. Of the 14 locoregional failures, there were 10 in-field (Type A), 3 marginal (Type B), and 1 geographic (Type E). Age >70 years (HR 5.42; 95% CI: 1.87–15.68) and T4 versus T1-3 (HR 4.09; 95% CI: 1.01–2.65) were associated with increased rates of locoregional failure on multivariate analysis. The rate of gastrostomy tube retention at one year was 6.0% (range 2.8–12.7%).
Management of patients with p16-positive oropharyngeal squamous cell carcinoma using definitive radiotherapy and a high-dose planning target volume created without a gross tumor volume to clinical tumor volume expansion resulted in high locoregional control with the vast majority of failures occurring within the high-dose field. These data warrant prospective evaluation of this technique as a therapy de-intensification approach.
Approximately 30% of patients with diffuse large B cell lymphoma (DLBCL) will develop relapsed or treatment-refractory disease after primary chemotherapy. Patients unable to undergo aggressive ...chemotherapy and stem cell transplant or chimeric antigen receptor T-cell (CAR T-cell) therapy have limited treatment options. Here, we investigated the safety and efficacy of combining obinutuzumab with cytoreductive radiation to all areas of disease in patients with relapsed DLBCL.
A retrospective review of patients with treatment refractory DLBCL was performed. All patients were treated with external beam radiation to all sites of refractory disease with concurrent and adjuvant obinutuzumab. Toxicities were evaluated based on Common Terminology Criteria for Adverse Events v5.0 criteria. Kaplan-Meier analysis was used to calculate progression-free survival and overall survival.
Between 2016 and 2022, 7 patients with refractory DLBCL were treated with concurrent radiation and obinutuzumab. No grade 3 or greater treatment-related toxicity was observed. Four of the 7 patients had a complete response at the radiated site on first postradiation imaging. The median progression-free survival and overall survival were 30 months.
In this small cohort of treatment-refractory patients with DLBCL, the combination of radiation and obinutuzumab was well tolerated without excessive treatment-related toxicity. The combination resulted in durable disease control with a prolonged overall survival without additional treatment in a subset of patients.
Background
To define the location of the initial contralateral lymph node (LN) metastasis in patients with oropharynx cancer.
Methods
The location of the LN centroids from patients with oropharynx ...cancer and a single radiographically positive contralateral LN was defined. A clinical target volume (CTV) inclusive of all LN centroids was created, and its impact on dose to organs at risk was assessed.
Results
We identified 55 patients of which 49/55 had a single contralateral LN in level IIA, 4/55 in level III, 1/55 in level IIB, and 1/55 in the retropharynx. Mean radiation dose to the contralateral parotid gland was 15.1 and 21.0 Gy, (p <0.001) using the modeled high‐risk elective CTV and a consensus CTV, respectively.
Conclusions
We present a systematic approach for identifying the contralateral nodal regions at highest risk of harboring subclinical disease in patients with oropharynx cancer that warrants prospective clinical study.
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