TPS773 Background: Treatment with Regorafenib (REGO) has shown significant clinical benefits in metastatic colorectal cancer (mCRC) patients (pts) as demonstrated in the CORRECT and CONCUR trials. Results from both studies suggest that subgroups have differential responses. Further research to identify these subgroups through the identification of molecular biomarkers is needed. Methods: Forty pts with refractory mCRC are being enrolled in this study. The primary objective is to prospectively identify tissue and serum-based biomarkers that can predict response to REGO. Secondary objectives are to determine molecular mechanisms by which REGO controls refractory mCRC, as well as molecular pathways involved in the acquisition of resistance. Tumor and blood samples are obtained prior to and 2 weeks after starting REGO. Blood samples are collected on day 1 of each cycle thereafter. Pts will receive 160 mg REGO daily for 3 weeks of each 4-week cycle until disease progression or unacceptable toxicity. Multi-omic based biomarker discovery approaches will be used to uncover predictive marker candidates with special attention to the tumor microenvironment. Laser capture microdissection will be used on tumor tissue to procure highly enriched populations of pt-matched epithelial and stromal/immune cell infiltrates. Each of these entities will be analyzed for RNA expression changes and protein signaling/drug target activation mapping. Protein signaling analysis will be performed by reverse phase protein array of key REGO-related proteins and phosphoproteins (e.g. phosphoVEGFR, Tie2, phosphoRET), as well as broad-scale mapping of mitogenic, survival, autophagy, inflammatory, motility, and signaling networks. Tumor profiling will include next-generation sequencing for 592 genes with 53 selected gene fusions, and IHC and FISH/CISH for selected biomarkers, including PDL1, HER2, MSI, TS, ERCC1, and TOPO1. Blood samples will undergo protein, miRNA, and mutated DNA analysis, as well as exosomal signature study via a proprietary synthetic polyligand multiplexed aptamer-based assay. Exploratory analysis of biomarkers will be used to determine correlations between the presence of, or change in, biomarker levels and clinical response. Clinical trial information: NCT01949194.
PARP inhibitors (PARPi) have shown significant improvement in PFS compared to chemotherapy in patients with BRCA1/2m advanced breast cancer (ABC). However, response durability remains a challenge. PARPi activates the cGAS-STING pathway, leading to increased PD-L1 expression and cytotoxic T-cell recruitment, potentially rendering tumors more susceptible to immunotherapy.
Methods
The TALAVE trial (NCT03964532) enrolled two cohorts: cohort 1 included BRCA1/2m, HER2-negative ABC, and cohort 2 included BRCA1/2 wildtype TNBC. Patients received a 4-week induction of talazoparib (1mg daily D1-D28), followed by combined daily talazoparib and avelumab (800mg D1, D15). Serial biopsies were collected for comprehensive molecular analysis, including RNA profiling using NanoString PanCancer IO360TM Panel, GeoMx® Digital Spatial Profiler (DSP) Whole Transcriptome Atlas (WTA), and protein spatial analysis using NanoString GeoMx® DSP Protein Assays, multiplex tissue Cyclic Immunofluorescence (CyCIF), and AKOYA Biosciences Vectra®.
Results
Cohort 1 exhibited significantly prolonged median PFS compared to cohort 2 (9.3 vs. 2.9 months). Protein and RNA assays of pre- and post- treatment biopsies demonstrated distinct differences between the cohorts. Talazoparib monotherapy led to increased PD-L1 protein expression in tumor cells and macrophages. RNA profiling demonstrated disrupted microhomology-mediated end-joining, antiproliferative effects, upregulation of cGAS-STING pathway genes, and enhanced response to interferon signaling after talazoparib monotherapy in cohort 1, whereas these effects were absent in cohort 2. Protein spatial analysis revealed tumor shrinkage and increased T-cell and macrophage infiltration in BRCA1/2m tumors following combination therapy in cohort 1, while cohort 2 showed no significant changes. Importantly, CD8+/PD1+ T cells increased in cohort 1 but decreased in cohort 2 after combination treatment. Two macrophage lineage markers, CD68 and CD163, identified distinct macrophage populations. CD68+ macrophages showed higher expression of cell state markers (PD-L1, pERK, pTBK1, MCL, BCL-xL) compared to CD163+ macrophages in both cohorts. CD68+ macrophages were present within and outside tumor beds, while CD163+ macrophages were predominantly in the stromal region. Notably, CD68+/CD163-/PDL1+/MCL1+/pERK+ macrophages in baseline biopsies correlated with longer PFS when two cohorts are combined.
Conclusions
In TALAVE, responses to PARPi combined with immunotherapy were limited to patients with BRCA1/2m. RNA and protein analyses demonstrated changes in the TME including cGAS-STING activation and immune cell infiltration in BRCA1/2m tumors, consistent with preclinical models. Deep phenotyping of tumor and immune cells, along with spatial analysis, provided valuable insights into the distinct responses, such as the presence of CD68+ macrophage populations associated with longer PFS, potentially contributing to a more immunostimulatory TME favorable for T cells.
Acknowledgements
This work was supported by the Susan G. Komen Foundation (CCR18547597), NCI Cancer Systems Biology Center of Excellence Grant (U54-CA225088), Terri Brodeur Breast Cancer Foundation, The Friends of Dana-Farber, The Harvard Ludwig Center, NIH DF/HCC SPORE in Breast Cancer (P50 CA168504) and NIH NCI R01/R37 CA269499. Study drugs were provided by Pfizer, as part of an alliance between Pfizer and the healthcare business of Merck KGaA, Darmstadt, Germany (CrossRef Funder ID: 10.13039/100009945).
To investigate the expression of epithelial cell transforming sequence 2 (ECT2) in invasive breast cancer and its prognostic significance.ECT2 immunohistochemical detection was performed in 165 breast cancer specimens and 100 normal control tissues. Univariable and multivariable Cox proportional hazards regression model analysis was used to confirm independent prognostic factors. The PHREG procedure linear hypotheses testing method was used to analyse survival data.Expression of ECT2 in breast cancer was significantly higher than that of the normal control group (p<0.001), and it was related to tumour grade, the status of lymph node metastasis, TNM staging, recurrence status, menopausal status, and the Ki-67 proliferation index (p<0.05), and not related to age, tumour size, tumour type, expression of estrogen receptor, progesterone receptor and human epidermal growth factor 2, and triple-negative disease (p>0.05). Univariable analysis showed that expression of ECT2, the status of lymph node metastasis, triple-negative disease and Ki-67 proliferation index were related to the overall survival of patients with breast cancer (p<0.001, p=0.006, p=0.001, p=0.041, respectively). PHREG procedure linear hypotheses testing results for overall survival revealed that high expression of ECT2, lymph node metastasis, triple-negative disease and high Ki-67 proliferation index predicted lower overall survival rates. Multivariable Cox regression indicated that high expression of ECT2 and triple-negative disease were independent prognostic factors for patients with breast cancer (p<0.001, p=0.004, respectively).Expression of ECT2 may be one of the main causes of the occurrence and development of breast cancer, and high expression of ECT2 as an independent prognostic factor predicts a poor prognosis. ECT2 could also be a potential molecular target for designing therapeutic strategies for breast cancer.
Compared with asymptomatic pulmonary cryptococcosis, secondary cutaneous cryptococcosis may be the first clinical manifestation of disseminated infection but it can be difficult to diagnose clinically. The clinical manifestation of cutaneous cryptococcosis is not pathognomonic, varying from nodules to ulcers and plaques, and frequently mimics other pathologies. This case highlights that an isolated tumour can be an initial manifestation of systemic cryptococcosis in a kidney transplant patient.
Hypoxia is a major cause and promoter of pulmonary hypertension (PH), a representative vascular remodeling disease with poor prognosis and high mortality. However, the mechanism underlying how pulmonary arterial system responds to hypoxic stress during PH remains unclear. Endothelial mitochondria are considered signaling organelles on oxygen tension. Results from previous clinical research and our studies suggested a potential role of posttranslational SUMOylation (small ubiquitin-like modifier modification) in endothelial mitochondria in hypoxia-related vasculopathy.Chronic hypoxia mouse model and Sugen/hypoxia rat model were employed as PH animal models. Mitochondrial morphology and subcellular structure were determined by transmission electron and immunofluorescent microscopies. Mitochondrial metabolism was determined by mitochondrial oxygen consumption rate and extracellular acidification rate. SUMOylation and protein interaction were determined by immunoprecipitation.The involvement of SENP1 (sentrin-specific protease 1)-mediated SUMOylation in mitochondrial remodeling in the pulmonary endothelium was identified in clinical specimens of hypoxia-related PH and was verified in human pulmonary artery endothelial cells under hypoxia. Further analyses in clinical specimens, hypoxic rat and mouse PH models, and human pulmonary artery endothelial cells and human embryonic stem cell-derived endothelial cells revealed that short-term hypoxia-induced SENP1 translocation to endothelial mitochondria to regulate deSUMOylation (the reversible process of SUMOylation) of mitochondrial fission protein FIS1 (mitochondrial fission 1), which facilitated FIS1 assembling with fusion protein MFN2 (mitofusin 2) and mitochondrial gatekeeper VDAC1 (voltage-dependent anion channel 1), and the membrane tethering activity of MFN2 by enhancing its oligomerization. Consequently, FIS1 deSUMOylation maintained the mitochondrial integrity and endoplasmic reticulum-mitochondria calcium communication across mitochondrial-associated membranes, subsequently preserving pulmonary endothelial function and vascular homeostasis. In contrast, prolonged hypoxia disabled the FIS1 deSUMOylation by diminishing the availability of SENP1 in mitochondria via inducing miR (micro RNA)-138 and consequently resulted in mitochondrial dysfunction and metabolic reprogramming in pulmonary endothelium. Functionally, introduction of viral-packaged deSUMOylated FIS1 within pulmonary endothelium in mice improved pulmonary endothelial dysfunction and hypoxic PH development, while knock-in of SUMO (small ubiquitin-like modifier)-conjugated FIS1 in mice exaggerated the diseased cellular and tissue phenotypes.By maintaining endothelial mitochondrial homeostasis, deSUMOylation of FIS1 adaptively preserves pulmonary endothelial function against hypoxic stress and consequently protects against PH. The FIS1 deSUMOylation-SUMOylation transition in pulmonary endothelium is an intrinsic pathogenesis of hypoxic PH.
The strawberry (Fragaria × ananassa Duch.) is an important horticultural crop that is widely grown all over the world. Its sweetness, aroma, nutritional value and bright color make it popular. The woodland strawberry (Fragaria vesca) is a model plant for studying non-climacteric fruits because its respiration rate does not change significantly during fruit ripening. The B-box (BBX) protein family is made up of zinc-finger transcription factors important in plant growth and development. In this study, we identified 22 FveBBX genes from the newly released woodland strawberry genome database by comprehensive bioinformatics analysis. Phylogenetic analysis divided these FveBBX genes into five subfamilies. A promoter cis-acting element analysis detected 29 elements related to plant development, light response, abiotic stress and hormone response in the promoter of FveBBX genes. According to transcriptome data, relatively few BBX genes had tissue-specific expression, with examples including FveBBX12, which was expressed only in pre-fertilization cortex and pitch, and FveBBX19, which was specifically expressed in mature anthers. During fruit ripening, the expressions of eight FveBBX genes decreased by more than two-fold, and three FveBBX gene expressions increased more than two-fold both in “Ruegen” and “Yellow Wonder”. After cold and heat stresses, around half of the FveBBX genes displayed altered expression, especially FveBBX16 which showed an 8.3-fold increase in expression after heat treatment, while FveBBX14 showed at least an 11-fold decrease in expression after cold treatment. According to the result of quantitative real-time PCR (qRT-PCR), FveBBX genes’ expression differed depending on the photoperiod. Notably, FveBBX7 gene expression was the opposite during the first 16 h of the long-day (LD) and short-day (SD) conditions. This study provides helpful information for further research on BBX gene activity of the woodland strawberry in plant growth and development and adaptation to temperature and photoperiod environmental conditions.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)