bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Cross-talk between SOX2 and TGFβ Signaling Regulates EGFR–TKI Tolerance and Lung Cancer Dissemination
Authors: Kuo Ming-Han , Lee An-Chun , Hsiao Shih-Hsin , Lin Sey-En , Chiu Yu-Fan , Yang Li-Hao , Yu Chia-Cherng , Chiou Shih-Hwa , Huang Hsien-Neng , Ko Jen-Chung , Chou Yu-Ting
Published: March 2024

Abstract
Regulation of the stemness factor, SOX2, by cytokine stimuli controls self-renewal and differentiation in cells. Activating mutations in EGFR are proven therapeutic targets for tyrosine kinase inhibitors (TKI) in lung adenocarcinoma, but acquired resistance to TKIs inevitably occurs. The mechanism by which stemness and differentiation signaling emerge in lung cancers to affect TKI tolerance and lung cancer dissemination has yet to be elucidated. Here, we report that cross-talk between SOX2 and TGFβ signaling affects lung cancer cell plasticity and TKI tolerance. TKI treatment favored selection of lung cancer cells displaying mesenchymal morphology with deficient SOX2 expression, whereas SOX2 expression promoted TKI sensitivity and inhibited the mesenchymal phenotype. Preselection of EGFR-mutant lung cancer cells with the mesenchymal phenotype diminished SOX2 expression and TKI sensitivity, whereas SOX2 silencing induced vimentin, but suppressed BCL2L11, expression and promoted TKI tolerance. TGFβ stimulation downregulated SOX2 and induced epithelial-to-mesenchymal transdifferentiation accompanied by increased TKI tolerance, which can interfere with ectopic SOX2 expression. SOX2-positive lung cancer cells exhibited a lower dissemination capacity than their SOX2-negative counterparts. Tumors expressing low SOX2 and high vimentin signature were associated with worse survival outcomes in patients with EGFR mutations. These findings provide insights into how cancer cell plasticity regulated by SOX2 and TGFβ signaling affects EGFR-TKI tolerance and lung cancer dissemination.
Significance:
These findings suggest the potential of SOX2 as a prognostic marker in EGFR-mutant lung cancer, as SOX2-mediated cell plasticity regulated by TGFβ stimulation and epigenetic control affects EGFR-TKI tolerance and cancer dissemination.
Data from Telomere Maintenance Mechanisms Define Clinical Outcome in High-Risk Neuroblastoma
Authors: Koneru Balakrishna , Lopez Gonzalo , Farooqi Ahsan , Conkrite Karina L. , Nguyen Thinh H. , Macha Shawn J. , Modi Apexa , Rokita Jo Lynne , Urias Eduardo , Hindle Ashly , Davidson Heather , Mccoy Kristyn , Nance Jonas , Yazdani Vanda , Irwin Meredith S. , Yang Shengping , Wheeler David A. , Maris John M. , Diskin Sharon J. , Reynolds C. Patrick
Published: March 2024

Abstract
Neuroblastoma is a childhood cancer with heterogeneous clinical outcomes. To comprehensively assess the impact of telomere maintenance mechanism (TMM) on clinical outcomes in high-risk neuroblastoma, we integrated the C-circle assay [a marker for alternative lengthening of telomeres (ALT)], TERT mRNA expression by RNA-sequencing, whole-genome/exome sequencing, and clinical covariates in 134 neuroblastoma patient samples at diagnosis. In addition, we assessed TMM in neuroblastoma cell lines (n = 104) and patient-derived xenografts (n = 28). ALT was identified in 23.4% of high-risk neuroblastoma tumors and genomic alterations in ATRX were detected in 60% of ALT tumors; 40% of ALT tumors lacked genomic alterations in known ALT-associated genes. Patients with high-risk neuroblastoma were classified into three subgroups (TERT-high, ALT+, and TERT-low/non-ALT) based on presence of C-circles and TERT mRNA expression (above or below median TERT expression). Event-free survival was similar among TERT-high, ALT+, or TERT-low/non-ALT patients. However, overall survival (OS) for TERT-low/non-ALT patients was significantly higher relative to TERT-high or ALT patients (log-rank test; P < 0.01) independent of current clinical and molecular prognostic markers. Consistent with the observed higher OS in patients with TERT-low/non-ALT tumors, continuous shortening of telomeres and decreasing viability occurred in low TERT–expressing, non-ALT patient-derived high-risk neuroblastoma cell lines. These findings demonstrate that assaying TMM with TERT mRNA expression and C-circles provides precise stratification of high-risk neuroblastoma into three subgroups with substantially different OS: a previously undescribed TERT-low/non-ALT cohort with superior OS (even after relapse) and two cohorts of patients with poor survival that have distinct molecular therapeutic targets.
Significance:
These findings assess telomere maintenance mechanisms with TERT mRNA and the ALT DNA biomarker C-circles to stratify neuroblastoma into three groups, with distinct overall survival independent of currently used clinical risk classifiers.
Data from iNOS Regulates the Therapeutic Response of Pancreatic Cancer Cells to Radiotherapy
Authors: Pereira Patricia M.R. , Edwards Kimberly J. , Mandleywala Komal , Carter Lukas M. , Escorcia Freddy E. , Campesato Luis Felipe , Cornejo Mike , Abma Lolkje , Mohsen Abu-Akeel , Iacobuzio-Donahue Christine A. , Merghoub Taha , Lewis Jason S.
Published: March 2024

Abstract
Pancreatic ductal adenocarcinoma (PDAC) is highly resistant to radiotherapy, chemotherapy, or a combination of these modalities, and surgery remains the only curative intervention for localized disease. Although cancer-associated fibroblasts (CAF) are abundant in PDAC tumors, the effects of radiotherapy on CAFs and the response of PDAC cells to radiotherapy are unknown. Using patient samples and orthotopic PDAC biological models, we showed that radiotherapy increased inducible nitric oxide synthase (iNOS) in the tumor tissues. Mechanistic in vitro studies showed that, although undetectable in radiotherapy-activated tumor cells, iNOS expression and nitric oxide (NO) secretion were significantly increased in CAFs secretome following radiotherapy. Culture of PDAC cells with conditioned media from radiotherapy-activated CAFs increased iNOS/NO signaling in tumor cells through NF-κB, which, in turn, elevated the release of inflammatory cytokines by the tumor cells. Increased NO after radiotherapy in PDAC contributed to an acidic microenvironment that was detectable using the radiolabeled pH (low) insertion peptide (pHLIP). In murine orthotopic PDAC models, pancreatic tumor growth was delayed when iNOS inhibition was combined with radiotherapy. These data show the important role that iNOS/NO signaling plays in the effectiveness of radiotherapy to treat PDAC tumors.
Significance:
A radiolabeled pH-targeted peptide can be used as a PET imaging tool to assess therapy response within PDAC and blocking iNOS/NO signaling may improve radiotherapy outcomes.
Data from Cooperative Blockade of PKCα and JAK2 Drives Apoptosis in Glioblastoma
Authors: Wong Robyn A. , Luo Xujun , Lu Mimi , An Zhenyi , Haas-Kogan Daphne A. , Phillips Joanna J. , Shokat Kevan M. , Weiss William A. , Fan Qi Wen
Published: March 2024

Abstract
The mTOR signaling is dysregulated prominently in human cancers including glioblastoma, suggesting mTOR as a robust target for therapy. Inhibitors of mTOR have had limited success clinically, however, in part because their mechanism of action is cytostatic rather than cytotoxic. Here, we tested three distinct mTOR kinase inhibitors (TORKi) PP242, KU-0063794, and sapanisertib against glioblastoma cells. All agents similarly decreased proliferation of glioblastoma cells, whereas PP242 uniquely induced apoptosis. Apoptosis induced by PP242 resulted from off-target cooperative inhibition of JAK2 and protein kinase C alpha (PKCα). Induction of apoptosis was also decreased by additional on-target inhibition of mTOR, due to induction of autophagy. As EGFR inhibitors can block PKCα, EGFR inhibitors erlotinib and osimertinib were tested separately in combination with the JAK2 inhibitor AZD1480. Combination therapy induced apoptosis of glioblastoma tumors in both flank and in patient-derived orthotopic xenograft models, providing a preclinical rationale to test analogous combinations in patients.
Significance:
These findings identify PKCα and JAK2 as targets that drive apoptosis in glioblastoma, potentially representing a clinically translatable approach for glioblastoma.
Data from Localized Metabolomic Gradients in Patient-Derived Xenograft Models of Glioblastoma
Authors: Randall Elizabeth C. , Lopez Begoña G.C. , Peng Sen , Regan Michael S. , Abdelmoula Walid M. , Basu Sankha S. , Santagata Sandro , Yoon Haejin , Haigis Marcia C. , Agar Jeffrey N. , Tran Nhan L. , Elmquist William F. , White Forest M. , Sarkaria Jann N. , Agar Nathalie Y.R.
Published: March 2024

Abstract
Glioblastoma (GBM) is increasingly recognized as a disease involving dysfunctional cellular metabolism. GBMs are known to be complex heterogeneous systems containing multiple distinct cell populations and are supported by an aberrant network of blood vessels. A better understanding of GBM metabolism, its variation with respect to the tumor microenvironment, and resulting regional changes in chemical composition is required. This may shed light on the observed heterogeneous drug distribution, which cannot be fully described by limited or uneven disruption of the blood–brain barrier. In this work, we used mass spectrometry imaging (MSI) to map metabolites and lipids in patient-derived xenograft models of GBM. A data analysis workflow revealed that distinctive spectral signatures were detected from different regions of the intracranial tumor model. A series of long-chain acylcarnitines were identified and detected with increased intensity at the tumor edge. A 3D MSI dataset demonstrated that these molecules were observed throughout the entire tumor/normal interface and were not confined to a single plane. mRNA sequencing demonstrated that hallmark genes related to fatty acid metabolism were highly expressed in samples with higher acylcarnitine content. These data suggest that cells in the core and the edge of the tumor undergo different fatty acid metabolism, resulting in different chemical environments within the tumor. This may influence drug distribution through changes in tissue drug affinity or transport and constitute an important consideration for therapeutic strategies in the treatment of GBM.
Significance:
GBM tumors exhibit a metabolic gradient that should be taken into consideration when designing therapeutic strategies for treatment.

See related commentary by Tan and Weljie, p. 1231
Data from Activation of β-Catenin Cooperates with Loss of Pten to Drive AR-Independent Castration-Resistant Prostate Cancer
Authors: Patel Rachana , Brzezinska Elspeth A. , Repiscak Peter , Ahmad Imran , Mui Ernest , Gao Meiling , Blomme Arnaud , Harle Victoria , Tan Ee Hong , Malviya Gaurav , Mrowinska Agata , Loveridge Carolyn J. , Rushworth Linda K. , Edwards Joanne , Ntala Chara , Nixon Colin , Hedley Ann , Mackay Gillian , Tardito Saverio , Sansom Owen J. , Leung Hing Y.
Published: March 2024

Abstract
Inhibition of the androgen receptor (AR) is the main strategy to treat advanced prostate cancers. AR-independent treatment-resistant prostate cancer is a major unresolved clinical problem. Patients with prostate cancer with alterations in canonical WNT pathway genes, which lead to β-catenin activation, are refractory to AR-targeted therapies. Here, using clinically relevant murine prostate cancer models, we investigated the significance of β-catenin activation in prostate cancer progression and treatment resistance. β-Catenin activation, independent of the cell of origin, cooperated with Pten loss to drive AR-independent castration-resistant prostate cancer. Prostate tumors with β-catenin activation relied on the noncanonical WNT ligand WNT5a for sustained growth. WNT5a repressed AR expression and maintained the expression of c-Myc, an oncogenic effector of β-catenin activation, by mediating nuclear localization of NFκBp65 and β-catenin. Overall, WNT/β-catenin and AR signaling are reciprocally inhibited. Therefore, inhibiting WNT/β-catenin signaling by limiting WNT secretion in concert with AR inhibition may be useful for treating prostate cancers with alterations in WNT pathway genes.
Significance:
Targeting of both AR and WNT/β-catenin signaling may be required to treat prostate cancers that exhibit alterations of the WNT pathway.
Data from ETV4 Is Necessary for Estrogen Signaling and Growth in Endometrial Cancer Cells
Authors: Rodriguez Adriana C. , Vahrenkamp Jeffery M. , Berrett Kristofer C. , Clark Kathleen A. , Guillen Katrin P. , Scherer Sandra D. , Yang Chieh-Hsiang , Welm Bryan E. , Janát-Amsbury Margit M. , Graves Barbara J. , Gertz Jason
Published: March 2024

Abstract
Estrogen signaling through estrogen receptor alpha (ER) plays a major role in endometrial cancer risk and progression, however, the molecular mechanisms underlying ER's regulatory role in endometrial cancer are poorly understood. In breast cancer cells, ER genomic binding is enabled by FOXA1 and GATA3, but the transcription factors that control ER genomic binding in endometrial cancer cells remain unknown. We previously identified ETV4 as a candidate factor controlling ER genomic binding in endometrial cancer cells, and here we explore the functional importance of ETV4. Homozygous deletion of ETV4, using CRISPR/Cas9, led to greatly reduced ER binding at the majority of loci normally bound by ER. Consistent with the dramatic loss of ER binding, the gene expression response to estradiol was dampened for most genes. ETV4 contributes to estrogen signaling in two distinct ways. ETV4 loss affects chromatin accessibility at some ER bound loci and impairs ER nuclear translocation. The diminished estrogen signaling upon ETV4 deletion led to decreased growth, particularly in 3D culture, where hollow organoids were formed and in vivo in the context of estrogen-dependent growth. These results show that ETV4 plays an important role in estrogen signaling in endometrial cancer cells.
Significance:
Estrogen receptor alpha (ER) is a key oncogene in endometrial cancer. This study uncovers ETV4 as an important factor in controlling the activity of ER and the growth of endometrial cancer cells.
Data from Postdiagnostic Fruit and Vegetable Consumption and Breast Cancer Survival: Prospective Analyses in the Nurses' Health Studies
Authors: Farvid Maryam S. , Holmes Michelle D. , Chen Wendy Y. , Rosner Bernard A. , Tamimi Rulla M. , Willett Walter C. , Eliassen A. Heather
Published: March 2024

Abstract
Fruits and vegetables contain many bioactive components that may contribute to improved survival after diagnosis of breast cancer, however, evidence to date is insufficient. We prospectively assessed the associations of postdiagnostic fruit and vegetable consumption with breast cancer–specific and all-cause mortality among 8,927 women with stage I–III breast cancer identified during follow-up of the Nurses' Health Study (NHS; 1980–2010) and NHSII (1991–2011), using a validated food frequency questionnaire completed every 4 years after diagnosis. We prospectively documented 2,521 deaths, including 1,070 from breast cancer through follow-up until 2014 in the NHS and 2015 in the NHSII. Total fruit and vegetable and total vegetable consumption was related to lower all-cause [HRQ5vsQ1, 0.82; 95% confidence interval (CI), 0.71–0.94; Ptrend = 0.004, and HRQ5vsQ1, 0.84; 95% CI, 0.72–0.97; Ptrend = 0.001, respectively], but not breast cancer–specific mortality. Total fruit consumption was not related to breast cancer–specific or all-cause mortality. Greater intake of green leafy and cruciferous vegetables was associated with lower all-cause mortality. Each 2 servings/week of blueberries was associated with a 25% (HR, 0.75; 95% CI, 0.60–0.94) lower breast cancer–specific and a 17% (HR, 0.83; 95% CI, 0.72–0.96) lower all-cause mortality. In contrast, higher fruit juice consumption was associated with higher breast cancer–specific (HRQ5vsQ1, 1.33; 95% CI, 1.09–1.63; Ptrend = 0.002) and all-cause mortality (HRQ5vsQ1, 1.19; 95% CI, 1.04–1.36; Ptrend = 0.003). Apple juice largely accounted for these higher risks and orange juice was not associated with risk. Higher postdiagnostic fruit and vegetable consumption among breast cancer survivors was not associated with breast cancer–specific mortality. However, our findings suggest that higher vegetable consumption, particularly green leafy and cruciferous vegetables, was associated with better overall survival among patients with breast cancer. Higher fruit juice consumption, but not orange juice, was associated with poorer breast cancer–specific and all-cause survival.
Significance:
A large-scale study shows that high fruit and vegetable consumption may be associated with better overall survival among breast cancer patients, while high fruit juice consumption may be associated with poorer porgnosis.
Data from ERK-Mediated Loss of miR-199a-3p and Induction of EGR1 Act as a “Toggle Switch” of GBM Cell Dedifferentiation into NANOG- and OCT4-Positive Cells
Authors: Almairac Fabien , Turchi Laurent , Sakakini Nathalie , Debruyne David Nicolas , Elkeurti Sarah , Gjernes Elisabet , Polo Beatrice , Bianchini Laurence , Fontaine Denys , Paquis Philippe , Chneiweiss Herve , Junier Marie-Pierre , Verrando Patrick , Burel-Vandenbos Fanny , Virolle Thierry
Published: March 2024

Abstract
There is great interest in understanding how the cancer stem cell population may be maintained in solid tumors. Here, we show that tumor cells exhibiting stem-like properties and expression of pluripotency markers NANOG and OCT4 can arise from original differentiated tumor cells freshly isolated from human glioblastomas (GBM) and that have never known any serum culture conditions. Induction of EGR1 by EGFR/ERK signaling promoted cell conversion from a less aggressive, more differentiated cellular state to a self-renewing and strongly tumorigenic state, expressing NANOG and OCT4. Expression of these pluripotency markers occurred before the cells re-entered the cell cycle, demonstrating their capacity to change and dedifferentiate without any cell divisions. In differentiated GBM cells, ERK-mediated repression of miR-199a-3p induced EGR1 protein expression and triggered dedifferentiation. Overall, this signaling pathway constitutes an ERK-mediated "toggle switch" that promotes pluripotency marker expression and stem-like features in GBM cells.
Significance:
This study defines an ERK-mediated molecular mechanism of dedifferentiation of GBM cells into a stem-like state, expressing markers of pluripotency.

See related commentary by Koncar and Agnihotri, p. 3195
Data from Towards Multidrug Adaptive Therapy
Authors: West Jeffrey , You Li , Zhang Jingsong , Gatenby Robert A. , Brown Joel S. , Newton Paul K. , Anderson Alexander R.A.
Published: March 2024

Abstract
A new ecologically inspired paradigm in cancer treatment known as “adaptive therapy” capitalizes on competitive interactions between drug-sensitive and drug-resistant subclones. The goal of adaptive therapy is to maintain a controllable stable tumor burden by allowing a significant population of treatment-sensitive cells to survive. These, in turn, suppress proliferation of the less-fit resistant populations. However, there remain several open challenges in designing adaptive therapies, particularly in extending these therapeutic concepts to multiple treatments. We present a cancer treatment case study (metastatic castrate-resistant prostate cancer) as a point of departure to illustrate three novel concepts to aid the design of multidrug adaptive therapies. First, frequency-dependent “cycles” of tumor evolution can trap tumor evolution in a periodic, controllable loop. Second, the availability and selection of treatments may limit the evolutionary “absorbing region” reachable by the tumor. Third, the velocity of evolution significantly influences the optimal timing of drug sequences. These three conceptual advances provide a path forward for multidrug adaptive therapy.
Significance:
Driving tumor evolution into periodic, repeatable treatment cycles provides a path forward for multidrug adaptive therapy.
Data from A Very Long-Acting PARP Inhibitor Suppresses Cancer Cell Growth in DNA Repair-Deficient Tumor Models
Authors: Fontaine Shaun D. , Ashley Gary W. , Houghton Peter J. , Kurmasheva Raushan T. , Diolaiti Morgan , Ashworth Alan , Peer Cody J. , Nguyen Ryan , Figg William D. , Beckford-Vera Denis R. , Santi Daniel V.
Published: March 2024

Abstract
PARP inhibitors are approved for treatment of cancers with BRCA1 or BRCA2 defects. In this study, we prepared and characterized a very long-acting PARP inhibitor. Synthesis of a macromolecular prodrug of talazoparib (TLZ) was achieved by covalent conjugation to a PEG40kDa carrier via a β-eliminative releasable linker. A single injection of the PEG∼TLZ conjugate was as effective as ∼30 daily oral doses of TLZ in growth suppression of homologous recombination-defective tumors in mouse xenografts. These included the KT-10 Wilms' tumor with a PALB2 mutation, the BRCA1-deficient MX-1 triple-negative breast cancer, and the BRCA2-deficient DLD-1 colon cancer; the prodrug did not inhibit an isogenic DLD-1 tumor with wild-type BRCA2. Although the half-life of PEG∼TLZ and released TLZ in the mouse was only ∼1 day, the exposure of released TLZ from a single safe, effective dose of the prodrug exceeded that of oral TLZ given daily over one month. μPET/CT imaging showed high uptake and prolonged retention of an 89Zr-labeled surrogate of PEG∼TLZ in the MX-1 BRCA1-deficient tumor. These data suggest that the long-lasting antitumor effect of the prodrug is due to a combination of its long t1/2, the high exposure of TLZ released from the prodrug, increased tumor sensitivity upon continued exposure, and tumor accumulation. Using pharmacokinetic parameters of TLZ in humans, we designed a long-acting PEG∼TLZ for humans that may be superior in efficacy to daily oral TLZ and would be useful for treatment of PARP inhibitor-sensitive cancers in which oral medications are not tolerated.
Significance:
These findings demonstrate that a single injection of a long-acting prodrug of the PARP inhibitor talazoparib in murine xenografts provides tumor suppression equivalent to a month of daily dosing of talazoparib.
Data from Genomic and Epigenomic Landscaping Defines New Therapeutic Targets for Adenosquamous Carcinoma of the Pancreas
Authors: Lenkiewicz Elizabeth , Malasi Smriti , Hogenson Tara L. , Flores Luis F. , Barham Whitney , Phillips William J. , Roesler Alexander S. , Chambers Kendall R. , Rajbhandari Nirakar , Hayashi Akimasa , Antal Corina E. , Downes Michael , Grandgenett Paul M. , Hollingsworth Michael A. , Cridebring Derek , Xiong Yuning , Lee Jeong-Heon , Ye Zhenqing , Yan Huihuang , Hernandez Matthew C. , Leiting Jennifer L. , Evans Ronald M. , Ordog Tamas , Truty Mark J. , Borad Mitesh J. , Reya Tannishtha , Von Hoff Daniel D. , Fernandez-Zapico Martin E. , Barrett Michael T.
Published: March 2024

Abstract
Adenosquamous cancer of the pancreas (ASCP) is a subtype of pancreatic cancer that has a worse prognosis and greater metastatic potential than the more common pancreatic ductal adenocarcinoma (PDAC) subtype. To distinguish the genomic landscape of ASCP and identify actionable targets for this lethal cancer, we applied DNA content flow cytometry to a series of 15 tumor samples including five patient-derived xenografts (PDX). We interrogated purified sorted tumor fractions from these samples with whole-genome copy-number variant (CNV), whole-exome sequencing, and Assay for Transposase-Accessible Chromatin using sequencing (ATAC-seq) analyses. These identified a variety of somatic genomic lesions targeting chromatin regulators in ASCP genomes that were superimposed on well-characterized genomic lesions including mutations in TP53 (87%) and KRAS (73%), amplification of MYC (47%), and homozygous deletion of CDKN2A (40%) that are common in PDACs. Furthermore, a comparison of ATAC-seq profiles of three ASCP and three PDAC genomes using flow-sorted PDX models identified genes with accessible chromatin unique to the ASCP genomes, including the lysine methyltransferase SMYD2 and the pancreatic cancer stem cell regulator RORC in all three ASCPs, and a FGFR1-ERLIN2 fusion associated with focal CNVs in both genes in a single ASCP. Finally, we demonstrate significant activity of a pan FGFR inhibitor against organoids derived from the FGFR1-ERLIN2 fusion–positive ASCP PDX model. Our results suggest that the genomic and epigenomic landscape of ASCP provide new strategies for targeting this aggressive subtype of pancreatic cancer.
Significance:
These data provide a unique description of the ASCP genomic and epigenomic landscape and identify candidate therapeutic targets for this dismal cancer.
Data from Dynamic Regulation of Expression of KRAS and Its Effectors Determines the Ability to Initiate Tumorigenesis in Pancreatic Acinar Cells
Authors: Assi Mohamad , Achouri Younes , Loriot Axelle , Dauguet Nicolas , Dahou Hajar , Baldan Jonathan , Libert Maxime , Fain Jean S. , Guerra Carmen , Bouwens Luc , Barbacid Mariano , Lemaigre Frédéric P. , Jacquemin Patrick
Published: March 2024

Abstract
Pancreatic acinar cells are a cell type of origin for pancreatic cancer that become progressively less sensitive to tumorigenesis induced by oncogenic Kras mutations after birth. This sensitivity is increased when Kras mutations are combined with pancreatitis. Molecular mechanisms underlying these observations are still largely unknown. To identify these mechanisms, we generated the first CRISPR-edited mouse models that enable detection of wild-type and mutant KRAS proteins in vivo. Analysis of these mouse models revealed that more than 75% of adult acinar cells are devoid of detectable KRAS protein. In the 25% of acinar cells expressing KRAS protein, transcriptomic analysis highlighted a slight upregulation of the RAS and MAPK pathways. However, at the protein level, only marginal pancreatic expression of essential KRAS effectors, including C-RAF, was observed. The expression of KRAS and its effectors gradually decreased after birth. The low sensitivity of adult acinar cells to Kras mutations resulted from low expression of KRAS and its effectors and the subsequent lack of activation of RAS/MAPK pathways. Pancreatitis triggered expression of KRAS and its effectors as well as subsequent activation of downstream signaling; this induction required the activity of EGFR. Finally, expression of C-RAF in adult pancreas was required for pancreatic tumorigenesis. In conclusion, our study reveals that control of the expression of KRAS and its effectors regulates the sensitivity of acinar cells to transformation by oncogenic Kras mutations.
Significance:
This study generates new mouse models to study regulation of KRAS during pancreatic tumorigenesis and highlights a novel mechanism through which pancreatitis sensitizes acinar cells to Kras mutations.
Data from Breast Cancer Cell Detection and Characterization from Breast Milk–Derived Cells
Authors: Bhat-Nakshatri Poornima , Kumar Brijesh , Simpson Ed , Ludwig Kandice K. , Cox Mary L. , Gao Hongyu , Liu Yunlong , Nakshatri Harikrishna
Published: March 2024

Abstract
Radiologic techniques remain the main method for early detection for breast cancer and are critical to achieve a favorable outcome from cancer. However, more sensitive detection methods to complement radiologic techniques are needed to enhance early detection and treatment strategies. Using our recently established culturing method that allows propagation of normal and cancerous breast epithelial cells of luminal origin, flow cytometry characterization, and genomic sequencing, we show that cancer cells can be detected in breast milk. Cells derived from milk from the breast with cancer were enriched for CD49f+/EpCAM−, CD44+/CD24−, and CD271+ cancer stem–like cells (CSC). These CSCs carried mutations within the cytoplasmic retention domain of HDAC6, stop/gain insertion in MORF4L1, and deletion mutations within SWI/SNF complex component SMARCC2. CSCs were sensitive to HDAC6 inhibitors, BET bromodomain inhibitors, and EZH2 inhibitors, as mutations in SWI/SNF complex components are known to increase sensitivity to these drugs. Among cells derived from breast milk of additional ten women not known to have breast cancer, two of them contained cells that were enriched for the CSC phenotype and carried mutations in NF1 or KMT2D, which are frequently mutated in breast cancer. Breast milk–derived cells with NF1 mutations also carried copy-number variations in CDKN2C, PTEN, and REL genes. The approach described here may enable rapid cancer cell characterization including driver mutation detection and therapeutic screening for pregnancy/postpartum breast cancers. Furthermore, this method can be developed as a surveillance or early detection tool for women at high risk for developing breast cancer.
Significance:
These findings describe how a simple method for characterization of cancer cells in pregnancy and postpartum breast cancer can be exploited as a surveillance tool for women at risk of developing breast cancer.
Data from SCIRT lncRNA Restrains Tumorigenesis by Opposing Transcriptional Programs of Tumor-Initiating Cells
Authors: Zagorac Sladjana , de Giorgio Alex , Dabrowska Aleksandra , Kalisz Mark , Casas-Vila Nuria , Cathcart Paul , Yiu Angela , Ottaviani Silvia , Degani Neta , Lombardo Ylenia , Tweedie Alistair , Nissan Tracy , Vance Keith W. , Ulitsky Igor , Stebbing Justin , Castellano Leandro
Published: March 2024

Abstract
In many tumors, cells transition reversibly between slow-proliferating tumor-initiating cells (TIC) and their differentiated, faster-growing progeny. Yet, how transcriptional regulation of cell-cycle and self-renewal genes is orchestrated during these conversions remains unclear. In this study, we show that as breast TIC form, a decrease in cell-cycle gene expression and increase in self-renewal gene expression are coregulated by SOX2 and EZH2, which colocalize at CpG islands. This pattern was negatively controlled by a novel long noncoding RNA (lncRNA) that we named Stem Cell Inhibitory RNA Transcript (SCIRT), which was markedly upregulated in tumorspheres but colocalized with and counteracted EZH2 and SOX2 during cell-cycle and self-renewal regulation to restrain tumorigenesis. SCIRT specifically interacted with EZH2 to increase EZH2 affinity to FOXM1 without binding the latter. In this manner, SCIRT induced transcription at cell-cycle gene promoters by recruiting FOXM1 through EZH2 to antagonize EZH2-mediated effects at target genes. Conversely, on stemness genes, FOXM1 was absent and SCIRT antagonized EZH2 and SOX2 activity, balancing toward repression. These data suggest that the interaction of an lncRNA with EZH2 can alter the affinity of EZH2 for its protein-binding partners to regulate cancer cell state transitions.
Significance:
These findings show that a novel lncRNA SCIRT counteracts breast tumorigenesis by opposing transcriptional networks associated with cell cycle and self-renewal.

See related commentary by Pardini and Dragomir, p. 535
Data from The Microbiome and Cancer: Creating Friendly Neighborhoods and Removing the Foes Within
Authors: Parida Sheetal , Sharma Dipali
Published: March 2024

Abstract
The human body is colonized by the microbial cells that are estimated to be as abundant as human cells, yet their genome is roughly 100 times the human genome, providing significantly more genetic diversity. The past decade has observed an explosion of interest in examining the existence of microbiota in the human body and understanding its role in various diseases including inflammatory bowel disease, neurologic diseases, cardiovascular disorders, and cancer. Many studies have demonstrated differential community composition between normal tissue and cancerous tissue, paving the way for investigations focused on deciphering the cause-and-effect relationships between specific microbes and initiation and progression of various cancers. Also, evolving are the strategies to alter tumor-associated dysbiosis and move it toward eubiosis with holistic approaches to change the entire neighborhood or to neutralize pathogenic strains. In this review, we discuss important pathogenic bacteria and the underlying mechanisms by which they affect cancer progression. We summarize key microbiota alterations observed in multiple tumor niches, their association with clinical stages, and their potential use in cancer diagnosis and management. Finally, we discuss microbiota-based therapeutic approaches.
Data from Unraveling the Mysteries of PAX8 in Reproductive Tract Cancers
Authors: Chaves-Moreira Daniele , Morin Patrice J. , Drapkin Ronny
Published: March 2024

Abstract
Paired Box 8 (PAX8) is a lineage-specific transcription factor that has essential roles during embryogenesis and tumorigenesis. The importance of PAX8 in the development of the reproductive system is highlighted by abnormalities observed upon the loss or mutation of this PAX family member. In cancer, PAX8 expression is deregulated in a key set of neoplasms, including those arising from the Müllerian ducts. The roles of PAX8 in oncogenesis are diverse and include epigenetic remodeling, stimulation of proliferation, inhibition of apoptosis, and regulation of angiogenesis. PAX8 can interact with different protein partners during cancer progression and may exhibit significant function-altering alternative splicing. Moreover, expression of PAX8 in cancer can also serve as a biomarker for diagnostic and prognostic purposes. In this review, we focus on the roles of PAX8 in cancers of the reproductive system. Understanding the diverse mechanisms of action of PAX8 in development and oncogenesis may identify new vulnerabilities in malignancies that currently lack effective therapies.
Data from Axl and Mertk Receptors Cooperate to Promote Breast Cancer Progression by Combined Oncogenic Signaling and Evasion of Host Antitumor Immunity
Authors: Davra Viralkumar , Kumar Sushil , Geng Ke , Calianese David , Mehta Dhriti , Gadiyar Varsha , Kasikara Canan , Lahey Kevin C. , Chang Yun-juan , Wichroski Michael , Gao Chan , De Lorenzo Mariana S. , Kotenko Sergei V. , Bergsbaken Tessa , Mishra Pankaj K. , Gause William C. , Quigley Michael , Spires Thomas E. , Birge Raymond B.
Published: March 2024

Abstract
Despite the promising clinical benefit of targeted and immune checkpoint blocking therapeutics, current strategies have limited success in breast cancer, indicating that additional inhibitory pathways are required to complement existing therapeutics. TAM receptors (Tyro-3, Axl, and Mertk) are often correlated with poor prognosis because of their capacities to sustain an immunosuppressive environment. Here, we ablate Axl on tumor cells using CRISPR/Cas9 gene editing, and by targeting Mertk in the tumor microenvironment (TME), we observed distinct functions of TAM as oncogenic kinases, as well as inhibitory immune receptors. Depletion of Axl suppressed cell intrinsic oncogenic properties, decreased tumor growth, reduced the incidence of lung metastasis and increased overall survival of mice when injected into mammary fat pad of syngeneic mice, and demonstrated synergy when combined with anti-PD-1 therapy. Blockade of Mertk function on macrophages decreased efferocytosis, altered the cytokine milieu, and resulted in suppressed macrophage gene expression patterns. Mertk-knockout mice or treatment with anti-Mertk–neutralizing mAb also altered the cellular immune profile, resulting in a more inflamed tumor environment with enhanced T-cell infiltration into tumors and T-cell–mediated cytotoxicity. The antitumor activity from Mertk inhibition was abrogated by depletion of cytotoxic CD8α T cells by using anti-CD8α mAb or by transplantation of tumor cells into B6.CB17-Prkdc SCID mice. Our data indicate that targeting Axl expressed on tumor cells and Mertk in the TME is predicted to have a combinatorial benefit to enhance current immunotherapies and that Axl and Mertk have distinct functional activities that impair host antitumor response.
Significance:
This study demonstrates how TAM receptors act both as oncogenic tyrosine kinases and as receptors that mediate immune evasion in cancer progression.
Data from PKCϵ Is Required for KRAS-Driven Lung Tumorigenesis
Authors: Garg Rachana , Cooke Mariana , Benavides Fernando , Abba Martín C. , Cicchini Michelle , Feldser David M. , Kazanietz Marcelo G.
Published: March 2024

Abstract
Non–small cell lung cancer (NSCLC) is the most frequent subtype of lung cancer and remains a highly lethal malignancy and one of the leading causes of cancer-related deaths worldwide. Mutant KRAS is the prevailing oncogenic driver of lung adenocarcinoma, the most common histologic form of NSCLC. In this study, we examined the role of PKCε, an oncogenic kinase highly expressed in NSCLC and other cancers, in KRAS-driven tumorigenesis. Database analysis revealed an association between PKCε expression and poor outcome in patients with lung adenocarcinoma specifically harboring KRAS mutations. A PKCε-deficient, conditionally activatable allele of oncogenic Kras (LSL-KrasG12D;PKCε−/− mice) demonstrated the requirement of PKCε for Kras-driven lung tumorigenesis in vivo, which was consistent with impaired transformed growth reported in PKCε-deficient KRAS-dependent NSCLC cells. Moreover, PKCε-knockout mice were found to be less susceptible to lung tumorigenesis induced by benzo[a]pyrene, a carcinogen that induces mutations in Kras. Mechanistic analysis using RNA sequencing revealed little overlap for PKCε and KRAS in the control of genes and biological pathways relevant in NSCLC, suggesting that a permissive role of PKCε in KRAS-driven lung tumorigenesis may involve nonredundant mechanisms. Our results thus, highlight the relevance and potential of targeting PKCε for lung cancer therapeutics.
Significance:
These findings demonstrate that KRAS-mediated tumorigenesis requires PKCε expression and highlight the potential for developing PKCε-targeted therapies for oncogenic RAS-driven malignancies.
Data from Enhanced Antitumor Immunity via Endocrine Therapy Prevents Mammary Tumor Relapse and Increases Immune Checkpoint Blockade Sensitivity
Authors: Sequeira Gonzalo R. , Sahores Ana , Dalotto-Moreno Tomás , Perrotta Ramiro M. , Pataccini Gabriela , Vanzulli Silvia I. , Polo María L. , Radisky Derek C. , Sartorius Carol A. , Novaro Virginia , Lamb Caroline A. , Rabinovich Gabriel A. , Salatino Mariana , Lanari Claudia
Published: March 2024

Abstract
The role of active antitumor immunity in hormone receptor–positive (HR+) breast cancer has been historically underlooked. The aim of this study was to determine the contribution of the immune system to antiprogestin-induced tumor growth inhibition using a hormone-dependent breast cancer model. BALB/c-GFP+ bone marrow (BM) cells were transplanted into immunodeficient NSG mice to generate an immunocompetent NSG/BM-GFP+ (NSG-R) mouse model. Treatment with the antiprogestin mifepristone (MFP) inhibited growth of 59–2-HI tumors with similar kinetics in both animal models. Interestingly, MFP treatment reshaped the tumor microenvironment, enhancing the production of proinflammatory cytokines and chemokines. Tumors in MFP-treated immunocompetent mice showed increased infiltration of F4/80+ macrophages, natural killer, and CD8 T cells, displaying a central memory phenotype. Mechanistically, MFP induced immunogenic cell death (ICD) in vivo and in vitro, as depicted by the expression and subcellular localization of the alarmins calreticulin and HMGB-1 and the induction of an ICD gene program. Moreover, MFP-treated tumor cells efficiently activated immature dendritic cells, evidenced by enhanced expression of MHC-II and CD86, and induced a memory T-cell response, attenuating tumor onset and growth after re-challenge. Finally, MFP treatment increased the sensitivity of HR+ 59–2-HI tumor to PD-L1 blockade, suggesting that antiprogestins may improve immunotherapy response rates. These results contribute to a better understanding of the mechanisms underlying the antitumor effect of hormonal treatment and the rational design of therapeutic combinations based on endocrine and immunomodulatory agents in HR+ breast cancer.
Significance:
Antiprogestin therapy induces immunogenic tumor cell death in PRA-overexpressing tumors, eliciting an adaptive immune memory response that protects mice from future tumor recurrence and increases sensitivity to PD-L1 blockade.
Data from KRAS Controls Pancreatic Cancer Cell Lipid Metabolism and Invasive Potential through the Lipase HSL
Authors: Rozeveld Cody N. , Johnson Katherine M. , Zhang Lizhi , Razidlo Gina L.
Published: March 2024

Abstract
Oncogene-induced metabolic reprogramming is a hallmark of pancreatic cancer (PDAC), yet the metabolic drivers of metastasis are unclear. In PDAC, obesity and excess fatty acids accelerate tumor growth and increase metastasis. Here, we report that excess lipids, stored in organelles called lipid droplets (LD), are a key resource to fuel the energy-intensive process of metastasis. The oncogene KRAS controlled the storage and utilization of LD through regulation of hormone-sensitive lipase (HSL), which was downregulated in human PDAC. Disruption of the KRAS–HSL axis reduced lipid storage, reprogrammed tumor cell metabolism, and inhibited invasive migration in vitro and metastasis in vivo. Finally, microscopy-based metabolic analysis revealed that migratory cells selectively utilize oxidative metabolism during the process of migration to metabolize stored lipids and fuel invasive migration. Taken together, these results reveal a mechanism that can be targeted to attenuate PDAC metastasis.
Significance:
KRAS-dependent regulation of HSL biases cells towards lipid storage for subsequent utilization during invasion of pancreatic cancer cells, representing a potential target for therapeutic intervention.

See related commentary by Man et al., p. 4886
Data from Activation of Receptor Tyrosine Kinases Mediates Acquired Resistance to MEK Inhibition in Malignant Peripheral Nerve Sheath Tumors
Authors: Wang Jiawan , Pollard Kai , Calizo Ana , Pratilas Christine A.
Published: March 2024

Abstract
Malignant peripheral nerve sheath tumors often arise in patients with neurofibromatosis type 1 and are among the most treatment-refractory types of sarcoma. Overall survival in patients with relapsed disease remains poor, and thus novel therapeutic approaches are needed. NF1 is essential for negative regulation of RAS activity and is altered in about 90% of malignant peripheral nerve sheath tumors (MPNST). A complex interplay of upstream signaling and parallel RAS-driven pathways characterizes NF1-driven tumorigenesis, and inhibiting more than one RAS effector pathway is therefore necessary. To devise potential combination therapeutic strategies, we identified actionable alterations in signaling that underlie adaptive and acquired resistance to MEK inhibitor (MEKi). Using a series of proteomic, biochemical, and genetic approaches in an in vitro model of MEKi resistance provided a rationale for combination therapies. HGF/MET signaling was elevated in the MEKi-resistant model. HGF overexpression conferred resistance to MEKi in parental cells. Depletion of HGF or MET restored sensitivity of MEKi-resistant cells to MEKi. Finally, a combination of MEK and MET inhibition demonstrated activity in models of MPNST and may therefore be effective in patients with MPNST harboring genetic alterations in NF1.
Significance:
This study demonstrates that MEKi plus MET inhibitor may delay or prevent a novel mechanism of acquired MEKi resistance, with clinical implications for MPNST patients harboring NF1 alterations.
Data from MEK Inhibition Reverses Aberrant Signaling in Melanoma Cells through Reorganization of NRas and BRAF in Self Nanoclusters
Authors: Yakovian Oren , Sajman Julia , Arafeh Rand , Neve-Oz Yair , Alon Michal , Samuels Yardena , Sherman Eilon
Published: March 2024

Abstract
Hotspot mutations of the oncogenes BRAF and NRas are the most common genetic alterations in cutaneous melanoma. Still, the nanoscale organization and signal coupling of these proteins remain incompletely understood, particularly upon expression of oncogenic NRas mutants. Here we employed single-molecule localization microscopy to study the nanoscale organization of NRas and BRAF at the plasma membrane (PM) of melanoma cells. NRas and BRAF resided in self-clusters that did not associate well in resting cells. In EGF-activated cells, NRas clusters became more diffused while overall protein levels at the PM increased; thus allowing enhanced association of NRas and BRAF and downstream signaling. In multiple melanoma cell lines, mutant NRas resided in more pronounced self-clusters relative to wild-type (WT) NRas yet associated more with the clustered and more abundant BRAF. In cells resistant to trametinib, a clinical MEK inhibitor (MEKi), a similar coclustering of NRas and BRAF was observed upon EGF activation. Strikingly, treatment of cells expressing mutant NRas with trametinib reversed the effect of mutant NRas expression by restoring the nonoverlapping self-clusters of NRas and BRAF and by reducing their PM levels and elevated pERK levels caused by mutant NRas. Our results indicate a new mechanism for signal regulation of NRas in melanoma through its nanoscale dynamic organization and a new mechanism for MEKi function in melanoma cells carrying NRas mutations but lacking MEK mutations.
Significance:
Nanoscale dynamic organization of WT and mutant NRas relative to BRAF serves as a regulatory mechanism for NRas signaling and may be a viable therapeutic target for its sensitivity to MEKi.
Data from ERK1/2 Signaling Induces Upregulation of ANGPT2 and CXCR4 to Mediate Liver Metastasis in Colon Cancer
Authors: Urosevic Jelena , Blasco María Teresa , Llorente Alicia , Bellmunt Anna , Berenguer-Llergo Antoni , Guiu Marc , Cañellas Adrià , Fernandez Esther , Burkov Ivan , Clapés Maria , Cartanà Mireia , Figueras-Puig Cristina , Batlle Eduard , Nebreda Angel R. , Gomis Roger R.
Published: March 2024

Abstract
Carcinoma development in colorectal cancer is driven by genetic alterations in numerous signaling pathways. Alterations in the RAS-ERK1/2 pathway are associated with the shortest overall survival for patients after diagnosis of colorectal cancer metastatic disease, yet how RAS–ERK signaling regulates colorectal cancer metastasis remains unknown. In this study, we used an unbiased screening approach based on selection of highly liver metastatic colorectal cancer cells in vivo to determine genes associated with metastasis. From this, an ERK1/2-controlled metastatic gene set (EMGS) was defined. EMGS was associated with increased recurrence and reduced survival in patients with colorectal cancer tumors. Higher levels of EMGS expression were detected in the colorectal cancer subsets consensus molecular subtype (CMS)1 and CMS4. ANGPT2 and CXCR4, two genes within the EMGS, were subjected to gain-of-function and loss-of-function studies in several colorectal cancer cell lines and then tested in clinical samples. The RAS–ERK1/2 axis controlled expression of the cytokine ANGPT2 and the cytokine receptor CXCR4 in colorectal cancer cells, which facilitated development of liver but not lung metastases, suggesting that ANGPT2 and CXCR4 are important for metastatic outgrowth in the liver. CXCR4 controlled the expression of cytokines IL10 and CXCL1, providing evidence for a causal role of IL10 in supporting liver colonization. In summary, these studies demonstrate that amplification of ERK1/2 signaling in KRAS-mutated colorectal cancer cells affects the cytokine milieu of the tumors, possibly affecting tumor–stroma interactions and favoring liver metastasis formation.
Significance:
These findings identify amplified ERK1/2 signaling in KRAS-mutated colorectal cancer cells as a driver of tumor–stroma interactions that favor formation of metastases in the liver.