Many cancers harbor oncogenic mutations of KRAS. Effectors mediating cancer progression, invasion, and metastasis in KRAS-mutated cancers are only incompletely understood. Here we identify cancer ...cell-expressed murine TRAIL-R, whose main function ascribed so far has been the induction of apoptosis as a crucial mediator of KRAS-driven cancer progression, invasion, and metastasis and in vivo Rac-1 activation. Cancer cell-restricted genetic ablation of murine TRAIL-R in autochthonous KRAS-driven models of non-small-cell lung cancer (NSCLC) and pancreatic ductal adenocarcinoma (PDAC) reduces tumor growth, blunts metastasis, and prolongs survival by inhibiting cancer cell-autonomous migration, proliferation, and invasion. Consistent with this, high TRAIL-R2 expression correlates with invasion of human PDAC into lymph vessels and with shortened metastasis-free survival of KRAS-mutated colorectal cancer patients.
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•mTRAIL-R promotes KRAS-driven lung and pancreatic cancer growth and metastasis•Human TRAIL-R2 promotes tumor growth, migration, invasion, and metastasis•Endogenous mTRAIL-R constitutively activates Rac1 in vivo in tumors•TRAIL-R2 expression positively correlates with the onset of metastasis in patients
von Karstedt et al. show that mouse TRAIL-R and human TRAIL-R2, but not TRAIL-R1, are important for the progression, invasion, and metastasis of KRAS-mutant tumors through the regulation of Rac-1.
Background
Pulmonary metastasectomy is an integral part of the interdisciplinary treatment of patients with pulmonary metastases (PMs) from colorectal carcinoma (CRC). Although alterations in the ...epidermal growth factor receptor (EGFR) pathway are common in CRC, there is still insufficient data regarding PM. We hypothesized that EGFR expression and Kirsten rat sarcoma viral oncogene homolog (
KRAS
)/
BRAF
mutations (Mts) might be associated with clinicopathological variables and the outcome in patients undergoing pulmonary metastasectomy.
Methods
In this single-center study, 44 patients undergoing pulmonary metastasectomy from primary CRC were included and prospectively followed up. Tissue specimens of resected PMs were assessed. Restriction fragment length analysis was used for
BRAF V600E
and
KRAS
codons 12 and 13 Mt analyses. EGFR expression was evaluated by immunohistochemistry. Patients were followed up in 3–6-month intervals.
Results
EGFR expression was evident in 49 % of the PMs, whereas Mts in
KRAS
and
BRAF
were detected in 48 and 0 %, respectively. Time to lung-specific recurrence after metastasectomy was significantly decreased in patients with
KRAS
mutated PMs in univariate (
p
= 0.013) and multivariate analysis (
p
= 0.035), whereas EGFR expression had no impact on recurrence free survival. Moreover, KRAS Mts were associated with the number of PMs (
p
= 0.037) and with the lung as first site of recurrence after metastasectomy (
p
= 0.047).
Discussion
This is the first evaluation of EGFR pathway alterations in the setting of pulmonary metastasectomy. Our data suggest that patients with
KRAS
Mts are at high risk for early pulmonary recurrence and have a more diffuse pattern of metastasis. These findings may have impact on the therapeutic management of CRC patients with pulmonary spreading.
Pulmonary metastases are common in patients with primary colorectal cancer (CRC). Heat-shock protein 27 (Hsp27) is upregulated in activated fibroblasts during wound healing and systemically elevated ...in various diseases. Cancer-associated fibroblasts (CAFs) are also thought to play a role as prognostic and predictive markers in various malignancies including CRC. Surprisingly, the expression of Hsp27 has never been assessed in CAFs. Therefore we aimed to investigate the expression level of Hsp27 in CAFs and its clinical implications in patients with CRC lung metastases.
FFPE tissue samples from 51 pulmonary metastases (PMs) and 33 paired primary tumors were evaluated for alpha-SMA, CD31, Hsp27 and vimentin expression by immunohistochemistry and correlated with clinicopathological variables. 25 liver metastases served as control group. Moreover, serum samples (n=10) before and after pulmonary metastasectomy were assessed for circulating phospho-Hsp27 and total Hsp27 by ELISA.
Stromal expression of Hsp27 was observed in all PM and showed strong correlation with alpha-SMA (P<0.001) and vimentin (P<0.001). Strong stromal Hsp27 was associated with higher microvessel density in primary CRC and PM. Moreover, high stromal Hsp27 and αSMA expression were associated with decreased recurrence-free survival after pulmonary metastasectomy (P=0.018 and P=0.008, respectively) and overall survival (P=0.031 and P=0.017, respectively). Serum levels of phospho- and total Hsp27 dropped after metastasectomy to levels comparable to healthy controls.
Herein we describe for the first time that Hsp27 is highly expressed in tumor stroma of CRC. Stromal α-SMA and Hsp27 expressions correlate with the clinical outcome after pulmonary metastasectomy. Moreover, serum Hsp27 might pose a future marker for metastatic disease in CRC.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
KRAS oncoprotein is commonly mutated in human cancer, but effective therapies specifically targeting KRAS‐driven tumors remain elusive. Here, we show that combined treatment with fibroblast growth ...factor receptor 1 (FGFR1) and polo‐like kinase 1 (PLK1) inhibitors evoke synergistic cytotoxicity in KRAS‐mutant tumor models in vitro and in vivo. Pharmacological and genetic suppression of FGFR1 and PLK1 synergizes to enhance anti‐proliferative effects and cell death in KRAS‐mutant lung and pancreatic but not colon nor KRAS wild‐type cancer cells. Mechanistically, co‐targeting FGFR1 and PLK1 upregulates reactive oxygen species (ROS), leading to oxidative stress‐activated c‐Jun N‐terminal kinase (JNK)/p38 pathway and E2F1‐induced apoptosis. We further delineate that autophagy protects from PLK1/FGFR1 inhibitor cytotoxicity and that antagonizing the compensation mechanism by clinically approved chloroquine fully realizes the therapeutic potential of PLK1 and FGFR1 targeting therapy, producing potent and durable responses in KRAS‐mutant patient‐derived xenografts and a genetically engineered mouse model of Kras‐induced lung adenocarcinoma. These results suggest a previously unappreciated role for FGFR1 and PLK1 in the surveillance of metabolic stress and demonstrate a synergistic drug combination for treating KRAS‐mutant cancer.
SYNOPSIS
Human cancers driven by oncogenic KRAS mutations are common and among the most difficult‐to‐treat tumors. This study reports a synergistic drug combination by targeting FGFR1 and PLK1 and identifies autophagy as a protective mechanism that limits the efficacy of FGFR1/PLK1 inhibitor therapy in KRAS‐mutant lung cancer, suggesting a novel strategy to treat the daunting disease.
FGFR‐ and PLK1‐targeted agents synergize in inhibiting KRAS‐mutant lung and pancreatic cancer cells.
FGFR/PLK1 inhibitor therapy targets a metabolic liability by abrogating ROS homeostasis in KRAS‐mutant cancer cells.
Autophagy protects against FGFR/PLK1 inhibitor‐induced cytotoxicity.
Combined inhibition of FGFR, PLK1, and autophagy shows potent anti‐tumor efficacy in mouse models of KRAS‐mutant lung cancer.
Human cancers driven by oncogenic KRAS mutations are common and among the most difficult‐to‐treat tumors. This study reports a synergistic drug combination by targeting FGFR1 and PLK1 and identifies autophagy as a protective mechanism that limits the efficacy of FGFR1/PLK1 inhibitor therapy in KRAS‐mutant lung cancer, suggesting a novel strategy to treat the daunting disease.
Oncogenic KRAS mutations are prevalent in human cancers, but effective treatment of KRAS-mutant malignancies remains a major challenge in the clinic. Increasing evidence suggests that aberrant ...metabolism plays a central role in KRAS-driven oncogenic transformation. The aim of this study is to identify selective metabolic dependency induced by mutant KRAS and to exploit it for the treatment of the disease.
We performed an integrated analysis of RNAi- and CRISPR-based functional genomic datasets (n = 5) to identify novel genes selectively required for KRAS-mutant cancer. We further screened a customized library of chemical inhibitors for candidates that are synthetic lethal with NOP56 depletion. Functional studies were carried out by genetic knockdown using siRNAs and shRNAs, knockout using CRISPR/Cas9, and/or pharmacological inhibition, followed by cell viability and apoptotic assays. Protein expression was determined by Western blot. Metabolic ROS was measured by flow cytometry-based quantification.
We demonstrated that nucleolar protein 5A (NOP56), a core component of small nucleolar ribonucleoprotein complexes (snoRNPs) with an essential role in ribosome biogenesis, confers a metabolic dependency by regulating ROS homeostasis in KRAS-mutant lung cancer cells and that NOP56 depletion causes synthetic lethal susceptibility to inhibition of mTOR. Mechanistically, cancer cells with reduced NOP56 are subjected to higher levels of ROS and rely on mTOR signaling to balance oxidative stress and survive. We also discovered that IRE1α-mediated unfolded protein response (UPR) regulates this process by activating mTOR through p38 MAPK. Consequently, co-targeting of NOP56 and mTOR profoundly enhances KRAS-mutant tumor cell death in vitro and in vivo.
Our findings reveal a previously unrecognized mechanism in which NOP56 and mTOR cooperate to play a homeostatic role in the response to oxidative stress and suggest a new rationale for the treatment of KRAS-mutant cancers.
•High concordance rate in variant calls from tumor biopsies and the corresponding liquid biopsy-derived DNA sample.•ctDNA sequencing allows for unbiased characterization of molecular tumor ...architecture and reveal the presence of otherwise undetectable resistance-mediating tumor cell clones.•Serial ctDNA analysis allows for monitoring tumor dynamics but limited by tumor cell clonal molecular heterogeneity.•cfDNA methylation analysis using methylation-sensitive restriction enzyme-coupled ddPCR can complement cfDNA mutation scoring to broaden the spectrum of eligible patients for molecular surveillance.
Radiology is the current standard for monitoring treatment responses in lung cancer. Limited sensitivity, exposure to ionizing radiations and related sequelae constitute some of its major limitation. Non-invasive and highly sensitive methods for early detection of treatment failures and resistance-associated disease progression would have additional clinical utility.
We analyzed serially collected plasma and paired tumor samples from lung cancer patients (61 with stage IV, 48 with stages I-III disease) and 61 healthy samples by means of next-generation sequencing, radiological imaging and droplet digital polymerase chain reaction (ddPCR) mutation and methylation assays.
A 62% variant concordance between tumor-reported and circulating-free DNA (cfDNA) sequencing was observed between baseline liquid and tissue biopsies in stage IV patients. Interestingly, ctDNA sequencing allowed for the identification of resistance-mediating p.T790M mutations in baseline plasma samples for which no such mutation was observed in the corresponding tissue. Serial circulating tumor DNA (ctDNA) mutation analysis by means of ddPCR revealed a general decrease in ctDNA loads between baseline and first reassessment. Additionally, serial ctDNA analyses only recapitulated computed tomography (CT) -monitored tumor dynamics of some, but not all lesions within the same patient. To complement ctDNA variant analysis we devised a ctDNA methylation assay (methcfDNA) based on methylation-sensitive restriction enzymes. cfDNA methylation showed and area under the curve (AUC) of > 0.90 in early and late stage cases. A decrease in methcfDNA between baseline and first reassessment was reflected by a decrease in CT-derive tumor surface area, irrespective of tumor mutational status.
Taken together, our data support the use of cfDNA sequencing for unbiased characterization of the molecular tumor architecture, highlights the impact of tumor architectural heterogeneity on ctDNA-based tumor surveillance and the added value of complementary approaches such as cfDNA methylation for early detection and monitoring
Early detection of cancer holds high promise for reducing cancer-related mortality. Detection of circulating tumor-specific nucleic acids holds promise, but sensitivity and specificity issues remain ...with current technology. We studied cell-free RNA (cfRNA) in patients with non-small cell lung cancer (NSCLC; n = 56 stage IV, n = 39 stages I-III), pancreatic cancer (PDAC, n = 20 stage III), malignant melanoma (MM, n = 12 stage III-IV), urothelial bladder cancer (UBC, n = 22 stage II and IV), and 65 healthy controls by means of next generation sequencing (NGS) and real-time droplet digital PCR (RT-ddPCR). We identified 192 overlapping upregulated transcripts in NSCLC and PDAC by NGS, more than 90% of which were noncoding. Previously reported transcripts (e.g., HOTAIRM1) were identified. Plasma cfRNA transcript levels of POU6F2-AS2 discriminated NSCLC from healthy donors (AUC = 0.82 and 0.76 for stages IV and I-III, respectively) and significantly associated (
= 0.017) with the established tumor marker Cyfra 21-1. cfRNA yield and POU6F2-AS transcript abundance discriminated PDAC patients from healthy donors (AUC = 1.0). POU6F2-AS2 transcript was significantly higher in MM (
= 0.044). In summary, our findings support further validation of cfRNA detection by RT-ddPCR as a biomarker for early detection of solid cancers.
Current therapy of KRAS-mutant lung cancer Ghimessy, Aron; Radeczky, Peter; Laszlo, Viktoria ...
Cancer and metastasis reviews,
12/2020, Letnik:
39, Številka:
4
Journal Article
Recenzirano
Odprti dostop
KRAS mutations are the most frequent gain-of-function alterations in patients with lung adenocarcinoma (LADC) in the Western world. Although they have been identified decades ago, prior efforts to ...target KRAS signaling with single-agent therapeutic approaches such as farnesyl transferase inhibitors, prenylation inhibition, impairment of KRAS downstream signaling, and synthetic lethality screens have been unsuccessful. Moreover, the role of KRAS oncogene in LADC is still not fully understood, and its prognostic and predictive impact with regards to the standard of care therapy remains controversial. Of note, KRAS-related studies that included general non-small cell lung cancer (NSCLC) population instead of LADC patients should be very carefully evaluated. Recently, however, comprehensive genomic profiling and wide-spectrum analysis of other co-occurring genetic alterations have identified unique therapeutic vulnerabilities. Novel targeted agents such as the covalent KRAS G12C inhibitors or the recently proposed combinatory approaches are some examples which may allow a tailored treatment for LADC patients harboring KRAS mutations. This review summarizes the current knowledge about the therapeutic approaches of KRAS-mutated LADC and provides an update on the most recent advances in KRAS-targeted anti-cancer strategies, with a focus on potential clinical implications.
Using the atomic force microscope to locally probe the cell membrane, we observed the formation of multiple tethers (thin nanotubes, each requiring a similar pulling force) as reproducible features ...within force profiles recorded on individual cells. Forces obtained with Chinese hamster ovary cells, a malignant human brain tumor cell line, and human endothelial cells (EA hy926) were found to be 28
±
10
pN, 29
±
9
pN, and 29
±
10
pN, respectively, independent of the nature of attachment to the cantilever. The rather large variation of the tether pulling forces measured at several locations on individual cells points to the existence of heterogeneity in the membrane properties of a morphologically homogeneous cell. Measurement of the summary lengths of the simultaneously extracted tethers provides a measure of the size of the available membrane reservoir through which co-existing tethers are associated. As expected, partial disruption of the actin cytoskeleton and removal of the hyaluronan backbone of the glycocalyx were observed to result in a marked decrease (30–50%) in the magnitude and a significant sharpening of the force distribution indicating reduced heterogeneity of membrane properties. Taken together, our results demonstrate the ability of the plasma membrane to locally produce multiple interdependent tethers—a process that could play an important role in the mechanical association of cells with their environment.
Malignant pleural mesothelioma (MPM) is a rare type of cancer with a grim prognosis. So far, no targetable oncogenic mutation was identified in MPM and biomarkers with predictive value toward drug ...sensitivity or resistance are also lacking. Nintedanib (BIBF1120) is a small-molecule tyrosine kinase inhibitor that showed promising efficacy preclinically and in phase II trial in MPM as an angiogenesis inhibitor combined with chemotherapy. However, the extended phase III trial failed. In this study, we investigated the effect of nintedanib on one of its targets, the SRC kinase, in two commercial and six novel MPM cell lines. Surprisingly, nintedanib treatment did not inhibit SRC activation in MPM cells and even increased phosphorylation of SRC in several cell lines. Combination treatment with the SRC inhibitor dasatinib could reverse this effect in all cell lines, however, the cellular response was dependent on the drug sensitivity of the cells. In 2 cell lines, with high sensitivity to both nintedanib and dasatinib, the drug combination had no synergistic effect but cell death was initiated. In 2 cell lines insensitive to nintedanib combination treatment reduced cell viability synergisticaly without cell death. In contrast, in these cells both treatments increased the autophagic flux assessed by degradation of the autophagy substrate p62 and increased presence of LC3B-II, increased number of GFP-LC3 puncta and decreased readings of the HiBiT-LC3 reporter. Additionaly, autophagy was synergistically promoted by the combined treatment. At the transcriptional level, analysis of lysosomal biogenesis regulator Transcription Factor EB (TFEB) showed that in all cell lines treated with nintedanib and to a lesser extent, with dasatinib, it became dephosphorylated and accumulated in the nucleus. Interestingly, the expression of certain known TFEB target genes implicated in autophagy or lysosomal biogenesis were significantly modified only in 1 cell line. Finally, we showed that autophagy induction in our MPM cell lines panel by nintedanib and dasatinib is independent of the AKT/mTOR and the ERK pathways. Our study reveals that autophagy can serve as a cytoprotective mechanism following nintedanib or dasatinib treatments in MPM cells.
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